tests/zfs-tests/cmd/rm_lnkcnt_zero_file/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 http://www.opensolaris.org/os/licensing.
  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 #include <strings.h>
  49
  50 static const int TRUE = 1;
  51 static char *filebase;
  52
  53 static int
  54 pickidx(void)
  55 {
  56         return (random() % 1000);
  57 }
  58
  59 /* ARGSUSED */
  60 static void *
  61 mover(void *a)
  62 {
  63         char buf[256];
  64         int idx, len, ret;
  65
  66         len = strlen(filebase) + 5;
  67
  68         while (TRUE) {
  69                 idx = pickidx();
  70                 (void) snprintf(buf, len, "%s.%03d", filebase, idx);
  71                 ret = rename(filebase, buf);
  72                 if (ret < 0 && errno != ENOENT)
  73                         (void) perror("renaming file");
  74         }
  75
  76         return (NULL);
  77 }
  78
  79 /* ARGSUSED */
  80 static void *
  81 cleaner(void *a)
  82 {
  83         char buf[256];
  84         int idx, len, ret;
  85
  86         len = strlen(filebase) + 5;
  87
  88         while (TRUE) {
  89                 idx = pickidx();
  90                 (void) snprintf(buf, len, "%s.%03d", filebase, idx);
  91                 ret = remove(buf);
  92                 if (ret < 0 && errno != ENOENT)
  93                         (void) perror("removing file");
  94         }
  95
  96         return (NULL);
  97 }
  98
  99 static void *
 100 writer(void *a)
 101 {
 102         int *fd = (int *)a;
 103         int ret;
 104
 105         while (TRUE) {
 106                 if (*fd != -1)
 107                         (void) close (*fd);
 108
 109                 *fd = open(filebase, O_APPEND | O_RDWR | O_CREAT, 0644);
 110                 if (*fd == -1) {
 111                         perror("fail to open test file, refreshing it");
 112                         continue;
 113                 }
 114
 115                 ret = write(*fd, "test\n", 5);
 116                 if (ret != 5)
 117                         perror("writing file");
 118         }
 119
 120         return (NULL);
 121 }
 122
 123 int
 124 main(int argc, char **argv)
 125 {
 126         int fd;
 127         pthread_t tid;
 128
 129         if (argc == 1) {
 130                 (void) printf("Usage: %s <filebase>\n", argv[0]);
 131                 exit(-1);
 132         }
 133
 134         filebase = argv[1];
 135         fd = open(filebase, O_APPEND | O_RDWR | O_CREAT, 0644);
 136         if (fd < 0) {
 137                 perror("creating test file");
 138                 exit(-1);
 139         }
 140
 141         (void) pthread_setconcurrency(4);       /* 3 threads + main */
 142         (void) pthread_create(&tid, NULL, mover, NULL);
 143         (void) pthread_create(&tid, NULL, cleaner, NULL);
 144         (void) pthread_create(&tid, NULL, writer, (void *) &fd);
 145
 146         while (TRUE) {
 147                 int ret;
 148                 struct stat st;
 149
 150                 ret = stat(filebase, &st);
 151                 if (ret == 0 && (st.st_nlink > 2 || st.st_nlink < 1)) {
 152                         (void) printf("st.st_nlink = %d, exiting\n", \
 153                             (int)st.st_nlink);
 154                         exit(0);
 155                 }
 156                 (void) sleep(1);
 157         }
 158
 159         return (0);
 160 }