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 <sys/ioctl.h>
  12#include "git-compat-util.h"
  13#include "exec_cmd.h"
  14
  15#include "builtin.h"
  16
  17static void prepend_to_path(const char *dir, int len)
  18{
  19        char *path, *old_path = getenv("PATH");
  20        int path_len = len;
  21
  22        if (!old_path)
  23                old_path = "/usr/local/bin:/usr/bin:/bin";
  24
  25        path_len = len + strlen(old_path) + 1;
  26
  27        path = malloc(path_len + 1);
  28
  29        memcpy(path, dir, len);
  30        path[len] = ':';
  31        memcpy(path + len + 1, old_path, path_len - len);
  32
  33        setenv("PATH", path, 1);
  34}
  35
  36const char git_version_string[] = GIT_VERSION;
  37
  38static void handle_internal_command(int argc, const char **argv, char **envp)
  39{
  40        const char *cmd = argv[0];
  41        static struct cmd_struct {
  42                const char *cmd;
  43                int (*fn)(int, const char **, char **);
  44        } commands[] = {
  45                { "version", cmd_version },
  46                { "help", cmd_help },
  47                { "log", cmd_log },
  48                { "whatchanged", cmd_whatchanged },
  49                { "show", cmd_show },
  50                { "fmt-patch", cmd_format_patch },
  51        };
  52        int i;
  53
  54        /* Turn "git cmd --help" into "git help cmd" */
  55        if (argc > 1 && !strcmp(argv[1], "--help")) {
  56                argv[1] = argv[0];
  57                argv[0] = cmd = "help";
  58        }
  59
  60        for (i = 0; i < ARRAY_SIZE(commands); i++) {
  61                struct cmd_struct *p = commands+i;
  62                if (strcmp(p->cmd, cmd))
  63                        continue;
  64                exit(p->fn(argc, argv, envp));
  65        }
  66}
  67
  68int main(int argc, const char **argv, char **envp)
  69{
  70        const char *cmd = argv[0];
  71        char *slash = strrchr(cmd, '/');
  72        char git_command[PATH_MAX + 1];
  73        const char *exec_path = NULL;
  74
  75        /*
  76         * Take the basename of argv[0] as the command
  77         * name, and the dirname as the default exec_path
  78         * if it's an absolute path and we don't have
  79         * anything better.
  80         */
  81        if (slash) {
  82                *slash++ = 0;
  83                if (*cmd == '/')
  84                        exec_path = cmd;
  85                cmd = slash;
  86        }
  87
  88        /*
  89         * "git-xxxx" is the same as "git xxxx", but we obviously:
  90         *
  91         *  - cannot take flags in between the "git" and the "xxxx".
  92         *  - cannot execute it externally (since it would just do
  93         *    the same thing over again)
  94         *
  95         * So we just directly call the internal command handler, and
  96         * die if that one cannot handle it.
  97         */
  98        if (!strncmp(cmd, "git-", 4)) {
  99                cmd += 4;
 100                argv[0] = cmd;
 101                handle_internal_command(argc, argv, envp);
 102                die("cannot handle %s internally", cmd);
 103        }
 104
 105        /* Default command: "help" */
 106        cmd = "help";
 107
 108        /* Look for flags.. */
 109        while (argc > 1) {
 110                cmd = *++argv;
 111                argc--;
 112
 113                if (strncmp(cmd, "--", 2))
 114                        break;
 115
 116                cmd += 2;
 117
 118                /*
 119                 * For legacy reasons, the "version" and "help"
 120                 * commands can be written with "--" prepended
 121                 * to make them look like flags.
 122                 */
 123                if (!strcmp(cmd, "help"))
 124                        break;
 125                if (!strcmp(cmd, "version"))
 126                        break;
 127
 128                /*
 129                 * Check remaining flags (which by now must be
 130                 * "--exec-path", but maybe we will accept
 131                 * other arguments some day)
 132                 */
 133                if (!strncmp(cmd, "exec-path", 9)) {
 134                        cmd += 9;
 135                        if (*cmd == '=') {
 136                                git_set_exec_path(cmd + 1);
 137                                continue;
 138                        }
 139                        puts(git_exec_path());
 140                        exit(0);
 141                }
 142                cmd_usage(0, NULL, NULL);
 143        }
 144        argv[0] = cmd;
 145
 146        /*
 147         * We search for git commands in the following order:
 148         *  - git_exec_path()
 149         *  - the path of the "git" command if we could find it
 150         *    in $0
 151         *  - the regular PATH.
 152         */
 153        if (exec_path)
 154                prepend_to_path(exec_path, strlen(exec_path));
 155        exec_path = git_exec_path();
 156        prepend_to_path(exec_path, strlen(exec_path));
 157
 158        /* See if it's an internal command */
 159        handle_internal_command(argc, argv, envp);
 160
 161        /* .. then try the external ones */
 162        execv_git_cmd(argv);
 163
 164        if (errno == ENOENT)
 165                cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
 166
 167        fprintf(stderr, "Failed to run command '%s': %s\n",
 168                git_command, strerror(errno));
 169
 170        return 1;
 171}