2 * This file is part of vbig.
3 * Copyright (C) 2011 Richard Kettlewell
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
29 // Command line options
30 const struct option opts[] = {
31 { "seed", required_argument, 0, 's' },
32 { "verify", no_argument, 0, 'v' },
33 { "create", no_argument, 0, 'c' },
34 { "flush", no_argument, 0, 'f' },
35 { "help", no_argument, 0, 'h' },
36 { "version", no_argument, 0, 'V' },
40 // Display help message
41 static void help(void) {
42 printf("vbig - create or verify a large but pseudo-random file\n"
45 " vbig [--seed SEED] --verify|--create PATH SIZE\n"
48 " --seed, -s Specify random seed\n"
49 " --verify, -v Verify that PATH contains the expected contents\n"
50 " --create, -c Create PATH with psuedo-random contents\n"
51 " --flush, -f Flush cache\n"
52 " --help, -h Display usage message\n"
53 " --version, -V Display version string\n");
56 // Possible modes of operation
63 // Report an error and exit
64 static void fatal(int errno_value, const char *fmt, ...) {
66 fprintf(stderr, "ERROR: ");
68 vfprintf(stderr, fmt, ap);
71 fprintf(stderr, ": %s", strerror(errno_value));
76 // Evict whatever FP points to from RAM
77 static void flushCache(FILE *fp) {
78 // drop_caches only evicts clean pages, so first the target file is
80 if(fsync(fileno(fp)) < 0)
81 fatal(errno, "fsync");
82 #if defined DROP_CACHE_FILE
84 if((fd = open(DROP_CACHE_FILE, O_WRONLY, 0)) < 0)
85 fatal(errno, "%s", DROP_CACHE_FILE);
86 if(write(fd, "3\n", 2) < 0)
87 fatal(errno, "%s", DROP_CACHE_FILE);
89 #elif defined PURGE_COMMAND
91 if((rc = system(PURGE_COMMAND)) < 0)
92 fatal(errno, "executing %s", PURGE_COMMAND);
95 fprintf(stderr, "%s%s\n",
96 strsignal(WTERMSIG(rc)),
97 WCOREDUMP(rc) ? " (core dumped)" : "");
98 exit(WTERMSIG(rc) + 128);
100 exit(WEXITSTATUS(rc));
105 int main(int argc, char **argv) {
106 const char *seed = "hexapodia as the key insight";
107 mode_type mode = NONE;
110 while((n = getopt_long(argc, argv, "+s:vcfhV", opts, 0)) >= 0) {
112 case 's': seed = optarg; break;
113 case 'v': mode = VERIFY; break;
114 case 'c': mode = CREATE; break;
115 case 'f': flush = true; break;
116 case 'h': help(); exit(0);
117 case 'V': puts(VERSION); exit(0);
119 fatal(0, "unknown option");
123 fatal(0, "must specify one of --verify or --create");
126 if(optind + 2 != argc) {
127 fatal(0, "must specify a path and size");
130 const char *path = argv[optind];
133 long long size = strtoll(argv[optind + 1], &end, 10);
135 fatal(errno, "invalid size");
138 if(end == argv[optind + 1]) {
139 fatal(0, "invalid size");
142 if(!strcmp(end, "K"))
144 else if(!strcmp(end, "M"))
146 else if(!strcmp(end, "G"))
147 size *= 1024 * 1024 * 1024;
149 fatal(0, "invalid size");
152 Arcfour rng(seed, strlen(seed));
153 FILE *fp = fopen(path, mode == VERIFY ? "rb" : "wb");
155 fatal(errno, "%s", path);
158 if(mode == VERIFY && flush)
160 char generated[4096], input[4096];
161 long long remain = size;
163 size_t bytesGenerated = (remain > (ssize_t)sizeof generated
166 rng.stream(generated, bytesGenerated);
168 fwrite(generated, 1, bytesGenerated, fp);
170 fatal(errno, "%s", path);
174 size_t bytesRead = fread(input, 1, bytesGenerated, fp);
176 fatal(errno, "%s", path);
179 if(bytesRead < bytesGenerated) {
180 fatal(0, "%s: truncated at %lld/%lld bytes",
181 path, (size - remain + bytesRead), size);
184 if(memcmp(generated, input, bytesGenerated)) {
185 for(size_t n = 0; n < bytesGenerated; ++n)
186 if(generated[n] != input[n]){
187 fatal(0, "%s corrupted at %lld/%lld bytes (expected %d got %d)",
188 path, size - remain + n, size,
189 (unsigned char)generated[n], (unsigned char)input[n]);
194 remain -= bytesGenerated;
196 if(mode == VERIFY && getc(fp) != EOF) {
197 fatal(0, "%s: extended beyond %lld bytes",
201 if(mode == CREATE && flush) {
203 fatal(errno, "%s", path);
207 fatal(errno, "%s", path);