New applet cksum, from Rob Sullivan.
diff --git a/coreutils/Config.in b/coreutils/Config.in
index c77a1c9..5d2965b 100644
--- a/coreutils/Config.in
+++ b/coreutils/Config.in
@@ -52,6 +52,12 @@
chroot is used to change the root directory and run a command.
The default command is `/bin/sh'.
+config CONFIG_CKSUM
+ bool "cksum"
+ default n
+ help
+ cksum is used to calculate the CRC32 checksum of a file.
+
config CONFIG_CMP
bool "cmp"
default n
diff --git a/coreutils/Makefile.in b/coreutils/Makefile.in
index ff0e89b..24eee0b 100644
--- a/coreutils/Makefile.in
+++ b/coreutils/Makefile.in
@@ -18,6 +18,7 @@
COREUTILS-$(CONFIG_CHMOD) += chmod.o
COREUTILS-$(CONFIG_CHOWN) += chown.o
COREUTILS-$(CONFIG_CHROOT) += chroot.o
+COREUTILS-$(CONFIG_CKSUM) += cksum.o
COREUTILS-$(CONFIG_CMP) += cmp.o
COREUTILS-$(CONFIG_COMM) += comm.o
COREUTILS-$(CONFIG_CP) += cp.o
diff --git a/coreutils/cksum.c b/coreutils/cksum.c
new file mode 100644
index 0000000..194ea7d
--- /dev/null
+++ b/coreutils/cksum.c
@@ -0,0 +1,56 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * cksum - calculate the CRC32 checksum of a file
+ *
+ * Copyright (C) 2006 by Rob Sullivan, with ideas from code by Walter Harms
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include "busybox.h"
+
+int cksum_main(int argc, char **argv) {
+
+ uint32_t *crc32_table = bb_crc32_filltable(1);
+
+ FILE *fp;
+ uint32_t crc;
+ long length, filesize;
+ int bytes_read;
+ char *cp;
+ RESERVE_CONFIG_BUFFER(buf, BUFSIZ);
+ int inp_stdin = (argc == optind) ? 1 : 0;
+
+ do {
+ fp = bb_wfopen_input((inp_stdin) ? bb_msg_standard_input : *++argv);
+
+ crc = 0;
+ length = 0;
+
+ while ((bytes_read = fread(buf, 1, BUFSIZ, fp)) > 0) {
+ cp = buf;
+ length += bytes_read;
+ while (bytes_read--)
+ crc = (crc << 8) ^ crc32_table[((crc >> 24) ^ (*cp++)) & 0xffL];
+ }
+
+ filesize = length;
+
+ for (; length; length >>= 8)
+ crc = (crc << 8) ^ crc32_table[((crc >> 24) ^ length) & 0xffL];
+ crc ^= 0xffffffffL;
+
+ if (inp_stdin) {
+ printf("%"PRIu32" %li\n", crc, filesize);
+ break;
+ }
+
+ printf("%"PRIu32" %li %s\n", crc, filesize, *argv);
+ fclose(fp);
+ } while (*(argv+1));
+
+ return EXIT_SUCCESS;
+}