1/* 2 * $OpenBSD: dup2test.c,v 1.3 2003/07/31 21:48:08 deraadt Exp $ 3 * $OpenBSD: dup2_self.c,v 1.3 2003/07/31 21:48:08 deraadt Exp $ 4 * $OpenBSD: fcntl_dup.c,v 1.2 2003/07/31 21:48:08 deraadt Exp $ 5 * 6 * Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain. 7 * 8 * $FreeBSD$ 9 */ 10 11/* 12 * Test #1: check if dup(2) works. 13 * Test #2: check if dup2(2) works. 14 * Test #3: check if dup2(2) returned a fd we asked for. 15 * Test #4: check if dup2(2) cleared close-on-exec flag for duped fd. 16 * Test #5: check if dup2(2) allows to dup fd to itself. 17 * Test #6: check if dup2(2) returned a fd we asked for. 18 * Test #7: check if dup2(2) did not clear close-on-exec flag for duped fd. 19 * Test #8: check if fcntl(F_DUPFD) works. 20 * Test #9: check if fcntl(F_DUPFD) cleared close-on-exec flag for duped fd. 21 * Test #10: check if dup2() to a fd > current maximum number of open files 22 * limit work. 23 * Test #11: check if fcntl(F_DUP2FD) works. 24 * Test #12: check if fcntl(F_DUP2FD) returned a fd we asked for. 25 * Test #13: check if fcntl(F_DUP2FD) cleared close-on-exec flag for duped fd. 26 * Test #14: check if fcntl(F_DUP2FD) allows to dup fd to itself. 27 * Test #15: check if fcntl(F_DUP2FD) returned a fd we asked for. 28 * Test #16: check if fcntl(F_DUP2FD) did not clear close-on-exec flag for 29 * duped fd. 30 * Test #17: check if fcntl(F_DUP2FD) to a fd > current maximum number of open 31 * files limit work. 32 */ 33 34#include <sys/types.h> 35#include <sys/time.h> 36#include <sys/resource.h> 37 38#include <err.h> 39#include <fcntl.h> 40#include <stdio.h> 41#include <stdlib.h> 42#include <unistd.h> 43 44static int getafile(void); 45 46static int 47getafile(void) 48{ 49 int fd; 50 51 char temp[] = "/tmp/dup2XXXXXXXXX"; 52 if ((fd = mkstemp(temp)) < 0) 53 err(1, "mkstemp"); 54 remove(temp); 55 if (ftruncate(fd, 1024) != 0) 56 err(1, "ftruncate"); 57 return (fd); 58} 59 60int 61main(int __unused argc, char __unused *argv[]) 62{ 63 struct rlimit rlp; 64 int orgfd, fd1, fd2, test = 0; 65 66 orgfd = getafile(); 67 68 printf("1..17\n"); 69 70 /* If dup(2) ever work? */ 71 if ((fd1 = dup(orgfd)) < 0) 72 err(1, "dup"); 73 printf("ok %d - dup(2) works\n", ++test); 74 75 /* Set close-on-exec */ 76 if (fcntl(fd1, F_SETFD, 1) != 0) 77 err(1, "fcntl(F_SETFD)"); 78 79 /* If dup2(2) ever work? */ 80 if ((fd2 = dup2(fd1, fd1 + 1)) < 0) 81 err(1, "dup2"); 82 printf("ok %d - dup2(2) works\n", ++test); 83 84 /* Do we get the right fd? */ 85 ++test; 86 if (fd2 != fd1 + 1) 87 printf("no ok %d - dup2(2) didn't give us the right fd\n", 88 test); 89 else 90 printf("ok %d - dup2(2) returned a correct fd\n", test); 91 92 /* Was close-on-exec cleared? */ 93 ++test; 94 if (fcntl(fd2, F_GETFD) != 0) 95 printf("not ok %d - dup2(2) didn't clear close-on-exec\n", 96 test); 97 else 98 printf("ok %d - dup2(2) cleared close-on-exec\n", test); 99 100 /* 101 * Dup to itself. 102 * 103 * We're testing a small tweak in dup2 semantics. 104 * Normally dup and dup2 will clear the close-on-exec 105 * flag on the new fd (which appears to be an implementation 106 * mistake from start and not some planned behavior). 107 * In todays implementations of dup and dup2 we have to make 108 * an effort to really clear that flag. But all tested 109 * implementations of dup2 have another tweak. If we 110 * dup2(old, new) when old == new, the syscall short-circuits 111 * and returns early (because there is no need to do all the 112 * work (and there is a risk for serious mistakes)). 113 * So although the docs say that dup2 should "take 'old', 114 * close 'new' perform a dup(2) of 'old' into 'new'" 115 * the docs are not really followed because close-on-exec 116 * is not cleared on 'new'. 117 * 118 * Since everyone has this bug, we pretend that this is 119 * the way it is supposed to be and test here that it really 120 * works that way. 121 * 122 * This is a fine example on where two separate implementation 123 * fuckups take out each other and make the end-result the way 124 * it was meant to be. 125 */ 126 if ((fd2 = dup2(fd1, fd1)) < 0) 127 err(1, "dup2"); 128 printf("ok %d - dup2(2) to itself works\n", ++test); 129 130 /* Do we get the right fd? */ 131 ++test; 132 if (fd2 != fd1) 133 printf("not ok %d - dup2(2) didn't give us the right fd\n", 134 test); 135 else 136 printf("ok %d - dup2(2) to itself returned a correct fd\n", 137 test); 138 139 /* Was close-on-exec cleared? */ 140 ++test; 141 if (fcntl(fd2, F_GETFD) == 0) 142 printf("not ok %d - dup2(2) cleared close-on-exec\n", test); 143 else 144 printf("ok %d - dup2(2) didn't clear close-on-exec\n", test); 145 146 /* Does fcntl(F_DUPFD) work? */ 147 if ((fd2 = fcntl(fd1, F_DUPFD)) < 0) 148 err(1, "fcntl(F_DUPFD)"); 149 printf("ok %d - fcntl(F_DUPFD) works\n", ++test); 150 151 /* Was close-on-exec cleared? */ 152 ++test; 153 if (fcntl(fd2, F_GETFD) != 0) 154 printf( 155 "not ok %d - fcntl(F_DUPFD) didn't clear close-on-exec\n", 156 test); 157 else 158 printf("ok %d - fcntl(F_DUPFD) cleared close-on-exec\n", test); 159 160 ++test; 161 if (getrlimit(RLIMIT_NOFILE, &rlp) < 0) 162 err(1, "getrlimit"); 163 if ((fd2 = dup2(fd1, rlp.rlim_cur + 1)) >= 0) 164 printf("not ok %d - dup2(2) bypassed NOFILE limit\n", test); 165 else 166 printf("ok %d - dup2(2) didn't bypass NOFILE limit\n", test); 167 168 /* If fcntl(F_DUP2FD) ever work? */ 169 if ((fd2 = fcntl(fd1, F_DUP2FD, fd1 + 1)) < 0) 170 err(1, "fcntl(F_DUP2FD)"); 171 printf("ok %d - fcntl(F_DUP2FD) works\n", ++test); 172 173 /* Do we get the right fd? */ 174 ++test; 175 if (fd2 != fd1 + 1) 176 printf( 177 "no ok %d - fcntl(F_DUP2FD) didn't give us the right fd\n", 178 test); 179 else 180 printf("ok %d - fcntl(F_DUP2FD) returned a correct fd\n", 181 test); 182 183 /* Was close-on-exec cleared? */ 184 ++test; 185 if (fcntl(fd2, F_GETFD) != 0) 186 printf( 187 "not ok %d - fcntl(F_DUP2FD) didn't clear close-on-exec\n", 188 test); 189 else 190 printf("ok %d - fcntl(F_DUP2FD) cleared close-on-exec\n", 191 test); 192 193 /* Dup to itself */ 194 if ((fd2 = fcntl(fd1, F_DUP2FD, fd1)) < 0) 195 err(1, "fcntl(F_DUP2FD)"); 196 printf("ok %d - fcntl(F_DUP2FD) to itself works\n", ++test); 197 198 /* Do we get the right fd? */ 199 ++test; 200 if (fd2 != fd1) 201 printf( 202 "not ok %d - fcntl(F_DUP2FD) didn't give us the right fd\n", 203 test); 204 else 205 printf( 206 "ok %d - fcntl(F_DUP2FD) to itself returned a correct fd\n", 207 test); 208 209 /* Was close-on-exec cleared? */ 210 ++test; 211 if (fcntl(fd2, F_GETFD) == 0) 212 printf("not ok %d - fcntl(F_DUP2FD) cleared close-on-exec\n", 213 test); 214 else 215 printf("ok %d - fcntl(F_DUP2FD) didn't clear close-on-exec\n", 216 test); 217 218 ++test; 219 if (getrlimit(RLIMIT_NOFILE, &rlp) < 0) 220 err(1, "getrlimit"); 221 if ((fd2 = fcntl(fd1, F_DUP2FD, rlp.rlim_cur + 1)) >= 0) 222 printf("not ok %d - fcntl(F_DUP2FD) bypassed NOFILE limit\n", 223 test); 224 else 225 printf("ok %d - fcntl(F_DUP2FD) didn't bypass NOFILE limit\n", 226 test); 227 228 return (0); 229} 230