Andrew's git - gitweb.git/blob

   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>
  11#include "git-compat-util.h"
  12#include "exec_cmd.h"
  13
  14#include "builtin.h"
  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)
  22                old_path = "/usr/local/bin:/usr/bin:/bin";
  23
  24        path_len = len + strlen(old_path) + 1;
  25
  26        path = malloc(path_len + 1);
  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
  35const char git_version_string[] = GIT_VERSION;
  36
  37static void handle_internal_command(int argc, const char **argv, char **envp)
  38{
  39        const char *cmd = argv[0];
  40        static struct cmd_struct {
  41                const char *cmd;
  42                int (*fn)(int, const char **, char **);
  43        } commands[] = {
  44                { "version", cmd_version },
  45                { "help", cmd_help },
  46                { "log", cmd_log },
  47                { "whatchanged", cmd_whatchanged },
  48                { "show", cmd_show },
  49                { "push", cmd_push },
  50                { "fmt-patch", cmd_format_patch },
  51                { "count-objects", cmd_count_objects },
  52                { "diff", cmd_diff },
  53                { "grep", cmd_grep },
  54                { "add", cmd_add },
  55        };
  56        int i;
  57
  58        /* Turn "git cmd --help" into "git help cmd" */
  59        if (argc > 1 && !strcmp(argv[1], "--help")) {
  60                argv[1] = argv[0];
  61                argv[0] = cmd = "help";
  62        }
  63
  64        for (i = 0; i < ARRAY_SIZE(commands); i++) {
  65                struct cmd_struct *p = commands+i;
  66                if (strcmp(p->cmd, cmd))
  67                        continue;
  68                exit(p->fn(argc, argv, envp));
  69        }
  70}
  71
  72int main(int argc, const char **argv, char **envp)
  73{
  74        const char *cmd = argv[0];
  75        char *slash = strrchr(cmd, '/');
  76        char git_command[PATH_MAX + 1];
  77        const char *exec_path = NULL;
  78
  79        /*
  80         * Take the basename of argv[0] as the command
  81         * name, and the dirname as the default exec_path
  82         * if it's an absolute path and we don't have
  83         * anything better.
  84         */
  85        if (slash) {
  86                *slash++ = 0;
  87                if (*cmd == '/')
  88                        exec_path = cmd;
  89                cmd = slash;
  90        }
  91
  92        /*
  93         * "git-xxxx" is the same as "git xxxx", but we obviously:
  94         *
  95         *  - cannot take flags in between the "git" and the "xxxx".
  96         *  - cannot execute it externally (since it would just do
  97         *    the same thing over again)
  98         *
  99         * So we just directly call the internal command handler, and
 100         * die if that one cannot handle it.
 101         */
 102        if (!strncmp(cmd, "git-", 4)) {
 103                cmd += 4;
 104                argv[0] = cmd;
 105                handle_internal_command(argc, argv, envp);
 106                die("cannot handle %s internally", cmd);
 107        }
 108
 109        /* Default command: "help" */
 110        cmd = "help";
 111
 112        /* Look for flags.. */
 113        while (argc > 1) {
 114                cmd = *++argv;
 115                argc--;
 116
 117                if (strncmp(cmd, "--", 2))
 118                        break;
 119
 120                cmd += 2;
 121
 122                /*
 123                 * For legacy reasons, the "version" and "help"
 124                 * commands can be written with "--" prepended
 125                 * to make them look like flags.
 126                 */
 127                if (!strcmp(cmd, "help"))
 128                        break;
 129                if (!strcmp(cmd, "version"))
 130                        break;
 131
 132                /*
 133                 * Check remaining flags (which by now must be
 134                 * "--exec-path", but maybe we will accept
 135                 * other arguments some day)
 136                 */
 137                if (!strncmp(cmd, "exec-path", 9)) {
 138                        cmd += 9;
 139                        if (*cmd == '=') {
 140                                git_set_exec_path(cmd + 1);
 141                                continue;
 142                        }
 143                        puts(git_exec_path());
 144                        exit(0);
 145                }
 146                cmd_usage(0, NULL, NULL);
 147        }
 148        argv[0] = cmd;
 149
 150        /*
 151         * We search for git commands in the following order:
 152         *  - git_exec_path()
 153         *  - the path of the "git" command if we could find it
 154         *    in $0
 155         *  - the regular PATH.
 156         */
 157        if (exec_path)
 158                prepend_to_path(exec_path, strlen(exec_path));
 159        exec_path = git_exec_path();
 160        prepend_to_path(exec_path, strlen(exec_path));
 161
 162        /* See if it's an internal command */
 163        handle_internal_command(argc, argv, envp);
 164
 165        /* .. then try the external ones */
 166        execv_git_cmd(argv);
 167
 168        if (errno == ENOENT)
 169                cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
 170
 171        fprintf(stderr, "Failed to run command '%s': %s\n",
 172                git_command, strerror(errno));
 173
 174        return 1;
 175}