[thirdparty/git.git] / git.c

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <stdarg.h>
#include <sys/ioctl.h>
#include "git-compat-util.h"
#include "exec_cmd.h"

#ifndef PATH_MAX
# define PATH_MAX 4096
#endif

static const char git_usage[] =
	"Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]";

/* most gui terms set COLUMNS (although some don't export it) */
static int term_columns(void)
{
	char *col_string = getenv("COLUMNS");
	int n_cols = 0;

	if (col_string && (n_cols = atoi(col_string)) > 0)
		return n_cols;

#ifdef TIOCGWINSZ
	{
		struct winsize ws;
		if (!ioctl(1, TIOCGWINSZ, &ws)) {
			if (ws.ws_col)
				return ws.ws_col;
		}
	}
#endif

	return 80;
}

static void oom(void)
{
	fprintf(stderr, "git: out of memory\n");
	exit(1);
}

static inline void mput_char(char c, unsigned int num)
{
	while(num--)
		putchar(c);
}

static struct cmdname {
	size_t len;
	char name[1];
} **cmdname;
static int cmdname_alloc, cmdname_cnt;

static void add_cmdname(const char *name, int len)
{
	struct cmdname *ent;
	if (cmdname_alloc <= cmdname_cnt) {
		cmdname_alloc = cmdname_alloc + 200;
		cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
		if (!cmdname)
			oom();
	}
	ent = malloc(sizeof(*ent) + len);
	if (!ent)
		oom();
	ent->len = len;
	memcpy(ent->name, name, len);
	ent->name[len] = 0;
	cmdname[cmdname_cnt++] = ent;
}

static int cmdname_compare(const void *a_, const void *b_)
{
	struct cmdname *a = *(struct cmdname **)a_;
	struct cmdname *b = *(struct cmdname **)b_;
	return strcmp(a->name, b->name);
}

static void pretty_print_string_list(struct cmdname **cmdname, int longest)
{
	int cols = 1, rows;
	int space = longest + 1; /* min 1 SP between words */
	int max_cols = term_columns() - 1; /* don't print *on* the edge */
	int i, j;

	if (space < max_cols)
		cols = max_cols / space;
	rows = (cmdname_cnt + cols - 1) / cols;

	qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);

	for (i = 0; i < rows; i++) {
		printf("  ");

		for (j = 0; j < cols; j++) {
			int n = j * rows + i;
			int size = space;
			if (n >= cmdname_cnt)
				break;
			if (j == cols-1 || n + rows >= cmdname_cnt)
				size = 1;
			printf("%-*s", size, cmdname[n]->name);
		}
		putchar('\n');
	}
}

static void list_commands(const char *exec_path, const char *pattern)
{
	unsigned int longest = 0;
	char path[PATH_MAX];
	int dirlen;
	DIR *dir = opendir(exec_path);
	struct dirent *de;

	if (!dir) {
		fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
		exit(1);
	}

	dirlen = strlen(exec_path);
	if (PATH_MAX - 20 < dirlen) {
		fprintf(stderr, "git: insanely long exec-path '%s'\n",
			exec_path);
		exit(1);
	}

	memcpy(path, exec_path, dirlen);
	path[dirlen++] = '/';

	while ((de = readdir(dir)) != NULL) {
		struct stat st;
		int entlen;

		if (strncmp(de->d_name, "git-", 4))
			continue;
		strcpy(path+dirlen, de->d_name);
		if (stat(path, &st) || /* stat, not lstat */
		    !S_ISREG(st.st_mode) ||
		    !(st.st_mode & S_IXUSR))
			continue;

		entlen = strlen(de->d_name);
		if (4 < entlen && !strcmp(de->d_name + entlen - 4, ".exe"))
			entlen -= 4;

		if (longest < entlen)
			longest = entlen;

		add_cmdname(de->d_name + 4, entlen-4);
	}
	closedir(dir);

	printf("git commands available in '%s'\n", exec_path);
	printf("----------------------------");
	mput_char('-', strlen(exec_path));
	putchar('\n');
	pretty_print_string_list(cmdname, longest - 4);
	putchar('\n');
}

#ifdef __GNUC__
static void cmd_usage(const char *exec_path, const char *fmt, ...)
	__attribute__((__format__(__printf__, 2, 3), __noreturn__));
#endif
static void cmd_usage(const char *exec_path, const char *fmt, ...)
{
	if (fmt) {
		va_list ap;

		va_start(ap, fmt);
		printf("git: ");
		vprintf(fmt, ap);
		va_end(ap);
		putchar('\n');
	}
	else
		puts(git_usage);

	putchar('\n');

	if(exec_path)
		list_commands(exec_path, "git-*");

	exit(1);
}

static void prepend_to_path(const char *dir, int len)
{
	char *path, *old_path = getenv("PATH");
	int path_len = len;

	if (!old_path)
		old_path = "/usr/local/bin:/usr/bin:/bin";

	path_len = len + strlen(old_path) + 1;

	path = malloc(path_len + 1);

	memcpy(path, dir, len);
	path[len] = ':';
	memcpy(path + len + 1, old_path, path_len - len);

	setenv("PATH", path, 1);
}

static void show_man_page(char *git_cmd)
{
	char *page;

	if (!strncmp(git_cmd, "git", 3))
		page = git_cmd;
	else {
		int page_len = strlen(git_cmd) + 4;

		page = malloc(page_len + 1);
		strcpy(page, "git-");
		strcpy(page + 4, git_cmd);
		page[page_len] = 0;
	}

	execlp("man", "man", page, NULL);
}

static int cmd_version(int argc, char **argv, char **envp)
{
	printf("git version %s\n", GIT_VERSION);
	return 0;
}

static int cmd_help(int argc, char **argv, char **envp)
{
	char *help_cmd = argv[1];
	if (!help_cmd)
		cmd_usage(git_exec_path(), NULL);
	show_man_page(help_cmd);
	return 0;
}

#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))

static void handle_internal_command(int argc, char **argv, char **envp)
{
	const char *cmd = argv[0];
	static struct cmd_struct {
		const char *cmd;
		int (*fn)(int, char **, char **);
	} commands[] = {
		{ "version", cmd_version },
		{ "help", cmd_help },
	};
	int i;

	for (i = 0; i < ARRAY_SIZE(commands); i++) {
		struct cmd_struct *p = commands+i;
		if (strcmp(p->cmd, cmd))
			continue;
		exit(p->fn(argc, argv, envp));
	}
}

int main(int argc, char **argv, char **envp)
{
	char *cmd = argv[0];
	char *slash = strrchr(cmd, '/');
	char git_command[PATH_MAX + 1];
	const char *exec_path = NULL;

	/*
	 * Take the basename of argv[0] as the command
	 * name, and the dirname as the default exec_path
	 * if it's an absolute path and we don't have
	 * anything better.
	 */
	if (slash) {
		*slash++ = 0;
		if (*cmd == '/')
			exec_path = cmd;
		cmd = slash;
	}

	/*
	 * "git-xxxx" is the same as "git xxxx", but we obviously:
	 *
	 *  - cannot take flags in between the "git" and the "xxxx".
	 *  - cannot execute it externally (since it would just do
	 *    the same thing over again)
	 *
	 * So we just directly call the internal command handler, and
	 * die if that one cannot handle it.
	 */
	if (!strncmp(cmd, "git-", 4)) {
		cmd += 4;
		argv[0] = cmd;
		handle_internal_command(argc, argv, envp);
		die("cannot handle %s internally", cmd);
	}

	/* Default command: "help" */
	cmd = "help";

	/* Look for flags.. */
	while (argc > 1) {
		cmd = *++argv;
		argc--;

		if (strncmp(cmd, "--", 2))
			break;

		cmd += 2;

		/*
		 * For legacy reasons, the "version" and "help"
		 * commands can be written with "--" prepended
		 * to make them look like flags.
		 */
		if (!strcmp(cmd, "help"))
			break;
		if (!strcmp(cmd, "version"))
			break;

		/*
		 * Check remaining flags (which by now must be
		 * "--exec-path", but maybe we will accept
		 * other arguments some day)
		 */
		if (!strncmp(cmd, "exec-path", 9)) {
			cmd += 9;
			if (*cmd == '=') {
				git_set_exec_path(cmd + 1);
				continue;
			}
			puts(git_exec_path());
			exit(0);
		}
		cmd_usage(NULL, NULL);
	}
	argv[0] = cmd;

	/*
	 * We search for git commands in the following order:
	 *  - git_exec_path()
	 *  - the path of the "git" command if we could find it
	 *    in $0
	 *  - the regular PATH.
	 */
	if (exec_path)
		prepend_to_path(exec_path, strlen(exec_path));
	exec_path = git_exec_path();
	prepend_to_path(exec_path, strlen(exec_path));

	/* See if it's an internal command */
	handle_internal_command(argc, argv, envp);

	/* .. then try the external ones */
	execv_git_cmd(argv);

	if (errno == ENOENT)
		cmd_usage(exec_path, "'%s' is not a git-command", cmd);

	fprintf(stderr, "Failed to run command '%s': %s\n",
		git_command, strerror(errno));

	return 1;
}
Commit	Line	Data
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>
ea77e675	11	#include <sys/ioctl.h>
4050c0df	12	#include "git-compat-util.h"
77cb17e9	13	#include "exec_cmd.h"
8e49d503 AE	14
	15	#ifndef PATH_MAX
	16	# define PATH_MAX 4096
	17	#endif
	18
	19	static const char git_usage[] =
	20	"Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]";
	21
8e49d503 AE	22	/* most gui terms set COLUMNS (although some don't export it) */
	23	static int term_columns(void)
	24	{
	25	char *col_string = getenv("COLUMNS");
	26	int n_cols = 0;
	27
	28	if (col_string && (n_cols = atoi(col_string)) > 0)
	29	return n_cols;
	30
ea77e675 LT	31	#ifdef TIOCGWINSZ
	32	{
	33	struct winsize ws;
	34	if (!ioctl(1, TIOCGWINSZ, &ws)) {
	35	if (ws.ws_col)
	36	return ws.ws_col;
	37	}
	38	}
	39	#endif
	40
8e49d503 AE	41	return 80;
	42	}
	43
7dbc2c04 JH	44	static void oom(void)
	45	{
	46	fprintf(stderr, "git: out of memory\n");
	47	exit(1);
	48	}
	49
8e49d503 AE	50	static inline void mput_char(char c, unsigned int num)
	51	{
	52	while(num--)
	53	putchar(c);
	54	}
	55
7dbc2c04 JH	56	static struct cmdname {
	57	size_t len;
	58	char name[1];
	59	} **cmdname;
	60	static int cmdname_alloc, cmdname_cnt;
	61
	62	static void add_cmdname(const char *name, int len)
	63	{
	64	struct cmdname *ent;
	65	if (cmdname_alloc <= cmdname_cnt) {
	66	cmdname_alloc = cmdname_alloc + 200;
	67	cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
	68	if (!cmdname)
	69	oom();
	70	}
	71	ent = malloc(sizeof(*ent) + len);
	72	if (!ent)
	73	oom();
	74	ent->len = len;
f9039f30 JH	75	memcpy(ent->name, name, len);
f9039f30 JH	76	ent->name[len] = 0;
7dbc2c04 JH	77	cmdname[cmdname_cnt++] = ent;
	78	}
	79
	80	static int cmdname_compare(const void a_, const void b_)
	81	{
	82	struct cmdname a = (struct cmdname **)a_;
	83	struct cmdname b = (struct cmdname **)b_;
	84	return strcmp(a->name, b->name);
	85	}
	86
	87	static void pretty_print_string_list(struct cmdname **cmdname, int longest)
8e49d503	88	{
112d0baf	89	int cols = 1, rows;
8e49d503 AE	90	int space = longest + 1; /* min 1 SP between words */
8e49d503 AE	91	int max_cols = term_columns() - 1; /* don't print on the edge */
112d0baf	92	int i, j;
8e49d503 AE	93
	94	if (space < max_cols)
	95	cols = max_cols / space;
112d0baf	96	rows = (cmdname_cnt + cols - 1) / cols;
8e49d503	97
7dbc2c04 JH	98	qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
7dbc2c04 JH	99
112d0baf	100	for (i = 0; i < rows; i++) {
8e49d503 AE	101	printf(" ");
8e49d503 AE	102
112d0baf LT	103	for (j = 0; j < cols; j++) {
	104	int n = j * rows + i;
	105	int size = space;
	106	if (n >= cmdname_cnt)
	107	break;
	108	if (j == cols-1 \|\| n + rows >= cmdname_cnt)
	109	size = 1;
	110	printf("%-*s", size, cmdname[n]->name);
8e49d503 AE	111	}
	112	putchar('\n');
	113	}
	114	}
	115
	116	static void list_commands(const char exec_path, const char pattern)
	117	{
7dbc2c04 JH	118	unsigned int longest = 0;
	119	char path[PATH_MAX];
	120	int dirlen;
	121	DIR *dir = opendir(exec_path);
	122	struct dirent *de;
	123
	124	if (!dir) {
	125	fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
8e49d503 AE	126	exit(1);
	127	}
	128
7dbc2c04 JH	129	dirlen = strlen(exec_path);
	130	if (PATH_MAX - 20 < dirlen) {
	131	fprintf(stderr, "git: insanely long exec-path '%s'\n",
	132	exec_path);
8e49d503 AE	133	exit(1);
	134	}
	135
7dbc2c04 JH	136	memcpy(path, exec_path, dirlen);
	137	path[dirlen++] = '/';
	138
	139	while ((de = readdir(dir)) != NULL) {
	140	struct stat st;
	141	int entlen;
8e49d503	142
7dbc2c04 JH	143	if (strncmp(de->d_name, "git-", 4))
	144	continue;
	145	strcpy(path+dirlen, de->d_name);
	146	if (stat(path, &st) \|\| /* stat, not lstat */
	147	!S_ISREG(st.st_mode) \|\|
	148	!(st.st_mode & S_IXUSR))
8e49d503 AE	149	continue;
8e49d503 AE	150
7dbc2c04	151	entlen = strlen(de->d_name);
f9039f30 JH	152	if (4 < entlen && !strcmp(de->d_name + entlen - 4, ".exe"))
f9039f30 JH	153	entlen -= 4;
8e49d503	154
7dbc2c04 JH	155	if (longest < entlen)
	156	longest = entlen;
	157
	158	add_cmdname(de->d_name + 4, entlen-4);
8e49d503	159	}
7dbc2c04	160	closedir(dir);
8e49d503 AE	161
	162	printf("git commands available in '%s'\n", exec_path);
	163	printf("----------------------------");
	164	mput_char('-', strlen(exec_path));
	165	putchar('\n');
7dbc2c04	166	pretty_print_string_list(cmdname, longest - 4);
8e49d503 AE	167	putchar('\n');
	168	}
	169
	170	#ifdef __GNUC__
4050c0df	171	static void cmd_usage(const char exec_path, const char fmt, ...)
8e49d503 AE	172	__attribute__((__format__(__printf__, 2, 3), __noreturn__));
8e49d503 AE	173	#endif
4050c0df	174	static void cmd_usage(const char exec_path, const char fmt, ...)
8e49d503 AE	175	{
	176	if (fmt) {
	177	va_list ap;
	178
	179	va_start(ap, fmt);
	180	printf("git: ");
	181	vprintf(fmt, ap);
	182	va_end(ap);
	183	putchar('\n');
	184	}
	185	else
	186	puts(git_usage);
	187
	188	putchar('\n');
	189
	190	if(exec_path)
	191	list_commands(exec_path, "git-*");
	192
	193	exit(1);
	194	}
	195
	196	static void prepend_to_path(const char *dir, int len)
	197	{
	198	char path, old_path = getenv("PATH");
	199	int path_len = len;
	200
	201	if (!old_path)
7dbc2c04	202	old_path = "/usr/local/bin:/usr/bin:/bin";
8e49d503 AE	203
	204	path_len = len + strlen(old_path) + 1;
	205
	206	path = malloc(path_len + 1);
8e49d503 AE	207
	208	memcpy(path, dir, len);
	209	path[len] = ':';
	210	memcpy(path + len + 1, old_path, path_len - len);
	211
	212	setenv("PATH", path, 1);
	213	}
	214
97fc6c5f AE	215	static void show_man_page(char *git_cmd)
	216	{
	217	char *page;
	218
	219	if (!strncmp(git_cmd, "git", 3))
	220	page = git_cmd;
	221	else {
	222	int page_len = strlen(git_cmd) + 4;
	223
	224	page = malloc(page_len + 1);
	225	strcpy(page, "git-");
	226	strcpy(page + 4, git_cmd);
	227	page[page_len] = 0;
	228	}
	229
7dbc2c04	230	execlp("man", "man", page, NULL);
97fc6c5f AE	231	}
97fc6c5f AE	232
231af832 LT	233	static int cmd_version(int argc, char argv, char envp)
	234	{
	235	printf("git version %s\n", GIT_VERSION);
	236	return 0;
	237	}
	238
	239	static int cmd_help(int argc, char argv, char envp)
	240	{
	241	char *help_cmd = argv[1];
	242	if (!help_cmd)
	243	cmd_usage(git_exec_path(), NULL);
	244	show_man_page(help_cmd);
	245	return 0;
	246	}
	247
	248	#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
	249
	250	static void handle_internal_command(int argc, char argv, char envp)
	251	{
	252	const char *cmd = argv[0];
	253	static struct cmd_struct {
	254	const char *cmd;
	255	int (fn)(int, char , char *);
	256	} commands[] = {
	257	{ "version", cmd_version },
	258	{ "help", cmd_help },
	259	};
	260	int i;
	261
	262	for (i = 0; i < ARRAY_SIZE(commands); i++) {
	263	struct cmd_struct *p = commands+i;
	264	if (strcmp(p->cmd, cmd))
	265	continue;
	266	exit(p->fn(argc, argv, envp));
	267	}
	268	}
	269
8e49d503 AE	270	int main(int argc, char argv, char envp)
8e49d503 AE	271	{
231af832 LT	272	char *cmd = argv[0];
231af832 LT	273	char *slash = strrchr(cmd, '/');
8e49d503	274	char git_command[PATH_MAX + 1];
231af832 LT	275	const char *exec_path = NULL;
	276
	277	/*
	278	* Take the basename of argv[0] as the command
	279	* name, and the dirname as the default exec_path
	280	* if it's an absolute path and we don't have
	281	* anything better.
	282	*/
	283	if (slash) {
	284	*slash++ = 0;
	285	if (*cmd == '/')
	286	exec_path = cmd;
	287	cmd = slash;
	288	}
8e49d503	289
231af832 LT	290	/*
	291	* "git-xxxx" is the same as "git xxxx", but we obviously:
	292	*
	293	* - cannot take flags in between the "git" and the "xxxx".
	294	* - cannot execute it externally (since it would just do
	295	* the same thing over again)
	296	*
	297	* So we just directly call the internal command handler, and
	298	* die if that one cannot handle it.
	299	*/
	300	if (!strncmp(cmd, "git-", 4)) {
	301	cmd += 4;
	302	argv[0] = cmd;
	303	handle_internal_command(argc, argv, envp);
	304	die("cannot handle %s internally", cmd);
	305	}
8e49d503	306
231af832 LT	307	/* Default command: "help" */
231af832 LT	308	cmd = "help";
8e49d503	309
231af832 LT	310	/* Look for flags.. */
	311	while (argc > 1) {
	312	cmd = *++argv;
	313	argc--;
da6bf70e	314
231af832	315	if (strncmp(cmd, "--", 2))
8e49d503 AE	316	break;
8e49d503 AE	317
231af832 LT	318	cmd += 2;
	319
	320	/*
	321	* For legacy reasons, the "version" and "help"
	322	* commands can be written with "--" prepended
	323	* to make them look like flags.
	324	*/
	325	if (!strcmp(cmd, "help"))
	326	break;
	327	if (!strcmp(cmd, "version"))
	328	break;
8e49d503	329
231af832 LT	330	/*
	331	* Check remaining flags (which by now must be
	332	* "--exec-path", but maybe we will accept
	333	* other arguments some day)
	334	*/
	335	if (!strncmp(cmd, "exec-path", 9)) {
	336	cmd += 9;
	337	if (*cmd == '=') {
	338	git_set_exec_path(cmd + 1);
	339	continue;
8e49d503	340	}
231af832	341	puts(git_exec_path());
8e49d503 AE	342	exit(0);
8e49d503 AE	343	}
231af832	344	cmd_usage(NULL, NULL);
97fc6c5f	345	}
231af832 LT	346	argv[0] = cmd;
	347
	348	/*
	349	* We search for git commands in the following order:
	350	* - git_exec_path()
	351	* - the path of the "git" command if we could find it
	352	* in $0
	353	* - the regular PATH.
	354	*/
	355	if (exec_path)
	356	prepend_to_path(exec_path, strlen(exec_path));
77cb17e9 MO	357	exec_path = git_exec_path();
77cb17e9 MO	358	prepend_to_path(exec_path, strlen(exec_path));
8e49d503	359
231af832 LT	360	/* See if it's an internal command */
	361	handle_internal_command(argc, argv, envp);
	362
	363	/* .. then try the external ones */
	364	execv_git_cmd(argv);
10b15b86 AR	365
10b15b86 AR	366	if (errno == ENOENT)
231af832	367	cmd_usage(exec_path, "'%s' is not a git-command", cmd);
10b15b86 AR	368
	369	fprintf(stderr, "Failed to run command '%s': %s\n",
	370	git_command, strerror(errno));
8e49d503 AE	371
	372	return 1;
	373	}