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