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-rw-r--r--toys/posix/cksum.c107
1 files changed, 52 insertions, 55 deletions
diff --git a/toys/posix/cksum.c b/toys/posix/cksum.c
index 3e27b4cb..1192077c 100644
--- a/toys/posix/cksum.c
+++ b/toys/posix/cksum.c
@@ -1,6 +1,4 @@
-/* vi: set sw=4 ts=4:
- *
- * cksum.c - produce crc32 checksum value for each input
+/* cksum.c - produce crc32 checksum value for each input
*
* Copyright 2008 Rob Landley <rob@landley.net>
*
@@ -9,78 +7,77 @@
USE_CKSUM(NEWTOY(cksum, "IPLN", TOYFLAG_BIN))
config CKSUM
- bool "cksum"
- default y
- help
- usage: cksum [-IPLN] [file...]
-
- For each file, output crc32 checksum value, length and name of file.
- If no files listed, copy from stdin. Filename "-" is a synonym for stdin.
-
- -L Little endian (defaults to big endian)
- -P Pre-inversion
- -I Skip post-inversion
- -N Do not include length in CRC calculation
+ bool "cksum"
+ default y
+ help
+ usage: cksum [-IPLN] [file...]
+
+ For each file, output crc32 checksum value, length and name of file.
+ If no files listed, copy from stdin. Filename "-" is a synonym for stdin.
+
+ -L Little endian (defaults to big endian)
+ -P Pre-inversion
+ -I Skip post-inversion
+ -N Do not include length in CRC calculation
*/
#define FOR_cksum
#include "toys.h"
GLOBALS(
- unsigned crc_table[256];
+ unsigned crc_table[256];
)
static unsigned cksum_be(unsigned crc, unsigned char c)
{
- return (crc<<8)^TT.crc_table[(crc>>24)^c];
+ return (crc<<8)^TT.crc_table[(crc>>24)^c];
}
static unsigned cksum_le(unsigned crc, unsigned char c)
{
- return TT.crc_table[(crc^c)&0xff] ^ (crc>>8);
+ return TT.crc_table[(crc^c)&0xff] ^ (crc>>8);
}
static void do_cksum(int fd, char *name)
{
- unsigned crc = (toys.optflags&4) ? 0xffffffff : 0;
- uint64_t llen = 0, llen2;
- unsigned (*cksum)(unsigned crc, unsigned char c);
-
-
- cksum = (toys.optflags&2) ? cksum_le : cksum_be;
- // CRC the data
-
- for (;;) {
- int len, i;
-
- len = read(fd, toybuf, sizeof(toybuf));
- if (len<0) {
- perror_msg("%s",name);
- toys.exitval = EXIT_FAILURE;
- }
- if (len<1) break;
-
- llen += len;
- for (i=0; i<len; i++) crc=cksum(crc, toybuf[i]);
- }
-
- // CRC the length
-
- llen2 = llen;
- if (!(toys.optflags&1)) {
- while (llen) {
- crc = cksum(crc, llen);
- llen >>= 8;
- }
- }
-
- printf("%u %"PRIu64, (toys.optflags&8) ? crc : ~crc, llen2);
- if (strcmp("-", name)) printf(" %s", name);
- xputc('\n');
+ unsigned crc = (toys.optflags&4) ? 0xffffffff : 0;
+ uint64_t llen = 0, llen2;
+ unsigned (*cksum)(unsigned crc, unsigned char c);
+
+ cksum = (toys.optflags&2) ? cksum_le : cksum_be;
+ // CRC the data
+
+ for (;;) {
+ int len, i;
+
+ len = read(fd, toybuf, sizeof(toybuf));
+ if (len<0) {
+ perror_msg("%s",name);
+ toys.exitval = EXIT_FAILURE;
+ }
+ if (len<1) break;
+
+ llen += len;
+ for (i=0; i<len; i++) crc=cksum(crc, toybuf[i]);
+ }
+
+ // CRC the length
+
+ llen2 = llen;
+ if (!(toys.optflags&1)) {
+ while (llen) {
+ crc = cksum(crc, llen);
+ llen >>= 8;
+ }
+ }
+
+ printf("%u %"PRIu64, (toys.optflags&8) ? crc : ~crc, llen2);
+ if (strcmp("-", name)) printf(" %s", name);
+ xputc('\n');
}
void cksum_main(void)
{
- crc_init(TT.crc_table, toys.optflags&2);
- loopfiles(toys.optargs, do_cksum);
+ crc_init(TT.crc_table, toys.optflags&2);
+ loopfiles(toys.optargs, do_cksum);
}