Add documentation for the rest of commands.

diff --git a/update-cache.c b/update-cache.c
index bb25fa114c1017380c8441f514ae2e66beef1e68..893ba8679d5764ba84627558d567268ff2500558 100644 (file)
--- a/update-cache.c
+++ b/update-cache.c
@@ -15,6 +15,12 @@
  */
 static int allow_add = 0, allow_remove = 0, not_new = 0;
 
+/*
+ * update-cache --refresh may not touch anything at all, in which case
+ * writing 1.6MB of the same thing is a waste.
+ */
+static int cache_changed = 0;
+
 /* Three functions to allow overloaded pointer return; see linux/err.h */
 static inline void *ERR_PTR(long error)
 {
@@ -51,25 +57,22 @@ static void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
        ce->ce_size = htonl(st->st_size);
 }
 
-static int add_file_to_cache(char *path)
+static int add_file_to_cache_1(char *path)
 {
        int size, namelen;
        struct cache_entry *ce;
        struct stat st;
        int fd;
+       unsigned int len;
+       char target[1024];
 
-       fd = open(path, O_RDONLY);
-       if (fd < 0) {
+       if (lstat(path, &st) < 0) {
                if (errno == ENOENT || errno == ENOTDIR) {
                        if (allow_remove)
                                return remove_file_from_cache(path);
                }
                return -1;
        }
-       if (fstat(fd, &st) < 0) {
-               close(fd);
-               return -1;
-       }
        namelen = strlen(path);
        size = cache_entry_size(namelen);
        ce = xmalloc(size);
@@ -78,13 +81,53 @@ static int add_file_to_cache(char *path)
        fill_stat_cache_info(ce, &st);
        ce->ce_mode = create_ce_mode(st.st_mode);
        ce->ce_flags = htons(namelen);
-
-       if (index_fd(ce->sha1, fd, &st) < 0)
+       switch (st.st_mode & S_IFMT) {
+       case S_IFREG:
+               fd = open(path, O_RDONLY);
+               if (fd < 0)
+                       return -1;
+               if (index_fd(ce->sha1, fd, &st) < 0)
+                       return -1;
+               break;
+       case S_IFLNK:
+               len = readlink(path, target, sizeof(target));
+               if (len == -1 || len+1 > sizeof(target))
+                       return -1;
+               if (write_sha1_file(target, len, "blob", ce->sha1))
+                       return -1;
+               break;
+       default:
                return -1;
-
+       }
+       if (!cache_changed) {
+               /* If we have not smudged the cache, be careful
+                * to keep it clean.  Find out if we have a matching
+                * cache entry that add_cache_entry would replace with,
+                * and if it matches then do not bother calling it.
+                */
+               int pos = cache_name_pos(ce->name, namelen);
+               if ((0 <= pos) &&
+                   !memcmp(active_cache[pos], ce, sizeof(*ce))) {
+                       free(ce);
+                       /* magic to tell add_file_to_cache that
+                        * we have not updated anything.
+                        */
+                       return 999;
+               }
+       }
        return add_cache_entry(ce, allow_add);
 }
 
+static int add_file_to_cache(char *path)
+{
+       int ret = add_file_to_cache_1(path);
+       if (ret == 0)
+               cache_changed = 1;
+       else if (ret == 999)
+               ret = 0;
+       return ret;
+}
+
 static int match_data(int fd, void *buffer, unsigned long size)
 {
        while (size) {
@@ -137,7 +180,7 @@ static struct cache_entry *refresh_entry(struct cache_entry *ce)
        struct cache_entry *updated;
        int changed, size;
 
-       if (stat(ce->name, &st) < 0)
+       if (lstat(ce->name, &st) < 0)
                return ERR_PTR(-errno);
 
        changed = cache_match_stat(ce, &st);
@@ -145,15 +188,16 @@ static struct cache_entry *refresh_entry(struct cache_entry *ce)
                return ce;
 
        /*
-        * If the mode has changed, there's no point in trying
+        * If the mode or type has changed, there's no point in trying
         * to refresh the entry - it's not going to match
         */
-       if (changed & MODE_CHANGED)
+       if (changed & (MODE_CHANGED | TYPE_CHANGED))
                return ERR_PTR(-EINVAL);
 
        if (compare_data(ce, st.st_size))
                return ERR_PTR(-EINVAL);
 
+       cache_changed = 1;
        size = ce_size(ce);
        updated = xmalloc(size);
        memcpy(updated, ce, size);
@@ -234,6 +278,7 @@ static int add_cacheinfo(char *arg1, char *arg2, char *arg3)
        if (!verify_path(arg3))
                return -1;
 
+       cache_changed = 1;
        len = strlen(arg3);
        size = cache_entry_size(len);
        ce = xmalloc(size);
@@ -328,9 +373,13 @@ int main(int argc, char **argv)
                if (add_file_to_cache(path))
                        die("Unable to add %s to database", path);
        }
-       if (write_cache(newfd, active_cache, active_nr) || rename(lockfile, indexfile))
+
+       if (!cache_changed)
+               unlink(lockfile);
+       else if (write_cache(newfd, active_cache, active_nr) ||
+                rename(lockfile, indexfile))
                die("Unable to write new cachefile");
 
        lockfile_name = NULL;
-       return has_errors;
+       return has_errors ? 1 : 0;
 }