From b28858bf65d4fd6d8bb070865518ec43817fe7f3 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Thu, 5 May 2005 16:10:21 -0700 Subject: [PATCH] Update diff engine for symlinks stored in the cache. This patch updates the external diff interface engine for the change to store the symbolic links in the cache, recently done by Kay Sievers. The main thing it does is when comparing with the work tree, it prepares the counterpart to the blob being compared by doing a readlink followed by sending that result to a temporary file to be diffed. Signed-off-by: Junio C Hamano --- diff.c | 78 +++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 56 insertions(+), 22 deletions(-) diff --git a/diff.c b/diff.c index 8dfa62443..95488cdd9 100644 --- a/diff.c +++ b/diff.c @@ -125,9 +125,16 @@ static void builtin_diff(const char *name, printf("Created: %s (mode:%s)\n", name, temp[1].mode); else if (!path1[1][0]) printf("Deleted: %s\n", name); - else if (strcmp(temp[0].mode, temp[1].mode)) + else if (strcmp(temp[0].mode, temp[1].mode)) { printf("Mode changed: %s (%s->%s)\n", name, temp[0].mode, temp[1].mode); + /* Be careful. We do not want to diff between + * symlink and a file. + */ + if (strncmp(temp[0].mode, "120", 3) != + strncmp(temp[1].mode, "120", 3)) + exit(0); + } fflush(NULL); execlp("/bin/sh","sh", "-c", cmd, NULL); } @@ -163,13 +170,35 @@ static int work_tree_matches(const char *name, const unsigned char *sha1) if (pos < 0) return 0; ce = active_cache[pos]; - if ((stat(name, &st) < 0) || + if ((lstat(name, &st) < 0) || + !S_ISREG(st.st_mode) || cache_match_stat(ce, &st) || memcmp(sha1, ce->sha1, 20)) return 0; return 1; } +static void prep_temp_blob(struct diff_tempfile *temp, + void *blob, + unsigned long size, + unsigned char *sha1, + int mode) +{ + int fd; + + strcpy(temp->tmp_path, ".diff_XXXXXX"); + fd = mkstemp(temp->tmp_path); + 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_spec *one) @@ -196,20 +225,36 @@ static void prepare_temp_file(const char *name, if (!one->sha1_valid || use_work_tree) { struct stat st; temp->name = name; - if (stat(temp->name, &st) < 0) { + if (lstat(temp->name, &st) < 0) { if (errno == ENOENT) goto not_a_valid_file; die("stat(%s): %s", temp->name, strerror(errno)); } - if (!one->sha1_valid) - strcpy(temp->hex, sha1_to_hex(null_sha1)); - else - strcpy(temp->hex, sha1_to_hex(one->blob_sha1)); - sprintf(temp->mode, "%06o", - S_IFREG |ce_permissions(st.st_mode)); + if (S_ISLNK(st.st_mode)) { + int ret; + char *buf, buf_[1024]; + buf = ((sizeof(buf_) < st.st_size) ? + xmalloc(st.st_size) : buf_); + 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->blob_sha1 : null_sha1), + (one->sha1_valid ? + one->mode : S_IFLNK)); + } + else { + if (!one->sha1_valid) + strcpy(temp->hex, sha1_to_hex(null_sha1)); + else + strcpy(temp->hex, sha1_to_hex(one->blob_sha1)); + sprintf(temp->mode, "%06o", + S_IFREG |ce_permissions(st.st_mode)); + } + return; } else { - int fd; void *blob; char type[20]; unsigned long size; @@ -218,19 +263,8 @@ static void prepare_temp_file(const char *name, if (!blob || strcmp(type, "blob")) die("unable to read blob object for %s (%s)", name, sha1_to_hex(one->blob_sha1)); - - strcpy(temp->tmp_path, ".diff_XXXXXX"); - fd = mkstemp(temp->tmp_path); - if (fd < 0) - die("unable to create temp-file"); - if (write(fd, blob, size) != size) - die("unable to write temp-file"); - close(fd); + prep_temp_blob(temp, blob, size, one->blob_sha1, one->mode); free(blob); - temp->name = temp->tmp_path; - strcpy(temp->hex, sha1_to_hex(one->blob_sha1)); - temp->hex[40] = 0; - sprintf(temp->mode, "%06o", one->mode); } } -- 2.26.2