Re: [ft] A suspicious memory leak in src/truetype/ttgload.c: tt_loader_init

[Grissiom]

On Fri, May 15, 2015 at 8:33 PM, Werner LEMBERG <address@hidden> wrote:

> I'm porting FreeType-2.5.5 to an embedded RTOS. However, I found
> memory leak in looped `FT_Load_Char(fft->face, *text_ptr,
> FT_LOAD_RENDER)` while the memory won't leak if I set the load_flags
> ORed with FT_LOAD_NO_HINTING.
>
> So I dive into the source code and found in the tt_loader_init, the
> `size->bytecode_ready` and `size->cvt_ready` are always -1, causing
> `tt_size_ready_bytecode` run on the same `size` repeatedly. So the
> previous content of size will be leaked.

Please provide a stand-alone, compilable minimum example that exhibits
the problem.  I can then do some debugging.

Sorry for the delay. Here is the program:

===================

#include <unistd.h>
#include <stdint.h>

#include <ft2build.h>
#include FT_FREETYPE_H

#define handle_error(msg, err) \
       do { printf(msg); exit(err); } while (0)

int main(int argc, char *argv[])
{
       FT_Error err = 0;
       FT_Face     face;
       FT_Library  library;

       err = FT_Init_FreeType(&library);
       if (err)
               handle_error("failed to Init FreeType\n", err);

       err = FT_New_Face(library, "digital-number.ttf", 0, &face);
       if (err)
               handle_error("failed to New Face\n", err);

       err = FT_Select_Charmap(face, FT_ENCODING_UNICODE);
       if (err)
       {
               err = FT_Select_Charmap(face, FT_ENCODING_ADOBE_LATIN_1);
       }

       err = FT_Set_Pixel_Sizes(face, 0, 110);
       if (err != 0)
       {
               handle_error("failed to set Pixel Size\n", err);
       }

       for (;;)
       {
               FT_ULong char_code = '0';
               FT_GlyphSlot  slot;

               slot = face->glyph;

               err = FT_Load_Char(face, char_code, FT_LOAD_RENDER);
               if (err)
                       handle_error("failed to load char\n", err);

               usleep(1000);
       }

       return 0;
}

===================

I attached the font as a 7z archive. Compile and run this program you will see the memory usage of the process is going up quickly.

I also figured out that this bug is font specific. I tried an other font and there won't be leaks. My font is generated by FontForge if that matter.

--

Cheers,
Grissiom

digital-number.7z
Description: application/7z-compressed