1 /* $NetBSD: popen.c,v 1.1 1999/09/30 09:23:23 tron Exp $ */ 2 3 /*- 4 * Copyright (c) 1999 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matthias Scheler. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/param.h> 40 41 #include <err.h> 42 #include <errno.h> 43 #include <paths.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <time.h> 47 #include <unistd.h> 48 49 #define _PATH_CAT "/bin/cat" 50 #define BUFSIZE (640*1024) 51 /* 640KB ought to be enough for everyone. */ 52 #define DATAFILE "popen.data" 53 54 int 55 main(int argc, char **argv) 56 { 57 char *buffer, command[MAXPATHLEN]; 58 int index, in; 59 FILE *pipe; 60 61 if ((buffer = malloc(BUFSIZE*sizeof(char))) == NULL) 62 err(1, NULL); 63 64 for (index=0; index<BUFSIZE; index++) 65 buffer[index]=arc4random(); 66 67 (void)snprintf(command, sizeof(command), "%s >%s", 68 _PATH_CAT, DATAFILE); 69 if ((pipe = popen(command, "w")) == NULL) 70 err(1, "popen write"); 71 72 if (fwrite(buffer, sizeof(char), BUFSIZE, pipe) != BUFSIZE) 73 err(1, "write"); 74 75 if (pclose(pipe) == -1) 76 err(1, "pclose"); 77 78 (void)snprintf(command, sizeof(command), "%s %s", 79 _PATH_CAT, DATAFILE); 80 if ((pipe = popen(command, "r")) == NULL) 81 err(1, "popen read"); 82 83 index = 0; 84 while ((in = fgetc(pipe)) != EOF) 85 if (index == BUFSIZE) { 86 errno = EFBIG; 87 err(1, "read"); 88 } 89 else 90 if ((char)in != buffer[index++]) { 91 errno = EINVAL; 92 err(1, "read"); 93 } 94 95 if (index < BUFSIZE) { 96 errno = EIO; 97 err(1, "read"); 98 } 99 100 if (pclose(pipe) == -1) 101 err(1, "pclose"); 102 103 (void)unlink(DATAFILE); 104 return 0; 105 } 106