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/* vim: ts=4 sw=4 sts=4 et tw=78
* Copyright (c) 2011 James R. McKaskill. See license in ffi.h
*/
#include "ffi.h"
#define IS_CONST(tok) (IS_LITERAL(tok, "const") || IS_LITERAL(tok, "__const") || IS_LITERAL(tok, "__const__"))
#define IS_VOLATILE(tok) (IS_LITERAL(tok, "volatile") || IS_LITERAL(tok, "__volatile") || IS_LITERAL(tok, "__volatile__"))
#define IS_RESTRICT(tok) (IS_LITERAL(tok, "restrict") || IS_LITERAL(tok, "__restrict") || IS_LITERAL(tok, "__restrict__"))
enum etoken {
TOK_NIL,
TOK_NUMBER,
TOK_STRING,
TOK_TOKEN,
/* the order of these values must match the token strings in lex.c */
TOK_3_BEGIN,
TOK_VA_ARG,
TOK_2_BEGIN,
TOK_LEFT_SHIFT, TOK_RIGHT_SHIFT, TOK_LOGICAL_AND, TOK_LOGICAL_OR, TOK_LESS_EQUAL,
TOK_GREATER_EQUAL, TOK_EQUAL, TOK_NOT_EQUAL,
TOK_1_BEGIN,
TOK_OPEN_CURLY, TOK_CLOSE_CURLY, TOK_SEMICOLON, TOK_COMMA, TOK_COLON,
TOK_ASSIGN, TOK_OPEN_PAREN, TOK_CLOSE_PAREN, TOK_OPEN_SQUARE, TOK_CLOSE_SQUARE,
TOK_DOT, TOK_AMPERSAND, TOK_LOGICAL_NOT, TOK_BITWISE_NOT, TOK_MINUS,
TOK_PLUS, TOK_STAR, TOK_DIVIDE, TOK_MODULUS, TOK_LESS,
TOK_GREATER, TOK_BITWISE_XOR, TOK_BITWISE_OR, TOK_QUESTION, TOK_POUND,
TOK_REFERENCE = TOK_AMPERSAND,
TOK_MULTIPLY = TOK_STAR,
TOK_BITWISE_AND = TOK_AMPERSAND,
};
struct token {
enum etoken type;
int64_t integer;
const char* str;
size_t size;
};
#define IS_LITERAL(TOK, STR) \
(((TOK).size == sizeof(STR) - 1) && 0 == memcmp((TOK).str, STR, sizeof(STR) - 1))
/* the order of tokens _must_ match the order of the enum etoken enum */
static char tok3[][4] = {
"...", /* unused ">>=", "<<=", */
};
static char tok2[][3] = {
"<<", ">>", "&&", "||", "<=",
">=", "==", "!=",
/* unused "+=", "-=", "*=", "/=", "%=", "&=", "^=", "|=", "++", "--", "->", "::", */
};
static char tok1[] = {
'{', '}', ';', ',', ':',
'=', '(', ')', '[', ']',
'.', '&', '!', '~', '-',
'+', '*', '/', '%', '<',
'>', '^', '|', '?', '#'
};
static int next_token(lua_State* L, struct parser* P, struct token* tok)
{
size_t i;
const char* s = P->next;
/* UTF8 BOM */
if (s[0] == '\xEF' && s[1] == '\xBB' && s[2] == '\xBF') {
s += 3;
}
/* consume whitespace and comments */
for (;;) {
/* consume whitespace */
while(*s == '\t' || *s == '\n' || *s == ' ' || *s == '\v' || *s == '\r') {
if (*s == '\n') {
P->line++;
}
s++;
}
/* consume comments */
if (*s == '/' && *(s+1) == '/') {
s = strchr(s, '\n');
if (!s) {
luaL_error(L, "non-terminated comment");
}
} else if (*s == '/' && *(s+1) == '*') {
s += 2;
for (;;) {
if (s[0] == '\0') {
luaL_error(L, "non-terminated comment");
} else if (s[0] == '*' && s[1] == '/') {
s += 2;
break;
} else if (s[0] == '\n') {
P->line++;
}
s++;
}
} else if (*s == '\0') {
tok->type = TOK_NIL;
return 0;
} else {
break;
}
}
P->prev = s;
for (i = 0; i < sizeof(tok3) / sizeof(tok3[0]); i++) {
if (s[0] == tok3[i][0] && s[1] == tok3[i][1] && s[2] == tok3[i][2]) {
tok->type = (enum etoken) (TOK_3_BEGIN + 1 + i);
P->next = s + 3;
goto end;
}
}
for (i = 0; i < sizeof(tok2) / sizeof(tok2[0]); i++) {
if (s[0] == tok2[i][0] && s[1] == tok2[i][1]) {
tok->type = (enum etoken) (TOK_2_BEGIN + 1 + i);
P->next = s + 2;
goto end;
}
}
for (i = 0; i < sizeof(tok1) / sizeof(tok1[0]); i++) {
if (s[0] == tok1[i]) {
tok->type = (enum etoken) (TOK_1_BEGIN + 1 + i);
P->next = s + 1;
goto end;
}
}
if (*s == '.' || *s == '-' || ('0' <= *s && *s <= '9')) {
/* number */
tok->type = TOK_NUMBER;
/* split out the negative case so we get the full range of bits for
* unsigned (eg to support 0xFFFFFFFF where sizeof(long) == 4)
*/
if (*s == '-') {
tok->integer = strtol(s, (char**) &s, 0);
} else {
tok->integer = strtoul(s, (char**) &s, 0);
}
while (*s == 'u' || *s == 'U' || *s == 'l' || *s == 'L') {
s++;
}
P->next = s;
goto end;
} else if (*s == '\'' || *s == '\"') {
/* "..." or '...' */
char quote = *s;
s++; /* jump over " */
tok->type = TOK_STRING;
tok->str = s;
while (*s != quote) {
if (*s == '\0' || (*s == '\\' && *(s+1) == '\0')) {
return luaL_error(L, "string not finished");
}
if (*s == '\\') {
s++;
}
s++;
}
tok->size = s - tok->str;
s++; /* jump over " */
P->next = s;
goto end;
} else if (('a' <= *s && *s <= 'z') || ('A' <= *s && *s <= 'Z') || *s == '_') {
/* tokens */
tok->type = TOK_TOKEN;
tok->str = s;
while (('a' <= *s && *s <= 'z') || ('A' <= *s && *s <= 'Z') || *s == '_' || ('0' <= *s && *s <= '9')) {
s++;
}
tok->size = s - tok->str;
P->next = s;
goto end;
} else {
return luaL_error(L, "invalid character %d", P->line);
}
end:
/*fprintf(stderr, "token %d %d %.*s %.10s\n", tok->type, (int) tok->size, (tok->type == TOK_TOKEN || tok->type == TOK_STRING) ? (int) tok->size : 0, tok->str, P->next);*/
return 1;
}
static void require_token(lua_State* L, struct parser* P, struct token* tok)
{
if (!next_token(L, P, tok)) {
luaL_error(L, "unexpected end");
}
}
static void check_token(lua_State* L, struct parser* P, int type, const char* str, const char* err, ...)
{
struct token tok;
if (!next_token(L, P, &tok) || tok.type != type || (tok.type == TOK_TOKEN && (tok.size != strlen(str) || memcmp(tok.str, str, tok.size) != 0))) {
va_list ap;
va_start(ap, err);
lua_pushvfstring(L, err, ap);
lua_error(L);
}
}
static void put_back(struct parser* P)
{ P->next = P->prev; }
int64_t calculate_constant(lua_State* L, struct parser* P);
static int g_name_key;
static int g_front_name_key;
static int g_back_name_key;
#ifndef max
#define max(a,b) ((a) < (b) ? (b) : (a))
#endif
#ifndef min
#define min(a,b) ((a) < (b) ? (a) : (b))
#endif
enum test {TEST};
/* Parses an enum definition from after the open curly through to the close
* curly. Expects the user table to be on the top of the stack
*/
static int parse_enum(lua_State* L, struct parser* P, struct ctype* type)
{
struct token tok;
int value = -1;
int ct_usr = lua_gettop(L);
for (;;) {
require_token(L, P, &tok);
assert(lua_gettop(L) == ct_usr);
if (tok.type == TOK_CLOSE_CURLY) {
break;
} else if (tok.type != TOK_TOKEN) {
return luaL_error(L, "unexpected token in enum at line %d", P->line);
}
lua_pushlstring(L, tok.str, tok.size);
require_token(L, P, &tok);
if (tok.type == TOK_COMMA || tok.type == TOK_CLOSE_CURLY) {
/* we have an auto calculated enum value */
value++;
} else if (tok.type == TOK_ASSIGN) {
/* we have an explicit enum value */
value = (int) calculate_constant(L, P);
require_token(L, P, &tok);
} else {
return luaL_error(L, "unexpected token in enum at line %d", P->line);
}
assert(lua_gettop(L) == ct_usr + 1);
/* add the enum value to the constants table */
push_upval(L, &constants_key);
lua_pushvalue(L, -2);
lua_pushnumber(L, value);
lua_rawset(L, -3);
lua_pop(L, 1);
assert(lua_gettop(L) == ct_usr + 1);
/* add the enum value to the enum usr value table */
lua_pushnumber(L, value);
lua_rawset(L, ct_usr);
if (tok.type == TOK_CLOSE_CURLY) {
break;
} else if (tok.type != TOK_COMMA) {
return luaL_error(L, "unexpected token in enum at line %d", P->line);
}
}
type->base_size = sizeof(enum test);
type->align_mask = sizeof(enum test) - 1;
assert(lua_gettop(L) == ct_usr);
return 0;
}
static void calculate_member_position(lua_State* L, struct parser* P, struct ctype* ct, struct ctype* mt, int* pbit_offset, int* pbitfield_type)
{
int bit_offset = *pbit_offset;
if (ct->type == UNION_TYPE) {
size_t msize;
if (mt->is_variable_struct || mt->is_variable_array) {
luaL_error(L, "NYI: variable sized members in unions");
return;
} else if (mt->is_bitfield) {
msize = (mt->align_mask + 1);
#ifdef _WIN32
/* MSVC has a bug where it doesn't update the alignment of
* a union for bitfield members. */
mt->align_mask = 0;
#endif
} else if (mt->is_array) {
msize = mt->array_size * (mt->pointers > 1 ? sizeof(void*) : mt->base_size);
} else {
msize = mt->pointers ? sizeof(void*) : mt->base_size;
}
ct->base_size = max(ct->base_size, msize);
} else if (mt->is_bitfield) {
if (mt->has_member_name && mt->bit_size == 0) {
luaL_error(L, "zero length bitfields must be unnamed on line %d", P->line);
}
#if defined _WIN32
/* MSVC uses a seperate storage unit for each size. This is aligned
* before the first bitfield. :0 finishes up the storage unit using
* the greater alignment of the storage unit or the type used with the
* :0. This is equivalent to the :0 always creating a new storage
* unit, but not necesserily using it yet.
*/
if (*pbitfield_type == -1 && mt->bit_size == 0) {
/* :0 not after a bitfield are ignored */
return;
}
{
int different_storage = mt->align_mask != *pbitfield_type;
int no_room_left = bit_offset + mt->bit_size > (mt->align_mask + 1) * CHAR_BIT;
if (different_storage || no_room_left || !mt->bit_size) {
ct->base_size += (bit_offset + CHAR_BIT - 1) / CHAR_BIT;
bit_offset = 0;
if (*pbitfield_type >= 0) {
ct->base_size = ALIGN_UP(ct->base_size, *pbitfield_type);
}
ct->base_size = ALIGN_UP(ct->base_size, mt->align_mask);
}
}
mt->bit_offset = bit_offset;
mt->offset = ct->base_size;
*pbitfield_type = mt->align_mask;
bit_offset += mt->bit_size;
#elif defined OS_OSX
/* OSX doesn't use containers and bitfields are not aligned. So
* bitfields never add any padding, except for :0 which still forces
* an alignment based off the type used with the :0 */
if (mt->bit_size) {
mt->offset = ct->base_size;
mt->bit_offset = bit_offset;
bit_offset += mt->bit_size;
ct->base_size += bit_offset / CHAR_BIT;
bit_offset = bit_offset % CHAR_BIT;
} else {
ct->base_size += (bit_offset + CHAR_BIT - 1) / CHAR_BIT;
ct->base_size = ALIGN_UP(ct->base_size, mt->align_mask);
bit_offset = 0;
}
if (!mt->has_member_name) {
/* unnamed bitfields don't update the struct alignment */
mt->align_mask = 0;
}
#elif defined __GNUC__
/* GCC tries to pack bitfields in as close as much as possible, but
* still making sure that they don't cross alignment boundaries.
* :0 forces an alignment based off the type used with the :0
*/
int bits_used = (ct->base_size - ALIGN_DOWN(ct->base_size, mt->align_mask)) * CHAR_BIT + bit_offset;
int need_to_realign = bits_used + mt->bit_size > mt->base_size * CHAR_BIT;
if (!mt->is_packed && (!mt->bit_size || need_to_realign)) {
ct->base_size += (bit_offset + CHAR_BIT - 1) / CHAR_BIT;
ct->base_size = ALIGN_UP(ct->base_size, mt->align_mask);
bit_offset = 0;
}
mt->bit_offset = bit_offset;
mt->offset = ct->base_size;
bit_offset += mt->bit_size;
ct->base_size += bit_offset / CHAR_BIT;
bit_offset = bit_offset % CHAR_BIT;
/* unnamed bitfields don't update the struct alignment */
if (!mt->has_member_name) {
mt->align_mask = 0;
}
#else
#error
#endif
} else {
/* finish up the current bitfield storage unit */
ct->base_size += (bit_offset + CHAR_BIT - 1) / CHAR_BIT;
bit_offset = 0;
if (*pbitfield_type >= 0) {
ct->base_size = ALIGN_UP(ct->base_size, *pbitfield_type);
}
*pbitfield_type = -1;
ct->base_size = ALIGN_UP(ct->base_size, mt->align_mask);
mt->offset = ct->base_size;
if (mt->is_variable_array) {
ct->is_variable_struct = 1;
ct->variable_increment = mt->pointers > 1 ? sizeof(void*) : mt->base_size;
} else if (mt->is_variable_struct) {
assert(!mt->variable_size_known && !mt->is_array && !mt->pointers);
ct->base_size += mt->base_size;
ct->is_variable_struct = 1;
ct->variable_increment = mt->variable_increment;
} else if (mt->is_array) {
ct->base_size += mt->array_size * (mt->pointers > 1 ? sizeof(void*) : mt->base_size);
} else {
ct->base_size += mt->pointers ? sizeof(void*) : mt->base_size;
}
}
/* increase the outer struct/union alignment if needed */
if (mt->align_mask > (int) ct->align_mask) {
ct->align_mask = mt->align_mask;
}
if (mt->has_bitfield || mt->is_bitfield) {
ct->has_bitfield = 1;
}
*pbit_offset = bit_offset;
}
static int copy_submembers(lua_State* L, int to_usr, int from_usr, const struct ctype* ft, int* midx)
{
struct ctype ct;
int i, sublen;
from_usr = lua_absindex(L, from_usr);
to_usr = lua_absindex(L, to_usr);
/* integer keys */
sublen = (int) lua_rawlen(L, from_usr);
for (i = 1; i <= sublen; i++) {
lua_rawgeti(L, from_usr, i);
ct = *(const struct ctype*) lua_touserdata(L, -1);
ct.offset += ft->offset;
lua_getuservalue(L, -1);
push_ctype(L, -1, &ct);
lua_rawseti(L, to_usr, (*midx)++);
lua_pop(L, 2); /* ctype, user value */
}
/* string keys */
lua_pushnil(L);
while (lua_next(L, from_usr)) {
if (lua_type(L, -2) == LUA_TSTRING) {
struct ctype ct = *(const struct ctype*) lua_touserdata(L, -1);
ct.offset += ft->offset;
lua_getuservalue(L, -1);
/* uservalue[sub_mname] = new_sub_mtype */
lua_pushvalue(L, -3);
push_ctype(L, -2, &ct);
lua_rawset(L, to_usr);
lua_pop(L, 1); /* remove submember user value */
}
lua_pop(L, 1);
}
return 0;
}
static int add_member(lua_State* L, int ct_usr, int mname, int mbr_usr, const struct ctype* mt, int* midx)
{
ct_usr = lua_absindex(L, ct_usr);
mname = lua_absindex(L, mname);
push_ctype(L, mbr_usr, mt);
/* usrvalue[mbr index] = pushed mtype */
lua_pushvalue(L, -1);
lua_rawseti(L, ct_usr, (*midx)++);
/* set usrvalue[mname] = pushed mtype */
lua_pushvalue(L, mname);
lua_pushvalue(L, -2);
lua_rawset(L, ct_usr);
/* set usrvalue[mtype] = mname */
lua_pushvalue(L, -1);
lua_pushvalue(L, mname);
lua_rawset(L, ct_usr);
lua_pop(L, 1);
return 0;
}
/* Parses a struct from after the open curly through to the close curly.
*/
static int parse_struct(lua_State* L, struct parser* P, int tmp_usr, const struct ctype* ct)
{
struct token tok;
int midx = 1;
int top = lua_gettop(L);
tmp_usr = lua_absindex(L, tmp_usr);
/* parse members */
for (;;) {
struct ctype mbase;
assert(lua_gettop(L) == top);
/* see if we're at the end of the struct */
require_token(L, P, &tok);
if (tok.type == TOK_CLOSE_CURLY) {
break;
} else if (ct->is_variable_struct) {
return luaL_error(L, "can't have members after a variable sized member on line %d", P->line);
} else {
put_back(P);
}
/* members are of the form
* <base type> <arg>, <arg>, <arg>;
* eg struct foo bar, *bar2[2];
* mbase is 'struct foo'
* mtype is '' then '*[2]'
* mname is 'bar' then 'bar2'
*/
parse_type(L, P, &mbase);
for (;;) {
struct token mname;
struct ctype mt = mbase;
memset(&mname, 0, sizeof(mname));
if (ct->is_variable_struct) {
return luaL_error(L, "can't have members after a variable sized member on line %d", P->line);
}
assert(lua_gettop(L) == top + 1);
parse_argument(L, P, -1, &mt, &mname, NULL);
assert(lua_gettop(L) == top + 2);
if (!mt.is_defined && (mt.pointers - mt.is_array) == 0) {
return luaL_error(L, "member type is undefined on line %d", P->line);
}
if (mt.type == VOID_TYPE && (mt.pointers - mt.is_array) == 0) {
return luaL_error(L, "member type can not be void on line %d", P->line);
}
mt.has_member_name = (mname.size > 0);
lua_pushlstring(L, mname.str, mname.size);
add_member(L, tmp_usr, -1, -2, &mt, &midx);
/* pop the usr value from push_argument and the member name */
lua_pop(L, 2);
assert(lua_gettop(L) == top + 1);
require_token(L, P, &tok);
if (tok.type == TOK_SEMICOLON) {
break;
} else if (tok.type != TOK_COMMA) {
luaL_error(L, "unexpected token in struct definition on line %d", P->line);
}
}
/* pop the usr value from push_type */
lua_pop(L, 1);
}
assert(lua_gettop(L) == top);
return 0;
}
static int calculate_struct_offsets(lua_State* L, struct parser* P, int ct_usr, struct ctype* ct, int tmp_usr)
{
int i;
int midx = 1;
int sz = (int) lua_rawlen(L, tmp_usr);
int bit_offset = 0;
int bitfield_type = -1;
ct_usr = lua_absindex(L, ct_usr);
tmp_usr = lua_absindex(L, tmp_usr);
for (i = 1; i <= sz; i++) {
struct ctype mt;
/* get the member type */
lua_rawgeti(L, tmp_usr, i);
mt = *(const struct ctype*) lua_touserdata(L, -1);
/* get the member user table */
lua_getuservalue(L, -1);
/* get the member name */
lua_pushvalue(L, -2);
lua_rawget(L, tmp_usr);
calculate_member_position(L, P, ct, &mt, &bit_offset, &bitfield_type);
if (mt.has_member_name) {
assert(!lua_isnil(L, -1));
add_member(L, ct_usr, -1, -2, &mt, &midx);
} else if (mt.type == STRUCT_TYPE || mt.type == UNION_TYPE) {
/* With an unnamed member we copy all of the submembers into our
* usr value adjusting the offset as necessary. Note ctypes are
* immutable so need to push a new ctype to update the offset.
*/
copy_submembers(L, ct_usr, -2, &mt, &midx);
} else {
/* We ignore unnamed members that aren't structs or unions. These
* are there just to change the padding */
}
lua_pop(L, 3);
}
/* finish up the current bitfield storage unit */
ct->base_size += (bit_offset + CHAR_BIT - 1) / CHAR_BIT;
/* only void is allowed 0 size */
if (ct->base_size == 0) {
ct->base_size = 1;
}
ct->base_size = ALIGN_UP(ct->base_size, ct->align_mask);
return 0;
}
/* copy over attributes that could be specified before the typedef eg
* __attribute__(packed) const type_t */
static void instantiate_typedef(struct parser* P, struct ctype* tt, const struct ctype* ft)
{
struct ctype pt = *tt;
*tt = *ft;
tt->const_mask = pt.const_mask;
tt->is_packed = pt.is_packed;
if (tt->is_packed) {
tt->align_mask = 0;
} else {
/* Instantiate the typedef in the current packing. This may be
* further updated if a pointer is added or another alignment
* attribute is applied. If pt.align_mask is already non-zero than an
* increased alignment via __declspec(aligned(#)) has been set. */
tt->align_mask = max(min(P->align_mask, tt->align_mask), pt.align_mask);
}
}
/* this parses a struct or union starting with the optional
* name before the opening brace
* leaves the type usr value on the stack
*/
static int parse_record(lua_State* L, struct parser* P, struct ctype* ct)
{
struct token tok;
int top = lua_gettop(L);
require_token(L, P, &tok);
/* name is optional */
if (tok.type == TOK_TOKEN) {
/* declaration */
lua_pushlstring(L, tok.str, tok.size);
assert(lua_gettop(L) == top+1);
/* lookup the name to see if we've seen this type before */
push_upval(L, &types_key);
lua_pushvalue(L, -2);
lua_rawget(L, top+2);
assert(lua_gettop(L) == top+3);
if (lua_isnil(L, -1)) {
lua_pop(L, 1); /* pop the nil usr value */
lua_newtable(L); /* the new usr table */
/* stack layout is:
* top+1: record name
* top+2: types table
* top+3: new usr table
*/
lua_pushlightuserdata(L, &g_name_key);
lua_pushvalue(L, top+1);
lua_rawset(L, top+3); /* usr[name_key] = name */
lua_pushvalue(L, top+1);
push_ctype(L, top+3, ct);
lua_rawset(L, top+2); /* types[name] = new_ctype */
} else {
/* get the exsting declared type */
const struct ctype* prevt = (const struct ctype*) lua_touserdata(L, top+3);
if (prevt->type != ct->type) {
lua_getuservalue(L, top+3);
push_type_name(L, -1, ct);
push_type_name(L, top+3, prevt);
luaL_error(L, "type '%s' previously declared as '%s'", lua_tostring(L, -2), lua_tostring(L, -1));
}
instantiate_typedef(P, ct, prevt);
/* replace the ctype with its usr value */
lua_getuservalue(L, -1);
lua_replace(L, -2);
}
/* remove the extra name and types table */
lua_replace(L, -3);
lua_pop(L, 1);
assert(lua_gettop(L) == top + 1 && lua_istable(L, -1));
/* if a name is given then we may be at the end of the string
* eg for ffi.new('struct foo')
*/
if (!next_token(L, P, &tok)) {
return 0;
}
} else {
/* create a new unnamed record */
int num;
/* get the next unnamed number */
push_upval(L, &next_unnamed_key);
num = lua_tointeger(L, -1);
lua_pop(L, 1);
/* increment the unnamed upval */
lua_pushinteger(L, num + 1);
set_upval(L, &next_unnamed_key);
lua_newtable(L); /* the new usr table - leave on stack */
/* usr[name_key] = num */
lua_pushlightuserdata(L, &g_name_key);
lua_pushfstring(L, "%d", num);
lua_rawset(L, -3);
}
if (tok.type != TOK_OPEN_CURLY) {
/* this may just be a declaration or use of the type as an argument or
* member */
put_back(P);
return 0;
}
if (ct->is_defined) {
return luaL_error(L, "redefinition in line %d", P->line);
}
assert(lua_gettop(L) == top + 1 && lua_istable(L, -1));
if (ct->type == ENUM_TYPE) {
parse_enum(L, P, ct);
} else {
/* we do a two stage parse, where we parse the content first and build up
* the temp user table. We then iterate over that to calculate the offsets
* and fill out ct_usr. This is so we can handle out of order members
* (eg vtable) and attributes specified at the end of the struct.
*/
lua_newtable(L);
parse_struct(L, P, -1, ct);
calculate_struct_offsets(L, P, -2, ct, -1);
assert(lua_gettop(L) == top + 2 && lua_istable(L, -1));
lua_pop(L, 1);
}
assert(lua_gettop(L) == top + 1 && lua_istable(L, -1));
set_defined(L, -1, ct);
assert(lua_gettop(L) == top + 1);
return 0;
}
/* parses single or multi work built in types, and pushes it onto the stack */
static int parse_type_name(lua_State* L, struct parser* P)
{
struct token tok;
int flags = 0;
enum {
UNSIGNED = 0x01,
SIGNED = 0x02,
LONG = 0x04,
SHORT = 0x08,
INT = 0x10,
CHAR = 0x20,
LONG_LONG = 0x40,
INT8 = 0x80,
INT16 = 0x100,
INT32 = 0x200,
INT64 = 0x400,
DOUBLE = 0x800,
FLOAT = 0x1000,
COMPLEX = 0x2000,
};
require_token(L, P, &tok);
/* we have to manually decode the builtin types since they can take up
* more then one token
*/
for (;;) {
if (tok.type != TOK_TOKEN) {
break;
} else if (IS_LITERAL(tok, "unsigned")) {
flags |= UNSIGNED;
} else if (IS_LITERAL(tok, "signed")) {
flags |= SIGNED;
} else if (IS_LITERAL(tok, "short")) {
flags |= SHORT;
} else if (IS_LITERAL(tok, "char")) {
flags |= CHAR;
} else if (IS_LITERAL(tok, "long")) {
flags |= (flags & LONG) ? LONG_LONG : LONG;
} else if (IS_LITERAL(tok, "int")) {
flags |= INT;
} else if (IS_LITERAL(tok, "__int8")) {
flags |= INT8;
} else if (IS_LITERAL(tok, "__int16")) {
flags |= INT16;
} else if (IS_LITERAL(tok, "__int32")) {
flags |= INT32;
} else if (IS_LITERAL(tok, "__int64")) {
flags |= INT64;
} else if (IS_LITERAL(tok, "double")) {
flags |= DOUBLE;
} else if (IS_LITERAL(tok, "float")) {
flags |= FLOAT;
} else if (IS_LITERAL(tok, "complex") || IS_LITERAL(tok, "_Complex")) {
flags |= COMPLEX;
} else if (IS_LITERAL(tok, "register")) {
/* ignore */
} else {
break;
}
if (!next_token(L, P, &tok)) {
break;
}
}
if (flags) {
put_back(P);
}
if (flags & CHAR) {
if (flags & SIGNED) {
lua_pushliteral(L, "int8_t");
} else if (flags & UNSIGNED) {
lua_pushliteral(L, "uint8_t");
} else {
lua_pushstring(L, (((char) -1) > 0) ? "uint8_t" : "int8_t");
}
} else if (flags & INT8) {
lua_pushstring(L, (flags & UNSIGNED) ? "uint8_t" : "int8_t");
} else if (flags & INT16) {
lua_pushstring(L, (flags & UNSIGNED) ? "uint16_t" : "int16_t");
} else if (flags & INT32) {
lua_pushstring(L, (flags & UNSIGNED) ? "uint32_t" : "int32_t");
} else if (flags & (INT64 | LONG_LONG)) {
lua_pushstring(L, (flags & UNSIGNED) ? "uint64_t" : "int64_t");
} else if (flags & COMPLEX) {
if (flags & LONG) {
lua_pushliteral(L, "complex long double");
} else if (flags & FLOAT) {
lua_pushliteral(L, "complex float");
} else {
lua_pushliteral(L, "complex double");
}
} else if (flags & DOUBLE) {
if (flags & LONG) {
lua_pushliteral(L, "long double");
} else {
lua_pushliteral(L, "double");
}
} else if (flags & FLOAT) {
lua_pushliteral(L, "float");
} else if (flags & SHORT) {
#define SHORT_TYPE(u) (sizeof(short) == sizeof(int64_t) ? u "int64_t" : sizeof(short) == sizeof(int32_t) ? u "int32_t" : u "int16_t")
if (flags & UNSIGNED) {
lua_pushstring(L, SHORT_TYPE("u"));
} else {
lua_pushstring(L, SHORT_TYPE(""));
}
#undef SHORT_TYPE
} else if (flags & LONG) {
#define LONG_TYPE(u) (sizeof(long) == sizeof(int64_t) ? u "int64_t" : u "int32_t")
if (flags & UNSIGNED) {
lua_pushstring(L, LONG_TYPE("u"));
} else {
lua_pushstring(L, LONG_TYPE(""));
}
#undef LONG_TYPE
} else if (flags) {
#define INT_TYPE(u) (sizeof(int) == sizeof(int64_t) ? u "int64_t" : sizeof(int) == sizeof(int32_t) ? u "int32_t" : u "int16_t")
if (flags & UNSIGNED) {
lua_pushstring(L, INT_TYPE("u"));
} else {
lua_pushstring(L, INT_TYPE(""));
}
#undef INT_TYPE
} else {
lua_pushlstring(L, tok.str, tok.size);
}
return 0;
}
/* parse_attribute parses a token to see if it is an attribute. It may then
* parse some following tokens to decode the attribute setting the appropriate
* fields in ct. It will return 1 if the token was used (and possibly some
* more following it) or 0 if not. If the token was used, the next token must
* be retrieved using next_token/require_token.
*/
static int parse_attribute(lua_State* L, struct parser* P, struct token* tok, struct ctype* ct, struct parser* asmname)
{
if (tok->type != TOK_TOKEN) {
return 0;
} else if (asmname && (IS_LITERAL(*tok, "__asm__") || IS_LITERAL(*tok, "__asm"))) {
check_token(L, P, TOK_OPEN_PAREN, NULL, "unexpected token after __asm__ on line %d", P->line);
*asmname = *P;
require_token(L, P, tok);
while (tok->type == TOK_STRING) {
require_token(L, P, tok);
}
if (tok->type != TOK_CLOSE_PAREN) {
luaL_error(L, "unexpected token after __asm__ on line %d", P->line);
}
return 1;
} else if (IS_LITERAL(*tok, "__attribute__") || IS_LITERAL(*tok, "__declspec")) {
int parens = 1;
check_token(L, P, TOK_OPEN_PAREN, NULL, "expected parenthesis after __attribute__ or __declspec on line %d", P->line);
for (;;) {
require_token(L, P, tok);
if (tok->type == TOK_OPEN_PAREN) {
parens++;
} else if (tok->type == TOK_CLOSE_PAREN) {
if (--parens == 0) {
break;
}
} else if (tok->type != TOK_TOKEN) {
/* ignore unknown symbols within parentheses */
} else if (IS_LITERAL(*tok, "align") || IS_LITERAL(*tok, "aligned") || IS_LITERAL(*tok, "__aligned__")) {
unsigned align = 0;
require_token(L, P, tok);
switch (tok->type) {
case TOK_CLOSE_PAREN:
align = ALIGNED_DEFAULT;
put_back(P);
break;
case TOK_OPEN_PAREN:
require_token(L, P, tok);
if (tok->type != TOK_NUMBER) {
luaL_error(L, "expected align(#) on line %d", P->line);
}
switch (tok->integer) {
case 1: align = 0; break;
case 2: align = 1; break;
case 4: align = 3; break;
case 8: align = 7; break;
case 16: align = 15; break;
default:
luaL_error(L, "unsupported align size on line %d", P->line);
}
check_token(L, P, TOK_CLOSE_PAREN, NULL, "expected align(#) on line %d", P->line);
break;
default:
luaL_error(L, "expected align(#) on line %d", P->line);
}
/* __attribute__(aligned(#)) is only supposed to increase alignment */
ct->align_mask = max(align, ct->align_mask);
} else if (IS_LITERAL(*tok, "packed") || IS_LITERAL(*tok, "__packed__")) {
ct->align_mask = 0;
ct->is_packed = 1;
} else if (IS_LITERAL(*tok, "mode") || IS_LITERAL(*tok, "__mode__")) {
check_token(L, P, TOK_OPEN_PAREN, NULL, "expected mode(MODE) on line %d", P->line);
require_token(L, P, tok);
if (tok->type != TOK_TOKEN) {
luaL_error(L, "expected mode(MODE) on line %d", P->line);
}
if (ct->type == FLOAT_TYPE || ct->type == DOUBLE_TYPE) {
struct {char ch; float v;} af;
struct {char ch; double v;} ad;
if (IS_LITERAL(*tok, "SF") || IS_LITERAL(*tok, "__SF__")) {
ct->type = FLOAT_TYPE;
ct->base_size = sizeof(float);
ct->align_mask = ALIGNOF(af);
} else if (IS_LITERAL(*tok, "DF") || IS_LITERAL(*tok, "__DF__")) {
ct->type = DOUBLE_TYPE;
ct->base_size = sizeof(double);
ct->align_mask = ALIGNOF(ad);
} else {
luaL_error(L, "unexpected mode on line %d", P->line);
}
} else {
struct {char ch; uint16_t v;} a16;
struct {char ch; uint32_t v;} a32;
struct {char ch; uint64_t v;} a64;
if (IS_LITERAL(*tok, "QI") || IS_LITERAL(*tok, "__QI__")
|| IS_LITERAL(*tok, "byte") || IS_LITERAL(*tok, "__byte__")
) {
ct->type = INT8_TYPE;
ct->base_size = sizeof(uint8_t);
ct->align_mask = 0;
} else if (IS_LITERAL(*tok, "HI") || IS_LITERAL(*tok, "__HI__")) {
ct->type = INT16_TYPE;
ct->base_size = sizeof(uint16_t);
ct->align_mask = ALIGNOF(a16);
} else if (IS_LITERAL(*tok, "SI") || IS_LITERAL(*tok, "__SI__")
#if defined ARCH_X86 || defined ARCH_ARM
|| IS_LITERAL(*tok, "word") || IS_LITERAL(*tok, "__word__")
|| IS_LITERAL(*tok, "pointer") || IS_LITERAL(*tok, "__pointer__")
#endif
) {
ct->type = INT32_TYPE;
ct->base_size = sizeof(uint32_t);
ct->align_mask = ALIGNOF(a32);
} else if (IS_LITERAL(*tok, "DI") || IS_LITERAL(*tok, "__DI__")
#if defined ARCH_X64
|| IS_LITERAL(*tok, "word") || IS_LITERAL(*tok, "__word__")
|| IS_LITERAL(*tok, "pointer") || IS_LITERAL(*tok, "__pointer__")
#endif
) {
ct->type = INT64_TYPE;
ct->base_size = sizeof(uint64_t);
ct->align_mask = ALIGNOF(a64);
} else {
luaL_error(L, "unexpected mode on line %d", P->line);
}
}
check_token(L, P, TOK_CLOSE_PAREN, NULL, "expected mode(MODE) on line %d", P->line);
} else if (IS_LITERAL(*tok, "cdecl") || IS_LITERAL(*tok, "__cdecl__")) {
ct->calling_convention = C_CALL;
} else if (IS_LITERAL(*tok, "fastcall") || IS_LITERAL(*tok, "__fastcall__")) {
ct->calling_convention = FAST_CALL;
} else if (IS_LITERAL(*tok, "stdcall") || IS_LITERAL(*tok, "__stdcall__")) {
ct->calling_convention = STD_CALL;
}
/* ignore unknown tokens within parentheses */
}
return 1;
} else if (IS_LITERAL(*tok, "__cdecl")) {
ct->calling_convention = C_CALL;
return 1;
} else if (IS_LITERAL(*tok, "__fastcall")) {
ct->calling_convention = FAST_CALL;
return 1;
} else if (IS_LITERAL(*tok, "__stdcall")) {
ct->calling_convention = STD_CALL;
return 1;
} else if (IS_LITERAL(*tok, "__extension__") || IS_LITERAL(*tok, "extern")) {
/* ignore */
return 1;
} else {
return 0;
}
}
/* parses out the base type of a type expression in a function declaration,
* struct definition, typedef etc
*
* leaves the usr value of the type on the stack
*/
int parse_type(lua_State* L, struct parser* P, struct ctype* ct)
{
struct token tok;
int top = lua_gettop(L);
memset(ct, 0, sizeof(*ct));
require_token(L, P, &tok);
/* get function attributes before the return type */
while (parse_attribute(L, P, &tok, ct, NULL)) {
require_token(L, P, &tok);
}
/* get const/volatile before the base type */
for (;;) {
if (tok.type != TOK_TOKEN) {
return luaL_error(L, "unexpected value before type name on line %d", P->line);
} else if (IS_CONST(tok)) {
ct->const_mask = 1;
require_token(L, P, &tok);
} else if (IS_VOLATILE(tok) || IS_RESTRICT(tok)) {
/* ignored for now */
require_token(L, P, &tok);
} else {
break;
}
}
/* get base type */
if (tok.type != TOK_TOKEN) {
return luaL_error(L, "unexpected value before type name on line %d", P->line);
} else if (IS_LITERAL(tok, "struct")) {
ct->type = STRUCT_TYPE;
parse_record(L, P, ct);
} else if (IS_LITERAL(tok, "union")) {
ct->type = UNION_TYPE;
parse_record(L, P, ct);
} else if (IS_LITERAL(tok, "enum")) {
ct->type = ENUM_TYPE;
parse_record(L, P, ct);
} else {
put_back(P);
/* lookup type */
push_upval(L, &types_key);
parse_type_name(L, P);
lua_rawget(L, -2);
lua_remove(L, -2);
if (lua_isnil(L, -1)) {
lua_pushlstring(L, tok.str, tok.size);
return luaL_error(L, "unknown type %s on line %d", lua_tostring(L, -1), P->line);
}
instantiate_typedef(P, ct, (const struct ctype*) lua_touserdata(L, -1));
/* we only want the usr tbl from the ctype in the types tbl */
lua_getuservalue(L, -1);
lua_replace(L, -2);
}
while (next_token(L, P, &tok)) {
if (tok.type != TOK_TOKEN) {
put_back(P);
break;
} else if (IS_CONST(tok) || IS_VOLATILE(tok)) {
/* ignore for now */
} else {
put_back(P);
break;
}
}
assert(lua_gettop(L) == top + 1 && (lua_istable(L, -1) || lua_isnil(L, -1)));
return 0;
}
enum name_type {
BOTH,
FRONT,
BACK,
};
static void append_type_name(luaL_Buffer* B, int usr, const struct ctype* ct, enum name_type type)
{
size_t i;
lua_State* L = B->L;
usr = lua_absindex(L, usr);
if (type == FRONT || type == BOTH) {
if (ct->type != FUNCTION_PTR_TYPE && (ct->const_mask & (1 << ct->pointers))) {
luaL_addstring(B, "const ");
}
if (ct->is_unsigned) {
luaL_addstring(B, "unsigned ");
}
switch (ct->type) {
case ENUM_TYPE:
luaL_addstring(B, "enum ");
goto get_name;
case STRUCT_TYPE:
luaL_addstring(B, "struct ");
goto get_name;
case UNION_TYPE:
luaL_addstring(B, "union ");
goto get_name;
get_name:
lua_pushlightuserdata(L, &g_name_key);
lua_rawget(L, usr);
luaL_addvalue(B);
break;
case FUNCTION_TYPE:
case FUNCTION_PTR_TYPE:
lua_pushlightuserdata(L, &g_front_name_key);
lua_rawget(L, usr);
luaL_addvalue(B);
break;
case VOID_TYPE:
luaL_addstring(B, "void");
break;
case BOOL_TYPE:
luaL_addstring(B, "bool");
break;
case DOUBLE_TYPE:
luaL_addstring(B, "double");
break;
case LONG_DOUBLE_TYPE:
luaL_addstring(B, "long double");
break;
case FLOAT_TYPE:
luaL_addstring(B, "float");
break;
case COMPLEX_LONG_DOUBLE_TYPE:
luaL_addstring(B, "long complex double");
break;
case COMPLEX_DOUBLE_TYPE:
luaL_addstring(B, "complex double");
break;
case COMPLEX_FLOAT_TYPE:
luaL_addstring(B, "complex float");
break;
case INT8_TYPE:
luaL_addstring(B, "char");
break;
case INT16_TYPE:
luaL_addstring(B, "short");
break;
case INT32_TYPE:
luaL_addstring(B, "int");
break;
case INT64_TYPE:
luaL_addstring(B, "long long");
break;
case INTPTR_TYPE:
if (sizeof(intptr_t) == sizeof(int32_t)) {
luaL_addstring(B, "long");
} else if (sizeof(intptr_t) == sizeof(int64_t)) {
luaL_addstring(B, "long long");
} else {
luaL_error(L, "internal error - bad type");
}
break;
default:
luaL_error(L, "internal error - bad type %d", ct->type);
}
for (i = 0; i < ct->pointers - ct->is_array; i++) {
luaL_addchar(B, '*');
if (ct->const_mask & (1 << (ct->pointers - i - 1))) {
luaL_addstring(B, " const");
}
}
}
if (type == BOTH || type == BACK) {
if (ct->is_reference) {
luaL_addstring(B, "(&)");
}
if (ct->is_variable_array && !ct->variable_size_known) {
luaL_addstring(B, "[?]");
} else if (ct->is_array) {
lua_pushfstring(L, "[%d]", (int) ct->array_size);
luaL_addvalue(B);
}
if (ct->type == FUNCTION_PTR_TYPE || ct->type == FUNCTION_TYPE) {
lua_pushlightuserdata(L, &g_back_name_key);
lua_rawget(L, usr);
luaL_addvalue(B);
}
if (ct->is_bitfield) {
lua_pushfstring(L, " : %d", (int) ct->bit_size);
luaL_addvalue(B);
}
}
}
void push_type_name(lua_State* L, int usr, const struct ctype* ct)
{
luaL_Buffer B;
usr = lua_absindex(L, usr);
luaL_buffinit(L, &B);
append_type_name(&B, usr, ct, BOTH);
luaL_pushresult(&B);
}
static void push_function_type_strings(lua_State* L, int usr, const struct ctype* ct)
{
size_t i, args;
luaL_Buffer B;
int top = lua_gettop(L);
const struct ctype* ret_ct;
int arg_ct = top+3;
int arg_usr = top+4;
int ret_usr = top+6;
usr = lua_absindex(L, usr);
/* return type */
lua_settop(L, top+4); /* room for two returns and two temp positions */
lua_rawgeti(L, usr, 0);
lua_getuservalue(L, -1);
ret_ct = (const struct ctype*) lua_touserdata(L, -2);
luaL_buffinit(L, &B);
append_type_name(&B, ret_usr, ret_ct, FRONT);
if (ret_ct->type != FUNCTION_TYPE && ret_ct->type != FUNCTION_PTR_TYPE) {
luaL_addchar(&B, ' ');
}
switch (ct->calling_convention) {
case STD_CALL:
luaL_addstring(&B, "(__stdcall *");
break;
case FAST_CALL:
luaL_addstring(&B, "(__fastcall *");
break;
case C_CALL:
luaL_addstring(&B, "(*");
break;
default:
luaL_error(L, "internal error - unknown calling convention");
}
luaL_pushresult(&B);
lua_replace(L, top+1);
luaL_buffinit(L, &B);
luaL_addstring(&B, ")(");
/* arguments */
args = lua_rawlen(L, usr);
for (i = 1; i <= args; i++) {
if (i > 1) {
luaL_addstring(&B, ", ");
}
/* note push the arg and user value below the indexes used by the buffer
* and use indexes relative to top to avoid problems due to the buffer
* system pushing a variable number of arguments onto the stack */
lua_rawgeti(L, usr, (int) i);
lua_replace(L, arg_ct);
lua_getuservalue(L, arg_ct);
lua_replace(L, arg_usr);
append_type_name(&B, arg_usr, (const struct ctype*) lua_touserdata(L, arg_ct), BOTH);
}
luaL_addstring(&B, ")");
append_type_name(&B, ret_usr, ret_ct, BACK);
luaL_pushresult(&B);
lua_replace(L, top+2);
lua_settop(L, top+2);
assert(lua_isstring(L, top+1) && lua_isstring(L, top+2));
}
/* parses from after the opening paranthesis to after the closing parenthesis */
static void parse_function_arguments(lua_State* L, struct parser* P, int ct_usr, struct ctype* ct)
{
struct token tok;
int args = 0;
int top = lua_gettop(L);
ct_usr = lua_absindex(L, ct_usr);
for (;;) {
require_token(L, P, &tok);
if (tok.type == TOK_CLOSE_PAREN) {
break;
}
if (args) {
if (tok.type != TOK_COMMA) {
luaL_error(L, "unexpected token in function argument %d on line %d", args, P->line);
}
require_token(L, P, &tok);
}
if (tok.type == TOK_VA_ARG) {
ct->has_var_arg = true;
check_token(L, P, TOK_CLOSE_PAREN, "", "unexpected token after ... in function on line %d", P->line);
break;
} else if (tok.type == TOK_TOKEN) {
struct ctype at;
put_back(P);
parse_type(L, P, &at);
parse_argument(L, P, -1, &at, NULL, NULL);
assert(lua_gettop(L) == top + 2);
/* array arguments are just treated as their base pointer type */
at.is_array = 0;
/* check for the c style int func(void) and error on other uses of arguments of type void */
if (at.type == VOID_TYPE && at.pointers == 0) {
if (args) {
luaL_error(L, "can't have argument of type void on line %d", P->line);
}
check_token(L, P, TOK_CLOSE_PAREN, "", "unexpected void in function on line %d", P->line);
lua_pop(L, 2);
break;
}
push_ctype(L, -1, &at);
lua_rawseti(L, ct_usr, ++args);
lua_pop(L, 2); /* parse_type and parse_argument at_usr */
} else {
luaL_error(L, "unexpected token in function argument %d on line %d", args+1, P->line);
}
}
assert(lua_gettop(L) == top);
}
static int max_bitfield_size(int type)
{
switch (type) {
case BOOL_TYPE:
return 1;
case INT8_TYPE:
return 8;
case INT16_TYPE:
return 16;
case INT32_TYPE:
case ENUM_TYPE:
return 32;
case INT64_TYPE:
return 64;
default:
return -1;
}
}
static struct ctype* parse_argument2(lua_State* L, struct parser* P, int ct_usr, struct ctype* ct, struct token* name, struct parser* asmname);
/* parses from after the first ( in a function declaration or function pointer
* can be one of:
* void foo(...) before ...
* void (foo)(...) before foo
* void (* <>)(...) before <> which is the inner type
*/
static struct ctype* parse_function(lua_State* L, struct parser* P, int ct_usr, struct ctype* ct, struct token* name, struct parser* asmname)
{
/* We have a function pointer or a function. The usr table will
* get replaced by the canonical one (if there is one) in
* find_canonical_usr after all the arguments and returns have
* been parsed. */
struct token tok;
int top = lua_gettop(L);
struct ctype* ret;
lua_newtable(L);
ret = push_ctype(L, ct_usr, ct);
lua_rawseti(L, -2, 0);
ct_usr = lua_gettop(L);
memset(ct, 0, sizeof(*ct));
ct->base_size = sizeof(void (*)());
ct->align_mask = min(FUNCTION_ALIGN_MASK, P->align_mask);
ct->type = FUNCTION_TYPE;
ct->is_defined = 1;
if (name->type == TOK_NIL) {
for (;;) {
require_token(L, P, &tok);
if (tok.type == TOK_STAR) {
if (ct->type == FUNCTION_TYPE) {
ct->type = FUNCTION_PTR_TYPE;
} else if (ct->pointers == POINTER_MAX) {
luaL_error(L, "maximum number of pointer derefs reached - use a struct to break up the pointers on line %d", P->line);
} else {
ct->pointers++;
ct->const_mask <<= 1;
}
} else if (parse_attribute(L, P, &tok, ct, asmname)) {
/* parse_attribute sets the appropriate fields */
} else {
/* call parse_argument to handle the inner contents
* e.g. the <> in "void (* <>) (...)". Note that the
* inner contents can itself be a function, a function
* ptr, array, etc (e.g. "void (*signal(int sig, void
* (*func)(int)))(int)" ).
*/
put_back(P);
ct = parse_argument2(L, P, ct_usr, ct, name, asmname);
break;
}
}
check_token(L, P, TOK_CLOSE_PAREN, NULL, "unexpected token in function on line %d", P->line);
check_token(L, P, TOK_OPEN_PAREN, NULL, "unexpected token in function on line %d", P->line);
}
parse_function_arguments(L, P, ct_usr, ct);
/* if we have an inner function then set the outer function ptr as its
* return type and return the inner function
* e.g. for void (* <signal(int, void (*)(int))> )(int) inner is
* surrounded by <>, return type is void (*)(int)
*/
if (lua_gettop(L) == ct_usr+1) {
lua_replace(L, ct_usr);
}
assert(lua_gettop(L) == top + 1 && lua_istable(L, -1));
return ret;
}
static struct ctype* parse_argument2(lua_State* L, struct parser* P, int ct_usr, struct ctype* ct, struct token* name, struct parser* asmname)
{
struct token tok;
int top = lua_gettop(L);
int ft_usr = 0;
luaL_checkstack(L, 10, "function too complex");
ct_usr = lua_absindex(L, ct_usr);
for (;;) {
if (!next_token(L, P, &tok)) {
/* we've reached the end of the string */
break;
} else if (tok.type == TOK_STAR) {
if (ct->pointers == POINTER_MAX) {
luaL_error(L, "maximum number of pointer derefs reached - use a struct to break up the pointers on line %d", P->line);
}
ct->pointers++;
ct->const_mask <<= 1;
/* __declspec(align(#)) may come before the type in a member */
if (!ct->is_packed) {
ct->align_mask = max(min(PTR_ALIGN_MASK, P->align_mask), ct->align_mask);
}
} else if (tok.type == TOK_REFERENCE) {
luaL_error(L, "NYI: c++ reference types");
} else if (parse_attribute(L, P, &tok, ct, asmname)) {
/* parse attribute has filled out appropriate fields in type */
} else if (tok.type == TOK_OPEN_PAREN) {
ct = parse_function(L, P, ct_usr, ct, name, asmname);
ft_usr = lua_gettop(L);
} else if (tok.type == TOK_OPEN_SQUARE) {
/* array */
if (ct->pointers == POINTER_MAX) {
luaL_error(L, "maximum number of pointer derefs reached - use a struct to break up the pointers");
}
ct->is_array = 1;
ct->pointers++;
ct->const_mask <<= 1;
require_token(L, P, &tok);
if (ct->pointers == 1 && !ct->is_defined) {
luaL_error(L, "array of undefined type on line %d", P->line);
}
if (ct->is_variable_struct || ct->is_variable_array) {
luaL_error(L, "can't have an array of a variably sized type on line %d", P->line);
}
if (tok.type == TOK_QUESTION) {
ct->is_variable_array = 1;
ct->variable_increment = (ct->pointers > 1) ? sizeof(void*) : ct->base_size;
check_token(L, P, TOK_CLOSE_SQUARE, "", "invalid character in array on line %d", P->line);
} else if (tok.type == TOK_CLOSE_SQUARE) {
ct->array_size = 0;
} else if (tok.type == TOK_TOKEN && IS_RESTRICT(tok)) {
/* odd gcc extension foo[__restrict] for arguments */
ct->array_size = 0;
check_token(L, P, TOK_CLOSE_SQUARE, "", "invalid character in array on line %d", P->line);
} else {
int64_t asize;
put_back(P);
asize = calculate_constant(L, P);
if (asize < 0) {
luaL_error(L, "array size can not be negative on line %d", P->line);
}
ct->array_size = (size_t) asize;
check_token(L, P, TOK_CLOSE_SQUARE, "", "invalid character in array on line %d", P->line);
}
} else if (tok.type == TOK_COLON) {
int64_t bsize = calculate_constant(L, P);
if (ct->pointers || bsize < 0 || bsize > max_bitfield_size(ct->type)) {
luaL_error(L, "invalid bitfield on line %d", P->line);
}
ct->is_bitfield = 1;
ct->bit_size = (unsigned) bsize;
} else if (tok.type != TOK_TOKEN) {
/* we've reached the end of the declaration */
put_back(P);
break;
} else if (IS_CONST(tok)) {
ct->const_mask |= 1;
} else if (IS_VOLATILE(tok) || IS_RESTRICT(tok)) {
/* ignored for now */
} else {
*name = tok;
}
}
assert((ft_usr == 0 && lua_gettop(L) == top) || (lua_gettop(L) == top + 1 && ft_usr == top + 1 && (lua_istable(L, -1) || lua_isnil(L, -1))));
return ct;
}
static void find_canonical_usr(lua_State* L, int ct_usr, const struct ctype *ct)
{
struct ctype rt;
int top = lua_gettop(L);
int types;
if (ct->type != FUNCTION_PTR_TYPE && ct->type != FUNCTION_TYPE) {
return;
}
luaL_checkstack(L, 10, "function too complex");
ct_usr = lua_absindex(L, ct_usr);
/* check to see if we already have the canonical usr table */
lua_pushlightuserdata(L, &g_name_key);
lua_rawget(L, ct_usr);
if (!lua_isnil(L, -1)) {
lua_pop(L, 1);
assert(top == lua_gettop(L));
return;
}
lua_pop(L, 1);
assert(top == lua_gettop(L));
/* first canonize the return type */
lua_rawgeti(L, ct_usr, 0);
rt = *(struct ctype*) lua_touserdata(L, -1);
lua_getuservalue(L, -1);
find_canonical_usr(L, -1, &rt);
push_ctype(L, -1, &rt);
lua_rawseti(L, ct_usr, 0);
lua_pop(L, 2); /* return ctype and usr */
assert(top == lua_gettop(L));
/* look up the type string in the types table */
push_upval(L, &types_key);
types = lua_gettop(L);
push_function_type_strings(L, ct_usr, ct);
lua_pushvalue(L, -2);
lua_pushvalue(L, -2);
lua_concat(L, 2);
lua_pushvalue(L, -1);
lua_rawget(L, types);
assert(lua_gettop(L) == types + 4 && types == top + 1);
/* stack: types, front, back, both, looked up value */
if (lua_isnil(L, -1)) {
lua_pop(L, 1);
lua_pushlightuserdata(L, &g_front_name_key);
lua_pushvalue(L, -4);
lua_rawset(L, ct_usr);
lua_pushlightuserdata(L, &g_back_name_key);
lua_pushvalue(L, -3);
lua_rawset(L, ct_usr);
lua_pushlightuserdata(L, &g_name_key);
lua_pushvalue(L, -2);
lua_rawset(L, ct_usr);
lua_pushvalue(L, -1);
push_ctype(L, ct_usr, ct);
lua_rawset(L, types);
} else {
lua_getuservalue(L, -1);
lua_replace(L, ct_usr);
lua_pop(L, 1);
}
lua_pop(L, 4);
assert(top == lua_gettop(L) && types == top + 1);
}
/* parses after the main base type of a typedef, function argument or
* struct/union member
* eg for const void* bar[3] the base type is void with the subtype so far of
* const, this parses the "* bar[3]" and updates the type argument
*
* ct_usr and type must be as filled out by parse_type
*
* pushes the updated user value on the top of the stack
*/
void parse_argument(lua_State* L, struct parser* P, int ct_usr, struct ctype* ct, struct token* pname, struct parser* asmname)
{
struct token tok, name;
int top = lua_gettop(L);
memset(&name, 0, sizeof(name));
parse_argument2(L, P, ct_usr, ct, &name, asmname);
for (;;) {
if (!next_token(L, P, &tok)) {
break;
} else if (parse_attribute(L, P, &tok, ct, asmname)) {
/* parse_attribute sets the appropriate fields */
} else {
put_back(P);
break;
}
}
if (lua_gettop(L) == top) {
lua_pushvalue(L, ct_usr);
}
find_canonical_usr(L, -1, ct);
if (pname) {
*pname = name;
}
}
static void parse_typedef(lua_State* L, struct parser* P)
{
struct token tok;
struct ctype base_type;
int top = lua_gettop(L);
parse_type(L, P, &base_type);
for (;;) {
struct ctype arg_type = base_type;
struct token name;
memset(&name, 0, sizeof(name));
assert(lua_gettop(L) == top + 1);
parse_argument(L, P, -1, &arg_type, &name, NULL);
assert(lua_gettop(L) == top + 2);
if (!name.size) {
luaL_error(L, "Can't have a typedef without a name on line %d", P->line);
} else if (arg_type.is_variable_array) {
luaL_error(L, "Can't typedef a variable length array on line %d", P->line);
}
push_upval(L, &types_key);
lua_pushlstring(L, name.str, name.size);
push_ctype(L, -3, &arg_type);
lua_rawset(L, -3);
lua_pop(L, 2); /* types and parse_argument usr tbl */
require_token(L, P, &tok);
if (tok.type == TOK_SEMICOLON) {
break;
} else if (tok.type != TOK_COMMA) {
luaL_error(L, "Unexpected character in typedef on line %d", P->line);
}
}
lua_pop(L, 1); /* parse_type usr tbl */
assert(lua_gettop(L) == top);
}
static bool is_hex(char ch)
{ return ('0' <= ch && ch <= '9') || ('a' <= ch && ch <= 'f') || ('A' <= ch && ch <= 'F'); }
static bool is_digit(char ch)
{ return '0' <= ch && ch <= '9'; }
static int from_hex(char ch)
{
if (ch >= 'a') {
return ch - 'a' + 10;
} else if (ch >= 'A') {
return ch - 'A' + 10;
} else {
return ch - '0';
}
}
static void push_strings(lua_State* L, struct parser* P)
{
luaL_Buffer B;
luaL_buffinit(L, &B);
for (;;) {
const char *p, *e;
char *t, *s;
struct token tok;
require_token(L, P, &tok);
if (tok.type != TOK_STRING) {
break;
}
p = tok.str;
e = p + tok.size;
t = luaL_prepbuffsize(&B, tok.size);
s = t;
while (p < e) {
if (*p == '\\') {
if (++p == e) {
luaL_error(L, "parse error in string");
}
switch (*p) {
case '\\': *(t++) = '\\'; p++; break;
case '\"': *(t++) = '\"'; p++; break;
case '\'': *(t++) = '\''; p++; break;
case 'n': *(t++) = '\n'; p++; break;
case 'r': *(t++) = '\r'; p++; break;
case 'b': *(t++) = '\b'; p++; break;
case 't': *(t++) = '\t'; p++; break;
case 'f': *(t++) = '\f'; p++; break;
case 'a': *(t++) = '\a'; p++; break;
case 'v': *(t++) = '\v'; p++; break;
case 'e': *(t++) = 0x1B; p++; break;
case 'x':
{
uint8_t u;
p++;
if (p + 2 > e || !is_hex(p[0]) || !is_hex(p[1])) {
luaL_error(L, "parse error in string");
}
u = (from_hex(p[0]) << 4) | from_hex(p[1]);
*(t++) = *(char*) &u;
p += 2;
break;
}
default:
{
uint8_t u;
const char* e2 = min(p + 3, e);
if (!is_digit(*p)) {
luaL_error(L, "parse error in string");
}
u = *p - '0';
p++;
while (is_digit(*p) && p < e2) {
u = 10*u + *p-'0';
p++;
}
*(t++) = *(char*) &u;
break;
}
}
} else {
*(t++) = *(p++);
}
}
luaL_addsize(&B, t-s);
}
luaL_pushresult(&B);
}
#define END 0
#define PRAGMA_POP 1
static int parse_root(lua_State* L, struct parser* P)
{
int top = lua_gettop(L);
struct token tok;
while (next_token(L, P, &tok)) {
/* we can have:
* struct definition
* enum definition
* union definition
* struct/enum/union declaration
* typedef
* function declaration
* pragma pack
*/
assert(lua_gettop(L) == top);
if (tok.type == TOK_SEMICOLON) {
/* empty semicolon in root continue on */
} else if (tok.type == TOK_POUND) {
check_token(L, P, TOK_TOKEN, "pragma", "unexpected pre processor directive on line %d", P->line);
check_token(L, P, TOK_TOKEN, "pack", "unexpected pre processor directive on line %d", P->line);
check_token(L, P, TOK_OPEN_PAREN, "", "invalid pack directive on line %d", P->line);
require_token(L, P, &tok);
if (tok.type == TOK_NUMBER) {
if (tok.integer != 1 && tok.integer != 2 && tok.integer != 4 && tok.integer != 8 && tok.integer != 16) {
luaL_error(L, "pack directive with invalid pack size on line %d", P->line);
}
P->align_mask = (unsigned) (tok.integer - 1);
check_token(L, P, TOK_CLOSE_PAREN, "", "invalid pack directive on line %d", P->line);
} else if (tok.type == TOK_TOKEN && IS_LITERAL(tok, "push")) {
int line = P->line;
unsigned previous_alignment = P->align_mask;
check_token(L, P, TOK_CLOSE_PAREN, "", "invalid pack directive on line %d", P->line);
if (parse_root(L, P) != PRAGMA_POP) {
luaL_error(L, "reached end of string without a pragma pop to match the push on line %d", line);
}
P->align_mask = previous_alignment;
} else if (tok.type == TOK_TOKEN && IS_LITERAL(tok, "pop")) {
check_token(L, P, TOK_CLOSE_PAREN, "", "invalid pack directive on line %d", P->line);
return PRAGMA_POP;
} else {
luaL_error(L, "invalid pack directive on line %d", P->line);
}
} else if (tok.type != TOK_TOKEN) {
return luaL_error(L, "unexpected character on line %d", P->line);
} else if (IS_LITERAL(tok, "__extension__")) {
/* ignore */
continue;
} else if (IS_LITERAL(tok, "extern")) {
/* ignore extern as data and functions can only be extern */
continue;
} else if (IS_LITERAL(tok, "typedef")) {
parse_typedef(L, P);
} else if (IS_LITERAL(tok, "static")) {
int64_t val;
require_token(L, P, &tok);
if (!IS_CONST(tok)) {
luaL_error(L, "expected 'static const int' on line %d", P->line);
}
check_token(L, P, TOK_TOKEN, "int", "expected 'static const int' on line %d", P->line);
require_token(L, P, &tok);
if (tok.type != TOK_TOKEN) {
luaL_error(L, "expected constant name after 'static const int' on line %d", P->line);
}
check_token(L, P, TOK_ASSIGN, "", "expected = after 'static const int <name>' on line %d", P->line);
val = calculate_constant(L, P);
check_token(L, P, TOK_SEMICOLON, "", "expected ; after 'static const int' definition on line %d", P->line);
push_upval(L, &constants_key);
lua_pushlstring(L, tok.str, tok.size);
lua_pushnumber(L, (int) val);
lua_rawset(L, -3);
lua_pop(L, 1); /*constants*/
} else {
/* type declaration, type definition, or function declaration */
struct ctype type;
struct token name;
struct parser asmname;
memset(&name, 0, sizeof(name));
memset(&asmname, 0, sizeof(asmname));
put_back(P);
parse_type(L, P, &type);
for (;;) {
parse_argument(L, P, -1, &type, &name, &asmname);
if (name.size) {
/* global/function declaration */
/* set asmname_tbl[name] = asmname */
if (asmname.next) {
push_upval(L, &asmname_key);
lua_pushlstring(L, name.str, name.size);
push_strings(L, &asmname);
lua_rawset(L, -3);
lua_pop(L, 1); /* asmname upval */
}
push_upval(L, &functions_key);
lua_pushlstring(L, name.str, name.size);
push_ctype(L, -3, &type);
lua_rawset(L, -3);
lua_pop(L, 1); /* functions upval */
} else {
/* type declaration/definition - already been processed */
}
lua_pop(L, 1);
require_token(L, P, &tok);
if (tok.type == TOK_SEMICOLON) {
break;
} else if (tok.type != TOK_COMMA) {
luaL_error(L, "missing semicolon on line %d", P->line);
}
}
lua_pop(L, 1);
}
}
return END;
}
int ffi_cdef(lua_State* L)
{
struct parser P;
P.line = 1;
P.prev = P.next = luaL_checkstring(L, 1);
P.align_mask = DEFAULT_ALIGN_MASK;
if (parse_root(L, &P) == PRAGMA_POP) {
luaL_error(L, "pragma pop without an associated push on line %d", P.line);
}
return 0;
}
/* calculate_constant handles operator precedence by having a number of
* recursive commands each of which computes the result at that level of
* precedence and above. calculate_constant1 is the highest precedence
*/
static int try_cast(lua_State* L)
{
struct parser* P = (struct parser*) lua_touserdata(L, 1);
struct ctype ct;
struct token name, tok;
memset(&name, 0, sizeof(name));
parse_type(L, P, &ct);
parse_argument(L, P, -1, &ct, &name, NULL);
require_token(L, P, &tok);
if (tok.type != TOK_CLOSE_PAREN || name.size) {
return luaL_error(L, "invalid cast");
}
if (ct.pointers || ct.type != INT32_TYPE) {
return luaL_error(L, "unsupported cast on line %d", P->line);
}
return 0;
}
static int64_t calculate_constant2(lua_State* L, struct parser* P, struct token* tok);
/* () */
static int64_t calculate_constant1(lua_State* L, struct parser* P, struct token* tok)
{
int64_t ret;
if (tok->type == TOK_NUMBER) {
ret = tok->integer;
next_token(L, P, tok);
return ret;
} else if (tok->type == TOK_TOKEN) {
/* look up name in constants table */
push_upval(L, &constants_key);
lua_pushlstring(L, tok->str, tok->size);
lua_rawget(L, -2);
lua_remove(L, -2); /* constants table */
if (!lua_isnumber(L, -1)) {
lua_pushlstring(L, tok->str, tok->size);
luaL_error(L, "use of undefined constant %s on line %d", lua_tostring(L, -1), P->line);
}
ret = (int64_t) lua_tonumber(L, -1);
lua_pop(L, 1);
next_token(L, P, tok);
return ret;
} else if (tok->type == TOK_OPEN_PAREN) {
struct parser before_cast = *P;
int top = lua_gettop(L);
/* see if this is a numeric cast, which we ignore */
lua_pushcfunction(L, &try_cast);
lua_pushlightuserdata(L, P);
if (!lua_pcall(L, 1, 0, 0)) {
next_token(L, P, tok);
return calculate_constant2(L, P, tok);
}
lua_settop(L, top);
*P = before_cast;
ret = calculate_constant(L, P);
require_token(L, P, tok);
if (tok->type != TOK_CLOSE_PAREN) {
luaL_error(L, "error whilst parsing constant at line %d", P->line);
}
next_token(L, P, tok);
return ret;
} else {
return luaL_error(L, "unexpected token whilst parsing constant at line %d", P->line);
}
}
/* ! and ~, unary + and -, and sizeof */
static int64_t calculate_constant2(lua_State* L, struct parser* P, struct token* tok)
{
if (tok->type == TOK_LOGICAL_NOT) {
require_token(L, P, tok);
return !calculate_constant2(L, P, tok);
} else if (tok->type == TOK_BITWISE_NOT) {
require_token(L, P, tok);
return ~calculate_constant2(L, P, tok);
} else if (tok->type == TOK_PLUS) {
require_token(L, P, tok);
return calculate_constant2(L, P, tok);
} else if (tok->type == TOK_MINUS) {
require_token(L, P, tok);
return -calculate_constant2(L, P, tok);
} else if (tok->type == TOK_TOKEN &&
(IS_LITERAL(*tok, "sizeof")
|| IS_LITERAL(*tok, "alignof")
|| IS_LITERAL(*tok, "__alignof__")
|| IS_LITERAL(*tok, "__alignof"))) {
bool issize = IS_LITERAL(*tok, "sizeof");
struct ctype type;
require_token(L, P, tok);
if (tok->type != TOK_OPEN_PAREN) {
luaL_error(L, "invalid sizeof at line %d", P->line);
}
parse_type(L, P, &type);
parse_argument(L, P, -1, &type, NULL, NULL);
lua_pop(L, 2);
require_token(L, P, tok);
if (tok->type != TOK_CLOSE_PAREN) {
luaL_error(L, "invalid sizeof at line %d", P->line);
}
next_token(L, P, tok);
return issize ? ctype_size(L, &type) : type.align_mask + 1;
} else {
return calculate_constant1(L, P, tok);
}
}
/* binary * / and % (left associative) */
static int64_t calculate_constant3(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant2(L, P, tok);
for (;;) {
if (tok->type == TOK_MULTIPLY) {
require_token(L, P, tok);
left *= calculate_constant2(L, P, tok);
} else if (tok->type == TOK_DIVIDE) {
require_token(L, P, tok);
left /= calculate_constant2(L, P, tok);
} else if (tok->type == TOK_MODULUS) {
require_token(L, P, tok);
left %= calculate_constant2(L, P, tok);
} else {
return left;
}
}
}
/* binary + and - (left associative) */
static int64_t calculate_constant4(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant3(L, P, tok);
for (;;) {
if (tok->type == TOK_PLUS) {
require_token(L, P, tok);
left += calculate_constant3(L, P, tok);
} else if (tok->type == TOK_MINUS) {
require_token(L, P, tok);
left -= calculate_constant3(L, P, tok);
} else {
return left;
}
}
}
/* binary << and >> (left associative) */
static int64_t calculate_constant5(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant4(L, P, tok);
for (;;) {
if (tok->type == TOK_LEFT_SHIFT) {
require_token(L, P, tok);
left <<= calculate_constant4(L, P, tok);
} else if (tok->type == TOK_RIGHT_SHIFT) {
require_token(L, P, tok);
left >>= calculate_constant4(L, P, tok);
} else {
return left;
}
}
}
/* binary <, <=, >, and >= (left associative) */
static int64_t calculate_constant6(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant5(L, P, tok);
for (;;) {
if (tok->type == TOK_LESS) {
require_token(L, P, tok);
left = (left < calculate_constant5(L, P, tok));
} else if (tok->type == TOK_LESS_EQUAL) {
require_token(L, P, tok);
left = (left <= calculate_constant5(L, P, tok));
} else if (tok->type == TOK_GREATER) {
require_token(L, P, tok);
left = (left > calculate_constant5(L, P, tok));
} else if (tok->type == TOK_GREATER_EQUAL) {
require_token(L, P, tok);
left = (left >= calculate_constant5(L, P, tok));
} else {
return left;
}
}
}
/* binary ==, != (left associative) */
static int64_t calculate_constant7(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant6(L, P, tok);
for (;;) {
if (tok->type == TOK_EQUAL) {
require_token(L, P, tok);
left = (left == calculate_constant6(L, P, tok));
} else if (tok->type == TOK_NOT_EQUAL) {
require_token(L, P, tok);
left = (left != calculate_constant6(L, P, tok));
} else {
return left;
}
}
}
/* binary & (left associative) */
static int64_t calculate_constant8(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant7(L, P, tok);
for (;;) {
if (tok->type == TOK_BITWISE_AND) {
require_token(L, P, tok);
left = (left & calculate_constant7(L, P, tok));
} else {
return left;
}
}
}
/* binary ^ (left associative) */
static int64_t calculate_constant9(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant8(L, P, tok);
for (;;) {
if (tok->type == TOK_BITWISE_XOR) {
require_token(L, P, tok);
left = (left ^ calculate_constant8(L, P, tok));
} else {
return left;
}
}
}
/* binary | (left associative) */
static int64_t calculate_constant10(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant9(L, P, tok);
for (;;) {
if (tok->type == TOK_BITWISE_OR) {
require_token(L, P, tok);
left = (left | calculate_constant9(L, P, tok));
} else {
return left;
}
}
}
/* binary && (left associative) */
static int64_t calculate_constant11(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant10(L, P, tok);
for (;;) {
if (tok->type == TOK_LOGICAL_AND) {
require_token(L, P, tok);
left = (left && calculate_constant10(L, P, tok));
} else {
return left;
}
}
}
/* binary || (left associative) */
static int64_t calculate_constant12(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant11(L, P, tok);
for (;;) {
if (tok->type == TOK_LOGICAL_OR) {
require_token(L, P, tok);
left = (left || calculate_constant11(L, P, tok));
} else {
return left;
}
}
}
/* ternary ?: (right associative) */
static int64_t calculate_constant13(lua_State* L, struct parser* P, struct token* tok)
{
int64_t left = calculate_constant12(L, P, tok);
if (tok->type == TOK_QUESTION) {
int64_t middle, right;
require_token(L, P, tok);
middle = calculate_constant13(L, P, tok);
if (tok->type != TOK_COLON) {
luaL_error(L, "invalid ternery (? :) in constant on line %d", P->line);
}
require_token(L, P, tok);
right = calculate_constant13(L, P, tok);
return left ? middle : right;
} else {
return left;
}
}
int64_t calculate_constant(lua_State* L, struct parser* P)
{
struct token tok;
int64_t ret;
require_token(L, P, &tok);
ret = calculate_constant13(L, P, &tok);
if (tok.type != TOK_NIL) {
put_back(P);
}
return ret;
}