/* dd.c - program to convert and copy a file.
*
* Copyright 2013 Ashwini Kumar <ak.ashwini@gmail.com>
* Copyright 2013 Kyungwan Han <asura321@gmail.com>
*
* See http://opengroup.org/onlinepubs/9699919799/utilities/dd.html
USE_DD(NEWTOY(dd, NULL, TOYFLAG_USR|TOYFLAG_BIN))
config DD
bool "dd"
default n
help
usage: dd [if=FILE] [of=FILE] [ibs=N] [obs=N] [bs=N] [count=N] [skip=N]
[seek=N] [conv=notrunc|noerror|sync|fsync] [status=noxfer|none]
Options:
if=FILE Read from FILE instead of stdin
of=FILE Write to FILE instead of stdout
bs=N Read and write N bytes at a time
ibs=N Read N bytes at a time
obs=N Write N bytes at a time
count=N Copy only N input blocks
skip=N Skip N input blocks
seek=N Skip N output blocks
conv=notrunc Don't truncate output file
conv=noerror Continue after read errors
conv=sync Pad blocks with zeros
conv=fsync Physically write data out before finishing
status=noxfer Don't show transfer rate
status=none Don't show transfer rate or records in/out
Numbers may be suffixed by c (*1), w (*2), b (*512), kD (*1000), k (*1024),
MD (*1000*1000), M (*1024*1024), GD (*1000*1000*1000) or G (*1024*1024*1024).
*/
#define FOR_dd
#include "toys.h"
GLOBALS(
int show_xfer;
int show_records;
unsigned long long bytes, c_count, in_full, in_part, out_full, out_part;
struct timeval start;
struct {
char *name;
int fd;
unsigned char *buff, *bp;
long sz, count;
unsigned long long offset;
} in, out;
);
#define C_CONV 0x0000
#define C_BS 0x0001
#define C_COUNT 0x0002
#define C_IBS 0x0004
#define C_OBS 0x0008
#define C_IF 0x0010
#define C_OF 0x0020
#define C_SEEK 0x0040
#define C_SKIP 0x0080
#define C_SYNC 0x0100
#define C_FSYNC 0x0200
#define C_NOERROR 0x0400
#define C_NOTRUNC 0x0800
#define C_STATUS 0x1000
struct pair {
char *name;
unsigned val;
};
static struct pair suffixes[] = {
{ "c", 1 }, { "w", 2 }, { "b", 512 },
{ "kD", 1000 }, { "k", 1024 }, { "K", 1024 },
{ "MD", 1000000 }, { "M", 1048576 },
{ "GD", 1000000000 }, { "G", 1073741824 }
};
static struct pair clist[] = {
{ "fsync", C_FSYNC },
{ "noerror", C_NOERROR },
{ "notrunc", C_NOTRUNC },
{ "sync", C_SYNC },
};
static struct pair operands[] = {
// keep the array sorted by name, bsearch() can be used.
{ "bs", C_BS },
{ "conv", C_CONV },
{ "count", C_COUNT },
{ "ibs", C_IBS },
{ "if", C_IF },
{ "obs", C_OBS },
{ "of", C_OF },
{ "seek", C_SEEK },
{ "skip", C_SKIP },
{ "status", C_STATUS},
};
static unsigned long long strsuftoll(char *arg, int def, unsigned long long max)
{
unsigned long long result;
char *p = arg;
int i, idx = -1;
while (isspace(*p)) p++;
if (*p == '-') error_exit("invalid number '%s'", arg);
errno = 0;
result = strtoull(p, &p, 0);
if (errno == ERANGE || result > max || result < def)
perror_exit("invalid number '%s'", arg);
if (*p != '\0') {
for (i = 0; i < ARRAY_LEN(suffixes); i++)
if (!strcmp(p, suffixes[i].name)) idx = i;
if (idx == -1 || (max/suffixes[idx].val < result))
error_exit("invalid number '%s'", arg);
result *= suffixes[idx].val;
}
return result;
}
static void status()
{
double seconds;
struct timeval now;
gettimeofday(&now, NULL);
seconds = ((now.tv_sec * 1000000 + now.tv_usec) -
(TT.start.tv_sec * 1000000 + TT.start.tv_usec))/1000000.0;
if (TT.show_records)
fprintf(stderr, "%llu+%llu records in\n%llu+%llu records out\n",
TT.in_full, TT.in_part, TT.out_full, TT.out_part);
if (TT.show_xfer) {
human_readable(toybuf, TT.bytes, HR_SPACE|HR_B);
fprintf(stderr, "%llu bytes (%s) copied, ", TT.bytes, toybuf);
human_readable(toybuf, TT.bytes/seconds, HR_SPACE|HR_B);
fprintf(stderr, "%f s, %s/s\n", seconds, toybuf);
}
}
static void write_out(int all)
{
TT.out.bp = TT.out.buff;
while (TT.out.count) {
ssize_t nw = writeall(TT.out.fd, TT.out.bp, ((all)? TT.out.count : TT.out.sz));
all = 0; //further writes will be on obs
if (nw <= 0) perror_exit("%s: write error", TT.out.name);
if (nw == TT.out.sz) TT.out_full++;
else TT.out_part++;
TT.out.count -= nw;
TT.out.bp += nw;
TT.bytes += nw;
if (TT.out.count < TT.out.sz) break;
}
if (TT.out.count) memmove(TT.out.buff, TT.out.bp, TT.out.count); //move remainder to front
}
static int comp(const void *a, const void *b) //const to shut compiler up
{
return strcmp(((struct pair*)a)->name, ((struct pair*)b)->name);
}
void dd_main()
{
struct pair *res, key;
char *arg;
long sz;
TT.show_xfer = TT.show_records = 1;
TT.in.sz = TT.out.sz = 512; //default io block size
while (*toys.optargs) {
if (!(arg = strchr(*toys.optargs, '='))) error_exit("unknown arg %s", *toys.optargs);
*arg++ = '\0';
if (!*arg) help_exit(0);
key.name = *toys.optargs;
if (!(res = bsearch(&key, operands, ARRAY_LEN(operands), sizeof(struct pair),
comp))) error_exit("unknown arg %s", key.name);
toys.optflags |= res->val;
switch (res->val) {
case C_BS:
TT.in.sz = TT.out.sz = strsuftoll(arg, 1, LONG_MAX);
break;
case C_IBS:
sz = strsuftoll(arg, 1, LONG_MAX);
if (!(toys.optflags & C_BS)) TT.in.sz = sz;
break;
case C_OBS:
sz = strsuftoll(arg, 1, LONG_MAX);
if (!(toys.optflags & C_BS)) TT.out.sz = sz;
break;
case C_COUNT:
TT.c_count = strsuftoll(arg, 0, ULLONG_MAX);
break;
case C_IF:
TT.in.name = arg;
break;
case C_OF:
TT.out.name = arg;
break;
case C_SEEK:
TT.out.offset = strsuftoll(arg, 0, ULLONG_MAX);
break;
case C_SKIP:
TT.in.offset = strsuftoll(arg, 0, ULLONG_MAX);
break;
case C_STATUS:
if (!strcmp(arg, "noxfer")) TT.show_xfer = 0;
else if (!strcmp(arg, "none")) TT.show_xfer = TT.show_records = 0;
else error_exit("unknown status '%s'", arg);
break;
case C_CONV:
while (arg) {
key.name = strsep(&arg, ",");
if (!(res = bsearch(&key, clist, ARRAY_LEN(clist),
sizeof(struct pair), comp)))
error_exit("unknown conversion %s", key.name);
toys.optflags |= res->val;
}
break;
}
toys.optargs++;
}
signal(SIGINT, generic_signal);
signal(SIGUSR1, generic_signal);
gettimeofday(&TT.start, NULL);
/* for C_BS, in/out is done as it is. so only in.sz is enough.
* With Single buffer there will be overflow in a read following partial read
*/
TT.in.buff = TT.out.buff = xmalloc(TT.in.sz
+ ((toys.optflags & C_BS) ? 0 : TT.out.sz));
TT.in.bp = TT.out.bp = TT.in.buff;
//setup input
if (!TT.in.name) TT.in.name = "stdin";
else TT.in.fd = xopenro(TT.in.name);
//setup output
if (!TT.out.name) {
TT.out.name = "stdout";
TT.out.fd = 1;
} else TT.out.fd = xcreate(TT.out.name,
O_WRONLY|O_CREAT|(O_TRUNC*!(toys.optflags&C_NOTRUNC)), 0666);
// Implement skip=
if (TT.in.offset) {
if (lseek(TT.in.fd, (off_t)(TT.in.offset * TT.in.sz), SEEK_CUR) < 0) {
while (TT.in.offset--) {
ssize_t n = read(TT.in.fd, TT.in.bp, TT.in.sz);
if (n < 0) {
perror_msg("%s", TT.in.name);
if (toys.optflags & C_NOERROR) status();
else return;
} else if (!n) {
xprintf("%s: Can't skip\n", TT.in.name);
return;
}
}
}
}
if (TT.out.offset)
xlseek(TT.out.fd, TT.out.offset * (off_t)TT.out.sz, SEEK_CUR);
if ((toys.optflags&C_SEEK) && !(toys.optflags & C_NOTRUNC))
if (ftruncate(TT.out.fd, TT.out.offset * TT.out.sz))
perror_exit("ftruncate");
while (!(toys.optflags & C_COUNT) || (TT.in_full + TT.in_part) < TT.c_count) {
ssize_t n;
// Show progress and exit on SIGINT or just continue on SIGUSR1.
if (toys.signal) {
status();
if (toys.signal==SIGINT) exit_signal(toys.signal);
toys.signal = 0;
}
TT.in.bp = TT.in.buff + TT.in.count;
if (toys.optflags & C_SYNC) memset(TT.in.bp, 0, TT.in.sz);
if (!(n = read(TT.in.fd, TT.in.bp, TT.in.sz))) break;
if (n < 0) {
if (errno == EINTR) continue;
//read error case.
perror_msg("%s: read error", TT.in.name);
if (!(toys.optflags & C_NOERROR)) exit(1);
status();
xlseek(TT.in.fd, TT.in.sz, SEEK_CUR);
if (!(toys.optflags & C_SYNC)) continue;
// if SYNC, then treat as full block of nuls
n = TT.in.sz;
}
if (n == TT.in.sz) {
TT.in_full++;
TT.in.count += n;
} else {
TT.in_part++;
if (toys.optflags & C_SYNC) TT.in.count += TT.in.sz;
else TT.in.count += n;
}
TT.out.count = TT.in.count;
if (toys.optflags & C_BS) {
write_out(1);
TT.in.count = 0;
continue;
}
if (TT.in.count >= TT.out.sz) {
write_out(0);
TT.in.count = TT.out.count;
}
}
if (TT.out.count) write_out(1); //write any remaining input blocks
if (toys.optflags & C_FSYNC && fsync(TT.out.fd) < 0)
perror_exit("%s: fsync fail", TT.out.name);
close(TT.in.fd);
close(TT.out.fd);
if (TT.in.buff) free(TT.in.buff);
status();
}