radare2/libr/cons/pipe.c

/* radare - LGPL - Copyright 2009-2011 pancake<nopcode.org> */

#include <r_cons.h>
#include <unistd.h>
#include <limits.h>

//TODO: cons_pipe should be using a stack pipe_push, pipe_pop
/* this is the base fd.. more than one is supported :) */
static int backup_fd = -1;

R_API int r_cons_pipe_open(const char *file, int append) {
	int fd = open (file, O_RDWR | O_CREAT | (append?O_APPEND:O_TRUNC), 0644);
	if (fd==-1) {
		eprintf ("Cannot open file '%s'\n", file);
		return -1;
	} else eprintf ("%s created\n", file);
	if (backup_fd != -1) {
		close (backup_fd);
	}
#if __WINDOWS__
	backup_fd = 2002-(fd-2); // windows xp has 2048 as limit fd
	if (_dup2 (1, backup_fd) == -1) {
#else
	backup_fd = sysconf (_SC_OPEN_MAX)-(fd-2); // portable getdtablesize()
	if (dup2 (1, backup_fd) == -1) {
#endif
		eprintf ("Cannot dup stdout to %d\n", backup_fd);
		return -1;
	}
	close (1);
	dup2 (fd, 1);
	return fd;
}

R_API void r_cons_pipe_close(int fd) {
	if (fd == -1)
		return;
	close (fd);
	if (backup_fd != -1) {
		dup2 (backup_fd, 1);
		close (backup_fd);
		backup_fd = -1;
	}
}