diff options
Diffstat (limited to 'coreutils')
| -rw-r--r-- | coreutils/Config.in | 6 | ||||
| -rw-r--r-- | coreutils/Makefile.in | 1 | ||||
| -rw-r--r-- | coreutils/cksum.c | 56 |
3 files changed, 63 insertions, 0 deletions
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 @@ config CONFIG_CHROOT 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-$(CONFIG_CHGRP) += chgrp.o COREUTILS-$(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; +} |