Teach receive-pack how to keep pack files based on object count.
[git] / builtin-branch.c
1 /*
2  * Builtin "git branch"
3  *
4  * Copyright (c) 2006 Kristian Høgsberg <krh@redhat.com>
5  * Based on git-branch.sh by Junio C Hamano.
6  */
7
8 #include "cache.h"
9 #include "refs.h"
10 #include "commit.h"
11 #include "builtin.h"
12
13 static const char builtin_branch_usage[] =
14 "git-branch (-d | -D) <branchname> | [-l] [-f] <branchname> [<start-point>] | [-r]";
15
16
17 static const char *head;
18 static unsigned char head_sha1[20];
19
20 static int in_merge_bases(const unsigned char *sha1,
21                           struct commit *rev1,
22                           struct commit *rev2)
23 {
24         struct commit_list *bases, *b;
25         int ret = 0;
26
27         bases = get_merge_bases(rev1, rev2, 1);
28         for (b = bases; b; b = b->next) {
29                 if (!hashcmp(sha1, b->item->object.sha1)) {
30                         ret = 1;
31                         break;
32                 }
33         }
34
35         free_commit_list(bases);
36         return ret;
37 }
38
39 static void delete_branches(int argc, const char **argv, int force)
40 {
41         struct commit *rev, *head_rev;
42         unsigned char sha1[20];
43         char *name;
44         int i;
45
46         head_rev = lookup_commit_reference(head_sha1);
47         for (i = 0; i < argc; i++) {
48                 if (!strcmp(head, argv[i]))
49                         die("Cannot delete the branch you are currently on.");
50
51                 name = xstrdup(mkpath("refs/heads/%s", argv[i]));
52                 if (!resolve_ref(name, sha1, 1, NULL))
53                         die("Branch '%s' not found.", argv[i]);
54
55                 rev = lookup_commit_reference(sha1);
56                 if (!rev || !head_rev)
57                         die("Couldn't look up commit objects.");
58
59                 /* This checks whether the merge bases of branch and
60                  * HEAD contains branch -- which means that the HEAD
61                  * contains everything in both.
62                  */
63
64                 if (!force &&
65                     !in_merge_bases(sha1, rev, head_rev)) {
66                         fprintf(stderr,
67                                 "The branch '%s' is not a strict subset of your current HEAD.\n"
68                                 "If you are sure you want to delete it, run 'git branch -D %s'.\n",
69                                 argv[i], argv[i]);
70                         exit(1);
71                 }
72
73                 if (delete_ref(name, sha1))
74                         printf("Error deleting branch '%s'\n", argv[i]);
75                 else
76                         printf("Deleted branch %s.\n", argv[i]);
77
78                 free(name);
79         }
80 }
81
82 static int ref_index, ref_alloc;
83 static char **ref_list;
84
85 static int append_ref(const char *refname, const unsigned char *sha1, int flags,
86                 void *cb_data)
87 {
88         if (ref_index >= ref_alloc) {
89                 ref_alloc = alloc_nr(ref_alloc);
90                 ref_list = xrealloc(ref_list, ref_alloc * sizeof(char *));
91         }
92
93         ref_list[ref_index++] = xstrdup(refname);
94
95         return 0;
96 }
97
98 static int ref_cmp(const void *r1, const void *r2)
99 {
100         return strcmp(*(char **)r1, *(char **)r2);
101 }
102
103 static void print_ref_list(int remote_only)
104 {
105         int i;
106         char c;
107
108         if (remote_only)
109                 for_each_remote_ref(append_ref, NULL);
110         else
111                 for_each_branch_ref(append_ref, NULL);
112
113         qsort(ref_list, ref_index, sizeof(char *), ref_cmp);
114
115         for (i = 0; i < ref_index; i++) {
116                 c = ' ';
117                 if (!strcmp(ref_list[i], head))
118                         c = '*';
119
120                 printf("%c %s\n", c, ref_list[i]);
121         }
122 }
123
124 static void create_branch(const char *name, const char *start,
125                           int force, int reflog)
126 {
127         struct ref_lock *lock;
128         struct commit *commit;
129         unsigned char sha1[20];
130         char ref[PATH_MAX], msg[PATH_MAX + 20];
131
132         snprintf(ref, sizeof ref, "refs/heads/%s", name);
133         if (check_ref_format(ref))
134                 die("'%s' is not a valid branch name.", name);
135
136         if (resolve_ref(ref, sha1, 1, NULL)) {
137                 if (!force)
138                         die("A branch named '%s' already exists.", name);
139                 else if (!strcmp(head, name))
140                         die("Cannot force update the current branch.");
141         }
142
143         if (get_sha1(start, sha1) ||
144             (commit = lookup_commit_reference(sha1)) == NULL)
145                 die("Not a valid branch point: '%s'.", start);
146         hashcpy(sha1, commit->object.sha1);
147
148         lock = lock_any_ref_for_update(ref, NULL);
149         if (!lock)
150                 die("Failed to lock ref for update: %s.", strerror(errno));
151
152         if (reflog) {
153                 log_all_ref_updates = 1;
154                 snprintf(msg, sizeof msg, "branch: Created from %s", start);
155         }
156
157         if (write_ref_sha1(lock, sha1, msg) < 0)
158                 die("Failed to write ref: %s.", strerror(errno));
159 }
160
161 int cmd_branch(int argc, const char **argv, const char *prefix)
162 {
163         int delete = 0, force_delete = 0, force_create = 0, remote_only = 0;
164         int reflog = 0;
165         int i;
166
167         git_config(git_default_config);
168
169         for (i = 1; i < argc; i++) {
170                 const char *arg = argv[i];
171
172                 if (arg[0] != '-')
173                         break;
174                 if (!strcmp(arg, "--")) {
175                         i++;
176                         break;
177                 }
178                 if (!strcmp(arg, "-d")) {
179                         delete = 1;
180                         continue;
181                 }
182                 if (!strcmp(arg, "-D")) {
183                         delete = 1;
184                         force_delete = 1;
185                         continue;
186                 }
187                 if (!strcmp(arg, "-f")) {
188                         force_create = 1;
189                         continue;
190                 }
191                 if (!strcmp(arg, "-r")) {
192                         remote_only = 1;
193                         continue;
194                 }
195                 if (!strcmp(arg, "-l")) {
196                         reflog = 1;
197                         continue;
198                 }
199                 usage(builtin_branch_usage);
200         }
201
202         head = xstrdup(resolve_ref("HEAD", head_sha1, 0, NULL));
203         if (!head)
204                 die("Failed to resolve HEAD as a valid ref.");
205         if (strncmp(head, "refs/heads/", 11))
206                 die("HEAD not found below refs/heads!");
207         head += 11;
208
209         if (delete)
210                 delete_branches(argc - i, argv + i, force_delete);
211         else if (i == argc)
212                 print_ref_list(remote_only);
213         else if (i == argc - 1)
214                 create_branch(argv[i], head, force_create, reflog);
215         else if (i == argc - 2)
216                 create_branch(argv[i], argv[i + 1], force_create, reflog);
217         else
218                 usage(builtin_branch_usage);
219
220         return 0;
221 }