1 /* dd.c - program to convert and copy a file. 2 * 3 * Copyright 2013 Ashwini Kumar <ak.ashwini (at) gmail.com> 4 * Copyright 2013 Kyungwan Han <asura321 (at) gmail.com> 5 * 6 * See http://opengroup.org/onlinepubs/9699919799/utilities/dd.html 7 USE_DD(NEWTOY(dd, NULL, TOYFLAG_USR|TOYFLAG_BIN)) 8 9 config DD 10 bool "dd" 11 default n 12 help 13 usage: dd [if=FILE] [of=FILE] [ibs=N] [obs=N] [bs=N] [count=N] [skip=N] 14 [seek=N] [conv=notrunc|noerror|sync|fsync] 15 16 Options: 17 if=FILE Read from FILE instead of stdin 18 of=FILE Write to FILE instead of stdout 19 bs=N Read and write N bytes at a time 20 ibs=N Read N bytes at a time 21 obs=N Write N bytes at a time 22 count=N Copy only N input blocks 23 skip=N Skip N input blocks 24 seek=N Skip N output blocks 25 conv=notrunc Don't truncate output file 26 conv=noerror Continue after read errors 27 conv=sync Pad blocks with zeros 28 conv=fsync Physically write data out before finishing 29 30 Numbers may be suffixed by c (x1), w (x2), b (x512), kD (x1000), k (x1024), 31 MD (x1000000), M (x1048576), GD (x1000000000) or G (x1073741824) 32 Copy a file, converting and formatting according to the operands. 33 */ 34 #define FOR_dd 35 #include "toys.h" 36 37 GLOBALS( 38 int sig; 39 ) 40 #define C_CONV 0x0000 41 #define C_BS 0x0001 42 #define C_COUNT 0x0002 43 #define C_IBS 0x0004 44 #define C_OBS 0x0008 45 #define C_IF 0x0010 46 #define C_OF 0x0020 47 #define C_SEEK 0x0040 48 #define C_SKIP 0x0080 49 #define C_SYNC 0x0100 50 #define C_FSYNC 0x0200 51 #define C_NOERROR 0x0400 52 #define C_NOTRUNC 0x0800 53 54 struct io { 55 char *name; 56 int fd; 57 unsigned char *buff, *bp; 58 long sz, count; 59 unsigned long long offset; 60 }; 61 62 struct iostat { 63 unsigned long long in_full, in_part, out_full, out_part, bytes; 64 struct timeval start; 65 }; 66 67 struct pair { 68 char *name; 69 unsigned val; 70 }; 71 72 static struct pair suffixes[] = { 73 { "c", 1 }, { "w", 2 }, { "b", 512 }, 74 { "kD", 1000 }, { "k", 1024 }, { "K", 1024 }, 75 { "MD", 1000000 }, { "M", 1048576 }, 76 { "GD", 1000000000 }, { "G", 1073741824 } 77 }; 78 79 static struct pair clist[] = { 80 { "fsync", C_FSYNC }, 81 { "noerror", C_NOERROR }, 82 { "notrunc", C_NOTRUNC }, 83 { "sync", C_SYNC }, 84 }; 85 86 static struct pair operands[] = { 87 // keep the array sorted by name, bsearch() can be used. 88 { "bs", C_BS }, 89 { "conv", C_CONV }, 90 { "count", C_COUNT}, 91 { "ibs", C_IBS }, 92 { "if", C_IF }, 93 { "obs", C_OBS }, 94 { "of", C_OF }, 95 { "seek", C_SEEK }, 96 { "skip", C_SKIP }, 97 }; 98 99 static struct io in, out; 100 static struct iostat st; 101 static unsigned long long c_count; 102 103 static unsigned long long strsuftoll(char* arg, int def, unsigned long long max) 104 { 105 unsigned long long result; 106 char *endp, *ch = arg; 107 int i, idx = -1; 108 errno = 0; 109 110 while (isspace(*ch)) ch++; 111 if (*ch == '-') error_exit("invalid number '%s'",arg); 112 result = strtoull(arg, &endp, 10); 113 if (errno == ERANGE || result > max || result < def) 114 perror_exit("invalid number '%s'",arg); 115 if (*endp != '\0') { 116 for (i = 0; i < ARRAY_LEN(suffixes); i++) 117 if (!strcmp(endp, suffixes[i].name)) idx = i; 118 if (idx == -1 || (max/suffixes[idx].val < result)) 119 error_exit("invalid number '%s'",arg); 120 result = result* suffixes[idx].val; 121 } 122 return result; 123 } 124 125 static void summary() 126 { 127 double seconds = 5.0; 128 struct timeval now; 129 130 gettimeofday(&now, NULL); 131 seconds = ((now.tv_sec * 1000000 + now.tv_usec) - (st.start.tv_sec * 1000000 132 + st.start.tv_usec))/1000000.0; 133 //out to STDERR 134 fprintf(stderr,"%llu+%llu records in\n%llu+%llu records out\n", st.in_full, st.in_part, 135 st.out_full, st.out_part); 136 human_readable(toybuf, st.bytes, HR_SPACE|HR_B); 137 fprintf(stderr, "%llu bytes (%s) copied, ",st.bytes, toybuf); 138 human_readable(toybuf, st.bytes/seconds, HR_SPACE|HR_B); 139 fprintf(stderr, "%f s, %s/s\n", seconds, toybuf); 140 } 141 142 static void sig_handler(int sig) 143 { 144 TT.sig = sig; 145 } 146 147 static int xmove_fd(int fd) 148 { 149 int newfd; 150 151 if (fd > STDERR_FILENO) return fd; 152 if ((newfd = fcntl(fd, F_DUPFD, 3) < 0)) perror_exit("dupfd IO"); 153 close(fd); 154 return newfd; 155 } 156 157 static void setup_inout() 158 { 159 ssize_t n; 160 161 /* for C_BS, in/out is done as it is. so only in.sz is enough. 162 * With Single buffer there will be overflow in a read following partial read 163 */ 164 in.buff = out.buff = xmalloc(in.sz + ((toys.optflags & C_BS)? 0: out.sz)); 165 in.bp = out.bp = in.buff; 166 atexit(summary); 167 //setup input 168 if (!in.name) { 169 in.name = "stdin"; 170 in.fd = STDIN_FILENO; 171 } else { 172 in.fd = xopen(in.name, O_RDONLY); 173 in.fd = xmove_fd(in.fd); 174 } 175 //setup outout 176 if (!out.name) { 177 out.name = "stdout"; 178 out.fd = STDOUT_FILENO; 179 } else { 180 out.fd = xcreate(out.name, O_WRONLY | O_CREAT, 0666); 181 out.fd = xmove_fd(out.fd); 182 } 183 184 if (in.offset) { 185 if (lseek(in.fd, (off_t)(in.offset * in.sz), SEEK_CUR) < 0) { 186 while (in.offset--) { 187 if ((n = read(in.fd, in.bp, in.sz)) < 0) { 188 if (toys.optflags & C_NOERROR) { //warn message and summary 189 error_msg("%s: read error", in.name); 190 summary(); 191 } else perror_exit("%s: read error", in.name); 192 } else if (!n) { 193 xprintf("%s: Can't skip\n", in.name); 194 exit(0); 195 } 196 } 197 } 198 } 199 200 if (out.offset) xlseek(out.fd, (off_t)(out.offset * out.sz), SEEK_CUR); 201 } 202 203 static void write_out(int all) 204 { 205 ssize_t nw; 206 out.bp = out.buff; 207 while (out.count) { 208 nw = writeall(out.fd, out.bp, ((all)? out.count : out.sz)); 209 all = 0; //further writes will be on obs 210 if (nw <= 0) perror_exit("%s: write error",out.name); 211 if (nw == out.sz) st.out_full++; 212 else st.out_part++; 213 out.count -= nw; 214 out.bp += nw; 215 st.bytes += nw; 216 if (out.count < out.sz) break; 217 } 218 if (out.count) memmove(out.buff, out.bp, out.count); //move remainder to front 219 } 220 221 static void do_dd(void) 222 { 223 ssize_t n; 224 struct sigaction sa; 225 226 memset(&sa, 0, sizeof(sa)); 227 sa.sa_handler = sig_handler; 228 sigaction(SIGINT, &sa, NULL); 229 sigaction(SIGUSR1, &sa, NULL); 230 setup_inout(); 231 gettimeofday(&st.start, NULL); 232 233 if (toys.optflags & (C_OF | C_SEEK) && !(toys.optflags & C_NOTRUNC)) 234 ftruncate(out.fd, (off_t)out.offset * out.sz); 235 236 while (!(toys.optflags & C_COUNT) || (st.in_full + st.in_part) < c_count) { 237 if (TT.sig == SIGUSR1) { 238 summary(); 239 TT.sig = 0; 240 } else if (TT.sig == SIGINT) exit(TT.sig | 128); 241 in.bp = in.buff + in.count; 242 if (toys.optflags & C_SYNC) memset(in.bp, 0, in.sz); 243 if (!(n = read(in.fd, in.bp, in.sz))) break; 244 if (n < 0) { 245 if (errno == EINTR) continue; 246 //read error case. 247 perror_msg("%s: read error", in.name); 248 if (!(toys.optflags & C_NOERROR)) exit(1); 249 summary(); 250 xlseek(in.fd, in.sz, SEEK_CUR); 251 if (!(toys.optflags & C_SYNC)) continue; 252 // if SYNC, then treat as full block of nuls 253 n = in.sz; 254 } 255 if (n == in.sz) { 256 st.in_full++; 257 in.count += n; 258 } else { 259 st.in_part++; 260 if (toys.optflags & C_SYNC) in.count += in.sz; 261 else in.count += n; 262 } 263 264 out.count = in.count; 265 if (toys.optflags & C_BS) { 266 write_out(1); 267 in.count = 0; 268 continue; 269 } 270 271 if (in.count >= out.sz) { 272 write_out(0); 273 in.count = out.count; 274 } 275 } 276 if (out.count) write_out(1); //write any remaining input blocks 277 if (toys.optflags & C_FSYNC && fsync(out.fd) < 0) 278 perror_exit("%s: fsync fail", out.name); 279 280 close(in.fd); 281 close(out.fd); 282 if (in.buff) free(in.buff); 283 } 284 285 static int comp(const void *a, const void *b) //const to shut compiler up 286 { 287 return strcmp(((struct pair*)a)->name, ((struct pair*)b)->name); 288 } 289 290 void dd_main() 291 { 292 struct pair *res, key; 293 char *arg; 294 long sz; 295 296 in.sz = out.sz = 512; //default io block size 297 while (*toys.optargs) { 298 if (!(arg = strchr(*toys.optargs, '='))) error_exit("unknown arg %s", *toys.optargs); 299 *arg++ = '\0'; 300 if (!*arg) help_exit(0); 301 key.name = *toys.optargs; 302 if (!(res = bsearch(&key, operands, ARRAY_LEN(operands), sizeof(struct pair), 303 comp))) error_exit("unknown arg %s", key.name); 304 305 toys.optflags |= res->val; 306 switch(res->val) { 307 case C_BS: 308 in.sz = out.sz = strsuftoll(arg, 1, LONG_MAX); 309 break; 310 case C_IBS: 311 sz = strsuftoll(arg, 1, LONG_MAX); 312 if (!(toys.optflags & C_BS)) in.sz = sz; 313 break; 314 case C_OBS: 315 sz = strsuftoll(arg, 1, LONG_MAX); 316 if (!(toys.optflags & C_BS)) out.sz = sz; 317 break; 318 case C_COUNT: 319 c_count = strsuftoll(arg, 0, ULLONG_MAX); 320 break; 321 case C_IF: 322 in.name = arg; 323 break; 324 case C_OF: 325 out.name = arg; 326 break; 327 case C_SEEK: 328 out.offset = strsuftoll(arg, 0, ULLONG_MAX); 329 break; 330 case C_SKIP: 331 in.offset = strsuftoll(arg, 0, ULLONG_MAX); 332 break; 333 case C_CONV: 334 while (arg) { 335 key.name = strsep(&arg, ","); 336 if (!(res = bsearch(&key, clist, ARRAY_LEN(clist), 337 sizeof(struct pair), comp))) 338 error_exit("unknown conversion %s", key.name); 339 340 toys.optflags |= res->val; 341 } 342 break; 343 } 344 toys.optargs++; 345 } 346 347 do_dd(); 348 } 349
