X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=blame.c;h=3ec1c8f1b287654cccb0f2427810d0afead5c44b;hb=67e78c3b8aeb44681b2d4ab2cf97145b7cc9a7a2;hp=dbce7e2c556ae11654418f1199ca41b369820f9a;hpb=c40610422e1157e71dbc3c1a2f9e19bbe117962f;p=git.git

diff --git a/blame.c b/blame.c
index dbce7e2c5..3ec1c8f1b 100644
--- a/blame.c
+++ b/blame.c
@@ -1,4 +1,11 @@
+/*
+ * Copyright (C) 2006, Fredrik Kuivinen <freku045@student.liu.se>
+ */
+
 #include <assert.h>
+#include <time.h>
+#include <sys/time.h>
+#include <math.h>
 
 #include "cache.h"
 #include "refs.h"
@@ -7,436 +14,1073 @@
 #include "tree.h"
 #include "blob.h"
 #include "diff.h"
+#include "diffcore.h"
+#include "revision.h"
+#include "xdiff-interface.h"
+#include "quote.h"
 
+#ifndef DEBUG
 #define DEBUG 0
-
-struct commit** blame_lines;
-int num_blame_lines;
-
-struct util_info
-{
-    int* line_map;
-    int num_lines;
-    unsigned char sha1[20]; /* blob sha, not commit! */
-    char* buf;
-    unsigned long size;
-//    const char* path;
+#endif
+
+static const char blame_usage[] =
+"git-blame [-c] [-l] [-t] [-f] [-n] [-p] [-S <revs-file>] [--] file [commit]\n"
+"  -c, --compatibility Use the same output mode as git-annotate (Default: off)\n"
+"  -l, --long          Show long commit SHA1 (Default: off)\n"
+"  -t, --time          Show raw timestamp (Default: off)\n"
+"  -f, --show-name     Show original filename (Default: auto)\n"
+"  -n, --show-number   Show original linenumber (Default: off)\n"
+"  -p, --porcelain     Show in a format designed for machine consumption\n"
+"  -S revs-file        Use revisions from revs-file instead of calling git-rev-list\n"
+"  -h, --help          This message";
+
+static struct commit **blame_lines;
+static int num_blame_lines;
+static char *blame_contents;
+static int blame_len;
+
+struct util_info {
+	int *line_map;
+	unsigned char sha1[20];	/* blob sha, not commit! */
+	char *buf;
+	unsigned long size;
+	int num_lines;
+	const char *pathname;
+	unsigned meta_given:1;
+
+	void *topo_data;
 };
 
-struct chunk
-{
-    int off1, len1; // ---
-    int off2, len2; // +++
+struct chunk {
+	int off1, len1;	/* --- */
+	int off2, len2;	/* +++ */
 };
 
-struct patch
-{
-    struct chunk* chunks;
-    int num;
+struct patch {
+	struct chunk *chunks;
+	int num;
 };
 
-static void get_blob(struct commit* commit);
+static void get_blob(struct commit *commit);
 
-int num_get_patch = 0;
-int num_commits = 0;
+/* Only used for statistics */
+static int num_get_patch;
+static int num_commits;
+static int patch_time;
+
+struct blame_diff_state {
+	struct xdiff_emit_state xm;
+	struct patch *ret;
+};
 
-struct patch* get_patch(struct commit* commit, struct commit* other)
+static void process_u0_diff(void *state_, char *line, unsigned long len)
 {
-    struct patch* ret = xmalloc(sizeof(struct patch));
-    ret->chunks = NULL;
-    ret->num = 0;
-
-    struct util_info* info_c = (struct util_info*) commit->object.util;
-    struct util_info* info_o = (struct util_info*) other->object.util;
-
-    if(!memcmp(info_c->sha1, info_o->sha1, 20))
-        return ret;
-
-    get_blob(commit);
-    get_blob(other);
-
-    FILE* fout = fopen("/tmp/git-blame-tmp1", "w");
-    if(!fout)
-        die("fopen tmp1 failed: %s", strerror(errno));
-
-    if(fwrite(info_c->buf, info_c->size, 1, fout) != 1)
-        die("fwrite 1 failed: %s", strerror(errno));
-    fclose(fout);
-
-    fout = fopen("/tmp/git-blame-tmp2", "w");
-    if(!fout)
-        die("fopen tmp2 failed: %s", strerror(errno));
-
-    if(fwrite(info_o->buf, info_o->size, 1, fout) != 1)
-        die("fwrite 2 failed: %s", strerror(errno));
-    fclose(fout);
-
-    FILE* fin = popen("diff -u0 /tmp/git-blame-tmp1 /tmp/git-blame-tmp2", "r");
-    if(!fin)
-        die("popen failed: %s", strerror(errno));
-
-    char buf[1024];
-    while(fgets(buf, sizeof(buf), fin)) {
-        if(buf[0] != '@' || buf[1] != '@')
-            continue;
-
-        if(DEBUG)
-            printf("chunk line: %s", buf);
-        ret->num++;
-        ret->chunks = xrealloc(ret->chunks, sizeof(struct chunk)*ret->num);
-        struct chunk* chunk = &ret->chunks[ret->num-1];
-
-        assert(!strncmp(buf, "@@ -", 4));
-
-        char* start = buf+4;
-        char* sp = index(start, ' ');
-        *sp = '\0';
-        if(index(start, ',')) {
-            int ret = sscanf(start, "%d,%d", &chunk->off1, &chunk->len1);
-            assert(ret == 2);
-        } else {
-            int ret = sscanf(start, "%d", &chunk->off1);
-            assert(ret == 1);
-            chunk->len1 = 1;
-        }
-        *sp = ' ';
-
-        start = sp+1;
-        sp = index(start, ' ');
-        *sp = '\0';
-        if(index(start, ',')) {
-            int ret = sscanf(start, "%d,%d", &chunk->off2, &chunk->len2);
-            assert(ret == 2);
-        } else {
-            int ret = sscanf(start, "%d", &chunk->off2);
-            assert(ret == 1);
-            chunk->len2 = 1;
-        }
-        *sp = ' ';
-
-        if(chunk->off1 > 0)
-            chunk->off1 -= 1;
-        if(chunk->off2 > 0)
-            chunk->off2 -= 1;
-
-        assert(chunk->off1 >= 0);
-        assert(chunk->off2 >= 0);
-    }
-    fclose(fin);
-
-    num_get_patch++;
-    return ret;
+	struct blame_diff_state *state = state_;
+	struct chunk *chunk;
+
+	if (len < 4 || line[0] != '@' || line[1] != '@')
+		return;
+
+	if (DEBUG)
+		printf("chunk line: %.*s", (int)len, line);
+	state->ret->num++;
+	state->ret->chunks = xrealloc(state->ret->chunks,
+				      sizeof(struct chunk) * state->ret->num);
+	chunk = &state->ret->chunks[state->ret->num - 1];
+
+	assert(!strncmp(line, "@@ -", 4));
+
+	if (parse_hunk_header(line, len,
+			      &chunk->off1, &chunk->len1,
+			      &chunk->off2, &chunk->len2)) {
+		state->ret->num--;
+		return;
+	}
+
+	if (chunk->len1 == 0)
+		chunk->off1++;
+	if (chunk->len2 == 0)
+		chunk->off2++;
+
+	if (chunk->off1 > 0)
+		chunk->off1--;
+	if (chunk->off2 > 0)
+		chunk->off2--;
+
+	assert(chunk->off1 >= 0);
+	assert(chunk->off2 >= 0);
 }
 
-void free_patch(struct patch* p)
+static struct patch *get_patch(struct commit *commit, struct commit *other)
 {
-    free(p->chunks);
-    free(p);
+	struct blame_diff_state state;
+	xpparam_t xpp;
+	xdemitconf_t xecfg;
+	mmfile_t file_c, file_o;
+	xdemitcb_t ecb;
+	struct util_info *info_c = (struct util_info *)commit->util;
+	struct util_info *info_o = (struct util_info *)other->util;
+	struct timeval tv_start, tv_end;
+
+	get_blob(commit);
+	file_c.ptr = info_c->buf;
+	file_c.size = info_c->size;
+
+	get_blob(other);
+	file_o.ptr = info_o->buf;
+	file_o.size = info_o->size;
+
+	gettimeofday(&tv_start, NULL);
+
+	xpp.flags = XDF_NEED_MINIMAL;
+	xecfg.ctxlen = 0;
+	xecfg.flags = 0;
+	ecb.outf = xdiff_outf;
+	ecb.priv = &state;
+	memset(&state, 0, sizeof(state));
+	state.xm.consume = process_u0_diff;
+	state.ret = xmalloc(sizeof(struct patch));
+	state.ret->chunks = NULL;
+	state.ret->num = 0;
+
+	xdl_diff(&file_c, &file_o, &xpp, &xecfg, &ecb);
+
+	gettimeofday(&tv_end, NULL);
+	patch_time += 1000000 * (tv_end.tv_sec - tv_start.tv_sec) +
+		tv_end.tv_usec - tv_start.tv_usec;
+
+	num_get_patch++;
+	return state.ret;
 }
 
-static int get_blob_sha1_internal(unsigned char *sha1, const char *base, int baselen,
-                                  const char *pathname, unsigned mode, int stage);
+static void free_patch(struct patch *p)
+{
+	free(p->chunks);
+	free(p);
+}
 
+static int get_blob_sha1_internal(const unsigned char *sha1, const char *base,
+				  int baselen, const char *pathname,
+				  unsigned mode, int stage);
 
 static unsigned char blob_sha1[20];
-static int get_blob_sha1(struct tree* t, const char* pathname, unsigned char* sha1)
+static const char *blame_file;
+static int get_blob_sha1(struct tree *t, const char *pathname,
+			 unsigned char *sha1)
 {
-    const char *pathspec[2];
-    pathspec[0] = pathname;
-    pathspec[1] = NULL;
-    memset(blob_sha1, 0, sizeof(blob_sha1));
-    read_tree_recursive(t, "", 0, 0, pathspec, get_blob_sha1_internal);
-
-    int i;
-    for(i = 0; i < 20; i++) {
-        if(blob_sha1[i] != 0)
-            break;
-    }
-
-    if(i == 20)
-        return -1;
-
-    memcpy(sha1, blob_sha1, 20);
-    return 0;
+	const char *pathspec[2];
+	blame_file = pathname;
+	pathspec[0] = pathname;
+	pathspec[1] = NULL;
+	hashclr(blob_sha1);
+	read_tree_recursive(t, "", 0, 0, pathspec, get_blob_sha1_internal);
+
+	if (is_null_sha1(blob_sha1))
+		return -1;
+
+	hashcpy(sha1, blob_sha1);
+	return 0;
 }
 
-static int get_blob_sha1_internal(unsigned char *sha1, const char *base, int baselen,
-                                  const char *pathname, unsigned mode, int stage)
+static int get_blob_sha1_internal(const unsigned char *sha1, const char *base,
+				  int baselen, const char *pathname,
+				  unsigned mode, int stage)
 {
-//    printf("Got blob: %s base: '%s' baselen: %d pathname: '%s' mode: %o stage: %d\n",
-//           sha1_to_hex(sha1), base, baselen, pathname, mode, stage);
+	if (S_ISDIR(mode))
+		return READ_TREE_RECURSIVE;
 
-    if(S_ISDIR(mode))
-        return READ_TREE_RECURSIVE;
+	if (strncmp(blame_file, base, baselen) ||
+	    strcmp(blame_file + baselen, pathname))
+		return -1;
 
-    memcpy(blob_sha1, sha1, 20);
-    return -1;
+	hashcpy(blob_sha1, sha1);
+	return -1;
 }
 
-static void get_blob(struct commit* commit)
+static void get_blob(struct commit *commit)
 {
-    struct util_info* info = commit->object.util;
-    char type[20];
+	struct util_info *info = commit->util;
+	char type[20];
 
-    if(info->buf)
-        return;
+	if (info->buf)
+		return;
 
-    info->buf = read_sha1_file(info->sha1, type, &info->size);
-    assert(!strcmp(type, "blob"));
+	info->buf = read_sha1_file(info->sha1, type, &info->size);
+
+	assert(!strcmp(type, blob_type));
 }
 
-void print_patch(struct patch* p)
+/* For debugging only */
+static void print_patch(struct patch *p)
 {
-    printf("Num chunks: %d\n", p->num);
-    int i;
-    for(i = 0; i < p->num; i++) {
-        printf("%d,%d %d,%d\n", p->chunks[i].off1, p->chunks[i].len1, p->chunks[i].off2, p->chunks[i].len2);
-    }
+	int i;
+	printf("Num chunks: %d\n", p->num);
+	for (i = 0; i < p->num; i++) {
+		printf("%d,%d %d,%d\n", p->chunks[i].off1, p->chunks[i].len1,
+		       p->chunks[i].off2, p->chunks[i].len2);
+	}
 }
 
-
-// p is a patch from commit to other.
-void fill_line_map(struct commit* commit, struct commit* other, struct patch* p)
+#if DEBUG
+/* For debugging only */
+static void print_map(struct commit *cmit, struct commit *other)
 {
-    int num_lines = ((struct util_info*) commit->object.util)->num_lines;
-    int* line_map = ((struct util_info*) commit->object.util)->line_map;
-    int num_lines2 = ((struct util_info*) other->object.util)->num_lines;
-    int* line_map2 = ((struct util_info*) other->object.util)->line_map;
-    int cur_chunk = 0;
-    int i1, i2;
-
-    if(p->num && DEBUG)
-        print_patch(p);
+	struct util_info *util = cmit->util;
+	struct util_info *util2 = other->util;
+
+	int i;
+	int max =
+	    util->num_lines >
+	    util2->num_lines ? util->num_lines : util2->num_lines;
+	int num;
+
+	if (print_map == NULL)
+		; /* to avoid "unused function" warning */
+
+	for (i = 0; i < max; i++) {
+		printf("i: %d ", i);
+		num = -1;
+
+		if (i < util->num_lines) {
+			num = util->line_map[i];
+			printf("%d\t", num);
+		}
+		else
+			printf("\t");
+
+		if (i < util2->num_lines) {
+			int num2 = util2->line_map[i];
+			printf("%d\t", num2);
+			if (num != -1 && num2 != num)
+				printf("---");
+		}
+		else
+			printf("\t");
+
+		printf("\n");
+	}
+}
+#endif
 
-    for(i1 = 0; i1 < num_lines; i1++)
-        line_map[i1] = -1;
+/* p is a patch from commit to other. */
+static void fill_line_map(struct commit *commit, struct commit *other,
+			  struct patch *p)
+{
+	struct util_info *util = commit->util;
+	struct util_info *util2 = other->util;
+	int *map = util->line_map;
+	int *map2 = util2->line_map;
+	int cur_chunk = 0;
+	int i1, i2;
+
+	if (DEBUG) {
+		if (p->num)
+			print_patch(p);
+		printf("num lines 1: %d num lines 2: %d\n", util->num_lines,
+		       util2->num_lines);
+	}
+
+	for (i1 = 0, i2 = 0; i1 < util->num_lines; i1++, i2++) {
+		struct chunk *chunk = NULL;
+		if (cur_chunk < p->num)
+			chunk = &p->chunks[cur_chunk];
+
+		if (chunk && chunk->off1 == i1) {
+			if (DEBUG && i2 != chunk->off2)
+				printf("i2: %d off2: %d\n", i2, chunk->off2);
+
+			assert(i2 == chunk->off2);
+
+			i1--;
+			i2--;
+			if (chunk->len1 > 0)
+				i1 += chunk->len1;
+
+			if (chunk->len2 > 0)
+				i2 += chunk->len2;
+
+			cur_chunk++;
+		}
+		else {
+			if (i2 >= util2->num_lines)
+				break;
+
+			if (map[i1] != map2[i2] && map[i1] != -1) {
+				if (DEBUG)
+					printf("map: i1: %d %d %p i2: %d %d %p\n",
+					       i1, map[i1],
+					       (void *) (i1 != -1 ? blame_lines[map[i1]] : NULL),
+					       i2, map2[i2],
+					       (void *) (i2 != -1 ? blame_lines[map2[i2]] : NULL));
+				if (map2[i2] != -1 &&
+				    blame_lines[map[i1]] &&
+				    !blame_lines[map2[i2]])
+					map[i1] = map2[i2];
+			}
+
+			if (map[i1] == -1 && map2[i2] != -1)
+				map[i1] = map2[i2];
+		}
+
+		if (DEBUG > 1)
+			printf("l1: %d l2: %d i1: %d i2: %d\n",
+			       map[i1], map2[i2], i1, i2);
+	}
+}
 
-    if(DEBUG)
-        printf("num lines 1: %d num lines 2: %d\n", num_lines, num_lines2);
+static int map_line(struct commit *commit, int line)
+{
+	struct util_info *info = commit->util;
+	assert(line >= 0 && line < info->num_lines);
+	return info->line_map[line];
+}
 
-    for(i1 = 0, i2 = 0; i1 < num_lines; i1++, i2++) {
-        if(DEBUG > 1)
-            printf("%d %d\n", i1, i2);
+static struct util_info *get_util(struct commit *commit)
+{
+	struct util_info *util = commit->util;
 
-        if(i2 >= num_lines2)
-            break;
+	if (util)
+		return util;
 
-        line_map[i1] = line_map2[i2];
+	util = xcalloc(1, sizeof(struct util_info));
+	util->num_lines = -1;
+	commit->util = util;
+	return util;
+}
 
-        struct chunk* chunk = NULL;
-        if(cur_chunk < p->num)
-            chunk = &p->chunks[cur_chunk];
+static int fill_util_info(struct commit *commit)
+{
+	struct util_info *util = commit->util;
 
-        if(chunk && chunk->off1 == i1) {
-            i2 = chunk->off2;
+	assert(util);
+	assert(util->pathname);
 
-            if(chunk->len1 > 0)
-                i1 += chunk->len1-1;
-            if(chunk->len2 > 0)
-                i2 += chunk->len2-1;
-            cur_chunk++;
-        }
-    }
+	return !!get_blob_sha1(commit->tree, util->pathname, util->sha1);
 }
 
-int map_line(struct commit* commit, int line)
+static void alloc_line_map(struct commit *commit)
 {
-    struct util_info* info = commit->object.util;
-    assert(line >= 0 && line < info->num_lines);
-    return info->line_map[line];
-}
+	struct util_info *util = commit->util;
+	int i;
 
-int fill_util_info(struct commit* commit, const char* path)
-{
-    if(commit->object.util)
-        return 0;
+	if (util->line_map)
+		return;
 
-    struct util_info* util = xmalloc(sizeof(struct util_info));
-    util->buf = NULL;
-    util->size = 0;
-    util->num_lines = -1;
-    util->line_map = NULL;
+	get_blob(commit);
 
-    commit->object.util = util;
+	util->num_lines = 0;
+	for (i = 0; i < util->size; i++) {
+		if (util->buf[i] == '\n')
+			util->num_lines++;
+	}
+	if (util->buf[util->size - 1] != '\n')
+		util->num_lines++;
 
-    if(get_blob_sha1(commit->tree, path, util->sha1))
-        return -1;
+	util->line_map = xmalloc(sizeof(int) * util->num_lines);
 
-    return 0;
+	for (i = 0; i < util->num_lines; i++)
+		util->line_map[i] = -1;
 }
 
-void alloc_line_map(struct commit* commit)
+static void init_first_commit(struct commit *commit, const char *filename)
 {
-    struct util_info* util = commit->object.util;
+	struct util_info *util = commit->util;
+	int i;
 
-    if(util->line_map)
-        return;
+	util->pathname = filename;
+	if (fill_util_info(commit))
+		die("fill_util_info failed");
 
-    get_blob(commit);
+	alloc_line_map(commit);
 
-    int i;
-    util->num_lines = 0;
-    for(i = 0; i < util->size; i++) {
-        if(util->buf[i] == '\n')
-            util->num_lines++;
-    }
-    util->line_map = xmalloc(sizeof(int)*util->num_lines);
+	util = commit->util;
+
+	for (i = 0; i < util->num_lines; i++)
+		util->line_map[i] = i;
 }
 
-void copy_line_map(struct commit* dst, struct commit* src)
+static void process_commits(struct rev_info *rev, const char *path,
+			    struct commit **initial)
 {
-    struct util_info* u_dst = dst->object.util;
-    struct util_info* u_src = src->object.util;
-
-    u_dst->line_map = u_src->line_map;
-    u_dst->num_lines = u_src->num_lines;
-    u_dst->buf = u_src->buf;
-    u_dst->size = u_src->size;
+	int i;
+	struct util_info *util;
+	int lines_left;
+	int *blame_p;
+	int *new_lines;
+	int new_lines_len;
+
+	struct commit *commit = get_revision(rev);
+	assert(commit);
+	init_first_commit(commit, path);
+
+	util = commit->util;
+	num_blame_lines = util->num_lines;
+	blame_lines = xmalloc(sizeof(struct commit *) * num_blame_lines);
+	blame_contents = util->buf;
+	blame_len = util->size;
+
+	for (i = 0; i < num_blame_lines; i++)
+		blame_lines[i] = NULL;
+
+	lines_left = num_blame_lines;
+	blame_p = xmalloc(sizeof(int) * num_blame_lines);
+	new_lines = xmalloc(sizeof(int) * num_blame_lines);
+	do {
+		struct commit_list *parents;
+		int num_parents;
+		struct util_info *util;
+
+		if (DEBUG)
+			printf("\nProcessing commit: %d %s\n", num_commits,
+			       sha1_to_hex(commit->object.sha1));
+
+		if (lines_left == 0)
+			return;
+
+		num_commits++;
+		memset(blame_p, 0, sizeof(int) * num_blame_lines);
+		new_lines_len = 0;
+		num_parents = 0;
+		for (parents = commit->parents;
+		     parents != NULL; parents = parents->next)
+			num_parents++;
+
+		if (num_parents == 0)
+			*initial = commit;
+
+		if (fill_util_info(commit))
+			continue;
+
+		alloc_line_map(commit);
+		util = commit->util;
+
+		for (parents = commit->parents;
+		     parents != NULL; parents = parents->next) {
+			struct commit *parent = parents->item;
+			struct patch *patch;
+
+			if (parse_commit(parent) < 0)
+				die("parse_commit error");
+
+			if (DEBUG)
+				printf("parent: %s\n",
+				       sha1_to_hex(parent->object.sha1));
+
+			if (fill_util_info(parent)) {
+				num_parents--;
+				continue;
+			}
+
+			patch = get_patch(parent, commit);
+                        alloc_line_map(parent);
+                        fill_line_map(parent, commit, patch);
+
+                        for (i = 0; i < patch->num; i++) {
+                            int l;
+                            for (l = 0; l < patch->chunks[i].len2; l++) {
+                                int mapped_line =
+                                    map_line(commit, patch->chunks[i].off2 + l);
+                                if (mapped_line != -1) {
+                                    blame_p[mapped_line]++;
+                                    if (blame_p[mapped_line] == num_parents)
+                                        new_lines[new_lines_len++] = mapped_line;
+                                }
+                            }
+			}
+                        free_patch(patch);
+		}
+
+		if (DEBUG)
+			printf("parents: %d\n", num_parents);
+
+		for (i = 0; i < new_lines_len; i++) {
+			int mapped_line = new_lines[i];
+			if (blame_lines[mapped_line] == NULL) {
+				blame_lines[mapped_line] = commit;
+				lines_left--;
+				if (DEBUG)
+					printf("blame: mapped: %d i: %d\n",
+					       mapped_line, i);
+			}
+		}
+	} while ((commit = get_revision(rev)) != NULL);
 }
 
-void process_commits(struct commit_list* list, const char* path)
+static int compare_tree_path(struct rev_info *revs,
+			     struct commit *c1, struct commit *c2)
 {
-    int i;
-
-    while(list) {
-        struct commit* commit = pop_commit(&list);
-        struct commit_list* parents;
-        struct util_info* info;
-
-        info = commit->object.util;
-        num_commits++;
-        if(DEBUG)
-            printf("\nProcessing commit: %d %s\n", num_commits, sha1_to_hex(commit->object.sha1));
-        for(parents = commit->parents;
-            parents != NULL; parents = parents->next) {
-            struct commit* parent = parents->item;
-
-            if(parse_commit(parent) < 0)
-                die("parse_commit error");
-
-            if(DEBUG)
-                printf("parent: %s\n", sha1_to_hex(parent->object.sha1));
-
-            if(fill_util_info(parent, path))
-                continue;
-
-            // Temporarily assign everything to the parent.
-            int num_blame = 0;
-            for(i = 0; i < num_blame_lines; i++) {
-                if(blame_lines[i] == commit) {
-                    num_blame++;
-                    blame_lines[i] = parent;
-                }
-            }
-
-            if(num_blame == 0)
-                continue;
-
-            struct patch* patch = get_patch(parent, commit);
-            if(patch->num == 0) {
-                copy_line_map(parent, commit);
-            } else {
-                alloc_line_map(parent);
-                fill_line_map(parent, commit, patch);
-            }
-
-            for(i = 0; i < patch->num; i++) {
-                int l;
-                for(l = 0; l < patch->chunks[i].len2; l++) {
-                    int mapped_line = map_line(commit, patch->chunks[i].off2 + l);
-                    if(mapped_line != -1 && blame_lines[mapped_line] == parent)
-                        blame_lines[mapped_line] = commit;
-                }
-            }
-            free_patch(patch);
-        }
-    }
+	int ret;
+	const char *paths[2];
+	struct util_info *util = c2->util;
+	paths[0] = util->pathname;
+	paths[1] = NULL;
+
+	diff_tree_setup_paths(get_pathspec(revs->prefix, paths),
+			      &revs->pruning);
+	ret = rev_compare_tree(revs, c1->tree, c2->tree);
+	diff_tree_release_paths(&revs->pruning);
+	return ret;
 }
 
-#define SEEN 1
-struct commit_list* get_commit_list(struct commit* commit, const char* pathname)
+static int same_tree_as_empty_path(struct rev_info *revs, struct tree *t1,
+				   const char *path)
 {
-    struct commit_list* ret = NULL;
-    struct commit_list* process = NULL;
-    unsigned char sha1[20];
-
-    commit_list_insert(commit, &process);
-
-    while(process) {
-        struct commit* com = pop_commit(&process);
-        if(com->object.flags & SEEN)
-            continue;
-
-        com->object.flags |= SEEN;
-        commit_list_insert(com, &ret);
-        struct commit_list* parents;
-
-        parse_commit(com);
-
-        for(parents = com->parents;
-            parents != NULL; parents = parents->next) {
-            struct commit* parent = parents->item;
-
-            parse_commit(parent);
-
-            if(!get_blob_sha1(parent->tree, pathname, sha1))
-                commit_list_insert(parent, &process);
-        }
-    }
-
-    return ret;
+	int ret;
+	const char *paths[2];
+	paths[0] = path;
+	paths[1] = NULL;
+
+	diff_tree_setup_paths(get_pathspec(revs->prefix, paths),
+			      &revs->pruning);
+	ret = rev_same_tree_as_empty(revs, t1);
+	diff_tree_release_paths(&revs->pruning);
+	return ret;
 }
 
-int main(int argc, const char **argv)
+static const char *find_rename(struct commit *commit, struct commit *parent)
 {
-    unsigned char sha1[20];
-    struct commit *commit;
-    const char* filename;
-    int i;
-
-    setup_git_directory();
+	struct util_info *cutil = commit->util;
+	struct diff_options diff_opts;
+	const char *paths[1];
+	int i;
+
+	if (DEBUG) {
+		printf("find_rename commit: %s ",
+		       sha1_to_hex(commit->object.sha1));
+		puts(sha1_to_hex(parent->object.sha1));
+	}
+
+	diff_setup(&diff_opts);
+	diff_opts.recursive = 1;
+	diff_opts.detect_rename = DIFF_DETECT_RENAME;
+	paths[0] = NULL;
+	diff_tree_setup_paths(paths, &diff_opts);
+	if (diff_setup_done(&diff_opts) < 0)
+		die("diff_setup_done failed");
+
+	diff_tree_sha1(commit->tree->object.sha1, parent->tree->object.sha1,
+		       "", &diff_opts);
+	diffcore_std(&diff_opts);
+
+	for (i = 0; i < diff_queued_diff.nr; i++) {
+		struct diff_filepair *p = diff_queued_diff.queue[i];
+
+		if (p->status == 'R' &&
+		    !strcmp(p->one->path, cutil->pathname)) {
+			if (DEBUG)
+				printf("rename %s -> %s\n",
+				       p->one->path, p->two->path);
+			return p->two->path;
+		}
+	}
+
+	return 0;
+}
 
-    if (argc != 3)
-        die("Usage: blame commit-ish file");
+static void simplify_commit(struct rev_info *revs, struct commit *commit)
+{
+	struct commit_list **pp, *parent;
+
+	if (!commit->tree)
+		return;
+
+	if (!commit->parents) {
+		struct util_info *util = commit->util;
+		if (!same_tree_as_empty_path(revs, commit->tree,
+					     util->pathname))
+			commit->object.flags |= TREECHANGE;
+		return;
+	}
+
+	pp = &commit->parents;
+	while ((parent = *pp) != NULL) {
+		struct commit *p = parent->item;
+
+		if (p->object.flags & UNINTERESTING) {
+			pp = &parent->next;
+			continue;
+		}
+
+		parse_commit(p);
+		switch (compare_tree_path(revs, p, commit)) {
+		case REV_TREE_SAME:
+			parent->next = NULL;
+			commit->parents = parent;
+			get_util(p)->pathname = get_util(commit)->pathname;
+			return;
+
+		case REV_TREE_NEW:
+		{
+			struct util_info *util = commit->util;
+			if (revs->remove_empty_trees &&
+			    same_tree_as_empty_path(revs, p->tree,
+						    util->pathname)) {
+				const char *new_name = find_rename(commit, p);
+				if (new_name) {
+					struct util_info *putil = get_util(p);
+					if (!putil->pathname)
+						putil->pathname = xstrdup(new_name);
+				}
+				else {
+					*pp = parent->next;
+					continue;
+				}
+			}
+		}
+
+		/* fallthrough */
+		case REV_TREE_DIFFERENT:
+			pp = &parent->next;
+			if (!get_util(p)->pathname)
+				get_util(p)->pathname =
+					get_util(commit)->pathname;
+			continue;
+		}
+		die("bad tree compare for commit %s",
+		    sha1_to_hex(commit->object.sha1));
+	}
+	commit->object.flags |= TREECHANGE;
+}
 
-    if (get_sha1(argv[1], sha1))
-        die("get_sha1 failed");
+struct commit_info
+{
+	char *author;
+	char *author_mail;
+	unsigned long author_time;
+	char *author_tz;
+
+	/* filled only when asked for details */
+	char *committer;
+	char *committer_mail;
+	unsigned long committer_time;
+	char *committer_tz;
+
+	char *summary;
+};
 
-    commit = lookup_commit_reference(sha1);
+static void get_ac_line(const char *inbuf, const char *what,
+			int bufsz, char *person, char **mail,
+			unsigned long *time, char **tz)
+{
+	int len;
+	char *tmp, *endp;
+
+	tmp = strstr(inbuf, what);
+	if (!tmp)
+		goto error_out;
+	tmp += strlen(what);
+	endp = strchr(tmp, '\n');
+	if (!endp)
+		len = strlen(tmp);
+	else
+		len = endp - tmp;
+	if (bufsz <= len) {
+	error_out:
+		/* Ugh */
+		person = *mail = *tz = "(unknown)";
+		*time = 0;
+		return;
+	}
+	memcpy(person, tmp, len);
+
+	tmp = person;
+	tmp += len;
+	*tmp = 0;
+	while (*tmp != ' ')
+		tmp--;
+	*tz = tmp+1;
+
+	*tmp = 0;
+	while (*tmp != ' ')
+		tmp--;
+	*time = strtoul(tmp, NULL, 10);
+
+	*tmp = 0;
+	while (*tmp != ' ')
+		tmp--;
+	*mail = tmp + 1;
+	*tmp = 0;
+}
 
-    filename = argv[2];
+static void get_commit_info(struct commit *commit, struct commit_info *ret, int detailed)
+{
+	int len;
+	char *tmp, *endp;
+	static char author_buf[1024];
+	static char committer_buf[1024];
+	static char summary_buf[1024];
+
+	ret->author = author_buf;
+	get_ac_line(commit->buffer, "\nauthor ",
+		    sizeof(author_buf), author_buf, &ret->author_mail,
+		    &ret->author_time, &ret->author_tz);
+
+	if (!detailed)
+		return;
+
+	ret->committer = committer_buf;
+	get_ac_line(commit->buffer, "\ncommitter ",
+		    sizeof(committer_buf), committer_buf, &ret->committer_mail,
+		    &ret->committer_time, &ret->committer_tz);
+
+	ret->summary = summary_buf;
+	tmp = strstr(commit->buffer, "\n\n");
+	if (!tmp) {
+	error_out:
+		sprintf(summary_buf, "(%s)", sha1_to_hex(commit->object.sha1));
+		return;
+	}
+	tmp += 2;
+	endp = strchr(tmp, '\n');
+	if (!endp)
+		goto error_out;
+	len = endp - tmp;
+	if (len >= sizeof(summary_buf))
+		goto error_out;
+	memcpy(summary_buf, tmp, len);
+	summary_buf[len] = 0;
+}
 
-    struct commit_list* list = get_commit_list(commit, filename);
-    sort_in_topological_order(&list, 1);
+static const char *format_time(unsigned long time, const char *tz_str,
+			       int show_raw_time)
+{
+	static char time_buf[128];
+	time_t t = time;
+	int minutes, tz;
+	struct tm *tm;
+
+	if (show_raw_time) {
+		sprintf(time_buf, "%lu %s", time, tz_str);
+		return time_buf;
+	}
+
+	tz = atoi(tz_str);
+	minutes = tz < 0 ? -tz : tz;
+	minutes = (minutes / 100)*60 + (minutes % 100);
+	minutes = tz < 0 ? -minutes : minutes;
+	t = time + minutes * 60;
+	tm = gmtime(&t);
+
+	strftime(time_buf, sizeof(time_buf), "%Y-%m-%d %H:%M:%S ", tm);
+	strcat(time_buf, tz_str);
+	return time_buf;
+}
 
-    if(fill_util_info(commit, filename)) {
-        printf("%s not found in %s\n", filename, argv[1]);
-        return 0;
-    }
-    alloc_line_map(commit);
+static void topo_setter(struct commit *c, void *data)
+{
+	struct util_info *util = c->util;
+	util->topo_data = data;
+}
 
-    struct util_info* util = commit->object.util;
-    num_blame_lines = util->num_lines;
-    blame_lines = xmalloc(sizeof(struct commit*)*num_blame_lines);
+static void *topo_getter(struct commit *c)
+{
+	struct util_info *util = c->util;
+	return util->topo_data;
+}
 
+static int read_ancestry(const char *graft_file,
+			 unsigned char **start_sha1)
+{
+	FILE *fp = fopen(graft_file, "r");
+	char buf[1024];
+	if (!fp)
+		return -1;
+	while (fgets(buf, sizeof(buf), fp)) {
+		/* The format is just "Commit Parent1 Parent2 ...\n" */
+		int len = strlen(buf);
+		struct commit_graft *graft = read_graft_line(buf, len);
+		register_commit_graft(graft, 0);
+		if (!*start_sha1)
+			*start_sha1 = graft->sha1;
+	}
+	fclose(fp);
+	return 0;
+}
 
-    for(i = 0; i < num_blame_lines; i++) {
-        blame_lines[i] = commit;
+static int lineno_width(int lines)
+{
+	int i, width;
 
-        ((struct util_info*) commit->object.util)->line_map[i] = i;
-    }
+	for (width = 1, i = 10; i <= lines + 1; width++)
+		i *= 10;
+	return width;
+}
 
-    process_commits(list, filename);
+static int find_orig_linenum(struct util_info *u, int lineno)
+{
+	int i;
 
-    for(i = 0; i < num_blame_lines; i++) {
-        printf("%d %s\n", i+1-1, sha1_to_hex(blame_lines[i]->object.sha1));
-//        printf("%d %s\n", i+1-1, find_unique_abbrev(blame_lines[i]->object.sha1, 6));
-    }
+	for (i = 0; i < u->num_lines; i++)
+		if (lineno == u->line_map[i])
+			return i + 1;
+	return 0;
+}
 
-    if(DEBUG) {
-        printf("num get patch: %d\n", num_get_patch);
-        printf("num commits: %d\n", num_commits);
-    }
+static void emit_meta(struct commit *c, int lno,
+		      int sha1_len, int compatibility, int porcelain,
+		      int show_name, int show_number, int show_raw_time,
+		      int longest_file, int longest_author,
+		      int max_digits, int max_orig_digits)
+{
+	struct util_info *u;
+	int lineno;
+	struct commit_info ci;
+
+	u = c->util;
+	lineno = find_orig_linenum(u, lno);
+
+	if (porcelain) {
+		int group_size = -1;
+		struct commit *cc = (lno == 0) ? NULL : blame_lines[lno-1];
+		if (cc != c) {
+			/* This is the beginning of this group */
+			int i;
+			for (i = lno + 1; i < num_blame_lines; i++)
+				if (blame_lines[i] != c)
+					break;
+			group_size = i - lno;
+		}
+		if (0 < group_size)
+			printf("%s %d %d %d\n", sha1_to_hex(c->object.sha1),
+			       lineno, lno + 1, group_size);
+		else
+			printf("%s %d %d\n", sha1_to_hex(c->object.sha1),
+			       lineno, lno + 1);
+		if (!u->meta_given) {
+			get_commit_info(c, &ci, 1);
+			printf("author %s\n", ci.author);
+			printf("author-mail %s\n", ci.author_mail);
+			printf("author-time %lu\n", ci.author_time);
+			printf("author-tz %s\n", ci.author_tz);
+			printf("committer %s\n", ci.committer);
+			printf("committer-mail %s\n", ci.committer_mail);
+			printf("committer-time %lu\n", ci.committer_time);
+			printf("committer-tz %s\n", ci.committer_tz);
+			printf("filename ");
+			if (quote_c_style(u->pathname, NULL, NULL, 0))
+				quote_c_style(u->pathname, NULL, stdout, 0);
+			else
+				fputs(u->pathname, stdout);
+			printf("\nsummary %s\n", ci.summary);
+
+			u->meta_given = 1;
+		}
+		putchar('\t');
+		return;
+	}
+
+	get_commit_info(c, &ci, 0);
+	fwrite(sha1_to_hex(c->object.sha1), sha1_len, 1, stdout);
+	if (compatibility) {
+		printf("\t(%10s\t%10s\t%d)", ci.author,
+		       format_time(ci.author_time, ci.author_tz,
+				   show_raw_time),
+		       lno + 1);
+	}
+	else {
+		if (show_name)
+			printf(" %-*.*s", longest_file, longest_file,
+			       u->pathname);
+		if (show_number)
+			printf(" %*d", max_orig_digits,
+			       lineno);
+		printf(" (%-*.*s %10s %*d) ",
+		       longest_author, longest_author, ci.author,
+		       format_time(ci.author_time, ci.author_tz,
+				   show_raw_time),
+		       max_digits, lno + 1);
+	}
+}
 
-    return 0;
+int main(int argc, const char **argv)
+{
+	int i;
+	struct commit *initial = NULL;
+	unsigned char sha1[20], *sha1_p = NULL;
+
+	const char *filename = NULL, *commit = NULL;
+	char filename_buf[256];
+	int sha1_len = 8;
+	int compatibility = 0;
+	int show_raw_time = 0;
+	int options = 1;
+	struct commit *start_commit;
+
+	const char *args[10];
+	struct rev_info rev;
+
+	struct commit_info ci;
+	const char *buf;
+	int max_digits, max_orig_digits;
+	int longest_file, longest_author, longest_file_lines;
+	int show_name = 0;
+	int show_number = 0;
+	int porcelain = 0;
+
+	const char *prefix = setup_git_directory();
+	git_config(git_default_config);
+
+	for (i = 1; i < argc; i++) {
+		if (options) {
+			if (!strcmp(argv[i], "-h") ||
+			   !strcmp(argv[i], "--help"))
+				usage(blame_usage);
+			if (!strcmp(argv[i], "-l") ||
+			    !strcmp(argv[i], "--long")) {
+				sha1_len = 40;
+				continue;
+			}
+			if (!strcmp(argv[i], "-c") ||
+			    !strcmp(argv[i], "--compatibility")) {
+				compatibility = 1;
+				continue;
+			}
+			if (!strcmp(argv[i], "-t") ||
+			    !strcmp(argv[i], "--time")) {
+				show_raw_time = 1;
+				continue;
+			}
+			if (!strcmp(argv[i], "-S")) {
+				if (i + 1 < argc &&
+				    !read_ancestry(argv[i + 1], &sha1_p)) {
+					compatibility = 1;
+					i++;
+					continue;
+				}
+				usage(blame_usage);
+			}
+			if (!strcmp(argv[i], "-f") ||
+			    !strcmp(argv[i], "--show-name")) {
+				show_name = 1;
+				continue;
+			}
+			if (!strcmp(argv[i], "-n") ||
+			    !strcmp(argv[i], "--show-number")) {
+				show_number = 1;
+				continue;
+			}
+			if (!strcmp(argv[i], "-p") ||
+			    !strcmp(argv[i], "--porcelain")) {
+				porcelain = 1;
+				sha1_len = 40;
+				show_raw_time = 1;
+				continue;
+			}
+			if (!strcmp(argv[i], "--")) {
+				options = 0;
+				continue;
+			}
+			if (argv[i][0] == '-')
+				usage(blame_usage);
+			options = 0;
+		}
+
+		if (!options) {
+			if (!filename)
+				filename = argv[i];
+			else if (!commit)
+				commit = argv[i];
+			else
+				usage(blame_usage);
+		}
+	}
+
+	if (!filename)
+		usage(blame_usage);
+	if (commit && sha1_p)
+		usage(blame_usage);
+	else if (!commit)
+		commit = "HEAD";
+
+	if (prefix)
+		sprintf(filename_buf, "%s%s", prefix, filename);
+	else
+		strcpy(filename_buf, filename);
+	filename = filename_buf;
+
+	if (!sha1_p) {
+		if (get_sha1(commit, sha1))
+			die("get_sha1 failed, commit '%s' not found", commit);
+		sha1_p = sha1;
+	}
+	start_commit = lookup_commit_reference(sha1_p);
+	get_util(start_commit)->pathname = filename;
+	if (fill_util_info(start_commit)) {
+		printf("%s not found in %s\n", filename, commit);
+		return 1;
+	}
+
+	init_revisions(&rev, setup_git_directory());
+	rev.remove_empty_trees = 1;
+	rev.topo_order = 1;
+	rev.prune_fn = simplify_commit;
+	rev.topo_setter = topo_setter;
+	rev.topo_getter = topo_getter;
+	rev.parents = 1;
+	rev.limited = 1;
+
+	commit_list_insert(start_commit, &rev.commits);
+
+	args[0] = filename;
+	args[1] = NULL;
+	diff_tree_setup_paths(args, &rev.pruning);
+	prepare_revision_walk(&rev);
+	process_commits(&rev, filename, &initial);
+
+	for (i = 0; i < num_blame_lines; i++)
+		if (!blame_lines[i])
+			blame_lines[i] = initial;
+
+	buf = blame_contents;
+	max_digits = lineno_width(num_blame_lines);
+
+	longest_file = 0;
+	longest_author = 0;
+	longest_file_lines = 0;
+	for (i = 0; i < num_blame_lines; i++) {
+		struct commit *c = blame_lines[i];
+		struct util_info *u;
+		u = c->util;
+
+		if (!show_name && strcmp(filename, u->pathname))
+			show_name = 1;
+		if (longest_file < strlen(u->pathname))
+			longest_file = strlen(u->pathname);
+		if (longest_file_lines < u->num_lines)
+			longest_file_lines = u->num_lines;
+		get_commit_info(c, &ci, 0);
+		if (longest_author < strlen(ci.author))
+			longest_author = strlen(ci.author);
+	}
+
+	max_orig_digits = lineno_width(longest_file_lines);
+
+	for (i = 0; i < num_blame_lines; i++) {
+		emit_meta(blame_lines[i], i,
+			  sha1_len, compatibility, porcelain,
+			  show_name, show_number, show_raw_time,
+			  longest_file, longest_author,
+			  max_digits, max_orig_digits);
+
+		if (i == num_blame_lines - 1) {
+			fwrite(buf, blame_len - (buf - blame_contents),
+			       1, stdout);
+			if (blame_contents[blame_len-1] != '\n')
+				putc('\n', stdout);
+		}
+		else {
+			char *next_buf = strchr(buf, '\n') + 1;
+			fwrite(buf, next_buf - buf, 1, stdout);
+			buf = next_buf;
+		}
+	}
+
+	if (DEBUG) {
+		printf("num get patch: %d\n", num_get_patch);
+		printf("num commits: %d\n", num_commits);
+		printf("patch time: %f\n", patch_time / 1000000.0);
+		printf("initial: %s\n", sha1_to_hex(initial->object.sha1));
+	}
+
+	return 0;
 }