#define _POSIX_C_SOURCE 200112L

#include <Xmd/Exec.h>
#include <Xmd/Buffer.h>

#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

FILE *XmdVaPipedExecPath (ConstString file, pid_t *child, String mode, ...) {
	XmdBuffer *buffer = XmdBufferNew(String);
	va_list argList;
	va_start(argList, mode);
	
	while (1) {
		String arg = va_arg(argList, String);
		if (arg == NULL) break;
		XmdBufferPush(buffer, &arg);
	}
	
	va_end(argList);
	String *args = XmdBufferBreak(buffer);
	FILE* pipe = XmdPipedExecPath(file, child, mode, args);
	XtFree((char *)(args));
	return pipe;
}

FILE *XmdPipedExecPath (
	ConstString file, pid_t *child, String mode,
	const String argv[]
) {
	int pipes[2];
	pipe(pipes);
	
	pid_t pid = fork();
	switch (pid) {
	case -1: /* fail */
		return NULL;
	case 0: /* child */
		dup2(pipes[1], STDOUT_FILENO);
		close(pipes[0]);
		close(pipes[1]);
		execvp(file, argv);
		exit(EXIT_FAILURE);
		return NULL;
	default: /* parent */
		close(pipes[1]);
		*child = pid;
		return fdopen(pipes[0], mode);
	}
}