source: MondoRescue/branches/2.2.9/mindi-busybox/archival/libunarchive/open_transformer.c@ 3320

/* vi: set sw=4 ts=4: */
/*
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include "libbb.h"
#include "unarchive.h"

/* transformer(), more than meets the eye */
/*
 * On MMU machine, the transform_prog and ... are stripped
 * by a macro in include/unarchive.h. On NOMMU, transformer is stripped.
 */
int open_transformer(int src_fd,
    USE_DESKTOP(long long) int (*transformer)(int src_fd, int dst_fd),
    const char *transform_prog, ...)
{
    int fd_pipe[2];
    int pid;

    xpipe(fd_pipe);

#if BB_MMU
    pid = fork();
#else
    pid = vfork();
#endif
    if (pid == -1)
        bb_perror_msg_and_die("fork failed");

    if (pid == 0) {
#if !BB_MMU
        va_list ap;
#endif
        /* child process */
        close(fd_pipe[0]); /* We don't wan't to read from the parent */
        // FIXME: error check?
#if BB_MMU
        transformer(src_fd, fd_pipe[1]);
        if (ENABLE_FEATURE_CLEAN_UP) {
            close(fd_pipe[1]); /* Send EOF */
            close(src_fd);
        }
        exit(0);
#else
        xmove_fd(src_fd, 0);
        xmove_fd(fd_pipe[1], 1);
        va_start(ap, transform_prog);
        BB_EXECVP(transform_prog, ap);
        bb_perror_and_die("exec failed");
#endif
        /* notreached */
    }

    /* parent process */
    close(fd_pipe[1]); /* Don't want to write to the child */

    return fd_pipe[0];
}