refs: speed up is_refname_available
[git] / builtin / check-ref-format.c
1 /*
2  * GIT - The information manager from hell
3  */
4
5 #include "cache.h"
6 #include "refs.h"
7 #include "builtin.h"
8 #include "strbuf.h"
9
10 static const char builtin_check_ref_format_usage[] =
11 "git check-ref-format [--normalize] [options] <refname>\n"
12 "   or: git check-ref-format --branch <branchname-shorthand>";
13
14 /*
15  * Return a copy of refname but with leading slashes removed and runs
16  * of adjacent slashes replaced with single slashes.
17  *
18  * This function is similar to normalize_path_copy(), but stripped down
19  * to meet check_ref_format's simpler needs.
20  */
21 static char *collapse_slashes(const char *refname)
22 {
23         char *ret = xmalloc(strlen(refname) + 1);
24         char ch;
25         char prev = '/';
26         char *cp = ret;
27
28         while ((ch = *refname++) != '\0') {
29                 if (prev == '/' && ch == prev)
30                         continue;
31
32                 *cp++ = ch;
33                 prev = ch;
34         }
35         *cp = '\0';
36         return ret;
37 }
38
39 static int check_ref_format_branch(const char *arg)
40 {
41         struct strbuf sb = STRBUF_INIT;
42         int nongit;
43
44         setup_git_directory_gently(&nongit);
45         if (strbuf_check_branch_ref(&sb, arg))
46                 die("'%s' is not a valid branch name", arg);
47         printf("%s\n", sb.buf + 11);
48         return 0;
49 }
50
51 int cmd_check_ref_format(int argc, const char **argv, const char *prefix)
52 {
53         int i;
54         int normalize = 0;
55         int flags = 0;
56         const char *refname;
57
58         if (argc == 2 && !strcmp(argv[1], "-h"))
59                 usage(builtin_check_ref_format_usage);
60
61         if (argc == 3 && !strcmp(argv[1], "--branch"))
62                 return check_ref_format_branch(argv[2]);
63
64         for (i = 1; i < argc && argv[i][0] == '-'; i++) {
65                 if (!strcmp(argv[i], "--normalize") || !strcmp(argv[i], "--print"))
66                         normalize = 1;
67                 else if (!strcmp(argv[i], "--allow-onelevel"))
68                         flags |= REFNAME_ALLOW_ONELEVEL;
69                 else if (!strcmp(argv[i], "--no-allow-onelevel"))
70                         flags &= ~REFNAME_ALLOW_ONELEVEL;
71                 else if (!strcmp(argv[i], "--refspec-pattern"))
72                         flags |= REFNAME_REFSPEC_PATTERN;
73                 else
74                         usage(builtin_check_ref_format_usage);
75         }
76         if (! (i == argc - 1))
77                 usage(builtin_check_ref_format_usage);
78
79         refname = argv[i];
80         if (normalize)
81                 refname = collapse_slashes(refname);
82         if (check_refname_format(refname, flags))
83                 return 1;
84         if (normalize)
85                 printf("%s\n", refname);
86
87         return 0;
88 }