1 /* 2 * 3 * Copyright (c) International Business Machines Corp., 2001 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 13 * the GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 18 */ 19 20 /* 21 * NAME 22 * read03.c 23 * 24 * DESCRIPTION 25 * Testcase to check that read() sets errno to EAGAIN 26 * 27 * ALGORITHM 28 * Create a named pipe (fifo), open it in O_NONBLOCK mode, and 29 * attempt to read from it, without writing to it. read() should fail 30 * with EAGAIN. 31 * 32 * USAGE: <for command-line> 33 * read03 [-c n] [-e] [-i n] [-I x] [-P x] [-t] 34 * where, -c n : Run n copies concurrently. 35 * -e : Turn on errno logging. 36 * -i n : Execute test n times. 37 * -I x : Execute test for x seconds. 38 * -P x : Pause for x seconds between iterations. 39 * -t : Turn on syscall timing. 40 * 41 * HISTORY 42 * 07/2001 Ported by Wayne Boyer 43 * 44 * RESTRICTIONS 45 * NONE 46 */ 47 #include <sys/stat.h> 48 #include <fcntl.h> 49 #include <signal.h> 50 #include <errno.h> 51 #include "test.h" 52 53 char *TCID = "read03"; 54 int TST_TOTAL = 1; 55 56 char fifo[100] = "fifo"; 57 int rfd, wfd; 58 struct stat buf; 59 60 void alarm_handler(); 61 void setup(); 62 void cleanup(); 63 64 int main(int ac, char **av) 65 { 66 int lc; 67 68 int c; 69 70 tst_parse_opts(ac, av, NULL, NULL); 71 72 setup(); 73 74 /* 75 * The following loop checks looping state if -i option given 76 */ 77 for (lc = 0; TEST_LOOPING(lc); lc++) { 78 /* reset tst_count in case we are looping */ 79 tst_count = 0; 80 81 TEST(read(rfd, &c, 1)); 82 83 if (TEST_RETURN != -1) { 84 tst_resm(TFAIL, "read() failed to fail when nothing " 85 "is written to a pipe"); 86 continue; 87 } 88 89 if (TEST_ERRNO != EAGAIN) { 90 tst_resm(TFAIL, "read set bad errno, expected " 91 "EAGAIN, got %d", TEST_ERRNO); 92 } else { 93 tst_resm(TPASS, "read() succeded in setting errno to " 94 "EAGAIN"); 95 } 96 } 97 cleanup(); 98 tst_exit(); 99 100 } 101 102 /* 103 * setup() - performs all ONE TIME setup for this test 104 */ 105 void setup(void) 106 { 107 108 tst_sig(NOFORK, DEF_HANDLER, cleanup); 109 110 TEST_PAUSE; 111 112 /* create a temporary filename */ 113 sprintf(fifo, "%s.%d", fifo, getpid()); 114 115 /* Create a temporary directory and cd to it */ 116 tst_tmpdir(); 117 118 if (mknod(fifo, S_IFIFO | 0777, 0) < 0) { 119 tst_brkm(TBROK, cleanup, "mknod() failed, errno: %d", errno); 120 } 121 if (stat(fifo, &buf) != 0) { 122 tst_brkm(TBROK, cleanup, "stat() failed, errno: %d", errno); 123 } 124 if ((buf.st_mode & S_IFIFO) == 0) { 125 tst_brkm(TBROK, cleanup, "Mode does not indicate fifo file"); 126 } 127 128 rfd = open(fifo, O_RDONLY | O_NONBLOCK); 129 wfd = open(fifo, O_WRONLY | O_NONBLOCK); 130 } 131 132 /* 133 * cleanup() - performs all ONE TIME cleanup for this test at 134 * completion or premature exit. 135 */ 136 void cleanup(void) 137 { 138 139 close(rfd); 140 close(wfd); 141 unlink(fifo); 142 143 /* delete the test directory created in setup() */ 144 tst_rmdir(); 145 146 } 147
