i try to integrate Lua in a embedded project using GCC on a Cortex-M4. i am able to load and run a Lua script, calling Lua functions from C, calling C functions from Lua. but the C program crashes (HardFault_Handler trap rises) when the given script passed as parameter in luaL_dostring() contains any Lua syntax errors.
here the relevant C code that crashes due to the syntax error in Lua:
//create Lua VM...
luaVm = lua_newstate(luaAlloc, NULL);
//load libraries...
luaopen_base(luaVm);
luaopen_math(luaVm);
luaopen_table(luaVm);
luaopen_string(luaVm);
//launch script...
luaL_dostring(luaVm, "function onTick()\n"
" locaal x = 7\n" //syntax error
"end\n"
"\n" );
when doing the same with correct Lua syntax, then it works:
luaL_dostring(luaVm, "function onTick()\n"
" local x = 7\n"
"end\n"
"\n" );
when debugging and stepping through luaL_dostring(), i can follow the Lua parsing line for line, and when reaching the line with the syntax error, then the C program crashes.
can anybody help? thanks.
have disabled setjmp/longjmp
in Lua source code in the following way:
//#define LUAI_THROW(L,c) longjmp((c)->b, 1) //TODO oli4 orig
//#define LUAI_TRY(L,c,a) if (setjmp((c)->b) == 0) { a } //TODO oli4 orig
#define LUAI_THROW(L,c) while(1) //TODO oli4 special
#define LUAI_TRY(L,c,a) { a } //TODO oli4 special
...so there is no setjmp/longjmp used anymore, but i still have the crash :-(
must have another cause???
found the problem: it is the sprintf function called on Lua syntax error. in fact, on my platform sprintf seems not support floating point presentation. so i changed luaconf.h the following way, limiting the presentation to integer format.
//#define LUA_NUMBER_FMT "%.14g"
#define LUA_NUMBER_FMT "%d"