1 /*
2 * libgit2 "init" example - shows how to initialize a new repo
3 *
4 * Written by the libgit2 contributors
5 *
6 * To the extent possible under law, the author(s) have dedicated all copyright
7 * and related and neighboring rights to this software to the public domain
8 * worldwide. This software is distributed without any warranty.
9 *
10 * You should have received a copy of the CC0 Public Domain Dedication along
11 * with this software. If not, see
12 * <http://creativecommons.org/publicdomain/zero/1.0/>.
13 */
14
15 #include "common.h"
16
17 /**
18 * This is a sample program that is similar to "git init". See the
19 * documentation for that (try "git help init") to understand what this
20 * program is emulating.
21 *
22 * This demonstrates using the libgit2 APIs to initialize a new repository.
23 *
24 * This also contains a special additional option that regular "git init"
25 * does not support which is "--initial-commit" to make a first empty commit.
26 * That is demonstrated in the "create_initial_commit" helper function.
27 */
28
29 /** Forward declarations of helpers */
30 struct opts {
31 int no_options;
32 int quiet;
33 int bare;
34 int initial_commit;
35 uint32_t shared;
36 const char *template;
37 const char *gitdir;
38 const char *dir;
39 };
40 static void create_initial_commit(git_repository *repo);
41 static void parse_opts(struct opts *o, int argc, char *argv[]);
42
43
main(int argc,char * argv[])44 int main(int argc, char *argv[])
45 {
46 git_repository *repo = NULL;
47 struct opts o = { 1, 0, 0, 0, GIT_REPOSITORY_INIT_SHARED_UMASK, 0, 0, 0 };
48
49 git_libgit2_init();
50
51 parse_opts(&o, argc, argv);
52
53 /* Initialize repository. */
54
55 if (o.no_options) {
56 /**
57 * No options were specified, so let's demonstrate the default
58 * simple case of git_repository_init() API usage...
59 */
60 check_lg2(git_repository_init(&repo, o.dir, 0),
61 "Could not initialize repository", NULL);
62 }
63 else {
64 /**
65 * Some command line options were specified, so we'll use the
66 * extended init API to handle them
67 */
68 git_repository_init_options initopts = GIT_REPOSITORY_INIT_OPTIONS_INIT;
69 initopts.flags = GIT_REPOSITORY_INIT_MKPATH;
70
71 if (o.bare)
72 initopts.flags |= GIT_REPOSITORY_INIT_BARE;
73
74 if (o.template) {
75 initopts.flags |= GIT_REPOSITORY_INIT_EXTERNAL_TEMPLATE;
76 initopts.template_path = o.template;
77 }
78
79 if (o.gitdir) {
80 /**
81 * If you specified a separate git directory, then initialize
82 * the repository at that path and use the second path as the
83 * working directory of the repository (with a git-link file)
84 */
85 initopts.workdir_path = o.dir;
86 o.dir = o.gitdir;
87 }
88
89 if (o.shared != 0)
90 initopts.mode = o.shared;
91
92 check_lg2(git_repository_init_ext(&repo, o.dir, &initopts),
93 "Could not initialize repository", NULL);
94 }
95
96 /** Print a message to stdout like "git init" does. */
97
98 if (!o.quiet) {
99 if (o.bare || o.gitdir)
100 o.dir = git_repository_path(repo);
101 else
102 o.dir = git_repository_workdir(repo);
103
104 printf("Initialized empty Git repository in %s\n", o.dir);
105 }
106
107 /**
108 * As an extension to the basic "git init" command, this example
109 * gives the option to create an empty initial commit. This is
110 * mostly to demonstrate what it takes to do that, but also some
111 * people like to have that empty base commit in their repo.
112 */
113 if (o.initial_commit) {
114 create_initial_commit(repo);
115 printf("Created empty initial commit\n");
116 }
117
118 git_repository_free(repo);
119 git_libgit2_shutdown();
120
121 return 0;
122 }
123
124 /**
125 * Unlike regular "git init", this example shows how to create an initial
126 * empty commit in the repository. This is the helper function that does
127 * that.
128 */
create_initial_commit(git_repository * repo)129 static void create_initial_commit(git_repository *repo)
130 {
131 git_signature *sig;
132 git_index *index;
133 git_oid tree_id, commit_id;
134 git_tree *tree;
135
136 /** First use the config to initialize a commit signature for the user. */
137
138 if (git_signature_default(&sig, repo) < 0)
139 fatal("Unable to create a commit signature.",
140 "Perhaps 'user.name' and 'user.email' are not set");
141
142 /* Now let's create an empty tree for this commit */
143
144 if (git_repository_index(&index, repo) < 0)
145 fatal("Could not open repository index", NULL);
146
147 /**
148 * Outside of this example, you could call git_index_add_bypath()
149 * here to put actual files into the index. For our purposes, we'll
150 * leave it empty for now.
151 */
152
153 if (git_index_write_tree(&tree_id, index) < 0)
154 fatal("Unable to write initial tree from index", NULL);
155
156 git_index_free(index);
157
158 if (git_tree_lookup(&tree, repo, &tree_id) < 0)
159 fatal("Could not look up initial tree", NULL);
160
161 /**
162 * Ready to create the initial commit.
163 *
164 * Normally creating a commit would involve looking up the current
165 * HEAD commit and making that be the parent of the initial commit,
166 * but here this is the first commit so there will be no parent.
167 */
168
169 if (git_commit_create_v(
170 &commit_id, repo, "HEAD", sig, sig,
171 NULL, "Initial commit", tree, 0) < 0)
172 fatal("Could not create the initial commit", NULL);
173
174 /** Clean up so we don't leak memory. */
175
176 git_tree_free(tree);
177 git_signature_free(sig);
178 }
179
usage(const char * error,const char * arg)180 static void usage(const char *error, const char *arg)
181 {
182 fprintf(stderr, "error: %s '%s'\n", error, arg);
183 fprintf(stderr,
184 "usage: init [-q | --quiet] [--bare] [--template=<dir>]\n"
185 " [--shared[=perms]] [--initial-commit]\n"
186 " [--separate-git-dir] <directory>\n");
187 exit(1);
188 }
189
190 /** Parse the tail of the --shared= argument. */
parse_shared(const char * shared)191 static uint32_t parse_shared(const char *shared)
192 {
193 if (!strcmp(shared, "false") || !strcmp(shared, "umask"))
194 return GIT_REPOSITORY_INIT_SHARED_UMASK;
195
196 else if (!strcmp(shared, "true") || !strcmp(shared, "group"))
197 return GIT_REPOSITORY_INIT_SHARED_GROUP;
198
199 else if (!strcmp(shared, "all") || !strcmp(shared, "world") ||
200 !strcmp(shared, "everybody"))
201 return GIT_REPOSITORY_INIT_SHARED_ALL;
202
203 else if (shared[0] == '0') {
204 long val;
205 char *end = NULL;
206 val = strtol(shared + 1, &end, 8);
207 if (end == shared + 1 || *end != 0)
208 usage("invalid octal value for --shared", shared);
209 return (uint32_t)val;
210 }
211
212 else
213 usage("unknown value for --shared", shared);
214
215 return 0;
216 }
217
parse_opts(struct opts * o,int argc,char * argv[])218 static void parse_opts(struct opts *o, int argc, char *argv[])
219 {
220 struct args_info args = ARGS_INFO_INIT;
221 const char *sharedarg;
222
223 /** Process arguments. */
224
225 for (args.pos = 1; args.pos < argc; ++args.pos) {
226 char *a = argv[args.pos];
227
228 if (a[0] == '-')
229 o->no_options = 0;
230
231 if (a[0] != '-') {
232 if (o->dir != NULL)
233 usage("extra argument", a);
234 o->dir = a;
235 }
236 else if (!strcmp(a, "-q") || !strcmp(a, "--quiet"))
237 o->quiet = 1;
238 else if (!strcmp(a, "--bare"))
239 o->bare = 1;
240 else if (!strcmp(a, "--shared"))
241 o->shared = GIT_REPOSITORY_INIT_SHARED_GROUP;
242 else if (!strcmp(a, "--initial-commit"))
243 o->initial_commit = 1;
244 else if (match_str_arg(&sharedarg, &args, "--shared"))
245 o->shared = parse_shared(sharedarg);
246 else if (!match_str_arg(&o->template, &args, "--template") ||
247 !match_str_arg(&o->gitdir, &args, "--separate-git-dir"))
248 usage("unknown option", a);
249 }
250
251 if (!o->dir)
252 usage("must specify directory to init", NULL);
253 }
254