luaL_loadbuffer not working with big buffers

[RodrigoDornelles]

I try sizes that would possibly fit on the psx like less than 5Kb, but the console is crashing.

[nicolasnoble]

Do you have some reproduction code for us to try?

[RodrigoDornelles]

@nicolasnoble actually it's some random sizes, I still don't understand the error behavior, if you change this_code_works to this_code_causes_blackscreen you will see that the game will not boot.

Sorry for the example being too long, I tried to keep it simple.

when buffer size is 140, 139.. or 160 not work, but 138 works (correct or incorrect code)

pases

function native_callback_init(g,w,h)end
function native_callback_loop(d)end
function native_callback_draw()native_draw_rect(0,1,1,9,20)end

not work

function native_callback_init(game, w, h)
end
function native_callback_loop(dt)
end
function native_callback_draw()
    native_draw_rect(0, 10, 10, 20, 20)
end

example code

#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <psxgpu.h>
#include "luapsx/src/lua.h"
#include "luapsx/src/lualib.h"
#include "luapsx/src/lauxlib.h"

#define OT_LENGTH 16
#define BUFFER_LENGTH 8192

typedef struct {
	DISPENV disp_env;
	DRAWENV draw_env;

	uint32_t ot[OT_LENGTH];
	uint8_t  buffer[BUFFER_LENGTH];
} RenderBuffer;

typedef struct {
	RenderBuffer buffers[2];
	uint8_t      *next_packet;
	int          active_buffer;
} RenderContext;

void setup_context(RenderContext *ctx, int w, int h, int r, int g, int b) {
	SetDefDrawEnv(&(ctx->buffers[0].draw_env), 0, 0, w, h);
	SetDefDispEnv(&(ctx->buffers[0].disp_env), 0, 0, w, h);
	SetDefDrawEnv(&(ctx->buffers[1].draw_env), 0, h, w, h);
	SetDefDispEnv(&(ctx->buffers[1].disp_env), 0, h, w, h);

	setRGB0(&(ctx->buffers[0].draw_env), r, g, b);
	setRGB0(&(ctx->buffers[1].draw_env), r, g, b);
	ctx->buffers[0].draw_env.isbg = 1;
	ctx->buffers[1].draw_env.isbg = 1;

	ctx->active_buffer = 0;
	ctx->next_packet   = ctx->buffers[0].buffer;
	ClearOTagR(ctx->buffers[0].ot, OT_LENGTH);

	SetDispMask(1);
}

void flip_buffers(RenderContext *ctx) {
	DrawSync(0);
	VSync(0);

	RenderBuffer *draw_buffer = &(ctx->buffers[ctx->active_buffer]);
	RenderBuffer *disp_buffer = &(ctx->buffers[ctx->active_buffer ^ 1]);

	PutDispEnv(&(disp_buffer->disp_env));
	DrawOTagEnv(&(draw_buffer->ot[OT_LENGTH - 1]), &(draw_buffer->draw_env));

	ctx->active_buffer ^= 1;
	ctx->next_packet    = disp_buffer->buffer;
	ClearOTagR(disp_buffer->ot, OT_LENGTH);
}

void *new_primitive(RenderContext *ctx, int z, size_t size) {
	RenderBuffer *buffer = &(ctx->buffers[ctx->active_buffer]);
	uint8_t      *prim   = ctx->next_packet;

	addPrim(&(buffer->ot[z]), prim);
	ctx->next_packet += size;

	assert(ctx->next_packet <= &(buffer->buffer[BUFFER_LENGTH]));

	return (void *) prim;
}

void draw_text(RenderContext *ctx, int x, int y, int z, const char *text) {
	RenderBuffer *buffer = &(ctx->buffers[ctx->active_buffer]);

	ctx->next_packet = (uint8_t *)
		FntSort(&(buffer->ot[z]), ctx->next_packet, x, y, text);

	assert(ctx->next_packet <= &(buffer->buffer[BUFFER_LENGTH]));
}

#define SCREEN_XRES 320
#define SCREEN_YRES 240

int main(int argc, const char **argv) {
    lua_State *L;

    L = luaL_newstate();

    luaL_openlibs(L);

	ResetGraph(0);
	FntLoad(960, 0);

	static char this_code_works[] = "return 1";
	static char this_code_causes_blackscreen[] = "function native_callback_init(game, w, h)\n"
	"end\n"
	"function native_callback_loop(dt)\n"
	"end\n"
	"function native_callback_draw()\n"
	"    native_draw_rect(0, 10, 10, 20, 20)\n"
	"end\n";
	luaL_loadbuffer(L, this_code_works, sizeof(this_code_works) - 1, "?");
	//luaL_loadbuffer(L, this_code_causes_blackscreen, sizeof(this_code_causes_blackscreen) - 1, "?");


	RenderContext ctx;
	setup_context(&ctx, SCREEN_XRES, SCREEN_YRES, 63, 0, 127);

	int x  = 0, y  = 0;
	int dx = 1, dy = 1;

	for (;;) {
		if (x < 0 || x > (SCREEN_XRES - 64))
			dx = -dx;
		if (y < 0 || y > (SCREEN_YRES - 64))
			dy = -dy;
		x += dx;
		y += dy;
		TILE *tile = (TILE *) new_primitive(&ctx, 1, sizeof(TILE));
		setTile(tile);
		setXY0 (tile, x, y);
		setWH  (tile, 64, 64);
		setRGB0(tile, 255, 255, 0);
		draw_text(&ctx, 8, 16, 0, "Hello world!");
		flip_buffers(&ctx);
	}

	return 0;
}

[RodrigoDornelles]

@nicolasnoble When I use bytecode this problem does not occur, even with large programs, it must be a heavy use of memory during lua 5.2 parsing.