1 /* vi: set sw=4 ts=4: */
3 * Mini dd implementation for busybox
6 * Copyright (C) 2000,2001 Matt Kraai
8 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
13 /* This is a NOEXEC applet. Be very careful! */
21 static const struct suffix_mult dd_suffixes[] = {
27 { "K", 1024 }, /* compat with coreutils dd */
36 off_t out_full, out_part, in_full, in_part;
37 #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
38 unsigned long long total_bytes;
39 unsigned long long begin_time_us;
42 #define G (*(struct globals*)&bb_common_bufsiz1)
43 #define INIT_G() do { \
44 /* we have to zero it out because of NOEXEC */ \
45 memset(&G, 0, sizeof(G)); \
49 static void dd_output_status(int UNUSED_PARAM cur_signal)
51 #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
53 unsigned long long bytes_sec;
54 unsigned long long now_us = monotonic_us(); /* before fprintf */
57 /* Deliberately using %u, not %d */
58 fprintf(stderr, "%"OFF_FMT"u+%"OFF_FMT"u records in\n"
59 "%"OFF_FMT"u+%"OFF_FMT"u records out\n",
61 G.out_full, G.out_part);
63 #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
64 fprintf(stderr, "%llu bytes (%sB) copied, ",
66 /* show fractional digit, use suffixes */
67 make_human_readable_str(G.total_bytes, 1, 0)
70 * ./busybox dd </dev/null >/dev/null
71 * ./busybox dd bs=1M count=2000 </dev/zero >/dev/null
72 * (echo DONE) | ./busybox dd >/dev/null
73 * (sleep 1; echo DONE) | ./busybox dd >/dev/null
75 seconds = (now_us - G.begin_time_us) / 1000000.0;
76 bytes_sec = G.total_bytes / seconds;
77 fprintf(stderr, "%f seconds, %sB/s\n",
79 /* show fractional digit, use suffixes */
80 make_human_readable_str(bytes_sec, 1, 0)
85 static ssize_t full_write_or_warn(const void *buf, size_t len,
86 const char *const filename)
88 ssize_t n = full_write(ofd, buf, len);
90 bb_perror_msg("writing '%s'", filename);
94 static bool write_and_stats(const void *buf, size_t len, size_t obs,
97 ssize_t n = full_write_or_warn(buf, len, filename);
100 if ((size_t)n == obs)
102 else if (n) /* > 0 */
104 #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
111 # define XATOU_SFX xatoull_sfx
113 # define XATOU_SFX xatoul_sfx
116 int dd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
117 int dd_main(int argc UNUSED_PARAM, char **argv)
120 /* Must be in the same order as OP_conv_XXX! */
121 /* (see "flags |= (1 << what)" below) */
122 FLAG_NOTRUNC = 1 << 0,
124 FLAG_NOERROR = 1 << 2,
126 /* end of conv flags */
127 FLAG_TWOBUFS = 1 << 4,
130 static const char keywords[] ALIGN1 =
131 "bs\0""count\0""seek\0""skip\0""if\0""of\0"
132 #if ENABLE_FEATURE_DD_IBS_OBS
133 "ibs\0""obs\0""conv\0"
136 #if ENABLE_FEATURE_DD_IBS_OBS
137 static const char conv_words[] ALIGN1 =
138 "notrunc\0""sync\0""noerror\0""fsync\0";
147 #if ENABLE_FEATURE_DD_IBS_OBS
151 /* Must be in the same order as FLAG_XXX! */
156 /* Unimplemented conv=XXX: */
157 //nocreat do not create the output file
158 //excl fail if the output file already exists
159 //fdatasync physically write output file data before finishing
160 //swab swap every pair of input bytes
161 //lcase change upper case to lower case
162 //ucase change lower case to upper case
163 //block pad newline-terminated records with spaces to cbs-size
164 //unblock replace trailing spaces in cbs-size records with newline
165 //ascii from EBCDIC to ASCII
166 //ebcdic from ASCII to EBCDIC
167 //ibm from ASCII to alternate EBCDIC
170 int exitcode = EXIT_FAILURE;
171 size_t ibs = 512, obs = 512;
174 /* And these are all zeroed at once! */
180 const char *infile, *outfile;
182 #define flags (Z.flags )
184 #define count (Z.count )
185 #define seek (Z.seek )
186 #define skip (Z.skip )
187 #define infile (Z.infile )
188 #define outfile (Z.outfile)
190 memset(&Z, 0, sizeof(Z));
192 //fflush_all(); - is this needed because of NOEXEC?
194 for (n = 1; argv[n]; n++) {
200 /* "dd --". NB: coreutils 6.9 will complain if they see
201 * more than one of them. We wouldn't. */
202 if (arg[0] == '-' && arg[1] == '-' && arg[2] == '\0')
205 val = strchr(arg, '=');
209 what = index_in_strings(keywords, arg);
212 /* *val = '='; - to preserve ps listing? */
214 #if ENABLE_FEATURE_DD_IBS_OBS
215 if (what == OP_ibs) {
216 /* Must fit into positive ssize_t */
217 ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
220 if (what == OP_obs) {
221 obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
224 if (what == OP_conv) {
226 /* find ',', replace them with NUL so we can use val for
227 * index_in_strings() without copying.
228 * We rely on val being non-null, else strchr would fault.
230 arg = strchr(val, ',');
233 what = index_in_strings(conv_words, val);
235 bb_error_msg_and_die(bb_msg_invalid_arg, val, "conv");
236 flags |= (1 << what);
237 if (!arg) /* no ',' left, so this was the last specifier */
239 /* *arg = ','; - to preserve ps listing? */
240 val = arg + 1; /* skip this keyword and ',' */
242 continue; /* we trashed 'what', can't fall through */
246 ibs = obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
249 /* These can be large: */
250 if (what == OP_count) {
252 count = XATOU_SFX(val, dd_suffixes);
255 if (what == OP_seek) {
256 seek = XATOU_SFX(val, dd_suffixes);
259 if (what == OP_skip) {
260 skip = XATOU_SFX(val, dd_suffixes);
271 } /* end of "for (argv[n])" */
273 //XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
274 ibuf = obuf = xmalloc(ibs);
276 flags |= FLAG_TWOBUFS;
280 #if ENABLE_FEATURE_DD_SIGNAL_HANDLING
281 signal_SA_RESTART_empty_mask(SIGUSR1, dd_output_status);
283 #if ENABLE_FEATURE_DD_THIRD_STATUS_LINE
284 G.begin_time_us = monotonic_us();
288 xmove_fd(xopen(infile, O_RDONLY), ifd);
290 infile = bb_msg_standard_input;
292 if (outfile != NULL) {
293 int oflag = O_WRONLY | O_CREAT;
295 if (!seek && !(flags & FLAG_NOTRUNC))
298 xmove_fd(xopen(outfile, oflag), ofd);
300 if (seek && !(flags & FLAG_NOTRUNC)) {
301 if (ftruncate(ofd, seek * obs) < 0) {
304 if (fstat(ofd, &st) < 0 || S_ISREG(st.st_mode) ||
310 outfile = bb_msg_standard_output;
313 if (lseek(ifd, skip * ibs, SEEK_CUR) < 0) {
315 n = safe_read(ifd, ibuf, ibs);
324 if (lseek(ofd, seek * obs, SEEK_CUR) < 0)
328 while (!(flags & FLAG_COUNT) || (G.in_full + G.in_part != count)) {
329 n = safe_read(ifd, ibuf, ibs);
334 if (!(flags & FLAG_NOERROR))
336 bb_simple_perror_msg(infile);
337 /* GNU dd with conv=noerror skips over bad blocks */
338 xlseek(ifd, ibs, SEEK_CUR);
339 /* conv=noerror,sync writes NULs,
340 * conv=noerror just ignores input bad blocks */
343 if ((size_t)n == ibs)
347 if (flags & FLAG_SYNC) {
348 memset(ibuf + n, 0, ibs - n);
352 if (flags & FLAG_TWOBUFS) {
359 memcpy(obuf + oc, tmp, d);
364 if (write_and_stats(obuf, obs, obs, outfile))
369 } else if (write_and_stats(ibuf, n, obs, outfile))
372 if (flags & FLAG_FSYNC) {
378 if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
379 w = full_write_or_warn(obuf, oc, outfile);
380 if (w < 0) goto out_status;
381 if (w > 0) G.out_part++;
383 if (close(ifd) < 0) {
385 bb_simple_perror_msg_and_die(infile);
388 if (close(ofd) < 0) {
390 bb_simple_perror_msg_and_die(outfile);
393 exitcode = EXIT_SUCCESS;