iw7-mod/deps/lua/lundump.c
2024-08-13 05:15:34 -04:00

407 lines
10 KiB
C

/*
** $Id: lundump.c $
** load precompiled Lua chunks
** See Copyright Notice in lua.h
*/
#define lundump_c
#define LUA_CORE
#include "lprefix.h"
#include <limits.h>
#include <string.h>
#include "lua.h"
#include "ldebug.h"
#include "ldo.h"
#include "lfunc.h"
#include "lmem.h"
#include "lobject.h"
#include "lstring.h"
#include "ltable.h"
#include "lundump.h"
#include "lzio.h"
#if !defined(luai_verifycode)
#define luai_verifycode(L,f) /* empty */
#endif
typedef struct {
lua_State *L;
ZIO *Z;
const char *name;
Table *h; /* list for string reuse */
size_t offset; /* current position relative to beginning of dump */
lua_Integer nstr; /* number of strings in the list */
lu_byte fixed; /* dump is fixed in memory */
} LoadState;
static l_noret error (LoadState *S, const char *why) {
luaO_pushfstring(S->L, "%s: bad binary format (%s)", S->name, why);
luaD_throw(S->L, LUA_ERRSYNTAX);
}
/*
** All high-level loads go through loadVector; you can change it to
** adapt to the endianness of the input
*/
#define loadVector(S,b,n) loadBlock(S,b,(n)*sizeof((b)[0]))
static void loadBlock (LoadState *S, void *b, size_t size) {
if (luaZ_read(S->Z, b, size) != 0)
error(S, "truncated chunk");
S->offset += size;
}
static void loadAlign (LoadState *S, int align) {
int padding = align - (S->offset % align);
if (padding < align) { /* apd == align means no padding */
lua_Integer paddingContent;
loadBlock(S, &paddingContent, padding);
lua_assert(S->offset % align == 0);
}
}
#define getaddr(S,n,t) cast(t *, getaddr_(S,n,sizeof(t)))
static const void *getaddr_ (LoadState *S, int n, size_t sz) {
size_t size = n * sz;
const void *block = luaZ_getaddr(S->Z, size);
S->offset += size;
if (block == NULL)
error(S, "truncated fixed buffer");
return block;
}
#define loadVar(S,x) loadVector(S,&x,1)
static lu_byte loadByte (LoadState *S) {
int b = zgetc(S->Z);
if (b == EOZ)
error(S, "truncated chunk");
S->offset++;
return cast_byte(b);
}
static size_t loadUnsigned (LoadState *S, size_t limit) {
size_t x = 0;
int b;
limit >>= 7;
do {
b = loadByte(S);
if (x >= limit)
error(S, "integer overflow");
x = (x << 7) | (b & 0x7f);
} while ((b & 0x80) == 0);
return x;
}
static size_t loadSize (LoadState *S) {
return loadUnsigned(S, MAX_SIZET);
}
static int loadInt (LoadState *S) {
return cast_int(loadUnsigned(S, INT_MAX));
}
static lua_Number loadNumber (LoadState *S) {
lua_Number x;
loadVar(S, x);
return x;
}
static lua_Integer loadInteger (LoadState *S) {
lua_Integer x;
loadVar(S, x);
return x;
}
/*
** Load a nullable string into slot 'sl' from prototype 'p'. The
** assignment to the slot and the barrier must be performed before any
** possible GC activity, to anchor the string. (Both 'loadVector' and
** 'luaH_setint' can call the GC.)
*/
static void loadString (LoadState *S, Proto *p, TString **sl) {
lua_State *L = S->L;
TString *ts;
TValue sv;
size_t size = loadSize(S);
if (size == 0) { /* no string? */
lua_assert(*sl == NULL); /* must be prefilled */
return;
}
else if (size == 1) { /* previously saved string? */
int idx = loadInt(S); /* get its index */
TValue stv;
luaH_getint(S->h, idx, &stv);
*sl = ts = tsvalue(&stv);
luaC_objbarrier(L, p, ts);
return; /* do not save it again */
}
else if ((size -= 2) <= LUAI_MAXSHORTLEN) { /* short string? */
char buff[LUAI_MAXSHORTLEN + 1]; /* extra space for '\0' */
loadVector(S, buff, size + 1); /* load string into buffer */
*sl = ts = luaS_newlstr(L, buff, size); /* create string */
luaC_objbarrier(L, p, ts);
}
else if (S->fixed) { /* for a fixed buffer, use a fixed string */
const char *s = getaddr(S, size + 1, char); /* get content address */
*sl = ts = luaS_newextlstr(L, s, size, NULL, NULL);
luaC_objbarrier(L, p, ts);
}
else { /* create internal copy */
*sl = ts = luaS_createlngstrobj(L, size); /* create string */
luaC_objbarrier(L, p, ts);
loadVector(S, getlngstr(ts), size + 1); /* load directly in final place */
}
/* add string to list of saved strings */
S->nstr++;
setsvalue(L, &sv, ts);
luaH_setint(L, S->h, S->nstr, &sv);
luaC_objbarrierback(L, obj2gco(S->h), ts);
}
static void loadCode (LoadState *S, Proto *f) {
int n = loadInt(S);
loadAlign(S, sizeof(f->code[0]));
if (S->fixed) {
f->code = getaddr(S, n, Instruction);
f->sizecode = n;
}
else {
f->code = luaM_newvectorchecked(S->L, n, Instruction);
f->sizecode = n;
loadVector(S, f->code, n);
}
}
static void loadFunction(LoadState *S, Proto *f);
static void loadConstants (LoadState *S, Proto *f) {
int i;
int n = loadInt(S);
f->k = luaM_newvectorchecked(S->L, n, TValue);
f->sizek = n;
for (i = 0; i < n; i++)
setnilvalue(&f->k[i]);
for (i = 0; i < n; i++) {
TValue *o = &f->k[i];
int t = loadByte(S);
switch (t) {
case LUA_VNIL:
setnilvalue(o);
break;
case LUA_VFALSE:
setbfvalue(o);
break;
case LUA_VTRUE:
setbtvalue(o);
break;
case LUA_VNUMFLT:
setfltvalue(o, loadNumber(S));
break;
case LUA_VNUMINT:
setivalue(o, loadInteger(S));
break;
case LUA_VSHRSTR:
case LUA_VLNGSTR: {
lua_assert(f->source == NULL);
loadString(S, f, &f->source); /* use 'source' to anchor string */
if (f->source == NULL)
error(S, "bad format for constant string");
setsvalue2n(S->L, o, f->source); /* save it in the right place */
f->source = NULL;
break;
}
default: lua_assert(0);
}
}
}
static void loadProtos (LoadState *S, Proto *f) {
int i;
int n = loadInt(S);
f->p = luaM_newvectorchecked(S->L, n, Proto *);
f->sizep = n;
for (i = 0; i < n; i++)
f->p[i] = NULL;
for (i = 0; i < n; i++) {
f->p[i] = luaF_newproto(S->L);
luaC_objbarrier(S->L, f, f->p[i]);
loadFunction(S, f->p[i]);
}
}
/*
** Load the upvalues for a function. The names must be filled first,
** because the filling of the other fields can raise read errors and
** the creation of the error message can call an emergency collection;
** in that case all prototypes must be consistent for the GC.
*/
static void loadUpvalues (LoadState *S, Proto *f) {
int i, n;
n = loadInt(S);
f->upvalues = luaM_newvectorchecked(S->L, n, Upvaldesc);
f->sizeupvalues = n;
for (i = 0; i < n; i++) /* make array valid for GC */
f->upvalues[i].name = NULL;
for (i = 0; i < n; i++) { /* following calls can raise errors */
f->upvalues[i].instack = loadByte(S);
f->upvalues[i].idx = loadByte(S);
f->upvalues[i].kind = loadByte(S);
}
}
static void loadDebug (LoadState *S, Proto *f) {
int i, n;
n = loadInt(S);
if (S->fixed) {
f->lineinfo = getaddr(S, n, ls_byte);
f->sizelineinfo = n;
}
else {
f->lineinfo = luaM_newvectorchecked(S->L, n, ls_byte);
f->sizelineinfo = n;
loadVector(S, f->lineinfo, n);
}
n = loadInt(S);
if (n > 0) {
loadAlign(S, sizeof(int));
if (S->fixed) {
f->abslineinfo = getaddr(S, n, AbsLineInfo);
f->sizeabslineinfo = n;
}
else {
f->abslineinfo = luaM_newvectorchecked(S->L, n, AbsLineInfo);
f->sizeabslineinfo = n;
loadVector(S, f->abslineinfo, n);
}
}
n = loadInt(S);
f->locvars = luaM_newvectorchecked(S->L, n, LocVar);
f->sizelocvars = n;
for (i = 0; i < n; i++)
f->locvars[i].varname = NULL;
for (i = 0; i < n; i++) {
loadString(S, f, &f->locvars[i].varname);
f->locvars[i].startpc = loadInt(S);
f->locvars[i].endpc = loadInt(S);
}
n = loadInt(S);
if (n != 0) /* does it have debug information? */
n = f->sizeupvalues; /* must be this many */
for (i = 0; i < n; i++)
loadString(S, f, &f->upvalues[i].name);
}
static void loadFunction (LoadState *S, Proto *f) {
f->linedefined = loadInt(S);
f->lastlinedefined = loadInt(S);
f->numparams = loadByte(S);
f->flag = loadByte(S) & PF_ISVARARG; /* get only the meaningful flags */
if (S->fixed)
f->flag |= PF_FIXED; /* signal that code is fixed */
f->maxstacksize = loadByte(S);
loadCode(S, f);
loadConstants(S, f);
loadUpvalues(S, f);
loadProtos(S, f);
loadString(S, f, &f->source);
loadDebug(S, f);
}
static void checkliteral (LoadState *S, const char *s, const char *msg) {
char buff[sizeof(LUA_SIGNATURE) + sizeof(LUAC_DATA)]; /* larger than both */
size_t len = strlen(s);
loadVector(S, buff, len);
if (memcmp(s, buff, len) != 0)
error(S, msg);
}
static void fchecksize (LoadState *S, size_t size, const char *tname) {
if (loadByte(S) != size)
error(S, luaO_pushfstring(S->L, "%s size mismatch", tname));
}
#define checksize(S,t) fchecksize(S,sizeof(t),#t)
static void checkHeader (LoadState *S) {
/* skip 1st char (already read and checked) */
checkliteral(S, &LUA_SIGNATURE[1], "not a binary chunk");
if (loadByte(S) != LUAC_VERSION)
error(S, "version mismatch");
if (loadByte(S) != LUAC_FORMAT)
error(S, "format mismatch");
checkliteral(S, LUAC_DATA, "corrupted chunk");
checksize(S, Instruction);
checksize(S, lua_Integer);
checksize(S, lua_Number);
if (loadInteger(S) != LUAC_INT)
error(S, "integer format mismatch");
if (loadNumber(S) != LUAC_NUM)
error(S, "float format mismatch");
}
/*
** Load precompiled chunk.
*/
LClosure *luaU_undump (lua_State *L, ZIO *Z, const char *name, int fixed) {
LoadState S;
LClosure *cl;
if (*name == '@' || *name == '=')
S.name = name + 1;
else if (*name == LUA_SIGNATURE[0])
S.name = "binary string";
else
S.name = name;
S.L = L;
S.Z = Z;
S.fixed = fixed;
S.offset = 1; /* fist byte was already read */
checkHeader(&S);
cl = luaF_newLclosure(L, loadByte(&S));
setclLvalue2s(L, L->top.p, cl);
luaD_inctop(L);
S.h = luaH_new(L); /* create list of saved strings */
S.nstr = 0;
sethvalue2s(L, L->top.p, S.h); /* anchor it */
luaD_inctop(L);
cl->p = luaF_newproto(L);
luaC_objbarrier(L, cl, cl->p);
loadFunction(&S, cl->p);
lua_assert(cl->nupvalues == cl->p->sizeupvalues);
luai_verifycode(L, cl->p);
L->top.p--; /* pop table */
return cl;
}