diff: move diff.c to diff-lib.c to make room.

Now I am not doing any real "git-diff in C" yet, but this would
help before doing so.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/Makefile b/Makefile
index 8aed3af0165fe764d71184ffe0f35748d368e5a1..3ecd674c14d279e81a37c666cba419656fe044c0 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -199,7 +199,7 @@ LIB_H = \
        tree-walk.h log-tree.h
 
 DIFF_OBJS = \
-       diff.o diffcore-break.o diffcore-order.o \
+       diff-lib.o diffcore-break.o diffcore-order.o \
        diffcore-pickaxe.o diffcore-rename.o tree-diff.o combine-diff.o \
        diffcore-delta.o log-tree.o
 

diff --git a/diff-lib.c b/diff-lib.c
new file mode 100644 (file)
index 0000000..0a832c3
--- /dev/null
+++ b/diff-lib.c
@@ -0,0 +1,1736 @@
+/*
+ * Copyright (C) 2005 Junio C Hamano
+ */
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include "cache.h"
+#include "quote.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "xdiff-interface.h"
+
+static int use_size_cache;
+
+int diff_rename_limit_default = -1;
+
+int git_diff_config(const char *var, const char *value)
+{
+       if (!strcmp(var, "diff.renamelimit")) {
+               diff_rename_limit_default = git_config_int(var, value);
+               return 0;
+       }
+
+       return git_default_config(var, value);
+}
+
+static char *quote_one(const char *str)
+{
+       int needlen;
+       char *xp;
+
+       if (!str)
+               return NULL;
+       needlen = quote_c_style(str, NULL, NULL, 0);
+       if (!needlen)
+               return strdup(str);
+       xp = xmalloc(needlen + 1);
+       quote_c_style(str, xp, NULL, 0);
+       return xp;
+}
+
+static char *quote_two(const char *one, const char *two)
+{
+       int need_one = quote_c_style(one, NULL, NULL, 1);
+       int need_two = quote_c_style(two, NULL, NULL, 1);
+       char *xp;
+
+       if (need_one + need_two) {
+               if (!need_one) need_one = strlen(one);
+               if (!need_two) need_one = strlen(two);
+
+               xp = xmalloc(need_one + need_two + 3);
+               xp[0] = '"';
+               quote_c_style(one, xp + 1, NULL, 1);
+               quote_c_style(two, xp + need_one + 1, NULL, 1);
+               strcpy(xp + need_one + need_two + 1, "\"");
+               return xp;
+       }
+       need_one = strlen(one);
+       need_two = strlen(two);
+       xp = xmalloc(need_one + need_two + 1);
+       strcpy(xp, one);
+       strcpy(xp + need_one, two);
+       return xp;
+}
+
+static const char *external_diff(void)
+{
+       static const char *external_diff_cmd = NULL;
+       static int done_preparing = 0;
+
+       if (done_preparing)
+               return external_diff_cmd;
+       external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
+       done_preparing = 1;
+       return external_diff_cmd;
+}
+
+#define TEMPFILE_PATH_LEN              50
+
+static struct diff_tempfile {
+       const char *name; /* filename external diff should read from */
+       char hex[41];
+       char mode[10];
+       char tmp_path[TEMPFILE_PATH_LEN];
+} diff_temp[2];
+
+static int count_lines(const char *data, int size)
+{
+       int count, ch, completely_empty = 1, nl_just_seen = 0;
+       count = 0;
+       while (0 < size--) {
+               ch = *data++;
+               if (ch == '\n') {
+                       count++;
+                       nl_just_seen = 1;
+                       completely_empty = 0;
+               }
+               else {
+                       nl_just_seen = 0;
+                       completely_empty = 0;
+               }
+       }
+       if (completely_empty)
+               return 0;
+       if (!nl_just_seen)
+               count++; /* no trailing newline */
+       return count;
+}
+
+static void print_line_count(int count)
+{
+       switch (count) {
+       case 0:
+               printf("0,0");
+               break;
+       case 1:
+               printf("1");
+               break;
+       default:
+               printf("1,%d", count);
+               break;
+       }
+}
+
+static void copy_file(int prefix, const char *data, int size)
+{
+       int ch, nl_just_seen = 1;
+       while (0 < size--) {
+               ch = *data++;
+               if (nl_just_seen)
+                       putchar(prefix);
+               putchar(ch);
+               if (ch == '\n')
+                       nl_just_seen = 1;
+               else
+                       nl_just_seen = 0;
+       }
+       if (!nl_just_seen)
+               printf("\n\\ No newline at end of file\n");
+}
+
+static void emit_rewrite_diff(const char *name_a,
+                             const char *name_b,
+                             struct diff_filespec *one,
+                             struct diff_filespec *two)
+{
+       int lc_a, lc_b;
+       diff_populate_filespec(one, 0);
+       diff_populate_filespec(two, 0);
+       lc_a = count_lines(one->data, one->size);
+       lc_b = count_lines(two->data, two->size);
+       printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
+       print_line_count(lc_a);
+       printf(" +");
+       print_line_count(lc_b);
+       printf(" @@\n");
+       if (lc_a)
+               copy_file('-', one->data, one->size);
+       if (lc_b)
+               copy_file('+', two->data, two->size);
+}
+
+static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
+{
+       if (!DIFF_FILE_VALID(one)) {
+               mf->ptr = ""; /* does not matter */
+               mf->size = 0;
+               return 0;
+       }
+       else if (diff_populate_filespec(one, 0))
+               return -1;
+       mf->ptr = one->data;
+       mf->size = one->size;
+       return 0;
+}
+
+struct emit_callback {
+       const char **label_path;
+};
+
+static int fn_out(void *priv, mmbuffer_t *mb, int nbuf)
+{
+       int i;
+       struct emit_callback *ecbdata = priv;
+
+       if (ecbdata->label_path[0]) {
+               printf("--- %s\n", ecbdata->label_path[0]);
+               printf("+++ %s\n", ecbdata->label_path[1]);
+               ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
+       }
+       for (i = 0; i < nbuf; i++)
+               if (!fwrite(mb[i].ptr, mb[i].size, 1, stdout))
+                       return -1;
+       return 0;
+}
+
+struct diffstat_t {
+       struct xdiff_emit_state xm;
+
+       int nr;
+       int alloc;
+       struct diffstat_file {
+               char *name;
+               unsigned is_unmerged:1;
+               unsigned is_binary:1;
+               unsigned int added, deleted;
+       } **files;
+};
+
+static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
+               const char *name)
+{
+       struct diffstat_file *x;
+       x = xcalloc(sizeof (*x), 1);
+       if (diffstat->nr == diffstat->alloc) {
+               diffstat->alloc = alloc_nr(diffstat->alloc);
+               diffstat->files = xrealloc(diffstat->files,
+                               diffstat->alloc * sizeof(x));
+       }
+       diffstat->files[diffstat->nr++] = x;
+       x->name = strdup(name);
+       return x;
+}
+
+static void diffstat_consume(void *priv, char *line, unsigned long len)
+{
+       struct diffstat_t *diffstat = priv;
+       struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
+
+       if (line[0] == '+')
+               x->added++;
+       else if (line[0] == '-')
+               x->deleted++;
+}
+
+static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
+static const char minuses[]= "----------------------------------------------------------------------";
+
+static void show_stats(struct diffstat_t* data)
+{
+       char *prefix = "";
+       int i, len, add, del, total, adds = 0, dels = 0;
+       int max, max_change = 0, max_len = 0;
+       int total_files = data->nr;
+
+       if (data->nr == 0)
+               return;
+
+       for (i = 0; i < data->nr; i++) {
+               struct diffstat_file *file = data->files[i];
+
+               len = strlen(file->name);
+               if (max_len < len)
+                       max_len = len;
+
+               if (file->is_binary || file->is_unmerged)
+                       continue;
+               if (max_change < file->added + file->deleted)
+                       max_change = file->added + file->deleted;
+       }
+
+       for (i = 0; i < data->nr; i++) {
+               char *name = data->files[i]->name;
+               int added = data->files[i]->added;
+               int deleted = data->files[i]->deleted;
+
+               if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
+                       char *qname = xmalloc(len + 1);
+                       quote_c_style(name, qname, NULL, 0);
+                       free(name);
+                       data->files[i]->name = name = qname;
+               }
+
+               /*
+                * "scale" the filename
+                */
+               len = strlen(name);
+               max = max_len;
+               if (max > 50)
+                       max = 50;
+               if (len > max) {
+                       char *slash;
+                       prefix = "...";
+                       max -= 3;
+                       name += len - max;
+                       slash = strchr(name, '/');
+                       if (slash)
+                               name = slash;
+               }
+               len = max;
+
+               /*
+                * scale the add/delete
+                */
+               max = max_change;
+               if (max + len > 70)
+                       max = 70 - len;
+
+               if (data->files[i]->is_binary) {
+                       printf(" %s%-*s |  Bin\n", prefix, len, name);
+                       goto free_diffstat_file;
+               }
+               else if (data->files[i]->is_unmerged) {
+                       printf(" %s%-*s |  Unmerged\n", prefix, len, name);
+                       goto free_diffstat_file;
+               }
+               else if (added + deleted == 0) {
+                       total_files--;
+                       goto free_diffstat_file;
+               }
+
+               add = added;
+               del = deleted;
+               total = add + del;
+               adds += add;
+               dels += del;
+
+               if (max_change > 0) {
+                       total = (total * max + max_change / 2) / max_change;
+                       add = (add * max + max_change / 2) / max_change;
+                       del = total - add;
+               }
+               printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
+                               len, name, added + deleted,
+                               add, pluses, del, minuses);
+       free_diffstat_file:
+               free(data->files[i]->name);
+               free(data->files[i]);
+       }
+       free(data->files);
+       printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
+                       total_files, adds, dels);
+}
+
+#define FIRST_FEW_BYTES 8000
+static int mmfile_is_binary(mmfile_t *mf)
+{
+       long sz = mf->size;
+       if (FIRST_FEW_BYTES < sz)
+               sz = FIRST_FEW_BYTES;
+       if (memchr(mf->ptr, 0, sz))
+               return 1;
+       return 0;
+}
+
+static void builtin_diff(const char *name_a,
+                        const char *name_b,
+                        struct diff_filespec *one,
+                        struct diff_filespec *two,
+                        const char *xfrm_msg,
+                        int complete_rewrite)
+{
+       mmfile_t mf1, mf2;
+       const char *lbl[2];
+       char *a_one, *b_two;
+
+       a_one = quote_two("a/", name_a);
+       b_two = quote_two("b/", name_b);
+       lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
+       lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
+       printf("diff --git %s %s\n", a_one, b_two);
+       if (lbl[0][0] == '/') {
+               /* /dev/null */
+               printf("new file mode %06o\n", two->mode);
+               if (xfrm_msg && xfrm_msg[0])
+                       puts(xfrm_msg);
+       }
+       else if (lbl[1][0] == '/') {
+               printf("deleted file mode %06o\n", one->mode);
+               if (xfrm_msg && xfrm_msg[0])
+                       puts(xfrm_msg);
+       }
+       else {
+               if (one->mode != two->mode) {
+                       printf("old mode %06o\n", one->mode);
+                       printf("new mode %06o\n", two->mode);
+               }
+               if (xfrm_msg && xfrm_msg[0])
+                       puts(xfrm_msg);
+               /*
+                * we do not run diff between different kind
+                * of objects.
+                */
+               if ((one->mode ^ two->mode) & S_IFMT)
+                       goto free_ab_and_return;
+               if (complete_rewrite) {
+                       emit_rewrite_diff(name_a, name_b, one, two);
+                       goto free_ab_and_return;
+               }
+       }
+
+       if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
+               die("unable to read files to diff");
+
+       if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
+               printf("Binary files %s and %s differ\n", lbl[0], lbl[1]);
+       else {
+               /* Crazy xdl interfaces.. */
+               const char *diffopts = getenv("GIT_DIFF_OPTS");
+               xpparam_t xpp;
+               xdemitconf_t xecfg;
+               xdemitcb_t ecb;
+               struct emit_callback ecbdata;
+
+               ecbdata.label_path = lbl;
+               xpp.flags = XDF_NEED_MINIMAL;
+               xecfg.ctxlen = 3;
+               xecfg.flags = XDL_EMIT_FUNCNAMES;
+               if (!diffopts)
+                       ;
+               else if (!strncmp(diffopts, "--unified=", 10))
+                       xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
+               else if (!strncmp(diffopts, "-u", 2))
+                       xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
+               ecb.outf = fn_out;
+               ecb.priv = &ecbdata;
+               xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
+       }
+
+ free_ab_and_return:
+       free(a_one);
+       free(b_two);
+       return;
+}
+
+static void builtin_diffstat(const char *name_a, const char *name_b,
+               struct diff_filespec *one, struct diff_filespec *two,
+               struct diffstat_t *diffstat)
+{
+       mmfile_t mf1, mf2;
+       struct diffstat_file *data;
+
+       data = diffstat_add(diffstat, name_a ? name_a : name_b);
+
+       if (!one || !two) {
+               data->is_unmerged = 1;
+               return;
+       }
+
+       if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
+               die("unable to read files to diff");
+
+       if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
+               data->is_binary = 1;
+       else {
+               /* Crazy xdl interfaces.. */
+               xpparam_t xpp;
+               xdemitconf_t xecfg;
+               xdemitcb_t ecb;
+
+               xpp.flags = XDF_NEED_MINIMAL;
+               xecfg.ctxlen = 0;
+               xecfg.flags = 0;
+               ecb.outf = xdiff_outf;
+               ecb.priv = diffstat;
+               xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
+       }
+}
+
+struct diff_filespec *alloc_filespec(const char *path)
+{
+       int namelen = strlen(path);
+       struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
+
+       memset(spec, 0, sizeof(*spec));
+       spec->path = (char *)(spec + 1);
+       memcpy(spec->path, path, namelen+1);
+       return spec;
+}
+
+void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
+                  unsigned short mode)
+{
+       if (mode) {
+               spec->mode = canon_mode(mode);
+               memcpy(spec->sha1, sha1, 20);
+               spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
+       }
+}
+
+/*
+ * Given a name and sha1 pair, if the dircache tells us the file in
+ * the work tree has that object contents, return true, so that
+ * prepare_temp_file() does not have to inflate and extract.
+ */
+static int work_tree_matches(const char *name, const unsigned char *sha1)
+{
+       struct cache_entry *ce;
+       struct stat st;
+       int pos, len;
+
+       /* We do not read the cache ourselves here, because the
+        * benchmark with my previous version that always reads cache
+        * shows that it makes things worse for diff-tree comparing
+        * two linux-2.6 kernel trees in an already checked out work
+        * tree.  This is because most diff-tree comparisons deal with
+        * only a small number of files, while reading the cache is
+        * expensive for a large project, and its cost outweighs the
+        * savings we get by not inflating the object to a temporary
+        * file.  Practically, this code only helps when we are used
+        * by diff-cache --cached, which does read the cache before
+        * calling us.
+        */
+       if (!active_cache)
+               return 0;
+
+       len = strlen(name);
+       pos = cache_name_pos(name, len);
+       if (pos < 0)
+               return 0;
+       ce = active_cache[pos];
+       if ((lstat(name, &st) < 0) ||
+           !S_ISREG(st.st_mode) || /* careful! */
+           ce_match_stat(ce, &st, 0) ||
+           memcmp(sha1, ce->sha1, 20))
+               return 0;
+       /* we return 1 only when we can stat, it is a regular file,
+        * stat information matches, and sha1 recorded in the cache
+        * matches.  I.e. we know the file in the work tree really is
+        * the same as the <name, sha1> pair.
+        */
+       return 1;
+}
+
+static struct sha1_size_cache {
+       unsigned char sha1[20];
+       unsigned long size;
+} **sha1_size_cache;
+static int sha1_size_cache_nr, sha1_size_cache_alloc;
+
+static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
+                                                int find_only,
+                                                unsigned long size)
+{
+       int first, last;
+       struct sha1_size_cache *e;
+
+       first = 0;
+       last = sha1_size_cache_nr;
+       while (last > first) {
+               int cmp, next = (last + first) >> 1;
+               e = sha1_size_cache[next];
+               cmp = memcmp(e->sha1, sha1, 20);
+               if (!cmp)
+                       return e;
+               if (cmp < 0) {
+                       last = next;
+                       continue;
+               }
+               first = next+1;
+       }
+       /* not found */
+       if (find_only)
+               return NULL;
+       /* insert to make it at "first" */
+       if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
+               sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
+               sha1_size_cache = xrealloc(sha1_size_cache,
+                                          sha1_size_cache_alloc *
+                                          sizeof(*sha1_size_cache));
+       }
+       sha1_size_cache_nr++;
+       if (first < sha1_size_cache_nr)
+               memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
+                       (sha1_size_cache_nr - first - 1) *
+                       sizeof(*sha1_size_cache));
+       e = xmalloc(sizeof(struct sha1_size_cache));
+       sha1_size_cache[first] = e;
+       memcpy(e->sha1, sha1, 20);
+       e->size = size;
+       return e;
+}
+
+/*
+ * While doing rename detection and pickaxe operation, we may need to
+ * grab the data for the blob (or file) for our own in-core comparison.
+ * diff_filespec has data and size fields for this purpose.
+ */
+int diff_populate_filespec(struct diff_filespec *s, int size_only)
+{
+       int err = 0;
+       if (!DIFF_FILE_VALID(s))
+               die("internal error: asking to populate invalid file.");
+       if (S_ISDIR(s->mode))
+               return -1;
+
+       if (!use_size_cache)
+               size_only = 0;
+
+       if (s->data)
+               return err;
+       if (!s->sha1_valid ||
+           work_tree_matches(s->path, s->sha1)) {
+               struct stat st;
+               int fd;
+               if (lstat(s->path, &st) < 0) {
+                       if (errno == ENOENT) {
+                       err_empty:
+                               err = -1;
+                       empty:
+                               s->data = "";
+                               s->size = 0;
+                               return err;
+                       }
+               }
+               s->size = st.st_size;
+               if (!s->size)
+                       goto empty;
+               if (size_only)
+                       return 0;
+               if (S_ISLNK(st.st_mode)) {
+                       int ret;
+                       s->data = xmalloc(s->size);
+                       s->should_free = 1;
+                       ret = readlink(s->path, s->data, s->size);
+                       if (ret < 0) {
+                               free(s->data);
+                               goto err_empty;
+                       }
+                       return 0;
+               }
+               fd = open(s->path, O_RDONLY);
+               if (fd < 0)
+                       goto err_empty;
+               s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
+               close(fd);
+               if (s->data == MAP_FAILED)
+                       goto err_empty;
+               s->should_munmap = 1;
+       }
+       else {
+               char type[20];
+               struct sha1_size_cache *e;
+
+               if (size_only) {
+                       e = locate_size_cache(s->sha1, 1, 0);
+                       if (e) {
+                               s->size = e->size;
+                               return 0;
+                       }
+                       if (!sha1_object_info(s->sha1, type, &s->size))
+                               locate_size_cache(s->sha1, 0, s->size);
+               }
+               else {
+                       s->data = read_sha1_file(s->sha1, type, &s->size);
+                       s->should_free = 1;
+               }
+       }
+       return 0;
+}
+
+void diff_free_filespec_data(struct diff_filespec *s)
+{
+       if (s->should_free)
+               free(s->data);
+       else if (s->should_munmap)
+               munmap(s->data, s->size);
+       s->should_free = s->should_munmap = 0;
+       s->data = NULL;
+       free(s->cnt_data);
+       s->cnt_data = NULL;
+}
+
+static void prep_temp_blob(struct diff_tempfile *temp,
+                          void *blob,
+                          unsigned long size,
+                          const unsigned char *sha1,
+                          int mode)
+{
+       int fd;
+
+       fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
+       if (fd < 0)
+               die("unable to create temp-file");
+       if (write(fd, blob, size) != size)
+               die("unable to write temp-file");
+       close(fd);
+       temp->name = temp->tmp_path;
+       strcpy(temp->hex, sha1_to_hex(sha1));
+       temp->hex[40] = 0;
+       sprintf(temp->mode, "%06o", mode);
+}
+
+static void prepare_temp_file(const char *name,
+                             struct diff_tempfile *temp,
+                             struct diff_filespec *one)
+{
+       if (!DIFF_FILE_VALID(one)) {
+       not_a_valid_file:
+               /* A '-' entry produces this for file-2, and
+                * a '+' entry produces this for file-1.
+                */
+               temp->name = "/dev/null";
+               strcpy(temp->hex, ".");
+               strcpy(temp->mode, ".");
+               return;
+       }
+
+       if (!one->sha1_valid ||
+           work_tree_matches(name, one->sha1)) {
+               struct stat st;
+               if (lstat(name, &st) < 0) {
+                       if (errno == ENOENT)
+                               goto not_a_valid_file;
+                       die("stat(%s): %s", name, strerror(errno));
+               }
+               if (S_ISLNK(st.st_mode)) {
+                       int ret;
+                       char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
+                       if (sizeof(buf) <= st.st_size)
+                               die("symlink too long: %s", name);
+                       ret = readlink(name, buf, st.st_size);
+                       if (ret < 0)
+                               die("readlink(%s)", name);
+                       prep_temp_blob(temp, buf, st.st_size,
+                                      (one->sha1_valid ?
+                                       one->sha1 : null_sha1),
+                                      (one->sha1_valid ?
+                                       one->mode : S_IFLNK));
+               }
+               else {
+                       /* we can borrow from the file in the work tree */
+                       temp->name = name;
+                       if (!one->sha1_valid)
+                               strcpy(temp->hex, sha1_to_hex(null_sha1));
+                       else
+                               strcpy(temp->hex, sha1_to_hex(one->sha1));
+                       /* Even though we may sometimes borrow the
+                        * contents from the work tree, we always want
+                        * one->mode.  mode is trustworthy even when
+                        * !(one->sha1_valid), as long as
+                        * DIFF_FILE_VALID(one).
+                        */
+                       sprintf(temp->mode, "%06o", one->mode);
+               }
+               return;
+       }
+       else {
+               if (diff_populate_filespec(one, 0))
+                       die("cannot read data blob for %s", one->path);
+               prep_temp_blob(temp, one->data, one->size,
+                              one->sha1, one->mode);
+       }
+}
+
+static void remove_tempfile(void)
+{
+       int i;
+
+       for (i = 0; i < 2; i++)
+               if (diff_temp[i].name == diff_temp[i].tmp_path) {
+                       unlink(diff_temp[i].name);
+                       diff_temp[i].name = NULL;
+               }
+}
+
+static void remove_tempfile_on_signal(int signo)
+{
+       remove_tempfile();
+       signal(SIGINT, SIG_DFL);
+       raise(signo);
+}
+
+static int spawn_prog(const char *pgm, const char **arg)
+{
+       pid_t pid;
+       int status;
+
+       fflush(NULL);
+       pid = fork();
+       if (pid < 0)
+               die("unable to fork");
+       if (!pid) {
+               execvp(pgm, (char *const*) arg);
+               exit(255);
+       }
+
+       while (waitpid(pid, &status, 0) < 0) {
+               if (errno == EINTR)
+                       continue;
+               return -1;
+       }
+
+       /* Earlier we did not check the exit status because
+        * diff exits non-zero if files are different, and
+        * we are not interested in knowing that.  It was a
+        * mistake which made it harder to quit a diff-*
+        * session that uses the git-apply-patch-script as
+        * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
+        * should also exit non-zero only when it wants to
+        * abort the entire diff-* session.
+        */
+       if (WIFEXITED(status) && !WEXITSTATUS(status))
+               return 0;
+       return -1;
+}
+
+/* An external diff command takes:
+ *
+ * diff-cmd name infile1 infile1-sha1 infile1-mode \
+ *               infile2 infile2-sha1 infile2-mode [ rename-to ]
+ *
+ */
+static void run_external_diff(const char *pgm,
+                             const char *name,
+                             const char *other,
+                             struct diff_filespec *one,
+                             struct diff_filespec *two,
+                             const char *xfrm_msg,
+                             int complete_rewrite)
+{
+       const char *spawn_arg[10];
+       struct diff_tempfile *temp = diff_temp;
+       int retval;
+       static int atexit_asked = 0;
+       const char *othername;
+       const char **arg = &spawn_arg[0];
+
+       othername = (other? other : name);
+       if (one && two) {
+               prepare_temp_file(name, &temp[0], one);
+               prepare_temp_file(othername, &temp[1], two);
+               if (! atexit_asked &&
+                   (temp[0].name == temp[0].tmp_path ||
+                    temp[1].name == temp[1].tmp_path)) {
+                       atexit_asked = 1;
+                       atexit(remove_tempfile);
+               }
+               signal(SIGINT, remove_tempfile_on_signal);
+       }
+
+       if (one && two) {
+               *arg++ = pgm;
+               *arg++ = name;
+               *arg++ = temp[0].name;
+               *arg++ = temp[0].hex;
+               *arg++ = temp[0].mode;
+               *arg++ = temp[1].name;
+               *arg++ = temp[1].hex;
+               *arg++ = temp[1].mode;
+               if (other) {
+                       *arg++ = other;
+                       *arg++ = xfrm_msg;
+               }
+       } else {
+               *arg++ = pgm;
+               *arg++ = name;
+       }
+       *arg = NULL;
+       retval = spawn_prog(pgm, spawn_arg);
+       remove_tempfile();
+       if (retval) {
+               fprintf(stderr, "external diff died, stopping at %s.\n", name);
+               exit(1);
+       }
+}
+
+static void run_diff_cmd(const char *pgm,
+                        const char *name,
+                        const char *other,
+                        struct diff_filespec *one,
+                        struct diff_filespec *two,
+                        const char *xfrm_msg,
+                        int complete_rewrite)
+{
+       if (pgm) {
+               run_external_diff(pgm, name, other, one, two, xfrm_msg,
+                                 complete_rewrite);
+               return;
+       }
+       if (one && two)
+               builtin_diff(name, other ? other : name,
+                            one, two, xfrm_msg, complete_rewrite);
+       else
+               printf("* Unmerged path %s\n", name);
+}
+
+static void diff_fill_sha1_info(struct diff_filespec *one)
+{
+       if (DIFF_FILE_VALID(one)) {
+               if (!one->sha1_valid) {
+                       struct stat st;
+                       if (lstat(one->path, &st) < 0)
+                               die("stat %s", one->path);
+                       if (index_path(one->sha1, one->path, &st, 0))
+                               die("cannot hash %s\n", one->path);
+               }
+       }
+       else
+               memset(one->sha1, 0, 20);
+}
+
+static void run_diff(struct diff_filepair *p, struct diff_options *o)
+{
+       const char *pgm = external_diff();
+       char msg[PATH_MAX*2+300], *xfrm_msg;
+       struct diff_filespec *one;
+       struct diff_filespec *two;
+       const char *name;
+       const char *other;
+       char *name_munged, *other_munged;
+       int complete_rewrite = 0;
+       int len;
+
+       if (DIFF_PAIR_UNMERGED(p)) {
+               /* unmerged */
+               run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, 0);
+               return;
+       }
+
+       name = p->one->path;
+       other = (strcmp(name, p->two->path) ? p->two->path : NULL);
+       name_munged = quote_one(name);
+       other_munged = quote_one(other);
+       one = p->one; two = p->two;
+
+       diff_fill_sha1_info(one);
+       diff_fill_sha1_info(two);
+
+       len = 0;
+       switch (p->status) {
+       case DIFF_STATUS_COPIED:
+               len += snprintf(msg + len, sizeof(msg) - len,
+                               "similarity index %d%%\n"
+                               "copy from %s\n"
+                               "copy to %s\n",
+                               (int)(0.5 + p->score * 100.0/MAX_SCORE),
+                               name_munged, other_munged);
+               break;
+       case DIFF_STATUS_RENAMED:
+               len += snprintf(msg + len, sizeof(msg) - len,
+                               "similarity index %d%%\n"
+                               "rename from %s\n"
+                               "rename to %s\n",
+                               (int)(0.5 + p->score * 100.0/MAX_SCORE),
+                               name_munged, other_munged);
+               break;
+       case DIFF_STATUS_MODIFIED:
+               if (p->score) {
+                       len += snprintf(msg + len, sizeof(msg) - len,
+                                       "dissimilarity index %d%%\n",
+                                       (int)(0.5 + p->score *
+                                             100.0/MAX_SCORE));
+                       complete_rewrite = 1;
+                       break;
+               }
+               /* fallthru */
+       default:
+               /* nothing */
+               ;
+       }
+
+       if (memcmp(one->sha1, two->sha1, 20)) {
+               char one_sha1[41];
+               int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
+               memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
+
+               len += snprintf(msg + len, sizeof(msg) - len,
+                               "index %.*s..%.*s",
+                               abbrev, one_sha1, abbrev,
+                               sha1_to_hex(two->sha1));
+               if (one->mode == two->mode)
+                       len += snprintf(msg + len, sizeof(msg) - len,
+                                       " %06o", one->mode);
+               len += snprintf(msg + len, sizeof(msg) - len, "\n");
+       }
+
+       if (len)
+               msg[--len] = 0;
+       xfrm_msg = len ? msg : NULL;
+
+       if (!pgm &&
+           DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
+           (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
+               /* a filepair that changes between file and symlink
+                * needs to be split into deletion and creation.
+                */
+               struct diff_filespec *null = alloc_filespec(two->path);
+               run_diff_cmd(NULL, name, other, one, null, xfrm_msg, 0);
+               free(null);
+               null = alloc_filespec(one->path);
+               run_diff_cmd(NULL, name, other, null, two, xfrm_msg, 0);
+               free(null);
+       }
+       else
+               run_diff_cmd(pgm, name, other, one, two, xfrm_msg,
+                            complete_rewrite);
+
+       free(name_munged);
+       free(other_munged);
+}
+
+static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
+               struct diffstat_t *diffstat)
+{
+       const char *name;
+       const char *other;
+
+       if (DIFF_PAIR_UNMERGED(p)) {
+               /* unmerged */
+               builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat);
+               return;
+       }
+
+       name = p->one->path;
+       other = (strcmp(name, p->two->path) ? p->two->path : NULL);
+
+       diff_fill_sha1_info(p->one);
+       diff_fill_sha1_info(p->two);
+
+       builtin_diffstat(name, other, p->one, p->two, diffstat);
+}
+
+void diff_setup(struct diff_options *options)
+{
+       memset(options, 0, sizeof(*options));
+       options->output_format = DIFF_FORMAT_RAW;
+       options->line_termination = '\n';
+       options->break_opt = -1;
+       options->rename_limit = -1;
+
+       options->change = diff_change;
+       options->add_remove = diff_addremove;
+}
+
+int diff_setup_done(struct diff_options *options)
+{
+       if ((options->find_copies_harder &&
+            options->detect_rename != DIFF_DETECT_COPY) ||
+           (0 <= options->rename_limit && !options->detect_rename))
+               return -1;
+
+       /*
+        * These cases always need recursive; we do not drop caller-supplied
+        * recursive bits for other formats here.
+        */
+       if ((options->output_format == DIFF_FORMAT_PATCH) ||
+           (options->output_format == DIFF_FORMAT_DIFFSTAT))
+               options->recursive = 1;
+
+       if (options->detect_rename && options->rename_limit < 0)
+               options->rename_limit = diff_rename_limit_default;
+       if (options->setup & DIFF_SETUP_USE_CACHE) {
+               if (!active_cache)
+                       /* read-cache does not die even when it fails
+                        * so it is safe for us to do this here.  Also
+                        * it does not smudge active_cache or active_nr
+                        * when it fails, so we do not have to worry about
+                        * cleaning it up ourselves either.
+                        */
+                       read_cache();
+       }
+       if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
+               use_size_cache = 1;
+       if (options->abbrev <= 0 || 40 < options->abbrev)
+               options->abbrev = 40; /* full */
+
+       return 0;
+}
+
+int diff_opt_parse(struct diff_options *options, const char **av, int ac)
+{
+       const char *arg = av[0];
+       if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
+               options->output_format = DIFF_FORMAT_PATCH;
+       else if (!strcmp(arg, "--patch-with-raw")) {
+               options->output_format = DIFF_FORMAT_PATCH;
+               options->with_raw = 1;
+       }
+       else if (!strcmp(arg, "--stat"))
+               options->output_format = DIFF_FORMAT_DIFFSTAT;
+       else if (!strcmp(arg, "--patch-with-stat")) {
+               options->output_format = DIFF_FORMAT_PATCH;
+               options->with_stat = 1;
+       }
+       else if (!strcmp(arg, "-z"))
+               options->line_termination = 0;
+       else if (!strncmp(arg, "-l", 2))
+               options->rename_limit = strtoul(arg+2, NULL, 10);
+       else if (!strcmp(arg, "--full-index"))
+               options->full_index = 1;
+       else if (!strcmp(arg, "--name-only"))
+               options->output_format = DIFF_FORMAT_NAME;
+       else if (!strcmp(arg, "--name-status"))
+               options->output_format = DIFF_FORMAT_NAME_STATUS;
+       else if (!strcmp(arg, "-R"))
+               options->reverse_diff = 1;
+       else if (!strncmp(arg, "-S", 2))
+               options->pickaxe = arg + 2;
+       else if (!strcmp(arg, "-s"))
+               options->output_format = DIFF_FORMAT_NO_OUTPUT;
+       else if (!strncmp(arg, "-O", 2))
+               options->orderfile = arg + 2;
+       else if (!strncmp(arg, "--diff-filter=", 14))
+               options->filter = arg + 14;
+       else if (!strcmp(arg, "--pickaxe-all"))
+               options->pickaxe_opts = DIFF_PICKAXE_ALL;
+       else if (!strcmp(arg, "--pickaxe-regex"))
+               options->pickaxe_opts = DIFF_PICKAXE_REGEX;
+       else if (!strncmp(arg, "-B", 2)) {
+               if ((options->break_opt =
+                    diff_scoreopt_parse(arg)) == -1)
+                       return -1;
+       }
+       else if (!strncmp(arg, "-M", 2)) {
+               if ((options->rename_score =
+                    diff_scoreopt_parse(arg)) == -1)
+                       return -1;
+               options->detect_rename = DIFF_DETECT_RENAME;
+       }
+       else if (!strncmp(arg, "-C", 2)) {
+               if ((options->rename_score =
+                    diff_scoreopt_parse(arg)) == -1)
+                       return -1;
+               options->detect_rename = DIFF_DETECT_COPY;
+       }
+       else if (!strcmp(arg, "--find-copies-harder"))
+               options->find_copies_harder = 1;
+       else if (!strcmp(arg, "--abbrev"))
+               options->abbrev = DEFAULT_ABBREV;
+       else if (!strncmp(arg, "--abbrev=", 9)) {
+               options->abbrev = strtoul(arg + 9, NULL, 10);
+               if (options->abbrev < MINIMUM_ABBREV)
+                       options->abbrev = MINIMUM_ABBREV;
+               else if (40 < options->abbrev)
+                       options->abbrev = 40;
+       }
+       else
+               return 0;
+       return 1;
+}
+
+static int parse_num(const char **cp_p)
+{
+       unsigned long num, scale;
+       int ch, dot;
+       const char *cp = *cp_p;
+
+       num = 0;
+       scale = 1;
+       dot = 0;
+       for(;;) {
+               ch = *cp;
+               if ( !dot && ch == '.' ) {
+                       scale = 1;
+                       dot = 1;
+               } else if ( ch == '%' ) {
+                       scale = dot ? scale*100 : 100;
+                       cp++;   /* % is always at the end */
+                       break;
+               } else if ( ch >= '0' && ch <= '9' ) {
+                       if ( scale < 100000 ) {
+                               scale *= 10;
+                               num = (num*10) + (ch-'0');
+                       }
+               } else {
+                       break;
+               }
+               cp++;
+       }
+       *cp_p = cp;
+
+       /* user says num divided by scale and we say internally that
+        * is MAX_SCORE * num / scale.
+        */
+       return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
+}
+
+int diff_scoreopt_parse(const char *opt)
+{
+       int opt1, opt2, cmd;
+
+       if (*opt++ != '-')
+               return -1;
+       cmd = *opt++;
+       if (cmd != 'M' && cmd != 'C' && cmd != 'B')
+               return -1; /* that is not a -M, -C nor -B option */
+
+       opt1 = parse_num(&opt);
+       if (cmd != 'B')
+               opt2 = 0;
+       else {
+               if (*opt == 0)
+                       opt2 = 0;
+               else if (*opt != '/')
+                       return -1; /* we expect -B80/99 or -B80 */
+               else {
+                       opt++;
+                       opt2 = parse_num(&opt);
+               }
+       }
+       if (*opt != 0)
+               return -1;
+       return opt1 | (opt2 << 16);
+}
+
+struct diff_queue_struct diff_queued_diff;
+
+void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
+{
+       if (queue->alloc <= queue->nr) {
+               queue->alloc = alloc_nr(queue->alloc);
+               queue->queue = xrealloc(queue->queue,
+                                       sizeof(dp) * queue->alloc);
+       }
+       queue->queue[queue->nr++] = dp;
+}
+
+struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
+                                struct diff_filespec *one,
+                                struct diff_filespec *two)
+{
+       struct diff_filepair *dp = xmalloc(sizeof(*dp));
+       dp->one = one;
+       dp->two = two;
+       dp->score = 0;
+       dp->status = 0;
+       dp->source_stays = 0;
+       dp->broken_pair = 0;
+       if (queue)
+               diff_q(queue, dp);
+       return dp;
+}
+
+void diff_free_filepair(struct diff_filepair *p)
+{
+       diff_free_filespec_data(p->one);
+       diff_free_filespec_data(p->two);
+       free(p->one);
+       free(p->two);
+       free(p);
+}
+
+/* This is different from find_unique_abbrev() in that
+ * it stuffs the result with dots for alignment.
+ */
+const char *diff_unique_abbrev(const unsigned char *sha1, int len)
+{
+       int abblen;
+       const char *abbrev;
+       if (len == 40)
+               return sha1_to_hex(sha1);
+
+       abbrev = find_unique_abbrev(sha1, len);
+       if (!abbrev)
+               return sha1_to_hex(sha1);
+       abblen = strlen(abbrev);
+       if (abblen < 37) {
+               static char hex[41];
+               if (len < abblen && abblen <= len + 2)
+                       sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
+               else
+                       sprintf(hex, "%s...", abbrev);
+               return hex;
+       }
+       return sha1_to_hex(sha1);
+}
+
+static void diff_flush_raw(struct diff_filepair *p,
+                          int line_termination,
+                          int inter_name_termination,
+                          struct diff_options *options,
+                          int output_format)
+{
+       int two_paths;
+       char status[10];
+       int abbrev = options->abbrev;
+       const char *path_one, *path_two;
+
+       path_one = p->one->path;
+       path_two = p->two->path;
+       if (line_termination) {
+               path_one = quote_one(path_one);
+               path_two = quote_one(path_two);
+       }
+
+       if (p->score)
+               sprintf(status, "%c%03d", p->status,
+                       (int)(0.5 + p->score * 100.0/MAX_SCORE));
+       else {
+               status[0] = p->status;
+               status[1] = 0;
+       }
+       switch (p->status) {
+       case DIFF_STATUS_COPIED:
+       case DIFF_STATUS_RENAMED:
+               two_paths = 1;
+               break;
+       case DIFF_STATUS_ADDED:
+       case DIFF_STATUS_DELETED:
+               two_paths = 0;
+               break;
+       default:
+               two_paths = 0;
+               break;
+       }
+       if (output_format != DIFF_FORMAT_NAME_STATUS) {
+               printf(":%06o %06o %s ",
+                      p->one->mode, p->two->mode,
+                      diff_unique_abbrev(p->one->sha1, abbrev));
+               printf("%s ",
+                      diff_unique_abbrev(p->two->sha1, abbrev));
+       }
+       printf("%s%c%s", status, inter_name_termination, path_one);
+       if (two_paths)
+               printf("%c%s", inter_name_termination, path_two);
+       putchar(line_termination);
+       if (path_one != p->one->path)
+               free((void*)path_one);
+       if (path_two != p->two->path)
+               free((void*)path_two);
+}
+
+static void diff_flush_name(struct diff_filepair *p,
+                           int inter_name_termination,
+                           int line_termination)
+{
+       char *path = p->two->path;
+
+       if (line_termination)
+               path = quote_one(p->two->path);
+       else
+               path = p->two->path;
+       printf("%s%c", path, line_termination);
+       if (p->two->path != path)
+               free(path);
+}
+
+int diff_unmodified_pair(struct diff_filepair *p)
+{
+       /* This function is written stricter than necessary to support
+        * the currently implemented transformers, but the idea is to
+        * let transformers to produce diff_filepairs any way they want,
+        * and filter and clean them up here before producing the output.
+        */
+       struct diff_filespec *one, *two;
+
+       if (DIFF_PAIR_UNMERGED(p))
+               return 0; /* unmerged is interesting */
+
+       one = p->one;
+       two = p->two;
+
+       /* deletion, addition, mode or type change
+        * and rename are all interesting.
+        */
+       if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
+           DIFF_PAIR_MODE_CHANGED(p) ||
+           strcmp(one->path, two->path))
+               return 0;
+
+       /* both are valid and point at the same path.  that is, we are
+        * dealing with a change.
+        */
+       if (one->sha1_valid && two->sha1_valid &&
+           !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
+               return 1; /* no change */
+       if (!one->sha1_valid && !two->sha1_valid)
+               return 1; /* both look at the same file on the filesystem. */
+       return 0;
+}
+
+static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
+{
+       if (diff_unmodified_pair(p))
+               return;
+
+       if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
+           (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
+               return; /* no tree diffs in patch format */
+
+       run_diff(p, o);
+}
+
+static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
+               struct diffstat_t *diffstat)
+{
+       if (diff_unmodified_pair(p))
+               return;
+
+       if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
+           (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
+               return; /* no tree diffs in patch format */
+
+       run_diffstat(p, o, diffstat);
+}
+
+int diff_queue_is_empty(void)
+{
+       struct diff_queue_struct *q = &diff_queued_diff;
+       int i;
+       for (i = 0; i < q->nr; i++)
+               if (!diff_unmodified_pair(q->queue[i]))
+                       return 0;
+       return 1;
+}
+
+#if DIFF_DEBUG
+void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
+{
+       fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
+               x, one ? one : "",
+               s->path,
+               DIFF_FILE_VALID(s) ? "valid" : "invalid",
+               s->mode,
+               s->sha1_valid ? sha1_to_hex(s->sha1) : "");
+       fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
+               x, one ? one : "",
+               s->size, s->xfrm_flags);
+}
+
+void diff_debug_filepair(const struct diff_filepair *p, int i)
+{
+       diff_debug_filespec(p->one, i, "one");
+       diff_debug_filespec(p->two, i, "two");
+       fprintf(stderr, "score %d, status %c stays %d broken %d\n",
+               p->score, p->status ? p->status : '?',
+               p->source_stays, p->broken_pair);
+}
+
+void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
+{
+       int i;
+       if (msg)
+               fprintf(stderr, "%s\n", msg);
+       fprintf(stderr, "q->nr = %d\n", q->nr);
+       for (i = 0; i < q->nr; i++) {
+               struct diff_filepair *p = q->queue[i];
+               diff_debug_filepair(p, i);
+       }
+}
+#endif
+
+static void diff_resolve_rename_copy(void)
+{
+       int i, j;
+       struct diff_filepair *p, *pp;
+       struct diff_queue_struct *q = &diff_queued_diff;
+
+       diff_debug_queue("resolve-rename-copy", q);
+
+       for (i = 0; i < q->nr; i++) {
+               p = q->queue[i];
+               p->status = 0; /* undecided */
+               if (DIFF_PAIR_UNMERGED(p))
+                       p->status = DIFF_STATUS_UNMERGED;
+               else if (!DIFF_FILE_VALID(p->one))
+                       p->status = DIFF_STATUS_ADDED;
+               else if (!DIFF_FILE_VALID(p->two))
+                       p->status = DIFF_STATUS_DELETED;
+               else if (DIFF_PAIR_TYPE_CHANGED(p))
+                       p->status = DIFF_STATUS_TYPE_CHANGED;
+
+               /* from this point on, we are dealing with a pair
+                * whose both sides are valid and of the same type, i.e.
+                * either in-place edit or rename/copy edit.
+                */
+               else if (DIFF_PAIR_RENAME(p)) {
+                       if (p->source_stays) {
+                               p->status = DIFF_STATUS_COPIED;
+                               continue;
+                       }
+                       /* See if there is some other filepair that
+                        * copies from the same source as us.  If so
+                        * we are a copy.  Otherwise we are either a
+                        * copy if the path stays, or a rename if it
+                        * does not, but we already handled "stays" case.
+                        */
+                       for (j = i + 1; j < q->nr; j++) {
+                               pp = q->queue[j];
+                               if (strcmp(pp->one->path, p->one->path))
+                                       continue; /* not us */
+                               if (!DIFF_PAIR_RENAME(pp))
+                                       continue; /* not a rename/copy */
+                               /* pp is a rename/copy from the same source */
+                               p->status = DIFF_STATUS_COPIED;
+                               break;
+                       }
+                       if (!p->status)
+                               p->status = DIFF_STATUS_RENAMED;
+               }
+               else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
+                        p->one->mode != p->two->mode)
+                       p->status = DIFF_STATUS_MODIFIED;
+               else {
+                       /* This is a "no-change" entry and should not
+                        * happen anymore, but prepare for broken callers.
+                        */
+                       error("feeding unmodified %s to diffcore",
+                             p->one->path);
+                       p->status = DIFF_STATUS_UNKNOWN;
+               }
+       }
+       diff_debug_queue("resolve-rename-copy done", q);
+}
+
+static void flush_one_pair(struct diff_filepair *p,
+                          int diff_output_format,
+                          struct diff_options *options,
+                          struct diffstat_t *diffstat)
+{
+       int inter_name_termination = '\t';
+       int line_termination = options->line_termination;
+       if (!line_termination)
+               inter_name_termination = 0;
+
+       switch (p->status) {
+       case DIFF_STATUS_UNKNOWN:
+               break;
+       case 0:
+               die("internal error in diff-resolve-rename-copy");
+               break;
+       default:
+               switch (diff_output_format) {
+               case DIFF_FORMAT_DIFFSTAT:
+                       diff_flush_stat(p, options, diffstat);
+                       break;
+               case DIFF_FORMAT_PATCH:
+                       diff_flush_patch(p, options);
+                       break;
+               case DIFF_FORMAT_RAW:
+               case DIFF_FORMAT_NAME_STATUS:
+                       diff_flush_raw(p, line_termination,
+                                      inter_name_termination,
+                                      options, diff_output_format);
+                       break;
+               case DIFF_FORMAT_NAME:
+                       diff_flush_name(p,
+                                       inter_name_termination,
+                                       line_termination);
+                       break;
+               case DIFF_FORMAT_NO_OUTPUT:
+                       break;
+               }
+       }
+}
+
+void diff_flush(struct diff_options *options)
+{
+       struct diff_queue_struct *q = &diff_queued_diff;
+       int i;
+       int diff_output_format = options->output_format;
+       struct diffstat_t *diffstat = NULL;
+
+       if (diff_output_format == DIFF_FORMAT_DIFFSTAT || options->with_stat) {
+               diffstat = xcalloc(sizeof (struct diffstat_t), 1);
+               diffstat->xm.consume = diffstat_consume;
+       }
+
+       if (options->with_raw) {
+               for (i = 0; i < q->nr; i++) {
+                       struct diff_filepair *p = q->queue[i];
+                       flush_one_pair(p, DIFF_FORMAT_RAW, options, NULL);
+               }
+               putchar(options->line_termination);
+       }
+       if (options->with_stat) {
+               for (i = 0; i < q->nr; i++) {
+                       struct diff_filepair *p = q->queue[i];
+                       flush_one_pair(p, DIFF_FORMAT_DIFFSTAT, options,
+                                       diffstat);
+               }
+               show_stats(diffstat);
+               free(diffstat);
+               diffstat = NULL;
+               putchar(options->line_termination);
+       }
+       for (i = 0; i < q->nr; i++) {
+               struct diff_filepair *p = q->queue[i];
+               flush_one_pair(p, diff_output_format, options, diffstat);
+               diff_free_filepair(p);
+       }
+
+       if (diffstat) {
+               show_stats(diffstat);
+               free(diffstat);
+       }
+
+       free(q->queue);
+       q->queue = NULL;
+       q->nr = q->alloc = 0;
+}
+
+static void diffcore_apply_filter(const char *filter)
+{
+       int i;
+       struct diff_queue_struct *q = &diff_queued_diff;
+       struct diff_queue_struct outq;
+       outq.queue = NULL;
+       outq.nr = outq.alloc = 0;
+
+       if (!filter)
+               return;
+
+       if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
+               int found;
+               for (i = found = 0; !found && i < q->nr; i++) {
+                       struct diff_filepair *p = q->queue[i];
+                       if (((p->status == DIFF_STATUS_MODIFIED) &&
+                            ((p->score &&
+                              strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
+                             (!p->score &&
+                              strchr(filter, DIFF_STATUS_MODIFIED)))) ||
+                           ((p->status != DIFF_STATUS_MODIFIED) &&
+                            strchr(filter, p->status)))
+                               found++;
+               }
+               if (found)
+                       return;
+
+               /* otherwise we will clear the whole queue
+                * by copying the empty outq at the end of this
+                * function, but first clear the current entries
+                * in the queue.
+                */
+               for (i = 0; i < q->nr; i++)
+                       diff_free_filepair(q->queue[i]);
+       }
+       else {
+               /* Only the matching ones */
+               for (i = 0; i < q->nr; i++) {
+                       struct diff_filepair *p = q->queue[i];
+
+                       if (((p->status == DIFF_STATUS_MODIFIED) &&
+                            ((p->score &&
+                              strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
+                             (!p->score &&
+                              strchr(filter, DIFF_STATUS_MODIFIED)))) ||
+                           ((p->status != DIFF_STATUS_MODIFIED) &&
+                            strchr(filter, p->status)))
+                               diff_q(&outq, p);
+                       else
+                               diff_free_filepair(p);
+               }
+       }
+       free(q->queue);
+       *q = outq;
+}
+
+void diffcore_std(struct diff_options *options)
+{
+       if (options->break_opt != -1)
+               diffcore_break(options->break_opt);
+       if (options->detect_rename)
+               diffcore_rename(options);
+       if (options->break_opt != -1)
+               diffcore_merge_broken();
+       if (options->pickaxe)
+               diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
+       if (options->orderfile)
+               diffcore_order(options->orderfile);
+       diff_resolve_rename_copy();
+       diffcore_apply_filter(options->filter);
+}
+
+
+void diffcore_std_no_resolve(struct diff_options *options)
+{
+       if (options->pickaxe)
+               diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
+       if (options->orderfile)
+               diffcore_order(options->orderfile);
+       diffcore_apply_filter(options->filter);
+}
+
+void diff_addremove(struct diff_options *options,
+                   int addremove, unsigned mode,
+                   const unsigned char *sha1,
+                   const char *base, const char *path)
+{
+       char concatpath[PATH_MAX];
+       struct diff_filespec *one, *two;
+
+       /* This may look odd, but it is a preparation for
+        * feeding "there are unchanged files which should
+        * not produce diffs, but when you are doing copy
+        * detection you would need them, so here they are"
+        * entries to the diff-core.  They will be prefixed
+        * with something like '=' or '*' (I haven't decided
+        * which but should not make any difference).
+        * Feeding the same new and old to diff_change() 
+        * also has the same effect.
+        * Before the final output happens, they are pruned after
+        * merged into rename/copy pairs as appropriate.
+        */
+       if (options->reverse_diff)
+               addremove = (addremove == '+' ? '-' :
+                            addremove == '-' ? '+' : addremove);
+
+       if (!path) path = "";
+       sprintf(concatpath, "%s%s", base, path);
+       one = alloc_filespec(concatpath);
+       two = alloc_filespec(concatpath);
+
+       if (addremove != '+')
+               fill_filespec(one, sha1, mode);
+       if (addremove != '-')
+               fill_filespec(two, sha1, mode);
+
+       diff_queue(&diff_queued_diff, one, two);
+}
+
+void diff_change(struct diff_options *options,
+                unsigned old_mode, unsigned new_mode,
+                const unsigned char *old_sha1,
+                const unsigned char *new_sha1,
+                const char *base, const char *path) 
+{
+       char concatpath[PATH_MAX];
+       struct diff_filespec *one, *two;
+
+       if (options->reverse_diff) {
+               unsigned tmp;
+               const unsigned char *tmp_c;
+               tmp = old_mode; old_mode = new_mode; new_mode = tmp;
+               tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
+       }
+       if (!path) path = "";
+       sprintf(concatpath, "%s%s", base, path);
+       one = alloc_filespec(concatpath);
+       two = alloc_filespec(concatpath);
+       fill_filespec(one, old_sha1, old_mode);
+       fill_filespec(two, new_sha1, new_mode);
+
+       diff_queue(&diff_queued_diff, one, two);
+}
+
+void diff_unmerge(struct diff_options *options,
+                 const char *path)
+{
+       struct diff_filespec *one, *two;
+       one = alloc_filespec(path);
+       two = alloc_filespec(path);
+       diff_queue(&diff_queued_diff, one, two);
+}

diff --git a/diff.c b/diff.c
deleted file mode 100644 (file)
index 0a832c3..0000000
--- a/diff.c
+++ /dev/null
@@ -1,1736 +0,0 @@
-/*
- * Copyright (C) 2005 Junio C Hamano
- */
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <signal.h>
-#include "cache.h"
-#include "quote.h"
-#include "diff.h"
-#include "diffcore.h"
-#include "xdiff-interface.h"
-
-static int use_size_cache;
-
-int diff_rename_limit_default = -1;
-
-int git_diff_config(const char *var, const char *value)
-{
-       if (!strcmp(var, "diff.renamelimit")) {
-               diff_rename_limit_default = git_config_int(var, value);
-               return 0;
-       }
-
-       return git_default_config(var, value);
-}
-
-static char *quote_one(const char *str)
-{
-       int needlen;
-       char *xp;
-
-       if (!str)
-               return NULL;
-       needlen = quote_c_style(str, NULL, NULL, 0);
-       if (!needlen)
-               return strdup(str);
-       xp = xmalloc(needlen + 1);
-       quote_c_style(str, xp, NULL, 0);
-       return xp;
-}
-
-static char *quote_two(const char *one, const char *two)
-{
-       int need_one = quote_c_style(one, NULL, NULL, 1);
-       int need_two = quote_c_style(two, NULL, NULL, 1);
-       char *xp;
-
-       if (need_one + need_two) {
-               if (!need_one) need_one = strlen(one);
-               if (!need_two) need_one = strlen(two);
-
-               xp = xmalloc(need_one + need_two + 3);
-               xp[0] = '"';
-               quote_c_style(one, xp + 1, NULL, 1);
-               quote_c_style(two, xp + need_one + 1, NULL, 1);
-               strcpy(xp + need_one + need_two + 1, "\"");
-               return xp;
-       }
-       need_one = strlen(one);
-       need_two = strlen(two);
-       xp = xmalloc(need_one + need_two + 1);
-       strcpy(xp, one);
-       strcpy(xp + need_one, two);
-       return xp;
-}
-
-static const char *external_diff(void)
-{
-       static const char *external_diff_cmd = NULL;
-       static int done_preparing = 0;
-
-       if (done_preparing)
-               return external_diff_cmd;
-       external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
-       done_preparing = 1;
-       return external_diff_cmd;
-}
-
-#define TEMPFILE_PATH_LEN              50
-
-static struct diff_tempfile {
-       const char *name; /* filename external diff should read from */
-       char hex[41];
-       char mode[10];
-       char tmp_path[TEMPFILE_PATH_LEN];
-} diff_temp[2];
-
-static int count_lines(const char *data, int size)
-{
-       int count, ch, completely_empty = 1, nl_just_seen = 0;
-       count = 0;
-       while (0 < size--) {
-               ch = *data++;
-               if (ch == '\n') {
-                       count++;
-                       nl_just_seen = 1;
-                       completely_empty = 0;
-               }
-               else {
-                       nl_just_seen = 0;
-                       completely_empty = 0;
-               }
-       }
-       if (completely_empty)
-               return 0;
-       if (!nl_just_seen)
-               count++; /* no trailing newline */
-       return count;
-}
-
-static void print_line_count(int count)
-{
-       switch (count) {
-       case 0:
-               printf("0,0");
-               break;
-       case 1:
-               printf("1");
-               break;
-       default:
-               printf("1,%d", count);
-               break;
-       }
-}
-
-static void copy_file(int prefix, const char *data, int size)
-{
-       int ch, nl_just_seen = 1;
-       while (0 < size--) {
-               ch = *data++;
-               if (nl_just_seen)
-                       putchar(prefix);
-               putchar(ch);
-               if (ch == '\n')
-                       nl_just_seen = 1;
-               else
-                       nl_just_seen = 0;
-       }
-       if (!nl_just_seen)
-               printf("\n\\ No newline at end of file\n");
-}
-
-static void emit_rewrite_diff(const char *name_a,
-                             const char *name_b,
-                             struct diff_filespec *one,
-                             struct diff_filespec *two)
-{
-       int lc_a, lc_b;
-       diff_populate_filespec(one, 0);
-       diff_populate_filespec(two, 0);
-       lc_a = count_lines(one->data, one->size);
-       lc_b = count_lines(two->data, two->size);
-       printf("--- %s\n+++ %s\n@@ -", name_a, name_b);
-       print_line_count(lc_a);
-       printf(" +");
-       print_line_count(lc_b);
-       printf(" @@\n");
-       if (lc_a)
-               copy_file('-', one->data, one->size);
-       if (lc_b)
-               copy_file('+', two->data, two->size);
-}
-
-static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
-{
-       if (!DIFF_FILE_VALID(one)) {
-               mf->ptr = ""; /* does not matter */
-               mf->size = 0;
-               return 0;
-       }
-       else if (diff_populate_filespec(one, 0))
-               return -1;
-       mf->ptr = one->data;
-       mf->size = one->size;
-       return 0;
-}
-
-struct emit_callback {
-       const char **label_path;
-};
-
-static int fn_out(void *priv, mmbuffer_t *mb, int nbuf)
-{
-       int i;
-       struct emit_callback *ecbdata = priv;
-
-       if (ecbdata->label_path[0]) {
-               printf("--- %s\n", ecbdata->label_path[0]);
-               printf("+++ %s\n", ecbdata->label_path[1]);
-               ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
-       }
-       for (i = 0; i < nbuf; i++)
-               if (!fwrite(mb[i].ptr, mb[i].size, 1, stdout))
-                       return -1;
-       return 0;
-}
-
-struct diffstat_t {
-       struct xdiff_emit_state xm;
-
-       int nr;
-       int alloc;
-       struct diffstat_file {
-               char *name;
-               unsigned is_unmerged:1;
-               unsigned is_binary:1;
-               unsigned int added, deleted;
-       } **files;
-};
-
-static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
-               const char *name)
-{
-       struct diffstat_file *x;
-       x = xcalloc(sizeof (*x), 1);
-       if (diffstat->nr == diffstat->alloc) {
-               diffstat->alloc = alloc_nr(diffstat->alloc);
-               diffstat->files = xrealloc(diffstat->files,
-                               diffstat->alloc * sizeof(x));
-       }
-       diffstat->files[diffstat->nr++] = x;
-       x->name = strdup(name);
-       return x;
-}
-
-static void diffstat_consume(void *priv, char *line, unsigned long len)
-{
-       struct diffstat_t *diffstat = priv;
-       struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
-
-       if (line[0] == '+')
-               x->added++;
-       else if (line[0] == '-')
-               x->deleted++;
-}
-
-static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
-static const char minuses[]= "----------------------------------------------------------------------";
-
-static void show_stats(struct diffstat_t* data)
-{
-       char *prefix = "";
-       int i, len, add, del, total, adds = 0, dels = 0;
-       int max, max_change = 0, max_len = 0;
-       int total_files = data->nr;
-
-       if (data->nr == 0)
-               return;
-
-       for (i = 0; i < data->nr; i++) {
-               struct diffstat_file *file = data->files[i];
-
-               len = strlen(file->name);
-               if (max_len < len)
-                       max_len = len;
-
-               if (file->is_binary || file->is_unmerged)
-                       continue;
-               if (max_change < file->added + file->deleted)
-                       max_change = file->added + file->deleted;
-       }
-
-       for (i = 0; i < data->nr; i++) {
-               char *name = data->files[i]->name;
-               int added = data->files[i]->added;
-               int deleted = data->files[i]->deleted;
-
-               if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
-                       char *qname = xmalloc(len + 1);
-                       quote_c_style(name, qname, NULL, 0);
-                       free(name);
-                       data->files[i]->name = name = qname;
-               }
-
-               /*
-                * "scale" the filename
-                */
-               len = strlen(name);
-               max = max_len;
-               if (max > 50)
-                       max = 50;
-               if (len > max) {
-                       char *slash;
-                       prefix = "...";
-                       max -= 3;
-                       name += len - max;
-                       slash = strchr(name, '/');
-                       if (slash)
-                               name = slash;
-               }
-               len = max;
-
-               /*
-                * scale the add/delete
-                */
-               max = max_change;
-               if (max + len > 70)
-                       max = 70 - len;
-
-               if (data->files[i]->is_binary) {
-                       printf(" %s%-*s |  Bin\n", prefix, len, name);
-                       goto free_diffstat_file;
-               }
-               else if (data->files[i]->is_unmerged) {
-                       printf(" %s%-*s |  Unmerged\n", prefix, len, name);
-                       goto free_diffstat_file;
-               }
-               else if (added + deleted == 0) {
-                       total_files--;
-                       goto free_diffstat_file;
-               }
-
-               add = added;
-               del = deleted;
-               total = add + del;
-               adds += add;
-               dels += del;
-
-               if (max_change > 0) {
-                       total = (total * max + max_change / 2) / max_change;
-                       add = (add * max + max_change / 2) / max_change;
-                       del = total - add;
-               }
-               printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
-                               len, name, added + deleted,
-                               add, pluses, del, minuses);
-       free_diffstat_file:
-               free(data->files[i]->name);
-               free(data->files[i]);
-       }
-       free(data->files);
-       printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
-                       total_files, adds, dels);
-}
-
-#define FIRST_FEW_BYTES 8000
-static int mmfile_is_binary(mmfile_t *mf)
-{
-       long sz = mf->size;
-       if (FIRST_FEW_BYTES < sz)
-               sz = FIRST_FEW_BYTES;
-       if (memchr(mf->ptr, 0, sz))
-               return 1;
-       return 0;
-}
-
-static void builtin_diff(const char *name_a,
-                        const char *name_b,
-                        struct diff_filespec *one,
-                        struct diff_filespec *two,
-                        const char *xfrm_msg,
-                        int complete_rewrite)
-{
-       mmfile_t mf1, mf2;
-       const char *lbl[2];
-       char *a_one, *b_two;
-
-       a_one = quote_two("a/", name_a);
-       b_two = quote_two("b/", name_b);
-       lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
-       lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
-       printf("diff --git %s %s\n", a_one, b_two);
-       if (lbl[0][0] == '/') {
-               /* /dev/null */
-               printf("new file mode %06o\n", two->mode);
-               if (xfrm_msg && xfrm_msg[0])
-                       puts(xfrm_msg);
-       }
-       else if (lbl[1][0] == '/') {
-               printf("deleted file mode %06o\n", one->mode);
-               if (xfrm_msg && xfrm_msg[0])
-                       puts(xfrm_msg);
-       }
-       else {
-               if (one->mode != two->mode) {
-                       printf("old mode %06o\n", one->mode);
-                       printf("new mode %06o\n", two->mode);
-               }
-               if (xfrm_msg && xfrm_msg[0])
-                       puts(xfrm_msg);
-               /*
-                * we do not run diff between different kind
-                * of objects.
-                */
-               if ((one->mode ^ two->mode) & S_IFMT)
-                       goto free_ab_and_return;
-               if (complete_rewrite) {
-                       emit_rewrite_diff(name_a, name_b, one, two);
-                       goto free_ab_and_return;
-               }
-       }
-
-       if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
-               die("unable to read files to diff");
-
-       if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
-               printf("Binary files %s and %s differ\n", lbl[0], lbl[1]);
-       else {
-               /* Crazy xdl interfaces.. */
-               const char *diffopts = getenv("GIT_DIFF_OPTS");
-               xpparam_t xpp;
-               xdemitconf_t xecfg;
-               xdemitcb_t ecb;
-               struct emit_callback ecbdata;
-
-               ecbdata.label_path = lbl;
-               xpp.flags = XDF_NEED_MINIMAL;
-               xecfg.ctxlen = 3;
-               xecfg.flags = XDL_EMIT_FUNCNAMES;
-               if (!diffopts)
-                       ;
-               else if (!strncmp(diffopts, "--unified=", 10))
-                       xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
-               else if (!strncmp(diffopts, "-u", 2))
-                       xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
-               ecb.outf = fn_out;
-               ecb.priv = &ecbdata;
-               xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
-       }
-
- free_ab_and_return:
-       free(a_one);
-       free(b_two);
-       return;
-}
-
-static void builtin_diffstat(const char *name_a, const char *name_b,
-               struct diff_filespec *one, struct diff_filespec *two,
-               struct diffstat_t *diffstat)
-{
-       mmfile_t mf1, mf2;
-       struct diffstat_file *data;
-
-       data = diffstat_add(diffstat, name_a ? name_a : name_b);
-
-       if (!one || !two) {
-               data->is_unmerged = 1;
-               return;
-       }
-
-       if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
-               die("unable to read files to diff");
-
-       if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
-               data->is_binary = 1;
-       else {
-               /* Crazy xdl interfaces.. */
-               xpparam_t xpp;
-               xdemitconf_t xecfg;
-               xdemitcb_t ecb;
-
-               xpp.flags = XDF_NEED_MINIMAL;
-               xecfg.ctxlen = 0;
-               xecfg.flags = 0;
-               ecb.outf = xdiff_outf;
-               ecb.priv = diffstat;
-               xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
-       }
-}
-
-struct diff_filespec *alloc_filespec(const char *path)
-{
-       int namelen = strlen(path);
-       struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
-
-       memset(spec, 0, sizeof(*spec));
-       spec->path = (char *)(spec + 1);
-       memcpy(spec->path, path, namelen+1);
-       return spec;
-}
-
-void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
-                  unsigned short mode)
-{
-       if (mode) {
-               spec->mode = canon_mode(mode);
-               memcpy(spec->sha1, sha1, 20);
-               spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
-       }
-}
-
-/*
- * Given a name and sha1 pair, if the dircache tells us the file in
- * the work tree has that object contents, return true, so that
- * prepare_temp_file() does not have to inflate and extract.
- */
-static int work_tree_matches(const char *name, const unsigned char *sha1)
-{
-       struct cache_entry *ce;
-       struct stat st;
-       int pos, len;
-
-       /* We do not read the cache ourselves here, because the
-        * benchmark with my previous version that always reads cache
-        * shows that it makes things worse for diff-tree comparing
-        * two linux-2.6 kernel trees in an already checked out work
-        * tree.  This is because most diff-tree comparisons deal with
-        * only a small number of files, while reading the cache is
-        * expensive for a large project, and its cost outweighs the
-        * savings we get by not inflating the object to a temporary
-        * file.  Practically, this code only helps when we are used
-        * by diff-cache --cached, which does read the cache before
-        * calling us.
-        */
-       if (!active_cache)
-               return 0;
-
-       len = strlen(name);
-       pos = cache_name_pos(name, len);
-       if (pos < 0)
-               return 0;
-       ce = active_cache[pos];
-       if ((lstat(name, &st) < 0) ||
-           !S_ISREG(st.st_mode) || /* careful! */
-           ce_match_stat(ce, &st, 0) ||
-           memcmp(sha1, ce->sha1, 20))
-               return 0;
-       /* we return 1 only when we can stat, it is a regular file,
-        * stat information matches, and sha1 recorded in the cache
-        * matches.  I.e. we know the file in the work tree really is
-        * the same as the <name, sha1> pair.
-        */
-       return 1;
-}
-
-static struct sha1_size_cache {
-       unsigned char sha1[20];
-       unsigned long size;
-} **sha1_size_cache;
-static int sha1_size_cache_nr, sha1_size_cache_alloc;
-
-static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
-                                                int find_only,
-                                                unsigned long size)
-{
-       int first, last;
-       struct sha1_size_cache *e;
-
-       first = 0;
-       last = sha1_size_cache_nr;
-       while (last > first) {
-               int cmp, next = (last + first) >> 1;
-               e = sha1_size_cache[next];
-               cmp = memcmp(e->sha1, sha1, 20);
-               if (!cmp)
-                       return e;
-               if (cmp < 0) {
-                       last = next;
-                       continue;
-               }
-               first = next+1;
-       }
-       /* not found */
-       if (find_only)
-               return NULL;
-       /* insert to make it at "first" */
-       if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
-               sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
-               sha1_size_cache = xrealloc(sha1_size_cache,
-                                          sha1_size_cache_alloc *
-                                          sizeof(*sha1_size_cache));
-       }
-       sha1_size_cache_nr++;
-       if (first < sha1_size_cache_nr)
-               memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
-                       (sha1_size_cache_nr - first - 1) *
-                       sizeof(*sha1_size_cache));
-       e = xmalloc(sizeof(struct sha1_size_cache));
-       sha1_size_cache[first] = e;
-       memcpy(e->sha1, sha1, 20);
-       e->size = size;
-       return e;
-}
-
-/*
- * While doing rename detection and pickaxe operation, we may need to
- * grab the data for the blob (or file) for our own in-core comparison.
- * diff_filespec has data and size fields for this purpose.
- */
-int diff_populate_filespec(struct diff_filespec *s, int size_only)
-{
-       int err = 0;
-       if (!DIFF_FILE_VALID(s))
-               die("internal error: asking to populate invalid file.");
-       if (S_ISDIR(s->mode))
-               return -1;
-
-       if (!use_size_cache)
-               size_only = 0;
-
-       if (s->data)
-               return err;
-       if (!s->sha1_valid ||
-           work_tree_matches(s->path, s->sha1)) {
-               struct stat st;
-               int fd;
-               if (lstat(s->path, &st) < 0) {
-                       if (errno == ENOENT) {
-                       err_empty:
-                               err = -1;
-                       empty:
-                               s->data = "";
-                               s->size = 0;
-                               return err;
-                       }
-               }
-               s->size = st.st_size;
-               if (!s->size)
-                       goto empty;
-               if (size_only)
-                       return 0;
-               if (S_ISLNK(st.st_mode)) {
-                       int ret;
-                       s->data = xmalloc(s->size);
-                       s->should_free = 1;
-                       ret = readlink(s->path, s->data, s->size);
-                       if (ret < 0) {
-                               free(s->data);
-                               goto err_empty;
-                       }
-                       return 0;
-               }
-               fd = open(s->path, O_RDONLY);
-               if (fd < 0)
-                       goto err_empty;
-               s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
-               close(fd);
-               if (s->data == MAP_FAILED)
-                       goto err_empty;
-               s->should_munmap = 1;
-       }
-       else {
-               char type[20];
-               struct sha1_size_cache *e;
-
-               if (size_only) {
-                       e = locate_size_cache(s->sha1, 1, 0);
-                       if (e) {
-                               s->size = e->size;
-                               return 0;
-                       }
-                       if (!sha1_object_info(s->sha1, type, &s->size))
-                               locate_size_cache(s->sha1, 0, s->size);
-               }
-               else {
-                       s->data = read_sha1_file(s->sha1, type, &s->size);
-                       s->should_free = 1;
-               }
-       }
-       return 0;
-}
-
-void diff_free_filespec_data(struct diff_filespec *s)
-{
-       if (s->should_free)
-               free(s->data);
-       else if (s->should_munmap)
-               munmap(s->data, s->size);
-       s->should_free = s->should_munmap = 0;
-       s->data = NULL;
-       free(s->cnt_data);
-       s->cnt_data = NULL;
-}
-
-static void prep_temp_blob(struct diff_tempfile *temp,
-                          void *blob,
-                          unsigned long size,
-                          const unsigned char *sha1,
-                          int mode)
-{
-       int fd;
-
-       fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
-       if (fd < 0)
-               die("unable to create temp-file");
-       if (write(fd, blob, size) != size)
-               die("unable to write temp-file");
-       close(fd);
-       temp->name = temp->tmp_path;
-       strcpy(temp->hex, sha1_to_hex(sha1));
-       temp->hex[40] = 0;
-       sprintf(temp->mode, "%06o", mode);
-}
-
-static void prepare_temp_file(const char *name,
-                             struct diff_tempfile *temp,
-                             struct diff_filespec *one)
-{
-       if (!DIFF_FILE_VALID(one)) {
-       not_a_valid_file:
-               /* A '-' entry produces this for file-2, and
-                * a '+' entry produces this for file-1.
-                */
-               temp->name = "/dev/null";
-               strcpy(temp->hex, ".");
-               strcpy(temp->mode, ".");
-               return;
-       }
-
-       if (!one->sha1_valid ||
-           work_tree_matches(name, one->sha1)) {
-               struct stat st;
-               if (lstat(name, &st) < 0) {
-                       if (errno == ENOENT)
-                               goto not_a_valid_file;
-                       die("stat(%s): %s", name, strerror(errno));
-               }
-               if (S_ISLNK(st.st_mode)) {
-                       int ret;
-                       char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
-                       if (sizeof(buf) <= st.st_size)
-                               die("symlink too long: %s", name);
-                       ret = readlink(name, buf, st.st_size);
-                       if (ret < 0)
-                               die("readlink(%s)", name);
-                       prep_temp_blob(temp, buf, st.st_size,
-                                      (one->sha1_valid ?
-                                       one->sha1 : null_sha1),
-                                      (one->sha1_valid ?
-                                       one->mode : S_IFLNK));
-               }
-               else {
-                       /* we can borrow from the file in the work tree */
-                       temp->name = name;
-                       if (!one->sha1_valid)
-                               strcpy(temp->hex, sha1_to_hex(null_sha1));
-                       else
-                               strcpy(temp->hex, sha1_to_hex(one->sha1));
-                       /* Even though we may sometimes borrow the
-                        * contents from the work tree, we always want
-                        * one->mode.  mode is trustworthy even when
-                        * !(one->sha1_valid), as long as
-                        * DIFF_FILE_VALID(one).
-                        */
-                       sprintf(temp->mode, "%06o", one->mode);
-               }
-               return;
-       }
-       else {
-               if (diff_populate_filespec(one, 0))
-                       die("cannot read data blob for %s", one->path);
-               prep_temp_blob(temp, one->data, one->size,
-                              one->sha1, one->mode);
-       }
-}
-
-static void remove_tempfile(void)
-{
-       int i;
-
-       for (i = 0; i < 2; i++)
-               if (diff_temp[i].name == diff_temp[i].tmp_path) {
-                       unlink(diff_temp[i].name);
-                       diff_temp[i].name = NULL;
-               }
-}
-
-static void remove_tempfile_on_signal(int signo)
-{
-       remove_tempfile();
-       signal(SIGINT, SIG_DFL);
-       raise(signo);
-}
-
-static int spawn_prog(const char *pgm, const char **arg)
-{
-       pid_t pid;
-       int status;
-
-       fflush(NULL);
-       pid = fork();
-       if (pid < 0)
-               die("unable to fork");
-       if (!pid) {
-               execvp(pgm, (char *const*) arg);
-               exit(255);
-       }
-
-       while (waitpid(pid, &status, 0) < 0) {
-               if (errno == EINTR)
-                       continue;
-               return -1;
-       }
-
-       /* Earlier we did not check the exit status because
-        * diff exits non-zero if files are different, and
-        * we are not interested in knowing that.  It was a
-        * mistake which made it harder to quit a diff-*
-        * session that uses the git-apply-patch-script as
-        * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
-        * should also exit non-zero only when it wants to
-        * abort the entire diff-* session.
-        */
-       if (WIFEXITED(status) && !WEXITSTATUS(status))
-               return 0;
-       return -1;
-}
-
-/* An external diff command takes:
- *
- * diff-cmd name infile1 infile1-sha1 infile1-mode \
- *               infile2 infile2-sha1 infile2-mode [ rename-to ]
- *
- */
-static void run_external_diff(const char *pgm,
-                             const char *name,
-                             const char *other,
-                             struct diff_filespec *one,
-                             struct diff_filespec *two,
-                             const char *xfrm_msg,
-                             int complete_rewrite)
-{
-       const char *spawn_arg[10];
-       struct diff_tempfile *temp = diff_temp;
-       int retval;
-       static int atexit_asked = 0;
-       const char *othername;
-       const char **arg = &spawn_arg[0];
-
-       othername = (other? other : name);
-       if (one && two) {
-               prepare_temp_file(name, &temp[0], one);
-               prepare_temp_file(othername, &temp[1], two);
-               if (! atexit_asked &&
-                   (temp[0].name == temp[0].tmp_path ||
-                    temp[1].name == temp[1].tmp_path)) {
-                       atexit_asked = 1;
-                       atexit(remove_tempfile);
-               }
-               signal(SIGINT, remove_tempfile_on_signal);
-       }
-
-       if (one && two) {
-               *arg++ = pgm;
-               *arg++ = name;
-               *arg++ = temp[0].name;
-               *arg++ = temp[0].hex;
-               *arg++ = temp[0].mode;
-               *arg++ = temp[1].name;
-               *arg++ = temp[1].hex;
-               *arg++ = temp[1].mode;
-               if (other) {
-                       *arg++ = other;
-                       *arg++ = xfrm_msg;
-               }
-       } else {
-               *arg++ = pgm;
-               *arg++ = name;
-       }
-       *arg = NULL;
-       retval = spawn_prog(pgm, spawn_arg);
-       remove_tempfile();
-       if (retval) {
-               fprintf(stderr, "external diff died, stopping at %s.\n", name);
-               exit(1);
-       }
-}
-
-static void run_diff_cmd(const char *pgm,
-                        const char *name,
-                        const char *other,
-                        struct diff_filespec *one,
-                        struct diff_filespec *two,
-                        const char *xfrm_msg,
-                        int complete_rewrite)
-{
-       if (pgm) {
-               run_external_diff(pgm, name, other, one, two, xfrm_msg,
-                                 complete_rewrite);
-               return;
-       }
-       if (one && two)
-               builtin_diff(name, other ? other : name,
-                            one, two, xfrm_msg, complete_rewrite);
-       else
-               printf("* Unmerged path %s\n", name);
-}
-
-static void diff_fill_sha1_info(struct diff_filespec *one)
-{
-       if (DIFF_FILE_VALID(one)) {
-               if (!one->sha1_valid) {
-                       struct stat st;
-                       if (lstat(one->path, &st) < 0)
-                               die("stat %s", one->path);
-                       if (index_path(one->sha1, one->path, &st, 0))
-                               die("cannot hash %s\n", one->path);
-               }
-       }
-       else
-               memset(one->sha1, 0, 20);
-}
-
-static void run_diff(struct diff_filepair *p, struct diff_options *o)
-{
-       const char *pgm = external_diff();
-       char msg[PATH_MAX*2+300], *xfrm_msg;
-       struct diff_filespec *one;
-       struct diff_filespec *two;
-       const char *name;
-       const char *other;
-       char *name_munged, *other_munged;
-       int complete_rewrite = 0;
-       int len;
-
-       if (DIFF_PAIR_UNMERGED(p)) {
-               /* unmerged */
-               run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, 0);
-               return;
-       }
-
-       name = p->one->path;
-       other = (strcmp(name, p->two->path) ? p->two->path : NULL);
-       name_munged = quote_one(name);
-       other_munged = quote_one(other);
-       one = p->one; two = p->two;
-
-       diff_fill_sha1_info(one);
-       diff_fill_sha1_info(two);
-
-       len = 0;
-       switch (p->status) {
-       case DIFF_STATUS_COPIED:
-               len += snprintf(msg + len, sizeof(msg) - len,
-                               "similarity index %d%%\n"
-                               "copy from %s\n"
-                               "copy to %s\n",
-                               (int)(0.5 + p->score * 100.0/MAX_SCORE),
-                               name_munged, other_munged);
-               break;
-       case DIFF_STATUS_RENAMED:
-               len += snprintf(msg + len, sizeof(msg) - len,
-                               "similarity index %d%%\n"
-                               "rename from %s\n"
-                               "rename to %s\n",
-                               (int)(0.5 + p->score * 100.0/MAX_SCORE),
-                               name_munged, other_munged);
-               break;
-       case DIFF_STATUS_MODIFIED:
-               if (p->score) {
-                       len += snprintf(msg + len, sizeof(msg) - len,
-                                       "dissimilarity index %d%%\n",
-                                       (int)(0.5 + p->score *
-                                             100.0/MAX_SCORE));
-                       complete_rewrite = 1;
-                       break;
-               }
-               /* fallthru */
-       default:
-               /* nothing */
-               ;
-       }
-
-       if (memcmp(one->sha1, two->sha1, 20)) {
-               char one_sha1[41];
-               int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
-               memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
-
-               len += snprintf(msg + len, sizeof(msg) - len,
-                               "index %.*s..%.*s",
-                               abbrev, one_sha1, abbrev,
-                               sha1_to_hex(two->sha1));
-               if (one->mode == two->mode)
-                       len += snprintf(msg + len, sizeof(msg) - len,
-                                       " %06o", one->mode);
-               len += snprintf(msg + len, sizeof(msg) - len, "\n");
-       }
-
-       if (len)
-               msg[--len] = 0;
-       xfrm_msg = len ? msg : NULL;
-
-       if (!pgm &&
-           DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
-           (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
-               /* a filepair that changes between file and symlink
-                * needs to be split into deletion and creation.
-                */
-               struct diff_filespec *null = alloc_filespec(two->path);
-               run_diff_cmd(NULL, name, other, one, null, xfrm_msg, 0);
-               free(null);
-               null = alloc_filespec(one->path);
-               run_diff_cmd(NULL, name, other, null, two, xfrm_msg, 0);
-               free(null);
-       }
-       else
-               run_diff_cmd(pgm, name, other, one, two, xfrm_msg,
-                            complete_rewrite);
-
-       free(name_munged);
-       free(other_munged);
-}
-
-static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
-               struct diffstat_t *diffstat)
-{
-       const char *name;
-       const char *other;
-
-       if (DIFF_PAIR_UNMERGED(p)) {
-               /* unmerged */
-               builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat);
-               return;
-       }
-
-       name = p->one->path;
-       other = (strcmp(name, p->two->path) ? p->two->path : NULL);
-
-       diff_fill_sha1_info(p->one);
-       diff_fill_sha1_info(p->two);
-
-       builtin_diffstat(name, other, p->one, p->two, diffstat);
-}
-
-void diff_setup(struct diff_options *options)
-{
-       memset(options, 0, sizeof(*options));
-       options->output_format = DIFF_FORMAT_RAW;
-       options->line_termination = '\n';
-       options->break_opt = -1;
-       options->rename_limit = -1;
-
-       options->change = diff_change;
-       options->add_remove = diff_addremove;
-}
-
-int diff_setup_done(struct diff_options *options)
-{
-       if ((options->find_copies_harder &&
-            options->detect_rename != DIFF_DETECT_COPY) ||
-           (0 <= options->rename_limit && !options->detect_rename))
-               return -1;
-
-       /*
-        * These cases always need recursive; we do not drop caller-supplied
-        * recursive bits for other formats here.
-        */
-       if ((options->output_format == DIFF_FORMAT_PATCH) ||
-           (options->output_format == DIFF_FORMAT_DIFFSTAT))
-               options->recursive = 1;
-
-       if (options->detect_rename && options->rename_limit < 0)
-               options->rename_limit = diff_rename_limit_default;
-       if (options->setup & DIFF_SETUP_USE_CACHE) {
-               if (!active_cache)
-                       /* read-cache does not die even when it fails
-                        * so it is safe for us to do this here.  Also
-                        * it does not smudge active_cache or active_nr
-                        * when it fails, so we do not have to worry about
-                        * cleaning it up ourselves either.
-                        */
-                       read_cache();
-       }
-       if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
-               use_size_cache = 1;
-       if (options->abbrev <= 0 || 40 < options->abbrev)
-               options->abbrev = 40; /* full */
-
-       return 0;
-}
-
-int diff_opt_parse(struct diff_options *options, const char **av, int ac)
-{
-       const char *arg = av[0];
-       if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
-               options->output_format = DIFF_FORMAT_PATCH;
-       else if (!strcmp(arg, "--patch-with-raw")) {
-               options->output_format = DIFF_FORMAT_PATCH;
-               options->with_raw = 1;
-       }
-       else if (!strcmp(arg, "--stat"))
-               options->output_format = DIFF_FORMAT_DIFFSTAT;
-       else if (!strcmp(arg, "--patch-with-stat")) {
-               options->output_format = DIFF_FORMAT_PATCH;
-               options->with_stat = 1;
-       }
-       else if (!strcmp(arg, "-z"))
-               options->line_termination = 0;
-       else if (!strncmp(arg, "-l", 2))
-               options->rename_limit = strtoul(arg+2, NULL, 10);
-       else if (!strcmp(arg, "--full-index"))
-               options->full_index = 1;
-       else if (!strcmp(arg, "--name-only"))
-               options->output_format = DIFF_FORMAT_NAME;
-       else if (!strcmp(arg, "--name-status"))
-               options->output_format = DIFF_FORMAT_NAME_STATUS;
-       else if (!strcmp(arg, "-R"))
-               options->reverse_diff = 1;
-       else if (!strncmp(arg, "-S", 2))
-               options->pickaxe = arg + 2;
-       else if (!strcmp(arg, "-s"))
-               options->output_format = DIFF_FORMAT_NO_OUTPUT;
-       else if (!strncmp(arg, "-O", 2))
-               options->orderfile = arg + 2;
-       else if (!strncmp(arg, "--diff-filter=", 14))
-               options->filter = arg + 14;
-       else if (!strcmp(arg, "--pickaxe-all"))
-               options->pickaxe_opts = DIFF_PICKAXE_ALL;
-       else if (!strcmp(arg, "--pickaxe-regex"))
-               options->pickaxe_opts = DIFF_PICKAXE_REGEX;
-       else if (!strncmp(arg, "-B", 2)) {
-               if ((options->break_opt =
-                    diff_scoreopt_parse(arg)) == -1)
-                       return -1;
-       }
-       else if (!strncmp(arg, "-M", 2)) {
-               if ((options->rename_score =
-                    diff_scoreopt_parse(arg)) == -1)
-                       return -1;
-               options->detect_rename = DIFF_DETECT_RENAME;
-       }
-       else if (!strncmp(arg, "-C", 2)) {
-               if ((options->rename_score =
-                    diff_scoreopt_parse(arg)) == -1)
-                       return -1;
-               options->detect_rename = DIFF_DETECT_COPY;
-       }
-       else if (!strcmp(arg, "--find-copies-harder"))
-               options->find_copies_harder = 1;
-       else if (!strcmp(arg, "--abbrev"))
-               options->abbrev = DEFAULT_ABBREV;
-       else if (!strncmp(arg, "--abbrev=", 9)) {
-               options->abbrev = strtoul(arg + 9, NULL, 10);
-               if (options->abbrev < MINIMUM_ABBREV)
-                       options->abbrev = MINIMUM_ABBREV;
-               else if (40 < options->abbrev)
-                       options->abbrev = 40;
-       }
-       else
-               return 0;
-       return 1;
-}
-
-static int parse_num(const char **cp_p)
-{
-       unsigned long num, scale;
-       int ch, dot;
-       const char *cp = *cp_p;
-
-       num = 0;
-       scale = 1;
-       dot = 0;
-       for(;;) {
-               ch = *cp;
-               if ( !dot && ch == '.' ) {
-                       scale = 1;
-                       dot = 1;
-               } else if ( ch == '%' ) {
-                       scale = dot ? scale*100 : 100;
-                       cp++;   /* % is always at the end */
-                       break;
-               } else if ( ch >= '0' && ch <= '9' ) {
-                       if ( scale < 100000 ) {
-                               scale *= 10;
-                               num = (num*10) + (ch-'0');
-                       }
-               } else {
-                       break;
-               }
-               cp++;
-       }
-       *cp_p = cp;
-
-       /* user says num divided by scale and we say internally that
-        * is MAX_SCORE * num / scale.
-        */
-       return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
-}
-
-int diff_scoreopt_parse(const char *opt)
-{
-       int opt1, opt2, cmd;
-
-       if (*opt++ != '-')
-               return -1;
-       cmd = *opt++;
-       if (cmd != 'M' && cmd != 'C' && cmd != 'B')
-               return -1; /* that is not a -M, -C nor -B option */
-
-       opt1 = parse_num(&opt);
-       if (cmd != 'B')
-               opt2 = 0;
-       else {
-               if (*opt == 0)
-                       opt2 = 0;
-               else if (*opt != '/')
-                       return -1; /* we expect -B80/99 or -B80 */
-               else {
-                       opt++;
-                       opt2 = parse_num(&opt);
-               }
-       }
-       if (*opt != 0)
-               return -1;
-       return opt1 | (opt2 << 16);
-}
-
-struct diff_queue_struct diff_queued_diff;
-
-void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
-{
-       if (queue->alloc <= queue->nr) {
-               queue->alloc = alloc_nr(queue->alloc);
-               queue->queue = xrealloc(queue->queue,
-                                       sizeof(dp) * queue->alloc);
-       }
-       queue->queue[queue->nr++] = dp;
-}
-
-struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
-                                struct diff_filespec *one,
-                                struct diff_filespec *two)
-{
-       struct diff_filepair *dp = xmalloc(sizeof(*dp));
-       dp->one = one;
-       dp->two = two;
-       dp->score = 0;
-       dp->status = 0;
-       dp->source_stays = 0;
-       dp->broken_pair = 0;
-       if (queue)
-               diff_q(queue, dp);
-       return dp;
-}
-
-void diff_free_filepair(struct diff_filepair *p)
-{
-       diff_free_filespec_data(p->one);
-       diff_free_filespec_data(p->two);
-       free(p->one);
-       free(p->two);
-       free(p);
-}
-
-/* This is different from find_unique_abbrev() in that
- * it stuffs the result with dots for alignment.
- */
-const char *diff_unique_abbrev(const unsigned char *sha1, int len)
-{
-       int abblen;
-       const char *abbrev;
-       if (len == 40)
-               return sha1_to_hex(sha1);
-
-       abbrev = find_unique_abbrev(sha1, len);
-       if (!abbrev)
-               return sha1_to_hex(sha1);
-       abblen = strlen(abbrev);
-       if (abblen < 37) {
-               static char hex[41];
-               if (len < abblen && abblen <= len + 2)
-                       sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
-               else
-                       sprintf(hex, "%s...", abbrev);
-               return hex;
-       }
-       return sha1_to_hex(sha1);
-}
-
-static void diff_flush_raw(struct diff_filepair *p,
-                          int line_termination,
-                          int inter_name_termination,
-                          struct diff_options *options,
-                          int output_format)
-{
-       int two_paths;
-       char status[10];
-       int abbrev = options->abbrev;
-       const char *path_one, *path_two;
-
-       path_one = p->one->path;
-       path_two = p->two->path;
-       if (line_termination) {
-               path_one = quote_one(path_one);
-               path_two = quote_one(path_two);
-       }
-
-       if (p->score)
-               sprintf(status, "%c%03d", p->status,
-                       (int)(0.5 + p->score * 100.0/MAX_SCORE));
-       else {
-               status[0] = p->status;
-               status[1] = 0;
-       }
-       switch (p->status) {
-       case DIFF_STATUS_COPIED:
-       case DIFF_STATUS_RENAMED:
-               two_paths = 1;
-               break;
-       case DIFF_STATUS_ADDED:
-       case DIFF_STATUS_DELETED:
-               two_paths = 0;
-               break;
-       default:
-               two_paths = 0;
-               break;
-       }
-       if (output_format != DIFF_FORMAT_NAME_STATUS) {
-               printf(":%06o %06o %s ",
-                      p->one->mode, p->two->mode,
-                      diff_unique_abbrev(p->one->sha1, abbrev));
-               printf("%s ",
-                      diff_unique_abbrev(p->two->sha1, abbrev));
-       }
-       printf("%s%c%s", status, inter_name_termination, path_one);
-       if (two_paths)
-               printf("%c%s", inter_name_termination, path_two);
-       putchar(line_termination);
-       if (path_one != p->one->path)
-               free((void*)path_one);
-       if (path_two != p->two->path)
-               free((void*)path_two);
-}
-
-static void diff_flush_name(struct diff_filepair *p,
-                           int inter_name_termination,
-                           int line_termination)
-{
-       char *path = p->two->path;
-
-       if (line_termination)
-               path = quote_one(p->two->path);
-       else
-               path = p->two->path;
-       printf("%s%c", path, line_termination);
-       if (p->two->path != path)
-               free(path);
-}
-
-int diff_unmodified_pair(struct diff_filepair *p)
-{
-       /* This function is written stricter than necessary to support
-        * the currently implemented transformers, but the idea is to
-        * let transformers to produce diff_filepairs any way they want,
-        * and filter and clean them up here before producing the output.
-        */
-       struct diff_filespec *one, *two;
-
-       if (DIFF_PAIR_UNMERGED(p))
-               return 0; /* unmerged is interesting */
-
-       one = p->one;
-       two = p->two;
-
-       /* deletion, addition, mode or type change
-        * and rename are all interesting.
-        */
-       if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
-           DIFF_PAIR_MODE_CHANGED(p) ||
-           strcmp(one->path, two->path))
-               return 0;
-
-       /* both are valid and point at the same path.  that is, we are
-        * dealing with a change.
-        */
-       if (one->sha1_valid && two->sha1_valid &&
-           !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
-               return 1; /* no change */
-       if (!one->sha1_valid && !two->sha1_valid)
-               return 1; /* both look at the same file on the filesystem. */
-       return 0;
-}
-
-static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
-{
-       if (diff_unmodified_pair(p))
-               return;
-
-       if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
-           (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
-               return; /* no tree diffs in patch format */
-
-       run_diff(p, o);
-}
-
-static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
-               struct diffstat_t *diffstat)
-{
-       if (diff_unmodified_pair(p))
-               return;
-
-       if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
-           (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
-               return; /* no tree diffs in patch format */
-
-       run_diffstat(p, o, diffstat);
-}
-
-int diff_queue_is_empty(void)
-{
-       struct diff_queue_struct *q = &diff_queued_diff;
-       int i;
-       for (i = 0; i < q->nr; i++)
-               if (!diff_unmodified_pair(q->queue[i]))
-                       return 0;
-       return 1;
-}
-
-#if DIFF_DEBUG
-void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
-{
-       fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
-               x, one ? one : "",
-               s->path,
-               DIFF_FILE_VALID(s) ? "valid" : "invalid",
-               s->mode,
-               s->sha1_valid ? sha1_to_hex(s->sha1) : "");
-       fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
-               x, one ? one : "",
-               s->size, s->xfrm_flags);
-}
-
-void diff_debug_filepair(const struct diff_filepair *p, int i)
-{
-       diff_debug_filespec(p->one, i, "one");
-       diff_debug_filespec(p->two, i, "two");
-       fprintf(stderr, "score %d, status %c stays %d broken %d\n",
-               p->score, p->status ? p->status : '?',
-               p->source_stays, p->broken_pair);
-}
-
-void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
-{
-       int i;
-       if (msg)
-               fprintf(stderr, "%s\n", msg);
-       fprintf(stderr, "q->nr = %d\n", q->nr);
-       for (i = 0; i < q->nr; i++) {
-               struct diff_filepair *p = q->queue[i];
-               diff_debug_filepair(p, i);
-       }
-}
-#endif
-
-static void diff_resolve_rename_copy(void)
-{
-       int i, j;
-       struct diff_filepair *p, *pp;
-       struct diff_queue_struct *q = &diff_queued_diff;
-
-       diff_debug_queue("resolve-rename-copy", q);
-
-       for (i = 0; i < q->nr; i++) {
-               p = q->queue[i];
-               p->status = 0; /* undecided */
-               if (DIFF_PAIR_UNMERGED(p))
-                       p->status = DIFF_STATUS_UNMERGED;
-               else if (!DIFF_FILE_VALID(p->one))
-                       p->status = DIFF_STATUS_ADDED;
-               else if (!DIFF_FILE_VALID(p->two))
-                       p->status = DIFF_STATUS_DELETED;
-               else if (DIFF_PAIR_TYPE_CHANGED(p))
-                       p->status = DIFF_STATUS_TYPE_CHANGED;
-
-               /* from this point on, we are dealing with a pair
-                * whose both sides are valid and of the same type, i.e.
-                * either in-place edit or rename/copy edit.
-                */
-               else if (DIFF_PAIR_RENAME(p)) {
-                       if (p->source_stays) {
-                               p->status = DIFF_STATUS_COPIED;
-                               continue;
-                       }
-                       /* See if there is some other filepair that
-                        * copies from the same source as us.  If so
-                        * we are a copy.  Otherwise we are either a
-                        * copy if the path stays, or a rename if it
-                        * does not, but we already handled "stays" case.
-                        */
-                       for (j = i + 1; j < q->nr; j++) {
-                               pp = q->queue[j];
-                               if (strcmp(pp->one->path, p->one->path))
-                                       continue; /* not us */
-                               if (!DIFF_PAIR_RENAME(pp))
-                                       continue; /* not a rename/copy */
-                               /* pp is a rename/copy from the same source */
-                               p->status = DIFF_STATUS_COPIED;
-                               break;
-                       }
-                       if (!p->status)
-                               p->status = DIFF_STATUS_RENAMED;
-               }
-               else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
-                        p->one->mode != p->two->mode)
-                       p->status = DIFF_STATUS_MODIFIED;
-               else {
-                       /* This is a "no-change" entry and should not
-                        * happen anymore, but prepare for broken callers.
-                        */
-                       error("feeding unmodified %s to diffcore",
-                             p->one->path);
-                       p->status = DIFF_STATUS_UNKNOWN;
-               }
-       }
-       diff_debug_queue("resolve-rename-copy done", q);
-}
-
-static void flush_one_pair(struct diff_filepair *p,
-                          int diff_output_format,
-                          struct diff_options *options,
-                          struct diffstat_t *diffstat)
-{
-       int inter_name_termination = '\t';
-       int line_termination = options->line_termination;
-       if (!line_termination)
-               inter_name_termination = 0;
-
-       switch (p->status) {
-       case DIFF_STATUS_UNKNOWN:
-               break;
-       case 0:
-               die("internal error in diff-resolve-rename-copy");
-               break;
-       default:
-               switch (diff_output_format) {
-               case DIFF_FORMAT_DIFFSTAT:
-                       diff_flush_stat(p, options, diffstat);
-                       break;
-               case DIFF_FORMAT_PATCH:
-                       diff_flush_patch(p, options);
-                       break;
-               case DIFF_FORMAT_RAW:
-               case DIFF_FORMAT_NAME_STATUS:
-                       diff_flush_raw(p, line_termination,
-                                      inter_name_termination,
-                                      options, diff_output_format);
-                       break;
-               case DIFF_FORMAT_NAME:
-                       diff_flush_name(p,
-                                       inter_name_termination,
-                                       line_termination);
-                       break;
-               case DIFF_FORMAT_NO_OUTPUT:
-                       break;
-               }
-       }
-}
-
-void diff_flush(struct diff_options *options)
-{
-       struct diff_queue_struct *q = &diff_queued_diff;
-       int i;
-       int diff_output_format = options->output_format;
-       struct diffstat_t *diffstat = NULL;
-
-       if (diff_output_format == DIFF_FORMAT_DIFFSTAT || options->with_stat) {
-               diffstat = xcalloc(sizeof (struct diffstat_t), 1);
-               diffstat->xm.consume = diffstat_consume;
-       }
-
-       if (options->with_raw) {
-               for (i = 0; i < q->nr; i++) {
-                       struct diff_filepair *p = q->queue[i];
-                       flush_one_pair(p, DIFF_FORMAT_RAW, options, NULL);
-               }
-               putchar(options->line_termination);
-       }
-       if (options->with_stat) {
-               for (i = 0; i < q->nr; i++) {
-                       struct diff_filepair *p = q->queue[i];
-                       flush_one_pair(p, DIFF_FORMAT_DIFFSTAT, options,
-                                       diffstat);
-               }
-               show_stats(diffstat);
-               free(diffstat);
-               diffstat = NULL;
-               putchar(options->line_termination);
-       }
-       for (i = 0; i < q->nr; i++) {
-               struct diff_filepair *p = q->queue[i];
-               flush_one_pair(p, diff_output_format, options, diffstat);
-               diff_free_filepair(p);
-       }
-
-       if (diffstat) {
-               show_stats(diffstat);
-               free(diffstat);
-       }
-
-       free(q->queue);
-       q->queue = NULL;
-       q->nr = q->alloc = 0;
-}
-
-static void diffcore_apply_filter(const char *filter)
-{
-       int i;
-       struct diff_queue_struct *q = &diff_queued_diff;
-       struct diff_queue_struct outq;
-       outq.queue = NULL;
-       outq.nr = outq.alloc = 0;
-
-       if (!filter)
-               return;
-
-       if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
-               int found;
-               for (i = found = 0; !found && i < q->nr; i++) {
-                       struct diff_filepair *p = q->queue[i];
-                       if (((p->status == DIFF_STATUS_MODIFIED) &&
-                            ((p->score &&
-                              strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
-                             (!p->score &&
-                              strchr(filter, DIFF_STATUS_MODIFIED)))) ||
-                           ((p->status != DIFF_STATUS_MODIFIED) &&
-                            strchr(filter, p->status)))
-                               found++;
-               }
-               if (found)
-                       return;
-
-               /* otherwise we will clear the whole queue
-                * by copying the empty outq at the end of this
-                * function, but first clear the current entries
-                * in the queue.
-                */
-               for (i = 0; i < q->nr; i++)
-                       diff_free_filepair(q->queue[i]);
-       }
-       else {
-               /* Only the matching ones */
-               for (i = 0; i < q->nr; i++) {
-                       struct diff_filepair *p = q->queue[i];
-
-                       if (((p->status == DIFF_STATUS_MODIFIED) &&
-                            ((p->score &&
-                              strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
-                             (!p->score &&
-                              strchr(filter, DIFF_STATUS_MODIFIED)))) ||
-                           ((p->status != DIFF_STATUS_MODIFIED) &&
-                            strchr(filter, p->status)))
-                               diff_q(&outq, p);
-                       else
-                               diff_free_filepair(p);
-               }
-       }
-       free(q->queue);
-       *q = outq;
-}
-
-void diffcore_std(struct diff_options *options)
-{
-       if (options->break_opt != -1)
-               diffcore_break(options->break_opt);
-       if (options->detect_rename)
-               diffcore_rename(options);
-       if (options->break_opt != -1)
-               diffcore_merge_broken();
-       if (options->pickaxe)
-               diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
-       if (options->orderfile)
-               diffcore_order(options->orderfile);
-       diff_resolve_rename_copy();
-       diffcore_apply_filter(options->filter);
-}
-
-
-void diffcore_std_no_resolve(struct diff_options *options)
-{
-       if (options->pickaxe)
-               diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
-       if (options->orderfile)
-               diffcore_order(options->orderfile);
-       diffcore_apply_filter(options->filter);
-}
-
-void diff_addremove(struct diff_options *options,
-                   int addremove, unsigned mode,
-                   const unsigned char *sha1,
-                   const char *base, const char *path)
-{
-       char concatpath[PATH_MAX];
-       struct diff_filespec *one, *two;
-
-       /* This may look odd, but it is a preparation for
-        * feeding "there are unchanged files which should
-        * not produce diffs, but when you are doing copy
-        * detection you would need them, so here they are"
-        * entries to the diff-core.  They will be prefixed
-        * with something like '=' or '*' (I haven't decided
-        * which but should not make any difference).
-        * Feeding the same new and old to diff_change() 
-        * also has the same effect.
-        * Before the final output happens, they are pruned after
-        * merged into rename/copy pairs as appropriate.
-        */
-       if (options->reverse_diff)
-               addremove = (addremove == '+' ? '-' :
-                            addremove == '-' ? '+' : addremove);
-
-       if (!path) path = "";
-       sprintf(concatpath, "%s%s", base, path);
-       one = alloc_filespec(concatpath);
-       two = alloc_filespec(concatpath);
-
-       if (addremove != '+')
-               fill_filespec(one, sha1, mode);
-       if (addremove != '-')
-               fill_filespec(two, sha1, mode);
-
-       diff_queue(&diff_queued_diff, one, two);
-}
-
-void diff_change(struct diff_options *options,
-                unsigned old_mode, unsigned new_mode,
-                const unsigned char *old_sha1,
-                const unsigned char *new_sha1,
-                const char *base, const char *path) 
-{
-       char concatpath[PATH_MAX];
-       struct diff_filespec *one, *two;
-
-       if (options->reverse_diff) {
-               unsigned tmp;
-               const unsigned char *tmp_c;
-               tmp = old_mode; old_mode = new_mode; new_mode = tmp;
-               tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
-       }
-       if (!path) path = "";
-       sprintf(concatpath, "%s%s", base, path);
-       one = alloc_filespec(concatpath);
-       two = alloc_filespec(concatpath);
-       fill_filespec(one, old_sha1, old_mode);
-       fill_filespec(two, new_sha1, new_mode);
-
-       diff_queue(&diff_queued_diff, one, two);
-}
-
-void diff_unmerge(struct diff_options *options,
-                 const char *path)
-{
-       struct diff_filespec *one, *two;
-       one = alloc_filespec(path);
-       two = alloc_filespec(path);
-       diff_queue(&diff_queued_diff, one, two);
-}