mirror of
https://github.com/lua/lua
synced 2024-11-22 12:51:30 +03:00
1875 lines
55 KiB
C
1875 lines
55 KiB
C
/*
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** $Id: lstrlib.c $
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** Standard library for string operations and pattern-matching
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** See Copyright Notice in lua.h
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*/
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#define lstrlib_c
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#define LUA_LIB
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#include "lprefix.h"
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#include <ctype.h>
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#include <float.h>
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#include <limits.h>
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#include <locale.h>
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#include <math.h>
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#include <stddef.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "lua.h"
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#include "lauxlib.h"
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#include "lualib.h"
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/*
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** maximum number of captures that a pattern can do during
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** pattern-matching. This limit is arbitrary, but must fit in
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** an unsigned char.
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*/
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#if !defined(LUA_MAXCAPTURES)
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#define LUA_MAXCAPTURES 32
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#endif
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/* macro to 'unsign' a character */
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#define uchar(c) ((unsigned char)(c))
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/*
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** Some sizes are better limited to fit in 'int', but must also fit in
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** 'size_t'. (We assume that 'lua_Integer' cannot be smaller than 'int'.)
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*/
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#define MAX_SIZET ((size_t)(~(size_t)0))
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#define MAXSIZE \
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(sizeof(size_t) < sizeof(int) ? MAX_SIZET : (size_t)(INT_MAX))
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static int str_len (lua_State *L) {
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size_t l;
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luaL_checklstring(L, 1, &l);
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lua_pushinteger(L, (lua_Integer)l);
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return 1;
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}
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/*
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** translate a relative initial string position
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** (negative means back from end): clip result to [1, inf).
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** The length of any string in Lua must fit in a lua_Integer,
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** so there are no overflows in the casts.
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** The inverted comparison avoids a possible overflow
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** computing '-pos'.
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*/
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static size_t posrelatI (lua_Integer pos, size_t len) {
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if (pos > 0)
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return (size_t)pos;
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else if (pos == 0)
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return 1;
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else if (pos < -(lua_Integer)len) /* inverted comparison */
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return 1; /* clip to 1 */
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else return len + (size_t)pos + 1;
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}
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/*
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** Gets an optional ending string position from argument 'arg',
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** with default value 'def'.
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** Negative means back from end: clip result to [0, len]
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*/
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static size_t getendpos (lua_State *L, int arg, lua_Integer def,
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size_t len) {
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lua_Integer pos = luaL_optinteger(L, arg, def);
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if (pos > (lua_Integer)len)
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return len;
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else if (pos >= 0)
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return (size_t)pos;
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else if (pos < -(lua_Integer)len)
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return 0;
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else return len + (size_t)pos + 1;
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}
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static int str_sub (lua_State *L) {
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size_t l;
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const char *s = luaL_checklstring(L, 1, &l);
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size_t start = posrelatI(luaL_checkinteger(L, 2), l);
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size_t end = getendpos(L, 3, -1, l);
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if (start <= end)
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lua_pushlstring(L, s + start - 1, (end - start) + 1);
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else lua_pushliteral(L, "");
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return 1;
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}
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static int str_reverse (lua_State *L) {
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size_t l, i;
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luaL_Buffer b;
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const char *s = luaL_checklstring(L, 1, &l);
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char *p = luaL_buffinitsize(L, &b, l);
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for (i = 0; i < l; i++)
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p[i] = s[l - i - 1];
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luaL_pushresultsize(&b, l);
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return 1;
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}
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static int str_lower (lua_State *L) {
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size_t l;
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size_t i;
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luaL_Buffer b;
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const char *s = luaL_checklstring(L, 1, &l);
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char *p = luaL_buffinitsize(L, &b, l);
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for (i=0; i<l; i++)
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p[i] = tolower(uchar(s[i]));
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luaL_pushresultsize(&b, l);
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return 1;
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}
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static int str_upper (lua_State *L) {
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size_t l;
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size_t i;
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luaL_Buffer b;
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const char *s = luaL_checklstring(L, 1, &l);
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char *p = luaL_buffinitsize(L, &b, l);
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for (i=0; i<l; i++)
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p[i] = toupper(uchar(s[i]));
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luaL_pushresultsize(&b, l);
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return 1;
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}
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static int str_rep (lua_State *L) {
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size_t l, lsep;
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const char *s = luaL_checklstring(L, 1, &l);
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lua_Integer n = luaL_checkinteger(L, 2);
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const char *sep = luaL_optlstring(L, 3, "", &lsep);
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if (n <= 0)
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lua_pushliteral(L, "");
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else if (l_unlikely(l + lsep < l || l + lsep > MAXSIZE / n))
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return luaL_error(L, "resulting string too large");
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else {
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size_t totallen = (size_t)n * l + (size_t)(n - 1) * lsep;
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luaL_Buffer b;
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char *p = luaL_buffinitsize(L, &b, totallen);
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while (n-- > 1) { /* first n-1 copies (followed by separator) */
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memcpy(p, s, l * sizeof(char)); p += l;
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if (lsep > 0) { /* empty 'memcpy' is not that cheap */
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memcpy(p, sep, lsep * sizeof(char));
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p += lsep;
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}
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}
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memcpy(p, s, l * sizeof(char)); /* last copy (not followed by separator) */
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luaL_pushresultsize(&b, totallen);
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}
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return 1;
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}
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static int str_byte (lua_State *L) {
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size_t l;
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const char *s = luaL_checklstring(L, 1, &l);
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lua_Integer pi = luaL_optinteger(L, 2, 1);
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size_t posi = posrelatI(pi, l);
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size_t pose = getendpos(L, 3, pi, l);
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int n, i;
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if (posi > pose) return 0; /* empty interval; return no values */
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if (l_unlikely(pose - posi >= (size_t)INT_MAX)) /* arithmetic overflow? */
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return luaL_error(L, "string slice too long");
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n = (int)(pose - posi) + 1;
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luaL_checkstack(L, n, "string slice too long");
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for (i=0; i<n; i++)
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lua_pushinteger(L, uchar(s[posi+i-1]));
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return n;
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}
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static int str_char (lua_State *L) {
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int n = lua_gettop(L); /* number of arguments */
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int i;
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luaL_Buffer b;
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char *p = luaL_buffinitsize(L, &b, n);
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for (i=1; i<=n; i++) {
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lua_Unsigned c = (lua_Unsigned)luaL_checkinteger(L, i);
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luaL_argcheck(L, c <= (lua_Unsigned)UCHAR_MAX, i, "value out of range");
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p[i - 1] = uchar(c);
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}
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luaL_pushresultsize(&b, n);
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return 1;
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}
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/*
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** Buffer to store the result of 'string.dump'. It must be initialized
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** after the call to 'lua_dump', to ensure that the function is on the
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** top of the stack when 'lua_dump' is called. ('luaL_buffinit' might
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** push stuff.)
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*/
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struct str_Writer {
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int init; /* true iff buffer has been initialized */
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luaL_Buffer B;
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};
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static int writer (lua_State *L, const void *b, size_t size, void *ud) {
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struct str_Writer *state = (struct str_Writer *)ud;
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if (!state->init) {
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state->init = 1;
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luaL_buffinit(L, &state->B);
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}
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luaL_addlstring(&state->B, (const char *)b, size);
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return 0;
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}
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static int str_dump (lua_State *L) {
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struct str_Writer state;
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int strip = lua_toboolean(L, 2);
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luaL_checktype(L, 1, LUA_TFUNCTION);
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lua_settop(L, 1); /* ensure function is on the top of the stack */
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state.init = 0;
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if (l_unlikely(lua_dump(L, writer, &state, strip) != 0))
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return luaL_error(L, "unable to dump given function");
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luaL_pushresult(&state.B);
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return 1;
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}
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/*
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** {======================================================
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** METAMETHODS
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** =======================================================
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*/
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#if defined(LUA_NOCVTS2N) /* { */
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/* no coercion from strings to numbers */
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static const luaL_Reg stringmetamethods[] = {
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{"__index", NULL}, /* placeholder */
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{NULL, NULL}
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};
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#else /* }{ */
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static int tonum (lua_State *L, int arg) {
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if (lua_type(L, arg) == LUA_TNUMBER) { /* already a number? */
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lua_pushvalue(L, arg);
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return 1;
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}
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else { /* check whether it is a numerical string */
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size_t len;
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const char *s = lua_tolstring(L, arg, &len);
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return (s != NULL && lua_stringtonumber(L, s) == len + 1);
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}
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}
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static void trymt (lua_State *L, const char *mtname) {
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lua_settop(L, 2); /* back to the original arguments */
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if (l_unlikely(lua_type(L, 2) == LUA_TSTRING ||
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!luaL_getmetafield(L, 2, mtname)))
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luaL_error(L, "attempt to %s a '%s' with a '%s'", mtname + 2,
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luaL_typename(L, -2), luaL_typename(L, -1));
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lua_insert(L, -3); /* put metamethod before arguments */
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lua_call(L, 2, 1); /* call metamethod */
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}
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static int arith (lua_State *L, int op, const char *mtname) {
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if (tonum(L, 1) && tonum(L, 2))
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lua_arith(L, op); /* result will be on the top */
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else
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trymt(L, mtname);
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return 1;
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}
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static int arith_add (lua_State *L) {
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return arith(L, LUA_OPADD, "__add");
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}
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static int arith_sub (lua_State *L) {
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return arith(L, LUA_OPSUB, "__sub");
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}
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static int arith_mul (lua_State *L) {
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return arith(L, LUA_OPMUL, "__mul");
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}
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static int arith_mod (lua_State *L) {
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return arith(L, LUA_OPMOD, "__mod");
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}
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static int arith_pow (lua_State *L) {
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return arith(L, LUA_OPPOW, "__pow");
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}
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static int arith_div (lua_State *L) {
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return arith(L, LUA_OPDIV, "__div");
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}
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static int arith_idiv (lua_State *L) {
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return arith(L, LUA_OPIDIV, "__idiv");
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}
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static int arith_unm (lua_State *L) {
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return arith(L, LUA_OPUNM, "__unm");
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}
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static const luaL_Reg stringmetamethods[] = {
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{"__add", arith_add},
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{"__sub", arith_sub},
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{"__mul", arith_mul},
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{"__mod", arith_mod},
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{"__pow", arith_pow},
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{"__div", arith_div},
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{"__idiv", arith_idiv},
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{"__unm", arith_unm},
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{"__index", NULL}, /* placeholder */
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{NULL, NULL}
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};
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#endif /* } */
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/* }====================================================== */
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/*
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** {======================================================
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** PATTERN MATCHING
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** =======================================================
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*/
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#define CAP_UNFINISHED (-1)
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#define CAP_POSITION (-2)
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typedef struct MatchState {
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const char *src_init; /* init of source string */
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const char *src_end; /* end ('\0') of source string */
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const char *p_end; /* end ('\0') of pattern */
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lua_State *L;
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int matchdepth; /* control for recursive depth (to avoid C stack overflow) */
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unsigned char level; /* total number of captures (finished or unfinished) */
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struct {
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const char *init;
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ptrdiff_t len;
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} capture[LUA_MAXCAPTURES];
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} MatchState;
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/* recursive function */
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static const char *match (MatchState *ms, const char *s, const char *p);
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/* maximum recursion depth for 'match' */
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#if !defined(MAXCCALLS)
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#define MAXCCALLS 200
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#endif
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#define L_ESC '%'
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#define SPECIALS "^$*+?.([%-"
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static int check_capture (MatchState *ms, int l) {
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l -= '1';
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if (l_unlikely(l < 0 || l >= ms->level ||
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ms->capture[l].len == CAP_UNFINISHED))
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return luaL_error(ms->L, "invalid capture index %%%d", l + 1);
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return l;
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}
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static int capture_to_close (MatchState *ms) {
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int level = ms->level;
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for (level--; level>=0; level--)
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if (ms->capture[level].len == CAP_UNFINISHED) return level;
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return luaL_error(ms->L, "invalid pattern capture");
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}
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static const char *classend (MatchState *ms, const char *p) {
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switch (*p++) {
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case L_ESC: {
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if (l_unlikely(p == ms->p_end))
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luaL_error(ms->L, "malformed pattern (ends with '%%')");
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return p+1;
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}
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case '[': {
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if (*p == '^') p++;
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do { /* look for a ']' */
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if (l_unlikely(p == ms->p_end))
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luaL_error(ms->L, "malformed pattern (missing ']')");
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if (*(p++) == L_ESC && p < ms->p_end)
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p++; /* skip escapes (e.g. '%]') */
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} while (*p != ']');
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return p+1;
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}
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default: {
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return p;
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}
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}
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}
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static int match_class (int c, int cl) {
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int res;
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switch (tolower(cl)) {
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case 'a' : res = isalpha(c); break;
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case 'c' : res = iscntrl(c); break;
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case 'd' : res = isdigit(c); break;
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case 'g' : res = isgraph(c); break;
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case 'l' : res = islower(c); break;
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case 'p' : res = ispunct(c); break;
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case 's' : res = isspace(c); break;
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case 'u' : res = isupper(c); break;
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case 'w' : res = isalnum(c); break;
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case 'x' : res = isxdigit(c); break;
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case 'z' : res = (c == 0); break; /* deprecated option */
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default: return (cl == c);
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}
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return (islower(cl) ? res : !res);
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}
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static int matchbracketclass (int c, const char *p, const char *ec) {
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int sig = 1;
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if (*(p+1) == '^') {
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sig = 0;
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p++; /* skip the '^' */
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}
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while (++p < ec) {
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if (*p == L_ESC) {
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p++;
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if (match_class(c, uchar(*p)))
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return sig;
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}
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else if ((*(p+1) == '-') && (p+2 < ec)) {
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p+=2;
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if (uchar(*(p-2)) <= c && c <= uchar(*p))
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return sig;
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}
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else if (uchar(*p) == c) return sig;
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}
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return !sig;
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}
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static int singlematch (MatchState *ms, const char *s, const char *p,
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const char *ep) {
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if (s >= ms->src_end)
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return 0;
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else {
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int c = uchar(*s);
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switch (*p) {
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case '.': return 1; /* matches any char */
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case L_ESC: return match_class(c, uchar(*(p+1)));
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case '[': return matchbracketclass(c, p, ep-1);
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default: return (uchar(*p) == c);
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}
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}
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}
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static const char *matchbalance (MatchState *ms, const char *s,
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const char *p) {
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if (l_unlikely(p >= ms->p_end - 1))
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luaL_error(ms->L, "malformed pattern (missing arguments to '%%b')");
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if (*s != *p) return NULL;
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else {
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int b = *p;
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int e = *(p+1);
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int cont = 1;
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while (++s < ms->src_end) {
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if (*s == e) {
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if (--cont == 0) return s+1;
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}
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else if (*s == b) cont++;
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}
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}
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return NULL; /* string ends out of balance */
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}
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static const char *max_expand (MatchState *ms, const char *s,
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const char *p, const char *ep) {
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ptrdiff_t i = 0; /* counts maximum expand for item */
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while (singlematch(ms, s + i, p, ep))
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i++;
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/* keeps trying to match with the maximum repetitions */
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while (i>=0) {
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const char *res = match(ms, (s+i), ep+1);
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if (res) return res;
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i--; /* else didn't match; reduce 1 repetition to try again */
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}
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return NULL;
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}
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static const char *min_expand (MatchState *ms, const char *s,
|
|
const char *p, const char *ep) {
|
|
for (;;) {
|
|
const char *res = match(ms, s, ep+1);
|
|
if (res != NULL)
|
|
return res;
|
|
else if (singlematch(ms, s, p, ep))
|
|
s++; /* try with one more repetition */
|
|
else return NULL;
|
|
}
|
|
}
|
|
|
|
|
|
static const char *start_capture (MatchState *ms, const char *s,
|
|
const char *p, int what) {
|
|
const char *res;
|
|
int level = ms->level;
|
|
if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
|
|
ms->capture[level].init = s;
|
|
ms->capture[level].len = what;
|
|
ms->level = level+1;
|
|
if ((res=match(ms, s, p)) == NULL) /* match failed? */
|
|
ms->level--; /* undo capture */
|
|
return res;
|
|
}
|
|
|
|
|
|
static const char *end_capture (MatchState *ms, const char *s,
|
|
const char *p) {
|
|
int l = capture_to_close(ms);
|
|
const char *res;
|
|
ms->capture[l].len = s - ms->capture[l].init; /* close capture */
|
|
if ((res = match(ms, s, p)) == NULL) /* match failed? */
|
|
ms->capture[l].len = CAP_UNFINISHED; /* undo capture */
|
|
return res;
|
|
}
|
|
|
|
|
|
static const char *match_capture (MatchState *ms, const char *s, int l) {
|
|
size_t len;
|
|
l = check_capture(ms, l);
|
|
len = ms->capture[l].len;
|
|
if ((size_t)(ms->src_end-s) >= len &&
|
|
memcmp(ms->capture[l].init, s, len) == 0)
|
|
return s+len;
|
|
else return NULL;
|
|
}
|
|
|
|
|
|
static const char *match (MatchState *ms, const char *s, const char *p) {
|
|
if (l_unlikely(ms->matchdepth-- == 0))
|
|
luaL_error(ms->L, "pattern too complex");
|
|
init: /* using goto to optimize tail recursion */
|
|
if (p != ms->p_end) { /* end of pattern? */
|
|
switch (*p) {
|
|
case '(': { /* start capture */
|
|
if (*(p + 1) == ')') /* position capture? */
|
|
s = start_capture(ms, s, p + 2, CAP_POSITION);
|
|
else
|
|
s = start_capture(ms, s, p + 1, CAP_UNFINISHED);
|
|
break;
|
|
}
|
|
case ')': { /* end capture */
|
|
s = end_capture(ms, s, p + 1);
|
|
break;
|
|
}
|
|
case '$': {
|
|
if ((p + 1) != ms->p_end) /* is the '$' the last char in pattern? */
|
|
goto dflt; /* no; go to default */
|
|
s = (s == ms->src_end) ? s : NULL; /* check end of string */
|
|
break;
|
|
}
|
|
case L_ESC: { /* escaped sequences not in the format class[*+?-]? */
|
|
switch (*(p + 1)) {
|
|
case 'b': { /* balanced string? */
|
|
s = matchbalance(ms, s, p + 2);
|
|
if (s != NULL) {
|
|
p += 4; goto init; /* return match(ms, s, p + 4); */
|
|
} /* else fail (s == NULL) */
|
|
break;
|
|
}
|
|
case 'f': { /* frontier? */
|
|
const char *ep; char previous;
|
|
p += 2;
|
|
if (l_unlikely(*p != '['))
|
|
luaL_error(ms->L, "missing '[' after '%%f' in pattern");
|
|
ep = classend(ms, p); /* points to what is next */
|
|
previous = (s == ms->src_init) ? '\0' : *(s - 1);
|
|
if (!matchbracketclass(uchar(previous), p, ep - 1) &&
|
|
matchbracketclass(uchar(*s), p, ep - 1)) {
|
|
p = ep; goto init; /* return match(ms, s, ep); */
|
|
}
|
|
s = NULL; /* match failed */
|
|
break;
|
|
}
|
|
case '0': case '1': case '2': case '3':
|
|
case '4': case '5': case '6': case '7':
|
|
case '8': case '9': { /* capture results (%0-%9)? */
|
|
s = match_capture(ms, s, uchar(*(p + 1)));
|
|
if (s != NULL) {
|
|
p += 2; goto init; /* return match(ms, s, p + 2) */
|
|
}
|
|
break;
|
|
}
|
|
default: goto dflt;
|
|
}
|
|
break;
|
|
}
|
|
default: dflt: { /* pattern class plus optional suffix */
|
|
const char *ep = classend(ms, p); /* points to optional suffix */
|
|
/* does not match at least once? */
|
|
if (!singlematch(ms, s, p, ep)) {
|
|
if (*ep == '*' || *ep == '?' || *ep == '-') { /* accept empty? */
|
|
p = ep + 1; goto init; /* return match(ms, s, ep + 1); */
|
|
}
|
|
else /* '+' or no suffix */
|
|
s = NULL; /* fail */
|
|
}
|
|
else { /* matched once */
|
|
switch (*ep) { /* handle optional suffix */
|
|
case '?': { /* optional */
|
|
const char *res;
|
|
if ((res = match(ms, s + 1, ep + 1)) != NULL)
|
|
s = res;
|
|
else {
|
|
p = ep + 1; goto init; /* else return match(ms, s, ep + 1); */
|
|
}
|
|
break;
|
|
}
|
|
case '+': /* 1 or more repetitions */
|
|
s++; /* 1 match already done */
|
|
/* FALLTHROUGH */
|
|
case '*': /* 0 or more repetitions */
|
|
s = max_expand(ms, s, p, ep);
|
|
break;
|
|
case '-': /* 0 or more repetitions (minimum) */
|
|
s = min_expand(ms, s, p, ep);
|
|
break;
|
|
default: /* no suffix */
|
|
s++; p = ep; goto init; /* return match(ms, s + 1, ep); */
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
ms->matchdepth++;
|
|
return s;
|
|
}
|
|
|
|
|
|
|
|
static const char *lmemfind (const char *s1, size_t l1,
|
|
const char *s2, size_t l2) {
|
|
if (l2 == 0) return s1; /* empty strings are everywhere */
|
|
else if (l2 > l1) return NULL; /* avoids a negative 'l1' */
|
|
else {
|
|
const char *init; /* to search for a '*s2' inside 's1' */
|
|
l2--; /* 1st char will be checked by 'memchr' */
|
|
l1 = l1-l2; /* 's2' cannot be found after that */
|
|
while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
|
|
init++; /* 1st char is already checked */
|
|
if (memcmp(init, s2+1, l2) == 0)
|
|
return init-1;
|
|
else { /* correct 'l1' and 's1' to try again */
|
|
l1 -= init-s1;
|
|
s1 = init;
|
|
}
|
|
}
|
|
return NULL; /* not found */
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** get information about the i-th capture. If there are no captures
|
|
** and 'i==0', return information about the whole match, which
|
|
** is the range 's'..'e'. If the capture is a string, return
|
|
** its length and put its address in '*cap'. If it is an integer
|
|
** (a position), push it on the stack and return CAP_POSITION.
|
|
*/
|
|
static size_t get_onecapture (MatchState *ms, int i, const char *s,
|
|
const char *e, const char **cap) {
|
|
if (i >= ms->level) {
|
|
if (l_unlikely(i != 0))
|
|
luaL_error(ms->L, "invalid capture index %%%d", i + 1);
|
|
*cap = s;
|
|
return e - s;
|
|
}
|
|
else {
|
|
ptrdiff_t capl = ms->capture[i].len;
|
|
*cap = ms->capture[i].init;
|
|
if (l_unlikely(capl == CAP_UNFINISHED))
|
|
luaL_error(ms->L, "unfinished capture");
|
|
else if (capl == CAP_POSITION)
|
|
lua_pushinteger(ms->L, (ms->capture[i].init - ms->src_init) + 1);
|
|
return capl;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Push the i-th capture on the stack.
|
|
*/
|
|
static void push_onecapture (MatchState *ms, int i, const char *s,
|
|
const char *e) {
|
|
const char *cap;
|
|
ptrdiff_t l = get_onecapture(ms, i, s, e, &cap);
|
|
if (l != CAP_POSITION)
|
|
lua_pushlstring(ms->L, cap, l);
|
|
/* else position was already pushed */
|
|
}
|
|
|
|
|
|
static int push_captures (MatchState *ms, const char *s, const char *e) {
|
|
int i;
|
|
int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
|
|
luaL_checkstack(ms->L, nlevels, "too many captures");
|
|
for (i = 0; i < nlevels; i++)
|
|
push_onecapture(ms, i, s, e);
|
|
return nlevels; /* number of strings pushed */
|
|
}
|
|
|
|
|
|
/* check whether pattern has no special characters */
|
|
static int nospecials (const char *p, size_t l) {
|
|
size_t upto = 0;
|
|
do {
|
|
if (strpbrk(p + upto, SPECIALS))
|
|
return 0; /* pattern has a special character */
|
|
upto += strlen(p + upto) + 1; /* may have more after \0 */
|
|
} while (upto <= l);
|
|
return 1; /* no special chars found */
|
|
}
|
|
|
|
|
|
static void prepstate (MatchState *ms, lua_State *L,
|
|
const char *s, size_t ls, const char *p, size_t lp) {
|
|
ms->L = L;
|
|
ms->matchdepth = MAXCCALLS;
|
|
ms->src_init = s;
|
|
ms->src_end = s + ls;
|
|
ms->p_end = p + lp;
|
|
}
|
|
|
|
|
|
static void reprepstate (MatchState *ms) {
|
|
ms->level = 0;
|
|
lua_assert(ms->matchdepth == MAXCCALLS);
|
|
}
|
|
|
|
|
|
static int str_find_aux (lua_State *L, int find) {
|
|
size_t ls, lp;
|
|
const char *s = luaL_checklstring(L, 1, &ls);
|
|
const char *p = luaL_checklstring(L, 2, &lp);
|
|
size_t init = posrelatI(luaL_optinteger(L, 3, 1), ls) - 1;
|
|
if (init > ls) { /* start after string's end? */
|
|
luaL_pushfail(L); /* cannot find anything */
|
|
return 1;
|
|
}
|
|
/* explicit request or no special characters? */
|
|
if (find && (lua_toboolean(L, 4) || nospecials(p, lp))) {
|
|
/* do a plain search */
|
|
const char *s2 = lmemfind(s + init, ls - init, p, lp);
|
|
if (s2) {
|
|
lua_pushinteger(L, (s2 - s) + 1);
|
|
lua_pushinteger(L, (s2 - s) + lp);
|
|
return 2;
|
|
}
|
|
}
|
|
else {
|
|
MatchState ms;
|
|
const char *s1 = s + init;
|
|
int anchor = (*p == '^');
|
|
if (anchor) {
|
|
p++; lp--; /* skip anchor character */
|
|
}
|
|
prepstate(&ms, L, s, ls, p, lp);
|
|
do {
|
|
const char *res;
|
|
reprepstate(&ms);
|
|
if ((res=match(&ms, s1, p)) != NULL) {
|
|
if (find) {
|
|
lua_pushinteger(L, (s1 - s) + 1); /* start */
|
|
lua_pushinteger(L, res - s); /* end */
|
|
return push_captures(&ms, NULL, 0) + 2;
|
|
}
|
|
else
|
|
return push_captures(&ms, s1, res);
|
|
}
|
|
} while (s1++ < ms.src_end && !anchor);
|
|
}
|
|
luaL_pushfail(L); /* not found */
|
|
return 1;
|
|
}
|
|
|
|
|
|
static int str_find (lua_State *L) {
|
|
return str_find_aux(L, 1);
|
|
}
|
|
|
|
|
|
static int str_match (lua_State *L) {
|
|
return str_find_aux(L, 0);
|
|
}
|
|
|
|
|
|
/* state for 'gmatch' */
|
|
typedef struct GMatchState {
|
|
const char *src; /* current position */
|
|
const char *p; /* pattern */
|
|
const char *lastmatch; /* end of last match */
|
|
MatchState ms; /* match state */
|
|
} GMatchState;
|
|
|
|
|
|
static int gmatch_aux (lua_State *L) {
|
|
GMatchState *gm = (GMatchState *)lua_touserdata(L, lua_upvalueindex(3));
|
|
const char *src;
|
|
gm->ms.L = L;
|
|
for (src = gm->src; src <= gm->ms.src_end; src++) {
|
|
const char *e;
|
|
reprepstate(&gm->ms);
|
|
if ((e = match(&gm->ms, src, gm->p)) != NULL && e != gm->lastmatch) {
|
|
gm->src = gm->lastmatch = e;
|
|
return push_captures(&gm->ms, src, e);
|
|
}
|
|
}
|
|
return 0; /* not found */
|
|
}
|
|
|
|
|
|
static int gmatch (lua_State *L) {
|
|
size_t ls, lp;
|
|
const char *s = luaL_checklstring(L, 1, &ls);
|
|
const char *p = luaL_checklstring(L, 2, &lp);
|
|
size_t init = posrelatI(luaL_optinteger(L, 3, 1), ls) - 1;
|
|
GMatchState *gm;
|
|
lua_settop(L, 2); /* keep strings on closure to avoid being collected */
|
|
gm = (GMatchState *)lua_newuserdatauv(L, sizeof(GMatchState), 0);
|
|
if (init > ls) /* start after string's end? */
|
|
init = ls + 1; /* avoid overflows in 's + init' */
|
|
prepstate(&gm->ms, L, s, ls, p, lp);
|
|
gm->src = s + init; gm->p = p; gm->lastmatch = NULL;
|
|
lua_pushcclosure(L, gmatch_aux, 3);
|
|
return 1;
|
|
}
|
|
|
|
|
|
static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
|
|
const char *e) {
|
|
size_t l;
|
|
lua_State *L = ms->L;
|
|
const char *news = lua_tolstring(L, 3, &l);
|
|
const char *p;
|
|
while ((p = (char *)memchr(news, L_ESC, l)) != NULL) {
|
|
luaL_addlstring(b, news, p - news);
|
|
p++; /* skip ESC */
|
|
if (*p == L_ESC) /* '%%' */
|
|
luaL_addchar(b, *p);
|
|
else if (*p == '0') /* '%0' */
|
|
luaL_addlstring(b, s, e - s);
|
|
else if (isdigit(uchar(*p))) { /* '%n' */
|
|
const char *cap;
|
|
ptrdiff_t resl = get_onecapture(ms, *p - '1', s, e, &cap);
|
|
if (resl == CAP_POSITION)
|
|
luaL_addvalue(b); /* add position to accumulated result */
|
|
else
|
|
luaL_addlstring(b, cap, resl);
|
|
}
|
|
else
|
|
luaL_error(L, "invalid use of '%c' in replacement string", L_ESC);
|
|
l -= p + 1 - news;
|
|
news = p + 1;
|
|
}
|
|
luaL_addlstring(b, news, l);
|
|
}
|
|
|
|
|
|
/*
|
|
** Add the replacement value to the string buffer 'b'.
|
|
** Return true if the original string was changed. (Function calls and
|
|
** table indexing resulting in nil or false do not change the subject.)
|
|
*/
|
|
static int add_value (MatchState *ms, luaL_Buffer *b, const char *s,
|
|
const char *e, int tr) {
|
|
lua_State *L = ms->L;
|
|
switch (tr) {
|
|
case LUA_TFUNCTION: { /* call the function */
|
|
int n;
|
|
lua_pushvalue(L, 3); /* push the function */
|
|
n = push_captures(ms, s, e); /* all captures as arguments */
|
|
lua_call(L, n, 1); /* call it */
|
|
break;
|
|
}
|
|
case LUA_TTABLE: { /* index the table */
|
|
push_onecapture(ms, 0, s, e); /* first capture is the index */
|
|
lua_gettable(L, 3);
|
|
break;
|
|
}
|
|
default: { /* LUA_TNUMBER or LUA_TSTRING */
|
|
add_s(ms, b, s, e); /* add value to the buffer */
|
|
return 1; /* something changed */
|
|
}
|
|
}
|
|
if (!lua_toboolean(L, -1)) { /* nil or false? */
|
|
lua_pop(L, 1); /* remove value */
|
|
luaL_addlstring(b, s, e - s); /* keep original text */
|
|
return 0; /* no changes */
|
|
}
|
|
else if (l_unlikely(!lua_isstring(L, -1)))
|
|
return luaL_error(L, "invalid replacement value (a %s)",
|
|
luaL_typename(L, -1));
|
|
else {
|
|
luaL_addvalue(b); /* add result to accumulator */
|
|
return 1; /* something changed */
|
|
}
|
|
}
|
|
|
|
|
|
static int str_gsub (lua_State *L) {
|
|
size_t srcl, lp;
|
|
const char *src = luaL_checklstring(L, 1, &srcl); /* subject */
|
|
const char *p = luaL_checklstring(L, 2, &lp); /* pattern */
|
|
const char *lastmatch = NULL; /* end of last match */
|
|
int tr = lua_type(L, 3); /* replacement type */
|
|
lua_Integer max_s = luaL_optinteger(L, 4, srcl + 1); /* max replacements */
|
|
int anchor = (*p == '^');
|
|
lua_Integer n = 0; /* replacement count */
|
|
int changed = 0; /* change flag */
|
|
MatchState ms;
|
|
luaL_Buffer b;
|
|
luaL_argexpected(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
|
|
tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
|
|
"string/function/table");
|
|
luaL_buffinit(L, &b);
|
|
if (anchor) {
|
|
p++; lp--; /* skip anchor character */
|
|
}
|
|
prepstate(&ms, L, src, srcl, p, lp);
|
|
while (n < max_s) {
|
|
const char *e;
|
|
reprepstate(&ms); /* (re)prepare state for new match */
|
|
if ((e = match(&ms, src, p)) != NULL && e != lastmatch) { /* match? */
|
|
n++;
|
|
changed = add_value(&ms, &b, src, e, tr) | changed;
|
|
src = lastmatch = e;
|
|
}
|
|
else if (src < ms.src_end) /* otherwise, skip one character */
|
|
luaL_addchar(&b, *src++);
|
|
else break; /* end of subject */
|
|
if (anchor) break;
|
|
}
|
|
if (!changed) /* no changes? */
|
|
lua_pushvalue(L, 1); /* return original string */
|
|
else { /* something changed */
|
|
luaL_addlstring(&b, src, ms.src_end-src);
|
|
luaL_pushresult(&b); /* create and return new string */
|
|
}
|
|
lua_pushinteger(L, n); /* number of substitutions */
|
|
return 2;
|
|
}
|
|
|
|
/* }====================================================== */
|
|
|
|
|
|
|
|
/*
|
|
** {======================================================
|
|
** STRING FORMAT
|
|
** =======================================================
|
|
*/
|
|
|
|
#if !defined(lua_number2strx) /* { */
|
|
|
|
/*
|
|
** Hexadecimal floating-point formatter
|
|
*/
|
|
|
|
#define SIZELENMOD (sizeof(LUA_NUMBER_FRMLEN)/sizeof(char))
|
|
|
|
|
|
/*
|
|
** Number of bits that goes into the first digit. It can be any value
|
|
** between 1 and 4; the following definition tries to align the number
|
|
** to nibble boundaries by making what is left after that first digit a
|
|
** multiple of 4.
|
|
*/
|
|
#define L_NBFD ((l_floatatt(MANT_DIG) - 1)%4 + 1)
|
|
|
|
|
|
/*
|
|
** Add integer part of 'x' to buffer and return new 'x'
|
|
*/
|
|
static lua_Number adddigit (char *buff, int n, lua_Number x) {
|
|
lua_Number dd = l_mathop(floor)(x); /* get integer part from 'x' */
|
|
int d = (int)dd;
|
|
buff[n] = (d < 10 ? d + '0' : d - 10 + 'a'); /* add to buffer */
|
|
return x - dd; /* return what is left */
|
|
}
|
|
|
|
|
|
static int num2straux (char *buff, int sz, lua_Number x) {
|
|
/* if 'inf' or 'NaN', format it like '%g' */
|
|
if (x != x || x == (lua_Number)HUGE_VAL || x == -(lua_Number)HUGE_VAL)
|
|
return l_sprintf(buff, sz, LUA_NUMBER_FMT, (LUAI_UACNUMBER)x);
|
|
else if (x == 0) { /* can be -0... */
|
|
/* create "0" or "-0" followed by exponent */
|
|
return l_sprintf(buff, sz, LUA_NUMBER_FMT "x0p+0", (LUAI_UACNUMBER)x);
|
|
}
|
|
else {
|
|
int e;
|
|
lua_Number m = l_mathop(frexp)(x, &e); /* 'x' fraction and exponent */
|
|
int n = 0; /* character count */
|
|
if (m < 0) { /* is number negative? */
|
|
buff[n++] = '-'; /* add sign */
|
|
m = -m; /* make it positive */
|
|
}
|
|
buff[n++] = '0'; buff[n++] = 'x'; /* add "0x" */
|
|
m = adddigit(buff, n++, m * (1 << L_NBFD)); /* add first digit */
|
|
e -= L_NBFD; /* this digit goes before the radix point */
|
|
if (m > 0) { /* more digits? */
|
|
buff[n++] = lua_getlocaledecpoint(); /* add radix point */
|
|
do { /* add as many digits as needed */
|
|
m = adddigit(buff, n++, m * 16);
|
|
} while (m > 0);
|
|
}
|
|
n += l_sprintf(buff + n, sz - n, "p%+d", e); /* add exponent */
|
|
lua_assert(n < sz);
|
|
return n;
|
|
}
|
|
}
|
|
|
|
|
|
static int lua_number2strx (lua_State *L, char *buff, int sz,
|
|
const char *fmt, lua_Number x) {
|
|
int n = num2straux(buff, sz, x);
|
|
if (fmt[SIZELENMOD] == 'A') {
|
|
int i;
|
|
for (i = 0; i < n; i++)
|
|
buff[i] = toupper(uchar(buff[i]));
|
|
}
|
|
else if (l_unlikely(fmt[SIZELENMOD] != 'a'))
|
|
return luaL_error(L, "modifiers for format '%%a'/'%%A' not implemented");
|
|
return n;
|
|
}
|
|
|
|
#endif /* } */
|
|
|
|
|
|
/*
|
|
** Maximum size for items formatted with '%f'. This size is produced
|
|
** by format('%.99f', -maxfloat), and is equal to 99 + 3 ('-', '.',
|
|
** and '\0') + number of decimal digits to represent maxfloat (which
|
|
** is maximum exponent + 1). (99+3+1, adding some extra, 110)
|
|
*/
|
|
#define MAX_ITEMF (110 + l_floatatt(MAX_10_EXP))
|
|
|
|
|
|
/*
|
|
** All formats except '%f' do not need that large limit. The other
|
|
** float formats use exponents, so that they fit in the 99 limit for
|
|
** significant digits; 's' for large strings and 'q' add items directly
|
|
** to the buffer; all integer formats also fit in the 99 limit. The
|
|
** worst case are floats: they may need 99 significant digits, plus
|
|
** '0x', '-', '.', 'e+XXXX', and '\0'. Adding some extra, 120.
|
|
*/
|
|
#define MAX_ITEM 120
|
|
|
|
|
|
/* valid flags in a format specification */
|
|
#if !defined(L_FMTFLAGSF)
|
|
|
|
/* valid flags for a, A, e, E, f, F, g, and G conversions */
|
|
#define L_FMTFLAGSF "-+#0 "
|
|
|
|
/* valid flags for o, x, and X conversions */
|
|
#define L_FMTFLAGSX "-#0"
|
|
|
|
/* valid flags for d and i conversions */
|
|
#define L_FMTFLAGSI "-+0 "
|
|
|
|
/* valid flags for u conversions */
|
|
#define L_FMTFLAGSU "-0"
|
|
|
|
/* valid flags for c, p, and s conversions */
|
|
#define L_FMTFLAGSC "-"
|
|
|
|
#endif
|
|
|
|
|
|
/*
|
|
** Maximum size of each format specification (such as "%-099.99d"):
|
|
** Initial '%', flags (up to 5), width (2), period, precision (2),
|
|
** length modifier (8), conversion specifier, and final '\0', plus some
|
|
** extra.
|
|
*/
|
|
#define MAX_FORMAT 32
|
|
|
|
|
|
static void addquoted (luaL_Buffer *b, const char *s, size_t len) {
|
|
luaL_addchar(b, '"');
|
|
while (len--) {
|
|
if (*s == '"' || *s == '\\' || *s == '\n') {
|
|
luaL_addchar(b, '\\');
|
|
luaL_addchar(b, *s);
|
|
}
|
|
else if (iscntrl(uchar(*s))) {
|
|
char buff[10];
|
|
if (!isdigit(uchar(*(s+1))))
|
|
l_sprintf(buff, sizeof(buff), "\\%d", (int)uchar(*s));
|
|
else
|
|
l_sprintf(buff, sizeof(buff), "\\%03d", (int)uchar(*s));
|
|
luaL_addstring(b, buff);
|
|
}
|
|
else
|
|
luaL_addchar(b, *s);
|
|
s++;
|
|
}
|
|
luaL_addchar(b, '"');
|
|
}
|
|
|
|
|
|
/*
|
|
** Serialize a floating-point number in such a way that it can be
|
|
** scanned back by Lua. Use hexadecimal format for "common" numbers
|
|
** (to preserve precision); inf, -inf, and NaN are handled separately.
|
|
** (NaN cannot be expressed as a numeral, so we write '(0/0)' for it.)
|
|
*/
|
|
static int quotefloat (lua_State *L, char *buff, lua_Number n) {
|
|
const char *s; /* for the fixed representations */
|
|
if (n == (lua_Number)HUGE_VAL) /* inf? */
|
|
s = "1e9999";
|
|
else if (n == -(lua_Number)HUGE_VAL) /* -inf? */
|
|
s = "-1e9999";
|
|
else if (n != n) /* NaN? */
|
|
s = "(0/0)";
|
|
else { /* format number as hexadecimal */
|
|
int nb = lua_number2strx(L, buff, MAX_ITEM,
|
|
"%" LUA_NUMBER_FRMLEN "a", n);
|
|
/* ensures that 'buff' string uses a dot as the radix character */
|
|
if (memchr(buff, '.', nb) == NULL) { /* no dot? */
|
|
char point = lua_getlocaledecpoint(); /* try locale point */
|
|
char *ppoint = (char *)memchr(buff, point, nb);
|
|
if (ppoint) *ppoint = '.'; /* change it to a dot */
|
|
}
|
|
return nb;
|
|
}
|
|
/* for the fixed representations */
|
|
return l_sprintf(buff, MAX_ITEM, "%s", s);
|
|
}
|
|
|
|
|
|
static void addliteral (lua_State *L, luaL_Buffer *b, int arg) {
|
|
switch (lua_type(L, arg)) {
|
|
case LUA_TSTRING: {
|
|
size_t len;
|
|
const char *s = lua_tolstring(L, arg, &len);
|
|
addquoted(b, s, len);
|
|
break;
|
|
}
|
|
case LUA_TNUMBER: {
|
|
char *buff = luaL_prepbuffsize(b, MAX_ITEM);
|
|
int nb;
|
|
if (!lua_isinteger(L, arg)) /* float? */
|
|
nb = quotefloat(L, buff, lua_tonumber(L, arg));
|
|
else { /* integers */
|
|
lua_Integer n = lua_tointeger(L, arg);
|
|
const char *format = (n == LUA_MININTEGER) /* corner case? */
|
|
? "0x%" LUA_INTEGER_FRMLEN "x" /* use hex */
|
|
: LUA_INTEGER_FMT; /* else use default format */
|
|
nb = l_sprintf(buff, MAX_ITEM, format, (LUAI_UACINT)n);
|
|
}
|
|
luaL_addsize(b, nb);
|
|
break;
|
|
}
|
|
case LUA_TNIL: case LUA_TBOOLEAN: {
|
|
luaL_tolstring(L, arg, NULL);
|
|
luaL_addvalue(b);
|
|
break;
|
|
}
|
|
default: {
|
|
luaL_argerror(L, arg, "value has no literal form");
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
static const char *get2digits (const char *s) {
|
|
if (isdigit(uchar(*s))) {
|
|
s++;
|
|
if (isdigit(uchar(*s))) s++; /* (2 digits at most) */
|
|
}
|
|
return s;
|
|
}
|
|
|
|
|
|
/*
|
|
** Check whether a conversion specification is valid. When called,
|
|
** first character in 'form' must be '%' and last character must
|
|
** be a valid conversion specifier. 'flags' are the accepted flags;
|
|
** 'precision' signals whether to accept a precision.
|
|
*/
|
|
static void checkformat (lua_State *L, const char *form, const char *flags,
|
|
int precision) {
|
|
const char *spec = form + 1; /* skip '%' */
|
|
spec += strspn(spec, flags); /* skip flags */
|
|
if (*spec != '0') { /* a width cannot start with '0' */
|
|
spec = get2digits(spec); /* skip width */
|
|
if (*spec == '.' && precision) {
|
|
spec++;
|
|
spec = get2digits(spec); /* skip precision */
|
|
}
|
|
}
|
|
if (!isalpha(uchar(*spec))) /* did not go to the end? */
|
|
luaL_error(L, "invalid conversion specification: '%s'", form);
|
|
}
|
|
|
|
|
|
/*
|
|
** Get a conversion specification and copy it to 'form'.
|
|
** Return the address of its last character.
|
|
*/
|
|
static const char *getformat (lua_State *L, const char *strfrmt,
|
|
char *form) {
|
|
/* spans flags, width, and precision ('0' is included as a flag) */
|
|
size_t len = strspn(strfrmt, L_FMTFLAGSF "123456789.");
|
|
len++; /* adds following character (should be the specifier) */
|
|
/* still needs space for '%', '\0', plus a length modifier */
|
|
if (len >= MAX_FORMAT - 10)
|
|
luaL_error(L, "invalid format (too long)");
|
|
*(form++) = '%';
|
|
memcpy(form, strfrmt, len * sizeof(char));
|
|
*(form + len) = '\0';
|
|
return strfrmt + len - 1;
|
|
}
|
|
|
|
|
|
/*
|
|
** add length modifier into formats
|
|
*/
|
|
static void addlenmod (char *form, const char *lenmod) {
|
|
size_t l = strlen(form);
|
|
size_t lm = strlen(lenmod);
|
|
char spec = form[l - 1];
|
|
strcpy(form + l - 1, lenmod);
|
|
form[l + lm - 1] = spec;
|
|
form[l + lm] = '\0';
|
|
}
|
|
|
|
|
|
static int str_format (lua_State *L) {
|
|
int top = lua_gettop(L);
|
|
int arg = 1;
|
|
size_t sfl;
|
|
const char *strfrmt = luaL_checklstring(L, arg, &sfl);
|
|
const char *strfrmt_end = strfrmt+sfl;
|
|
const char *flags;
|
|
luaL_Buffer b;
|
|
luaL_buffinit(L, &b);
|
|
while (strfrmt < strfrmt_end) {
|
|
if (*strfrmt != L_ESC)
|
|
luaL_addchar(&b, *strfrmt++);
|
|
else if (*++strfrmt == L_ESC)
|
|
luaL_addchar(&b, *strfrmt++); /* %% */
|
|
else { /* format item */
|
|
char form[MAX_FORMAT]; /* to store the format ('%...') */
|
|
int maxitem = MAX_ITEM; /* maximum length for the result */
|
|
char *buff = luaL_prepbuffsize(&b, maxitem); /* to put result */
|
|
int nb = 0; /* number of bytes in result */
|
|
if (++arg > top)
|
|
return luaL_argerror(L, arg, "no value");
|
|
strfrmt = getformat(L, strfrmt, form);
|
|
switch (*strfrmt++) {
|
|
case 'c': {
|
|
checkformat(L, form, L_FMTFLAGSC, 0);
|
|
nb = l_sprintf(buff, maxitem, form, (int)luaL_checkinteger(L, arg));
|
|
break;
|
|
}
|
|
case 'd': case 'i':
|
|
flags = L_FMTFLAGSI;
|
|
goto intcase;
|
|
case 'u':
|
|
flags = L_FMTFLAGSU;
|
|
goto intcase;
|
|
case 'o': case 'x': case 'X':
|
|
flags = L_FMTFLAGSX;
|
|
intcase: {
|
|
lua_Integer n = luaL_checkinteger(L, arg);
|
|
checkformat(L, form, flags, 1);
|
|
addlenmod(form, LUA_INTEGER_FRMLEN);
|
|
nb = l_sprintf(buff, maxitem, form, (LUAI_UACINT)n);
|
|
break;
|
|
}
|
|
case 'a': case 'A':
|
|
checkformat(L, form, L_FMTFLAGSF, 1);
|
|
addlenmod(form, LUA_NUMBER_FRMLEN);
|
|
nb = lua_number2strx(L, buff, maxitem, form,
|
|
luaL_checknumber(L, arg));
|
|
break;
|
|
case 'f':
|
|
maxitem = MAX_ITEMF; /* extra space for '%f' */
|
|
buff = luaL_prepbuffsize(&b, maxitem);
|
|
/* FALLTHROUGH */
|
|
case 'e': case 'E': case 'g': case 'G': {
|
|
lua_Number n = luaL_checknumber(L, arg);
|
|
checkformat(L, form, L_FMTFLAGSF, 1);
|
|
addlenmod(form, LUA_NUMBER_FRMLEN);
|
|
nb = l_sprintf(buff, maxitem, form, (LUAI_UACNUMBER)n);
|
|
break;
|
|
}
|
|
case 'p': {
|
|
const void *p = lua_topointer(L, arg);
|
|
checkformat(L, form, L_FMTFLAGSC, 0);
|
|
if (p == NULL) { /* avoid calling 'printf' with argument NULL */
|
|
p = "(null)"; /* result */
|
|
form[strlen(form) - 1] = 's'; /* format it as a string */
|
|
}
|
|
nb = l_sprintf(buff, maxitem, form, p);
|
|
break;
|
|
}
|
|
case 'q': {
|
|
if (form[2] != '\0') /* modifiers? */
|
|
return luaL_error(L, "specifier '%%q' cannot have modifiers");
|
|
addliteral(L, &b, arg);
|
|
break;
|
|
}
|
|
case 's': {
|
|
size_t l;
|
|
const char *s = luaL_tolstring(L, arg, &l);
|
|
if (form[2] == '\0') /* no modifiers? */
|
|
luaL_addvalue(&b); /* keep entire string */
|
|
else {
|
|
luaL_argcheck(L, l == strlen(s), arg, "string contains zeros");
|
|
checkformat(L, form, L_FMTFLAGSC, 1);
|
|
if (strchr(form, '.') == NULL && l >= 100) {
|
|
/* no precision and string is too long to be formatted */
|
|
luaL_addvalue(&b); /* keep entire string */
|
|
}
|
|
else { /* format the string into 'buff' */
|
|
nb = l_sprintf(buff, maxitem, form, s);
|
|
lua_pop(L, 1); /* remove result from 'luaL_tolstring' */
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
default: { /* also treat cases 'pnLlh' */
|
|
return luaL_error(L, "invalid conversion '%s' to 'format'", form);
|
|
}
|
|
}
|
|
lua_assert(nb < maxitem);
|
|
luaL_addsize(&b, nb);
|
|
}
|
|
}
|
|
luaL_pushresult(&b);
|
|
return 1;
|
|
}
|
|
|
|
/* }====================================================== */
|
|
|
|
|
|
/*
|
|
** {======================================================
|
|
** PACK/UNPACK
|
|
** =======================================================
|
|
*/
|
|
|
|
|
|
/* value used for padding */
|
|
#if !defined(LUAL_PACKPADBYTE)
|
|
#define LUAL_PACKPADBYTE 0x00
|
|
#endif
|
|
|
|
/* maximum size for the binary representation of an integer */
|
|
#define MAXINTSIZE 16
|
|
|
|
/* number of bits in a character */
|
|
#define NB CHAR_BIT
|
|
|
|
/* mask for one character (NB 1's) */
|
|
#define MC ((1 << NB) - 1)
|
|
|
|
/* size of a lua_Integer */
|
|
#define SZINT ((int)sizeof(lua_Integer))
|
|
|
|
|
|
/* dummy union to get native endianness */
|
|
static const union {
|
|
int dummy;
|
|
char little; /* true iff machine is little endian */
|
|
} nativeendian = {1};
|
|
|
|
|
|
/*
|
|
** information to pack/unpack stuff
|
|
*/
|
|
typedef struct Header {
|
|
lua_State *L;
|
|
int islittle;
|
|
int maxalign;
|
|
} Header;
|
|
|
|
|
|
/*
|
|
** options for pack/unpack
|
|
*/
|
|
typedef enum KOption {
|
|
Kint, /* signed integers */
|
|
Kuint, /* unsigned integers */
|
|
Kfloat, /* single-precision floating-point numbers */
|
|
Knumber, /* Lua "native" floating-point numbers */
|
|
Kdouble, /* double-precision floating-point numbers */
|
|
Kchar, /* fixed-length strings */
|
|
Kstring, /* strings with prefixed length */
|
|
Kzstr, /* zero-terminated strings */
|
|
Kpadding, /* padding */
|
|
Kpaddalign, /* padding for alignment */
|
|
Knop /* no-op (configuration or spaces) */
|
|
} KOption;
|
|
|
|
|
|
/*
|
|
** Read an integer numeral from string 'fmt' or return 'df' if
|
|
** there is no numeral
|
|
*/
|
|
static int digit (int c) { return '0' <= c && c <= '9'; }
|
|
|
|
static int getnum (const char **fmt, int df) {
|
|
if (!digit(**fmt)) /* no number? */
|
|
return df; /* return default value */
|
|
else {
|
|
int a = 0;
|
|
do {
|
|
a = a*10 + (*((*fmt)++) - '0');
|
|
} while (digit(**fmt) && a <= ((int)MAXSIZE - 9)/10);
|
|
return a;
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
** Read an integer numeral and raises an error if it is larger
|
|
** than the maximum size for integers.
|
|
*/
|
|
static int getnumlimit (Header *h, const char **fmt, int df) {
|
|
int sz = getnum(fmt, df);
|
|
if (l_unlikely(sz > MAXINTSIZE || sz <= 0))
|
|
return luaL_error(h->L, "integral size (%d) out of limits [1,%d]",
|
|
sz, MAXINTSIZE);
|
|
return sz;
|
|
}
|
|
|
|
|
|
/*
|
|
** Initialize Header
|
|
*/
|
|
static void initheader (lua_State *L, Header *h) {
|
|
h->L = L;
|
|
h->islittle = nativeendian.little;
|
|
h->maxalign = 1;
|
|
}
|
|
|
|
|
|
/*
|
|
** Read and classify next option. 'size' is filled with option's size.
|
|
*/
|
|
static KOption getoption (Header *h, const char **fmt, int *size) {
|
|
/* dummy structure to get native alignment requirements */
|
|
struct cD { char c; union { LUAI_MAXALIGN; } u; };
|
|
int opt = *((*fmt)++);
|
|
*size = 0; /* default */
|
|
switch (opt) {
|
|
case 'b': *size = sizeof(char); return Kint;
|
|
case 'B': *size = sizeof(char); return Kuint;
|
|
case 'h': *size = sizeof(short); return Kint;
|
|
case 'H': *size = sizeof(short); return Kuint;
|
|
case 'l': *size = sizeof(long); return Kint;
|
|
case 'L': *size = sizeof(long); return Kuint;
|
|
case 'j': *size = sizeof(lua_Integer); return Kint;
|
|
case 'J': *size = sizeof(lua_Integer); return Kuint;
|
|
case 'T': *size = sizeof(size_t); return Kuint;
|
|
case 'f': *size = sizeof(float); return Kfloat;
|
|
case 'n': *size = sizeof(lua_Number); return Knumber;
|
|
case 'd': *size = sizeof(double); return Kdouble;
|
|
case 'i': *size = getnumlimit(h, fmt, sizeof(int)); return Kint;
|
|
case 'I': *size = getnumlimit(h, fmt, sizeof(int)); return Kuint;
|
|
case 's': *size = getnumlimit(h, fmt, sizeof(size_t)); return Kstring;
|
|
case 'c':
|
|
*size = getnum(fmt, -1);
|
|
if (l_unlikely(*size == -1))
|
|
luaL_error(h->L, "missing size for format option 'c'");
|
|
return Kchar;
|
|
case 'z': return Kzstr;
|
|
case 'x': *size = 1; return Kpadding;
|
|
case 'X': return Kpaddalign;
|
|
case ' ': break;
|
|
case '<': h->islittle = 1; break;
|
|
case '>': h->islittle = 0; break;
|
|
case '=': h->islittle = nativeendian.little; break;
|
|
case '!': {
|
|
const int maxalign = offsetof(struct cD, u);
|
|
h->maxalign = getnumlimit(h, fmt, maxalign);
|
|
break;
|
|
}
|
|
default: luaL_error(h->L, "invalid format option '%c'", opt);
|
|
}
|
|
return Knop;
|
|
}
|
|
|
|
|
|
/*
|
|
** Read, classify, and fill other details about the next option.
|
|
** 'psize' is filled with option's size, 'notoalign' with its
|
|
** alignment requirements.
|
|
** Local variable 'size' gets the size to be aligned. (Kpadal option
|
|
** always gets its full alignment, other options are limited by
|
|
** the maximum alignment ('maxalign'). Kchar option needs no alignment
|
|
** despite its size.
|
|
*/
|
|
static KOption getdetails (Header *h, size_t totalsize,
|
|
const char **fmt, int *psize, int *ntoalign) {
|
|
KOption opt = getoption(h, fmt, psize);
|
|
int align = *psize; /* usually, alignment follows size */
|
|
if (opt == Kpaddalign) { /* 'X' gets alignment from following option */
|
|
if (**fmt == '\0' || getoption(h, fmt, &align) == Kchar || align == 0)
|
|
luaL_argerror(h->L, 1, "invalid next option for option 'X'");
|
|
}
|
|
if (align <= 1 || opt == Kchar) /* need no alignment? */
|
|
*ntoalign = 0;
|
|
else {
|
|
if (align > h->maxalign) /* enforce maximum alignment */
|
|
align = h->maxalign;
|
|
if (l_unlikely((align & (align - 1)) != 0)) /* not a power of 2? */
|
|
luaL_argerror(h->L, 1, "format asks for alignment not power of 2");
|
|
*ntoalign = (align - (int)(totalsize & (align - 1))) & (align - 1);
|
|
}
|
|
return opt;
|
|
}
|
|
|
|
|
|
/*
|
|
** Pack integer 'n' with 'size' bytes and 'islittle' endianness.
|
|
** The final 'if' handles the case when 'size' is larger than
|
|
** the size of a Lua integer, correcting the extra sign-extension
|
|
** bytes if necessary (by default they would be zeros).
|
|
*/
|
|
static void packint (luaL_Buffer *b, lua_Unsigned n,
|
|
int islittle, int size, int neg) {
|
|
char *buff = luaL_prepbuffsize(b, size);
|
|
int i;
|
|
buff[islittle ? 0 : size - 1] = (char)(n & MC); /* first byte */
|
|
for (i = 1; i < size; i++) {
|
|
n >>= NB;
|
|
buff[islittle ? i : size - 1 - i] = (char)(n & MC);
|
|
}
|
|
if (neg && size > SZINT) { /* negative number need sign extension? */
|
|
for (i = SZINT; i < size; i++) /* correct extra bytes */
|
|
buff[islittle ? i : size - 1 - i] = (char)MC;
|
|
}
|
|
luaL_addsize(b, size); /* add result to buffer */
|
|
}
|
|
|
|
|
|
/*
|
|
** Copy 'size' bytes from 'src' to 'dest', correcting endianness if
|
|
** given 'islittle' is different from native endianness.
|
|
*/
|
|
static void copywithendian (char *dest, const char *src,
|
|
int size, int islittle) {
|
|
if (islittle == nativeendian.little)
|
|
memcpy(dest, src, size);
|
|
else {
|
|
dest += size - 1;
|
|
while (size-- != 0)
|
|
*(dest--) = *(src++);
|
|
}
|
|
}
|
|
|
|
|
|
static int str_pack (lua_State *L) {
|
|
luaL_Buffer b;
|
|
Header h;
|
|
const char *fmt = luaL_checkstring(L, 1); /* format string */
|
|
int arg = 1; /* current argument to pack */
|
|
size_t totalsize = 0; /* accumulate total size of result */
|
|
initheader(L, &h);
|
|
lua_pushnil(L); /* mark to separate arguments from string buffer */
|
|
luaL_buffinit(L, &b);
|
|
while (*fmt != '\0') {
|
|
int size, ntoalign;
|
|
KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign);
|
|
totalsize += ntoalign + size;
|
|
while (ntoalign-- > 0)
|
|
luaL_addchar(&b, LUAL_PACKPADBYTE); /* fill alignment */
|
|
arg++;
|
|
switch (opt) {
|
|
case Kint: { /* signed integers */
|
|
lua_Integer n = luaL_checkinteger(L, arg);
|
|
if (size < SZINT) { /* need overflow check? */
|
|
lua_Integer lim = (lua_Integer)1 << ((size * NB) - 1);
|
|
luaL_argcheck(L, -lim <= n && n < lim, arg, "integer overflow");
|
|
}
|
|
packint(&b, (lua_Unsigned)n, h.islittle, size, (n < 0));
|
|
break;
|
|
}
|
|
case Kuint: { /* unsigned integers */
|
|
lua_Integer n = luaL_checkinteger(L, arg);
|
|
if (size < SZINT) /* need overflow check? */
|
|
luaL_argcheck(L, (lua_Unsigned)n < ((lua_Unsigned)1 << (size * NB)),
|
|
arg, "unsigned overflow");
|
|
packint(&b, (lua_Unsigned)n, h.islittle, size, 0);
|
|
break;
|
|
}
|
|
case Kfloat: { /* C float */
|
|
float f = (float)luaL_checknumber(L, arg); /* get argument */
|
|
char *buff = luaL_prepbuffsize(&b, sizeof(f));
|
|
/* move 'f' to final result, correcting endianness if needed */
|
|
copywithendian(buff, (char *)&f, sizeof(f), h.islittle);
|
|
luaL_addsize(&b, size);
|
|
break;
|
|
}
|
|
case Knumber: { /* Lua float */
|
|
lua_Number f = luaL_checknumber(L, arg); /* get argument */
|
|
char *buff = luaL_prepbuffsize(&b, sizeof(f));
|
|
/* move 'f' to final result, correcting endianness if needed */
|
|
copywithendian(buff, (char *)&f, sizeof(f), h.islittle);
|
|
luaL_addsize(&b, size);
|
|
break;
|
|
}
|
|
case Kdouble: { /* C double */
|
|
double f = (double)luaL_checknumber(L, arg); /* get argument */
|
|
char *buff = luaL_prepbuffsize(&b, sizeof(f));
|
|
/* move 'f' to final result, correcting endianness if needed */
|
|
copywithendian(buff, (char *)&f, sizeof(f), h.islittle);
|
|
luaL_addsize(&b, size);
|
|
break;
|
|
}
|
|
case Kchar: { /* fixed-size string */
|
|
size_t len;
|
|
const char *s = luaL_checklstring(L, arg, &len);
|
|
luaL_argcheck(L, len <= (size_t)size, arg,
|
|
"string longer than given size");
|
|
luaL_addlstring(&b, s, len); /* add string */
|
|
while (len++ < (size_t)size) /* pad extra space */
|
|
luaL_addchar(&b, LUAL_PACKPADBYTE);
|
|
break;
|
|
}
|
|
case Kstring: { /* strings with length count */
|
|
size_t len;
|
|
const char *s = luaL_checklstring(L, arg, &len);
|
|
luaL_argcheck(L, size >= (int)sizeof(size_t) ||
|
|
len < ((size_t)1 << (size * NB)),
|
|
arg, "string length does not fit in given size");
|
|
packint(&b, (lua_Unsigned)len, h.islittle, size, 0); /* pack length */
|
|
luaL_addlstring(&b, s, len);
|
|
totalsize += len;
|
|
break;
|
|
}
|
|
case Kzstr: { /* zero-terminated string */
|
|
size_t len;
|
|
const char *s = luaL_checklstring(L, arg, &len);
|
|
luaL_argcheck(L, strlen(s) == len, arg, "string contains zeros");
|
|
luaL_addlstring(&b, s, len);
|
|
luaL_addchar(&b, '\0'); /* add zero at the end */
|
|
totalsize += len + 1;
|
|
break;
|
|
}
|
|
case Kpadding: luaL_addchar(&b, LUAL_PACKPADBYTE); /* FALLTHROUGH */
|
|
case Kpaddalign: case Knop:
|
|
arg--; /* undo increment */
|
|
break;
|
|
}
|
|
}
|
|
luaL_pushresult(&b);
|
|
return 1;
|
|
}
|
|
|
|
|
|
static int str_packsize (lua_State *L) {
|
|
Header h;
|
|
const char *fmt = luaL_checkstring(L, 1); /* format string */
|
|
size_t totalsize = 0; /* accumulate total size of result */
|
|
initheader(L, &h);
|
|
while (*fmt != '\0') {
|
|
int size, ntoalign;
|
|
KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign);
|
|
luaL_argcheck(L, opt != Kstring && opt != Kzstr, 1,
|
|
"variable-length format");
|
|
size += ntoalign; /* total space used by option */
|
|
luaL_argcheck(L, totalsize <= MAXSIZE - size, 1,
|
|
"format result too large");
|
|
totalsize += size;
|
|
}
|
|
lua_pushinteger(L, (lua_Integer)totalsize);
|
|
return 1;
|
|
}
|
|
|
|
|
|
/*
|
|
** Unpack an integer with 'size' bytes and 'islittle' endianness.
|
|
** If size is smaller than the size of a Lua integer and integer
|
|
** is signed, must do sign extension (propagating the sign to the
|
|
** higher bits); if size is larger than the size of a Lua integer,
|
|
** it must check the unread bytes to see whether they do not cause an
|
|
** overflow.
|
|
*/
|
|
static lua_Integer unpackint (lua_State *L, const char *str,
|
|
int islittle, int size, int issigned) {
|
|
lua_Unsigned res = 0;
|
|
int i;
|
|
int limit = (size <= SZINT) ? size : SZINT;
|
|
for (i = limit - 1; i >= 0; i--) {
|
|
res <<= NB;
|
|
res |= (lua_Unsigned)(unsigned char)str[islittle ? i : size - 1 - i];
|
|
}
|
|
if (size < SZINT) { /* real size smaller than lua_Integer? */
|
|
if (issigned) { /* needs sign extension? */
|
|
lua_Unsigned mask = (lua_Unsigned)1 << (size*NB - 1);
|
|
res = ((res ^ mask) - mask); /* do sign extension */
|
|
}
|
|
}
|
|
else if (size > SZINT) { /* must check unread bytes */
|
|
int mask = (!issigned || (lua_Integer)res >= 0) ? 0 : MC;
|
|
for (i = limit; i < size; i++) {
|
|
if (l_unlikely((unsigned char)str[islittle ? i : size - 1 - i] != mask))
|
|
luaL_error(L, "%d-byte integer does not fit into Lua Integer", size);
|
|
}
|
|
}
|
|
return (lua_Integer)res;
|
|
}
|
|
|
|
|
|
static int str_unpack (lua_State *L) {
|
|
Header h;
|
|
const char *fmt = luaL_checkstring(L, 1);
|
|
size_t ld;
|
|
const char *data = luaL_checklstring(L, 2, &ld);
|
|
size_t pos = posrelatI(luaL_optinteger(L, 3, 1), ld) - 1;
|
|
int n = 0; /* number of results */
|
|
luaL_argcheck(L, pos <= ld, 3, "initial position out of string");
|
|
initheader(L, &h);
|
|
while (*fmt != '\0') {
|
|
int size, ntoalign;
|
|
KOption opt = getdetails(&h, pos, &fmt, &size, &ntoalign);
|
|
luaL_argcheck(L, (size_t)ntoalign + size <= ld - pos, 2,
|
|
"data string too short");
|
|
pos += ntoalign; /* skip alignment */
|
|
/* stack space for item + next position */
|
|
luaL_checkstack(L, 2, "too many results");
|
|
n++;
|
|
switch (opt) {
|
|
case Kint:
|
|
case Kuint: {
|
|
lua_Integer res = unpackint(L, data + pos, h.islittle, size,
|
|
(opt == Kint));
|
|
lua_pushinteger(L, res);
|
|
break;
|
|
}
|
|
case Kfloat: {
|
|
float f;
|
|
copywithendian((char *)&f, data + pos, sizeof(f), h.islittle);
|
|
lua_pushnumber(L, (lua_Number)f);
|
|
break;
|
|
}
|
|
case Knumber: {
|
|
lua_Number f;
|
|
copywithendian((char *)&f, data + pos, sizeof(f), h.islittle);
|
|
lua_pushnumber(L, f);
|
|
break;
|
|
}
|
|
case Kdouble: {
|
|
double f;
|
|
copywithendian((char *)&f, data + pos, sizeof(f), h.islittle);
|
|
lua_pushnumber(L, (lua_Number)f);
|
|
break;
|
|
}
|
|
case Kchar: {
|
|
lua_pushlstring(L, data + pos, size);
|
|
break;
|
|
}
|
|
case Kstring: {
|
|
size_t len = (size_t)unpackint(L, data + pos, h.islittle, size, 0);
|
|
luaL_argcheck(L, len <= ld - pos - size, 2, "data string too short");
|
|
lua_pushlstring(L, data + pos + size, len);
|
|
pos += len; /* skip string */
|
|
break;
|
|
}
|
|
case Kzstr: {
|
|
size_t len = strlen(data + pos);
|
|
luaL_argcheck(L, pos + len < ld, 2,
|
|
"unfinished string for format 'z'");
|
|
lua_pushlstring(L, data + pos, len);
|
|
pos += len + 1; /* skip string plus final '\0' */
|
|
break;
|
|
}
|
|
case Kpaddalign: case Kpadding: case Knop:
|
|
n--; /* undo increment */
|
|
break;
|
|
}
|
|
pos += size;
|
|
}
|
|
lua_pushinteger(L, pos + 1); /* next position */
|
|
return n + 1;
|
|
}
|
|
|
|
/* }====================================================== */
|
|
|
|
|
|
static const luaL_Reg strlib[] = {
|
|
{"byte", str_byte},
|
|
{"char", str_char},
|
|
{"dump", str_dump},
|
|
{"find", str_find},
|
|
{"format", str_format},
|
|
{"gmatch", gmatch},
|
|
{"gsub", str_gsub},
|
|
{"len", str_len},
|
|
{"lower", str_lower},
|
|
{"match", str_match},
|
|
{"rep", str_rep},
|
|
{"reverse", str_reverse},
|
|
{"sub", str_sub},
|
|
{"upper", str_upper},
|
|
{"pack", str_pack},
|
|
{"packsize", str_packsize},
|
|
{"unpack", str_unpack},
|
|
{NULL, NULL}
|
|
};
|
|
|
|
|
|
static void createmetatable (lua_State *L) {
|
|
/* table to be metatable for strings */
|
|
luaL_newlibtable(L, stringmetamethods);
|
|
luaL_setfuncs(L, stringmetamethods, 0);
|
|
lua_pushliteral(L, ""); /* dummy string */
|
|
lua_pushvalue(L, -2); /* copy table */
|
|
lua_setmetatable(L, -2); /* set table as metatable for strings */
|
|
lua_pop(L, 1); /* pop dummy string */
|
|
lua_pushvalue(L, -2); /* get string library */
|
|
lua_setfield(L, -2, "__index"); /* metatable.__index = string */
|
|
lua_pop(L, 1); /* pop metatable */
|
|
}
|
|
|
|
|
|
/*
|
|
** Open string library
|
|
*/
|
|
LUAMOD_API int luaopen_string (lua_State *L) {
|
|
luaL_newlib(L, strlib);
|
|
createmetatable(L);
|
|
return 1;
|
|
}
|
|
|