| //======================================================================== |
| // |
| // FlateStream.cc |
| // |
| // Copyright (C) 2005, Jeff Muizelaar <jeff@infidigm.net> |
| // Copyright (C) 2010, Albert Astals Cid <aacid@kde.org> |
| // |
| // This file is under the GPLv2 or later license |
| // |
| //======================================================================== |
| #include "FlateStream.h" |
| FlateStream::FlateStream(Stream *strA, int predictor, int columns, int colors, int bits) : |
| FilterStream(strA) |
| { |
| if (predictor != 1) { |
| pred = new StreamPredictor(this, predictor, columns, colors, bits); |
| } else { |
| pred = NULL; |
| } |
| out_pos = 0; |
| memset(&d_stream, 0, sizeof(d_stream)); |
| inflateInit(&d_stream); |
| } |
| |
| FlateStream::~FlateStream() { |
| inflateEnd(&d_stream); |
| delete pred; |
| delete str; |
| } |
| |
| void FlateStream::reset() { |
| //FIXME: what are the semantics of reset? |
| //i.e. how much intialization has to happen in the constructor? |
| |
| /* reinitialize zlib */ |
| inflateEnd(&d_stream); |
| memset(&d_stream, 0, sizeof(d_stream)); |
| inflateInit(&d_stream); |
| |
| str->reset(); |
| d_stream.avail_in = 0; |
| status = Z_OK; |
| out_pos = 0; |
| out_buf_len = 0; |
| } |
| |
| int FlateStream::getRawChar() { |
| return doGetRawChar(); |
| } |
| |
| void FlateStream::getRawChars(int nChars, int *buffer) { |
| for (int i = 0; i < nChars; ++i) |
| buffer[i] = doGetRawChar(); |
| } |
| |
| int FlateStream::getChar() { |
| if (pred) |
| return pred->getChar(); |
| else |
| return getRawChar(); |
| } |
| |
| int FlateStream::lookChar() { |
| if (pred) |
| return pred->lookChar(); |
| |
| if (fill_buffer()) |
| return EOF; |
| |
| return out_buf[out_pos]; |
| } |
| |
| int FlateStream::fill_buffer() { |
| /* only fill the buffer if it has all been used */ |
| if (out_pos >= out_buf_len) { |
| /* check if the flatestream has been exhausted */ |
| if (status == Z_STREAM_END) { |
| return -1; |
| } |
| |
| /* set to the begining of out_buf */ |
| d_stream.avail_out = sizeof(out_buf); |
| d_stream.next_out = out_buf; |
| out_pos = 0; |
| |
| while (1) { |
| /* buffer is empty so we need to fill it */ |
| if (d_stream.avail_in == 0) { |
| int c; |
| /* read from the source stream */ |
| while (d_stream.avail_in < sizeof(in_buf) && (c = str->getChar()) != EOF) { |
| in_buf[d_stream.avail_in++] = c; |
| } |
| d_stream.next_in = in_buf; |
| } |
| |
| /* keep decompressing until we can't anymore */ |
| if (d_stream.avail_out == 0 || d_stream.avail_in == 0 || (status != Z_OK && status != Z_BUF_ERROR)) |
| break; |
| status = inflate(&d_stream, Z_SYNC_FLUSH); |
| } |
| |
| out_buf_len = sizeof(out_buf) - d_stream.avail_out; |
| if (status != Z_OK && status != Z_STREAM_END) |
| return -1; |
| if (!out_buf_len) |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| GooString *FlateStream::getPSFilter(int psLevel, char *indent) { |
| GooString *s; |
| |
| if (psLevel < 3 || pred) { |
| return NULL; |
| } |
| if (!(s = str->getPSFilter(psLevel, indent))) { |
| return NULL; |
| } |
| s->append(indent)->append("<< >> /FlateDecode filter\n"); |
| return s; |
| } |
| |
| GBool FlateStream::isBinary(GBool last) { |
| return str->isBinary(gTrue); |
| } |