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