run-command.c

   1 #include "cache.h"
   2 #include "run-command.h"
   3 #include "exec_cmd.h"
   4
   5 int start_command(struct child_process *cmd)
   6 {
   7         int need_in = !cmd->no_stdin && cmd->in < 0;
   8         int fdin[2];
   9
  10         if (need_in) {
  11                 if (pipe(fdin) < 0)
  12                         return -ERR_RUN_COMMAND_PIPE;
  13                 cmd->in = fdin[1];
  14                 cmd->close_in = 1;
  15         }
  16
  17         cmd->pid = fork();
  18         if (cmd->pid < 0) {
  19                 if (need_in) {
  20                         close(fdin[0]);
  21                         close(fdin[1]);
  22                 }
  23                 return -ERR_RUN_COMMAND_FORK;
  24         }
  25
  26         if (!cmd->pid) {
  27                 if (cmd->no_stdin) {
  28                         int fd = open("/dev/null", O_RDWR);
  29                         dup2(fd, 0);
  30                         close(fd);
  31                 } else if (need_in) {
  32                         dup2(fdin[0], 0);
  33                         close(fdin[0]);
  34                         close(fdin[1]);
  35                 } else if (cmd->in) {
  36                         dup2(cmd->in, 0);
  37                         close(cmd->in);
  38                 }
  39
  40                 if (cmd->stdout_to_stderr)
  41                         dup2(2, 1);
  42                 if (cmd->git_cmd) {
  43                         execv_git_cmd(cmd->argv);
  44                 } else {
  45                         execvp(cmd->argv[0], (char *const*) cmd->argv);
  46                 }
  47                 die("exec %s failed.", cmd->argv[0]);
  48         }
  49
  50         if (need_in)
  51                 close(fdin[0]);
  52         else if (cmd->in)
  53                 close(cmd->in);
  54
  55         return 0;
  56 }
  57
  58 int finish_command(struct child_process *cmd)
  59 {
  60         if (cmd->close_in)
  61                 close(cmd->in);
  62
  63         for (;;) {
  64                 int status, code;
  65                 pid_t waiting = waitpid(cmd->pid, &status, 0);
  66
  67                 if (waiting < 0) {
  68                         if (errno == EINTR)
  69                                 continue;
  70                         error("waitpid failed (%s)", strerror(errno));
  71                         return -ERR_RUN_COMMAND_WAITPID;
  72                 }
  73                 if (waiting != cmd->pid)
  74                         return -ERR_RUN_COMMAND_WAITPID_WRONG_PID;
  75                 if (WIFSIGNALED(status))
  76                         return -ERR_RUN_COMMAND_WAITPID_SIGNAL;
  77
  78                 if (!WIFEXITED(status))
  79                         return -ERR_RUN_COMMAND_WAITPID_NOEXIT;
  80                 code = WEXITSTATUS(status);
  81                 if (code)
  82                         return -code;
  83                 return 0;
  84         }
  85 }
  86
  87 int run_command(struct child_process *cmd)
  88 {
  89         int code = start_command(cmd);
  90         if (code)
  91                 return code;
  92         return finish_command(cmd);
  93 }
  94
  95 int run_command_v_opt(const char **argv, int opt)
  96 {
  97         struct child_process cmd;
  98         memset(&cmd, 0, sizeof(cmd));
  99         cmd.argv = argv;
 100         cmd.no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
 101         cmd.git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
 102         cmd.stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
 103         return run_command(&cmd);
 104 }