tests/zfs-tests/cmd/rm_lnkcnt_zero_file.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or https://opensource.org/licenses/CDDL-1.0.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*
  28  * Copyright (c) 2012 by Delphix. All rights reserved.
  29  */
  30
  31 /*
  32  * --------------------------------------------------------------------
  33  * The purpose of this test is to see if the bug reported (#4723351) for
  34  * UFS exists when using a ZFS file system.
  35  * --------------------------------------------------------------------
  36  *
  37  */
  38 #define _REENTRANT 1
  39 #include <stdio.h>
  40 #include <fcntl.h>
  41 #include <pthread.h>
  42 #include <string.h>
  43 #include <errno.h>
  44 #include <sys/types.h>
  45 #include <sys/stat.h>
  46 #include <stdlib.h>
  47 #include <unistd.h>
  48
  49 static char *filebase;
  50
  51 static int
  52 pickidx(void)
  53 {
  54         return (random() % 1000);
  55 }
  56
  57 static void *
  58 mover(void *a)
  59 {
  60         (void) a;
  61         char buf[256];
  62         int idx, len, ret;
  63
  64         len = strlen(filebase) + 5;
  65
  66         for (;;) {
  67                 idx = pickidx();
  68                 (void) snprintf(buf, len, "%s.%03d", filebase, idx);
  69                 ret = rename(filebase, buf);
  70                 if (ret < 0 && errno != ENOENT)
  71                         (void) perror("renaming file");
  72         }
  73
  74         return (NULL);
  75 }
  76
  77 static void *
  78 cleaner(void *a)
  79 {
  80         (void) a;
  81         char buf[256];
  82         int idx, len, ret;
  83
  84         len = strlen(filebase) + 5;
  85
  86         for (;;) {
  87                 idx = pickidx();
  88                 (void) snprintf(buf, len, "%s.%03d", filebase, idx);
  89                 ret = remove(buf);
  90                 if (ret < 0 && errno != ENOENT)
  91                         (void) perror("removing file");
  92         }
  93
  94         return (NULL);
  95 }
  96
  97 static void *
  98 writer(void *a)
  99 {
 100         int *fd = (int *)a;
 101         int ret;
 102
 103         for (;;) {
 104                 if (*fd != -1)
 105                         (void) close (*fd);
 106
 107                 *fd = open(filebase, O_APPEND | O_RDWR | O_CREAT, 0644);
 108                 if (*fd == -1) {
 109                         perror("fail to open test file, refreshing it");
 110                         continue;
 111                 }
 112
 113                 ret = write(*fd, "test\n", 5);
 114                 if (ret != 5)
 115                         perror("writing file");
 116         }
 117
 118         return (NULL);
 119 }
 120
 121 int
 122 main(int argc, char **argv)
 123 {
 124         int fd;
 125         pthread_t tid;
 126
 127         if (argc == 1) {
 128                 (void) printf("Usage: %s <filebase>\n", argv[0]);
 129                 exit(-1);
 130         }
 131
 132         filebase = argv[1];
 133         fd = open(filebase, O_APPEND | O_RDWR | O_CREAT, 0644);
 134         if (fd < 0) {
 135                 perror("creating test file");
 136                 exit(-1);
 137         }
 138
 139         (void) pthread_setconcurrency(4);       /* 3 threads + main */
 140         (void) pthread_create(&tid, NULL, mover, NULL);
 141         (void) pthread_create(&tid, NULL, cleaner, NULL);
 142         (void) pthread_create(&tid, NULL, writer, (void *) &fd);
 143
 144         for (;;) {
 145                 int ret;
 146                 struct stat st;
 147
 148                 ret = stat(filebase, &st);
 149                 if (ret == 0 && (st.st_nlink > 2 || st.st_nlink < 1)) {
 150                         (void) printf("st.st_nlink = %d, exiting\n", \
 151                             (int)st.st_nlink);
 152                         exit(0);
 153                 }
 154                 (void) sleep(1);
 155         }
 156
 157         return (0);
 158 }