1#include "cache.h"
2#include "refs.h"
3#include "builtin.h"
4
5static const char git_update_ref_usage[] =
6"git-update-ref [-m <reason>] (-d <refname> <value> | [--no-deref] <refname> <value> [<oldval>])";
7
8int cmd_update_ref(int argc, const char **argv, const char *prefix)
9{
10 const char *refname=NULL, *value=NULL, *oldval=NULL, *msg=NULL;
11 struct ref_lock *lock;
12 unsigned char sha1[20], oldsha1[20];
13 int i, delete, ref_flags;
14
15 delete = 0;
16 ref_flags = 0;
17 git_config(git_default_config);
18
19 for (i = 1; i < argc; i++) {
20 if (!strcmp("-m", argv[i])) {
21 if (i+1 >= argc)
22 usage(git_update_ref_usage);
23 msg = argv[++i];
24 if (!*msg)
25 die("Refusing to perform update with empty message.");
26 if (strchr(msg, '\n'))
27 die("Refusing to perform update with \\n in message.");
28 continue;
29 }
30 if (!strcmp("-d", argv[i])) {
31 delete = 1;
32 continue;
33 }
34 if (!strcmp("--no-deref", argv[i])) {
35 ref_flags |= REF_NODEREF;
36 continue;
37 }
38 if (!refname) {
39 refname = argv[i];
40 continue;
41 }
42 if (!value) {
43 value = argv[i];
44 continue;
45 }
46 if (!oldval) {
47 oldval = argv[i];
48 continue;
49 }
50 }
51 if (!refname || !value)
52 usage(git_update_ref_usage);
53
54 if (get_sha1(value, sha1))
55 die("%s: not a valid SHA1", value);
56
57 if (delete) {
58 if (oldval)
59 usage(git_update_ref_usage);
60 return delete_ref(refname, sha1);
61 }
62
63 hashclr(oldsha1);
64 if (oldval && *oldval && get_sha1(oldval, oldsha1))
65 die("%s: not a valid old SHA1", oldval);
66
67 lock = lock_any_ref_for_update(refname, oldval ? oldsha1 : NULL, ref_flags);
68 if (!lock)
69 die("%s: cannot lock the ref", refname);
70 if (write_ref_sha1(lock, sha1, msg) < 0)
71 die("%s: cannot update the ref", refname);
72 return 0;
73}