grab_single_ref(): rewrite to take an object_id argument
[git] / builtin / show-ref.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "refs.h"
4 #include "object.h"
5 #include "tag.h"
6 #include "string-list.h"
7 #include "parse-options.h"
8
9 static const char * const show_ref_usage[] = {
10         N_("git show-ref [-q | --quiet] [--verify] [--head] [-d | --dereference] [-s | --hash[=<n>]] [--abbrev[=<n>]] [--tags] [--heads] [--] [<pattern>...]"),
11         N_("git show-ref --exclude-existing[=pattern] < ref-list"),
12         NULL
13 };
14
15 static int deref_tags, show_head, tags_only, heads_only, found_match, verify,
16            quiet, hash_only, abbrev, exclude_arg;
17 static const char **pattern;
18 static const char *exclude_existing_arg;
19
20 static void show_one(const char *refname, const unsigned char *sha1)
21 {
22         const char *hex = find_unique_abbrev(sha1, abbrev);
23         if (hash_only)
24                 printf("%s\n", hex);
25         else
26                 printf("%s %s\n", hex, refname);
27 }
28
29 static int show_ref(const char *refname, const unsigned char *sha1, int flag, void *cbdata)
30 {
31         const char *hex;
32         unsigned char peeled[20];
33
34         if (show_head && !strcmp(refname, "HEAD"))
35                 goto match;
36
37         if (tags_only || heads_only) {
38                 int match;
39
40                 match = heads_only && starts_with(refname, "refs/heads/");
41                 match |= tags_only && starts_with(refname, "refs/tags/");
42                 if (!match)
43                         return 0;
44         }
45         if (pattern) {
46                 int reflen = strlen(refname);
47                 const char **p = pattern, *m;
48                 while ((m = *p++) != NULL) {
49                         int len = strlen(m);
50                         if (len > reflen)
51                                 continue;
52                         if (memcmp(m, refname + reflen - len, len))
53                                 continue;
54                         if (len == reflen)
55                                 goto match;
56                         /* "--verify" requires an exact match */
57                         if (verify)
58                                 continue;
59                         if (refname[reflen - len - 1] == '/')
60                                 goto match;
61                 }
62                 return 0;
63         }
64
65 match:
66         found_match++;
67
68         /* This changes the semantics slightly that even under quiet we
69          * detect and return error if the repository is corrupt and
70          * ref points at a nonexistent object.
71          */
72         if (!has_sha1_file(sha1))
73                 die("git show-ref: bad ref %s (%s)", refname,
74                     sha1_to_hex(sha1));
75
76         if (quiet)
77                 return 0;
78
79         show_one(refname, sha1);
80
81         if (!deref_tags)
82                 return 0;
83
84         if (!peel_ref(refname, peeled)) {
85                 hex = find_unique_abbrev(peeled, abbrev);
86                 printf("%s %s^{}\n", hex, refname);
87         }
88         return 0;
89 }
90
91 static int add_existing(const char *refname, const unsigned char *sha1, int flag, void *cbdata)
92 {
93         struct string_list *list = (struct string_list *)cbdata;
94         string_list_insert(list, refname);
95         return 0;
96 }
97
98 /*
99  * read "^(?:<anything>\s)?<refname>(?:\^\{\})?$" from the standard input,
100  * and
101  * (1) strip "^{}" at the end of line if any;
102  * (2) ignore if match is provided and does not head-match refname;
103  * (3) warn if refname is not a well-formed refname and skip;
104  * (4) ignore if refname is a ref that exists in the local repository;
105  * (5) otherwise output the line.
106  */
107 static int exclude_existing(const char *match)
108 {
109         static struct string_list existing_refs = STRING_LIST_INIT_DUP;
110         char buf[1024];
111         int matchlen = match ? strlen(match) : 0;
112         struct each_ref_fn_sha1_adapter wrapped_add_existing =
113                 {add_existing, &existing_refs};
114
115         for_each_ref(each_ref_fn_adapter, &wrapped_add_existing);
116         while (fgets(buf, sizeof(buf), stdin)) {
117                 char *ref;
118                 int len = strlen(buf);
119
120                 if (len > 0 && buf[len - 1] == '\n')
121                         buf[--len] = '\0';
122                 if (3 <= len && !strcmp(buf + len - 3, "^{}")) {
123                         len -= 3;
124                         buf[len] = '\0';
125                 }
126                 for (ref = buf + len; buf < ref; ref--)
127                         if (isspace(ref[-1]))
128                                 break;
129                 if (match) {
130                         int reflen = buf + len - ref;
131                         if (reflen < matchlen)
132                                 continue;
133                         if (strncmp(ref, match, matchlen))
134                                 continue;
135                 }
136                 if (check_refname_format(ref, 0)) {
137                         warning("ref '%s' ignored", ref);
138                         continue;
139                 }
140                 if (!string_list_has_string(&existing_refs, ref)) {
141                         printf("%s\n", buf);
142                 }
143         }
144         return 0;
145 }
146
147 static int hash_callback(const struct option *opt, const char *arg, int unset)
148 {
149         hash_only = 1;
150         /* Use full length SHA1 if no argument */
151         if (!arg)
152                 return 0;
153         return parse_opt_abbrev_cb(opt, arg, unset);
154 }
155
156 static int exclude_existing_callback(const struct option *opt, const char *arg,
157                                      int unset)
158 {
159         exclude_arg = 1;
160         *(const char **)opt->value = arg;
161         return 0;
162 }
163
164 static int help_callback(const struct option *opt, const char *arg, int unset)
165 {
166         return -1;
167 }
168
169 static const struct option show_ref_options[] = {
170         OPT_BOOL(0, "tags", &tags_only, N_("only show tags (can be combined with heads)")),
171         OPT_BOOL(0, "heads", &heads_only, N_("only show heads (can be combined with tags)")),
172         OPT_BOOL(0, "verify", &verify, N_("stricter reference checking, "
173                     "requires exact ref path")),
174         OPT_HIDDEN_BOOL('h', NULL, &show_head,
175                         N_("show the HEAD reference, even if it would be filtered out")),
176         OPT_BOOL(0, "head", &show_head,
177           N_("show the HEAD reference, even if it would be filtered out")),
178         OPT_BOOL('d', "dereference", &deref_tags,
179                     N_("dereference tags into object IDs")),
180         { OPTION_CALLBACK, 's', "hash", &abbrev, N_("n"),
181           N_("only show SHA1 hash using <n> digits"),
182           PARSE_OPT_OPTARG, &hash_callback },
183         OPT__ABBREV(&abbrev),
184         OPT__QUIET(&quiet,
185                    N_("do not print results to stdout (useful with --verify)")),
186         { OPTION_CALLBACK, 0, "exclude-existing", &exclude_existing_arg,
187           N_("pattern"), N_("show refs from stdin that aren't in local repository"),
188           PARSE_OPT_OPTARG | PARSE_OPT_NONEG, exclude_existing_callback },
189         { OPTION_CALLBACK, 0, "help-all", NULL, NULL, N_("show usage"),
190           PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
191         OPT_END()
192 };
193
194 int cmd_show_ref(int argc, const char **argv, const char *prefix)
195 {
196         struct each_ref_fn_sha1_adapter wrapped_show_ref =
197                 {show_ref, NULL};
198
199         if (argc == 2 && !strcmp(argv[1], "-h"))
200                 usage_with_options(show_ref_usage, show_ref_options);
201
202         argc = parse_options(argc, argv, prefix, show_ref_options,
203                              show_ref_usage, PARSE_OPT_NO_INTERNAL_HELP);
204
205         if (exclude_arg)
206                 return exclude_existing(exclude_existing_arg);
207
208         pattern = argv;
209         if (!*pattern)
210                 pattern = NULL;
211
212         if (verify) {
213                 if (!pattern)
214                         die("--verify requires a reference");
215                 while (*pattern) {
216                         unsigned char sha1[20];
217
218                         if (starts_with(*pattern, "refs/") &&
219                             !read_ref(*pattern, sha1)) {
220                                 if (!quiet)
221                                         show_one(*pattern, sha1);
222                         }
223                         else if (!quiet)
224                                 die("'%s' - not a valid ref", *pattern);
225                         else
226                                 return 1;
227                         pattern++;
228                 }
229                 return 0;
230         }
231
232         if (show_head)
233                 head_ref(each_ref_fn_adapter, &wrapped_show_ref);
234         for_each_ref(each_ref_fn_adapter, &wrapped_show_ref);
235         if (!found_match) {
236                 if (verify && !quiet)
237                         die("No match");
238                 return 1;
239         }
240         return 0;
241 }