Documentation: improve description of "git reset --keep"
[git/ericb.git] / builtin-show-ref.c
blob17ada88dfb9543ba782b84507b451fabfec28e10
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"
9 static const char * const show_ref_usage[] = {
10 "git show-ref [-q|--quiet] [--verify] [--head] [-d|--dereference] [-s|--hash[=<n>]] [--abbrev[=<n>]] [--tags] [--heads] [--] [pattern*] ",
11 "git show-ref --exclude-existing[=pattern] < ref-list",
12 NULL
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;
20 static void show_one(const char *refname, const unsigned char *sha1)
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);
29 static int show_ref(const char *refname, const unsigned char *sha1, int flag, void *cbdata)
31 struct object *obj;
32 const char *hex;
33 unsigned char peeled[20];
35 if (tags_only || heads_only) {
36 int match;
38 match = heads_only && !prefixcmp(refname, "refs/heads/");
39 match |= tags_only && !prefixcmp(refname, "refs/tags/");
40 if (!match)
41 return 0;
43 if (pattern) {
44 int reflen = strlen(refname);
45 const char **p = pattern, *m;
46 while ((m = *p++) != NULL) {
47 int len = strlen(m);
48 if (len > reflen)
49 continue;
50 if (memcmp(m, refname + reflen - len, len))
51 continue;
52 if (len == reflen)
53 goto match;
54 /* "--verify" requires an exact match */
55 if (verify)
56 continue;
57 if (refname[reflen - len - 1] == '/')
58 goto match;
60 return 0;
63 match:
64 found_match++;
66 /* This changes the semantics slightly that even under quiet we
67 * detect and return error if the repository is corrupt and
68 * ref points at a nonexistent object.
70 if (!has_sha1_file(sha1))
71 die("git show-ref: bad ref %s (%s)", refname,
72 sha1_to_hex(sha1));
74 if (quiet)
75 return 0;
77 show_one(refname, sha1);
79 if (!deref_tags)
80 return 0;
82 if ((flag & REF_ISPACKED) && !peel_ref(refname, peeled)) {
83 if (!is_null_sha1(peeled)) {
84 hex = find_unique_abbrev(peeled, abbrev);
85 printf("%s %s^{}\n", hex, refname);
88 else {
89 obj = parse_object(sha1);
90 if (!obj)
91 die("git show-ref: bad ref %s (%s)", refname,
92 sha1_to_hex(sha1));
93 if (obj->type == OBJ_TAG) {
94 obj = deref_tag(obj, refname, 0);
95 if (!obj)
96 die("git show-ref: bad tag at ref %s (%s)", refname,
97 sha1_to_hex(sha1));
98 hex = find_unique_abbrev(obj->sha1, abbrev);
99 printf("%s %s^{}\n", hex, refname);
102 return 0;
105 static int add_existing(const char *refname, const unsigned char *sha1, int flag, void *cbdata)
107 struct string_list *list = (struct string_list *)cbdata;
108 string_list_insert(refname, list);
109 return 0;
113 * read "^(?:<anything>\s)?<refname>(?:\^\{\})?$" from the standard input,
114 * and
115 * (1) strip "^{}" at the end of line if any;
116 * (2) ignore if match is provided and does not head-match refname;
117 * (3) warn if refname is not a well-formed refname and skip;
118 * (4) ignore if refname is a ref that exists in the local repository;
119 * (5) otherwise output the line.
121 static int exclude_existing(const char *match)
123 static struct string_list existing_refs = { NULL, 0, 0, 0 };
124 char buf[1024];
125 int matchlen = match ? strlen(match) : 0;
127 for_each_ref(add_existing, &existing_refs);
128 while (fgets(buf, sizeof(buf), stdin)) {
129 char *ref;
130 int len = strlen(buf);
132 if (len > 0 && buf[len - 1] == '\n')
133 buf[--len] = '\0';
134 if (3 <= len && !strcmp(buf + len - 3, "^{}")) {
135 len -= 3;
136 buf[len] = '\0';
138 for (ref = buf + len; buf < ref; ref--)
139 if (isspace(ref[-1]))
140 break;
141 if (match) {
142 int reflen = buf + len - ref;
143 if (reflen < matchlen)
144 continue;
145 if (strncmp(ref, match, matchlen))
146 continue;
148 if (check_ref_format(ref)) {
149 warning("ref '%s' ignored", ref);
150 continue;
152 if (!string_list_has_string(&existing_refs, ref)) {
153 printf("%s\n", buf);
156 return 0;
159 static int hash_callback(const struct option *opt, const char *arg, int unset)
161 hash_only = 1;
162 /* Use full length SHA1 if no argument */
163 if (!arg)
164 return 0;
165 return parse_opt_abbrev_cb(opt, arg, unset);
168 static int exclude_existing_callback(const struct option *opt, const char *arg,
169 int unset)
171 exclude_arg = 1;
172 *(const char **)opt->value = arg;
173 return 0;
176 static int help_callback(const struct option *opt, const char *arg, int unset)
178 return -1;
181 static const struct option show_ref_options[] = {
182 OPT_BOOLEAN(0, "tags", &tags_only, "only show tags (can be combined with heads)"),
183 OPT_BOOLEAN(0, "heads", &heads_only, "only show heads (can be combined with tags)"),
184 OPT_BOOLEAN(0, "verify", &verify, "stricter reference checking, "
185 "requires exact ref path"),
186 { OPTION_BOOLEAN, 'h', NULL, &show_head, NULL,
187 "show the HEAD reference",
188 PARSE_OPT_NOARG | PARSE_OPT_HIDDEN },
189 OPT_BOOLEAN(0, "head", &show_head, "show the HEAD reference"),
190 OPT_BOOLEAN('d', "dereference", &deref_tags,
191 "dereference tags into object IDs"),
192 { OPTION_CALLBACK, 's', "hash", &abbrev, "n",
193 "only show SHA1 hash using <n> digits",
194 PARSE_OPT_OPTARG, &hash_callback },
195 OPT__ABBREV(&abbrev),
196 OPT__QUIET(&quiet),
197 { OPTION_CALLBACK, 0, "exclude-existing", &exclude_existing_arg,
198 "pattern", "show refs from stdin that aren't in local repository",
199 PARSE_OPT_OPTARG | PARSE_OPT_NONEG, exclude_existing_callback },
200 { OPTION_CALLBACK, 0, "help-all", NULL, NULL, "show usage",
201 PARSE_OPT_HIDDEN | PARSE_OPT_NOARG, help_callback },
202 OPT_END()
205 int cmd_show_ref(int argc, const char **argv, const char *prefix)
207 if (argc == 2 && !strcmp(argv[1], "-h"))
208 usage_with_options(show_ref_usage, show_ref_options);
210 argc = parse_options(argc, argv, prefix, show_ref_options,
211 show_ref_usage, PARSE_OPT_NO_INTERNAL_HELP);
213 if (exclude_arg)
214 return exclude_existing(exclude_existing_arg);
216 pattern = argv;
217 if (!*pattern)
218 pattern = NULL;
220 if (verify) {
221 if (!pattern)
222 die("--verify requires a reference");
223 while (*pattern) {
224 unsigned char sha1[20];
226 if (!prefixcmp(*pattern, "refs/") &&
227 resolve_ref(*pattern, sha1, 1, NULL)) {
228 if (!quiet)
229 show_one(*pattern, sha1);
231 else if (!quiet)
232 die("'%s' - not a valid ref", *pattern);
233 else
234 return 1;
235 pattern++;
237 return 0;
240 if (show_head)
241 head_ref(show_ref, NULL);
242 for_each_ref(show_ref, NULL);
243 if (!found_match) {
244 if (verify && !quiet)
245 die("No match");
246 return 1;
248 return 0;