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/>.
32 // Command line options
33 const struct option opts[] = {
34 { "seed", required_argument, 0, 's' },
35 { "verify", no_argument, 0, 'v' },
36 { "create", no_argument, 0, 'c' },
37 { "flush", no_argument, 0, 'f' },
38 { "entire", no_argument, 0, 'e' },
39 { "help", no_argument, 0, 'h' },
40 { "version", no_argument, 0, 'V' },
44 // Display help message
45 static void help(void) {
46 printf("vbig - create or verify a large but pseudo-random file\n"
49 " vbig [--seed SEED] --verify|--create PATH [SIZE]\n"
52 " --seed, -s Specify random seed\n"
53 " --verify, -v Verify that PATH contains the expected contents\n"
54 " --create, -c Create PATH with psuedo-random contents\n"
55 " --flush, -f Flush cache\n"
56 " --entire, -e Write until full; read until EOF\n"
57 " --help, -h Display usage message\n"
58 " --version, -V Display version string\n");
61 // Possible modes of operation
68 // Report an error and exit
69 static void fatal(int errno_value, const char *fmt, ...) {
71 fprintf(stderr, "ERROR: ");
73 vfprintf(stderr, fmt, ap);
76 fprintf(stderr, ": %s", strerror(errno_value));
81 // Evict whatever FP points to from RAM
82 static void flushCache(FILE *fp) {
83 // drop_caches only evicts clean pages, so first the target file is
85 if(fsync(fileno(fp)) < 0)
86 fatal(errno, "fsync");
87 #if defined DROP_CACHE_FILE
89 if((fd = open(DROP_CACHE_FILE, O_WRONLY, 0)) < 0)
90 fatal(errno, "%s", DROP_CACHE_FILE);
91 if(write(fd, "3\n", 2) < 0)
92 fatal(errno, "%s", DROP_CACHE_FILE);
94 #elif defined PURGE_COMMAND
96 if((rc = system(PURGE_COMMAND)) < 0)
97 fatal(errno, "executing %s", PURGE_COMMAND);
100 fprintf(stderr, "%s%s\n",
101 strsignal(WTERMSIG(rc)),
102 WCOREDUMP(rc) ? " (core dumped)" : "");
103 exit(WTERMSIG(rc) + 128);
105 exit(WEXITSTATUS(rc));
110 static void execute(mode_type mode, bool entire, const char *show);
112 static const char *seed = "hexapodia as the key insight";
113 static const char *path;
114 static bool entireopt = false;
115 static bool flush = false;
116 static long long size;
118 int main(int argc, char **argv) {
119 mode_type mode = NONE;
121 while((n = getopt_long(argc, argv, "+s:vcefhV", opts, 0)) >= 0) {
123 case 's': seed = optarg; break;
124 case 'v': mode = VERIFY; break;
125 case 'c': mode = CREATE; break;
126 case 'e': entireopt = true; break;
127 case 'f': flush = true; break;
128 case 'h': help(); exit(0);
129 case 'V': puts(VERSION); exit(0);
131 fatal(0, "unknown option");
137 fatal(0, "must specify one of --verify or --create");
139 fatal(0, "excess arguments");
142 fatal(0, "with --entire, size should not be specified");
144 if(argc < (mode == VERIFY ? 1 : 2))
145 fatal(0, "insufficient arguments");
151 size = strtoll(argv[1], &end, 10);
153 fatal(errno, "invalid size");
155 fatal(0, "invalid size");
156 if(!strcmp(end, "K"))
158 else if(!strcmp(end, "M"))
160 else if(!strcmp(end, "G"))
161 size *= 1024 * 1024 * 1024;
163 fatal(0, "invalid size");
164 } else if(entireopt) {
165 size = LONG_LONG_MAX;
168 if(stat(path, &sb) < 0)
169 fatal(errno, "stat %s", path);
172 const char *show = entireopt ? (mode == CREATE ? "written" : "verified") : 0;
173 execute(mode, entireopt, show);
177 static void execute(mode_type mode, bool entire, const char *show) {
178 Arcfour rng(seed, strlen(seed));
179 FILE *fp = fopen(path, mode == VERIFY ? "rb" : "wb");
181 fatal(errno, "%s", path);
182 if(mode == VERIFY && flush)
184 if(mode == CREATE && entire)
185 setvbuf(fp, 0, _IONBF, 0);
186 char generated[4096], input[4096];
187 long long remain = size;
189 size_t bytesGenerated = (remain > (ssize_t)sizeof generated
192 rng.stream(generated, bytesGenerated);
194 size_t bytesWritten = fwrite(generated, 1, bytesGenerated, fp);
196 if(!entire || errno != ENOSPC)
197 fatal(errno, "%s", path);
198 remain -= bytesWritten;
201 assert(bytesWritten == bytesGenerated);
203 size_t bytesRead = fread(input, 1, bytesGenerated, fp);
205 fatal(errno, "%s", path);
206 if(memcmp(generated, input, bytesRead)) {
207 for(size_t n = 0; n < bytesRead; ++n)
208 if(generated[n] != input[n])
209 fatal(0, "%s corrupted at %lld/%lld bytes (expected %d got %d)",
210 path, size - remain + n, size,
211 (unsigned char)generated[n], (unsigned char)input[n]);
213 if(bytesRead < bytesGenerated) {
219 fatal(0, "%s: truncated at %lld/%lld bytes",
220 path, (size - remain + bytesRead), size);
223 remain -= bytesGenerated;
225 if(mode == VERIFY && !entire && getc(fp) != EOF)
226 fatal(0, "%s: extended beyond %lld bytes",
228 if(mode == CREATE && flush) {
230 fatal(errno, "%s", path);
234 fatal(errno, "%s", path);
235 long long done = size - remain;
237 printf("%lld bytes (%lldM, %lldG) %s\n",
238 done, done >> 20, done >> 30,
240 if(ferror(stdout) || fflush(stdout))
241 fatal(errno, "flush stdout");