- Updated the address for the FSF in the opening comment.

[rsync/rsync.git] / checksum.c

diff --git a/checksum.c b/checksum.c
index e3b8719..a86904b 100644 (file)
--- a/checksum.c
+++ b/checksum.c
@@ -1,21 +1,24 @@
 /*
-   Copyright (C) Andrew Tridgell 1996
-   Copyright (C) Paul Mackerras 1996
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 2 of the License, or
-   (at your option) any later version.
-
-   This program is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU General Public License for more details.
-
-   You should have received a copy of the GNU General Public License
-   along with this program; if not, write to the Free Software
-   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
+ * Routines to support checksumming of bytes.
+ *
+ * Copyright (C) 1996 Andrew Tridgell
+ * Copyright (C) 1996 Paul Mackerras
+ * Copyright (C) 2004, 2005 Wayne Davison
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
 
 #include "rsync.h"
 
@@ -30,9 +33,9 @@ extern int protocol_version;
   a simple 32 bit checksum that can be upadted from either end
   (inspired by Mark Adler's Adler-32 checksum)
   */
-uint32 get_checksum1(char *buf1,int len)
+uint32 get_checksum1(char *buf1, int32 len)
 {
-    int i;
+    int32 i;
     uint32 s1, s2;
     schar *buf = (schar *)buf1;
 
@@ -49,18 +52,20 @@ uint32 get_checksum1(char *buf1,int len)
 }
 
 
-void get_checksum2(char *buf,int len,char *sum)
+void get_checksum2(char *buf, int32 len, char *sum)
 {
-       int i;
+       int32 i;
        static char *buf1;
-       static int len1;
+       static int32 len1;
        struct mdfour m;
 
        if (len > len1) {
-               if (buf1) free(buf1);
+               if (buf1)
+                       free(buf1);
                buf1 = new_array(char, len+4);
                len1 = len;
-               if (!buf1) out_of_memory("get_checksum2");
+               if (!buf1)
+                       out_of_memory("get_checksum2");
        }
 
        mdfour_begin(&m);
@@ -102,7 +107,7 @@ void file_checksum(char *fname,char *sum,OFF_T size)
        if (fd == -1)
                return;
 
-       buf = map_file(fd, size, CSUM_CHUNK * 2048, 0);
+       buf = map_file(fd, size, MAX_MAP_SIZE, CSUM_CHUNK);
 
        mdfour_begin(&m);
 
@@ -125,7 +130,7 @@ void file_checksum(char *fname,char *sum,OFF_T size)
 }
 
 
-static int sumresidue;
+static int32 sumresidue;
 static char sumrbuf[CSUM_CHUNK];
 static struct mdfour md;
 
@@ -146,41 +151,37 @@ void sum_init(int seed)
  * @todo Perhaps get rid of md and just pass in the address each time.
  * Very slightly clearer and slower.
  **/
-void sum_update(char *p, int len)
+void sum_update(char *p, int32 len)
 {
-       int i;
        if (len + sumresidue < CSUM_CHUNK) {
-               memcpy(sumrbuf+sumresidue, p, len);
+               memcpy(sumrbuf + sumresidue, p, len);
                sumresidue += len;
                return;
        }
 
        if (sumresidue) {
-               i = MIN(CSUM_CHUNK-sumresidue,len);
-               memcpy(sumrbuf+sumresidue,p,i);
-               mdfour_update(&md, (uchar *)sumrbuf, (i+sumresidue));
+               int32 i = CSUM_CHUNK - sumresidue;
+               memcpy(sumrbuf + sumresidue, p, i);
+               mdfour_update(&md, (uchar *)sumrbuf, CSUM_CHUNK);
                len -= i;
                p += i;
        }
 
-       for(i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK) {
-               memcpy(sumrbuf,p+i,CSUM_CHUNK);
-               mdfour_update(&md, (uchar *)sumrbuf, CSUM_CHUNK);
+       while (len >= CSUM_CHUNK) {
+               mdfour_update(&md, (uchar *)p, CSUM_CHUNK);
+               len -= CSUM_CHUNK;
+               p += CSUM_CHUNK;
        }
 
-       if (len - i > 0) {
-               sumresidue = len-i;
-               memcpy(sumrbuf,p+i,sumresidue);
-       } else {
-               sumresidue = 0;
-       }
+       sumresidue = len;
+       if (sumresidue)
+               memcpy(sumrbuf, p, sumresidue);
 }
 
 void sum_end(char *sum)
 {
-       if (sumresidue || protocol_version >= 27) {
+       if (sumresidue || protocol_version >= 27)
                mdfour_update(&md, (uchar *)sumrbuf, sumresidue);
-       }
 
        mdfour_result(&md, (uchar *)sum);
 }