Shawn O. PearceSome run-command callers may wish to just discard any data that is sent to stdout from the child. This is a lot like our existing no_stdin support, we just open /dev/null and duplicate the descriptor into position.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org> --- run-command.c | 26 ++++++++++++++++++-------- run-command.h | 1 + 2 files changed, 19 insertions(+), 8 deletions(-)
Show changes to 2 files +19 −8
run-command.c, run-command.h
diff --git a/run-command.c b/run-command.c index d20a6ef..eff523e 100644 --- a/run-command.c +++ b/run-command.c @@ -8,12 +8,19 @@ static inline void close_pair(int fd[2]) 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 = !cmd->no_stdin && cmd->in < 0; - int need_out = !cmd->stdout_to_stderr && cmd->out < 0; + 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; @@ -21,6 +28,9 @@ int start_command(struct child_process *cmd) cmd->close_in = 1; } + need_out = !cmd->no_stdout + && !cmd->stdout_to_stderr + && cmd->out < 0; if (need_out) { if (pipe(fdout) < 0) { if (need_in) @@ -41,11 +51,9 @@ int start_command(struct child_process *cmd) } if (!cmd->pid) { - if (cmd->no_stdin) { - int fd = open("/dev/null", O_RDWR); - dup2(fd, 0); - close(fd); - } else if (need_in) { + if (cmd->no_stdin) + dup_devnull(0); + else if (need_in) { dup2(fdin[0], 0); close_pair(fdin); } else if (cmd->in) { @@ -53,7 +61,9 @@ int start_command(struct child_process *cmd) close(cmd->in); } - if (cmd->stdout_to_stderr) + if (cmd->no_stdout) + dup_devnull(1); + else if (cmd->stdout_to_stderr) dup2(2, 1); else if (need_out) { dup2(fdout[1], 1); diff --git a/run-command.h b/run-command.h index 1c9126b..3680ef9 100644 --- a/run-command.h +++ b/run-command.h @@ -19,6 +19,7 @@ struct child_process { unsigned close_in:1; unsigned close_out:1; unsigned no_stdin:1; + unsigned no_stdout:1; unsigned git_cmd:1; /* if this is to be git sub-command */ unsigned stdout_to_stderr:1; };
-- 1.5.0.3.985.gcf0b4