/*
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
* Copyright (c) 2004 The DragonFly Project. All rights reserved.
*
* This code is derived from software written by Ken Arnold and
* published in UNIX Review, Vol. 6, No. 8.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD: src/lib/libc/gen/popen.c,v 1.14 2000/01/27 23:06:19 jasone Exp $
* $DragonFly: src/lib/libc/gen/popen.c,v 1.3 2004/06/06 15:05:55 hmp Exp $
* $Id: popen.c,v 1.8 2005/08/08 00:18:22 cpressey Exp $
*
* @(#)popen.c 8.3 (Berkeley) 5/3/95
*
* A modified version of the standard popen()/pclose() functions
* which adds a third function, pgetpid(), which allows the program
* which used popen() to obtain the pid of the process on the other
* end of the pipe.
*/
#include <sys/param.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/time.h>
#include <errno.h>
#include <signal.h>
#include <stdarg.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "popen.h"
extern char **environ;
static struct pid {
struct pid *next;
FILE *fp;
pid_t pid;
} *pidlist;
#ifndef __DECONST
#define __DECONST(type, var) var
#endif
FILE *
aura_popen(const char *fmt, const char *type, ...)
{
FILE *iop;
struct pid *cur;
struct pid *p;
va_list args;
char *command;
const char *argv[4];
int pdes[2], pid;
volatile enum { READ, WRITE, TWO_WAY } pipedir;
/*
* Lite2 introduced two-way popen() pipes using socketpair().
* FreeBSD's pipe() is bidirectional, so we use that.
*/
if (strchr(type, '+')) {
pipedir = TWO_WAY;
} else {
if (type[1] != '\0')
return(NULL);
if (*type == 'r')
pipedir = READ;
else if (*type == 'w')
pipedir = WRITE;
else
return(NULL);
}
if (pipe(pdes) < 0)
return(NULL);
if ((cur = malloc(sizeof(struct pid))) == NULL) {
close(pdes[0]);
close(pdes[1]);
return(NULL);
}
va_start(args, type);
vasprintf(&command, fmt, args);
va_end(args);
argv[0] = "sh";
argv[1] = "-c";
argv[2] = command;
argv[3] = NULL;
switch (pid = vfork()) {
case -1: /* Error. */
close(pdes[0]);
close(pdes[1]);
free(cur);
free(command);
return(NULL);
/* NOTREACHED */
case 0: /* Child. */
if (pipedir == READ || pipedir == TWO_WAY) {
/*
* The dup2() to STDIN_FILENO is repeated to avoid
* writing to pdes[1], which might corrupt the
* parent's copy. This isn't good enough in
* general, since the _exit() is no return, so
* the compiler is free to corrupt all the local
* variables.
*/
close(pdes[0]);
if (pdes[1] != STDOUT_FILENO) {
dup2(pdes[1], STDOUT_FILENO);
close(pdes[1]);
if (pipedir == TWO_WAY)
dup2(STDOUT_FILENO, STDIN_FILENO);
} else if (pipedir == TWO_WAY &&
(pdes[1] != STDIN_FILENO)) {
dup2(pdes[1], STDIN_FILENO);
}
} else {
if (pdes[0] != STDIN_FILENO) {
dup2(pdes[0], STDIN_FILENO);
close(pdes[0]);
}
close(pdes[1]);
}
for (p = pidlist; p; p = p->next) {
close(fileno(p->fp));
}
execve(_PATH_BSHELL, __DECONST(char **, argv), environ);
_exit(127);
/* NOTREACHED */
}
/* Parent; assume fdopen can't fail. */
if (pipedir == READ || pipedir == TWO_WAY) {
iop = fdopen(pdes[0], type);
close(pdes[1]);
} else {
iop = fdopen(pdes[1], type);
close(pdes[0]);
}
/* Link into list of file descriptors. */
cur->fp = iop;
cur->pid = pid;
cur->next = pidlist;
pidlist = cur;
free(command);
return(iop);
}
/*
* pclose --
* Pclose returns -1 if stream is not associated with a `popened' command,
* if already `pclosed', or waitpid returns an error.
*/
int
aura_pclose(FILE *iop)
{
struct pid *cur, *last;
int pstat;
pid_t pid;
/* Find the appropriate file pointer. */
for (last = NULL, cur = pidlist; cur; last = cur, cur = cur->next) {
if (cur->fp == iop)
break;
}
if (cur == NULL)
return (-1);
fclose(iop);
do {
pid = wait4(cur->pid, &pstat, 0, (struct rusage *)0);
} while (pid == -1 && errno == EINTR);
/* Remove the entry from the linked list. */
if (last == NULL)
pidlist = cur->next;
else
last->next = cur->next;
free(cur);
return (pid == -1 ? -1 : pstat);
}
pid_t
aura_pgetpid(FILE *iop)
{
struct pid *cur, *last;
/* Find the appropriate file pointer. */
for (last = NULL, cur = pidlist; cur; last = cur, cur = cur->next)
if (cur->fp == iop)
break;
if (cur == NULL)
return (-1);
return(cur->pid);
}
/*
* Returns:
* 1 if all went well.
* 0 if an error occurred, in which case err is set to:
* AURA_PGETS_TIMEOUT: select() timed out.
* AURA_PGETS_SELECT_ERR: a select() error occurred.
* AURA_PGETS_EOF: end of file condition on pipe.
* AURA_PGETS_FGETS_ERR: a fgets() error occurred.
*/
int
aura_pgets(FILE *p, char *buf, size_t len, long msec, int *err)
{
struct timeval tv;
struct timeval *tvp;
fd_set r;
int n;
tv.tv_sec = msec / 1000;
tv.tv_usec = (msec % 1000) * 1000;
tvp = (msec < 0 ? NULL : &tv);
FD_ZERO(&r);
FD_SET(fileno(p), &r);
*err = 0;
buf[0] = '\0';
if (feof(p)) {
*err = AURA_PGETS_EOF;
return(0);
}
if (ferror(p)) {
*err = AURA_PGETS_FGETS_ERR;
return(0);
}
n = select(fileno(p) + 1, &r, NULL, NULL, tvp);
if (n == 0) {
*err = AURA_PGETS_TIMEOUT;
return(0);
} else if (n < 0) {
*err = AURA_PGETS_SELECT_ERR;
return(0);
} else {
/* Data came in; read it. */
if (fgets(buf, len, p) == NULL) {
if (feof(p)) {
*err = AURA_PGETS_EOF;
} else {
*err = AURA_PGETS_FGETS_ERR;
}
return(0);
} else {
return(1);
}
}
}
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