Builtin git-show-branch.
[git/git.git] / git.c
CommitLineData
8e49d503 1#include <stdio.h>
7dbc2c04
JH
2#include <sys/types.h>
3#include <sys/stat.h>
4#include <dirent.h>
8e49d503
AE
5#include <unistd.h>
6#include <stdlib.h>
7#include <string.h>
8#include <errno.h>
9#include <limits.h>
10#include <stdarg.h>
4050c0df 11#include "git-compat-util.h"
77cb17e9 12#include "exec_cmd.h"
8e49d503 13
70827b15 14#include "builtin.h"
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AE
15
16static void prepend_to_path(const char *dir, int len)
17{
18 char *path, *old_path = getenv("PATH");
19 int path_len = len;
20
21 if (!old_path)
7dbc2c04 22 old_path = "/usr/local/bin:/usr/bin:/bin";
8e49d503
AE
23
24 path_len = len + strlen(old_path) + 1;
25
26 path = malloc(path_len + 1);
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AE
27
28 memcpy(path, dir, len);
29 path[len] = ':';
30 memcpy(path + len + 1, old_path, path_len - len);
31
32 setenv("PATH", path, 1);
33}
34
70827b15 35const char git_version_string[] = GIT_VERSION;
5b84f4d8 36
9201c707 37static void handle_internal_command(int argc, const char **argv, char **envp)
231af832
LT
38{
39 const char *cmd = argv[0];
40 static struct cmd_struct {
41 const char *cmd;
9201c707 42 int (*fn)(int, const char **, char **);
231af832
LT
43 } commands[] = {
44 { "version", cmd_version },
45 { "help", cmd_help },
70b006b9 46 { "log", cmd_log },
70827b15 47 { "whatchanged", cmd_whatchanged },
ba1d4505 48 { "show", cmd_show },
755225de 49 { "push", cmd_push },
c7432087 50 { "count-objects", cmd_count_objects },
8ab99476 51 { "diff", cmd_diff },
5010cb5f 52 { "grep", cmd_grep },
5fb61b8d 53 { "rev-list", cmd_rev_list },
c3c8835f 54 { "init-db", cmd_init_db },
0864f264 55 { "check-ref-format", cmd_check_ref_format },
aae01bda 56 { "ls-files", cmd_ls_files },
56d1398a 57 { "ls-tree", cmd_ls_tree },
d147e501 58 { "tar-tree", cmd_tar_tree },
6d96ac18 59 { "read-tree", cmd_read_tree },
ac6245e3 60 { "commit-tree", cmd_commit_tree },
51ce34b9
PE
61 { "apply", cmd_apply },
62 { "show-branch", cmd_show_branch }
231af832
LT
63 };
64 int i;
65
1cd95087
LT
66 /* Turn "git cmd --help" into "git help cmd" */
67 if (argc > 1 && !strcmp(argv[1], "--help")) {
68 argv[1] = argv[0];
69 argv[0] = cmd = "help";
70 }
71
231af832
LT
72 for (i = 0; i < ARRAY_SIZE(commands); i++) {
73 struct cmd_struct *p = commands+i;
74 if (strcmp(p->cmd, cmd))
75 continue;
76 exit(p->fn(argc, argv, envp));
77 }
78}
79
9201c707 80int main(int argc, const char **argv, char **envp)
8e49d503 81{
9201c707 82 const char *cmd = argv[0];
231af832 83 char *slash = strrchr(cmd, '/');
8e49d503 84 char git_command[PATH_MAX + 1];
231af832
LT
85 const char *exec_path = NULL;
86
87 /*
88 * Take the basename of argv[0] as the command
89 * name, and the dirname as the default exec_path
90 * if it's an absolute path and we don't have
91 * anything better.
92 */
93 if (slash) {
94 *slash++ = 0;
95 if (*cmd == '/')
96 exec_path = cmd;
97 cmd = slash;
98 }
8e49d503 99
231af832
LT
100 /*
101 * "git-xxxx" is the same as "git xxxx", but we obviously:
102 *
103 * - cannot take flags in between the "git" and the "xxxx".
104 * - cannot execute it externally (since it would just do
105 * the same thing over again)
106 *
107 * So we just directly call the internal command handler, and
108 * die if that one cannot handle it.
109 */
110 if (!strncmp(cmd, "git-", 4)) {
111 cmd += 4;
112 argv[0] = cmd;
113 handle_internal_command(argc, argv, envp);
114 die("cannot handle %s internally", cmd);
115 }
8e49d503 116
231af832
LT
117 /* Default command: "help" */
118 cmd = "help";
8e49d503 119
231af832
LT
120 /* Look for flags.. */
121 while (argc > 1) {
122 cmd = *++argv;
123 argc--;
da6bf70e 124
231af832 125 if (strncmp(cmd, "--", 2))
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AE
126 break;
127
231af832
LT
128 cmd += 2;
129
130 /*
131 * For legacy reasons, the "version" and "help"
132 * commands can be written with "--" prepended
133 * to make them look like flags.
134 */
135 if (!strcmp(cmd, "help"))
136 break;
137 if (!strcmp(cmd, "version"))
138 break;
8e49d503 139
231af832
LT
140 /*
141 * Check remaining flags (which by now must be
142 * "--exec-path", but maybe we will accept
143 * other arguments some day)
144 */
145 if (!strncmp(cmd, "exec-path", 9)) {
146 cmd += 9;
147 if (*cmd == '=') {
148 git_set_exec_path(cmd + 1);
149 continue;
8e49d503 150 }
231af832 151 puts(git_exec_path());
8e49d503
AE
152 exit(0);
153 }
a87cd02c 154 cmd_usage(0, NULL, NULL);
97fc6c5f 155 }
231af832
LT
156 argv[0] = cmd;
157
158 /*
159 * We search for git commands in the following order:
160 * - git_exec_path()
161 * - the path of the "git" command if we could find it
162 * in $0
163 * - the regular PATH.
164 */
165 if (exec_path)
166 prepend_to_path(exec_path, strlen(exec_path));
77cb17e9
MO
167 exec_path = git_exec_path();
168 prepend_to_path(exec_path, strlen(exec_path));
8e49d503 169
231af832
LT
170 /* See if it's an internal command */
171 handle_internal_command(argc, argv, envp);
172
173 /* .. then try the external ones */
174 execv_git_cmd(argv);
10b15b86
AR
175
176 if (errno == ENOENT)
a87cd02c 177 cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
10b15b86
AR
178
179 fprintf(stderr, "Failed to run command '%s': %s\n",
180 git_command, strerror(errno));
8e49d503
AE
181
182 return 1;
183}