Merge branch 'sb/merge-friendly'
[gitweb.git] / refs.c
diff --git a/refs.c b/refs.c
index 96ea8b6907b1e4be9c7b8575ff7e4a36f5a7a5f8..a101ff3bf88dafa56ac85fcd977c0ae6be1b495e 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -1,10 +1,8 @@
-#include "refs.h"
 #include "cache.h"
+#include "refs.h"
 #include "object.h"
 #include "tag.h"
 
-#include <errno.h>
-
 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
 #define REF_KNOWS_PEELED 04
 
@@ -534,7 +532,7 @@ int check_ref_format(const char *ref)
                level++;
                if (!ch) {
                        if (level < 2)
-                               return -1; /* at least of form "heads/blah" */
+                               return -2; /* at least of form "heads/blah" */
                        return 0;
                }
        }
@@ -610,6 +608,29 @@ static int remove_empty_directories(char *file)
        return remove_empty_dir_recursive(path, len);
 }
 
+static int is_refname_available(const char *ref, const char *oldref,
+                               struct ref_list *list, int quiet)
+{
+       int namlen = strlen(ref); /* e.g. 'foo/bar' */
+       while (list) {
+               /* list->name could be 'foo' or 'foo/bar/baz' */
+               if (!oldref || strcmp(oldref, list->name)) {
+                       int len = strlen(list->name);
+                       int cmplen = (namlen < len) ? namlen : len;
+                       const char *lead = (namlen < len) ? list->name : ref;
+                       if (!strncmp(ref, list->name, cmplen) &&
+                           lead[cmplen] == '/') {
+                               if (!quiet)
+                                       error("'%s' exists; cannot create '%s'",
+                                             list->name, ref);
+                               return 0;
+                       }
+               }
+               list = list->next;
+       }
+       return 1;
+}
+
 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int *flag)
 {
        char *ref_file;
@@ -643,29 +664,14 @@ static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char
                        orig_ref, strerror(errno));
                goto error_return;
        }
-       if (is_null_sha1(lock->old_sha1)) {
-               /* The ref did not exist and we are creating it.
-                * Make sure there is no existing ref that is packed
-                * whose name begins with our refname, nor a ref whose
-                * name is a proper prefix of our refname.
-                */
-               int namlen = strlen(ref); /* e.g. 'foo/bar' */
-               struct ref_list *list = get_packed_refs();
-               while (list) {
-                       /* list->name could be 'foo' or 'foo/bar/baz' */
-                       int len = strlen(list->name);
-                       int cmplen = (namlen < len) ? namlen : len;
-                       const char *lead = (namlen < len) ? list->name : ref;
-
-                       if (!strncmp(ref, list->name, cmplen) &&
-                           lead[cmplen] == '/') {
-                               error("'%s' exists; cannot create '%s'",
-                                     list->name, ref);
-                               goto error_return;
-                       }
-                       list = list->next;
-               }
-       }
+       /* When the ref did not exist and we are creating it,
+        * make sure there is no existing ref that is packed
+        * whose name begins with our refname, nor a ref whose
+        * name is a proper prefix of our refname.
+        */
+       if (is_null_sha1(lock->old_sha1) &&
+            !is_refname_available(ref, NULL, get_packed_refs(), 0))
+               goto error_return;
 
        lock->lk = xcalloc(1, sizeof(struct lock_file));
 
@@ -776,6 +782,127 @@ int delete_ref(const char *refname, unsigned char *sha1)
        return ret;
 }
 
+int rename_ref(const char *oldref, const char *newref, const char *logmsg)
+{
+       static const char renamed_ref[] = "RENAMED-REF";
+       unsigned char sha1[20], orig_sha1[20];
+       int flag = 0, logmoved = 0;
+       struct ref_lock *lock;
+       struct stat loginfo;
+       int log = !lstat(git_path("logs/%s", oldref), &loginfo);
+
+       if (S_ISLNK(loginfo.st_mode))
+               return error("reflog for %s is a symlink", oldref);
+
+       if (!resolve_ref(oldref, orig_sha1, 1, &flag))
+               return error("refname %s not found", oldref);
+
+       if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
+               return 1;
+
+       if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
+               return 1;
+
+       lock = lock_ref_sha1_basic(renamed_ref, NULL, NULL);
+       if (!lock)
+               return error("unable to lock %s", renamed_ref);
+       lock->force_write = 1;
+       if (write_ref_sha1(lock, orig_sha1, logmsg))
+               return error("unable to save current sha1 in %s", renamed_ref);
+
+       if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
+               return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
+                       oldref, strerror(errno));
+
+       if (delete_ref(oldref, orig_sha1)) {
+               error("unable to delete old %s", oldref);
+               goto rollback;
+       }
+
+       if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1)) {
+               if (errno==EISDIR) {
+                       if (remove_empty_directories(git_path("%s", newref))) {
+                               error("Directory not empty: %s", newref);
+                               goto rollback;
+                       }
+               } else {
+                       error("unable to delete existing %s", newref);
+                       goto rollback;
+               }
+       }
+
+       if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
+               error("unable to create directory for %s", newref);
+               goto rollback;
+       }
+
+ retry:
+       if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
+               if (errno==EISDIR) {
+                       if (remove_empty_directories(git_path("logs/%s", newref))) {
+                               error("Directory not empty: logs/%s", newref);
+                               goto rollback;
+                       }
+                       goto retry;
+               } else {
+                       error("unable to move logfile tmp-renamed-log to logs/%s: %s",
+                               newref, strerror(errno));
+                       goto rollback;
+               }
+       }
+       logmoved = log;
+
+       lock = lock_ref_sha1_basic(newref, NULL, NULL);
+       if (!lock) {
+               error("unable to lock %s for update", newref);
+               goto rollback;
+       }
+
+       lock->force_write = 1;
+       hashcpy(lock->old_sha1, orig_sha1);
+       if (write_ref_sha1(lock, orig_sha1, logmsg)) {
+               error("unable to write current sha1 into %s", newref);
+               goto rollback;
+       }
+
+       if (!strncmp(oldref, "refs/heads/", 11) &&
+                       !strncmp(newref, "refs/heads/", 11)) {
+               char oldsection[1024], newsection[1024];
+
+               snprintf(oldsection, 1024, "branch.%s", oldref + 11);
+               snprintf(newsection, 1024, "branch.%s", newref + 11);
+               if (git_config_rename_section(oldsection, newsection) < 0)
+                       return 1;
+       }
+
+       return 0;
+
+ rollback:
+       lock = lock_ref_sha1_basic(oldref, NULL, NULL);
+       if (!lock) {
+               error("unable to lock %s for rollback", oldref);
+               goto rollbacklog;
+       }
+
+       lock->force_write = 1;
+       flag = log_all_ref_updates;
+       log_all_ref_updates = 0;
+       if (write_ref_sha1(lock, orig_sha1, NULL))
+               error("unable to write current sha1 into %s", oldref);
+       log_all_ref_updates = flag;
+
+ rollbacklog:
+       if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
+               error("unable to restore logfile %s from %s: %s",
+                       oldref, newref, strerror(errno));
+       if (!logmoved && log &&
+           rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
+               error("unable to restore logfile %s from tmp-renamed-log: %s",
+                       oldref, strerror(errno));
+
+       return 1;
+}
+
 void unlock_ref(struct ref_lock *lock)
 {
        if (lock->lock_fd >= 0) {