Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "run-command.h"
   3#include "exec_cmd.h"
   4
   5static inline void close_pair(int fd[2])
   6{
   7        close(fd[0]);
   8        close(fd[1]);
   9}
  10
  11#ifndef WIN32
  12static inline void dup_devnull(int to)
  13{
  14        int fd = open("/dev/null", O_RDWR);
  15        dup2(fd, to);
  16        close(fd);
  17}
  18#endif
  19
  20int start_command(struct child_process *cmd)
  21{
  22        int need_in, need_out, need_err;
  23        int fdin[2], fdout[2], fderr[2];
  24        int failed_errno = failed_errno;
  25
  26        /*
  27         * In case of errors we must keep the promise to close FDs
  28         * that have been passed in via ->in and ->out.
  29         */
  30
  31        need_in = !cmd->no_stdin && cmd->in < 0;
  32        if (need_in) {
  33                if (pipe(fdin) < 0) {
  34                        failed_errno = errno;
  35                        if (cmd->out > 0)
  36                                close(cmd->out);
  37                        goto fail_pipe;
  38                }
  39                cmd->in = fdin[1];
  40        }
  41
  42        need_out = !cmd->no_stdout
  43                && !cmd->stdout_to_stderr
  44                && cmd->out < 0;
  45        if (need_out) {
  46                if (pipe(fdout) < 0) {
  47                        failed_errno = errno;
  48                        if (need_in)
  49                                close_pair(fdin);
  50                        else if (cmd->in)
  51                                close(cmd->in);
  52                        goto fail_pipe;
  53                }
  54                cmd->out = fdout[0];
  55        }
  56
  57        need_err = !cmd->no_stderr && cmd->err < 0;
  58        if (need_err) {
  59                if (pipe(fderr) < 0) {
  60                        failed_errno = errno;
  61                        if (need_in)
  62                                close_pair(fdin);
  63                        else if (cmd->in)
  64                                close(cmd->in);
  65                        if (need_out)
  66                                close_pair(fdout);
  67                        else if (cmd->out)
  68                                close(cmd->out);
  69fail_pipe:
  70                        error("cannot create pipe for %s: %s",
  71                                cmd->argv[0], strerror(failed_errno));
  72                        errno = failed_errno;
  73                        return -1;
  74                }
  75                cmd->err = fderr[0];
  76        }
  77
  78        trace_argv_printf(cmd->argv, "trace: run_command:");
  79
  80#ifndef WIN32
  81        fflush(NULL);
  82        cmd->pid = fork();
  83        if (!cmd->pid) {
  84                if (cmd->no_stdin)
  85                        dup_devnull(0);
  86                else if (need_in) {
  87                        dup2(fdin[0], 0);
  88                        close_pair(fdin);
  89                } else if (cmd->in) {
  90                        dup2(cmd->in, 0);
  91                        close(cmd->in);
  92                }
  93
  94                if (cmd->no_stderr)
  95                        dup_devnull(2);
  96                else if (need_err) {
  97                        dup2(fderr[1], 2);
  98                        close_pair(fderr);
  99                }
 100
 101                if (cmd->no_stdout)
 102                        dup_devnull(1);
 103                else if (cmd->stdout_to_stderr)
 104                        dup2(2, 1);
 105                else if (need_out) {
 106                        dup2(fdout[1], 1);
 107                        close_pair(fdout);
 108                } else if (cmd->out > 1) {
 109                        dup2(cmd->out, 1);
 110                        close(cmd->out);
 111                }
 112
 113                if (cmd->dir && chdir(cmd->dir))
 114                        die_errno("exec '%s': cd to '%s' failed", cmd->argv[0],
 115                            cmd->dir);
 116                if (cmd->env) {
 117                        for (; *cmd->env; cmd->env++) {
 118                                if (strchr(*cmd->env, '='))
 119                                        putenv((char *)*cmd->env);
 120                                else
 121                                        unsetenv(*cmd->env);
 122                        }
 123                }
 124                if (cmd->preexec_cb)
 125                        cmd->preexec_cb();
 126                if (cmd->git_cmd) {
 127                        execv_git_cmd(cmd->argv);
 128                } else {
 129                        execvp(cmd->argv[0], (char *const*) cmd->argv);
 130                }
 131                trace_printf("trace: exec '%s' failed: %s\n", cmd->argv[0],
 132                                strerror(errno));
 133                exit(127);
 134        }
 135        if (cmd->pid < 0)
 136                error("cannot fork() for %s: %s", cmd->argv[0],
 137                        strerror(failed_errno = errno));
 138#else
 139{
 140        int fhin = 0, fhout = 1, fherr = 2;
 141        const char **sargv = cmd->argv;
 142        char **env = environ;
 143
 144        if (cmd->no_stdin)
 145                fhin = open("/dev/null", O_RDWR);
 146        else if (need_in)
 147                fhin = dup(fdin[0]);
 148        else if (cmd->in)
 149                fhin = dup(cmd->in);
 150
 151        if (cmd->no_stderr)
 152                fherr = open("/dev/null", O_RDWR);
 153        else if (need_err)
 154                fherr = dup(fderr[1]);
 155
 156        if (cmd->no_stdout)
 157                fhout = open("/dev/null", O_RDWR);
 158        else if (cmd->stdout_to_stderr)
 159                fhout = dup(fherr);
 160        else if (need_out)
 161                fhout = dup(fdout[1]);
 162        else if (cmd->out > 1)
 163                fhout = dup(cmd->out);
 164
 165        if (cmd->dir)
 166                die("chdir in start_command() not implemented");
 167        if (cmd->env)
 168                env = make_augmented_environ(cmd->env);
 169
 170        if (cmd->git_cmd) {
 171                cmd->argv = prepare_git_cmd(cmd->argv);
 172        }
 173
 174        cmd->pid = mingw_spawnvpe(cmd->argv[0], cmd->argv, env,
 175                                  fhin, fhout, fherr);
 176        failed_errno = errno;
 177        if (cmd->pid < 0 && (!cmd->silent_exec_failure || errno != ENOENT))
 178                error("cannot spawn %s: %s", cmd->argv[0], strerror(errno));
 179
 180        if (cmd->env)
 181                free_environ(env);
 182        if (cmd->git_cmd)
 183                free(cmd->argv);
 184
 185        cmd->argv = sargv;
 186        if (fhin != 0)
 187                close(fhin);
 188        if (fhout != 1)
 189                close(fhout);
 190        if (fherr != 2)
 191                close(fherr);
 192}
 193#endif
 194
 195        if (cmd->pid < 0) {
 196                if (need_in)
 197                        close_pair(fdin);
 198                else if (cmd->in)
 199                        close(cmd->in);
 200                if (need_out)
 201                        close_pair(fdout);
 202                else if (cmd->out)
 203                        close(cmd->out);
 204                if (need_err)
 205                        close_pair(fderr);
 206                errno = failed_errno;
 207                return -1;
 208        }
 209
 210        if (need_in)
 211                close(fdin[0]);
 212        else if (cmd->in)
 213                close(cmd->in);
 214
 215        if (need_out)
 216                close(fdout[1]);
 217        else if (cmd->out)
 218                close(cmd->out);
 219
 220        if (need_err)
 221                close(fderr[1]);
 222
 223        return 0;
 224}
 225
 226static int wait_or_whine(pid_t pid, const char *argv0, int silent_exec_failure)
 227{
 228        int status, code = -1;
 229        pid_t waiting;
 230        int failed_errno = 0;
 231
 232        while ((waiting = waitpid(pid, &status, 0)) < 0 && errno == EINTR)
 233                ;       /* nothing */
 234
 235        if (waiting < 0) {
 236                failed_errno = errno;
 237                error("waitpid for %s failed: %s", argv0, strerror(errno));
 238        } else if (waiting != pid) {
 239                error("waitpid is confused (%s)", argv0);
 240        } else if (WIFSIGNALED(status)) {
 241                code = WTERMSIG(status);
 242                error("%s died of signal %d", argv0, code);
 243                /*
 244                 * This return value is chosen so that code & 0xff
 245                 * mimics the exit code that a POSIX shell would report for
 246                 * a program that died from this signal.
 247                 */
 248                code -= 128;
 249        } else if (WIFEXITED(status)) {
 250                code = WEXITSTATUS(status);
 251                /*
 252                 * Convert special exit code when execvp failed.
 253                 */
 254                if (code == 127) {
 255                        code = -1;
 256                        failed_errno = ENOENT;
 257                        if (!silent_exec_failure)
 258                                error("cannot run %s: %s", argv0,
 259                                        strerror(ENOENT));
 260                }
 261        } else {
 262                error("waitpid is confused (%s)", argv0);
 263        }
 264        errno = failed_errno;
 265        return code;
 266}
 267
 268int finish_command(struct child_process *cmd)
 269{
 270        return wait_or_whine(cmd->pid, cmd->argv[0], cmd->silent_exec_failure);
 271}
 272
 273int run_command(struct child_process *cmd)
 274{
 275        int code = start_command(cmd);
 276        if (code)
 277                return code;
 278        return finish_command(cmd);
 279}
 280
 281static void prepare_run_command_v_opt(struct child_process *cmd,
 282                                      const char **argv,
 283                                      int opt)
 284{
 285        memset(cmd, 0, sizeof(*cmd));
 286        cmd->argv = argv;
 287        cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
 288        cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
 289        cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
 290        cmd->silent_exec_failure = opt & RUN_SILENT_EXEC_FAILURE ? 1 : 0;
 291}
 292
 293int run_command_v_opt(const char **argv, int opt)
 294{
 295        struct child_process cmd;
 296        prepare_run_command_v_opt(&cmd, argv, opt);
 297        return run_command(&cmd);
 298}
 299
 300int run_command_v_opt_cd_env(const char **argv, int opt, const char *dir, const char *const *env)
 301{
 302        struct child_process cmd;
 303        prepare_run_command_v_opt(&cmd, argv, opt);
 304        cmd.dir = dir;
 305        cmd.env = env;
 306        return run_command(&cmd);
 307}
 308
 309#ifdef WIN32
 310static unsigned __stdcall run_thread(void *data)
 311{
 312        struct async *async = data;
 313        return async->proc(async->fd_for_proc, async->data);
 314}
 315#endif
 316
 317int start_async(struct async *async)
 318{
 319        int pipe_out[2];
 320
 321        if (pipe(pipe_out) < 0)
 322                return error("cannot create pipe: %s", strerror(errno));
 323        async->out = pipe_out[0];
 324
 325#ifndef WIN32
 326        /* Flush stdio before fork() to avoid cloning buffers */
 327        fflush(NULL);
 328
 329        async->pid = fork();
 330        if (async->pid < 0) {
 331                error("fork (async) failed: %s", strerror(errno));
 332                close_pair(pipe_out);
 333                return -1;
 334        }
 335        if (!async->pid) {
 336                close(pipe_out[0]);
 337                exit(!!async->proc(pipe_out[1], async->data));
 338        }
 339        close(pipe_out[1]);
 340#else
 341        async->fd_for_proc = pipe_out[1];
 342        async->tid = (HANDLE) _beginthreadex(NULL, 0, run_thread, async, 0, NULL);
 343        if (!async->tid) {
 344                error("cannot create thread: %s", strerror(errno));
 345                close_pair(pipe_out);
 346                return -1;
 347        }
 348#endif
 349        return 0;
 350}
 351
 352int finish_async(struct async *async)
 353{
 354#ifndef WIN32
 355        int ret = wait_or_whine(async->pid, "child process", 0);
 356#else
 357        DWORD ret = 0;
 358        if (WaitForSingleObject(async->tid, INFINITE) != WAIT_OBJECT_0)
 359                ret = error("waiting for thread failed: %lu", GetLastError());
 360        else if (!GetExitCodeThread(async->tid, &ret))
 361                ret = error("cannot get thread exit code: %lu", GetLastError());
 362        CloseHandle(async->tid);
 363#endif
 364        return ret;
 365}
 366
 367int run_hook(const char *index_file, const char *name, ...)
 368{
 369        struct child_process hook;
 370        const char **argv = NULL, *env[2];
 371        char index[PATH_MAX];
 372        va_list args;
 373        int ret;
 374        size_t i = 0, alloc = 0;
 375
 376        if (access(git_path("hooks/%s", name), X_OK) < 0)
 377                return 0;
 378
 379        va_start(args, name);
 380        ALLOC_GROW(argv, i + 1, alloc);
 381        argv[i++] = git_path("hooks/%s", name);
 382        while (argv[i-1]) {
 383                ALLOC_GROW(argv, i + 1, alloc);
 384                argv[i++] = va_arg(args, const char *);
 385        }
 386        va_end(args);
 387
 388        memset(&hook, 0, sizeof(hook));
 389        hook.argv = argv;
 390        hook.no_stdin = 1;
 391        hook.stdout_to_stderr = 1;
 392        if (index_file) {
 393                snprintf(index, sizeof(index), "GIT_INDEX_FILE=%s", index_file);
 394                env[0] = index;
 395                env[1] = NULL;
 396                hook.env = env;
 397        }
 398
 399        ret = run_command(&hook);
 400        free(argv);
 401        return ret;
 402}