+#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>
+
+#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;
+
+ 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+1);
+ 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;
+ int space = longest + 1; /* min 1 SP between words */
+ int max_cols = term_columns() - 1; /* don't print *on* the edge */
+ int i;
+
+ if (space < max_cols)
+ cols = max_cols / space;
+
+ qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare);
+
+ for (i = 0; i < cmdname_cnt; ) {
+ int c;
+ printf(" ");
+
+ for (c = cols; c && i < cmdname_cnt; i++) {
+ printf("%s", cmdname[i]->name);
+
+ if (--c)
+ mput_char(' ', space - cmdname[i]->len);
+ }
+ 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 (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 usage(const char *exec_path, const char *fmt, ...)
+ __attribute__((__format__(__printf__, 2, 3), __noreturn__));
+#endif
+static void 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);
+ path[path_len + 1] = '\0';
+
+ 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)
+ usage(NULL, NULL);
+ }
+
+ if (i >= argc || show_help) {
+ if (i >= argc)
+ 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");
+ 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);
+
+ strncat(&git_command[len], "/git-", sizeof(git_command) - len);
+ len += 5;
+ strncat(&git_command[len], argv[i], sizeof(git_command) - len);
+
+ if (access(git_command, X_OK))
+ usage(exec_path, "'%s' is not a git-command", argv[i]);
+
+ /* execve() can only ever return if it fails */
+ execve(git_command, &argv[i], envp);
+ printf("Failed to run command '%s': %s\n", git_command, strerror(errno));
+
+ return 1;
+}
projects / git.git / commitdiff