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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/param.h> 33 34 #include <err.h> 35 #include <errno.h> 36 #include <paths.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <time.h> 40 #include <unistd.h> 41 42 #define _PATH_CAT "/bin/cat" 43 #define BUFSIZE (640*1024) 44 /* 640KB ought to be enough for everyone. */ 45 #define DATAFILE "popen.data" 46 47 int 48 main(int argc, char **argv) 49 { 50 char *buffer, command[MAXPATHLEN]; 51 int index, in; 52 FILE *pipe; 53 54 if ((buffer = malloc(BUFSIZE*sizeof(char))) == NULL) 55 err(1, NULL); 56 57 for (index=0; index<BUFSIZE; index++) 58 buffer[index]=arc4random(); 59 60 (void)snprintf(command, sizeof(command), "%s >%s", 61 _PATH_CAT, DATAFILE); 62 if ((pipe = popen(command, "w")) == NULL) 63 err(1, "popen write"); 64 65 if (fwrite(buffer, sizeof(char), BUFSIZE, pipe) != BUFSIZE) 66 err(1, "write"); 67 68 if (pclose(pipe) == -1) 69 err(1, "pclose"); 70 71 (void)snprintf(command, sizeof(command), "%s %s", 72 _PATH_CAT, DATAFILE); 73 if ((pipe = popen(command, "r")) == NULL) 74 err(1, "popen read"); 75 76 index = 0; 77 while ((in = fgetc(pipe)) != EOF) 78 if (index == BUFSIZE) { 79 errno = EFBIG; 80 err(1, "read"); 81 } 82 else 83 if ((char)in != buffer[index++]) { 84 errno = EINVAL; 85 err(1, "read"); 86 } 87 88 if (index < BUFSIZE) { 89 errno = EIO; 90 err(1, "read"); 91 } 92 93 if (pclose(pipe) == -1) 94 err(1, "pclose"); 95 96 (void)unlink(DATAFILE); 97 return 0; 98 } 99