5ee960bf41c4518b6c5530acb123a7ed668538fc
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> | <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;
14
15 delete = 0;
16 git_config(git_default_config);
17
18 for (i = 1; i < argc; i++) {
19 if (!strcmp("-m", argv[i])) {
20 if (i+1 >= argc)
21 usage(git_update_ref_usage);
22 msg = argv[++i];
23 if (!*msg)
24 die("Refusing to perform update with empty message.");
25 if (strchr(msg, '\n'))
26 die("Refusing to perform update with \\n in message.");
27 continue;
28 }
29 if (!strcmp("-d", argv[i])) {
30 delete = 1;
31 continue;
32 }
33 if (!refname) {
34 refname = argv[i];
35 continue;
36 }
37 if (!value) {
38 value = argv[i];
39 continue;
40 }
41 if (!oldval) {
42 oldval = argv[i];
43 continue;
44 }
45 }
46 if (!refname || !value)
47 usage(git_update_ref_usage);
48
49 if (get_sha1(value, sha1))
50 die("%s: not a valid SHA1", value);
51
52 if (delete) {
53 if (oldval)
54 usage(git_update_ref_usage);
55 return delete_ref(refname, sha1);
56 }
57
58 hashclr(oldsha1);
59 if (oldval && *oldval && get_sha1(oldval, oldsha1))
60 die("%s: not a valid old SHA1", oldval);
61
62 lock = lock_any_ref_for_update(refname, oldval ? oldsha1 : NULL);
63 if (!lock)
64 die("%s: cannot lock the ref", refname);
65 if (write_ref_sha1(lock, sha1, msg) < 0)
66 die("%s: cannot update the ref", refname);
67 return 0;
68}