mergetool-lib: make the three-way diff the default for vim/gvim

diff --git a/sha1_file.c b/sha1_file.c
index 1efa9154eda4e1ec064d627dfb21c876c914f4d7..0cd9435619f1e0637584289b45d52c1cdd8a9460 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -102,20 +102,22 @@ static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
  */
 char *sha1_file_name(const unsigned char *sha1)
 {
-       static char *name, *base;
+       static char buf[PATH_MAX];
+       const char *objdir;
+       int len;
 
-       if (!base) {
-               const char *sha1_file_directory = get_object_directory();
-               int len = strlen(sha1_file_directory);
-               base = xmalloc(len + 60);
-               memcpy(base, sha1_file_directory, len);
-               memset(base+len, 0, 60);
-               base[len] = '/';
-               base[len+3] = '/';
-               name = base + len + 1;
-       }
-       fill_sha1_path(name, sha1);
-       return base;
+       objdir = get_object_directory();
+       len = strlen(objdir);
+
+       /* '/' + sha1(2) + '/' + sha1(38) + '\0' */
+       if (len + 43 > PATH_MAX)
+               die("insanely long object directory %s", objdir);
+       memcpy(buf, objdir, len);
+       buf[len] = '/';
+       buf[len+3] = '/';
+       buf[len+42] = '\0';
+       fill_sha1_path(buf + len + 1, sha1);
+       return buf;
 }
 
 static char *sha1_get_pack_name(const unsigned char *sha1,
@@ -2084,6 +2086,7 @@ void *read_sha1_file_repl(const unsigned char *sha1,
 {
        const unsigned char *repl = lookup_replace_object(sha1);
        void *data = read_object(repl, type, size);
+       char *path;
 
        /* die if we replaced an object with one that does not exist */
        if (!data && repl != sha1)
@@ -2091,8 +2094,16 @@ void *read_sha1_file_repl(const unsigned char *sha1,
                    sha1_to_hex(repl), sha1_to_hex(sha1));
 
        /* legacy behavior is to die on corrupted objects */
-       if (!data && (has_loose_object(repl) || has_packed_and_bad(repl)))
-               die("object %s is corrupted", sha1_to_hex(repl));
+       if (!data) {
+               if (has_loose_object(repl)) {
+                       path = sha1_file_name(sha1);
+                       die("loose object %s (stored in %s) is corrupted", sha1_to_hex(repl), path);
+               }
+               if (has_packed_and_bad(repl)) {
+                       path = sha1_pack_name(sha1);
+                       die("packed object %s (stored in %s) is corrupted", sha1_to_hex(repl), path);
+               }
+       }
 
        if (replacement)
                *replacement = repl;
@@ -2523,3 +2534,13 @@ int read_pack_header(int fd, struct pack_header *header)
                return PH_ERROR_PROTOCOL;
        return 0;
 }
+
+void assert_sha1_type(const unsigned char *sha1, enum object_type expect)
+{
+       enum object_type type = sha1_object_info(sha1, NULL);
+       if (type < 0)
+               die("%s is not a valid object", sha1_to_hex(sha1));
+       if (type != expect)
+               die("%s is not a valid '%s' object", sha1_to_hex(sha1),
+                   typename(expect));
+}