diff options
Diffstat (limited to 'osframework/source/ImageLib/png/pngpread.c')
| -rw-r--r-- | osframework/source/ImageLib/png/pngpread.c | 1141 |
1 files changed, 1141 insertions, 0 deletions
diff --git a/osframework/source/ImageLib/png/pngpread.c b/osframework/source/ImageLib/png/pngpread.c new file mode 100644 index 0000000..4f98134 --- /dev/null +++ b/osframework/source/ImageLib/png/pngpread.c @@ -0,0 +1,1141 @@ +
+/* pngpread.c - read a png file in push mode
+ *
+ * libpng 1.0.5 - October 15, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
+
+void
+png_process_data(png_structp png_ptr, png_infop info_ptr,
+ png_bytep buffer, png_size_t buffer_size)
+{
+ png_push_restore_buffer(png_ptr, buffer, buffer_size);
+
+ while (png_ptr->buffer_size)
+ {
+ png_process_some_data(png_ptr, info_ptr);
+ }
+}
+
+/* What we do with the incoming data depends on what we were previously
+ * doing before we ran out of data...
+ */
+void
+png_process_some_data(png_structp png_ptr, png_infop info_ptr)
+{
+ switch (png_ptr->process_mode)
+ {
+ case PNG_READ_SIG_MODE:
+ {
+ png_push_read_sig(png_ptr, info_ptr);
+ break;
+ }
+ case PNG_READ_CHUNK_MODE:
+ {
+ png_push_read_chunk(png_ptr, info_ptr);
+ break;
+ }
+ case PNG_READ_IDAT_MODE:
+ {
+ png_push_read_IDAT(png_ptr);
+ break;
+ }
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ case PNG_READ_tEXt_MODE:
+ {
+ png_push_read_tEXt(png_ptr, info_ptr);
+ break;
+ }
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ case PNG_READ_zTXt_MODE:
+ {
+ png_push_read_zTXt(png_ptr, info_ptr);
+ break;
+ }
+#endif
+ case PNG_SKIP_MODE:
+ {
+ png_push_crc_finish(png_ptr);
+ break;
+ }
+ default:
+ {
+ png_ptr->buffer_size = 0;
+ break;
+ }
+ }
+}
+
+/* Read any remaining signature bytes from the stream and compare them with
+ * the correct PNG signature. It is possible that this routine is called
+ * with bytes already read from the signature, either because they have been
+ * checked by the calling application, or because of multiple calls to this
+ * routine.
+ */
+void
+png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
+{
+ png_size_t num_checked = png_ptr->sig_bytes,
+ num_to_check = 8 - num_checked;
+
+ if (png_ptr->buffer_size < num_to_check)
+ {
+ num_to_check = png_ptr->buffer_size;
+ }
+
+ png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
+ num_to_check);
+ png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes+num_to_check);
+
+ if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
+ {
+ if (num_checked < 4 &&
+ png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4))
+ png_error(png_ptr, "Not a PNG file");
+ else
+ png_error(png_ptr, "PNG file corrupted by ASCII conversion");
+ }
+ else
+ {
+ if (png_ptr->sig_bytes >= 8)
+ {
+ png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+ }
+ }
+}
+
+void
+png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
+{
+ /* First we make sure we have enough data for the 4 byte chunk name
+ * and the 4 byte chunk length before proceeding with decoding the
+ * chunk data. To fully decode each of these chunks, we also make
+ * sure we have enough data in the buffer for the 4 byte CRC at the
+ * end of every chunk (except IDAT, which is handled separately).
+ */
+ if (!(png_ptr->flags & PNG_FLAG_HAVE_CHUNK_HEADER))
+ {
+ png_byte chunk_length[4];
+
+ if (png_ptr->buffer_size < 8)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_fill_buffer(png_ptr, chunk_length, 4);
+ png_ptr->push_length = png_get_uint_32(chunk_length);
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+ png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
+ }
+
+ if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
+ }
+ else if (!png_memcmp(png_ptr->chunk_name, png_PLTE, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
+ }
+ else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ /* If we reach an IDAT chunk, this means we have read all of the
+ * header chunks, and we can start reading the image (or if this
+ * is called after the image has been read - we have an error).
+ */
+ if (png_ptr->mode & PNG_HAVE_IDAT)
+ {
+ if (png_ptr->push_length == 0)
+ return;
+
+ if (png_ptr->mode & PNG_AFTER_IDAT)
+ png_error(png_ptr, "Too many IDAT's found");
+ }
+
+ png_ptr->idat_size = png_ptr->push_length;
+ png_ptr->mode |= PNG_HAVE_IDAT;
+ png_ptr->process_mode = PNG_READ_IDAT_MODE;
+ png_push_have_info(png_ptr, info_ptr);
+ png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+ png_ptr->zstream.next_out = png_ptr->row_buf;
+ return;
+ }
+ else if (!png_memcmp(png_ptr->chunk_name, png_IEND, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
+ png_ptr->process_mode = PNG_READ_DONE_MODE;
+ png_push_have_end(png_ptr, info_ptr);
+ }
+#if defined(PNG_READ_gAMA_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_gAMA, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sBIT, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_cHRM, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_sRGB, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tRNS, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_bKGD_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_bKGD, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_hIST, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pHYs, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_oFFs, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_pCAL, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tIME, 4))
+ {
+ if (png_ptr->push_length + 4 > png_ptr->buffer_size)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_tEXt, 4))
+ {
+ png_push_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+ else if (!png_memcmp(png_ptr->chunk_name, png_zTXt, 4))
+ {
+ png_push_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
+ }
+#endif
+ else
+ {
+ png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
+ }
+
+ png_ptr->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER;
+}
+
+void
+png_push_crc_skip(png_structp png_ptr, png_uint_32 skip)
+{
+ png_ptr->process_mode = PNG_SKIP_MODE;
+ png_ptr->skip_length = skip;
+}
+
+void
+png_push_crc_finish(png_structp png_ptr)
+{
+ if (png_ptr->skip_length && png_ptr->save_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->skip_length < (png_uint_32)png_ptr->save_buffer_size)
+ save_size = (png_size_t)png_ptr->skip_length;
+ else
+ save_size = png_ptr->save_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
+
+ png_ptr->skip_length -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->save_buffer_size -= save_size;
+ png_ptr->save_buffer_ptr += save_size;
+ }
+ if (png_ptr->skip_length && png_ptr->current_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->skip_length < (png_uint_32)png_ptr->current_buffer_size)
+ save_size = (png_size_t)png_ptr->skip_length;
+ else
+ save_size = png_ptr->current_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
+
+ png_ptr->skip_length -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->current_buffer_size -= save_size;
+ png_ptr->current_buffer_ptr += save_size;
+ }
+ if (!png_ptr->skip_length)
+ {
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_crc_finish(png_ptr, 0);
+ png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+ }
+}
+
+void
+png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
+{
+ png_bytep ptr;
+
+ ptr = buffer;
+ if (png_ptr->save_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (length < png_ptr->save_buffer_size)
+ save_size = length;
+ else
+ save_size = png_ptr->save_buffer_size;
+
+ png_memcpy(ptr, png_ptr->save_buffer_ptr, save_size);
+ length -= save_size;
+ ptr += save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->save_buffer_size -= save_size;
+ png_ptr->save_buffer_ptr += save_size;
+ }
+ if (length && png_ptr->current_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (length < png_ptr->current_buffer_size)
+ save_size = length;
+ else
+ save_size = png_ptr->current_buffer_size;
+
+ png_memcpy(ptr, png_ptr->current_buffer_ptr, save_size);
+ png_ptr->buffer_size -= save_size;
+ png_ptr->current_buffer_size -= save_size;
+ png_ptr->current_buffer_ptr += save_size;
+ }
+}
+
+void
+png_push_save_buffer(png_structp png_ptr)
+{
+ if (png_ptr->save_buffer_size)
+ {
+ if (png_ptr->save_buffer_ptr != png_ptr->save_buffer)
+ {
+ png_size_t i,istop;
+ png_bytep sp;
+ png_bytep dp;
+
+ istop = png_ptr->save_buffer_size;
+ for (i = 0, sp = png_ptr->save_buffer_ptr, dp = png_ptr->save_buffer;
+ i < istop; i++, sp++, dp++)
+ {
+ *dp = *sp;
+ }
+ }
+ }
+ if (png_ptr->save_buffer_size + png_ptr->current_buffer_size >
+ png_ptr->save_buffer_max)
+ {
+ png_size_t new_max;
+ png_bytep old_buffer;
+
+ new_max = png_ptr->save_buffer_size + png_ptr->current_buffer_size + 256;
+ old_buffer = png_ptr->save_buffer;
+ png_ptr->save_buffer = (png_bytep)png_malloc(png_ptr,
+ (png_uint_32)new_max);
+ png_memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
+ png_free(png_ptr, old_buffer);
+ png_ptr->save_buffer_max = new_max;
+ }
+ if (png_ptr->current_buffer_size)
+ {
+ png_memcpy(png_ptr->save_buffer + png_ptr->save_buffer_size,
+ png_ptr->current_buffer_ptr, png_ptr->current_buffer_size);
+ png_ptr->save_buffer_size += png_ptr->current_buffer_size;
+ png_ptr->current_buffer_size = 0;
+ }
+ png_ptr->save_buffer_ptr = png_ptr->save_buffer;
+ png_ptr->buffer_size = 0;
+}
+
+void
+png_push_restore_buffer(png_structp png_ptr, png_bytep buffer,
+ png_size_t buffer_length)
+{
+ png_ptr->current_buffer = buffer;
+ png_ptr->current_buffer_size = buffer_length;
+ png_ptr->buffer_size = buffer_length + png_ptr->save_buffer_size;
+ png_ptr->current_buffer_ptr = png_ptr->current_buffer;
+}
+
+void
+png_push_read_IDAT(png_structp png_ptr)
+{
+ if (!(png_ptr->flags & PNG_FLAG_HAVE_CHUNK_HEADER))
+ {
+ png_byte chunk_length[4];
+
+ if (png_ptr->buffer_size < 8)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_fill_buffer(png_ptr, chunk_length, 4);
+ png_ptr->push_length = png_get_uint_32(chunk_length);
+
+ png_reset_crc(png_ptr);
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);
+ png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
+
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+ {
+ png_ptr->process_mode = PNG_READ_CHUNK_MODE;
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
+ png_error(png_ptr, "Not enough compressed data");
+ return;
+ }
+
+ png_ptr->idat_size = png_ptr->push_length;
+ }
+ if (png_ptr->idat_size && png_ptr->save_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->idat_size < (png_uint_32)png_ptr->save_buffer_size)
+ {
+ save_size = (png_size_t)png_ptr->idat_size;
+ /* check for overflow */
+ if((png_uint_32)save_size != png_ptr->idat_size)
+ png_error(png_ptr, "save_size overflowed in pngpread");
+ }
+ else
+ save_size = png_ptr->save_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->save_buffer_ptr, save_size);
+ png_process_IDAT_data(png_ptr, png_ptr->save_buffer_ptr, save_size);
+
+ png_ptr->idat_size -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->save_buffer_size -= save_size;
+ png_ptr->save_buffer_ptr += save_size;
+ }
+ if (png_ptr->idat_size && png_ptr->current_buffer_size)
+ {
+ png_size_t save_size;
+
+ if (png_ptr->idat_size < (png_uint_32)png_ptr->current_buffer_size)
+ {
+ save_size = (png_size_t)png_ptr->idat_size;
+ /* check for overflow */
+ if((png_uint_32)save_size != png_ptr->idat_size)
+ png_error(png_ptr, "save_size overflowed in pngpread");
+ }
+ else
+ save_size = png_ptr->current_buffer_size;
+
+ png_calculate_crc(png_ptr, png_ptr->current_buffer_ptr, save_size);
+ png_process_IDAT_data(png_ptr, png_ptr->current_buffer_ptr, save_size);
+
+ png_ptr->idat_size -= save_size;
+ png_ptr->buffer_size -= save_size;
+ png_ptr->current_buffer_size -= save_size;
+ png_ptr->current_buffer_ptr += save_size;
+ }
+ if (!png_ptr->idat_size)
+ {
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_crc_finish(png_ptr, 0);
+ png_ptr->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER;
+ }
+}
+
+void
+png_process_IDAT_data(png_structp png_ptr, png_bytep buffer,
+ png_size_t buffer_length)
+{
+ int ret;
+
+ if ((png_ptr->flags & PNG_FLAG_ZLIB_FINISHED) && buffer_length)
+ png_error(png_ptr, "Extra compression data");
+
+ png_ptr->zstream.next_in = buffer;
+ png_ptr->zstream.avail_in = (uInt)buffer_length;
+ for(;;)
+ {
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+ if (ret == Z_STREAM_END)
+ {
+ if (png_ptr->zstream.avail_in)
+ png_error(png_ptr, "Extra compressed data");
+ if (!(png_ptr->zstream.avail_out))
+ {
+ png_push_process_row(png_ptr);
+ }
+
+ png_ptr->mode |= PNG_AFTER_IDAT;
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
+ break;
+ }
+ else if (ret == Z_BUF_ERROR)
+ break;
+ else if (ret != Z_OK)
+ png_error(png_ptr, "Decompression Error");
+ if (!(png_ptr->zstream.avail_out))
+ {
+ png_push_process_row(png_ptr);
+ png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes;
+ png_ptr->zstream.next_out = png_ptr->row_buf;
+ }
+ else
+ break;
+ }
+}
+
+void
+png_push_process_row(png_structp png_ptr)
+{
+ png_ptr->row_info.color_type = png_ptr->color_type;
+ png_ptr->row_info.width = png_ptr->iwidth;
+ png_ptr->row_info.channels = png_ptr->channels;
+ png_ptr->row_info.bit_depth = png_ptr->bit_depth;
+ png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
+
+ png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
+ (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
+
+ png_read_filter_row(png_ptr, &(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->prev_row + 1,
+ (int)(png_ptr->row_buf[0]));
+
+ png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf,
+ png_ptr->rowbytes + 1);
+
+ if (png_ptr->transformations)
+ png_do_read_transformations(png_ptr);
+
+#if defined(PNG_READ_INTERLACING_SUPPORTED)
+ /* blow up interlaced rows to full size */
+ if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+ {
+ if (png_ptr->pass < 6)
+ png_do_read_interlace(&(png_ptr->row_info),
+ png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations);
+
+ switch (png_ptr->pass)
+ {
+ case 0:
+ {
+ int i;
+ for (i = 0; i < 8 && png_ptr->pass == 0; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ break;
+ }
+ case 1:
+ {
+ int i;
+ for (i = 0; i < 8 && png_ptr->pass == 1; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 2)
+ {
+ for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+ {
+ png_push_have_row(png_ptr, NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ break;
+ }
+ case 2:
+ {
+ int i;
+ for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ for (i = 0; i < 4 && png_ptr->pass == 2; i++)
+ {
+ png_push_have_row(png_ptr, NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ break;
+ }
+ case 3:
+ {
+ int i;
+ for (i = 0; i < 4 && png_ptr->pass == 3; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 4)
+ {
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ break;
+ }
+ case 4:
+ {
+ int i;
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ for (i = 0; i < 2 && png_ptr->pass == 4; i++)
+ {
+ png_push_have_row(png_ptr, NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ break;
+ }
+ case 5:
+ {
+ int i;
+ for (i = 0; i < 2 && png_ptr->pass == 5; i++)
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+ if (png_ptr->pass == 6)
+ {
+ png_push_have_row(png_ptr, NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ break;
+ }
+ case 6:
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ if (png_ptr->pass != 6)
+ break;
+ png_push_have_row(png_ptr, NULL);
+ png_read_push_finish_row(png_ptr);
+ }
+ }
+ }
+ else
+#endif
+ {
+ png_push_have_row(png_ptr, png_ptr->row_buf + 1);
+ png_read_push_finish_row(png_ptr);
+ }
+}
+
+void
+png_read_push_finish_row(png_structp png_ptr)
+{
+ png_ptr->row_number++;
+ if (png_ptr->row_number < png_ptr->num_rows)
+ return;
+
+ if (png_ptr->interlaced)
+ {
+ png_ptr->row_number = 0;
+ png_memset_check(png_ptr, png_ptr->prev_row, 0,
+ png_ptr->rowbytes + 1);
+ do
+ {
+ png_ptr->pass++;
+ if (png_ptr->pass >= 7)
+ break;
+
+ png_ptr->iwidth = (png_ptr->width +
+ png_pass_inc[png_ptr->pass] - 1 -
+ png_pass_start[png_ptr->pass]) /
+ png_pass_inc[png_ptr->pass];
+
+ png_ptr->irowbytes = ((png_ptr->iwidth *
+ png_ptr->pixel_depth + 7) >> 3) + 1;
+
+ if (png_ptr->transformations & PNG_INTERLACE)
+ break;
+
+ png_ptr->num_rows = (png_ptr->height +
+ png_pass_yinc[png_ptr->pass] - 1 -
+ png_pass_ystart[png_ptr->pass]) /
+ png_pass_yinc[png_ptr->pass];
+
+ } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0);
+ }
+}
+
+#if defined(PNG_READ_tEXt_SUPPORTED)
+void
+png_push_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND)
+ {
+ png_error(png_ptr, "Out of place tEXt");
+ /* to quiet some compiler warnings */
+ if(info_ptr == NULL) return;
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ png_ptr->skip_length = 0; /* This may not be necessary */
+
+ if (length > (png_uint_32)65535L) /* Can't hold the entire string in memory */
+ {
+ png_warning(png_ptr, "tEXt chunk too large to fit in memory");
+ png_ptr->skip_length = length - (png_uint_32)65535L;
+ length = (png_uint_32)65535L;
+ }
+#endif
+
+ png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)(length+1));
+ png_ptr->current_text[length] = '\0';
+ png_ptr->current_text_ptr = png_ptr->current_text;
+ png_ptr->current_text_size = (png_size_t)length;
+ png_ptr->current_text_left = (png_size_t)length;
+ png_ptr->process_mode = PNG_READ_tEXt_MODE;
+}
+
+void
+png_push_read_tEXt(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->buffer_size && png_ptr->current_text_left)
+ {
+ png_size_t text_size;
+
+ if (png_ptr->buffer_size < png_ptr->current_text_left)
+ text_size = png_ptr->buffer_size;
+ else
+ text_size = png_ptr->current_text_left;
+ png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+ png_ptr->current_text_left -= text_size;
+ png_ptr->current_text_ptr += text_size;
+ }
+ if (!(png_ptr->current_text_left))
+ {
+ png_textp text_ptr;
+ png_charp text;
+ png_charp key;
+
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_crc_finish(png_ptr);
+
+#if defined(PNG_MAX_MALLOC_64K)
+ if (png_ptr->skip_length)
+ return;
+#endif
+
+ key = png_ptr->current_text;
+ png_ptr->current_text = 0;
+
+ for (text = key; *text; text++)
+ /* empty loop */ ;
+
+ if (text != key + png_ptr->current_text_size)
+ text++;
+
+ text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
+ text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
+ text_ptr->key = key;
+ text_ptr->text = text;
+
+ png_set_text(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, text_ptr);
+ }
+}
+#endif
+
+#if defined(PNG_READ_zTXt_SUPPORTED)
+void
+png_push_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ if (png_ptr->mode == PNG_BEFORE_IHDR || png_ptr->mode & PNG_HAVE_IEND)
+ {
+ png_error(png_ptr, "Out of place zTXt");
+ /* to quiet some compiler warnings */
+ if(info_ptr == NULL) return;
+ }
+
+#ifdef PNG_MAX_MALLOC_64K
+ /* We can't handle zTXt chunks > 64K, since we don't have enough space
+ * to be able to store the uncompressed data. Actually, the threshold
+ * is probably around 32K, but it isn't as definite as 64K is.
+ */
+ if (length > (png_uint_32)65535L)
+ {
+ png_warning(png_ptr, "zTXt chunk too large to fit in memory");
+ png_push_crc_skip(png_ptr, length);
+ return;
+ }
+#endif
+
+ png_ptr->current_text = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)(length+1));
+ png_ptr->current_text[length] = '\0';
+ png_ptr->current_text_ptr = png_ptr->current_text;
+ png_ptr->current_text_size = (png_size_t)length;
+ png_ptr->current_text_left = (png_size_t)length;
+ png_ptr->process_mode = PNG_READ_zTXt_MODE;
+}
+
+void
+png_push_read_zTXt(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->buffer_size && png_ptr->current_text_left)
+ {
+ png_size_t text_size;
+
+ if (png_ptr->buffer_size < (png_uint_32)png_ptr->current_text_left)
+ text_size = png_ptr->buffer_size;
+ else
+ text_size = png_ptr->current_text_left;
+ png_crc_read(png_ptr, (png_bytep)png_ptr->current_text_ptr, text_size);
+ png_ptr->current_text_left -= text_size;
+ png_ptr->current_text_ptr += text_size;
+ }
+ if (!(png_ptr->current_text_left))
+ {
+ png_textp text_ptr;
+ png_charp text;
+ png_charp key;
+ int ret;
+ png_size_t text_size, key_size;
+
+ if (png_ptr->buffer_size < 4)
+ {
+ png_push_save_buffer(png_ptr);
+ return;
+ }
+
+ png_push_crc_finish(png_ptr);
+
+ key = png_ptr->current_text;
+ png_ptr->current_text = 0;
+
+ for (text = key; *text; text++)
+ /* empty loop */ ;
+
+ /* zTXt can't have zero text */
+ if (text == key + png_ptr->current_text_size)
+ {
+ png_free(png_ptr, key);
+ return;
+ }
+
+ text++;
+
+ if (*text != PNG_TEXT_COMPRESSION_zTXt) /* check compression byte */
+ {
+ png_free(png_ptr, key);
+ return;
+ }
+
+ text++;
+
+ png_ptr->zstream.next_in = (png_bytep )text;
+ png_ptr->zstream.avail_in = (uInt)(png_ptr->current_text_size -
+ (text - key));
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+
+ key_size = text - key;
+ text_size = 0;
+ text = NULL;
+ ret = Z_STREAM_END;
+
+ while (png_ptr->zstream.avail_in)
+ {
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
+ if (ret != Z_OK && ret != Z_STREAM_END)
+ {
+ inflateReset(&png_ptr->zstream);
+ png_ptr->zstream.avail_in = 0;
+ png_free(png_ptr, key);
+ png_free(png_ptr, text);
+ return;
+ }
+ if (!(png_ptr->zstream.avail_out) || ret == Z_STREAM_END)
+ {
+ if (text == NULL)
+ {
+ text = (png_charp)png_malloc(png_ptr,
+ (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out +
+ key_size + 1));
+ png_memcpy(text + key_size, png_ptr->zbuf,
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+ png_memcpy(text, key, key_size);
+ text_size = key_size + png_ptr->zbuf_size -
+ png_ptr->zstream.avail_out;
+ *(text + text_size) = '\0';
+ }
+ else
+ {
+ png_charp tmp;
+
+ tmp = text;
+ text = (png_charp)png_malloc(png_ptr, text_size +
+ (png_uint_32)(png_ptr->zbuf_size - png_ptr->zstream.avail_out
+ + 1));
+ png_memcpy(text, tmp, text_size);
+ png_free(png_ptr, tmp);
+ png_memcpy(text + text_size, png_ptr->zbuf,
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out);
+ text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;
+ *(text + text_size) = '\0';
+ }
+ if (ret != Z_STREAM_END)
+ {
+ png_ptr->zstream.next_out = png_ptr->zbuf;
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+ }
+ }
+ else
+ {
+ break;
+ }
+
+ if (ret == Z_STREAM_END)
+ break;
+ }
+
+ inflateReset(&png_ptr->zstream);
+ png_ptr->zstream.avail_in = 0;
+
+ if (ret != Z_STREAM_END)
+ {
+ png_free(png_ptr, key);
+ png_free(png_ptr, text);
+ return;
+ }
+
+ png_free(png_ptr, key);
+ key = text;
+ text += key_size;
+
+ text_ptr = (png_textp)png_malloc(png_ptr, (png_uint_32)sizeof(png_text));
+ text_ptr->compression = PNG_TEXT_COMPRESSION_zTXt;
+ text_ptr->key = key;
+ text_ptr->text = text;
+
+ png_set_text(png_ptr, info_ptr, text_ptr, 1);
+
+ png_free(png_ptr, text_ptr);
+ }
+}
+#endif
+
+/* This function is called when we haven't found a handler for this
+ * chunk. In the future we will have code here that can handle
+ * user-defined callback functions for unknown chunks before they are
+ * ignored or cause an error. If there isn't a problem with the
+ * chunk itself (ie a bad chunk name or a critical chunk), the chunk
+ * is (currently) silently ignored.
+ */
+void
+png_push_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
+{
+ png_check_chunk_name(png_ptr, png_ptr->chunk_name);
+
+ if (!(png_ptr->chunk_name[0] & 0x20))
+ {
+ png_chunk_error(png_ptr, "unknown critical chunk");
+ /* to quiet some compiler warnings */
+ if(info_ptr == NULL) return;
+ }
+
+ png_push_crc_skip(png_ptr, length);
+}
+
+void
+png_push_have_info(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->info_fn != NULL)
+ (*(png_ptr->info_fn))(png_ptr, info_ptr);
+}
+
+void
+png_push_have_end(png_structp png_ptr, png_infop info_ptr)
+{
+ if (png_ptr->end_fn != NULL)
+ (*(png_ptr->end_fn))(png_ptr, info_ptr);
+}
+
+void
+png_push_have_row(png_structp png_ptr, png_bytep row)
+{
+ if (png_ptr->row_fn != NULL)
+ (*(png_ptr->row_fn))(png_ptr, row, png_ptr->row_number,
+ (int)png_ptr->pass);
+}
+
+void
+png_progressive_combine_row (png_structp png_ptr,
+ png_bytep old_row, png_bytep new_row)
+{
+ if (new_row != NULL) /* new_row must == png_ptr->row_buf here. */
+ png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]);
+}
+
+void
+png_set_progressive_read_fn(png_structp png_ptr, png_voidp progressive_ptr,
+ png_progressive_info_ptr info_fn, png_progressive_row_ptr row_fn,
+ png_progressive_end_ptr end_fn)
+{
+ png_ptr->info_fn = info_fn;
+ png_ptr->row_fn = row_fn;
+ png_ptr->end_fn = end_fn;
+
+ png_set_read_fn(png_ptr, progressive_ptr, png_push_fill_buffer);
+}
+
+png_voidp
+png_get_progressive_ptr(png_structp png_ptr)
+{
+ return png_ptr->io_ptr;
+}
+
+#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+
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