Geografic-Information-System/lib/gis/popen.c

#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <stdlib.h>
#include <sys/types.h>


#ifdef __MINGW32__
#  include <io.h>
#  include <fcntl.h>
#  include <process.h>
#else
#  include <sys/wait.h>
#  define tst(a,b)        (*mode == 'r'? (b) : (a))
#endif

#include <grass/gis.h>


#define READ      0
#define WRITE     1

static int popen_pid[50];


FILE *G_popen(const char *cmd, const char *mode)
{

#ifdef __MINGW32__

    int thepipes[2];
    FILE *rv = NULL;

    fflush(stdout);
    fflush(stderr);

    /*setvbuf ( stdout, NULL, _IONBF, 0 ); */

    if (_pipe(thepipes, 256, O_BINARY) != -1) {
	execl("cmd", "cmd", "/c", cmd, (char *)NULL);
	close(thepipes[WRITE]);
	rv = fdopen(thepipes[READ], mode);
    }

    return (rv);

#else /* __MINGW32__ */

    int p[2];
    int me, you, pid;

    fflush(stdout);
    fflush(stderr);

    if (pipe(p) < 0)
	return NULL;
    me = tst(p[WRITE], p[READ]);
    you = tst(p[READ], p[WRITE]);
    if ((pid = fork()) == 0) {
	/* me and you reverse roles in child */
	close(me);
	close(tst(0, 1));
	dup(you);
	close(you);
	execl("/bin/sh", "sh", "-c", cmd, (char *)NULL);
	_exit(1);
    }

    if (pid == -1)
	return NULL;
    popen_pid[me] = pid;
    close(you);

    return (fdopen(me, mode));

#endif /* __MINGW32__ */

}

int G_pclose(FILE * ptr)
{
    RETSIGTYPE(*sigint) ();
#ifdef SIGHUP
    RETSIGTYPE(*sighup) ();
#endif
#ifdef SIGQUIT
    RETSIGTYPE(*sigquit) ();
#endif
    int f;

#ifndef __MINGW32__
    int r;
#endif
    int status;

    f = fileno(ptr);
    fclose(ptr);

    sigint = signal(SIGINT, SIG_IGN);
#ifdef __MINGW32__
    _cwait(&status, popen_pid[f], WAIT_CHILD);
    if (0 & status) {
	status = -1;
    }
#else

#ifdef SIGQUIT
    sigquit = signal(SIGQUIT, SIG_IGN);
#endif
#ifdef SIGHUP
    sighup = signal(SIGHUP, SIG_IGN);
#endif
    while ((r = wait(&status)) != popen_pid[f] && r != -1) ;
    if (r == -1)
	status = -1;

#endif /* __MINGW32__ */

    signal(SIGINT, sigint);

#ifdef SIGQUIT
    signal(SIGQUIT, sigquit);
#endif
#ifdef SIGHUP
    signal(SIGHUP, sighup);
#endif

    return (status);
}