Dave Jarvis' Repositories

git clone https://repo.autonoma.ca/repo/treetrek.git
git/GitPacks.php
if( $info['offset'] !== 0 ) {
$handle = $this->getHandle( $info['file'] );
- if( $handle ) {
- $result = $this->readPackEntry(
- $handle,
- $info['offset'],
- $len,
- $len
- );
- }
- }
-
- return $result;
- }
-
- public function read( string $sha ): string {
- $info = $this->findPackInfo( $sha );
- $result = '';
-
- if( $info['offset'] !== 0 ) {
- $size = $this->extractPackedSize( $info['file'], $info['offset'] );
- if( $size <= self::MAX_RAM ) {
- $handle = $this->getHandle( $info['file'] );
- if( $handle ) {
- $result = $this->readPackEntry(
- $handle,
- $info['offset'],
- $size
- );
- }
- }
- }
-
- return $result;
- }
-
- public function stream( string $sha, callable $callback ): bool {
- $info = $this->findPackInfo( $sha );
- $result = false;
-
- if( $info['offset'] !== 0 ) {
- $size = $this->extractPackedSize( $info['file'], $info['offset'] );
- $handle = $this->getHandle( $info['file'] );
- if( $handle ) {
- $result = $this->streamPackEntry(
- $handle,
- $info['offset'],
- $size,
- $callback
- );
- }
- }
-
- return $result;
- }
-
- public function getSize( string $sha ): int {
- $info = $this->findPackInfo( $sha );
- $result = 0;
-
- if( $info['offset'] !== 0 ) {
- $result = $this->extractPackedSize( $info['file'], $info['offset'] );
- }
-
- return $result;
- }
-
- private function findPackInfo( string $sha ): array {
- $result = [ 'offset' => 0, 'file' => '' ];
- $binarySha = hex2bin( $sha );
-
- if( strlen( $sha ) === 40 && $binarySha !== false ) {
- if( $this->lastPack !== '' ) {
- $offset = $this->findInIdx( $this->lastPack, $binarySha );
- if( $offset !== 0 ) {
- $result = [
- 'file' => str_replace( '.idx', '.pack', $this->lastPack ),
- 'offset' => $offset
- ];
- }
- }
-
- if( $result['offset'] === 0 ) {
- foreach( $this->packFiles as $indexFile ) {
- if( $indexFile !== $this->lastPack ) {
- $offset = $this->findInIdx( $indexFile, $binarySha );
- if( $offset !== 0 ) {
- $this->lastPack = $indexFile;
- $result = [
- 'file' => str_replace( '.idx', '.pack', $indexFile ),
- 'offset' => $offset
- ];
- break;
- }
- }
- }
- }
- }
-
- return $result;
- }
-
- private function findInIdx( string $indexFile, string $binarySha ): int {
- $handle = $this->getHandle( $indexFile );
- $result = 0;
-
- if( $handle ) {
- if( !isset( $this->fanoutCache[$indexFile] ) ) {
- fseek( $handle, 0 );
- $head = fread( $handle, 8 );
- if( $head === "\377tOc\0\0\0\2" ) {
- $this->fanoutCache[$indexFile] = array_values(
- unpack( 'N*', fread( $handle, 1024 ) )
- );
- }
- }
-
- if( isset( $this->fanoutCache[$indexFile] ) ) {
- $fanout = $this->fanoutCache[$indexFile];
- $byte = ord( $binarySha[0] );
- $start = $byte === 0 ? 0 : $fanout[$byte - 1];
- $end = $fanout[$byte];
-
- if( $end > $start ) {
- $result = $this->binarySearchIdx(
- $indexFile,
- $handle,
- $start,
- $end,
- $binarySha,
- $fanout[255]
- );
- }
- }
- }
-
- return $result;
- }
-
- private function binarySearchIdx(
- string $indexFile,
- $handle,
- int $start,
- int $end,
- string $binarySha,
- int $total
- ): int {
- $key = "$indexFile:$start";
- $count = $end - $start;
- $result = 0;
-
- if( !isset( $this->shaBucketCache[$key] ) ) {
- fseek( $handle, 1032 + ($start * 20) );
- $this->shaBucketCache[$key] = fread( $handle, $count * 20 );
- fseek( $handle, 1032 + ($total * 24) + ($start * 4) );
- $this->offsetBucketCache[$key] = fread( $handle, $count * 4 );
- }
-
- $shaBlock = $this->shaBucketCache[$key];
- $low = 0;
- $high = $count - 1;
- $found = -1;
-
- while( $low <= $high ) {
- $mid = ($low + $high) >> 1;
- $cmp = substr( $shaBlock, $mid * 20, 20 );
-
- if( $cmp < $binarySha ) {
- $low = $mid + 1;
- } elseif( $cmp > $binarySha ) {
- $high = $mid - 1;
- } else {
- $found = $mid;
- break;
- }
- }
-
- if( $found !== -1 ) {
- $packed = substr( $this->offsetBucketCache[$key], $found * 4, 4 );
- $offset = unpack( 'N', $packed )[1];
-
- if( $offset & 0x80000000 ) {
- $pos64 = 1032 + ($total * 28) + (($offset & 0x7FFFFFFF) * 8);
- fseek( $handle, $pos64 );
- $offset = unpack( 'J', fread( $handle, 8 ) )[1];
- }
- $result = (int)$offset;
- }
-
- return $result;
- }
-
- private function readPackEntry(
- $handle,
- int $offset,
- int $size,
- int $cap = 0
- ): string {
- fseek( $handle, $offset );
- $header = $this->readVarInt( $handle );
- $type = ($header['byte'] >> 4) & 7;
-
- return ($type === 6)
- ? $this->handleOfsDelta( $handle, $offset, $size, $cap )
- : (($type === 7)
- ? $this->handleRefDelta( $handle, $size, $cap )
- : $this->decompressToString( $handle, $cap ));
- }
-
- private function streamPackEntry(
- $handle,
- int $offset,
- int $size,
- callable $callback
- ): bool {
- fseek( $handle, $offset );
- $header = $this->readVarInt( $handle );
- $type = ($header['byte'] >> 4) & 7;
-
- return ($type === 6 || $type === 7)
- ? $this->streamDeltaObject( $handle, $offset, $type, $callback )
- : $this->streamDecompression( $handle, $callback );
- }
-
- private function streamDeltaObject(
- $handle,
- int $offset,
- int $type,
- callable $callback
- ): bool {
- fseek( $handle, $offset );
- $this->readVarInt( $handle );
-
- if( $type === 6 ) {
- $byte = ord( fread( $handle, 1 ) );
- $neg = $byte & 127;
- while( $byte & 128 ) {
- $byte = ord( fread( $handle, 1 ) );
- $neg = (($neg + 1) << 7) | ($byte & 127);
- }
- $deltaPos = ftell( $handle );
- $base = '';
- $this->streamPackEntry(
- $handle,
- $offset - $neg,
- 0,
- function( $c ) use ( &$base ) { $base .= $c; }
- );
- fseek( $handle, $deltaPos );
- } else {
- $baseSha = bin2hex( fread( $handle, 20 ) );
- $base = '';
- if( !$this->stream( $baseSha, function( $c ) use ( &$base ) {
- $base .= $c;
- } ) ) {
- return false;
- }
- }
-
- return $this->applyDeltaStream( $handle, $base, $callback );
- }
-
- private function applyDeltaStream(
- $handle,
- string $base,
- callable $callback
- ): bool {
- $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
- if( !$infl ) {
- return false;
- }
-
- $state = 0;
- $buffer = '';
-
- while( !feof( $handle ) ) {
- $chunk = fread( $handle, 8192 );
- if( $chunk === '' ) { break; }
- $data = @inflate_add( $infl, $chunk );
- if( $data === false ) { break; }
- $buffer .= $data;
-
- while( true ) {
- $len = strlen( $buffer );
- if( $len === 0 ) { break; }
-
- if( $state < 2 ) {
- $pos = 0;
- while( $pos < $len && (ord( $buffer[$pos] ) & 128) ) { $pos++; }
- if( $pos === $len && (ord( $buffer[$pos - 1] ) & 128) ) { break; }
- $buffer = substr( $buffer, $pos + 1 );
- $state++;
- continue;
- }
-
- $op = ord( $buffer[0] );
- if( $op & 128 ) {
- $need = 1;
- if( $op & 0x01 ) { $need++; }
- if( $op & 0x02 ) { $need++; }
- if( $op & 0x04 ) { $need++; }
- if( $op & 0x08 ) { $need++; }
- if( $op & 0x10 ) { $need++; }
- if( $op & 0x20 ) { $need++; }
- if( $op & 0x40 ) { $need++; }
-
- if( $len < $need ) { break; }
-
- $off = 0;
- $ln = 0;
- $p = 1;
- if( $op & 0x01 ) { $off |= ord( $buffer[$p++] ); }
- if( $op & 0x02 ) { $off |= ord( $buffer[$p++] ) << 8; }
- if( $op & 0x04 ) { $off |= ord( $buffer[$p++] ) << 16; }
- if( $op & 0x08 ) { $off |= ord( $buffer[$p++] ) << 24; }
- if( $op & 0x10 ) { $ln |= ord( $buffer[$p++] ); }
- if( $op & 0x20 ) { $ln |= ord( $buffer[$p++] ) << 8; }
- if( $op & 0x40 ) { $ln |= ord( $buffer[$p++] ) << 16; }
- if( $ln === 0 ) { $ln = 0x10000; }
-
- $callback( substr( $base, $off, $ln ) );
- $buffer = substr( $buffer, $need );
- } else {
- $ln = $op & 127;
- if( $len < 1 + $ln ) { break; }
- $callback( substr( $buffer, 1, $ln ) );
- $buffer = substr( $buffer, 1 + $ln );
- }
- }
-
- if( inflate_get_status( $infl ) === ZLIB_STREAM_END ) { break; }
- }
- return true;
- }
-
- private function streamDecompression( $handle, callable $callback ): bool {
- $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
- if( !$infl ) {
- return false;
- }
-
- while( !feof( $handle ) ) {
- $chunk = fread( $handle, 8192 );
- if( $chunk === '' ) { break; }
- $data = @inflate_add( $infl, $chunk );
- if( $data !== false && $data !== '' ) {
- $callback( $data );
- }
- if( $data === false ||
- inflate_get_status( $infl ) === ZLIB_STREAM_END ) {
- break;
- }
- }
- return true;
- }
-
- private function decompressToString(
- $handle,
- int $cap = 0
- ): string {
- $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
- $res = '';
-
- if( $infl ) {
- while( !feof( $handle ) ) {
- $chunk = fread( $handle, 8192 );
- if( $chunk === '' ) { break; }
- $data = @inflate_add( $infl, $chunk );
- if( $data !== false ) { $res .= $data; }
- if( $cap > 0 && strlen( $res ) >= $cap ) {
- $res = substr( $res, 0, $cap );
- break;
- }
- if( $data === false ||
- inflate_get_status( $infl ) === ZLIB_STREAM_END ) {
- break;
- }
- }
- }
- return $res;
- }
-
- private function extractPackedSize( string $packPath, int $offset ): int {
- $handle = $this->getHandle( $packPath );
- $size = 0;
-
- if( $handle ) {
- fseek( $handle, $offset );
- $header = $this->readVarInt( $handle );
- $size = $header['value'];
- $type = ($header['byte'] >> 4) & 7;
-
- if( $type === 6 || $type === 7 ) {
- $size = $this->readDeltaTargetSize( $handle, $type );
- }
- }
- return $size;
- }
-
- private function handleOfsDelta(
- $handle,
- int $offset,
- int $size,
- int $cap
- ): string {
- $byte = ord( fread( $handle, 1 ) );
- $neg = $byte & 127;
- while( $byte & 128 ) {
- $byte = ord( fread( $handle, 1 ) );
- $neg = (($neg + 1) << 7) | ($byte & 127);
- }
- $cur = ftell( $handle );
- $base = $offset - $neg;
-
- fseek( $handle, $base );
- $bHead = $this->readVarInt( $handle );
- fseek( $handle, $base );
- $bData = $this->readPackEntry( $handle, $base, $bHead['value'], $cap );
- fseek( $handle, $cur );
-
- $rem = min( self::MAX_READ, max( $size * 2, 1048576 ) );
- $comp = fread( $handle, $rem );
- $delta = @gzuncompress( $comp ) ?: '';
-
- return $this->applyDelta( $bData, $delta, $cap );
- }
-
- private function handleRefDelta( $handle, int $size, int $cap ): string {
- $sha = bin2hex( fread( $handle, 20 ) );
- $bas = $cap > 0 ? $this->peek( $sha, $cap ) : $this->read( $sha );
- $rem = min( self::MAX_READ, max( $size * 2, 1048576 ) );
- $cmp = fread( $handle, $rem );
- $del = @gzuncompress( $cmp ) ?: '';
-
- return $this->applyDelta( $bas, $del, $cap );
- }
-
- private function applyDelta( string $base, string $delta, int $cap ): string {
- $pos = 0;
- $this->readSize( $delta, $pos );
- $this->readSize( $delta, $pos );
-
- $out = '';
- $len = strlen( $delta );
-
- while( $pos < $len ) {
- if( $cap > 0 && strlen( $out ) >= $cap ) { break; }
- $op = ord( $delta[$pos++] );
-
- if( $op & 128 ) {
- $off = 0;
- $ln = 0;
- if( $op & 0x01 ) { $off |= ord( $delta[$pos++] ); }
- if( $op & 0x02 ) { $off |= ord( $delta[$pos++] ) << 8; }
- if( $op & 0x04 ) { $off |= ord( $delta[$pos++] ) << 16; }
- if( $op & 0x08 ) { $off |= ord( $delta[$pos++] ) << 24; }
- if( $op & 0x10 ) { $ln |= ord( $delta[$pos++] ); }
- if( $op & 0x20 ) { $ln |= ord( $delta[$pos++] ) << 8; }
- if( $op & 0x40 ) { $ln |= ord( $delta[$pos++] ) << 16; }
- if( $ln === 0 ) { $ln = 0x10000; }
- $out .= substr( $base, $off, $ln );
- } else {
- $ln = $op & 127;
- $out .= substr( $delta, $pos, $ln );
- $pos += $ln;
- }
- }
- return $out;
- }
-
- private function readVarInt( $handle ): array {
- $byte = ord( fread( $handle, 1 ) );
- $val = $byte & 15;
- $shft = 4;
- $fst = $byte;
-
- while( $byte & 128 ) {
- $byte = ord( fread( $handle, 1 ) );
- $val |= (($byte & 127) << $shft);
- $shft += 7;
- }
- return [ 'value' => $val, 'byte' => $fst ];
- }
-
- private function readDeltaTargetSize( $handle, int $type ): int {
- if( $type === 6 ) {
- $b = ord( fread( $handle, 1 ) );
- while( $b & 128 ) { $b = ord( fread( $handle, 1 ) ); }
- } else {
- fseek( $handle, 20, SEEK_CUR );
- }
-
- $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
- $head = '';
- $try = 0;
-
- if( $infl ) {
- while( !feof( $handle ) && strlen( $head ) < 32 && $try < 64 ) {
- $chunk = fread( $handle, 512 );
- if( $chunk === '' ) { break; }
- $out = @inflate_add( $infl, $chunk, ZLIB_NO_FLUSH );
- if( $out !== false ) { $head .= $out; }
- if( inflate_get_status( $infl ) === ZLIB_STREAM_END ) { break; }
- $try++;
- }
- }
-
- $pos = 0;
- if( strlen( $head ) > 0 ) {
- $this->readSize( $head, $pos );
- return $this->readSize( $head, $pos );
- }
- return 0;
- }
-
- private function readSize( string $data, int &$pos ): int {
- $len = strlen( $data );
- $val = 0;
- $shift = 0;
-
- while( $pos < $len ) {
- $byte = ord( $data[$pos++] );
- $val |= ($byte & 0x7F) << $shift;
-
- if( !($byte & 0x80) ) {
- break;
- }
-
- $shift += 7;
- }
-
- return $val;
- }
-
- private function getHandle( string $path ) {
- if( !isset( $this->fileHandles[$path] ) ) {
- $this->fileHandles[$path] = @fopen( $path, 'rb' );
- }
+
+ if( $handle ) {
+ $result = $this->readPackEntry(
+ $handle,
+ $info['offset'],
+ $len,
+ $len
+ );
+ }
+ }
+
+ return $result;
+ }
+
+ public function read( string $sha ): string {
+ $info = $this->findPackInfo( $sha );
+ $result = '';
+
+ if( $info['offset'] !== 0 ) {
+ $size = $this->extractPackedSize( $info['file'], $info['offset'] );
+
+ if( $size <= self::MAX_RAM ) {
+ $handle = $this->getHandle( $info['file'] );
+
+ if( $handle ) {
+ $result = $this->readPackEntry(
+ $handle,
+ $info['offset'],
+ $size
+ );
+ }
+ }
+ }
+
+ return $result;
+ }
+
+ public function stream( string $sha, callable $callback ): bool {
+ $info = $this->findPackInfo( $sha );
+ $result = false;
+
+ if( $info['offset'] !== 0 ) {
+ $size = $this->extractPackedSize( $info['file'], $info['offset'] );
+ $handle = $this->getHandle( $info['file'] );
+
+ if( $handle ) {
+ $result = $this->streamPackEntry(
+ $handle,
+ $info['offset'],
+ $size,
+ $callback
+ );
+ }
+ }
+
+ return $result;
+ }
+
+ public function getSize( string $sha ): int {
+ $info = $this->findPackInfo( $sha );
+ $result = 0;
+
+ if( $info['offset'] !== 0 ) {
+ $result = $this->extractPackedSize( $info['file'], $info['offset'] );
+ }
+
+ return $result;
+ }
+
+ private function findPackInfo( string $sha ): array {
+ $result = [ 'offset' => 0, 'file' => '' ];
+ $binarySha = hex2bin( $sha );
+
+ if( strlen( $sha ) === 40 && $binarySha !== false ) {
+ if( $this->lastPack !== '' ) {
+ $offset = $this->findInIdx( $this->lastPack, $binarySha );
+
+ if( $offset !== 0 ) {
+ $result = [
+ 'file' => str_replace( '.idx', '.pack', $this->lastPack ),
+ 'offset' => $offset
+ ];
+ }
+ }
+
+ if( $result['offset'] === 0 ) {
+ foreach( $this->packFiles as $indexFile ) {
+ if( $indexFile !== $this->lastPack ) {
+ $offset = $this->findInIdx( $indexFile, $binarySha );
+
+ if( $offset !== 0 ) {
+ $this->lastPack = $indexFile;
+ $result = [
+ 'file' => str_replace( '.idx', '.pack', $indexFile ),
+ 'offset' => $offset
+ ];
+ break;
+ }
+ }
+ }
+ }
+ }
+
+ return $result;
+ }
+
+ private function findInIdx( string $indexFile, string $binarySha ): int {
+ $handle = $this->getHandle( $indexFile );
+ $result = 0;
+
+ if( $handle ) {
+ if( !isset( $this->fanoutCache[$indexFile] ) ) {
+ fseek( $handle, 0 );
+ $head = fread( $handle, 8 );
+
+ if( $head === "\377tOc\0\0\0\2" ) {
+ $this->fanoutCache[$indexFile] = array_values(
+ unpack( 'N*', fread( $handle, 1024 ) )
+ );
+ }
+ }
+
+ if( isset( $this->fanoutCache[$indexFile] ) ) {
+ $fanout = $this->fanoutCache[$indexFile];
+ $byte = ord( $binarySha[0] );
+ $start = $byte === 0 ? 0 : $fanout[$byte - 1];
+ $end = $fanout[$byte];
+
+ if( $end > $start ) {
+ $result = $this->binarySearchIdx(
+ $indexFile,
+ $handle,
+ $start,
+ $end,
+ $binarySha,
+ $fanout[255]
+ );
+ }
+ }
+ }
+
+ return $result;
+ }
+
+ private function binarySearchIdx(
+ string $indexFile,
+ $handle,
+ int $start,
+ int $end,
+ string $binarySha,
+ int $total
+ ): int {
+ $key = "$indexFile:$start";
+ $count = $end - $start;
+ $result = 0;
+
+ if( !isset( $this->shaBucketCache[$key] ) ) {
+ fseek( $handle, 1032 + ($start * 20) );
+ $this->shaBucketCache[$key] = fread( $handle, $count * 20 );
+
+ fseek( $handle, 1032 + ($total * 24) + ($start * 4) );
+ $this->offsetBucketCache[$key] = fread( $handle, $count * 4 );
+ }
+
+ $shaBlock = $this->shaBucketCache[$key];
+ $low = 0;
+ $high = $count - 1;
+ $found = -1;
+
+ while( $low <= $high ) {
+ $mid = ($low + $high) >> 1;
+ $cmp = substr( $shaBlock, $mid * 20, 20 );
+
+ if( $cmp < $binarySha ) {
+ $low = $mid + 1;
+ } elseif( $cmp > $binarySha ) {
+ $high = $mid - 1;
+ } else {
+ $found = $mid;
+ break;
+ }
+ }
+
+ if( $found !== -1 ) {
+ $packed = substr( $this->offsetBucketCache[$key], $found * 4, 4 );
+ $offset = unpack( 'N', $packed )[1];
+
+ if( $offset & 0x80000000 ) {
+ $pos64 = 1032 + ($total * 28) + (($offset & 0x7FFFFFFF) * 8);
+ fseek( $handle, $pos64 );
+ $offset = unpack( 'J', fread( $handle, 8 ) )[1];
+ }
+ $result = (int)$offset;
+ }
+
+ return $result;
+ }
+
+ private function readPackEntry(
+ $handle,
+ int $offset,
+ int $size,
+ int $cap = 0
+ ): string {
+ fseek( $handle, $offset );
+ $header = $this->readVarInt( $handle );
+ $type = ($header['byte'] >> 4) & 7;
+
+ return ($type === 6)
+ ? $this->handleOfsDelta( $handle, $offset, $size, $cap )
+ : (($type === 7)
+ ? $this->handleRefDelta( $handle, $size, $cap )
+ : $this->decompressToString( $handle, $cap ));
+ }
+
+ private function streamPackEntry(
+ $handle,
+ int $offset,
+ int $size,
+ callable $callback
+ ): bool {
+ fseek( $handle, $offset );
+ $header = $this->readVarInt( $handle );
+ $type = ($header['byte'] >> 4) & 7;
+
+ return ($type === 6 || $type === 7)
+ ? $this->streamDeltaObject( $handle, $offset, $type, $callback )
+ : $this->streamDecompression( $handle, $callback );
+ }
+
+ private function streamDeltaObject(
+ $handle,
+ int $offset,
+ int $type,
+ callable $callback
+ ): bool {
+ fseek( $handle, $offset );
+ $this->readVarInt( $handle );
+ $result = false;
+
+ if( $type === 6 ) {
+ $neg = $this->readOffsetDelta( $handle );
+ $deltaPos = ftell( $handle );
+ $base = '';
+
+ $this->streamPackEntry(
+ $handle,
+ $offset - $neg,
+ 0,
+ function( $c ) use ( &$base ) { $base .= $c; }
+ );
+
+ fseek( $handle, $deltaPos );
+ $result = $this->applyDeltaStream( $handle, $base, $callback );
+ } else {
+ $baseSha = bin2hex( fread( $handle, 20 ) );
+ $base = '';
+
+ if( $this->stream( $baseSha, function( $c ) use ( &$base ) {
+ $base .= $c;
+ } ) ) {
+ $result = $this->applyDeltaStream( $handle, $base, $callback );
+ }
+ }
+
+ return $result;
+ }
+
+ private function applyDeltaStream(
+ $handle,
+ string $base,
+ callable $callback
+ ): bool {
+ $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
+ $ok = false;
+
+ if( $infl ) {
+ $state = 0;
+ $buffer = '';
+ $ok = true;
+
+ while( !feof( $handle ) ) {
+ $chunk = fread( $handle, 8192 );
+
+ if( $chunk === '' ) {
+ break;
+ }
+
+ $data = @inflate_add( $infl, $chunk );
+
+ if( $data === false ) {
+ $ok = false;
+ break;
+ }
+
+ $buffer .= $data;
+
+ while( true ) {
+ $len = strlen( $buffer );
+
+ if( $len === 0 ) {
+ break;
+ }
+
+ if( $state < 2 ) {
+ $pos = 0;
+ while( $pos < $len && (ord( $buffer[$pos] ) & 128) ) { $pos++; }
+
+ if( $pos === $len && (ord( $buffer[$pos - 1] ) & 128) ) {
+ break;
+ }
+
+ $buffer = substr( $buffer, $pos + 1 );
+ $state++;
+ continue;
+ }
+
+ $op = ord( $buffer[0] );
+
+ if( $op & 128 ) {
+ $need = $this->getCopyInstructionSize( $op );
+
+ if( $len < 1 + $need ) {
+ break;
+ }
+
+ $info = $this->parseCopyInstruction( $op, $buffer, 1 );
+
+ $callback( substr( $base, $info['off'], $info['len'] ) );
+ $buffer = substr( $buffer, 1 + $need );
+ } else {
+ $ln = $op & 127;
+
+ if( $len < 1 + $ln ) {
+ break;
+ }
+
+ $callback( substr( $buffer, 1, $ln ) );
+ $buffer = substr( $buffer, 1 + $ln );
+ }
+ }
+
+ if( inflate_get_status( $infl ) === ZLIB_STREAM_END ) {
+ break;
+ }
+ }
+ }
+
+ return $ok;
+ }
+
+ private function streamDecompression( $handle, callable $callback ): bool {
+ $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
+
+ if( !$infl ) {
+ return false;
+ }
+
+ while( !feof( $handle ) ) {
+ $chunk = fread( $handle, 8192 );
+
+ if( $chunk === '' ) {
+ break;
+ }
+
+ $data = @inflate_add( $infl, $chunk );
+
+ if( $data !== false && $data !== '' ) {
+ $callback( $data );
+ }
+
+ if( $data === false ||
+ inflate_get_status( $infl ) === ZLIB_STREAM_END ) {
+ break;
+ }
+ }
+
+ return true;
+ }
+
+ private function decompressToString(
+ $handle,
+ int $cap = 0
+ ): string {
+ $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
+ $res = '';
+
+ if( $infl ) {
+ while( !feof( $handle ) ) {
+ $chunk = fread( $handle, 8192 );
+
+ if( $chunk === '' ) {
+ break;
+ }
+
+ $data = @inflate_add( $infl, $chunk );
+
+ if( $data !== false ) {
+ $res .= $data;
+ }
+
+ if( $cap > 0 && strlen( $res ) >= $cap ) {
+ $res = substr( $res, 0, $cap );
+ break;
+ }
+
+ if( $data === false ||
+ inflate_get_status( $infl ) === ZLIB_STREAM_END ) {
+ break;
+ }
+ }
+ }
+
+ return $res;
+ }
+
+ private function extractPackedSize( string $packPath, int $offset ): int {
+ $handle = $this->getHandle( $packPath );
+ $size = 0;
+
+ if( $handle ) {
+ fseek( $handle, $offset );
+ $header = $this->readVarInt( $handle );
+ $size = $header['value'];
+ $type = ($header['byte'] >> 4) & 7;
+
+ if( $type === 6 || $type === 7 ) {
+ $size = $this->readDeltaTargetSize( $handle, $type );
+ }
+ }
+
+ return $size;
+ }
+
+ private function handleOfsDelta(
+ $handle,
+ int $offset,
+ int $size,
+ int $cap
+ ): string {
+ $neg = $this->readOffsetDelta( $handle );
+ $cur = ftell( $handle );
+ $base = $offset - $neg;
+
+ fseek( $handle, $base );
+ $bHead = $this->readVarInt( $handle );
+
+ fseek( $handle, $base );
+ $bData = $this->readPackEntry( $handle, $base, $bHead['value'], $cap );
+
+ fseek( $handle, $cur );
+ $rem = min( self::MAX_READ, max( $size * 2, 1048576 ) );
+ $comp = fread( $handle, $rem );
+ $delta = @gzuncompress( $comp ) ?: '';
+
+ return $this->applyDelta( $bData, $delta, $cap );
+ }
+
+ private function handleRefDelta( $handle, int $size, int $cap ): string {
+ $sha = bin2hex( fread( $handle, 20 ) );
+ $bas = $cap > 0 ? $this->peek( $sha, $cap ) : $this->read( $sha );
+ $rem = min( self::MAX_READ, max( $size * 2, 1048576 ) );
+ $cmp = fread( $handle, $rem );
+ $del = @gzuncompress( $cmp ) ?: '';
+
+ return $this->applyDelta( $bas, $del, $cap );
+ }
+
+ private function applyDelta( string $base, string $delta, int $cap ): string {
+ $pos = 0;
+ $res = $this->readDeltaSize( $delta, $pos );
+ $pos += $res['used'];
+ $res = $this->readDeltaSize( $delta, $pos );
+ $pos += $res['used'];
+
+ $out = '';
+ $len = strlen( $delta );
+
+ while( $pos < $len ) {
+ if( $cap > 0 && strlen( $out ) >= $cap ) {
+ break;
+ }
+
+ $op = ord( $delta[$pos++] );
+
+ if( $op & 128 ) {
+ $info = $this->parseCopyInstruction( $op, $delta, $pos );
+ $out .= substr( $base, $info['off'], $info['len'] );
+ $pos += $info['used'];
+ } else {
+ $ln = $op & 127;
+ $out .= substr( $delta, $pos, $ln );
+ $pos += $ln;
+ }
+ }
+
+ return $out;
+ }
+
+ private function parseCopyInstruction(
+ int $op,
+ string $data,
+ int $pos
+ ): array {
+ $off = 0;
+ $len = 0;
+ $ptr = $pos;
+
+ if( $op & 0x01 ) { $off |= ord( $data[$ptr++] ); }
+ if( $op & 0x02 ) { $off |= ord( $data[$ptr++] ) << 8; }
+ if( $op & 0x04 ) { $off |= ord( $data[$ptr++] ) << 16; }
+ if( $op & 0x08 ) { $off |= ord( $data[$ptr++] ) << 24; }
+
+ if( $op & 0x10 ) { $len |= ord( $data[$ptr++] ); }
+ if( $op & 0x20 ) { $len |= ord( $data[$ptr++] ) << 8; }
+ if( $op & 0x40 ) { $len |= ord( $data[$ptr++] ) << 16; }
+
+ return [
+ 'off' => $off,
+ 'len' => $len ?: 0x10000,
+ 'used' => $ptr - $pos
+ ];
+ }
+
+ private function getCopyInstructionSize( int $op ): int {
+ $c = $op & 0x7F;
+ $c = $c - (( $c >> 1 ) & 0x55);
+ $c = (( $c >> 2 ) & 0x33) + ( $c & 0x33 );
+ $c = (( $c >> 4 ) + $c) & 0x0F;
+
+ return $c;
+ }
+
+ private function readVarInt( $handle ): array {
+ $byte = ord( fread( $handle, 1 ) );
+ $val = $byte & 15;
+ $shft = 4;
+ $fst = $byte;
+
+ while( $byte & 128 ) {
+ $byte = ord( fread( $handle, 1 ) );
+ $val |= (($byte & 127) << $shft);
+ $shft += 7;
+ }
+
+ return [ 'value' => $val, 'byte' => $fst ];
+ }
+
+ private function readOffsetDelta( $handle ): int {
+ $byte = ord( fread( $handle, 1 ) );
+ $neg = $byte & 127;
+
+ while( $byte & 128 ) {
+ $byte = ord( fread( $handle, 1 ) );
+ $neg = (($neg + 1) << 7) | ($byte & 127);
+ }
+
+ return $neg;
+ }
+
+ private function readDeltaTargetSize( $handle, int $type ): int {
+ if( $type === 6 ) {
+ $b = ord( fread( $handle, 1 ) );
+ while( $b & 128 ) { $b = ord( fread( $handle, 1 ) ); }
+ } else {
+ fseek( $handle, 20, SEEK_CUR );
+ }
+
+ $infl = inflate_init( ZLIB_ENCODING_DEFLATE );
+ $head = '';
+ $try = 0;
+
+ if( $infl ) {
+ while( !feof( $handle ) && strlen( $head ) < 32 && $try < 64 ) {
+ $chunk = fread( $handle, 512 );
+
+ if( $chunk === '' ) {
+ break;
+ }
+
+ $out = @inflate_add( $infl, $chunk, ZLIB_NO_FLUSH );
+
+ if( $out !== false ) {
+ $head .= $out;
+ }
+
+ if( inflate_get_status( $infl ) === ZLIB_STREAM_END ) {
+ break;
+ }
+
+ $try++;
+ }
+ }
+
+ $pos = 0;
+
+ if( strlen( $head ) > 0 ) {
+ $res = $this->readDeltaSize( $head, $pos );
+ $pos += $res['used'];
+ $res = $this->readDeltaSize( $head, $pos );
+
+ return $res['val'];
+ }
+
+ return 0;
+ }
+
+ private function readDeltaSize( string $data, int $pos ): array {
+ $len = strlen( $data );
+ $val = 0;
+ $shift = 0;
+ $start = $pos;
+
+ while( $pos < $len ) {
+ $byte = ord( $data[$pos++] );
+ $val |= ($byte & 0x7F) << $shift;
+
+ if( !($byte & 0x80) ) {
+ break;
+ }
+
+ $shift += 7;
+ }
+
+ return [ 'val' => $val, 'used' => $pos - $start ];
+ }
+
+ private function getHandle( string $path ) {
+ if( !isset( $this->fileHandles[$path] ) ) {
+ $this->fileHandles[$path] = @fopen( $path, 'rb' );
+ }
+
return $this->fileHandles[$path];
}

Reformats code, speeds up algorithm

Author Dave Jarvis <email>
Date 2026-02-16 17:41:57 GMT-0800
Commit 54de68601329e8b44f6a2a780d278a0ab191d5d2
Parent 01bdff3
Delta 632 lines added, 536 lines removed, 96-line increase