[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"

#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);
}

int main(int argc, char **argv, char **envp)
{
	char git_command[PATH_MAX + 1];
	char wd[PATH_MAX + 1];
	int i, len, show_help = 0;
	char *exec_path = getenv("GIT_EXEC_PATH");

	getcwd(wd, PATH_MAX);

	if (!exec_path)
		exec_path = GIT_EXEC_PATH;

	for (i = 1; i < argc; i++) {
		char *arg = argv[i];

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

		arg += 2;

		if (!strncmp(arg, "exec-path", 9)) {
			arg += 9;
			if (*arg == '=')
				exec_path = arg + 1;
			else {
				puts(exec_path);
				exit(0);
			}
		}
		else if (!strcmp(arg, "version")) {
			printf("git version %s\n", GIT_VERSION);
			exit(0);
		}
		else if (!strcmp(arg, "help"))
			show_help = 1;
		else if (!show_help)
			cmd_usage(NULL, NULL);
	}

	if (i >= argc || show_help) {
		if (i >= argc)
			cmd_usage(exec_path, NULL);

		show_man_page(argv[i]);
	}

	if (*exec_path != '/') {
		if (!getcwd(git_command, sizeof(git_command))) {
			fprintf(stderr,
				"git: cannot determine current directory\n");
			exit(1);
		}
		len = strlen(git_command);

		/* Trivial cleanup */
		while (!strncmp(exec_path, "./", 2)) {
			exec_path += 2;
			while (*exec_path == '/')
				exec_path++;
		}
		snprintf(git_command + len, sizeof(git_command) - len,
			 "/%s", exec_path);
	}
	else
		strcpy(git_command, exec_path);
	len = strlen(git_command);
	prepend_to_path(git_command, len);

	len += snprintf(git_command + len, sizeof(git_command) - len,
			"/git-%s", argv[i]);
	if (sizeof(git_command) <= len) {
		fprintf(stderr, "git: command name given is too long.\n");
		exit(1);
	}

	/* execve() can only ever return if it fails */
	execve(git_command, &argv[i], envp);

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

	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"
8e49d503 AE	13
	14	#ifndef PATH_MAX
	15	# define PATH_MAX 4096
	16	#endif
	17
	18	static const char git_usage[] =
	19	"Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]";
	20
8e49d503 AE	21	/* most gui terms set COLUMNS (although some don't export it) */
	22	static int term_columns(void)
	23	{
	24	char *col_string = getenv("COLUMNS");
	25	int n_cols = 0;
	26
	27	if (col_string && (n_cols = atoi(col_string)) > 0)
	28	return n_cols;
	29
ea77e675 LT	30	#ifdef TIOCGWINSZ
	31	{
	32	struct winsize ws;
	33	if (!ioctl(1, TIOCGWINSZ, &ws)) {
	34	if (ws.ws_col)
	35	return ws.ws_col;
	36	}
	37	}
	38	#endif
	39
8e49d503 AE	40	return 80;
	41	}
	42
7dbc2c04 JH	43	static void oom(void)
	44	{
	45	fprintf(stderr, "git: out of memory\n");
	46	exit(1);
	47	}
	48
8e49d503 AE	49	static inline void mput_char(char c, unsigned int num)
	50	{
	51	while(num--)
	52	putchar(c);
	53	}
	54
7dbc2c04 JH	55	static struct cmdname {
	56	size_t len;
	57	char name[1];
	58	} **cmdname;
	59	static int cmdname_alloc, cmdname_cnt;
	60
	61	static void add_cmdname(const char *name, int len)
	62	{
	63	struct cmdname *ent;
	64	if (cmdname_alloc <= cmdname_cnt) {
	65	cmdname_alloc = cmdname_alloc + 200;
	66	cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname));
	67	if (!cmdname)
	68	oom();
	69	}
	70	ent = malloc(sizeof(*ent) + len);
	71	if (!ent)
	72	oom();
	73	ent->len = len;
f9039f30 JH	74	memcpy(ent->name, name, len);
f9039f30 JH	75	ent->name[len] = 0;
7dbc2c04 JH	76	cmdname[cmdname_cnt++] = ent;
	77	}
	78
	79	static int cmdname_compare(const void a_, const void b_)
	80	{
	81	struct cmdname a = (struct cmdname **)a_;
	82	struct cmdname b = (struct cmdname **)b_;
	83	return strcmp(a->name, b->name);
	84	}
	85
	86	static void pretty_print_string_list(struct cmdname **cmdname, int longest)
8e49d503	87	{
112d0baf	88	int cols = 1, rows;
8e49d503 AE	89	int space = longest + 1; /* min 1 SP between words */
8e49d503 AE	90	int max_cols = term_columns() - 1; /* don't print on the edge */
112d0baf	91	int i, j;
8e49d503 AE	92
	93	if (space < max_cols)
	94	cols = max_cols / space;
112d0baf	95	rows = (cmdname_cnt + cols - 1) / cols;
8e49d503	96
7dbc2c04 JH	97	qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
7dbc2c04 JH	98
112d0baf	99	for (i = 0; i < rows; i++) {
8e49d503 AE	100	printf(" ");
8e49d503 AE	101
112d0baf LT	102	for (j = 0; j < cols; j++) {
	103	int n = j * rows + i;
	104	int size = space;
	105	if (n >= cmdname_cnt)
	106	break;
	107	if (j == cols-1 \|\| n + rows >= cmdname_cnt)
	108	size = 1;
	109	printf("%-*s", size, cmdname[n]->name);
8e49d503 AE	110	}
	111	putchar('\n');
	112	}
	113	}
	114
	115	static void list_commands(const char exec_path, const char pattern)
	116	{
7dbc2c04 JH	117	unsigned int longest = 0;
	118	char path[PATH_MAX];
	119	int dirlen;
	120	DIR *dir = opendir(exec_path);
	121	struct dirent *de;
	122
	123	if (!dir) {
	124	fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno));
8e49d503 AE	125	exit(1);
	126	}
	127
7dbc2c04 JH	128	dirlen = strlen(exec_path);
	129	if (PATH_MAX - 20 < dirlen) {
	130	fprintf(stderr, "git: insanely long exec-path '%s'\n",
	131	exec_path);
8e49d503 AE	132	exit(1);
	133	}
	134
7dbc2c04 JH	135	memcpy(path, exec_path, dirlen);
	136	path[dirlen++] = '/';
	137
	138	while ((de = readdir(dir)) != NULL) {
	139	struct stat st;
	140	int entlen;
8e49d503	141
7dbc2c04 JH	142	if (strncmp(de->d_name, "git-", 4))
	143	continue;
	144	strcpy(path+dirlen, de->d_name);
	145	if (stat(path, &st) \|\| /* stat, not lstat */
	146	!S_ISREG(st.st_mode) \|\|
	147	!(st.st_mode & S_IXUSR))
8e49d503 AE	148	continue;
8e49d503 AE	149
7dbc2c04	150	entlen = strlen(de->d_name);
f9039f30 JH	151	if (4 < entlen && !strcmp(de->d_name + entlen - 4, ".exe"))
f9039f30 JH	152	entlen -= 4;
8e49d503	153
7dbc2c04 JH	154	if (longest < entlen)
	155	longest = entlen;
	156
	157	add_cmdname(de->d_name + 4, entlen-4);
8e49d503	158	}
7dbc2c04	159	closedir(dir);
8e49d503 AE	160
	161	printf("git commands available in '%s'\n", exec_path);
	162	printf("----------------------------");
	163	mput_char('-', strlen(exec_path));
	164	putchar('\n');
7dbc2c04	165	pretty_print_string_list(cmdname, longest - 4);
8e49d503 AE	166	putchar('\n');
	167	}
	168
	169	#ifdef __GNUC__
4050c0df	170	static void cmd_usage(const char exec_path, const char fmt, ...)
8e49d503 AE	171	__attribute__((__format__(__printf__, 2, 3), __noreturn__));
8e49d503 AE	172	#endif
4050c0df	173	static void cmd_usage(const char exec_path, const char fmt, ...)
8e49d503 AE	174	{
	175	if (fmt) {
	176	va_list ap;
	177
	178	va_start(ap, fmt);
	179	printf("git: ");
	180	vprintf(fmt, ap);
	181	va_end(ap);
	182	putchar('\n');
	183	}
	184	else
	185	puts(git_usage);
	186
	187	putchar('\n');
	188
	189	if(exec_path)
	190	list_commands(exec_path, "git-*");
	191
	192	exit(1);
	193	}
	194
	195	static void prepend_to_path(const char *dir, int len)
	196	{
	197	char path, old_path = getenv("PATH");
	198	int path_len = len;
	199
	200	if (!old_path)
7dbc2c04	201	old_path = "/usr/local/bin:/usr/bin:/bin";
8e49d503 AE	202
	203	path_len = len + strlen(old_path) + 1;
	204
	205	path = malloc(path_len + 1);
8e49d503 AE	206
	207	memcpy(path, dir, len);
	208	path[len] = ':';
	209	memcpy(path + len + 1, old_path, path_len - len);
	210
	211	setenv("PATH", path, 1);
	212	}
	213
97fc6c5f AE	214	static void show_man_page(char *git_cmd)
	215	{
	216	char *page;
	217
	218	if (!strncmp(git_cmd, "git", 3))
	219	page = git_cmd;
	220	else {
	221	int page_len = strlen(git_cmd) + 4;
	222
	223	page = malloc(page_len + 1);
	224	strcpy(page, "git-");
	225	strcpy(page + 4, git_cmd);
	226	page[page_len] = 0;
	227	}
	228
7dbc2c04	229	execlp("man", "man", page, NULL);
97fc6c5f AE	230	}
97fc6c5f AE	231
8e49d503 AE	232	int main(int argc, char argv, char envp)
	233	{
	234	char git_command[PATH_MAX + 1];
	235	char wd[PATH_MAX + 1];
	236	int i, len, show_help = 0;
	237	char *exec_path = getenv("GIT_EXEC_PATH");
	238
	239	getcwd(wd, PATH_MAX);
	240
	241	if (!exec_path)
	242	exec_path = GIT_EXEC_PATH;
	243
	244	for (i = 1; i < argc; i++) {
	245	char *arg = argv[i];
	246
	247	if (strncmp(arg, "--", 2))
	248	break;
	249
	250	arg += 2;
	251
	252	if (!strncmp(arg, "exec-path", 9)) {
	253	arg += 9;
	254	if (*arg == '=')
	255	exec_path = arg + 1;
	256	else {
	257	puts(exec_path);
	258	exit(0);
	259	}
	260	}
	261	else if (!strcmp(arg, "version")) {
	262	printf("git version %s\n", GIT_VERSION);
	263	exit(0);
	264	}
	265	else if (!strcmp(arg, "help"))
	266	show_help = 1;
	267	else if (!show_help)
4050c0df	268	cmd_usage(NULL, NULL);
8e49d503 AE	269	}
8e49d503 AE	270
97fc6c5f AE	271	if (i >= argc \|\| show_help) {
97fc6c5f AE	272	if (i >= argc)
4050c0df	273	cmd_usage(exec_path, NULL);
97fc6c5f AE	274
	275	show_man_page(argv[i]);
	276	}
8e49d503	277
7dbc2c04 JH	278	if (*exec_path != '/') {
	279	if (!getcwd(git_command, sizeof(git_command))) {
	280	fprintf(stderr,
7246ed43	281	"git: cannot determine current directory\n");
7dbc2c04 JH	282	exit(1);
	283	}
	284	len = strlen(git_command);
8e49d503	285
7dbc2c04 JH	286	/* Trivial cleanup */
	287	while (!strncmp(exec_path, "./", 2)) {
	288	exec_path += 2;
	289	while (*exec_path == '/')
874fbc33	290	exec_path++;
7dbc2c04 JH	291	}
	292	snprintf(git_command + len, sizeof(git_command) - len,
	293	"/%s", exec_path);
	294	}
	295	else
	296	strcpy(git_command, exec_path);
8e49d503 AE	297	len = strlen(git_command);
	298	prepend_to_path(git_command, len);
	299
10b15b86 AR	300	len += snprintf(git_command + len, sizeof(git_command) - len,
	301	"/git-%s", argv[i]);
	302	if (sizeof(git_command) <= len) {
b270c634	303	fprintf(stderr, "git: command name given is too long.\n");
10b15b86 AR	304	exit(1);
10b15b86 AR	305	}
8e49d503 AE	306
	307	/* execve() can only ever return if it fails */
	308	execve(git_command, &argv[i], envp);
10b15b86 AR	309
10b15b86 AR	310	if (errno == ENOENT)
4050c0df	311	cmd_usage(exec_path, "'%s' is not a git-command", argv[i]);
10b15b86 AR	312
	313	fprintf(stderr, "Failed to run command '%s': %s\n",
	314	git_command, strerror(errno));
8e49d503 AE	315
	316	return 1;
	317	}