Add run_command_v_opt_cd: chdir into a directory before exec

[thirdparty/git.git] / run-command.c

diff --git a/run-command.c b/run-command.c
index ca67ee9333e1f4125678fe607f44d75becc3cf7e..043b5701a1bb888b5b4fce9299b9dc28c176d09e 100644 (file)
--- a/run-command.c
+++ b/run-command.c
@@ -1,39 +1,120 @@
 #include "cache.h"
 #include "run-command.h"
-#include <sys/wait.h>
 #include "exec_cmd.h"
 
-int run_command_v_opt(int argc, const char **argv, int flags)
+static inline void close_pair(int fd[2])
 {
-       pid_t pid = fork();
+       close(fd[0]);
+       close(fd[1]);
+}
+
+static inline void dup_devnull(int to)
+{
+       int fd = open("/dev/null", O_RDWR);
+       dup2(fd, to);
+       close(fd);
+}
+
+int start_command(struct child_process *cmd)
+{
+       int need_in, need_out;
+       int fdin[2], fdout[2];
+
+       need_in = !cmd->no_stdin && cmd->in < 0;
+       if (need_in) {
+               if (pipe(fdin) < 0)
+                       return -ERR_RUN_COMMAND_PIPE;
+               cmd->in = fdin[1];
+               cmd->close_in = 1;
+       }
 
-       if (pid < 0)
+       need_out = !cmd->no_stdout
+               && !cmd->stdout_to_stderr
+               && cmd->out < 0;
+       if (need_out) {
+               if (pipe(fdout) < 0) {
+                       if (need_in)
+                               close_pair(fdin);
+                       return -ERR_RUN_COMMAND_PIPE;
+               }
+               cmd->out = fdout[0];
+               cmd->close_out = 1;
+       }
+
+       cmd->pid = fork();
+       if (cmd->pid < 0) {
+               if (need_in)
+                       close_pair(fdin);
+               if (need_out)
+                       close_pair(fdout);
                return -ERR_RUN_COMMAND_FORK;
-       if (!pid) {
-               if (flags & RUN_COMMAND_NO_STDIO) {
-                       int fd = open("/dev/null", O_RDWR);
-                       dup2(fd, 0);
-                       dup2(fd, 1);
-                       close(fd);
+       }
+
+       if (!cmd->pid) {
+               if (cmd->no_stdin)
+                       dup_devnull(0);
+               else if (need_in) {
+                       dup2(fdin[0], 0);
+                       close_pair(fdin);
+               } else if (cmd->in) {
+                       dup2(cmd->in, 0);
+                       close(cmd->in);
+               }
+
+               if (cmd->no_stdout)
+                       dup_devnull(1);
+               else if (cmd->stdout_to_stderr)
+                       dup2(2, 1);
+               else if (need_out) {
+                       dup2(fdout[1], 1);
+                       close_pair(fdout);
+               } else if (cmd->out > 1) {
+                       dup2(cmd->out, 1);
+                       close(cmd->out);
                }
-               if (flags & RUN_GIT_CMD) {
-                       execv_git_cmd(argv);
+
+               if (cmd->dir && chdir(cmd->dir))
+                       die("exec %s: cd to %s failed (%s)", cmd->argv[0],
+                           cmd->dir, strerror(errno));
+               if (cmd->git_cmd) {
+                       execv_git_cmd(cmd->argv);
                } else {
-                       execvp(argv[0], (char *const*) argv);
+                       execvp(cmd->argv[0], (char *const*) cmd->argv);
                }
-               die("exec %s failed.", argv[0]);
+               die("exec %s failed.", cmd->argv[0]);
        }
+
+       if (need_in)
+               close(fdin[0]);
+       else if (cmd->in)
+               close(cmd->in);
+
+       if (need_out)
+               close(fdout[1]);
+       else if (cmd->out > 1)
+               close(cmd->out);
+
+       return 0;
+}
+
+int finish_command(struct child_process *cmd)
+{
+       if (cmd->close_in)
+               close(cmd->in);
+       if (cmd->close_out)
+               close(cmd->out);
+
        for (;;) {
                int status, code;
-               int retval = waitpid(pid, &status, 0);
+               pid_t waiting = waitpid(cmd->pid, &status, 0);
 
-               if (retval < 0) {
+               if (waiting < 0) {
                        if (errno == EINTR)
                                continue;
-                       error("waitpid failed (%s)", strerror(retval));
+                       error("waitpid failed (%s)", strerror(errno));
                        return -ERR_RUN_COMMAND_WAITPID;
                }
-               if (retval != pid)
+               if (waiting != cmd->pid)
                        return -ERR_RUN_COMMAND_WAITPID_WRONG_PID;
                if (WIFSIGNALED(status))
                        return -ERR_RUN_COMMAND_WAITPID_SIGNAL;
@@ -47,28 +128,35 @@ int run_command_v_opt(int argc, const char **argv, int flags)
        }
 }
 
-int run_command_v(int argc, const char **argv)
+int run_command(struct child_process *cmd)
 {
-       return run_command_v_opt(argc, argv, 0);
+       int code = start_command(cmd);
+       if (code)
+               return code;
+       return finish_command(cmd);
 }
 
-int run_command(const char *cmd, ...)
+static void prepare_run_command_v_opt(struct child_process *cmd,
+                                     const char **argv, int opt)
 {
-       int argc;
-       const char *argv[MAX_RUN_COMMAND_ARGS];
-       const char *arg;
-       va_list param;
-
-       va_start(param, cmd);
-       argv[0] = (char*) cmd;
-       argc = 1;
-       while (argc < MAX_RUN_COMMAND_ARGS) {
-               arg = argv[argc++] = va_arg(param, char *);
-               if (!arg)
-                       break;
-       }
-       va_end(param);
-       if (MAX_RUN_COMMAND_ARGS <= argc)
-               return error("too many args to run %s", cmd);
-       return run_command_v_opt(argc, argv, 0);
+       memset(cmd, 0, sizeof(*cmd));
+       cmd->argv = argv;
+       cmd->no_stdin = opt & RUN_COMMAND_NO_STDIN ? 1 : 0;
+       cmd->git_cmd = opt & RUN_GIT_CMD ? 1 : 0;
+       cmd->stdout_to_stderr = opt & RUN_COMMAND_STDOUT_TO_STDERR ? 1 : 0;
+}
+
+int run_command_v_opt(const char **argv, int opt)
+{
+       struct child_process cmd;
+       prepare_run_command_v_opt(&cmd, argv, opt);
+       return run_command(&cmd);
+}
+
+int run_command_v_opt_cd(const char **argv, int opt, const char *dir)
+{
+       struct child_process cmd;
+       prepare_run_command_v_opt(&cmd, argv, opt);
+       cmd.dir = dir;
+       return run_command(&cmd);
 }