Teach "approxidate" about weekday syntax
[git/jrn.git] / git.c
blobb9b8c62f47cc54ef03161e61569dcd0d7b259828
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>
12 #ifndef PATH_MAX
13 # define PATH_MAX 4096
14 #endif
16 static const char git_usage[] =
17 "Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]";
19 /* most gui terms set COLUMNS (although some don't export it) */
20 static int term_columns(void)
22 char *col_string = getenv("COLUMNS");
23 int n_cols = 0;
25 if (col_string && (n_cols = atoi(col_string)) > 0)
26 return n_cols;
28 return 80;
31 static void oom(void)
33 fprintf(stderr, "git: out of memory\n");
34 exit(1);
37 static inline void mput_char(char c, unsigned int num)
39 while(num--)
40 putchar(c);
43 static struct cmdname {
44 size_t len;
45 char name[1];
46 } **cmdname;
47 static int cmdname_alloc, cmdname_cnt;
49 static void add_cmdname(const char *name, int len)
51 struct cmdname *ent;
52 if (cmdname_alloc <= cmdname_cnt) {
53 cmdname_alloc = cmdname_alloc + 200;
54 cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
55 if (!cmdname)
56 oom();
58 ent = malloc(sizeof(*ent) + len);
59 if (!ent)
60 oom();
61 ent->len = len;
62 memcpy(ent->name, name, len+1);
63 cmdname[cmdname_cnt++] = ent;
66 static int cmdname_compare(const void *a_, const void *b_)
68 struct cmdname *a = *(struct cmdname **)a_;
69 struct cmdname *b = *(struct cmdname **)b_;
70 return strcmp(a->name, b->name);
73 static void pretty_print_string_list(struct cmdname **cmdname, int longest)
75 int cols = 1;
76 int space = longest + 1; /* min 1 SP between words */
77 int max_cols = term_columns() - 1; /* don't print *on* the edge */
78 int i;
80 if (space < max_cols)
81 cols = max_cols / space;
83 qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
85 for (i = 0; i < cmdname_cnt; ) {
86 int c;
87 printf(" ");
89 for (c = cols; c && i < cmdname_cnt; i++) {
90 printf("%s", cmdname[i]->name);
92 if (--c)
93 mput_char(' ', space - cmdname[i]->len);
95 putchar('\n');
99 static void list_commands(const char *exec_path, const char *pattern)
101 unsigned int longest = 0;
102 char path[PATH_MAX];
103 int dirlen;
104 DIR *dir = opendir(exec_path);
105 struct dirent *de;
107 if (!dir) {
108 fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
109 exit(1);
112 dirlen = strlen(exec_path);
113 if (PATH_MAX - 20 < dirlen) {
114 fprintf(stderr, "git: insanely long exec-path '%s'\n",
115 exec_path);
116 exit(1);
119 memcpy(path, exec_path, dirlen);
120 path[dirlen++] = '/';
122 while ((de = readdir(dir)) != NULL) {
123 struct stat st;
124 int entlen;
126 if (strncmp(de->d_name, "git-", 4))
127 continue;
128 strcpy(path+dirlen, de->d_name);
129 if (stat(path, &st) || /* stat, not lstat */
130 !S_ISREG(st.st_mode) ||
131 !(st.st_mode & S_IXUSR))
132 continue;
134 entlen = strlen(de->d_name);
136 if (longest < entlen)
137 longest = entlen;
139 add_cmdname(de->d_name + 4, entlen-4);
141 closedir(dir);
143 printf("git commands available in '%s'\n", exec_path);
144 printf("----------------------------");
145 mput_char('-', strlen(exec_path));
146 putchar('\n');
147 pretty_print_string_list(cmdname, longest - 4);
148 putchar('\n');
151 #ifdef __GNUC__
152 static void usage(const char *exec_path, const char *fmt, ...)
153 __attribute__((__format__(__printf__, 2, 3), __noreturn__));
154 #endif
155 static void usage(const char *exec_path, const char *fmt, ...)
157 if (fmt) {
158 va_list ap;
160 va_start(ap, fmt);
161 printf("git: ");
162 vprintf(fmt, ap);
163 va_end(ap);
164 putchar('\n');
166 else
167 puts(git_usage);
169 putchar('\n');
171 if(exec_path)
172 list_commands(exec_path, "git-*");
174 exit(1);
177 static void prepend_to_path(const char *dir, int len)
179 char *path, *old_path = getenv("PATH");
180 int path_len = len;
182 if (!old_path)
183 old_path = "/usr/local/bin:/usr/bin:/bin";
185 path_len = len + strlen(old_path) + 1;
187 path = malloc(path_len + 1);
188 path[path_len + 1] = '\0';
190 memcpy(path, dir, len);
191 path[len] = ':';
192 memcpy(path + len + 1, old_path, path_len - len);
194 setenv("PATH", path, 1);
197 static void show_man_page(char *git_cmd)
199 char *page;
201 if (!strncmp(git_cmd, "git", 3))
202 page = git_cmd;
203 else {
204 int page_len = strlen(git_cmd) + 4;
206 page = malloc(page_len + 1);
207 strcpy(page, "git-");
208 strcpy(page + 4, git_cmd);
209 page[page_len] = 0;
212 execlp("man", "man", page, NULL);
215 int main(int argc, char **argv, char **envp)
217 char git_command[PATH_MAX + 1];
218 char wd[PATH_MAX + 1];
219 int i, len, show_help = 0;
220 char *exec_path = getenv("GIT_EXEC_PATH");
222 getcwd(wd, PATH_MAX);
224 if (!exec_path)
225 exec_path = GIT_EXEC_PATH;
227 for (i = 1; i < argc; i++) {
228 char *arg = argv[i];
230 if (strncmp(arg, "--", 2))
231 break;
233 arg += 2;
235 if (!strncmp(arg, "exec-path", 9)) {
236 arg += 9;
237 if (*arg == '=')
238 exec_path = arg + 1;
239 else {
240 puts(exec_path);
241 exit(0);
244 else if (!strcmp(arg, "version")) {
245 printf("git version %s\n", GIT_VERSION);
246 exit(0);
248 else if (!strcmp(arg, "help"))
249 show_help = 1;
250 else if (!show_help)
251 usage(NULL, NULL);
254 if (i >= argc || show_help) {
255 if (i >= argc)
256 usage(exec_path, NULL);
258 show_man_page(argv[i]);
261 if (*exec_path != '/') {
262 if (!getcwd(git_command, sizeof(git_command))) {
263 fprintf(stderr,
264 "git: cannot determine current directory");
265 exit(1);
267 len = strlen(git_command);
269 /* Trivial cleanup */
270 while (!strncmp(exec_path, "./", 2)) {
271 exec_path += 2;
272 while (*exec_path == '/')
273 *exec_path++;
275 snprintf(git_command + len, sizeof(git_command) - len,
276 "/%s", exec_path);
278 else
279 strcpy(git_command, exec_path);
280 len = strlen(git_command);
281 prepend_to_path(git_command, len);
283 strncat(&git_command[len], "/git-", sizeof(git_command) - len);
284 len += 5;
285 strncat(&git_command[len], argv[i], sizeof(git_command) - len);
287 if (access(git_command, X_OK))
288 usage(exec_path, "'%s' is not a git-command", argv[i]);
290 /* execve() can only ever return if it fails */
291 execve(git_command, &argv[i], envp);
292 printf("Failed to run command '%s': %s\n", git_command, strerror(errno));
294 return 1;