SDL_LoadObject error message truncated to 128 bytes long

[takase1121]

I'm working on a program that uses SDL_LoadObject to load a SO file. However, an error occured and I can't see the full error message because the SO file path is too long and obscured most of the error message. SDL_SetError() seems to have a 128 byte limit.

Error message:
Failed loading /home/takase/.luarocks/lib64/lua/5.4/ltreesitter.so: /home/takase/.luarocks/lib64/lua/5.4/ltreesitter.so: undefi

You can see that the string is truncated to 127 bytes.

I suggest to omit filenames in the error message. In this case, dlerror() somehow appends the filename and causes wastage.

[adamharrison]

Also just randomly ran into this; independently of takase1121 (though we do randomly work on the same project).

[adamharrison]

Seems like this can be changed by modifying the

#define ERR_MAX_STRLEN 128

line in SDL_error.c.h.

I'm assuming there's a reason this is so low. Would SDL be open to doubling, or quadrupling this number?

[1bsyl]

Previous commit fix an error, I got an error when the error message is reallocated.

==62914== Memcheck, a memory error detector
==62914== Copyright (C) 2002-2022, and GNU GPL'd, by Julian Seward et al.
==62914== Using Valgrind-3.20.0.GIT and LibVEX; rerun with -h for copyright info
==62914== Command: ./main.out
==62914== 
==62914== Invalid read of size 1
==62914==    at 0x484E636: __strlen_sse2 (vg_replace_strmem.c:500)
==62914==    by 0x523ADB0: __vfprintf_internal (vfprintf-internal.c:1517)
==62914==    by 0x524C519: __vsnprintf_internal (vsnprintf.c:114)
==62914==    by 0x495A9E2: SDL_vsnprintf_REAL (SDL_git/src/stdlib/SDL_string.c:1404)
==62914==    by 0x48A9ED8: SDL_SetError_REAL (SDL_git/src/SDL_error.c:47)
==62914==    by 0x4AAB1AC: SDL_LoadFunction_REAL (SDL_git/src/loadso/dlopen/SDL_sysloadso.c:72)
==62914==    by 0x4AB4D66: X11_GetSym (SDL_git/src/video/x11/SDL_x11dyn.c:80)
==62914==    by 0x4AB3BD8: SDL_X11_LoadSymbols (SDL_git/src/video/x11/SDL_x11sym.h:95)
==62914==    by 0x4AC292F: X11_CreateDevice (SDL_git/src/video/x11/SDL_x11video.c:159)
==62914==    by 0x49D00DC: SDL_VideoInit_REAL (SDL_git/src/video/SDL_video.c:453)
==62914==    by 0x48A7B59: SDL_InitSubSystem_REAL (SDL_git/src/SDL.c:251)
==62914==    by 0x48A80E2: SDL_Init_REAL (SDL_git/src/SDL.c:354)
==62914==  Address 0x1 is not stack'd, malloc'd or (recently) free'd
==62914== 
==62914== 
==62914== Process terminating with default action of signal 11 (SIGSEGV)
==62914==  Access not within mapped region at address 0x1
==62914==    at 0x484E636: __strlen_sse2 (vg_replace_strmem.c:500)
==62914==    by 0x523ADB0: __vfprintf_internal (vfprintf-internal.c:1517)
==62914==    by 0x524C519: __vsnprintf_internal (vsnprintf.c:114)
==62914==    by 0x495A9E2: SDL_vsnprintf_REAL (SDL_git/src/stdlib/SDL_string.c:1404)
==62914==    by 0x48A9ED8: SDL_SetError_REAL (SDL_git/src/SDL_error.c:47)
==62914==    by 0x4AAB1AC: SDL_LoadFunction_REAL (SDL_git/src/loadso/dlopen/SDL_sysloadso.c:72)
==62914==    by 0x4AB4D66: X11_GetSym (SDL_git/src/video/x11/SDL_x11dyn.c:80)
==62914==    by 0x4AB3BD8: SDL_X11_LoadSymbols (SDL_git/src/video/x11/SDL_x11sym.h:95)
==62914==    by 0x4AC292F: X11_CreateDevice (SDL_git/src/video/x11/SDL_x11video.c:159)
==62914==    by 0x49D00DC: SDL_VideoInit_REAL (SDL_git/src/video/SDL_video.c:453)
==62914==    by 0x48A7B59: SDL_InitSubSystem_REAL (SDL_git/src/SDL.c:251)
==62914==    by 0x48A80E2: SDL_Init_REAL (SDL_git/src/SDL.c:354)

[1bsyl]

probably the same patch here:

cbd0187#diff-c9d13ae3458a7283597823c15d420ae5bfe15ff45ece5c6d51930df6b0e2f0f7L72

?

[1bsyl]

Applied the same pattern. Anyway the code is not compiled because of #define DISABLE_JUMP_MAGIC 1