Initial commit

engines/grim/lua/lundump.cpp

@@ -0,0 +1,187 @@
+/*
+** load bytecodes from files
+** See Copyright Notice in lua.h
+*/
+
+#include "engines/grim/lua/lauxlib.h"
+#include "engines/grim/lua/lfunc.h"
+#include "engines/grim/lua/lmem.h"
+#include "engines/grim/lua/lstring.h"
+#include "engines/grim/lua/lundump.h"
+
+namespace Grim {
+
+static float conv_float(const byte *data) {
+	float f;
+	byte *fdata = (byte *)(&f);
+	fdata[0] = data[3];
+	fdata[1] = data[2];
+	fdata[2] = data[1];
+	fdata[3] = data[0];
+	return f;
+}
+
+static void unexpectedEOZ(ZIO *Z) {
+	luaL_verror("unexpected end of file in %s", zname(Z));
+}
+
+static int32 ezgetc(ZIO *Z) {
+	int32 c = zgetc(Z);
+	if (c == EOZ)
+		unexpectedEOZ(Z);
+	return c;
+}
+
+static void ezread(ZIO *Z, void *b, int32 n) {
+	int32 r = zread(Z, b, n);
+	if (r)
+		unexpectedEOZ(Z);
+}
+
+static uint16 LoadWord(ZIO *Z) {
+	uint16 hi = ezgetc(Z);
+	uint16 lo = ezgetc(Z);
+	return (hi << 8) | lo;
+}
+
+static void *LoadBlock(int size, ZIO *Z) {
+	void *b = luaM_malloc(size);
+	ezread(Z, b, size);
+	return b;
+}
+
+static uint32 LoadSize(ZIO *Z) {
+	uint32 hi = LoadWord(Z);
+	uint32 lo = LoadWord(Z);
+	return (hi << 16) | lo;
+}
+
+static float LoadFloat(ZIO *Z) {
+	uint32 l = LoadSize(Z);
+	return conv_float((const byte *)&l);
+}
+
+static TaggedString *LoadTString(ZIO *Z) {
+	int32 size = LoadWord(Z);
+	int32 i;
+
+	if (size == 0)
+		return nullptr;
+	else {
+		char *s = luaL_openspace(size);
+		ezread(Z, s, size);
+		for (i = 0; i < size; i++)
+			s[i] ^= 0xff;
+		return luaS_new(s);
+	}
+}
+
+static void LoadLocals(TProtoFunc *tf, ZIO *Z) {
+	int32 i, n = LoadWord(Z);
+	if (n == 0)
+		return;
+	tf->locvars = luaM_newvector(n + 1, LocVar);
+	for (i = 0; i < n; i++) {
+		tf->locvars[i].line = LoadWord(Z);
+		tf->locvars[i].varname = LoadTString(Z);
+	}
+	tf->locvars[i].line = -1; // flag end of vector
+	tf->locvars[i].varname = nullptr;
+}
+
+static void LoadConstants(TProtoFunc *tf, ZIO *Z) {
+	int32 i, n = LoadWord(Z);
+	tf->nconsts = n;
+	if (n == 0)
+		return;
+	tf->consts = luaM_newvector(n, TObject);
+	for (i = 0; i < n; i++) {
+		TObject *o = tf->consts + i;
+		int c = ezgetc(Z);
+		switch (c) {
+		case ID_NUM:
+			ttype(o) = LUA_T_NUMBER;
+			nvalue(o) = LoadFloat(Z);
+			break;
+		case ID_STR:
+			ttype(o) = LUA_T_STRING;
+			tsvalue(o) = LoadTString(Z);
+			break;
+		case ID_FUN:
+			ttype(o) = LUA_T_PROTO;
+			tfvalue(o) = nullptr;
+		default:
+			break;
+		}
+	}
+}
+
+static void LoadFunctions(TProtoFunc *tf, ZIO *Z);
+
+static TProtoFunc *LoadFunction(ZIO *Z) {
+	TProtoFunc *tf = luaF_newproto();
+	tf->lineDefined = LoadWord(Z);
+	tf->fileName = LoadTString(Z);
+	tf->code = (byte *)LoadBlock(LoadSize(Z), Z);
+	LoadConstants(tf, Z);
+	LoadLocals(tf, Z);
+	LoadFunctions(tf, Z);
+
+	return tf;
+}
+
+static void LoadFunctions(TProtoFunc *tf, ZIO *Z) {
+	while (ezgetc(Z) == ID_FUNCTION) {
+		int32 i = LoadWord(Z);
+		TProtoFunc *t = LoadFunction(Z);
+		TObject *o = tf->consts + i;
+		tfvalue(o) = t;
+	}
+}
+
+static void LoadSignature(ZIO *Z) {
+	const char *s = SIGNATURE;
+
+	while (*s && ezgetc(Z) == *s)
+		++s;
+	if (*s)
+		luaL_verror("bad signature in %s", zname(Z));
+}
+
+static void LoadHeader(ZIO *Z) {
+	int32 version, sizeofR;
+
+	LoadSignature(Z);
+	version = ezgetc(Z);
+	if (version > VERSION)
+		luaL_verror("%s too new: version=0x%02x; expected at most 0x%02x", zname(Z), version, VERSION);
+	if (version < VERSION) // check last major change
+		luaL_verror("%s too old: version=0x%02x; expected at least 0x%02x", zname(Z), version, VERSION);
+	sizeofR = ezgetc(Z); // test number representation
+	if (sizeofR != sizeof(float))
+		luaL_verror("number expected float in %s", zname(Z));
+	ezgetc(Z);
+	ezgetc(Z);
+	ezgetc(Z);
+	ezgetc(Z);
+}
+
+static TProtoFunc *LoadChunk(ZIO *Z) {
+	LoadHeader(Z);
+	return LoadFunction(Z);
+}
+
+/*
+** load one chunk from a file or buffer
+** return main if ok and NULL at EOF
+*/
+TProtoFunc *luaU_undump1(ZIO *Z) {
+	int32 c = zgetc(Z);
+	if (c == ID_CHUNK)
+		return LoadChunk(Z);
+	else if (c != EOZ)
+		luaL_verror("%s is not a Lua binary file", zname(Z));
+	return nullptr;
+}
+
+} // end of namespace Grim