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(libT) calculate a piece's checksum on the stack, rather than the heap

This commit is contained in:
Charles Kerr 2008-09-06 13:25:21 +00:00
parent 77fdc04c0e
commit 55a01eea2c
1 changed files with 21 additions and 22 deletions
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43
libtransmission/inout.c
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@ -19,6 +19,8 @@
#include <sys/stat.h>
#include <unistd.h>
#include <openssl/sha.h>
#include "transmission.h"
#include "crypto.h"
#include "fdlimit.h"
@ -226,36 +228,33 @@ recalculateHash( const tr_torrent * tor,
tr_piece_index_t pieceIndex,
uint8_t * setme )
{
static uint8_t * buf = NULL;
static int buflen = 0;
static tr_lock * lock = NULL;
int n;
tr_errno err;
/* only check one block at a time to prevent disk thrashing.
* this also lets us reuse the same buffer each time. */
if( lock == NULL )
lock = tr_lockNew( );
tr_lockLock( lock );
size_t bytesLeft;
size_t n;
uint32_t offset = 0;
tr_errno err = 0;
SHA_CTX sha;
assert( tor );
assert( setme );
assert( pieceIndex < tor->info.pieceCount );
n = tr_torPieceCountBytes( tor, pieceIndex );
SHA1_Init( &sha );
n = bytesLeft = tr_torPieceCountBytes( tor, pieceIndex );
if( buflen < n ) {
buflen = n;
buf = tr_renew( uint8_t, buf, buflen );
while( bytesLeft )
{
uint8_t buf[2048];
const int len = MIN( bytesLeft, sizeof( buf ) );
if(( err = tr_ioRead( tor, pieceIndex, offset, len, buf )))
break;
SHA1_Update( &sha, buf, len );
offset += len;
bytesLeft -= len;
}
err = tr_ioRead( tor, pieceIndex, 0, n, buf );
if( !err )
tr_sha1( setme, buf, n, NULL );
tr_lockUnlock( lock );
if( !err )
SHA1_Final( setme, &sha );
return err;
}