Function pp_buffer_io

run-command.c:1729–1796

}

static void pp_buffer_io(struct parallel_processes *pp,
			 const struct run_process_parallel_opts *opts,
			 int timeout)
{
	/* for each potential child slot, prepare two pollfd entries */
	for (size_t i = 0; i < opts->processes; i++) {
		if (child_is_sending_output(&pp->children[i])) {
			pp->pfd[2*i].fd = pp->children[i].process.err;
			pp->pfd[2*i].events = POLLIN | POLLHUP;
		} else {
			pp->pfd[2*i].fd = -1;
		}

		if (child_is_receiving_input(&pp->children[i])) {
			pp->pfd[2*i+1].fd = pp->children[i].process.in;
			pp->pfd[2*i+1].events = POLLOUT;
		} else {
			pp->pfd[2*i+1].fd = -1;
		}
	}

	while (poll(pp->pfd, opts->processes * 2, timeout) < 0) {
		if (errno == EINTR)
			continue;
		pp_cleanup(pp, opts);
		die_errno("poll");
	}

	for (size_t i = 0; i < opts->processes; i++) {
		/* Handle input feeding (stdin) */
		if (pp->pfd[2*i+1].revents & (POLLOUT | POLLHUP | POLLERR)) {
			if (opts->feed_pipe) {
				int ret = opts->feed_pipe(pp->children[i].process.in,
							  opts->data,
							  pp->children[i].data);
				if (ret < 0)
					die_errno("feed_pipe");
				if (ret) {
					/* done feeding */
					close(pp->children[i].process.in);
					pp->children[i].process.in = 0;
				}
			} else {
				/*
				 * No feed_pipe means there is nothing to do, so
				 * close the fd. Child input can be fed by other
				 * methods, such as opts->path_to_stdin which
				 * slurps a file via dup2, so clean up here.
				 */
				close(pp->children[i].process.in);
				pp->children[i].process.in = 0;
			}
		}

		/* Handle output reading (stderr) */
		if (child_is_working(&pp->children[i]) &&
		    pp->pfd[2*i].revents & (POLLIN | POLLHUP)) {
			int n = strbuf_read_once(&pp->children[i].err,