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/* (C) 2011-2012 Sebastian Krahmer all rights reserved.
*
* Optimized dd, to speed up backups etc.
*
* Permission has been granted to release this code under MIT/X.
* The original code is at https://github.com/stealth/odd. This
* version of the code has been modified by sin@2f30.org.
*/
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/vfs.h>
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "util.h"
struct dd_config {
const char *in, *out;
uint64_t skip, seek, count, b_in, b_out, rec_in, rec_out;
off_t fsize;
blksize_t bs;
char quiet, nosync, direct;
int saved_errno;
time_t t_start, t_end;
};
static int sigint = 0;
static int
prepare_copy(struct dd_config *ddc, int *ifd, int *ofd)
{
struct stat st;
int fli = O_RDONLY|O_LARGEFILE|O_NOCTTY, flo = O_WRONLY|O_LARGEFILE|O_NOATIME|O_NOCTTY;
uid_t euid = 0;
long pagesize;
if (ddc->direct) {
fli |= O_DIRECT;
flo |= O_DIRECT;
}
if (stat(ddc->in, &st) < 0) {
ddc->saved_errno = errno;
return -1;
}
euid = geteuid();
if (!euid || st.st_uid == euid)
fli |= O_NOATIME;
if ((*ifd = open(ddc->in, fli)) < 0) {
ddc->saved_errno = errno;
return -1;
}
ddc->fsize = st.st_size;
/* If "bsize" is not given, use optimum of both FS' */
if (!ddc->bs) {
struct statfs fst;
memset(&fst, 0, sizeof(fst));
pagesize = sysconf(_SC_PAGESIZE);
if (pagesize <= 0)
pagesize = 0x1000;
if (statfs(ddc->out, &fst) < 0 || fst.f_bsize == 0)
fst.f_bsize = pagesize;
if ((unsigned long)fst.f_bsize > (unsigned long)st.st_blksize)
ddc->bs = fst.f_bsize;
else
ddc->bs = st.st_blksize;
if (ddc->bs == 0)
ddc->bs = pagesize;
}
/* check if device or regular file */
if (!S_ISREG(st.st_mode)) {
if (S_ISBLK(st.st_mode)) {
if (ioctl(*ifd, BLKGETSIZE64, &ddc->fsize) < 0) {
ddc->saved_errno = errno;
close(*ifd);
return -1;
}
} else {
ddc->fsize = (off_t)-1;
if (ddc->count)
ddc->fsize = ddc->count*ddc->bs;
}
}
/* skip and seek are in block items */
ddc->skip *= ddc->bs;
ddc->seek *= ddc->bs;
/* skip more bytes than are inside source file? */
if (ddc->fsize != (off_t)-1 && ddc->skip >= (uint64_t)ddc->fsize) {
ddc->saved_errno = EINVAL;
close(*ifd);
return -1;
}
if (!ddc->seek)
flo |= O_CREAT|O_TRUNC;
if ((*ofd = open(ddc->out, flo, st.st_mode)) < 0) {
ddc->saved_errno = errno;
close(*ifd);
return -1;
}
lseek(*ifd, ddc->skip, SEEK_SET);
lseek(*ofd, ddc->seek, SEEK_SET);
posix_fadvise(*ifd, ddc->skip, 0, POSIX_FADV_SEQUENTIAL);
posix_fadvise(*ofd, 0, 0, POSIX_FADV_DONTNEED);
/* count is in block items too */
ddc->count *= ddc->bs;
/* If no count is given, its the filesize minus skip offset */
if (ddc->count == 0)
ddc->count = ddc->fsize - ddc->skip;
return 0;
}
static int
copy_splice(struct dd_config *ddc)
{
int ifd, ofd, p[2] = {-1, -1};
ssize_t r = 0;
size_t n = 0;
fd_set rfd, wfd;
if (prepare_copy(ddc, &ifd, &ofd) < 0)
return -1;
if (pipe(p) < 0) {
ddc->saved_errno = errno;
close(ifd); close(ofd);
close(p[0]); close(p[1]);
return -1;
}
#ifdef F_SETPIPE_SZ
for (n = 29; n >= 20; --n) {
if (fcntl(p[0], F_SETPIPE_SZ, 1<<n) != -1)
break;
}
#endif
n = ddc->bs;
for (;ddc->b_out != ddc->count && !sigint;) {
FD_ZERO(&rfd);
FD_ZERO(&wfd);
FD_SET(ifd, &rfd);
FD_SET(ofd, &wfd);
r = select(ifd > ofd ? ifd + 1 : ofd + 1, &rfd, &wfd, NULL, NULL);
if (r < 0) {
ddc->saved_errno = errno;
break;
}
if (FD_ISSET(ifd, &rfd) == 1 && FD_ISSET(ofd, &wfd) == 1) {
if (n > ddc->count - ddc->b_out)
n = ddc->count - ddc->b_out;
r = splice(ifd, NULL, p[1], NULL, n, SPLICE_F_MORE);
if (r <= 0) {
ddc->saved_errno = errno;
break;
}
++ddc->rec_in;
r = splice(p[0], NULL, ofd, NULL, r, SPLICE_F_MORE);
if (r <= 0) {
ddc->saved_errno = errno;
break;
}
ddc->b_out += r;
++ddc->rec_out;
}
}
close(ifd);
close(ofd);
close(p[0]);
close(p[1]);
if (r < 0)
return -1;
return 0;
}
static int
copy(struct dd_config *ddc)
{
int r = 0;
ddc->t_start = time(NULL);
r = copy_splice(ddc);
ddc->t_end = time(NULL);
/* avoid div by zero */
if (ddc->t_start == ddc->t_end)
++ddc->t_end;
return r;
}
static void
print_stat(const struct dd_config *ddc)
{
if (ddc->quiet)
return;
fprintf(stderr, "%"PRIu64" records in\n", ddc->rec_in);
fprintf(stderr, "%"PRIu64" records out\n", ddc->rec_out);
fprintf(stderr, "%"PRIu64" bytes (%"PRIu64" MB) copied", ddc->b_out,
ddc->b_out/(1<<20));
fprintf(stderr, ", %lu s, %f MB/s\n",
(unsigned long)ddc->t_end - ddc->t_start,
((double)(ddc->b_out/(1<<20)))/(ddc->t_end - ddc->t_start));
}
static void
sig_int(int unused)
{
(void) unused;
fprintf(stderr, "SIGINT! Aborting ...\n");
sigint = 1;
}
static void
usage(void)
{
eprintf("usage: %s [-h] [if=infile] [of=outfile] [bs[=N]] [seek=N] "
"[skip=N] [count=N] [direct] [quiet] [nosync]\n", argv0);
}
int
main(int argc, char *argv[])
{
int i = 0;
char buf[1024];
struct dd_config config;
argv0 = argv[0];
memset(&config, 0, sizeof(config));
config.bs = 1<<16;
config.in = "/dev/stdin";
config.out = "/dev/stdout";
/* emulate 'dd' argument parsing */
for (i = 1; i < argc; ++i) {
memset(buf, 0, sizeof(buf));
if (sscanf(argv[i], "if=%1023s", buf) == 1)
config.in = strdup(buf);
else if (sscanf(argv[i], "of=%1023s", buf) == 1)
config.out = strdup(buf);
else if (sscanf(argv[i], "skip=%1023s", buf) == 1)
config.skip = estrtoul(buf, 0);
else if (sscanf(argv[i], "seek=%1023s", buf) == 1)
config.seek = estrtoul(buf, 0);
else if (sscanf(argv[i], "count=%1023s", buf) == 1)
config.count = estrtoul(buf, 0);
else if (strcmp(argv[i], "direct") == 0)
config.direct = 1;
else if (sscanf(argv[i], "bs=%1023s", buf) == 1)
config.bs = estrtoul(buf, 0);
else if (strcmp(argv[i], "bs") == 0)
config.bs = 0;
else if (strcmp(argv[i], "quiet") == 0)
config.quiet = 1;
else if (strcmp(argv[i], "nosync") == 0)
config.nosync = 1;
else if (strcmp(argv[i], "-h") == 0)
usage();
}
if (!config.in || !config.out)
usage();
signal(SIGPIPE, SIG_IGN);
signal(SIGINT, sig_int);
if (copy(&config) < 0)
weprintf("copy:");
print_stat(&config);
if (config.nosync == 0)
sync();
return config.saved_errno;
}