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|
This patch adds support of ibs= and obs= to dd.
----
Hideki IWAMOTO h-iwamoto@kit.hi-ho.ne.jp
--- a/include/usage.h 29 Mar 2004 08:20:08 -0000 1.198
+++ b/include/usage.h 4 Apr 2004 07:15:21 -0000
@@ -309,13 +309,15 @@
"64\n"
#define dd_trivial_usage \
- "[if=FILE] [of=FILE] [bs=N] [count=N] [skip=N]\n" \
- "\t [seek=N] [conv=notrunc|noerror|sync]"
+ "[if=FILE] [of=FILE] [ibs=N] [obs=N] [bs=N] [count=N]\n" \
+ "\t [skip=N] [seek=N] [conv=notrunc|noerror|sync]"
#define dd_full_usage \
"Copy a file, converting and formatting according to options\n\n" \
"\tif=FILE\t\tread from FILE instead of stdin\n" \
"\tof=FILE\t\twrite to FILE instead of stdout\n" \
- "\tbs=N\t\tread and write N bytes at a time\n" \
+ "\tibs=N\t\tread N bytes at a time\n" \
+ "\tobs=N\t\twrite N bytes at a time\n" \
+ "\tbs=N\t\tforce ibs=N and obs=N\n" \
"\tcount=N\t\tcopy only N input blocks\n" \
"\tskip=N\t\tskip N input blocks\n" \
"\tseek=N\t\tskip N output blocks\n" \
@@ -323,6 +325,8 @@
"\tconv=noerror\tcontinue after read errors\n" \
"\tconv=sync\tpad blocks with zeros\n" \
"\n" \
+ "If the bs= expr operand is not specified, the input is processed and collected\n" \
+ "into full-sized output blocks until the end of the input is reached.\n" \
"Numbers may be suffixed by c (x1), w (x2), b (x512), kD (x1000), k (x1024),\n" \
"MD (x1000000), M (x1048576), GD (x1000000000) or G (x1073741824)."
#define dd_example_usage \
--- a/coreutils/dd.c 30 Jan 2004 22:24:32 -0000 1.55
+++ b/coreutils/dd.c 4 Apr 2004 07:15:21 -0000
@@ -30,6 +30,10 @@
#include <fcntl.h>
#include "busybox.h"
+#define C_NOERROR 0x0001
+#define C_TRUNC 0x0002
+#define C_SYNC 0x0004
+#define C_TWOBUFS 0x0008
static const struct suffix_mult dd_suffixes[] = {
{ "c", 1 },
@@ -51,13 +55,13 @@
size_t in_full = 0;
size_t in_part = 0;
size_t count = -1;
- size_t bs = 512;
+ size_t ibs = 512;
+ size_t obs = 512;
+ size_t oc = 0;
ssize_t n;
off_t seek = 0;
off_t skip = 0;
- int sync_flag = FALSE;
- int noerror = FALSE;
- int trunc_flag = TRUE;
+ unsigned int dd_flags = C_TWOBUFS | C_TRUNC;
int oflag;
int ifd;
int ofd;
@@ -65,11 +69,18 @@
const char *infile = NULL;
const char *outfile = NULL;
char *buf;
+ char *ibuf;
+ char *obuf;
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 (strncmp("ibs=", argv[i], 4) == 0)
+ ibs = bb_xparse_number(argv[i]+4, dd_suffixes);
+ else if (strncmp("obs=", argv[i], 4) == 0)
+ obs = bb_xparse_number(argv[i]+4, dd_suffixes);
+ else if (strncmp("bs=", argv[i], 3) == 0) {
+ ibs = obs = bb_xparse_number(argv[i]+3, dd_suffixes);
+ dd_flags &= ~C_TWOBUFS;
+ } else if (strncmp("count=", argv[i], 6) == 0)
count = bb_xparse_number(argv[i]+6, dd_suffixes);
else if (strncmp("seek=", argv[i], 5) == 0)
seek = bb_xparse_number(argv[i]+5, dd_suffixes);
@@ -83,13 +94,13 @@
buf = argv[i]+5;
while (1) {
if (strncmp("notrunc", buf, 7) == 0) {
- trunc_flag = FALSE;
+ dd_flags &= ~C_TRUNC;
buf += 7;
} else if (strncmp("sync", buf, 4) == 0) {
- sync_flag = TRUE;
+ dd_flags |= C_SYNC;
buf += 4;
} else if (strncmp("noerror", buf, 7) == 0) {
- noerror = TRUE;
+ dd_flags |= C_NOERROR;
buf += 7;
} else {
bb_error_msg_and_die("invalid conversion `%s'", argv[i]+5);
@@ -103,7 +114,12 @@
bb_show_usage();
}
- buf = xmalloc(bs);
+ ibuf = xmalloc(ibs);
+
+ if (dd_flags & C_TWOBUFS)
+ obuf = xmalloc(obs);
+ else
+ obuf = ibuf;
if (infile != NULL) {
ifd = bb_xopen(infile, O_RDONLY);
@@ -115,7 +131,7 @@
if (outfile != NULL) {
oflag = O_WRONLY | O_CREAT;
- if (!seek && trunc_flag) {
+ if (!seek && (dd_flags & C_TRUNC)) {
oflag |= O_TRUNC;
}
@@ -123,8 +139,8 @@
bb_perror_msg_and_die("%s", outfile);
}
- if (seek && trunc_flag) {
- if (ftruncate(ofd, seek * bs) < 0) {
+ if (seek && (dd_flags & C_TRUNC)) {
+ if (ftruncate(ofd, seek * obs) < 0) {
struct stat st;
if (fstat (ofd, &st) < 0 || S_ISREG (st.st_mode) ||
@@ -139,52 +155,88 @@
}
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);
}
}
while (in_full + in_part != count) {
- if (noerror) {
+ if (dd_flags & C_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;
+ if (dd_flags & C_NOERROR) {
+ n = ibs;
bb_perror_msg("%s", infile);
} else {
bb_perror_msg_and_die("%s", infile);
}
}
- if (n == 0) {
- break;
- }
- if (n == bs) {
+ if (n == ibs) {
in_full++;
} else {
in_part++;
+ if (dd_flags & C_SYNC) {
+ memset(ibuf + n, '\0', ibs - n);
+ n = ibs;
+ }
}
- if (sync_flag) {
- memset(buf + n, '\0', bs - n);
- n = bs;
+
+ if (dd_flags & C_TWOBUFS) {
+ size_t d;
+ char *tmp = ibuf;
+
+ while (n) {
+ 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 (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 (oc) {
+ if (bb_full_write(ofd, obuf, oc) < 0) {
bb_perror_msg_and_die("%s", outfile);
}
- if (n == bs) {
- out_full++;
- } else {
- out_part++;
- }
+ out_part++;
}
if (close (ifd) < 0) {
|
