tests/zfs-tests/cmd/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 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 #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         if (testfile == NULL)
  82                 return (errno);
  83
  84         fd = open(testfile, O_CREAT | O_RDWR, mode);
  85         if (fd < 0) {
  86                 err = errno;
  87                 perror("Failed to create testfile");
  88                 free(testfile);
  89                 return (err);
  90         }
  91
  92         llseek_ret = lseek64(fd, offset, SEEK_SET);
  93         if (llseek_ret < 0) {
  94                 err = errno;
  95                 perror("Failed to seek to end of testfile");
  96                 goto out;
  97         }
  98
  99         write_ret = write(fd, mybuf, 1);
 100         if (write_ret < 0) {
 101                 err = errno;
 102                 perror("Failed to write to end of file");
 103                 goto out;
 104         }
 105
 106         offset = 0;
 107         llseek_ret = lseek64(fd, offset, SEEK_CUR);
 108         if (llseek_ret < 0) {
 109                 err = errno;
 110                 perror("Failed to seek to end of file");
 111                 goto out;
 112         }
 113
 114         write_ret = write(fd, mybuf, 1);
 115         if (write_ret < 0) {
 116                 if (errno == EFBIG || errno == EINVAL) {
 117                         (void) printf("write errno=EFBIG|EINVAL: success\n");
 118                         err = 0;
 119                 } else {
 120                         err = errno;
 121                         perror("Did not receive EFBIG");
 122                 }
 123         } else {
 124                 (void) printf("write completed successfully, test failed\n");
 125                 err = 1;
 126         }
 127
 128 out:
 129         (void) unlink(testfile);
 130         free(testfile);
 131         close(fd);
 132         return (err);
 133 }
 134
 135 static void
 136 usage(char *name)
 137 {
 138         (void) printf("%s <testfile>\n", name);
 139         exit(1);
 140 }
 141
 142 static void
 143 sigxfsz(int signo)
 144 {
 145         (void) signo;
 146         (void) printf("\nlargest_file: sigxfsz() caught SIGXFSZ\n");
 147 }