Stick a comment to update-cache.c:refresh_cache() that you can't
[git.git] / update-cache.c
index 16e1bb9..19d8f82 100644 (file)
@@ -13,7 +13,7 @@
  * like "update-cache *" and suddenly having all the object
  * files be revision controlled.
  */
-static int allow_add = 0, allow_remove = 0, not_new = 0;
+static int allow_add = 0, allow_remove = 0, allow_replace = 0, not_new = 0;
 
 /* Three functions to allow overloaded pointer return; see linux/err.h */
 static inline void *ERR_PTR(long error)
@@ -31,57 +31,6 @@ static inline long IS_ERR(const void *ptr)
        return (unsigned long)ptr > (unsigned long)-1000L;
 }
 
-static int index_fd(unsigned char *sha1, int fd, struct stat *st)
-{
-       z_stream stream;
-       unsigned long size = st->st_size;
-       int max_out_bytes = size + 200;
-       void *out = xmalloc(max_out_bytes);
-       void *metadata = xmalloc(200);
-       int metadata_size;
-       void *in;
-       SHA_CTX c;
-
-       in = "";
-       if (size)
-               in = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
-       close(fd);
-       if (!out || (int)(long)in == -1)
-               return -1;
-
-       metadata_size = 1+sprintf(metadata, "blob %lu", size);
-
-       SHA1_Init(&c);
-       SHA1_Update(&c, metadata, metadata_size);
-       SHA1_Update(&c, in, size);
-       SHA1_Final(sha1, &c);
-
-       memset(&stream, 0, sizeof(stream));
-       deflateInit(&stream, Z_BEST_COMPRESSION);
-
-       /*
-        * ASCII size + nul byte
-        */     
-       stream.next_in = metadata;
-       stream.avail_in = metadata_size;
-       stream.next_out = out;
-       stream.avail_out = max_out_bytes;
-       while (deflate(&stream, 0) == Z_OK)
-               /* nothing */;
-
-       /*
-        * File content
-        */
-       stream.next_in = in;
-       stream.avail_in = size;
-       while (deflate(&stream, Z_FINISH) == Z_OK)
-               /*nothing */;
-
-       deflateEnd(&stream);
-       
-       return write_sha1_buffer(sha1, out, stream.total_out);
-}
-
 /*
  * This only updates the "non-critical" parts of the directory
  * cache, ie the parts that aren't tracked by GIT, and only used
@@ -104,22 +53,27 @@ static void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
 
 static int add_file_to_cache(char *path)
 {
-       int size, namelen;
+       int size, namelen, option, status;
        struct cache_entry *ce;
        struct stat st;
        int fd;
-
-       fd = open(path, O_RDONLY);
-       if (fd < 0) {
-               if (errno == ENOENT) {
+       char *target;
+
+       status = lstat(path, &st);
+       if (status < 0 || S_ISDIR(st.st_mode)) {
+               /* When we used to have "path" and now we want to add
+                * "path/file", we need a way to remove "path" before
+                * being able to add "path/file".  However,
+                * "git-update-cache --remove path" would not work.
+                * --force-remove can be used but this is more user
+                * friendly, especially since we can do the opposite
+                * case just fine without --force-remove.
+                */
+               if (status == 0 || (errno == ENOENT || errno == ENOTDIR)) {
                        if (allow_remove)
                                return remove_file_from_cache(path);
                }
-               return -1;
-       }
-       if (fstat(fd, &st) < 0) {
-               close(fd);
-               return -1;
+               return error("open(\"%s\"): %s", path, strerror(errno));
        }
        namelen = strlen(path);
        size = cache_entry_size(namelen);
@@ -129,11 +83,30 @@ 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:
+               target = xmalloc(st.st_size+1);
+               if (readlink(path, target, st.st_size+1) != st.st_size) {
+                       free(target);
+                       return -1;
+               }
+               if (write_sha1_file(target, st.st_size, "blob", ce->sha1))
+                       return -1;
+               free(target);
+               break;
+       default:
                return -1;
-
-       return add_cache_entry(ce, allow_add);
+       }
+       option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
+       option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
+       return add_cache_entry(ce, option);
 }
 
 static int match_data(int fd, void *buffer, unsigned long size)
@@ -158,7 +131,7 @@ static int compare_data(struct cache_entry *ce, unsigned long expected_size)
        if (fd >= 0) {
                void *buffer;
                unsigned long size;
-               char type[10];
+               char type[20];
 
                buffer = read_sha1_file(ce->sha1, type, &size);
                if (buffer) {
@@ -171,6 +144,33 @@ static int compare_data(struct cache_entry *ce, unsigned long expected_size)
        return match;
 }
 
+static int compare_link(struct cache_entry *ce, unsigned long expected_size)
+{
+       int match = -1;
+       char *target;
+       void *buffer;
+       unsigned long size;
+       char type[10];
+       int len;
+
+       target = xmalloc(expected_size);
+       len = readlink(ce->name, target, expected_size);
+       if (len != expected_size) {
+               free(target);
+               return -1;
+       }
+       buffer = read_sha1_file(ce->sha1, type, &size);
+       if (!buffer) {
+               free(target);
+               return -1;
+       }
+       if (size == expected_size)
+               match = memcmp(buffer, target, size);
+       free(buffer);
+       free(target);
+       return match;
+}
+
 /*
  * "refresh" does not calculate a new sha1 file or bring the
  * cache up-to-date for mode/content changes. But what it
@@ -188,7 +188,7 @@ 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);
@@ -196,14 +196,24 @@ 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))
+       switch (st.st_mode & S_IFMT) {
+       case S_IFREG:
+               if (compare_data(ce, st.st_size))
+                       return ERR_PTR(-EINVAL);
+               break;
+       case S_IFLNK:
+               if (compare_link(ce, st.st_size))
+                       return ERR_PTR(-EINVAL);
+               break;
+       default:
                return ERR_PTR(-EINVAL);
+       }
 
        size = ce_size(ce);
        updated = xmalloc(size);
@@ -212,15 +222,17 @@ static struct cache_entry *refresh_entry(struct cache_entry *ce)
        return updated;
 }
 
-static void refresh_cache(void)
+static int refresh_cache(void)
 {
        int i;
+       int has_errors = 0;
 
        for (i = 0; i < active_nr; i++) {
                struct cache_entry *ce, *new;
                ce = active_cache[i];
                if (ce_stage(ce)) {
                        printf("%s: needs merge\n", ce->name);
+                       has_errors = 1;
                        while ((i < active_nr) &&
                               ! strcmp(active_cache[i]->name, ce->name))
                                i++;
@@ -230,12 +242,19 @@ static void refresh_cache(void)
 
                new = refresh_entry(ce);
                if (IS_ERR(new)) {
-                       if (!(not_new && PTR_ERR(new) == -ENOENT))
+                       if (!(not_new && PTR_ERR(new) == -ENOENT)) {
                                printf("%s: needs update\n", ce->name);
+                               has_errors = 1;
+                       }
                        continue;
                }
+               active_cache_changed = 1;
+               /* You can NOT just free active_cache[i] here, since it
+                * might not be necessarily malloc()ed but can also come
+                * from mmap(). */
                active_cache[i] = new;
        }
+       return has_errors;
 }
 
 /*
@@ -268,7 +287,7 @@ inside:
 
 static int add_cacheinfo(char *arg1, char *arg2, char *arg3)
 {
-       int size, len;
+       int size, len, option;
        unsigned int mode;
        unsigned char sha1[20];
        struct cache_entry *ce;
@@ -289,7 +308,9 @@ static int add_cacheinfo(char *arg1, char *arg2, char *arg3)
        memcpy(ce->name, arg3, len);
        ce->ce_flags = htons(len);
        ce->ce_mode = create_ce_mode(mode);
-       return add_cache_entry(ce, allow_add);
+       option = allow_add ? ADD_CACHE_OK_TO_ADD : 0;
+       option |= allow_replace ? ADD_CACHE_OK_TO_REPLACE : 0;
+       return add_cache_entry(ce, option);
 }
 
 static const char *lockfile_name = NULL;
@@ -307,7 +328,7 @@ static void remove_lock_file_on_signal(int signo)
 
 int main(int argc, char **argv)
 {
-       int i, newfd, entries;
+       int i, newfd, entries, has_errors = 0;
        int allow_options = 1;
        static char lockfile[MAXPATHLEN+1];
        const char *indexfile = get_index_file();
@@ -338,20 +359,35 @@ int main(int argc, char **argv)
                                allow_add = 1;
                                continue;
                        }
+                       if (!strcmp(path, "--replace")) {
+                               allow_replace = 1;
+                               continue;
+                       }
                        if (!strcmp(path, "--remove")) {
                                allow_remove = 1;
                                continue;
                        }
                        if (!strcmp(path, "--refresh")) {
-                               refresh_cache();
+                               has_errors |= refresh_cache();
                                continue;
                        }
                        if (!strcmp(path, "--cacheinfo")) {
-                               if (i+3 >= argc || add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
+                               if (i+3 >= argc)
                                        die("update-cache: --cacheinfo <mode> <sha1> <path>");
+                               if (add_cacheinfo(argv[i+1], argv[i+2], argv[i+3]))
+                                       die("update-cache: --cacheinfo cannot add %s", argv[i+3]);
                                i += 3;
                                continue;
                        }
+                       if (!strcmp(path, "--force-remove")) {
+                               if (argc <= i + 1)
+                                       die("update-cache: --force-remove <path>");
+                               if (remove_file_from_cache(argv[i+1]))
+                                       die("update-cache: --force-remove cannot remove %s", argv[i+1]);
+                               i++;
+                               continue;
+                       }
+
                        if (!strcmp(path, "--ignore-missing")) {
                                not_new = 1;
                                continue;
@@ -369,5 +405,5 @@ int main(int argc, char **argv)
                die("Unable to write new cachefile");
 
        lockfile_name = NULL;
-       return 0;
+       return has_errors ? 1 : 0;
 }