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ip2region_private
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update btree search

This commit is contained in:
dongyado 2016-07-07 09:21:38 +08:00
parent 63cd3fa085
commit a2e3bdb13e
1 changed files with 99 additions and 4 deletions
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103
binding/nodejs/ip2region.js
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@ -26,10 +26,6 @@ var totalHeaderLength = 4096;
* */ * */
ip2region.binarySearch = function(ip) ip2region.binarySearch = function(ip)
{ {
if( typeof(ip) == 'string' )
ip = ip2long(ip);
// search
var low = 0; var low = 0;
var mid = 0; var mid = 0;
var high = totalBlocks; var high = totalBlocks;
@ -39,6 +35,8 @@ ip2region.binarySearch = function(ip)
var eip = 0; var eip = 0;
var indexBuffer = new Buffer(12); var indexBuffer = new Buffer(12);
if( typeof(ip) == 'string' ) ip = ip2long(ip);
// binary search // binary search
while( low <= high ) { while( low <= high ) {
mid = ((low + high) >> 1); mid = ((low + high) >> 1);
@ -78,11 +76,108 @@ ip2region.binarySearch = function(ip)
} }
var headerSip = null;
var headerPtr = 0;
var headerLen = 0;
/** /**
* btree search * btree search
* */ * */
ip2region.btreeSearch = function(ip) ip2region.btreeSearch = function(ip)
{ {
var indexBlockBuffer = new Buffer(indexBlockLength);
var headerIndexBuffer = new Buffer(totalHeaderLength);
if( typeof(ip) == 'string' ) ip = ip2long($ip);
var i = 0;
// header index handler
if (headerSip == null) {
fs.readSync(ip2region.db_fd, headerIndexBuffer, 0, totalHeaderLength,8);
headerSip = [];
headerPtr = [];
var startIp = 0;
var dataPtr = 0;
for ( i = 0; i < totalHeaderLength; i += 8) {
startIp = getLong(headerIndexBuffer, $i);
dataPtr = getLong(headerIndexBuffer, $i + 4);
if ( dataPtr == 0) break;
headerSip.array_push(startIp);
headerPtr.array_push(dataPtr);
headerLen++; // header index size count
}
}
// first search (in header index)
var low = 0;
var mid = 0;
var high = headerLen;
var sptr = 0;
var eptr = 0;
while(low <= high) {
mid = ((low + hign) >> 1);
if (ip == headerIndex[mid]) {
if ( m > 0) {
sptr = headerPtr[mid - 1];
eptr = headerPtr[mid];
} else {
sptr = headerPtr[mid];
eptr = headerPtr[mid + 1];
}
break;
}
if ( ip < headerSip[mid]) {
if (mid == 0) {
sptr = headerPtr[mid];
eptr = headerPtr[mid + 1];
break;
} else if ( ip > headerPtr[mid - 1]) {
sptr = headerPtr[mid - 1];
eptr = headerPtr[mid];
break;
}
low = mid - 1;
} else {
if ( mid = headerLen - 1) {
sptr = headerPtr[mid - 1];
eptr = headerPtr[mid];
break;
} else if ( ip <= headerSip[mid + 1]) {
sptr = headerPtr[mid];
eptr = headerPtr[mid + 1];
break;
}
low = mid + 1;
}
}
// match nothing
if (sptr == 0) return null;
// second search (in index)
var blockLen = eptr - sptr;
var blockBuffer = new Buffer(blockLen);
fs.readSync(ip2region.db_fd, blockBuffer, 0, blockLen + indexBlockLength, sptr);
low = 0;
high = blockLen / indexBlockLength;
var p = 0;
var sip = 0;
var eip = 0;
while(low <= high) {
mid = ((low + high) >> 1);
p = mid * indexBlockLength;
}
return ip2long(ip); return ip2long(ip);
} }