tests/zfs-tests/cmd/largest_file/largest_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 #include "../file_common.h"
  32 #include <sys/param.h>
  33 #include <signal.h>
  34 #include <stdio.h>
  35 #include <string.h>
  36 #include <sys/stdtypes.h>
  37 #include <unistd.h>
  38
  39 /*
  40  * --------------------------------------------------------------
  41  *
  42  *      Assertion:
  43  *              The last byte of the largest file size can be
  44  *              accessed without any errors.  Also, the writing
  45  *              beyond the last byte of the largest file size
  46  *              will produce an errno of EFBIG.
  47  *
  48  * --------------------------------------------------------------
  49  *      If the write() system call below returns a "1",
  50  *      then the last byte can be accessed.
  51  * --------------------------------------------------------------
  52  */
  53 static void     sigxfsz(int);
  54 static void     usage(char *);
  55
  56 int
  57 main(int argc, char **argv)
  58 {
  59         int             fd = 0;
  60         offset_t        offset = (MAXOFFSET_T - 1);
  61         offset_t        llseek_ret = 0;
  62         int             write_ret = 0;
  63         int             err = 0;
  64         char            mybuf[5] = "aaaa\0";
  65         char            *testfile;
  66         mode_t          mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH;
  67         struct sigaction sa;
  68
  69         if (argc != 2) {
  70                 usage(argv[0]);
  71         }
  72
  73         if (sigemptyset(&sa.sa_mask) == -1)
  74                 return (errno);
  75         sa.sa_flags = 0;
  76         sa.sa_handler = sigxfsz;
  77         if (sigaction(SIGXFSZ, &sa, NULL) == -1)
  78                 return (errno);
  79
  80         testfile = strdup(argv[1]);
  81
  82         fd = open(testfile, O_CREAT | O_RDWR, mode);
  83         if (fd < 0) {
  84                 err = errno;
  85                 perror("Failed to create testfile");
  86                 free(testfile);
  87                 return (err);
  88         }
  89
  90         llseek_ret = lseek64(fd, offset, SEEK_SET);
  91         if (llseek_ret < 0) {
  92                 err = errno;
  93                 perror("Failed to seek to end of testfile");
  94                 goto out;
  95         }
  96
  97         write_ret = write(fd, mybuf, 1);
  98         if (write_ret < 0) {
  99                 err = errno;
 100                 perror("Failed to write to end of file");
 101                 goto out;
 102         }
 103
 104         offset = 0;
 105         llseek_ret = lseek64(fd, offset, SEEK_CUR);
 106         if (llseek_ret < 0) {
 107                 err = errno;
 108                 perror("Failed to seek to end of file");
 109                 goto out;
 110         }
 111
 112         write_ret = write(fd, mybuf, 1);
 113         if (write_ret < 0) {
 114                 if (errno == EFBIG || errno == EINVAL) {
 115                         (void) printf("write errno=EFBIG|EINVAL: success\n");
 116                         err = 0;
 117                 } else {
 118                         err = errno;
 119                         perror("Did not receive EFBIG");
 120                 }
 121         } else {
 122                 (void) printf("write completed successfully, test failed\n");
 123                 err = 1;
 124         }
 125
 126 out:
 127         (void) unlink(testfile);
 128         free(testfile);
 129         close(fd);
 130         return (err);
 131 }
 132
 133 static void
 134 usage(char *name)
 135 {
 136         (void) printf("%s <testfile>\n", name);
 137         exit(1);
 138 }
 139
 140 /* ARGSUSED */
 141 static void
 142 sigxfsz(int signo)
 143 {
 144         (void) printf("\nlargest_file: sigxfsz() caught SIGXFSZ\n");
 145 }