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        const char *old_path = getenv("PATH");
  20        char *path;
  21        int path_len = len;
  22
  23        if (!old_path)
  24                old_path = "/usr/local/bin:/usr/bin:/bin";
  25
  26        path_len = len + strlen(old_path) + 1;
  27
  28        path = malloc(path_len + 1);
  29
  30        memcpy(path, dir, len);
  31        path[len] = ':';
  32        memcpy(path + len + 1, old_path, path_len - len);
  33
  34        setenv("PATH", path, 1);
  35}
  36
  37static const char *alias_command;
  38static char *alias_string = NULL;
  39
  40static int git_alias_config(const char *var, const char *value)
  41{
  42        if (!strncmp(var, "alias.", 6) && !strcmp(var + 6, alias_command)) {
  43                alias_string = strdup(value);
  44        }
  45        return 0;
  46}
  47
  48static int split_cmdline(char *cmdline, const char ***argv)
  49{
  50        int src, dst, count = 0, size = 16;
  51        char quoted = 0;
  52
  53        *argv = malloc(sizeof(char*) * size);
  54
  55        /* split alias_string */
  56        (*argv)[count++] = cmdline;
  57        for (src = dst = 0; cmdline[src];) {
  58                char c = cmdline[src];
  59                if (!quoted && isspace(c)) {
  60                        cmdline[dst++] = 0;
  61                        while (cmdline[++src]
  62                                        && isspace(cmdline[src]))
  63                                ; /* skip */
  64                        if (count >= size) {
  65                                size += 16;
  66                                *argv = realloc(*argv, sizeof(char*) * size);
  67                        }
  68                        (*argv)[count++] = cmdline + dst;
  69                } else if(!quoted && (c == '\'' || c == '"')) {
  70                        quoted = c;
  71                        src++;
  72                } else if (c == quoted) {
  73                        quoted = 0;
  74                        src++;
  75                } else {
  76                        if (c == '\\' && quoted != '\'') {
  77                                src++;
  78                                c = cmdline[src];
  79                                if (!c) {
  80                                        free(*argv);
  81                                        *argv = NULL;
  82                                        return error("cmdline ends with \\");
  83                                }
  84                        }
  85                        cmdline[dst++] = c;
  86                        src++;
  87                }
  88        }
  89
  90        cmdline[dst] = 0;
  91
  92        if (quoted) {
  93                free(*argv);
  94                *argv = NULL;
  95                return error("unclosed quote");
  96        }
  97
  98        return count;
  99}
 100
 101static int handle_alias(int *argcp, const char ***argv)
 102{
 103        int nongit = 0, ret = 0;
 104        const char *subdir;
 105
 106        subdir = setup_git_directory_gently(&nongit);
 107        if (!nongit) {
 108                int count;
 109                const char** new_argv;
 110
 111                alias_command = (*argv)[0];
 112                git_config(git_alias_config);
 113                if (alias_string) {
 114
 115                        count = split_cmdline(alias_string, &new_argv);
 116
 117                        if (count < 1)
 118                                die("empty alias for %s", alias_command);
 119
 120                        if (!strcmp(alias_command, new_argv[0]))
 121                                die("recursive alias: %s", alias_command);
 122
 123                        /* insert after command name */
 124                        if (*argcp > 1) {
 125                                new_argv = realloc(new_argv, sizeof(char*) *
 126                                                   (count + *argcp));
 127                                memcpy(new_argv + count, *argv + 1,
 128                                       sizeof(char*) * *argcp);
 129                        }
 130
 131                        *argv = new_argv;
 132                        *argcp += count - 1;
 133
 134                        ret = 1;
 135                }
 136        }
 137
 138        if (subdir)
 139                chdir(subdir);
 140
 141        return ret;
 142}
 143
 144const char git_version_string[] = GIT_VERSION;
 145
 146static void handle_internal_command(int argc, const char **argv, char **envp)
 147{
 148        const char *cmd = argv[0];
 149        static struct cmd_struct {
 150                const char *cmd;
 151                int (*fn)(int, const char **, char **);
 152        } commands[] = {
 153                { "version", cmd_version },
 154                { "help", cmd_help },
 155                { "log", cmd_log },
 156                { "whatchanged", cmd_whatchanged },
 157                { "show", cmd_show },
 158                { "push", cmd_push },
 159                { "format-patch", cmd_format_patch },
 160                { "count-objects", cmd_count_objects },
 161                { "diff", cmd_diff },
 162                { "grep", cmd_grep },
 163                { "rm", cmd_rm },
 164                { "add", cmd_add },
 165                { "rev-list", cmd_rev_list },
 166                { "init-db", cmd_init_db },
 167                { "get-tar-commit-id", cmd_get_tar_commit_id },
 168                { "upload-tar", cmd_upload_tar },
 169                { "check-ref-format", cmd_check_ref_format },
 170                { "ls-files", cmd_ls_files },
 171                { "ls-tree", cmd_ls_tree },
 172                { "tar-tree", cmd_tar_tree },
 173                { "read-tree", cmd_read_tree },
 174                { "commit-tree", cmd_commit_tree },
 175                { "apply", cmd_apply },
 176                { "show-branch", cmd_show_branch },
 177                { "diff-files", cmd_diff_files },
 178                { "diff-index", cmd_diff_index },
 179                { "diff-stages", cmd_diff_stages },
 180                { "diff-tree", cmd_diff_tree },
 181                { "cat-file", cmd_cat_file },
 182                { "rev-parse", cmd_rev_parse },
 183                { "write-tree", cmd_write_tree },
 184                { "mailsplit", cmd_mailsplit },
 185                { "mailinfo", cmd_mailinfo },
 186                { "stripspace", cmd_stripspace },
 187                { "update-index", cmd_update_index },
 188                { "update-ref", cmd_update_ref }
 189        };
 190        int i;
 191
 192        /* Turn "git cmd --help" into "git help cmd" */
 193        if (argc > 1 && !strcmp(argv[1], "--help")) {
 194                argv[1] = argv[0];
 195                argv[0] = cmd = "help";
 196        }
 197
 198        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 199                struct cmd_struct *p = commands+i;
 200                if (strcmp(p->cmd, cmd))
 201                        continue;
 202                exit(p->fn(argc, argv, envp));
 203        }
 204}
 205
 206int main(int argc, const char **argv, char **envp)
 207{
 208        const char *cmd = argv[0];
 209        char *slash = strrchr(cmd, '/');
 210        const char *exec_path = NULL;
 211        int done_alias = 0;
 212
 213        /*
 214         * Take the basename of argv[0] as the command
 215         * name, and the dirname as the default exec_path
 216         * if it's an absolute path and we don't have
 217         * anything better.
 218         */
 219        if (slash) {
 220                *slash++ = 0;
 221                if (*cmd == '/')
 222                        exec_path = cmd;
 223                cmd = slash;
 224        }
 225
 226        /*
 227         * "git-xxxx" is the same as "git xxxx", but we obviously:
 228         *
 229         *  - cannot take flags in between the "git" and the "xxxx".
 230         *  - cannot execute it externally (since it would just do
 231         *    the same thing over again)
 232         *
 233         * So we just directly call the internal command handler, and
 234         * die if that one cannot handle it.
 235         */
 236        if (!strncmp(cmd, "git-", 4)) {
 237                cmd += 4;
 238                argv[0] = cmd;
 239                handle_internal_command(argc, argv, envp);
 240                die("cannot handle %s internally", cmd);
 241        }
 242
 243        /* Default command: "help" */
 244        cmd = "help";
 245
 246        /* Look for flags.. */
 247        while (argc > 1) {
 248                cmd = *++argv;
 249                argc--;
 250
 251                if (strncmp(cmd, "--", 2))
 252                        break;
 253
 254                cmd += 2;
 255
 256                /*
 257                 * For legacy reasons, the "version" and "help"
 258                 * commands can be written with "--" prepended
 259                 * to make them look like flags.
 260                 */
 261                if (!strcmp(cmd, "help"))
 262                        break;
 263                if (!strcmp(cmd, "version"))
 264                        break;
 265
 266                /*
 267                 * Check remaining flags (which by now must be
 268                 * "--exec-path", but maybe we will accept
 269                 * other arguments some day)
 270                 */
 271                if (!strncmp(cmd, "exec-path", 9)) {
 272                        cmd += 9;
 273                        if (*cmd == '=') {
 274                                git_set_exec_path(cmd + 1);
 275                                continue;
 276                        }
 277                        puts(git_exec_path());
 278                        exit(0);
 279                }
 280                cmd_usage(0, NULL, NULL);
 281        }
 282        argv[0] = cmd;
 283
 284        /*
 285         * We search for git commands in the following order:
 286         *  - git_exec_path()
 287         *  - the path of the "git" command if we could find it
 288         *    in $0
 289         *  - the regular PATH.
 290         */
 291        if (exec_path)
 292                prepend_to_path(exec_path, strlen(exec_path));
 293        exec_path = git_exec_path();
 294        prepend_to_path(exec_path, strlen(exec_path));
 295
 296        while (1) {
 297                /* See if it's an internal command */
 298                handle_internal_command(argc, argv, envp);
 299
 300                /* .. then try the external ones */
 301                execv_git_cmd(argv);
 302
 303                /* It could be an alias -- this works around the insanity
 304                 * of overriding "git log" with "git show" by having
 305                 * alias.log = show
 306                 */
 307                if (done_alias || !handle_alias(&argc, &argv))
 308                        break;
 309                done_alias = 1;
 310        }
 311
 312        if (errno == ENOENT)
 313                cmd_usage(0, exec_path, "'%s' is not a git-command", cmd);
 314
 315        fprintf(stderr, "Failed to run command '%s': %s\n",
 316                cmd, strerror(errno));
 317
 318        return 1;
 319}