New applet cksum, from Rob Sullivan.

git-svn-id: svn://busybox.net/trunk/busybox@14917 69ca8d6d-28ef-0310-b511-8ec308f3f277

5 files changed, 69 insertions, 0 deletions

diff --git a/coreutils/Config.in b/coreutils/Config.in
index c77a1c90f..5d2965b47 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 ff0e89b4d..24eee0b91 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 000000000..194ea7d2a
--- /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;
+}
diff --git a/include/applets.h b/include/applets.h
index 12d438cea..059472248 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -70,6 +70,7 @@ USE_CHMOD(APPLET(chmod, chmod_main, _BB_DIR_BIN, _BB_SUID_NEVER))
 USE_CHOWN(APPLET(chown, chown_main, _BB_DIR_BIN, _BB_SUID_NEVER))
 USE_CHROOT(APPLET(chroot, chroot_main, _BB_DIR_USR_SBIN, _BB_SUID_NEVER))
 USE_CHVT(APPLET(chvt, chvt_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
+USE_CKSUM(APPLET(cksum, cksum_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_CLEAR(APPLET(clear, clear_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_CMP(APPLET(cmp, cmp_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
 USE_COMM(APPLET(comm, comm_main, _BB_DIR_USR_BIN, _BB_SUID_NEVER))
diff --git a/include/usage.h b/include/usage.h
index d458936ca..3edb0f7ca 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -224,6 +224,11 @@
 #define chvt_full_usage \
         "Changes the foreground virtual terminal to /dev/ttyN"
 
+#define cksum_trivial_usage \
+        "FILES..."
+#define cksum_full_usage \
+        "Calculates the CRC32 checksums of FILES."
+
 #define clear_trivial_usage \
         ""
 #define clear_full_usage \