Detached HEAD (experimental)
[git] / builtin-name-rev.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "commit.h"
4 #include "tag.h"
5 #include "refs.h"
6
7 static const char name_rev_usage[] =
8         "git-name-rev [--tags] ( --all | --stdin | committish [committish...] )\n";
9
10 typedef struct rev_name {
11         const char *tip_name;
12         int merge_traversals;
13         int generation;
14 } rev_name;
15
16 static long cutoff = LONG_MAX;
17
18 static void name_rev(struct commit *commit,
19                 const char *tip_name, int merge_traversals, int generation,
20                 int deref)
21 {
22         struct rev_name *name = (struct rev_name *)commit->util;
23         struct commit_list *parents;
24         int parent_number = 1;
25
26         if (!commit->object.parsed)
27                 parse_commit(commit);
28
29         if (commit->date < cutoff)
30                 return;
31
32         if (deref) {
33                 char *new_name = xmalloc(strlen(tip_name)+3);
34                 strcpy(new_name, tip_name);
35                 strcat(new_name, "^0");
36                 tip_name = new_name;
37
38                 if (generation)
39                         die("generation: %d, but deref?", generation);
40         }
41
42         if (name == NULL) {
43                 name = xmalloc(sizeof(rev_name));
44                 commit->util = name;
45                 goto copy_data;
46         } else if (name->merge_traversals > merge_traversals ||
47                         (name->merge_traversals == merge_traversals &&
48                          name->generation > generation)) {
49 copy_data:
50                 name->tip_name = tip_name;
51                 name->merge_traversals = merge_traversals;
52                 name->generation = generation;
53         } else
54                 return;
55
56         for (parents = commit->parents;
57                         parents;
58                         parents = parents->next, parent_number++) {
59                 if (parent_number > 1) {
60                         char *new_name = xmalloc(strlen(tip_name)+8);
61
62                         if (generation > 0)
63                                 sprintf(new_name, "%s~%d^%d", tip_name,
64                                                 generation, parent_number);
65                         else
66                                 sprintf(new_name, "%s^%d", tip_name, parent_number);
67
68                         name_rev(parents->item, new_name,
69                                 merge_traversals + 1 , 0, 0);
70                 } else {
71                         name_rev(parents->item, tip_name, merge_traversals,
72                                 generation + 1, 0);
73                 }
74         }
75 }
76
77 static int name_ref(const char *path, const unsigned char *sha1, int flags, void *cb_data)
78 {
79         struct object *o = parse_object(sha1);
80         int tags_only = *(int*)cb_data;
81         int deref = 0;
82
83         if (tags_only && strncmp(path, "refs/tags/", 10))
84                 return 0;
85
86         while (o && o->type == OBJ_TAG) {
87                 struct tag *t = (struct tag *) o;
88                 if (!t->tagged)
89                         break; /* broken repository */
90                 o = parse_object(t->tagged->sha1);
91                 deref = 1;
92         }
93         if (o && o->type == OBJ_COMMIT) {
94                 struct commit *commit = (struct commit *)o;
95
96                 if (!strncmp(path, "refs/heads/", 11))
97                         path = path + 11;
98                 else if (!strncmp(path, "refs/", 5))
99                         path = path + 5;
100
101                 name_rev(commit, xstrdup(path), 0, 0, deref);
102         }
103         return 0;
104 }
105
106 /* returns a static buffer */
107 static const char* get_rev_name(struct object *o)
108 {
109         static char buffer[1024];
110         struct rev_name *n;
111         struct commit *c;
112
113         if (o->type != OBJ_COMMIT)
114                 return "undefined";
115         c = (struct commit *) o;
116         n = c->util;
117         if (!n)
118                 return "undefined";
119
120         if (!n->generation)
121                 return n->tip_name;
122
123         snprintf(buffer, sizeof(buffer), "%s~%d", n->tip_name, n->generation);
124
125         return buffer;
126 }
127
128 int cmd_name_rev(int argc, const char **argv, const char *prefix)
129 {
130         struct object_array revs = { 0, 0, NULL };
131         int as_is = 0, all = 0, transform_stdin = 0;
132         int tags_only = 0;
133
134         git_config(git_default_config);
135
136         if (argc < 2)
137                 usage(name_rev_usage);
138
139         for (--argc, ++argv; argc; --argc, ++argv) {
140                 unsigned char sha1[20];
141                 struct object *o;
142                 struct commit *commit;
143
144                 if (!as_is && (*argv)[0] == '-') {
145                         if (!strcmp(*argv, "--")) {
146                                 as_is = 1;
147                                 continue;
148                         } else if (!strcmp(*argv, "--tags")) {
149                                 tags_only = 1;
150                                 continue;
151                         } else if (!strcmp(*argv, "--all")) {
152                                 if (argc > 1)
153                                         die("Specify either a list, or --all, not both!");
154                                 all = 1;
155                                 cutoff = 0;
156                                 continue;
157                         } else if (!strcmp(*argv, "--stdin")) {
158                                 if (argc > 1)
159                                         die("Specify either a list, or --stdin, not both!");
160                                 transform_stdin = 1;
161                                 cutoff = 0;
162                                 continue;
163                         }
164                         usage(name_rev_usage);
165                 }
166
167                 if (get_sha1(*argv, sha1)) {
168                         fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
169                                         *argv);
170                         continue;
171                 }
172
173                 o = deref_tag(parse_object(sha1), *argv, 0);
174                 if (!o || o->type != OBJ_COMMIT) {
175                         fprintf(stderr, "Could not get commit for %s. Skipping.\n",
176                                         *argv);
177                         continue;
178                 }
179
180                 commit = (struct commit *)o;
181
182                 if (cutoff > commit->date)
183                         cutoff = commit->date;
184
185                 add_object_array((struct object *)commit, *argv, &revs);
186         }
187
188         for_each_ref(name_ref, &tags_only);
189
190         if (transform_stdin) {
191                 char buffer[2048];
192                 char *p, *p_start;
193
194                 while (!feof(stdin)) {
195                         int forty = 0;
196                         p = fgets(buffer, sizeof(buffer), stdin);
197                         if (!p)
198                                 break;
199
200                         for (p_start = p; *p; p++) {
201 #define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
202                                 if (!ishex(*p))
203                                         forty = 0;
204                                 else if (++forty == 40 &&
205                                                 !ishex(*(p+1))) {
206                                         unsigned char sha1[40];
207                                         const char *name = "undefined";
208                                         char c = *(p+1);
209
210                                         forty = 0;
211
212                                         *(p+1) = 0;
213                                         if (!get_sha1(p - 39, sha1)) {
214                                                 struct object *o =
215                                                         lookup_object(sha1);
216                                                 if (o)
217                                                         name = get_rev_name(o);
218                                         }
219                                         *(p+1) = c;
220
221                                         if (!strcmp(name, "undefined"))
222                                                 continue;
223
224                                         fwrite(p_start, p - p_start + 1, 1,
225                                                stdout);
226                                         printf(" (%s)", name);
227                                         p_start = p + 1;
228                                 }
229                         }
230
231                         /* flush */
232                         if (p_start != p)
233                                 fwrite(p_start, p - p_start, 1, stdout);
234                 }
235         } else if (all) {
236                 int i, max;
237
238                 max = get_max_object_index();
239                 for (i = 0; i < max; i++) {
240                         struct object * obj = get_indexed_object(i);
241                         if (!obj)
242                                 continue;
243                         printf("%s %s\n", sha1_to_hex(obj->sha1), get_rev_name(obj));
244                 }
245         } else {
246                 int i;
247                 for (i = 0; i < revs.nr; i++)
248                         printf("%s %s\n",
249                                 revs.objects[i].name,
250                                 get_rev_name(revs.objects[i].item));
251         }
252
253         return 0;
254 }
255