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#include "cache.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
  36static const char *alias_command;
  37static char *alias_string = NULL;
  38
  39static int git_alias_config(const char *var, const char *value)
  40{
  41        if (!strncmp(var, "alias.", 6) && !strcmp(var + 6, alias_command)) {
  42                alias_string = strdup(value);
  43        }
  44        return 0;
  45}
  46
  47static int split_cmdline(char *cmdline, const char ***argv)
  48{
  49        int src, dst, count = 0, size = 16;
  50        char quoted = 0;
  51
  52        *argv = malloc(sizeof(char*) * size);
  53
  54        /* split alias_string */
  55        (*argv)[count++] = cmdline;
  56        for (src = dst = 0; cmdline[src];) {
  57                char c = cmdline[src];
  58                if (!quoted && isspace(c)) {
  59                        cmdline[dst++] = 0;
  60                        while (cmdline[++src]
  61                                        && isspace(cmdline[src]))
  62                                ; /* skip */
  63                        if (count >= size) {
  64                                size += 16;
  65                                *argv = realloc(*argv, sizeof(char*) * size);
  66                        }
  67                        (*argv)[count++] = cmdline + dst;
  68                } else if(!quoted && (c == '\'' || c == '"')) {
  69                        quoted = c;
  70                        src++;
  71                } else if (c == quoted) {
  72                        quoted = 0;
  73                        src++;
  74                } else {
  75                        if (c == '\\' && quoted != '\'') {
  76                                src++;
  77                                c = cmdline[src];
  78                                if (!c) {
  79                                        free(*argv);
  80                                        *argv = NULL;
  81                                        return error("cmdline ends with \\");
  82                                }
  83                        }
  84                        cmdline[dst++] = c;
  85                        src++;
  86                }
  87        }
  88
  89        cmdline[dst] = 0;
  90
  91        if (quoted) {
  92                free(*argv);
  93                *argv = NULL;
  94                return error("unclosed quote");
  95        }
  96
  97        return count;
  98}
  99
 100static int handle_alias(int *argcp, const char ***argv)
 101{
 102        int nongit = 0, ret = 0;
 103        const char *subdir;
 104
 105        subdir = setup_git_directory_gently(&nongit);
 106        if (!nongit) {
 107                int count;
 108                const char** new_argv;
 109
 110                alias_command = (*argv)[0];
 111                git_config(git_alias_config);
 112                if (alias_string) {
 113
 114                        count = split_cmdline(alias_string, &new_argv);
 115
 116                        if (count < 1)
 117                                die("empty alias for %s", alias_command);
 118
 119                        if (!strcmp(alias_command, new_argv[0]))
 120                                die("recursive alias: %s", alias_command);
 121
 122                        /* insert after command name */
 123                        if (*argcp > 1) {
 124                                new_argv = realloc(new_argv, sizeof(char*) *
 125                                                (count + *argcp - 1));
 126                                memcpy(new_argv + count, *argv, sizeof(char*) *
 127                                                (*argcp - 1));
 128                        }
 129
 130                        *argv = new_argv;
 131                        *argcp += count - 1;
 132
 133                        ret = 1;
 134                }
 135        }
 136
 137        if (subdir)
 138                chdir(subdir);
 139
 140        return ret;
 141}
 142
 143const char git_version_string[] = GIT_VERSION;
 144
 145static void handle_internal_command(int argc, const char **argv, char **envp)
 146{
 147        const char *cmd = argv[0];
 148        static struct cmd_struct {
 149                const char *cmd;
 150                int (*fn)(int, const char **, char **);
 151        } commands[] = {
 152                { "version", cmd_version },
 153                { "help", cmd_help },
 154                { "log", cmd_log },
 155                { "whatchanged", cmd_whatchanged },
 156                { "show", cmd_show },
 157                { "push", cmd_push },
 158                { "format-patch", cmd_format_patch },
 159                { "count-objects", cmd_count_objects },
 160                { "diff", cmd_diff },
 161                { "grep", cmd_grep },
 162                { "rm", cmd_rm },
 163                { "add", cmd_add },
 164                { "rev-list", cmd_rev_list },
 165                { "init-db", cmd_init_db },
 166                { "tar-tree", cmd_tar_tree },
 167                { "upload-tar", cmd_upload_tar },
 168                { "check-ref-format", cmd_check_ref_format },
 169                { "ls-files", cmd_ls_files },
 170                { "ls-tree", cmd_ls_tree },
 171                { "tar-tree", cmd_tar_tree },
 172                { "read-tree", cmd_read_tree },
 173                { "commit-tree", cmd_commit_tree },
 174                { "apply", cmd_apply },
 175                { "show-branch", cmd_show_branch },
 176                { "diff-files", cmd_diff_files },
 177                { "diff-index", cmd_diff_index },
 178                { "diff-stages", cmd_diff_stages },
 179                { "diff-tree", cmd_diff_tree },
 180                { "cat-file", cmd_cat_file },
 181                { "rev-parse", cmd_rev_parse }
 182        };
 183        int i;
 184
 185        /* Turn "git cmd --help" into "git help cmd" */
 186        if (argc > 1 && !strcmp(argv[1], "--help")) {
 187                argv[1] = argv[0];
 188                argv[0] = cmd = "help";
 189        }
 190
 191        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 192                struct cmd_struct *p = commands+i;
 193                if (strcmp(p->cmd, cmd))
 194                        continue;
 195                exit(p->fn(argc, argv, envp));
 196        }
 197}
 198
 199int main(int argc, const char **argv, char **envp)
 200{
 201        const char *cmd = argv[0];
 202        char *slash = strrchr(cmd, '/');
 203        char git_command[PATH_MAX + 1];
 204        const char *exec_path = NULL;
 205        int done_alias = 0;
 206
 207        /*
 208         * Take the basename of argv[0] as the command
 209         * name, and the dirname as the default exec_path
 210         * if it's an absolute path and we don't have
 211         * anything better.
 212         */
 213        if (slash) {
 214                *slash++ = 0;
 215                if (*cmd == '/')
 216                        exec_path = cmd;
 217                cmd = slash;
 218        }
 219
 220        /*
 221         * "git-xxxx" is the same as "git xxxx", but we obviously:
 222         *
 223         *  - cannot take flags in between the "git" and the "xxxx".
 224         *  - cannot execute it externally (since it would just do
 225         *    the same thing over again)
 226         *
 227         * So we just directly call the internal command handler, and
 228         * die if that one cannot handle it.
 229         */
 230        if (!strncmp(cmd, "git-", 4)) {
 231                cmd += 4;
 232                argv[0] = cmd;
 233                handle_internal_command(argc, argv, envp);
 234                die("cannot handle %s internally", cmd);
 235        }
 236
 237        /* Default command: "help" */
 238        cmd = "help";
 239
 240        /* Look for flags.. */
 241        while (argc > 1) {
 242                cmd = *++argv;
 243                argc--;
 244
 245                if (strncmp(cmd, "--", 2))
 246                        break;
 247
 248                cmd += 2;
 249
 250                /*
 251                 * For legacy reasons, the "version" and "help"
 252                 * commands can be written with "--" prepended
 253                 * to make them look like flags.
 254                 */
 255                if (!strcmp(cmd, "help"))
 256                        break;
 257                if (!strcmp(cmd, "version"))
 258                        break;
 259
 260                /*
 261                 * Check remaining flags (which by now must be
 262                 * "--exec-path", but maybe we will accept
 263                 * other arguments some day)
 264                 */
 265                if (!strncmp(cmd, "exec-path", 9)) {
 266                        cmd += 9;
 267                        if (*cmd == '=') {
 268                                git_set_exec_path(cmd + 1);
 269                                continue;
 270                        }
 271                        puts(git_exec_path());
 272                        exit(0);
 273                }
 274                cmd_usage(0, NULL, NULL);
 275        }
 276        argv[0] = cmd;
 277
 278        /*
 279         * We search for git commands in the following order:
 280         *  - git_exec_path()
 281         *  - the path of the "git" command if we could find it
 282         *    in $0
 283         *  - the regular PATH.
 284         */
 285        if (exec_path)
 286                prepend_to_path(exec_path, strlen(exec_path));
 287        exec_path = git_exec_path();
 288        prepend_to_path(exec_path, strlen(exec_path));
 289
 290        while (1) {
 291                /* See if it's an internal command */
 292                handle_internal_command(argc, argv, envp);
 293
 294                /* .. then try the external ones */
 295                execv_git_cmd(argv);
 296
 297                /* It could be an alias -- this works around the insanity
 298                 * of overriding "git log" with "git show" by having
 299                 * alias.log = show
 300                 */
 301                if (done_alias || !handle_alias(&argc, &argv))
 302                        break;
 303                done_alias = 1;
 304        }
 305
 306        if (errno == ENOENT)
 307                cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
 308
 309        fprintf(stderr, "Failed to run command '%s': %s\n",
 310                git_command, strerror(errno));
 311
 312        return 1;
 313}