Loading...
gen/popen.c /dev/null Libc-262
--- /dev/null
+++ Libc/Libc-262/gen/popen.c
@@ -0,0 +1,205 @@
+/*
+ * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License").  You may not use this file except in compliance with the
+ * License.  Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
+ *
+ * This Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+/*
+ * Copyright (c) 1988, 1993
+ *	The Regents of the University of California.  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.
+ */
+
+#include <sys/param.h>
+#include <sys/wait.h>
+#include <sys/socket.h>
+
+#include <signal.h>
+#include <errno.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <paths.h>
+#include <crt_externs.h>
+
+#define environ *(_NSGetEnviron())
+
+static struct pid {
+	struct pid *next;
+	FILE *fp;
+	pid_t pid;
+} *pidlist; 
+	
+FILE *
+popen(command, type)
+	const char *command, *type;
+{
+	struct pid *cur;
+	FILE *iop;
+	int pdes[2], pid, twoway;
+	char *argv[4];
+	struct pid *p;
+
+	if (strchr(type, '+')) {
+		twoway = 1;
+		type = "r+";
+                if (socketpair(AF_UNIX, SOCK_STREAM, 0, pdes) < 0)
+                        return (NULL);
+	} else  {
+		twoway = 0;
+		if ((*type != 'r' && *type != 'w') || type[1])
+			return (NULL);
+	}
+	if (pipe(pdes) < 0)
+		return (NULL);
+
+	if ((cur = malloc(sizeof(struct pid))) == NULL) {
+		(void)close(pdes[0]);
+		(void)close(pdes[1]);
+		return (NULL);
+	}
+
+	argv[0] = "sh";
+	argv[1] = "-c";
+	argv[2] = (char *)command;
+	argv[3] = NULL;
+
+	switch (pid = vfork()) {
+	case -1:			/* Error. */
+		(void)close(pdes[0]);
+		(void)close(pdes[1]);
+		free(cur);
+		return (NULL);
+		/* NOTREACHED */
+	case 0:				/* Child. */
+		if (*type == 'r') {
+			/*
+			 * 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.
+			 */
+			(void)close(pdes[0]);
+			if (pdes[1] != STDOUT_FILENO) {
+				(void)dup2(pdes[1], STDOUT_FILENO);
+				(void)close(pdes[1]);
+				if (twoway)
+					(void)dup2(STDOUT_FILENO, STDIN_FILENO);
+			} else if (twoway && (pdes[1] != STDIN_FILENO))
+				(void)dup2(pdes[1], STDIN_FILENO);
+		} else {
+			if (pdes[0] != STDIN_FILENO) {
+				(void)dup2(pdes[0], STDIN_FILENO);
+				(void)close(pdes[0]);
+			}
+			(void)close(pdes[1]);
+			}
+		for (p = pidlist; p; p = p->next) {
+			(void)close(fileno(p->fp));
+		}
+		execve(_PATH_BSHELL, argv, environ);
+		_exit(127);
+		/* NOTREACHED */
+	}
+
+	/* Parent; assume fdopen can't fail. */
+	if (*type == 'r') {
+		iop = fdopen(pdes[0], type);
+		(void)close(pdes[1]);
+	} else {
+		iop = fdopen(pdes[1], type);
+		(void)close(pdes[0]);
+	}
+
+	/* Link into list of file descriptors. */
+	cur->fp = iop;
+	cur->pid =  pid;
+	cur->next = pidlist;
+	pidlist = cur;
+
+	return (iop);
+}
+
+/*
+ * pclose --
+ *	Pclose returns -1 if stream is not associated with a `popened' command,
+ *	if already `pclosed', or waitpid returns an error.
+ */
+int
+pclose(iop)
+	FILE *iop;
+{
+	register 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);
+
+	(void)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);
+}