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-rw-r--r--coreutils/dd.c356
1 files changed, 356 insertions, 0 deletions
diff --git a/coreutils/dd.c b/coreutils/dd.c
new file mode 100644
index 0000000..8a40aa7
--- /dev/null
+++ b/coreutils/dd.c
@@ -0,0 +1,356 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini dd implementation for busybox
+ *
+ *
+ * Copyright (C) 2000,2001 Matt Kraai
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ */
+
+#include <signal.h> /* For FEATURE_DD_SIGNAL_HANDLING */
+#include "libbb.h"
+
+/* This is a NOEXEC applet. Be very careful! */
+
+
+enum {
+ ifd = STDIN_FILENO,
+ ofd = STDOUT_FILENO,
+};
+
+static const struct suffix_mult dd_suffixes[] = {
+ { "c", 1 },
+ { "w", 2 },
+ { "b", 512 },
+ { "kD", 1000 },
+ { "k", 1024 },
+ { "K", 1024 }, /* compat with coreutils dd */
+ { "MD", 1000000 },
+ { "M", 1048576 },
+ { "GD", 1000000000 },
+ { "G", 1073741824 },
+ { }
+};
+
+struct globals {
+ off_t out_full, out_part, in_full, in_part;
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+/* We have to zero it out because of NOEXEC */
+#define INIT_G() memset(&G, 0, sizeof(G))
+
+
+static void dd_output_status(int UNUSED_PARAM cur_signal)
+{
+ /* Deliberately using %u, not %d */
+ fprintf(stderr, "%"OFF_FMT"u+%"OFF_FMT"u records in\n"
+ "%"OFF_FMT"u+%"OFF_FMT"u records out\n",
+ G.in_full, G.in_part,
+ G.out_full, G.out_part);
+}
+
+static ssize_t full_write_or_warn(const void *buf, size_t len,
+ const char *const filename)
+{
+ ssize_t n = full_write(ofd, buf, len);
+ if (n < 0)
+ bb_perror_msg("writing '%s'", filename);
+ return n;
+}
+
+static bool write_and_stats(const void *buf, size_t len, size_t obs,
+ const char *filename)
+{
+ ssize_t n = full_write_or_warn(buf, len, filename);
+ if (n < 0)
+ return 1;
+ if ((size_t)n == obs)
+ G.out_full++;
+ else if (n) /* > 0 */
+ G.out_part++;
+ return 0;
+}
+
+#if ENABLE_LFS
+#define XATOU_SFX xatoull_sfx
+#else
+#define XATOU_SFX xatoul_sfx
+#endif
+
+int dd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int dd_main(int argc UNUSED_PARAM, char **argv)
+{
+ enum {
+ /* Must be in the same order as OP_conv_XXX! */
+ /* (see "flags |= (1 << what)" below) */
+ FLAG_NOTRUNC = 1 << 0,
+ FLAG_SYNC = 1 << 1,
+ FLAG_NOERROR = 1 << 2,
+ FLAG_FSYNC = 1 << 3,
+ /* end of conv flags */
+ FLAG_TWOBUFS = 1 << 4,
+ FLAG_COUNT = 1 << 5,
+ };
+ static const char keywords[] ALIGN1 =
+ "bs\0""count\0""seek\0""skip\0""if\0""of\0"
+#if ENABLE_FEATURE_DD_IBS_OBS
+ "ibs\0""obs\0""conv\0"
+#endif
+ ;
+#if ENABLE_FEATURE_DD_IBS_OBS
+ static const char conv_words[] ALIGN1 =
+ "notrunc\0""sync\0""noerror\0""fsync\0";
+#endif
+ enum {
+ OP_bs = 0,
+ OP_count,
+ OP_seek,
+ OP_skip,
+ OP_if,
+ OP_of,
+#if ENABLE_FEATURE_DD_IBS_OBS
+ OP_ibs,
+ OP_obs,
+ OP_conv,
+ /* Must be in the same order as FLAG_XXX! */
+ OP_conv_notrunc = 0,
+ OP_conv_sync,
+ OP_conv_noerror,
+ OP_conv_fsync,
+ /* Unimplemented conv=XXX: */
+ //nocreat do not create the output file
+ //excl fail if the output file already exists
+ //fdatasync physically write output file data before finishing
+ //swab swap every pair of input bytes
+ //lcase change upper case to lower case
+ //ucase change lower case to upper case
+ //block pad newline-terminated records with spaces to cbs-size
+ //unblock replace trailing spaces in cbs-size records with newline
+ //ascii from EBCDIC to ASCII
+ //ebcdic from ASCII to EBCDIC
+ //ibm from ASCII to alternate EBCDIC
+#endif
+ };
+ int exitcode = EXIT_FAILURE;
+ size_t ibs = 512, obs = 512;
+ ssize_t n, w;
+ char *ibuf, *obuf;
+ /* And these are all zeroed at once! */
+ struct {
+ int flags;
+ size_t oc;
+ off_t count;
+ off_t seek, skip;
+ const char *infile, *outfile;
+ } Z;
+#define flags (Z.flags )
+#define oc (Z.oc )
+#define count (Z.count )
+#define seek (Z.seek )
+#define skip (Z.skip )
+#define infile (Z.infile )
+#define outfile (Z.outfile)
+
+ memset(&Z, 0, sizeof(Z));
+ INIT_G();
+ //fflush(NULL); - is this needed because of NOEXEC?
+
+#if ENABLE_FEATURE_DD_SIGNAL_HANDLING
+ signal_SA_RESTART_empty_mask(SIGUSR1, dd_output_status);
+#endif
+
+ for (n = 1; argv[n]; n++) {
+ int what;
+ char *val;
+ char *arg = argv[n];
+
+#if ENABLE_DESKTOP
+ /* "dd --". NB: coreutils 6.9 will complain if they see
+ * more than one of them. We wouldn't. */
+ if (arg[0] == '-' && arg[1] == '-' && arg[2] == '\0')
+ continue;
+#endif
+ val = strchr(arg, '=');
+ if (val == NULL)
+ bb_show_usage();
+ *val = '\0';
+ what = index_in_strings(keywords, arg);
+ if (what < 0)
+ bb_show_usage();
+ /* *val = '='; - to preserve ps listing? */
+ val++;
+#if ENABLE_FEATURE_DD_IBS_OBS
+ if (what == OP_ibs) {
+ /* Must fit into positive ssize_t */
+ ibs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_obs) {
+ obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_conv) {
+ while (1) {
+ /* find ',', replace them with NUL so we can use val for
+ * index_in_strings() without copying.
+ * We rely on val being non-null, else strchr would fault.
+ */
+ arg = strchr(val, ',');
+ if (arg)
+ *arg = '\0';
+ what = index_in_strings(conv_words, val);
+ if (what < 0)
+ bb_error_msg_and_die(bb_msg_invalid_arg, val, "conv");
+ flags |= (1 << what);
+ if (!arg) /* no ',' left, so this was the last specifier */
+ break;
+ /* *arg = ','; - to preserve ps listing? */
+ val = arg + 1; /* skip this keyword and ',' */
+ }
+ continue; /* we trashed 'what', can't fall through */
+ }
+#endif
+ if (what == OP_bs) {
+ ibs = obs = xatoul_range_sfx(val, 1, ((size_t)-1L)/2, dd_suffixes);
+ /*continue;*/
+ }
+ /* These can be large: */
+ if (what == OP_count) {
+ flags |= FLAG_COUNT;
+ count = XATOU_SFX(val, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_seek) {
+ seek = XATOU_SFX(val, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_skip) {
+ skip = XATOU_SFX(val, dd_suffixes);
+ /*continue;*/
+ }
+ if (what == OP_if) {
+ infile = val;
+ /*continue;*/
+ }
+ if (what == OP_of) {
+ outfile = val;
+ /*continue;*/
+ }
+ } /* end of "for (argv[n])" */
+
+//XXX:FIXME for huge ibs or obs, malloc'ing them isn't the brightest idea ever
+ ibuf = obuf = xmalloc(ibs);
+ if (ibs != obs) {
+ flags |= FLAG_TWOBUFS;
+ obuf = xmalloc(obs);
+ }
+ if (infile != NULL)
+ xmove_fd(xopen(infile, O_RDONLY), ifd);
+ else {
+ infile = bb_msg_standard_input;
+ }
+ if (outfile != NULL) {
+ int oflag = O_WRONLY | O_CREAT;
+
+ if (!seek && !(flags & FLAG_NOTRUNC))
+ oflag |= O_TRUNC;
+
+ xmove_fd(xopen(outfile, oflag), ofd);
+
+ if (seek && !(flags & FLAG_NOTRUNC)) {
+ if (ftruncate(ofd, seek * obs) < 0) {
+ struct stat st;
+
+ if (fstat(ofd, &st) < 0 || S_ISREG(st.st_mode) ||
+ S_ISDIR(st.st_mode))
+ goto die_outfile;
+ }
+ }
+ } else {
+ outfile = bb_msg_standard_output;
+ }
+ if (skip) {
+ if (lseek(ifd, skip * ibs, SEEK_CUR) < 0) {
+ while (skip-- > 0) {
+ n = safe_read(ifd, ibuf, ibs);
+ if (n < 0)
+ goto die_infile;
+ if (n == 0)
+ break;
+ }
+ }
+ }
+ if (seek) {
+ if (lseek(ofd, seek * obs, SEEK_CUR) < 0)
+ goto die_outfile;
+ }
+
+ while (!(flags & FLAG_COUNT) || (G.in_full + G.in_part != count)) {
+ if (flags & FLAG_NOERROR) /* Pre-zero the buffer if conv=noerror */
+ memset(ibuf, 0, ibs);
+ n = safe_read(ifd, ibuf, ibs);
+ if (n == 0)
+ break;
+ if (n < 0) {
+ if (!(flags & FLAG_NOERROR))
+ goto die_infile;
+ n = ibs;
+ bb_simple_perror_msg(infile);
+ }
+ if ((size_t)n == ibs)
+ G.in_full++;
+ else {
+ G.in_part++;
+ if (flags & FLAG_SYNC) {
+ memset(ibuf + n, '\0', ibs - n);
+ n = ibs;
+ }
+ }
+ if (flags & FLAG_TWOBUFS) {
+ char *tmp = ibuf;
+ while (n) {
+ size_t d = obs - oc;
+
+ if (d > (size_t)n)
+ d = n;
+ memcpy(obuf + oc, tmp, d);
+ n -= d;
+ tmp += d;
+ oc += d;
+ if (oc == obs) {
+ if (write_and_stats(obuf, obs, obs, outfile))
+ goto out_status;
+ oc = 0;
+ }
+ }
+ } else if (write_and_stats(ibuf, n, obs, outfile))
+ goto out_status;
+
+ if (flags & FLAG_FSYNC) {
+ if (fsync(ofd) < 0)
+ goto die_outfile;
+ }
+ }
+
+ if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
+ w = full_write_or_warn(obuf, oc, outfile);
+ if (w < 0) goto out_status;
+ if (w > 0) G.out_part++;
+ }
+ if (close(ifd) < 0) {
+ die_infile:
+ bb_simple_perror_msg_and_die(infile);
+ }
+
+ if (close(ofd) < 0) {
+ die_outfile:
+ bb_simple_perror_msg_and_die(outfile);
+ }
+
+ exitcode = EXIT_SUCCESS;
+ out_status:
+ dd_output_status(0);
+
+ return exitcode;
+}