123 lines
2.2 KiB
C
123 lines
2.2 KiB
C
|
/*
|
||
|
|
* popen - open a pipe
|
||
|
|
*/
|
||
|
|
/* $Header$ */
|
||
|
|
|
||
|
|
#include <sys/types.h>
|
||
|
|
#include <limits.h>
|
||
|
|
#include <errno.h>
|
||
|
|
#include <signal.h>
|
||
|
|
#include <stdio.h>
|
||
|
|
|
||
|
|
#if defined(__BSD4_2)
|
||
|
|
union wait {
|
||
|
|
int w_status;
|
||
|
|
};
|
||
|
|
typedef union wait wait_arg;
|
||
|
|
#else
|
||
|
|
typedef int wait_arg;
|
||
|
|
#endif /* __BSD4_2 */
|
||
|
|
|
||
|
|
#include "../stdio/loc_incl.h"
|
||
|
|
|
||
|
|
#ifdef _ANSI
|
||
|
|
int _close(int d);
|
||
|
|
int _dup2(int oldd, int newd); /* not present in System 5 */
|
||
|
|
int _execl(const char *name, const char *_arg, ... );
|
||
|
|
pid_t _fork(void);
|
||
|
|
int _pipe(int fildes[2]);
|
||
|
|
pid_t _wait(wait_arg *status);
|
||
|
|
void _exit(int status);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
static int pids[OPEN_MAX];
|
||
|
|
|
||
|
|
FILE *
|
||
|
|
popen(command, type)
|
||
|
|
_CONST char *command;
|
||
|
|
_CONST char *type;
|
||
|
|
{
|
||
|
|
int piped[2];
|
||
|
|
int Xtype = *type == 'r' ? 0 : *type == 'w' ? 1 : 2;
|
||
|
|
int pid;
|
||
|
|
|
||
|
|
if (Xtype == 2 ||
|
||
|
|
_pipe(piped) < 0 ||
|
||
|
|
(pid = _fork()) < 0) return 0;
|
||
|
|
|
||
|
|
if (pid == 0) {
|
||
|
|
/* child */
|
||
|
|
register int *p;
|
||
|
|
|
||
|
|
for (p = pids; p < &pids[OPEN_MAX]; p++) {
|
||
|
|
if (*p) _close((int)(p - pids));
|
||
|
|
}
|
||
|
|
_close(piped[Xtype]);
|
||
|
|
_dup2(piped[!Xtype], !Xtype);
|
||
|
|
_close(piped[!Xtype]);
|
||
|
|
_execl("/bin/sh", "sh", "-c", command, (char *) 0);
|
||
|
|
_exit(127); /* like system() ??? */
|
||
|
|
}
|
||
|
|
|
||
|
|
pids[piped[Xtype]] = pid;
|
||
|
|
_close(piped[!Xtype]);
|
||
|
|
return fdopen(piped[Xtype], type);
|
||
|
|
}
|
||
|
|
|
||
|
|
#if defined(__BSD4_2)
|
||
|
|
#define ret_val status.w_status
|
||
|
|
#else
|
||
|
|
#define ret_val status
|
||
|
|
#endif
|
||
|
|
|
||
|
|
int
|
||
|
|
pclose(stream)
|
||
|
|
FILE *stream;
|
||
|
|
{
|
||
|
|
int fd = fileno(stream);
|
||
|
|
wait_arg status;
|
||
|
|
int wret;
|
||
|
|
|
||
|
|
#ifdef _ANSI
|
||
|
|
void (*intsave)(int) = signal(SIGINT, SIG_IGN);
|
||
|
|
void (*quitsave)(int) = signal(SIGQUIT, SIG_IGN);
|
||
|
|
#else
|
||
|
|
void (*intsave)() = signal(SIGINT, SIG_IGN);
|
||
|
|
void (*quitsave)() = signal(SIGQUIT, SIG_IGN);
|
||
|
|
#endif
|
||
|
|
fclose(stream);
|
||
|
|
while ((wret = _wait(&status)) != -1) {
|
||
|
|
if (wret == pids[fd]) break;
|
||
|
|
}
|
||
|
|
if (wret == -1) ret_val = -1;
|
||
|
|
signal(SIGINT, intsave);
|
||
|
|
signal(SIGQUIT, quitsave);
|
||
|
|
pids[fd] = 0;
|
||
|
|
return ret_val;
|
||
|
|
}
|
||
|
|
|
||
|
|
#if defined(__USG)
|
||
|
|
int _dup(int fildes);
|
||
|
|
|
||
|
|
static int
|
||
|
|
_dup2(oldd, newd)
|
||
|
|
int oldd, newd;
|
||
|
|
{
|
||
|
|
int i = 0, fd, tmp;
|
||
|
|
int fdbuf[_NFILES];
|
||
|
|
|
||
|
|
/* ignore the error on the close() */
|
||
|
|
tmp = errno; (void) _close(newd); errno = tmp;
|
||
|
|
while ((fd = _dup(oldd)) != newd) {
|
||
|
|
if (fd == -1) break;
|
||
|
|
fdbuf[i++] = fd;
|
||
|
|
}
|
||
|
|
tmp = errno;
|
||
|
|
while (--i >= 0) {
|
||
|
|
_close(fdbuf[i]);
|
||
|
|
}
|
||
|
|
errno = tmp;
|
||
|
|
return -(fd == -1);
|
||
|
|
}
|
||
|
|
#endif /* __USG */
|