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authorRob Landley <rob@landley.net>2009-01-05 01:05:43 -0600
committerRob Landley <rob@landley.net>2009-01-05 01:05:43 -0600
commitb15b8fa99ae53396145ea540106b74d37797f774 (patch)
tree1b16efb7c111d9ef52378b5765cb585d5eb01c79 /toys/cksum.c
parent2f638c397a916399049ac0adaf32a53f635d31bc (diff)
downloadtoybox-b15b8fa99ae53396145ea540106b74d37797f774.tar.gz
Add -N, -I, -L, and -P options to cksum.
Diffstat (limited to 'toys/cksum.c')
-rw-r--r--toys/cksum.c33
1 files changed, 23 insertions, 10 deletions
diff --git a/toys/cksum.c b/toys/cksum.c
index a54738cc..9b616671 100644
--- a/toys/cksum.c
+++ b/toys/cksum.c
@@ -6,18 +6,21 @@
*
* See http://www.opengroup.org/onlinepubs/009695399/utilities/cksum.html
-USE_CKSUM(NEWTOY(cksum, "F", TOYFLAG_BIN))
+USE_CKSUM(NEWTOY(cksum, "IPLN", TOYFLAG_BIN))
config CKSUM
bool "cksum"
default y
help
- usage: cksum [-F] [file...]
+ usage: cksum [-FL] [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.
- -F Start with 0xffffffff instead of 0.
+ -L Little endian (defaults to big endian)
+ -P Skip pre-inversion
+ -I Skip post-inversion
+ -N No length
*/
#include "toys.h"
@@ -28,16 +31,24 @@ DEFINE_GLOBALS(
#define TT this.cksum
-static unsigned cksum(unsigned crc, unsigned char c)
+static unsigned cksum_be(unsigned crc, unsigned char 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);
+}
+
static void do_cksum(int fd, char *name)
{
- unsigned crc = toys.optflags ? 0xffffffff : 0;
+ unsigned crc = (toys.optflags&4) ? 0 : 0xffffffff;
uint64_t llen = 0, llen2;
+ unsigned (*cksum)(unsigned crc, unsigned char c);
+
+ cksum = (toys.optflags&2) ? cksum_le : cksum_be;
// CRC the data
for (;;) {
@@ -57,18 +68,20 @@ static void do_cksum(int fd, char *name)
// CRC the length
llen2 = llen;
- while (llen) {
- crc = cksum(crc, llen);
- llen >>= 8;
+ if (!(toys.optflags&1)) {
+ while (llen) {
+ crc = cksum(crc, llen);
+ llen >>= 8;
+ }
}
- printf("%u %"PRIu64, ~crc, llen2);
+ 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);
+ crc_init(TT.crc_table, toys.optflags&2);
loopfiles(toys.optargs, do_cksum);
}