casa-mp-base
Public
Commits
David Strubbe authored 374ac29b5fe
| 1 + | # HG changeset patch |
| 2 + | # User Vin Shelton <acs@xemacs.org> |
| 3 + | # Date 1323317837 18000 |
| 4 + | # Node ID 51ced9b8fb63e4be59ea611b58128c400e3df987 |
| 5 + | # Parent 032a91928d47b36ae3dd98885767d9e0202892f7 |
| 6 + | Clean up PNG handling. Fix crash in issue570. |
| 7 + | |
| 8 + | diff -r 032a91928d47b36ae3dd98885767d9e0202892f7 -r 51ced9b8fb63e4be59ea611b58128c400e3df987 src/glyphs-eimage.c |
| 9 + | --- a/src/glyphs-eimage.c Sat Dec 03 20:04:12 2011 -0500 |
| 10 + | +++ b/src/glyphs-eimage.c Wed Dec 07 23:17:17 2011 -0500 |
| 11 + | |
| 12 + | png_read_info (png_ptr, info_ptr); |
| 13 + | |
| 14 + | { |
| 15 + | - int y; |
| 16 + | + int y, padding; |
| 17 + | unsigned char **row_pointers; |
| 18 + | height = info_ptr->height; |
| 19 + | width = info_ptr->width; |
| 20 + | |
| 21 + | - /* Wow, allocate all the memory. Truly, exciting. */ |
| 22 + | - unwind.eimage = xnew_array_and_zero (unsigned char, width * height * 3); |
| 23 + | + /* Wow, allocate all the memory. Truly, exciting. |
| 24 + | + Well, yes, there's excitement to be had. It turns out that libpng |
| 25 + | + strips in place, so the last row overruns the buffer if depth is 16 |
| 26 + | + or there's an alpha channel. This is a crash on Linux. So we need |
| 27 + | + to add padding. |
| 28 + | + The worst case is reducing 8 bytes (16-bit RGBA) to 3 (8-bit RGB). */ |
| 29 + | + |
| 30 + | + padding = 5 * width; |
| 31 + | + unwind.eimage = xnew_array_and_zero (unsigned char, |
| 32 + | + width * height * 3 + padding); |
| 33 + | + |
| 34 + | /* libpng expects that the image buffer passed in contains a |
| 35 + | picture to draw on top of if the png has any transparencies. |
| 36 + | This could be a good place to pass that in... */ |
| 37 + | |
| 38 + | if (info_ptr->color_type == PNG_COLOR_TYPE_GRAY || |
| 39 + | info_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
| 40 + | png_set_gray_to_rgb (png_ptr); |
| 41 + | - /* we can't handle alpha values */ |
| 42 + | - if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA) |
| 43 + | - png_set_strip_alpha (png_ptr); |
| 44 + | /* tell libpng to strip 16 bit depth files down to 8 bits */ |
| 45 + | if (info_ptr->bit_depth == 16) |
| 46 + | png_set_strip_16 (png_ptr); |
| 47 + | |
| 48 + | png_set_packing (png_ptr); |
| 49 + | } |
| 50 + | |
| 51 + | + /* we can't handle alpha values |
| 52 + | + png_read_update_info ensures the alpha flag is set when one of |
| 53 + | + the transforms above causes an alpha channel to be generated */ |
| 54 + | + png_read_update_info (png_ptr, info_ptr); |
| 55 + | + if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA) |
| 56 + | + png_set_strip_alpha (png_ptr); |
| 57 + | + |
| 58 + | png_read_image (png_ptr, row_pointers); |
| 59 + | png_read_end (png_ptr, info_ptr); |
| 60 + |