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Diffstat (limited to 'coreutils/dd.c')
-rw-r--r--coreutils/dd.c139
1 files changed, 83 insertions, 56 deletions
diff --git a/coreutils/dd.c b/coreutils/dd.c
index 378e212..53aa085 100644
--- a/coreutils/dd.c
+++ b/coreutils/dd.c
@@ -45,21 +45,13 @@ static void dd_output_status(int cur_signal)
int dd_main(int argc, char **argv)
{
- size_t count = -1;
- size_t bs = 512;
+ size_t count = -1, oc = 0, ibs = 512, obs = 512;
ssize_t n;
- off_t seek = 0;
- off_t skip = 0;
- int sync_flag = FALSE;
- int noerror = FALSE;
- int trunc_flag = TRUE;
- int oflag;
- int ifd;
- int ofd;
- int i;
- const char *infile = NULL;
- const char *outfile = NULL;
- char *buf;
+ off_t seek = 0, skip = 0;
+ int sync_flag = FALSE, noerror = FALSE, trunc_flag = TRUE, twobufs_flag = 0,
+ oflag, ifd, ofd, i;
+ const char *infile = NULL, *outfile = NULL;
+ char *ibuf, *obuf;
if (ENABLE_FEATURE_DD_SIGNAL_HANDLING)
{
@@ -73,43 +65,49 @@ int dd_main(int argc, char **argv)
}
for (i = 1; i < argc; i++) {
- if (strncmp("bs=", argv[i], 3) == 0)
- bs = bb_xparse_number(argv[i]+3, dd_suffixes);
- else if (strncmp("count=", argv[i], 6) == 0)
+ if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("ibs=", argv[i], 4)) {
+ ibs = bb_xparse_number(argv[i]+4, dd_suffixes);
+ twobufs_flag++;
+ } else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("obs=", argv[i], 4)) {
+ obs = bb_xparse_number(argv[i]+4, dd_suffixes);
+ twobufs_flag++;
+ } else if (!strncmp("bs=", argv[i], 3)) {
+ ibs = obs = bb_xparse_number(argv[i]+3, dd_suffixes);
+ } else if (!strncmp("count=", argv[i], 6))
count = bb_xparse_number(argv[i]+6, dd_suffixes);
- else if (strncmp("seek=", argv[i], 5) == 0)
+ else if (!strncmp("seek=", argv[i], 5))
seek = bb_xparse_number(argv[i]+5, dd_suffixes);
- else if (strncmp("skip=", argv[i], 5) == 0)
+ else if (!strncmp("skip=", argv[i], 5))
skip = bb_xparse_number(argv[i]+5, dd_suffixes);
- else if (strncmp("if=", argv[i], 3) == 0)
+ else if (!strncmp("if=", argv[i], 3))
infile = argv[i]+3;
- else if (strncmp("of=", argv[i], 3) == 0)
+ else if (!strncmp("of=", argv[i], 3))
outfile = argv[i]+3;
- else if (strncmp("conv=", argv[i], 5) == 0) {
- buf = argv[i]+5;
+ else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("conv=", argv[i], 5)) {
+ ibuf = argv[i]+5;
while (1) {
- if (strncmp("notrunc", buf, 7) == 0) {
+ if (!strncmp("notrunc", ibuf, 7)) {
trunc_flag = FALSE;
- buf += 7;
- } else if (strncmp("sync", buf, 4) == 0) {
+ ibuf += 7;
+ } else if (!strncmp("sync", ibuf, 4)) {
sync_flag = TRUE;
- buf += 4;
- } else if (strncmp("noerror", buf, 7) == 0) {
+ ibuf += 4;
+ } else if (!strncmp("noerror", ibuf, 7)) {
noerror = TRUE;
- buf += 7;
+ ibuf += 7;
} else {
bb_error_msg_and_die("invalid conversion `%s'", argv[i]+5);
}
- if (buf[0] == '\0')
- break;
- if (buf[0] == ',')
- buf++;
+ if (ibuf[0] == '\0') break;
+ if (ibuf[0] == ',') ibuf++;
}
} else
bb_show_usage();
}
+ ibuf = xmalloc(ibs);
- buf = xmalloc(bs);
+ if (twobufs_flag) obuf = xmalloc(obs);
+ else obuf = ibuf;
if (infile != NULL) {
ifd = bb_xopen(infile, O_RDONLY);
@@ -128,7 +126,7 @@ int dd_main(int argc, char **argv)
ofd = bb_xopen3(outfile, oflag, 0666);
if (seek && trunc_flag) {
- if (ftruncate(ofd, seek * bs) < 0) {
+ if (ftruncate(ofd, seek * obs) < 0) {
struct stat st;
if (fstat (ofd, &st) < 0 || S_ISREG (st.st_mode) ||
@@ -143,13 +141,19 @@ int dd_main(int argc, char **argv)
}
if (skip) {
- if (lseek(ifd, skip * bs, SEEK_CUR) < 0) {
- bb_perror_msg_and_die("%s", infile);
+ if (lseek(ifd, skip * ibs, SEEK_CUR) < 0) {
+ while (skip-- > 0) {
+ n = safe_read(ifd, ibuf, ibs);
+ if (n < 0)
+ bb_perror_msg_and_die("%s", infile);
+ if (n == 0)
+ break;
+ }
}
}
if (seek) {
- if (lseek(ofd, seek * bs, SEEK_CUR) < 0) {
+ if (lseek(ofd, seek * obs, SEEK_CUR) < 0) {
bb_perror_msg_and_die("%s", outfile);
}
}
@@ -157,40 +161,63 @@ int dd_main(int argc, char **argv)
while (in_full + in_part != count) {
if (noerror) {
/* Pre-zero the buffer when doing the noerror thing */
- memset(buf, '\0', bs);
+ memset(ibuf, '\0', ibs);
+ }
+
+ n = safe_read(ifd, ibuf, ibs);
+ if (n == 0) {
+ break;
}
- n = safe_read(ifd, buf, bs);
if (n < 0) {
if (noerror) {
- n = bs;
+ n = ibs;
bb_perror_msg("%s", infile);
} else {
bb_perror_msg_and_die("%s", infile);
}
}
- if (n == 0) {
- break;
- }
- if ((size_t)n == bs) {
+ if ((size_t)n == ibs) {
in_full++;
} else {
in_part++;
+ if (sync_flag) {
+ memset(ibuf + n, '\0', ibs - n);
+ n = ibs;
+ }
}
- if (sync_flag) {
- memset(buf + n, '\0', bs - n);
- n = bs;
+ if (twobufs_flag) {
+ char *tmp = ibuf;
+ while (n) {
+ size_t d = obs - oc;
+
+ if (d > n) d = n;
+ memcpy(obuf + oc, tmp, d);
+ n -= d;
+ tmp += d;
+ oc += d;
+ if (oc == obs) {
+ if (bb_full_write(ofd, obuf, obs) < 0) {
+ bb_perror_msg_and_die("%s", outfile);
+ }
+ out_full++;
+ oc = 0;
+ }
+ }
+ } else {
+ if ((n = bb_full_write(ofd, ibuf, n)) < 0) {
+ bb_perror_msg_and_die("%s", outfile);
+ }
+ if (n == ibs) out_full++;
+ else out_part++;
}
- n = bb_full_write(ofd, buf, n);
- if (n < 0) {
+ }
+
+ if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
+ if (bb_full_write(ofd, obuf, oc) < 0) {
bb_perror_msg_and_die("%s", outfile);
}
- if ((size_t)n == bs) {
- out_full++;
- } else {
- out_part++;
- }
+ out_part++;
}
-
if (close (ifd) < 0) {
bb_perror_msg_and_die("%s", infile);
}