busybox/coreutils/split.c

142 lines
3.0 KiB
C
Raw Normal View History

/* vi: set sw=4 ts=4: */
/*
* split - split a file into pieces
* Copyright (c) 2007 Bernhard Fischer
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
/* BB_AUDIT: SUSv3 compliant
* SUSv3 requirements:
* http://www.opengroup.org/onlinepubs/009695399/utilities/split.html
*/
#include "libbb.h"
2007-03-26 16:16:31 +05:30
static const struct suffix_mult split_suffices[] = {
#if ENABLE_FEATURE_SPLIT_FANCY
2007-03-26 16:16:31 +05:30
{ "b", 512 },
#endif
2007-03-26 16:16:31 +05:30
{ "k", 1024 },
{ "m", 1024*1024 },
#if ENABLE_FEATURE_SPLIT_FANCY
2007-03-26 16:16:31 +05:30
{ "g", 1024*1024*1024 },
#endif
{ }
2007-03-26 16:16:31 +05:30
};
/* Increment the suffix part of the filename.
* Returns NULL if we are out of filenames.
*/
static char *next_file(char *old, unsigned suffix_len)
{
size_t end = strlen(old);
unsigned i = 1;
char *curr;
do {
curr = old + end - i;
if (*curr < 'z') {
2007-03-26 16:16:31 +05:30
*curr += 1;
break;
}
i++;
if (i > suffix_len) {
return NULL;
}
*curr = 'a';
} while (1);
return old;
}
#define read_buffer bb_common_bufsiz1
enum { READ_BUFFER_SIZE = COMMON_BUFSIZE - 1 };
#define SPLIT_OPT_l (1<<0)
#define SPLIT_OPT_b (1<<1)
2007-03-26 16:16:31 +05:30
#define SPLIT_OPT_a (1<<2)
int split_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int split_main(int argc, char **argv)
{
unsigned suffix_len = 2;
char *pfx;
char *count_p;
const char *sfx;
off_t cnt = 1000;
off_t remaining = 0;
unsigned opt;
ssize_t bytes_read, to_write;
char *src;
opt_complementary = "?2";
opt = getopt32(argv, "l:b:a:", &count_p, &count_p, &sfx);
if (opt & SPLIT_OPT_l)
cnt = xatoul(count_p);
if (opt & SPLIT_OPT_b)
cnt = xatoul_sfx(count_p, split_suffices);
if (opt & SPLIT_OPT_a)
suffix_len = xatou(sfx);
sfx = "x";
argv += optind;
if (argv[0]) {
if (argv[1])
sfx = argv[1];
xmove_fd(xopen(argv[0], O_RDONLY), 0);
} else {
argv[0] = (char *) bb_msg_standard_input;
}
if (NAME_MAX < strlen(sfx) + suffix_len)
bb_error_msg_and_die("suffix too long");
{
char *char_p = xzalloc(suffix_len + 1);
memset(char_p, 'a', suffix_len);
pfx = xasprintf("%s%s", sfx, char_p);
if (ENABLE_FEATURE_CLEAN_UP)
free(char_p);
}
while (1) {
bytes_read = safe_read(0, read_buffer, READ_BUFFER_SIZE);
if (!bytes_read)
break;
if (bytes_read < 0)
bb_simple_perror_msg_and_die(argv[0]);
src = read_buffer;
do {
if (!remaining) {
if (!pfx)
bb_error_msg_and_die("suffixes exhausted");
xmove_fd(xopen(pfx, O_WRONLY | O_CREAT | O_TRUNC), 1);
pfx = next_file(pfx, suffix_len);
remaining = cnt;
}
if (opt & SPLIT_OPT_b) {
/* split by bytes */
to_write = (bytes_read < remaining) ? bytes_read : remaining;
remaining -= to_write;
} else {
/* split by lines */
/* can be sped up by using _memrchr_
* and writing many lines at once... */
char *end = memchr(src, '\n', bytes_read);
if (end) {
--remaining;
to_write = end - src + 1;
} else {
to_write = bytes_read;
}
}
xwrite(1, src, to_write);
bytes_read -= to_write;
src += to_write;
} while (bytes_read);
}
return EXIT_SUCCESS;
}