#include "cache.h"
#include "refs.h"
-#include <ctype.h>
-static const char git_update_ref_usage[] = "git-update-ref <refname> <value> [<oldval>]";
+static const char git_update_ref_usage[] =
+"git-update-ref <refname> <value> [<oldval>] [-m <reason>]";
-#define MAXDEPTH 5
-
-static const char *resolve_ref(const char *path, unsigned char *sha1)
+int main(int argc, char **argv)
{
- int depth = MAXDEPTH, len;
- char buffer[256];
-
- for (;;) {
- struct stat st;
- int fd;
-
- if (--depth < 0)
- return NULL;
+ const char *refname=NULL, *value=NULL, *oldval=NULL, *msg=NULL;
+ struct ref_lock *lock;
+ unsigned char sha1[20], oldsha1[20];
+ int i;
- /* Special case: non-existing file */
- if (lstat(path, &st) < 0) {
- if (errno != ENOENT)
- return NULL;
- memset(sha1, 0, 20);
- return path;
+ setup_git_directory();
+ git_config(git_default_config);
+
+ for (i = 1; i < argc; i++) {
+ if (!strcmp("-m", argv[i])) {
+ if (i+1 >= argc)
+ usage(git_update_ref_usage);
+ msg = argv[++i];
+ if (!*msg)
+ die("Refusing to perform update with empty message.");
+ if (strchr(msg, '\n'))
+ die("Refusing to perform update with \\n in message.");
+ continue;
}
-
- /* Follow "normalized" - ie "refs/.." symlinks by hand */
- if (S_ISLNK(st.st_mode)) {
- len = readlink(path, buffer, sizeof(buffer)-1);
- if (len >= 5 && !memcmp("refs/", buffer, 5)) {
- path = git_path("%.*s", len, buffer);
- continue;
- }
+ if (!refname) {
+ refname = argv[i];
+ continue;
+ }
+ if (!value) {
+ value = argv[i];
+ continue;
+ }
+ if (!oldval) {
+ oldval = argv[i];
+ continue;
}
-
- /*
- * Anything else, just open it and try to use it as
- * a ref
- */
- fd = open(path, O_RDONLY);
- if (fd < 0)
- return NULL;
- len = read(fd, buffer, sizeof(buffer)-1);
- close(fd);
- break;
}
- if (len < 40 || get_sha1_hex(buffer, sha1))
- return NULL;
- return path;
-}
-
-static int re_verify(const char *path, unsigned char *oldsha1, unsigned char *currsha1)
-{
- char buf[40];
- int fd = open(path, O_RDONLY), nr;
- if (fd < 0)
- return -1;
- nr = read(fd, buf, 40);
- close(fd);
- if (nr != 40 || get_sha1_hex(buf, currsha1) < 0)
- return -1;
- return memcmp(oldsha1, currsha1, 20) ? -1 : 0;
-}
-
-int main(int argc, char **argv)
-{
- char *hex;
- const char *refname, *value, *oldval, *path, *lockpath;
- unsigned char sha1[20], oldsha1[20], currsha1[20];
- int fd, written;
-
- setup_git_directory();
- if (argc < 3 || argc > 4)
+ if (!refname || !value)
usage(git_update_ref_usage);
- refname = argv[1];
- value = argv[2];
- oldval = argv[3];
- if (get_sha1(value, sha1) < 0)
+ if (get_sha1(value, sha1))
die("%s: not a valid SHA1", value);
memset(oldsha1, 0, 20);
- if (oldval && get_sha1(oldval, oldsha1) < 0)
+ if (oldval && get_sha1(oldval, oldsha1))
die("%s: not a valid old SHA1", oldval);
- path = resolve_ref(git_path("%s", refname), currsha1);
- if (!path)
- die("No such ref: %s", refname);
-
- if (oldval) {
- if (memcmp(currsha1, oldsha1, 20))
- die("Ref %s changed to %s", refname, sha1_to_hex(currsha1));
- /* Nothing to do? */
- if (!memcmp(oldsha1, sha1, 20))
- exit(0);
- }
- path = strdup(path);
- lockpath = mkpath("%s.lock", path);
-
- fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
- if (fd < 0)
- die("Unable to create %s", lockpath);
- hex = sha1_to_hex(sha1);
- hex[40] = '\n';
- written = write(fd, hex, 41);
- close(fd);
- if (written != 41) {
- unlink(lockpath);
- die("Unable to write to %s", lockpath);
- }
-
- /*
- * Re-read the ref after getting the lock to verify
- */
- if (oldval && re_verify(path, oldsha1, currsha1) < 0) {
- unlink(lockpath);
- die("Ref lock failed");
- }
-
- /*
- * Finally, replace the old ref with the new one
- */
- if (rename(lockpath, path) < 0) {
- unlink(lockpath);
- die("Unable to create %s", path);
- }
+ lock = lock_any_ref_for_update(refname, oldval ? oldsha1 : NULL, 0);
+ if (!lock)
+ return 1;
+ if (write_ref_sha1(lock, sha1, msg) < 0)
+ return 1;
return 0;
}