Teach "git-read-tree -u" to check out submodules as a directory

This actually allows us to check out a supermodule after cloning, although
the submodules themselves will obviously not be checked out, and will just
be empty directories.

Checking out the submodules will be up to higher levels - we may not even
want to!

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/entry.c b/entry.c
index d72f811580ad10e792e38b40fe79bf4af3868846..50ffae40c76478a10d1c3fc9623105e7f14f863e 100644 (file)
--- a/entry.c
+++ b/entry.c
@@ -62,26 +62,33 @@ static int create_file(const char *path, unsigned int mode)
        return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
 }
 
+static void *read_blob_entry(struct cache_entry *ce, const char *path, unsigned long *size)
+{
+       enum object_type type;
+       void *new = read_sha1_file(ce->sha1, &type, size);
+
+       if (new) {
+               if (type == OBJ_BLOB)
+                       return new;
+               free(new);
+       }
+       return NULL;
+}
+
 static int write_entry(struct cache_entry *ce, char *path, struct checkout *state, int to_tempfile)
 {
        int fd;
-       void *new;
-       unsigned long size;
        long wrote;
-       enum object_type type;
 
-       new = read_sha1_file(ce->sha1, &type, &size);
-       if (!new || type != OBJ_BLOB) {
-               if (new)
-                       free(new);
-               return error("git-checkout-index: unable to read sha1 file of %s (%s)",
-                       path, sha1_to_hex(ce->sha1));
-       }
        switch (ntohl(ce->ce_mode) & S_IFMT) {
-               char *buf;
-               unsigned long nsize;
+               char *buf, *new;
+               unsigned long size, nsize;
 
        case S_IFREG:
+               new = read_blob_entry(ce, path, &size);
+               if (!new)
+                       return error("git-checkout-index: unable to read sha1 file of %s (%s)",
+                               path, sha1_to_hex(ce->sha1));
                if (to_tempfile) {
                        strcpy(path, ".merge_file_XXXXXX");
                        fd = mkstemp(path);
@@ -111,6 +118,10 @@ static int write_entry(struct cache_entry *ce, char *path, struct checkout *stat
                        return error("git-checkout-index: unable to write file %s", path);
                break;
        case S_IFLNK:
+               new = read_blob_entry(ce, path, &size);
+               if (!new)
+                       return error("git-checkout-index: unable to read sha1 file of %s (%s)",
+                               path, sha1_to_hex(ce->sha1));
                if (to_tempfile || !has_symlinks) {
                        if (to_tempfile) {
                                strcpy(path, ".merge_link_XXXXXX");
@@ -136,8 +147,13 @@ static int write_entry(struct cache_entry *ce, char *path, struct checkout *stat
                                                 "symlink %s (%s)", path, strerror(errno));
                }
                break;
+       case S_IFDIRLNK:
+               if (to_tempfile)
+                       return error("git-checkout-index: cannot create temporary subproject %s", path);
+               if (mkdir(path, 0777) < 0)
+                       return error("git-checkout-index: cannot create subproject directory %s", path);
+               break;
        default:
-               free(new);
                return error("git-checkout-index: unknown file mode for %s", path);
        }
 
@@ -179,6 +195,9 @@ int checkout_entry(struct cache_entry *ce, struct checkout *state, char *topath)
                 */
                unlink(path);
                if (S_ISDIR(st.st_mode)) {
+                       /* If it is a gitlink, leave it alone! */
+                       if (S_ISDIRLNK(ntohl(ce->ce_mode)))
+                               return 0;
                        if (!state->force)
                                return error("%s is a directory", path);
                        remove_subtree(path);