Make some strings const
[git/git.git] / git.c
1 #include <stdio.h>
2 #include <sys/types.h>
3 #include <sys/stat.h>
4 #include <dirent.h>
5 #include <unistd.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <errno.h>
9 #include <limits.h>
10 #include <stdarg.h>
11 #include "git-compat-util.h"
12 #include "exec_cmd.h"
13 #include "cache.h"
14
15 #include "builtin.h"
16
17 static void prepend_to_path(const char *dir, int len)
18 {
19 const char *old_path = getenv("PATH");
20 char *path;
21 int path_len = len;
22
23 if (!old_path)
24 old_path = "/usr/local/bin:/usr/bin:/bin";
25
26 path_len = len + strlen(old_path) + 1;
27
28 path = malloc(path_len + 1);
29
30 memcpy(path, dir, len);
31 path[len] = ':';
32 memcpy(path + len + 1, old_path, path_len - len);
33
34 setenv("PATH", path, 1);
35 }
36
37 static const char *alias_command;
38 static char *alias_string = NULL;
39
40 static int git_alias_config(const char *var, const char *value)
41 {
42 if (!strncmp(var, "alias.", 6) && !strcmp(var + 6, alias_command)) {
43 alias_string = strdup(value);
44 }
45 return 0;
46 }
47
48 static int split_cmdline(char *cmdline, const char ***argv)
49 {
50 int src, dst, count = 0, size = 16;
51 char quoted = 0;
52
53 *argv = malloc(sizeof(char*) * size);
54
55 /* split alias_string */
56 (*argv)[count++] = cmdline;
57 for (src = dst = 0; cmdline[src];) {
58 char c = cmdline[src];
59 if (!quoted && isspace(c)) {
60 cmdline[dst++] = 0;
61 while (cmdline[++src]
62 && isspace(cmdline[src]))
63 ; /* skip */
64 if (count >= size) {
65 size += 16;
66 *argv = realloc(*argv, sizeof(char*) * size);
67 }
68 (*argv)[count++] = cmdline + dst;
69 } else if(!quoted && (c == '\'' || c == '"')) {
70 quoted = c;
71 src++;
72 } else if (c == quoted) {
73 quoted = 0;
74 src++;
75 } else {
76 if (c == '\\' && quoted != '\'') {
77 src++;
78 c = cmdline[src];
79 if (!c) {
80 free(*argv);
81 *argv = NULL;
82 return error("cmdline ends with \\");
83 }
84 }
85 cmdline[dst++] = c;
86 src++;
87 }
88 }
89
90 cmdline[dst] = 0;
91
92 if (quoted) {
93 free(*argv);
94 *argv = NULL;
95 return error("unclosed quote");
96 }
97
98 return count;
99 }
100
101 static int handle_alias(int *argcp, const char ***argv)
102 {
103 int nongit = 0, ret = 0;
104 const char *subdir;
105
106 subdir = setup_git_directory_gently(&nongit);
107 if (!nongit) {
108 int count;
109 const char** new_argv;
110
111 alias_command = (*argv)[0];
112 git_config(git_alias_config);
113 if (alias_string) {
114
115 count = split_cmdline(alias_string, &new_argv);
116
117 if (count < 1)
118 die("empty alias for %s", alias_command);
119
120 if (!strcmp(alias_command, new_argv[0]))
121 die("recursive alias: %s", alias_command);
122
123 /* insert after command name */
124 if (*argcp > 1) {
125 new_argv = realloc(new_argv, sizeof(char*) *
126 (count + *argcp));
127 memcpy(new_argv + count, *argv + 1,
128 sizeof(char*) * *argcp);
129 }
130
131 *argv = new_argv;
132 *argcp += count - 1;
133
134 ret = 1;
135 }
136 }
137
138 if (subdir)
139 chdir(subdir);
140
141 return ret;
142 }
143
144 const char git_version_string[] = GIT_VERSION;
145
146 static void handle_internal_command(int argc, const char **argv, char **envp)
147 {
148 const char *cmd = argv[0];
149 static struct cmd_struct {
150 const char *cmd;
151 int (*fn)(int, const char **, char **);
152 } commands[] = {
153 { "version", cmd_version },
154 { "help", cmd_help },
155 { "log", cmd_log },
156 { "whatchanged", cmd_whatchanged },
157 { "show", cmd_show },
158 { "push", cmd_push },
159 { "format-patch", cmd_format_patch },
160 { "count-objects", cmd_count_objects },
161 { "diff", cmd_diff },
162 { "grep", cmd_grep },
163 { "rm", cmd_rm },
164 { "add", cmd_add },
165 { "rev-list", cmd_rev_list },
166 { "init-db", cmd_init_db },
167 { "get-tar-commit-id", cmd_get_tar_commit_id },
168 { "upload-tar", cmd_upload_tar },
169 { "check-ref-format", cmd_check_ref_format },
170 { "ls-files", cmd_ls_files },
171 { "ls-tree", cmd_ls_tree },
172 { "tar-tree", cmd_tar_tree },
173 { "read-tree", cmd_read_tree },
174 { "commit-tree", cmd_commit_tree },
175 { "apply", cmd_apply },
176 { "show-branch", cmd_show_branch },
177 { "diff-files", cmd_diff_files },
178 { "diff-index", cmd_diff_index },
179 { "diff-stages", cmd_diff_stages },
180 { "diff-tree", cmd_diff_tree },
181 { "cat-file", cmd_cat_file },
182 { "rev-parse", cmd_rev_parse },
183 { "write-tree", cmd_write_tree },
184 { "mailsplit", cmd_mailsplit },
185 { "mailinfo", cmd_mailinfo },
186 { "stripspace", cmd_stripspace },
187 { "update-index", cmd_update_index },
188 { "update-ref", cmd_update_ref }
189 };
190 int i;
191
192 /* Turn "git cmd --help" into "git help cmd" */
193 if (argc > 1 && !strcmp(argv[1], "--help")) {
194 argv[1] = argv[0];
195 argv[0] = cmd = "help";
196 }
197
198 for (i = 0; i < ARRAY_SIZE(commands); i++) {
199 struct cmd_struct *p = commands+i;
200 if (strcmp(p->cmd, cmd))
201 continue;
202 exit(p->fn(argc, argv, envp));
203 }
204 }
205
206 int main(int argc, const char **argv, char **envp)
207 {
208 const char *cmd = argv[0];
209 char *slash = strrchr(cmd, '/');
210 const char *exec_path = NULL;
211 int done_alias = 0;
212
213 /*
214 * Take the basename of argv[0] as the command
215 * name, and the dirname as the default exec_path
216 * if it's an absolute path and we don't have
217 * anything better.
218 */
219 if (slash) {
220 *slash++ = 0;
221 if (*cmd == '/')
222 exec_path = cmd;
223 cmd = slash;
224 }
225
226 /*
227 * "git-xxxx" is the same as "git xxxx", but we obviously:
228 *
229 * - cannot take flags in between the "git" and the "xxxx".
230 * - cannot execute it externally (since it would just do
231 * the same thing over again)
232 *
233 * So we just directly call the internal command handler, and
234 * die if that one cannot handle it.
235 */
236 if (!strncmp(cmd, "git-", 4)) {
237 cmd += 4;
238 argv[0] = cmd;
239 handle_internal_command(argc, argv, envp);
240 die("cannot handle %s internally", cmd);
241 }
242
243 /* Default command: "help" */
244 cmd = "help";
245
246 /* Look for flags.. */
247 while (argc > 1) {
248 cmd = *++argv;
249 argc--;
250
251 if (strncmp(cmd, "--", 2))
252 break;
253
254 cmd += 2;
255
256 /*
257 * For legacy reasons, the "version" and "help"
258 * commands can be written with "--" prepended
259 * to make them look like flags.
260 */
261 if (!strcmp(cmd, "help"))
262 break;
263 if (!strcmp(cmd, "version"))
264 break;
265
266 /*
267 * Check remaining flags (which by now must be
268 * "--exec-path", but maybe we will accept
269 * other arguments some day)
270 */
271 if (!strncmp(cmd, "exec-path", 9)) {
272 cmd += 9;
273 if (*cmd == '=') {
274 git_set_exec_path(cmd + 1);
275 continue;
276 }
277 puts(git_exec_path());
278 exit(0);
279 }
280 cmd_usage(0, NULL, NULL);
281 }
282 argv[0] = cmd;
283
284 /*
285 * We search for git commands in the following order:
286 * - git_exec_path()
287 * - the path of the "git" command if we could find it
288 * in $0
289 * - the regular PATH.
290 */
291 if (exec_path)
292 prepend_to_path(exec_path, strlen(exec_path));
293 exec_path = git_exec_path();
294 prepend_to_path(exec_path, strlen(exec_path));
295
296 while (1) {
297 /* See if it's an internal command */
298 handle_internal_command(argc, argv, envp);
299
300 /* .. then try the external ones */
301 execv_git_cmd(argv);
302
303 /* It could be an alias -- this works around the insanity
304 * of overriding "git log" with "git show" by having
305 * alias.log = show
306 */
307 if (done_alias || !handle_alias(&argc, &argv))
308 break;
309 done_alias = 1;
310 }
311
312 if (errno == ENOENT)
313 cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
314
315 fprintf(stderr, "Failed to run command '%s': %s\n",
316 cmd, strerror(errno));
317
318 return 1;
319 }