signed push: remove duplicated protocol info

diff --git a/read-cache.c b/read-cache.c
index 12335a362b035340118dd8e0b202a95ad16d9b00..5d3c8bd4aaffda9915a3fd62d9d9800f4ac8baff 100644 (file)
--- a/read-cache.c
+++ b/read-cache.c
@@ -434,18 +434,26 @@ int df_name_compare(const char *name1, int len1, int mode1,
        return c1 - c2;
 }
 
-int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2)
+int name_compare(const char *name1, size_t len1, const char *name2, size_t len2)
 {
-       int len = len1 < len2 ? len1 : len2;
-       int cmp;
-
-       cmp = memcmp(name1, name2, len);
+       size_t min_len = (len1 < len2) ? len1 : len2;
+       int cmp = memcmp(name1, name2, min_len);
        if (cmp)
                return cmp;
        if (len1 < len2)
                return -1;
        if (len1 > len2)
                return 1;
+       return 0;
+}
+
+int cache_name_stage_compare(const char *name1, int len1, int stage1, const char *name2, int len2, int stage2)
+{
+       int cmp;
+
+       cmp = name_compare(name1, len1, name2, len2);
+       if (cmp)
+               return cmp;
 
        if (stage1 < stage2)
                return -1;
@@ -454,11 +462,6 @@ int cache_name_stage_compare(const char *name1, int len1, int stage1, const char
        return 0;
 }
 
-int cache_name_compare(const char *name1, int len1, const char *name2, int len2)
-{
-       return cache_name_stage_compare(name1, len1, 0, name2, len2, 0);
-}
-
 static int index_name_stage_pos(const struct index_state *istate, const char *name, int namelen, int stage)
 {
        int first, last;
@@ -1463,8 +1466,7 @@ static struct cache_entry *create_from_disk(struct ondisk_cache_entry *ondisk,
 }
 
 /* remember to discard_cache() before reading a different cache! */
-static int do_read_index(struct index_state *istate, const char *path,
-                        int must_exist)
+int do_read_index(struct index_state *istate, const char *path, int must_exist)
 {
        int fd, i;
        struct stat st;
@@ -1839,6 +1841,50 @@ static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce,
        return result;
 }
 
+/*
+ * This function verifies if index_state has the correct sha1 of the
+ * index file.  Don't die if we have any other failure, just return 0.
+ */
+static int verify_index_from(const struct index_state *istate, const char *path)
+{
+       int fd;
+       ssize_t n;
+       struct stat st;
+       unsigned char sha1[20];
+
+       if (!istate->initialized)
+               return 0;
+
+       fd = open(path, O_RDONLY);
+       if (fd < 0)
+               return 0;
+
+       if (fstat(fd, &st))
+               goto out;
+
+       if (st.st_size < sizeof(struct cache_header) + 20)
+               goto out;
+
+       n = pread_in_full(fd, sha1, 20, st.st_size - 20);
+       if (n != 20)
+               goto out;
+
+       if (hashcmp(istate->sha1, sha1))
+               goto out;
+
+       close(fd);
+       return 1;
+
+out:
+       close(fd);
+       return 0;
+}
+
+static int verify_index(const struct index_state *istate)
+{
+       return verify_index_from(istate, get_index_file());
+}
+
 static int has_racy_timestamp(struct index_state *istate)
 {
        int entries = istate->cache_nr;
@@ -1858,6 +1904,7 @@ static int has_racy_timestamp(struct index_state *istate)
 void update_index_if_able(struct index_state *istate, struct lock_file *lockfile)
 {
        if ((istate->cache_changed || has_racy_timestamp(istate)) &&
+           verify_index(istate) &&
            write_locked_index(istate, lockfile, COMMIT_LOCK))
                rollback_lock_file(lockfile);
 }