NPT_Result
NPT_StreamToStreamCopy(NPT_InputStream& from,
NPT_OutputStream& to,
NPT_Position offset /* = 0 */,
NPT_Size size /* = 0, 0 means the entire stream */)
{
// seek into the input if required
if (offset) {
NPT_CHECK(from.Seek(offset));
}
// allocate a buffer for the transfer
NPT_Size bytes_transfered = 0;
NPT_Byte* buffer = new NPT_Byte[NPT_STREAM_COPY_BUFFER_SIZE];
NPT_Result result = NPT_SUCCESS;
if (buffer == NULL) return NPT_ERROR_OUT_OF_MEMORY;
// copy until an error occurs or the end of stream is reached
for (;;) {
// read some data
NPT_Size bytes_to_read = NPT_STREAM_COPY_BUFFER_SIZE;
NPT_Size bytes_read = 0;
if (size) {
// a max size was specified
if (bytes_to_read > size-bytes_transfered) {
bytes_to_read = size-bytes_transfered;
}
}
result = from.Read(buffer, bytes_to_read, &bytes_read);
if (NPT_FAILED(result)) {
if (result == NPT_ERROR_EOS) result = NPT_SUCCESS;
break;
}
if (bytes_read == 0) continue;
// write the data
result = to.WriteFully(buffer, bytes_read);
if (NPT_FAILED(result)) break;
// update the counts
if (size) {
bytes_transfered += bytes_read;
if (bytes_transfered >= size) break;
}
}
// free the buffer and return
delete[] buffer;
return result;
}
/*----------------------------------------------------------------------
| NPT_ZipFile::Parse
+---------------------------------------------------------------------*/
NPT_Result
NPT_ZipFile::Parse(NPT_InputStream& stream, NPT_ZipFile*& file)
{
// defautl return value
file = NULL;
// check that we know the size of the stream
NPT_LargeSize stream_size = 0;
NPT_Result result = stream.GetSize(stream_size);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("cannot get stream size (%d)", result);
return result;
}
if (stream_size < 22) {
NPT_LOG_WARNING("input stream too short");
return NPT_ERROR_INVALID_FORMAT;
}
// seek to the most likely start of the end of central directory record
unsigned int max_eocdr_size = 22+65536;
if (max_eocdr_size > stream_size) {
max_eocdr_size = (unsigned int)stream_size;
}
unsigned char eocdr[22];
bool record_found = false;
NPT_Position position = 0;
for (unsigned int i=0; i<max_eocdr_size; i++) {
position = stream_size-22-i;
result = stream.Seek(position);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("seek failed (%d)", result);
return result;
}
result = stream.ReadFully(eocdr, 22);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("read failed (%d)", result);
return result;
}
NPT_UInt32 signature = NPT_BytesToInt32Le(eocdr);
if (signature == NPT_ZIP_END_OF_CENTRAL_DIRECTORY_SIGNATURE) {
record_found = true;
break;
}
}
if (!record_found) {
NPT_LOG_WARNING("eocd record not found at end of stream");
return NPT_ERROR_INVALID_FORMAT;
}
// parse the eocdr
NPT_UInt32 this_disk = NPT_BytesToInt16Le(&eocdr[ 4]);
NPT_UInt32 start_disk = NPT_BytesToInt16Le(&eocdr[ 6]);
NPT_UInt64 this_disk_entry_count = NPT_BytesToInt16Le(&eocdr[ 8]);
NPT_UInt64 total_entry_count = NPT_BytesToInt16Le(&eocdr[10]);
NPT_UInt64 central_directory_size = NPT_BytesToInt32Le(&eocdr[12]);
NPT_Position central_directory_offset = NPT_BytesToInt32Le(&eocdr[16]);
// format check
if (this_disk != 0 || start_disk != 0) {
return NPT_ERROR_NOT_SUPPORTED;
}
if (this_disk_entry_count != total_entry_count) {
return NPT_ERROR_NOT_SUPPORTED;
}
// check if this is a zip64 file
if (central_directory_offset == 0xFFFFFFFF) {
unsigned char zip64_locator[20];
result = stream.Seek(position-20);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("seek failed (%d)", result);
return result;
}
result = stream.ReadFully(zip64_locator, 20);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("read failed (%d)", result);
return result;
}
NPT_UInt32 signature = NPT_BytesToInt32Le(&zip64_locator[0]);
if (signature != NPT_ZIP64_END_OF_CENTRAL_DIRECTORY_LOCATOR_SIGNATURE) {
NPT_LOG_WARNING("zip64 directory locator signature not found");
return NPT_ERROR_INVALID_FORMAT;
}
NPT_UInt32 zip64_disk_start = NPT_BytesToInt32Le(&zip64_locator[ 4]);
NPT_UInt64 zip64_directory_offset = NPT_BytesToInt64Le(&zip64_locator[ 8]);
NPT_UInt32 zip64_disk_count = NPT_BytesToInt32Le(&zip64_locator[16]);
// format check
if (zip64_disk_start != 0 || zip64_disk_count != 1) {
return NPT_ERROR_NOT_SUPPORTED;
}
// size check
if (zip64_directory_offset > stream_size) {
NPT_LOG_WARNING("zip64 directory offset too large");
return NPT_ERROR_INVALID_FORMAT;
}
// load and parse the eocdr64
unsigned char eocdr64[56];
result = stream.Seek(zip64_directory_offset);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("seek failed (%d)", result);
return result;
}
result = stream.ReadFully(eocdr64, 56);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("read failed (%d)", result);
return result;
}
signature = NPT_BytesToInt32Le(&eocdr64[0]);
if (signature != NPT_ZIP64_END_OF_CENTRAL_DIRECTORY_SIGNATURE) {
NPT_LOG_WARNING("zip64 directory signature not found");
return NPT_ERROR_INVALID_FORMAT;
}
this_disk = NPT_BytesToInt32Le(&eocdr64[16]);
start_disk = NPT_BytesToInt32Le(&eocdr64[20]);
this_disk_entry_count = NPT_BytesToInt64Le(&eocdr64[24]);
total_entry_count = NPT_BytesToInt64Le(&eocdr64[32]);
central_directory_size = NPT_BytesToInt64Le(&eocdr64[40]);
central_directory_offset = NPT_BytesToInt64Le(&eocdr64[48]);
}
// format check
if (this_disk != 0 || start_disk != 0) {
return NPT_ERROR_NOT_SUPPORTED;
}
if (this_disk_entry_count != total_entry_count) {
return NPT_ERROR_NOT_SUPPORTED;
}
// check that the size looks reasonable
if (central_directory_size > NPT_ZIP_MAX_DIRECTORY_SIZE) {
NPT_LOG_WARNING("central directory larger than max supported");
return NPT_ERROR_OUT_OF_RANGE;
}
if (total_entry_count > NPT_ZIP_MAX_ENTRY_COUNT) {
NPT_LOG_WARNING("central directory larger than max supported");
return NPT_ERROR_OUT_OF_RANGE;
}
// read the central directory
NPT_DataBuffer central_directory_buffer;
result = central_directory_buffer.SetDataSize((NPT_Size)central_directory_size);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("central directory too large (%lld)", central_directory_size);
return result;
}
result = stream.Seek(central_directory_offset);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("seek failed (%d)", result);
return result;
}
result = stream.ReadFully(central_directory_buffer.UseData(), (NPT_Size)central_directory_size);
if (NPT_FAILED(result)) {
NPT_LOG_WARNING_1("failed to read central directory (%d)", result);
return result;
}
// create a new file object
file = new NPT_ZipFile();
file->m_Entries.Reserve((NPT_Cardinal)total_entry_count);
// parse all entries
const unsigned char* buffer = (const unsigned char*)central_directory_buffer.GetData();
for (unsigned int i=0; i<total_entry_count; i++) {
NPT_UInt32 signature = NPT_BytesToInt32Le(buffer);
if (signature != NPT_ZIP_CENTRAL_FILE_HEADER_SIGNATURE) {
NPT_LOG_WARNING("unexpected signature in central directory");
break;
}
NPT_ZipFile::Entry entry(buffer);
if (entry.m_DirectoryEntrySize > central_directory_size) {
NPT_LOG_WARNING_1("entry size too large (%d)", entry.m_DirectoryEntrySize);
break;
}
file->GetEntries().Add(entry);
central_directory_size -= entry.m_DirectoryEntrySize;
buffer += entry.m_DirectoryEntrySize;
}
return NPT_SUCCESS;
}
