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[libpng16] Deflate/inflate was reworked to move common zlib calls into single

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functions [rw]util.c.  A new shared keyword check routine was also added
and the 'zbuf' is no longer allocated on progressive read.  It is now
possible to call png_inflate() incrementally.
This commit is contained in:
John Bowler
2012-03-09 09:15:18 -06:00
committed by Glenn Randers-Pehrson
parent 6038b80277
commit b5d0051dcb
15 changed files with 1579 additions and 1475 deletions
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40
pngwrite.c
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@@ -475,6 +475,8 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
/* Set the zlib control values to defaults; they can be overridden by the
* application after the struct has been created.
*/
png_ptr->zbuffer_size = PNG_ZBUF_SIZE;
png_ptr->zlib_strategy = Z_FILTERED; /* may be overridden if no filters */
png_ptr->zlib_level = Z_DEFAULT_COMPRESSION;
png_ptr->zlib_mem_level = 8;
@@ -784,8 +786,6 @@ png_set_flush(png_structrp png_ptr, int nrows)
void PNGAPI
png_write_flush(png_structrp png_ptr)
{
int wrote_IDAT;
png_debug(1, "in png_write_flush");
if (png_ptr == NULL)
@@ -795,39 +795,7 @@ png_write_flush(png_structrp png_ptr)
if (png_ptr->row_number >= png_ptr->num_rows)
return;
do
{
int ret;
/* Compress the data */
ret = deflate(&png_ptr->zstream, Z_SYNC_FLUSH);
wrote_IDAT = 0;
/* Check for compression errors */
if (ret != Z_OK)
{
if (png_ptr->zstream.msg != NULL)
png_error(png_ptr, png_ptr->zstream.msg);
else
png_error(png_ptr, "zlib error");
}
if (!(png_ptr->zstream.avail_out))
{
/* Write the IDAT and reset the zlib output buffer */
png_write_IDAT(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
wrote_IDAT = 1;
}
} while (wrote_IDAT == 1);
/* If there is any data left to be output, write it into a new IDAT */
if (png_ptr->zbuf_size != png_ptr->zstream.avail_out)
{
/* Write the IDAT and reset the zlib output buffer */
png_write_IDAT(png_ptr, png_ptr->zbuf,
png_ptr->zbuf_size - png_ptr->zstream.avail_out);
}
png_compress_IDAT(png_ptr, NULL, 0, Z_SYNC_FLUSH);
png_ptr->flush_rows = 0;
png_flush(png_ptr);
}
@@ -848,7 +816,7 @@ png_write_destroy(png_structrp png_ptr)
deflateEnd(&png_ptr->zstream);
/* Free our memory. png_free checks NULL for us. */
png_free(png_ptr, png_ptr->zbuf);
png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
png_free(png_ptr, png_ptr->row_buf);
#ifdef PNG_WRITE_FILTER_SUPPORTED
png_free(png_ptr, png_ptr->prev_row);