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index 85d7965daa09d01f05a65f5bdde8d889fd21744b..be1639e80e1e4c42c0e1d699b3b83661cc133d69 100644 (file)
--- a/apply.c
+++ b/apply.c
static int merge_patch = 1;
static const char apply_usage[] = "git-apply <patch>";
+/*
+ * Various "current state", notably line numbers and what
+ * file (and how) we're patching right now.. The "is_xxxx"
+ * things are flags, where -1 means "don't know yet".
+ */
+static int linenr = 1;
+static int old_mode, new_mode;
+static char *old_name, *new_name, *def_name;
+static int is_rename, is_copy, is_new, is_delete;
+
#define CHUNKSIZE (8192)
+#define SLOP (16)
static void *read_patch_file(int fd, unsigned long *sizep)
{
size += nr;
}
*sizep = size;
+
+ /*
+ * Make sure that we have some slop in the buffer
+ * so that we can do speculative "memcmp" etc, and
+ * see to it that it is NUL-filled.
+ */
+ if (alloc < size + SLOP)
+ buffer = xrealloc(buffer, size + SLOP);
+ memset(buffer + size, 0, SLOP);
return buffer;
}
return len;
}
-static int match_word(const char *line, const char *match)
+static int is_dev_null(const char *str)
+{
+ return !memcmp("/dev/null", str, 9) && isspace(str[9]);
+}
+
+#define TERM_EXIST 1
+#define TERM_SPACE 2
+#define TERM_TAB 4
+
+static int name_terminate(const char *name, int namelen, int c, int terminate)
+{
+ if (c == ' ' && !(terminate & TERM_SPACE))
+ return 0;
+ if (c == '\t' && !(terminate & TERM_TAB))
+ return 0;
+
+ /*
+ * Do we want an existing name? Return false and
+ * continue if it's not there.
+ */
+ if (terminate & TERM_EXIST)
+ return cache_name_pos(name, namelen) >= 0;
+
+ return 1;
+}
+
+static char * find_name(const char *line, char *def, int p_value, int terminate)
+{
+ int len;
+ const char *start = line;
+ char *name;
+
+ for (;;) {
+ char c = *line;
+
+ if (isspace(c)) {
+ if (c == '\n')
+ break;
+ if (name_terminate(start, line-start, c, terminate))
+ break;
+ }
+ line++;
+ if (c == '/' && !--p_value)
+ start = line;
+ }
+ if (!start)
+ return def;
+ len = line - start;
+ if (!len)
+ return def;
+
+ /*
+ * Generally we prefer the shorter name, especially
+ * if the other one is just a variation of that with
+ * something else tacked on to the end (ie "file.orig"
+ * or "file~").
+ */
+ if (def) {
+ int deflen = strlen(def);
+ if (deflen < len && !strncmp(start, def, deflen))
+ return def;
+ }
+
+ name = xmalloc(len + 1);
+ memcpy(name, start, len);
+ name[len] = 0;
+ free(def);
+ return name;
+}
+
+/*
+ * Get the name etc info from the --/+++ lines of a traditional patch header
+ *
+ * NOTE! This hardcodes "-p1" behaviour in filename detection.
+ *
+ * FIXME! The end-of-filename heuristics are kind of screwy. For existing
+ * files, we can happily check the index for a match, but for creating a
+ * new file we should try to match whatever "patch" does. I have no idea.
+ */
+static void parse_traditional_patch(const char *first, const char *second)
+{
+ int p_value = 1;
+ char *name;
+
+ first += 4; // skip "--- "
+ second += 4; // skip "+++ "
+ if (is_dev_null(first)) {
+ is_new = 1;
+ name = find_name(second, def_name, p_value, TERM_SPACE | TERM_TAB);
+ new_name = name;
+ } else if (is_dev_null(second)) {
+ is_delete = 1;
+ name = find_name(first, def_name, p_value, TERM_EXIST | TERM_SPACE | TERM_TAB);
+ old_name = name;
+ } else {
+ name = find_name(first, def_name, p_value, TERM_EXIST | TERM_SPACE | TERM_TAB);
+ name = find_name(second, name, p_value, TERM_EXIST | TERM_SPACE | TERM_TAB);
+ old_name = new_name = name;
+ }
+ if (!name)
+ die("unable to find filename in patch at line %d", linenr);
+}
+
+static int gitdiff_hdrend(const char *line)
+{
+ return -1;
+}
+
+/*
+ * We're anal about diff header consistency, to make
+ * sure that we don't end up having strange ambiguous
+ * patches floating around.
+ *
+ * As a result, gitdiff_{old|new}name() will check
+ * their names against any previous information, just
+ * to make sure..
+ */
+static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
{
+ int len;
+ const char *name;
+
+ if (!orig_name && !isnull)
+ return find_name(line, NULL, 1, 0);
+
+ name = "/dev/null";
+ len = 9;
+ if (orig_name) {
+ name = orig_name;
+ len = strlen(name);
+ if (isnull)
+ die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
+ }
+
+ if (*name == '/')
+ goto absolute_path;
+
for (;;) {
- char c = *match++;
- if (!c)
+ char c = *line++;
+ if (c == '\n')
break;
- if (*line++ != c)
- return 0;
+ if (c != '/')
+ continue;
+absolute_path:
+ if (memcmp(line, name, len) || line[len] != '\n')
+ break;
+ return orig_name;
}
- return *line == ' ';
+ die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
+ return NULL;
+}
+
+static int gitdiff_oldname(const char *line)
+{
+ old_name = gitdiff_verify_name(line, is_new, old_name, "old");
+ return 0;
+}
+
+static int gitdiff_newname(const char *line)
+{
+ new_name = gitdiff_verify_name(line, is_delete, new_name, "new");
+ return 0;
+}
+
+static int gitdiff_oldmode(const char *line)
+{
+ old_mode = strtoul(line, NULL, 8);
+ return 0;
+}
+
+static int gitdiff_newmode(const char *line)
+{
+ new_mode = strtoul(line, NULL, 8);
+ return 0;
+}
+
+static int gitdiff_delete(const char *line)
+{
+ is_delete = 1;
+ return gitdiff_oldmode(line);
+}
+
+static int gitdiff_newfile(const char *line)
+{
+ is_new = 1;
+ return gitdiff_newmode(line);
+}
+
+static int gitdiff_copysrc(const char *line)
+{
+ is_copy = 1;
+ old_name = find_name(line, NULL, 0, 0);
+ return 0;
+}
+
+static int gitdiff_copydst(const char *line)
+{
+ is_copy = 1;
+ new_name = find_name(line, NULL, 0, 0);
+ return 0;
+}
+
+static int gitdiff_renamesrc(const char *line)
+{
+ is_rename = 1;
+ old_name = find_name(line, NULL, 0, 0);
+ return 0;
+}
+
+static int gitdiff_renamedst(const char *line)
+{
+ is_rename = 1;
+ new_name = find_name(line, NULL, 0, 0);
+ return 0;
+}
+
+static int gitdiff_similarity(const char *line)
+{
+ return 0;
+}
+
+/*
+ * This is normal for a diff that doesn't change anything: we'll fall through
+ * into the next diff. Tell the parser to break out.
+ */
+static int gitdiff_unrecognized(const char *line)
+{
+ return -1;
}
/* Verify that we recognize the lines following a git header */
-static int parse_git_header(char *line, unsigned int size)
+static int parse_git_header(char *line, int len, unsigned int size)
{
- unsigned long offset, len;
+ unsigned long offset;
+
+ /* A git diff has explicit new/delete information, so we don't guess */
+ is_new = 0;
+ is_delete = 0;
+
+ line += len;
+ size -= len;
+ linenr++;
+ for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
+ static const struct opentry {
+ const char *str;
+ int (*fn)(const char *);
+ } optable[] = {
+ { "@@ -", gitdiff_hdrend },
+ { "--- ", gitdiff_oldname },
+ { "+++ ", gitdiff_newname },
+ { "old mode ", gitdiff_oldmode },
+ { "new mode ", gitdiff_newmode },
+ { "deleted file mode ", gitdiff_delete },
+ { "new file mode ", gitdiff_newfile },
+ { "copy from ", gitdiff_copysrc },
+ { "copy to ", gitdiff_copydst },
+ { "rename from ", gitdiff_renamesrc },
+ { "rename to ", gitdiff_renamedst },
+ { "similarity index ", gitdiff_similarity },
+ { "", gitdiff_unrecognized },
+ };
+ int i;
- for (offset = 0 ; size > 0 ; offset += len, size -= len, line += len) {
len = linelen(line, size);
- if (!len)
+ if (!len || line[len-1] != '\n')
break;
- if (line[len-1] != '\n')
- return -1;
- if (len < 4)
+ for (i = 0; i < sizeof(optable) / sizeof(optable[0]); i++) {
+ const struct opentry *p = optable + i;
+ int oplen = strlen(p->str);
+ if (len < oplen || memcmp(p->str, line, oplen))
+ continue;
+ if (p->fn(line + oplen) < 0)
+ return offset;
break;
- if (!memcmp(line, "@@ -", 4))
- return offset;
- if (match_word(line, "new file mode"))
- continue;
- if (match_word(line, "deleted file mode"))
- continue;
- if (match_word(line, "copy"))
- continue;
- if (match_word(line, "rename"))
- continue;
- if (match_word(line, "similarity index"))
- continue;
- break;
+ }
}
- /* We want either a patch _or_ something real */
- return offset ? :-1;
+ return offset;
+}
+
+static int parse_num(const char *line, int len, int offset, const char *expect, unsigned long *p)
+{
+ char *ptr;
+ int digits, ex;
+
+ if (offset < 0 || offset >= len)
+ return -1;
+ line += offset;
+ len -= offset;
+
+ if (!isdigit(*line))
+ return -1;
+ *p = strtoul(line, &ptr, 10);
+
+ digits = ptr - line;
+
+ offset += digits;
+ line += digits;
+ len -= digits;
+
+ ex = strlen(expect);
+ if (ex > len)
+ return -1;
+ if (memcmp(line, expect, ex))
+ return -1;
+
+ return offset + ex;
+}
+
+/*
+ * Parse a unified diff fragment header of the
+ * form "@@ -a,b +c,d @@"
+ */
+static int parse_fragment_header(char *line, int len, unsigned long *pos)
+{
+ int offset;
+
+ if (!len || line[len-1] != '\n')
+ return -1;
+
+ /* Figure out the number of lines in a fragment */
+ offset = parse_num(line, len, 4, ",", pos);
+ offset = parse_num(line, len, offset, " +", pos+1);
+ offset = parse_num(line, len, offset, ",", pos+2);
+ offset = parse_num(line, len, offset, " @@", pos+3);
+
+ return offset;
}
static int find_header(char *line, unsigned long size, int *hdrsize)
{
unsigned long offset, len;
- for (offset = 0; size > 0; offset += len, size -= len, line += len) {
+ is_rename = is_copy = 0;
+ is_new = is_delete = -1;
+ old_mode = new_mode = 0;
+ def_name = old_name = new_name = NULL;
+ for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
unsigned long nextlen;
len = linelen(line, size);
/* Testing this early allows us to take a few shortcuts.. */
if (len < 6)
continue;
+
+ /*
+ * Make sure we don't find any unconnected patch fragmants.
+ * That's a sign that we didn't find a header, and that a
+ * patch has become corrupted/broken up.
+ */
+ if (!memcmp("@@ -", line, 4)) {
+ unsigned long pos[4];
+ if (parse_fragment_header(line, len, pos) < 0)
+ continue;
+ error("patch fragment without header at line %d: %.*s", linenr, len-1, line);
+ }
+
if (size < len + 6)
break;
* or mode change, so we handle that specially
*/
if (!memcmp("diff --git ", line, 11)) {
- int git_hdr_len = parse_git_header(line + len, size - len);
+ int git_hdr_len = parse_git_header(line, len, size);
if (git_hdr_len < 0)
continue;
- *hdrsize = len + git_hdr_len;
+ *hdrsize = git_hdr_len;
return offset;
}
continue;
/* Ok, we'll consider it a patch */
+ parse_traditional_patch(line, line+len);
*hdrsize = len + nextlen;
+ linenr += 2;
return offset;
}
return -1;
}
-static int parse_num(const char *line, int len, int offset, const char *expect, unsigned long *p)
-{
- char *ptr;
- int digits, ex;
-
- if (offset < 0 || offset >= len)
- return -1;
- line += offset;
- len -= offset;
-
- if (!isdigit(*line))
- return -1;
- *p = strtoul(line, &ptr, 10);
-
- digits = ptr - line;
-
- offset += digits;
- line += digits;
- len -= digits;
-
- ex = strlen(expect);
- if (ex > len)
- return -1;
- if (memcmp(line, expect, ex))
- return -1;
-
- return offset + ex;
-}
-
/*
* Parse a unified diff. Note that this really needs
* to parse each fragment separately, since the only
@@ -193,23 +488,24 @@ static int parse_num(const char *line, int len, int offset, const char *expect,
static int apply_fragment(char *line, unsigned long size)
{
int len = linelen(line, size), offset;
- unsigned long oldpos, oldlines, newpos, newlines;
+ unsigned long pos[4], oldlines, newlines;
- if (!len || line[len-1] != '\n')
- return -1;
-
- /* Figure out the number of lines in a fragment */
- offset = parse_num(line, len, 4, ",", &oldpos);
- offset = parse_num(line, len, offset, " +", &oldlines);
- offset = parse_num(line, len, offset, ",", &newpos);
- offset = parse_num(line, len, offset, " @@", &newlines);
+ offset = parse_fragment_header(line, len, pos);
if (offset < 0)
return -1;
+ oldlines = pos[1];
+ newlines = pos[3];
+
+ if (is_new < 0 && (pos[0] || oldlines))
+ is_new = 0;
+ if (is_delete < 0 && (pos[1] || newlines))
+ is_delete = 0;
/* Parse the thing.. */
line += len;
size -= len;
- for (offset = len; size > 0; offset += len, size -= len, line += len) {
+ linenr++;
+ for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
if (!oldlines && !newlines)
break;
len = linelen(line, size);
while (size > 4 && !memcmp(line, "@@ -", 4)) {
int len = apply_fragment(line, size);
if (len <= 0)
- break;
+ die("corrupt patch at line %d", linenr);
printf("applying fragment:\n%.*s\n\n", len, line);
header = buffer + offset;
printf("Found header:\n%.*s\n\n", hdrsize, header);
+printf("Rename: %d\n", is_rename);
+printf("Copy: %d\n", is_copy);
+printf("New: %d\n", is_new);
+printf("Delete: %d\n", is_delete);
+printf("Mode: %o:%o\n", old_mode, new_mode);
+printf("Name: '%s':'%s'\n", old_name, new_name);
+
+ if (old_name && cache_name_pos(old_name, strlen(old_name)) < 0)
+ die("file %s does not exist", old_name);
+ if (new_name && (is_new | is_rename | is_copy)) {
+ if (cache_name_pos(new_name, strlen(new_name)) >= 0)
+ die("file %s already exists", new_name);
+ }
patch = header + hdrsize;
patchsize = apply_single_patch(patch, size - offset - hdrsize);
int main(int argc, char **argv)
{
int i;
+ int read_stdin = 1;
if (read_cache() < 0)
die("unable to read index file");
if (!strcmp(arg, "-")) {
apply_patch(0);
+ read_stdin = 0;
continue;
}
if (!strcmp(arg, "--no-merge")) {
fd = open(arg, O_RDONLY);
if (fd < 0)
usage(apply_usage);
+ read_stdin = 0;
apply_patch(fd);
close(fd);
}
+ if (read_stdin)
+ apply_patch(0);
return 0;
}