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1584 lines
46 KiB
1584 lines
46 KiB
/* |
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** $Id: lstrlib.c,v 1.254.1.1 2017/04/19 17:29:57 roberto Exp $ |
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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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|
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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 <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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/* translate a relative string position: negative means back from end */ |
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static lua_Integer posrelat (lua_Integer pos, size_t len) { |
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if (pos >= 0) return pos; |
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else if (0u - (size_t)pos > len) return 0; |
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else return (lua_Integer)len + 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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lua_Integer start = posrelat(luaL_checkinteger(L, 2), l); |
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lua_Integer end = posrelat(luaL_optinteger(L, 3, -1), l); |
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if (start < 1) start = 1; |
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if (end > (lua_Integer)l) end = l; |
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if (start <= end) |
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lua_pushlstring(L, s + start - 1, (size_t)(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) lua_pushliteral(L, ""); |
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else if (l + lsep < l || l + lsep > MAXSIZE / n) /* may overflow? */ |
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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 posi = posrelat(luaL_optinteger(L, 2, 1), l); |
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lua_Integer pose = posrelat(luaL_optinteger(L, 3, posi), l); |
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int n, i; |
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if (posi < 1) posi = 1; |
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if (pose > (lua_Integer)l) pose = l; |
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if (posi > pose) return 0; /* empty interval; return no values */ |
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if (pose - posi >= 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_Integer c = luaL_checkinteger(L, i); |
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luaL_argcheck(L, uchar(c) == c, 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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static int writer (lua_State *L, const void *b, size_t size, void *B) { |
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(void)L; |
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luaL_addlstring((luaL_Buffer *) 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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luaL_Buffer b; |
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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); |
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luaL_buffinit(L,&b); |
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if (lua_dump(L, writer, &b, strip) != 0) |
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return luaL_error(L, "unable to dump given function"); |
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luaL_pushresult(&b); |
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return 1; |
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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 < 0 || l >= ms->level || 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 (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 (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 (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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return NULL; |
|
} |
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static const char *min_expand (MatchState *ms, const char *s, |
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const char *p, const char *ep) { |
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for (;;) { |
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const char *res = match(ms, s, ep+1); |
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if (res != NULL) |
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return res; |
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else if (singlematch(ms, s, p, ep)) |
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s++; /* try with one more repetition */ |
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else return NULL; |
|
} |
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} |
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static const char *start_capture (MatchState *ms, const char *s, |
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const char *p, int what) { |
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const char *res; |
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int level = ms->level; |
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if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures"); |
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ms->capture[level].init = s; |
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ms->capture[level].len = what; |
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ms->level = level+1; |
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if ((res=match(ms, s, p)) == NULL) /* match failed? */ |
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ms->level--; /* undo capture */ |
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return res; |
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} |
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static const char *end_capture (MatchState *ms, const char *s, |
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const char *p) { |
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int l = capture_to_close(ms); |
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const char *res; |
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ms->capture[l].len = s - ms->capture[l].init; /* close capture */ |
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if ((res = match(ms, s, p)) == NULL) /* match failed? */ |
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ms->capture[l].len = CAP_UNFINISHED; /* undo capture */ |
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return res; |
|
} |
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static const char *match_capture (MatchState *ms, const char *s, int l) { |
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size_t len; |
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l = check_capture(ms, l); |
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len = ms->capture[l].len; |
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if ((size_t)(ms->src_end-s) >= len && |
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memcmp(ms->capture[l].init, s, len) == 0) |
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return s+len; |
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else return NULL; |
|
} |
|
|
|
|
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static const char *match (MatchState *ms, const char *s, const char *p) { |
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if (ms->matchdepth-- == 0) |
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luaL_error(ms->L, "pattern too complex"); |
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init: /* using goto's to optimize tail recursion */ |
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if (p != ms->p_end) { /* end of pattern? */ |
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switch (*p) { |
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case '(': { /* start capture */ |
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if (*(p + 1) == ')') /* position capture? */ |
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s = start_capture(ms, s, p + 2, CAP_POSITION); |
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else |
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s = start_capture(ms, s, p + 1, CAP_UNFINISHED); |
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break; |
|
} |
|
case ')': { /* end capture */ |
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s = end_capture(ms, s, p + 1); |
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break; |
|
} |
|
case '$': { |
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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); |
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if (s != NULL) { |
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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 (*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 */ |
|
} |
|
} |
|
|
|
|
|
static void push_onecapture (MatchState *ms, int i, const char *s, |
|
const char *e) { |
|
if (i >= ms->level) { |
|
if (i == 0) /* ms->level == 0, too */ |
|
lua_pushlstring(ms->L, s, e - s); /* add whole match */ |
|
else |
|
luaL_error(ms->L, "invalid capture index %%%d", i + 1); |
|
} |
|
else { |
|
ptrdiff_t l = ms->capture[i].len; |
|
if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture"); |
|
if (l == CAP_POSITION) |
|
lua_pushinteger(ms->L, (ms->capture[i].init - ms->src_init) + 1); |
|
else |
|
lua_pushlstring(ms->L, ms->capture[i].init, l); |
|
} |
|
} |
|
|
|
|
|
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); |
|
lua_Integer init = posrelat(luaL_optinteger(L, 3, 1), ls); |
|
if (init < 1) init = 1; |
|
else if (init > (lua_Integer)ls + 1) { /* start after string's end? */ |
|
lua_pushnil(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 - 1, ls - (size_t)init + 1, 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 - 1; |
|
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); |
|
} |
|
lua_pushnil(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); |
|
GMatchState *gm; |
|
lua_settop(L, 2); /* keep them on closure to avoid being collected */ |
|
gm = (GMatchState *)lua_newuserdata(L, sizeof(GMatchState)); |
|
prepstate(&gm->ms, L, s, ls, p, lp); |
|
gm->src = s; 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, i; |
|
lua_State *L = ms->L; |
|
const char *news = lua_tolstring(L, 3, &l); |
|
for (i = 0; i < l; i++) { |
|
if (news[i] != L_ESC) |
|
luaL_addchar(b, news[i]); |
|
else { |
|
i++; /* skip ESC */ |
|
if (!isdigit(uchar(news[i]))) { |
|
if (news[i] != L_ESC) |
|
luaL_error(L, "invalid use of '%c' in replacement string", L_ESC); |
|
luaL_addchar(b, news[i]); |
|
} |
|
else if (news[i] == '0') |
|
luaL_addlstring(b, s, e - s); |
|
else { |
|
push_onecapture(ms, news[i] - '1', s, e); |
|
luaL_tolstring(L, -1, NULL); /* if number, convert it to string */ |
|
lua_remove(L, -2); /* remove original value */ |
|
luaL_addvalue(b); /* add capture to accumulated result */ |
|
} |
|
} |
|
} |
|
} |
|
|
|
|
|
static void 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: { |
|
int n; |
|
lua_pushvalue(L, 3); |
|
n = push_captures(ms, s, e); |
|
lua_call(L, n, 1); |
|
break; |
|
} |
|
case LUA_TTABLE: { |
|
push_onecapture(ms, 0, s, e); |
|
lua_gettable(L, 3); |
|
break; |
|
} |
|
default: { /* LUA_TNUMBER or LUA_TSTRING */ |
|
add_s(ms, b, s, e); |
|
return; |
|
} |
|
} |
|
if (!lua_toboolean(L, -1)) { /* nil or false? */ |
|
lua_pop(L, 1); |
|
lua_pushlstring(L, s, e - s); /* keep original text */ |
|
} |
|
else if (!lua_isstring(L, -1)) |
|
luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1)); |
|
luaL_addvalue(b); /* add result to accumulator */ |
|
} |
|
|
|
|
|
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 */ |
|
MatchState ms; |
|
luaL_Buffer b; |
|
luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING || |
|
tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3, |
|
"string/function/table expected"); |
|
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++; |
|
add_value(&ms, &b, src, e, tr); /* add replacement to buffer */ |
|
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; |
|
} |
|
luaL_addlstring(&b, src, ms.src_end-src); |
|
luaL_pushresult(&b); |
|
lua_pushinteger(L, n); /* number of substitutions */ |
|
return 2; |
|
} |
|
|
|
/* }====================================================== */ |
|
|
|
|
|
|
|
/* |
|
** {====================================================== |
|
** STRING FORMAT |
|
** ======================================================= |
|
*/ |
|
|
|
#if !defined(lua_number2strx) /* { */ |
|
|
|
/* |
|
** Hexadecimal floating-point formatter |
|
*/ |
|
|
|
#include <math.h> |
|
|
|
#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_mathlim(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 signal */ |
|
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 (fmt[SIZELENMOD] != 'a') |
|
return luaL_error(L, "modifiers for format '%%a'/'%%A' not implemented"); |
|
return n; |
|
} |
|
|
|
#endif /* } */ |
|
|
|
|
|
/* |
|
** Maximum size of each formatted item. This maximum 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 then rounded to 120 for "extra |
|
** expenses", such as locale-dependent stuff) |
|
*/ |
|
#define MAX_ITEM (120 + l_mathlim(MAX_10_EXP)) |
|
|
|
|
|
/* valid flags in a format specification */ |
|
#define FLAGS "-+ #0" |
|
|
|
/* |
|
** maximum size of each format specification (such as "%-099.99d") |
|
*/ |
|
#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, '"'); |
|
} |
|
|
|
|
|
/* |
|
** Ensures the 'buff' string uses a dot as the radix character. |
|
*/ |
|
static void checkdp (char *buff, int nb) { |
|
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 */ |
|
} |
|
} |
|
|
|
|
|
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? */ |
|
lua_Number n = lua_tonumber(L, arg); /* write as hexa ('%a') */ |
|
nb = lua_number2strx(L, buff, MAX_ITEM, "%" LUA_NUMBER_FRMLEN "a", n); |
|
checkdp(buff, nb); /* ensure it uses a dot */ |
|
} |
|
else { /* integers */ |
|
lua_Integer n = lua_tointeger(L, arg); |
|
const char *format = (n == LUA_MININTEGER) /* corner case? */ |
|
? "0x%" LUA_INTEGER_FRMLEN "x" /* use hexa */ |
|
: 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 *scanformat (lua_State *L, const char *strfrmt, char *form) { |
|
const char *p = strfrmt; |
|
while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++; /* skip flags */ |
|
if ((size_t)(p - strfrmt) >= sizeof(FLAGS)/sizeof(char)) |
|
luaL_error(L, "invalid format (repeated flags)"); |
|
if (isdigit(uchar(*p))) p++; /* skip width */ |
|
if (isdigit(uchar(*p))) p++; /* (2 digits at most) */ |
|
if (*p == '.') { |
|
p++; |
|
if (isdigit(uchar(*p))) p++; /* skip precision */ |
|
if (isdigit(uchar(*p))) p++; /* (2 digits at most) */ |
|
} |
|
if (isdigit(uchar(*p))) |
|
luaL_error(L, "invalid format (width or precision too long)"); |
|
*(form++) = '%'; |
|
memcpy(form, strfrmt, ((p - strfrmt) + 1) * sizeof(char)); |
|
form += (p - strfrmt) + 1; |
|
*form = '\0'; |
|
return p; |
|
} |
|
|
|
|
|
/* |
|
** 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; |
|
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 ('%...') */ |
|
char *buff = luaL_prepbuffsize(&b, MAX_ITEM); /* to put formatted item */ |
|
int nb = 0; /* number of bytes in added item */ |
|
if (++arg > top) |
|
luaL_argerror(L, arg, "no value"); |
|
strfrmt = scanformat(L, strfrmt, form); |
|
switch (*strfrmt++) { |
|
case 'c': { |
|
nb = l_sprintf(buff, MAX_ITEM, form, (int)luaL_checkinteger(L, arg)); |
|
break; |
|
} |
|
case 'd': case 'i': |
|
case 'o': case 'u': case 'x': case 'X': { |
|
lua_Integer n = luaL_checkinteger(L, arg); |
|
addlenmod(form, LUA_INTEGER_FRMLEN); |
|
nb = l_sprintf(buff, MAX_ITEM, form, (LUAI_UACINT)n); |
|
break; |
|
} |
|
case 'a': case 'A': |
|
addlenmod(form, LUA_NUMBER_FRMLEN); |
|
nb = lua_number2strx(L, buff, MAX_ITEM, form, |
|
luaL_checknumber(L, arg)); |
|
break; |
|
case 'e': case 'E': case 'f': |
|
case 'g': case 'G': { |
|
lua_Number n = luaL_checknumber(L, arg); |
|
addlenmod(form, LUA_NUMBER_FRMLEN); |
|
nb = l_sprintf(buff, MAX_ITEM, form, (LUAI_UACNUMBER)n); |
|
break; |
|
} |
|
case 'q': { |
|
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"); |
|
if (!strchr(form, '.') && 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, MAX_ITEM, form, s); |
|
lua_pop(L, 1); /* remove result from 'luaL_tolstring' */ |
|
} |
|
} |
|
break; |
|
} |
|
default: { /* also treat cases 'pnLlh' */ |
|
return luaL_error(L, "invalid option '%%%c' to 'format'", |
|
*(strfrmt - 1)); |
|
} |
|
} |
|
lua_assert(nb < MAX_ITEM); |
|
luaL_addsize(&b, nb); |
|
} |
|
} |
|
luaL_pushresult(&b); |
|
return 1; |
|
} |
|
|
|
/* }====================================================== */ |
|
|
|
|
|
/* |
|
** {====================================================== |
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** PACK/UNPACK |
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** ======================================================= |
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*/ |
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/* value used for padding */ |
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#if !defined(LUAL_PACKPADBYTE) |
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#define LUAL_PACKPADBYTE 0x00 |
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#endif |
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/* maximum size for the binary representation of an integer */ |
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#define MAXINTSIZE 16 |
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/* number of bits in a character */ |
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#define NB CHAR_BIT |
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/* mask for one character (NB 1's) */ |
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#define MC ((1 << NB) - 1) |
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/* size of a lua_Integer */ |
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#define SZINT ((int)sizeof(lua_Integer)) |
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/* dummy union to get native endianness */ |
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static const union { |
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int dummy; |
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char little; /* true iff machine is little endian */ |
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} nativeendian = {1}; |
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/* dummy structure to get native alignment requirements */ |
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struct cD { |
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char c; |
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union { double d; void *p; lua_Integer i; lua_Number n; } u; |
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}; |
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#define MAXALIGN (offsetof(struct cD, u)) |
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/* |
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** Union for serializing floats |
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*/ |
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typedef union Ftypes { |
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float f; |
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double d; |
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lua_Number n; |
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char buff[5 * sizeof(lua_Number)]; /* enough for any float type */ |
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} Ftypes; |
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/* |
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** information to pack/unpack stuff |
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*/ |
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typedef struct Header { |
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lua_State *L; |
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int islittle; |
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int maxalign; |
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} Header; |
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/* |
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** options for pack/unpack |
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*/ |
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typedef enum KOption { |
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Kint, /* signed integers */ |
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Kuint, /* unsigned integers */ |
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Kfloat, /* floating-point numbers */ |
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Kchar, /* fixed-length strings */ |
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Kstring, /* strings with prefixed length */ |
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Kzstr, /* zero-terminated strings */ |
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Kpadding, /* padding */ |
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Kpaddalign, /* padding for alignment */ |
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Knop /* no-op (configuration or spaces) */ |
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} KOption; |
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/* |
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** Read an integer numeral from string 'fmt' or return 'df' if |
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** there is no numeral |
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*/ |
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static int digit (int c) { return '0' <= c && c <= '9'; } |
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static int getnum (const char **fmt, int df) { |
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if (!digit(**fmt)) /* no number? */ |
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return df; /* return default value */ |
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else { |
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int a = 0; |
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do { |
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a = a*10 + (*((*fmt)++) - '0'); |
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} while (digit(**fmt) && a <= ((int)MAXSIZE - 9)/10); |
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return a; |
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} |
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} |
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/* |
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** Read an integer numeral and raises an error if it is larger |
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** than the maximum size for integers. |
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*/ |
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static int getnumlimit (Header *h, const char **fmt, int df) { |
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int sz = getnum(fmt, df); |
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if (sz > MAXINTSIZE || sz <= 0) |
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return luaL_error(h->L, "integral size (%d) out of limits [1,%d]", |
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sz, MAXINTSIZE); |
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return sz; |
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} |
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/* |
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** Initialize Header |
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*/ |
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static void initheader (lua_State *L, Header *h) { |
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h->L = L; |
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h->islittle = nativeendian.little; |
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h->maxalign = 1; |
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} |
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/* |
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** Read and classify next option. 'size' is filled with option's size. |
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*/ |
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static KOption getoption (Header *h, const char **fmt, int *size) { |
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int opt = *((*fmt)++); |
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*size = 0; /* default */ |
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switch (opt) { |
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case 'b': *size = sizeof(char); return Kint; |
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case 'B': *size = sizeof(char); return Kuint; |
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case 'h': *size = sizeof(short); return Kint; |
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case 'H': *size = sizeof(short); return Kuint; |
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case 'l': *size = sizeof(long); return Kint; |
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case 'L': *size = sizeof(long); return Kuint; |
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case 'j': *size = sizeof(lua_Integer); return Kint; |
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case 'J': *size = sizeof(lua_Integer); return Kuint; |
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case 'T': *size = sizeof(size_t); return Kuint; |
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case 'f': *size = sizeof(float); return Kfloat; |
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case 'd': *size = sizeof(double); return Kfloat; |
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case 'n': *size = sizeof(lua_Number); return Kfloat; |
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case 'i': *size = getnumlimit(h, fmt, sizeof(int)); return Kint; |
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case 'I': *size = getnumlimit(h, fmt, sizeof(int)); return Kuint; |
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case 's': *size = getnumlimit(h, fmt, sizeof(size_t)); return Kstring; |
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case 'c': |
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*size = getnum(fmt, -1); |
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if (*size == -1) |
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luaL_error(h->L, "missing size for format option 'c'"); |
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return Kchar; |
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case 'z': return Kzstr; |
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case 'x': *size = 1; return Kpadding; |
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case 'X': return Kpaddalign; |
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case ' ': break; |
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case '<': h->islittle = 1; break; |
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case '>': h->islittle = 0; break; |
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case '=': h->islittle = nativeendian.little; break; |
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case '!': h->maxalign = getnumlimit(h, fmt, MAXALIGN); break; |
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default: luaL_error(h->L, "invalid format option '%c'", opt); |
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} |
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return Knop; |
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} |
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/* |
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** Read, classify, and fill other details about the next option. |
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** 'psize' is filled with option's size, 'notoalign' with its |
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** alignment requirements. |
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** Local variable 'size' gets the size to be aligned. (Kpadal option |
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** always gets its full alignment, other options are limited by |
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** the maximum alignment ('maxalign'). Kchar option needs no alignment |
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** despite its size. |
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*/ |
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static KOption getdetails (Header *h, size_t totalsize, |
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const char **fmt, int *psize, int *ntoalign) { |
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KOption opt = getoption(h, fmt, psize); |
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int align = *psize; /* usually, alignment follows size */ |
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if (opt == Kpaddalign) { /* 'X' gets alignment from following option */ |
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if (**fmt == '\0' || getoption(h, fmt, &align) == Kchar || align == 0) |
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luaL_argerror(h->L, 1, "invalid next option for option 'X'"); |
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} |
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if (align <= 1 || opt == Kchar) /* need no alignment? */ |
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*ntoalign = 0; |
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else { |
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if (align > h->maxalign) /* enforce maximum alignment */ |
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align = h->maxalign; |
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if ((align & (align - 1)) != 0) /* is 'align' not a power of 2? */ |
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luaL_argerror(h->L, 1, "format asks for alignment not power of 2"); |
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*ntoalign = (align - (int)(totalsize & (align - 1))) & (align - 1); |
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} |
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return opt; |
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} |
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/* |
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** Pack integer 'n' with 'size' bytes and 'islittle' endianness. |
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** The final 'if' handles the case when 'size' is larger than |
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** the size of a Lua integer, correcting the extra sign-extension |
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** bytes if necessary (by default they would be zeros). |
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*/ |
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static void packint (luaL_Buffer *b, lua_Unsigned n, |
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int islittle, int size, int neg) { |
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char *buff = luaL_prepbuffsize(b, size); |
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int i; |
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buff[islittle ? 0 : size - 1] = (char)(n & MC); /* first byte */ |
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for (i = 1; i < size; i++) { |
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n >>= NB; |
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buff[islittle ? i : size - 1 - i] = (char)(n & MC); |
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} |
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if (neg && size > SZINT) { /* negative number need sign extension? */ |
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for (i = SZINT; i < size; i++) /* correct extra bytes */ |
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buff[islittle ? i : size - 1 - i] = (char)MC; |
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} |
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luaL_addsize(b, size); /* add result to buffer */ |
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} |
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/* |
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** Copy 'size' bytes from 'src' to 'dest', correcting endianness if |
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** given 'islittle' is different from native endianness. |
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*/ |
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static void copywithendian (volatile char *dest, volatile const char *src, |
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int size, int islittle) { |
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if (islittle == nativeendian.little) { |
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while (size-- != 0) |
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*(dest++) = *(src++); |
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} |
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else { |
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dest += size - 1; |
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while (size-- != 0) |
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*(dest--) = *(src++); |
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} |
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} |
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static int str_pack (lua_State *L) { |
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luaL_Buffer b; |
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Header h; |
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const char *fmt = luaL_checkstring(L, 1); /* format string */ |
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int arg = 1; /* current argument to pack */ |
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size_t totalsize = 0; /* accumulate total size of result */ |
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initheader(L, &h); |
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lua_pushnil(L); /* mark to separate arguments from string buffer */ |
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luaL_buffinit(L, &b); |
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while (*fmt != '\0') { |
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int size, ntoalign; |
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KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign); |
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totalsize += ntoalign + size; |
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while (ntoalign-- > 0) |
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luaL_addchar(&b, LUAL_PACKPADBYTE); /* fill alignment */ |
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arg++; |
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switch (opt) { |
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case Kint: { /* signed integers */ |
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lua_Integer n = luaL_checkinteger(L, arg); |
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if (size < SZINT) { /* need overflow check? */ |
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lua_Integer lim = (lua_Integer)1 << ((size * NB) - 1); |
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luaL_argcheck(L, -lim <= n && n < lim, arg, "integer overflow"); |
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} |
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packint(&b, (lua_Unsigned)n, h.islittle, size, (n < 0)); |
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break; |
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} |
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case Kuint: { /* unsigned integers */ |
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lua_Integer n = luaL_checkinteger(L, arg); |
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if (size < SZINT) /* need overflow check? */ |
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luaL_argcheck(L, (lua_Unsigned)n < ((lua_Unsigned)1 << (size * NB)), |
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arg, "unsigned overflow"); |
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packint(&b, (lua_Unsigned)n, h.islittle, size, 0); |
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break; |
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} |
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case Kfloat: { /* floating-point options */ |
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volatile Ftypes u; |
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char *buff = luaL_prepbuffsize(&b, size); |
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lua_Number n = luaL_checknumber(L, arg); /* get argument */ |
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if (size == sizeof(u.f)) u.f = (float)n; /* copy it into 'u' */ |
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else if (size == sizeof(u.d)) u.d = (double)n; |
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else u.n = n; |
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/* move 'u' to final result, correcting endianness if needed */ |
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copywithendian(buff, u.buff, size, h.islittle); |
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luaL_addsize(&b, size); |
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break; |
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} |
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case Kchar: { /* fixed-size string */ |
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size_t len; |
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const char *s = luaL_checklstring(L, arg, &len); |
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luaL_argcheck(L, len <= (size_t)size, arg, |
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"string longer than given size"); |
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luaL_addlstring(&b, s, len); /* add string */ |
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while (len++ < (size_t)size) /* pad extra space */ |
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luaL_addchar(&b, LUAL_PACKPADBYTE); |
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break; |
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} |
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case Kstring: { /* strings with length count */ |
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size_t len; |
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const char *s = luaL_checklstring(L, arg, &len); |
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luaL_argcheck(L, size >= (int)sizeof(size_t) || |
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len < ((size_t)1 << (size * NB)), |
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arg, "string length does not fit in given size"); |
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packint(&b, (lua_Unsigned)len, h.islittle, size, 0); /* pack length */ |
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luaL_addlstring(&b, s, len); |
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totalsize += len; |
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break; |
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} |
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case Kzstr: { /* zero-terminated string */ |
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size_t len; |
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const char *s = luaL_checklstring(L, arg, &len); |
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luaL_argcheck(L, strlen(s) == len, arg, "string contains zeros"); |
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luaL_addlstring(&b, s, len); |
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luaL_addchar(&b, '\0'); /* add zero at the end */ |
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totalsize += len + 1; |
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break; |
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} |
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case Kpadding: luaL_addchar(&b, LUAL_PACKPADBYTE); /* FALLTHROUGH */ |
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case Kpaddalign: case Knop: |
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arg--; /* undo increment */ |
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break; |
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} |
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} |
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luaL_pushresult(&b); |
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return 1; |
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} |
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static int str_packsize (lua_State *L) { |
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Header h; |
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const char *fmt = luaL_checkstring(L, 1); /* format string */ |
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size_t totalsize = 0; /* accumulate total size of result */ |
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initheader(L, &h); |
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while (*fmt != '\0') { |
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int size, ntoalign; |
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KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign); |
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size += ntoalign; /* total space used by option */ |
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luaL_argcheck(L, totalsize <= MAXSIZE - size, 1, |
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"format result too large"); |
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totalsize += size; |
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switch (opt) { |
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case Kstring: /* strings with length count */ |
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case Kzstr: /* zero-terminated string */ |
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luaL_argerror(L, 1, "variable-length format"); |
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/* call never return, but to avoid warnings: *//* FALLTHROUGH */ |
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default: break; |
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} |
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} |
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lua_pushinteger(L, (lua_Integer)totalsize); |
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return 1; |
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} |
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/* |
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** Unpack an integer with 'size' bytes and 'islittle' endianness. |
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** If size is smaller than the size of a Lua integer and integer |
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** is signed, must do sign extension (propagating the sign to the |
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** higher bits); if size is larger than the size of a Lua integer, |
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** it must check the unread bytes to see whether they do not cause an |
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** overflow. |
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*/ |
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static lua_Integer unpackint (lua_State *L, const char *str, |
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int islittle, int size, int issigned) { |
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lua_Unsigned res = 0; |
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int i; |
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int limit = (size <= SZINT) ? size : SZINT; |
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for (i = limit - 1; i >= 0; i--) { |
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res <<= NB; |
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res |= (lua_Unsigned)(unsigned char)str[islittle ? i : size - 1 - i]; |
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} |
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if (size < SZINT) { /* real size smaller than lua_Integer? */ |
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if (issigned) { /* needs sign extension? */ |
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lua_Unsigned mask = (lua_Unsigned)1 << (size*NB - 1); |
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res = ((res ^ mask) - mask); /* do sign extension */ |
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} |
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} |
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else if (size > SZINT) { /* must check unread bytes */ |
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int mask = (!issigned || (lua_Integer)res >= 0) ? 0 : MC; |
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for (i = limit; i < size; i++) { |
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if ((unsigned char)str[islittle ? i : size - 1 - i] != mask) |
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luaL_error(L, "%d-byte integer does not fit into Lua Integer", size); |
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} |
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} |
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return (lua_Integer)res; |
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} |
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static int str_unpack (lua_State *L) { |
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Header h; |
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const char *fmt = luaL_checkstring(L, 1); |
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size_t ld; |
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const char *data = luaL_checklstring(L, 2, &ld); |
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size_t pos = (size_t)posrelat(luaL_optinteger(L, 3, 1), ld) - 1; |
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int n = 0; /* number of results */ |
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luaL_argcheck(L, pos <= ld, 3, "initial position out of string"); |
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initheader(L, &h); |
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while (*fmt != '\0') { |
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int size, ntoalign; |
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KOption opt = getdetails(&h, pos, &fmt, &size, &ntoalign); |
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if ((size_t)ntoalign + size > ~pos || pos + ntoalign + size > ld) |
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luaL_argerror(L, 2, "data string too short"); |
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pos += ntoalign; /* skip alignment */ |
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/* stack space for item + next position */ |
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luaL_checkstack(L, 2, "too many results"); |
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n++; |
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switch (opt) { |
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case Kint: |
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case Kuint: { |
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lua_Integer res = unpackint(L, data + pos, h.islittle, size, |
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(opt == Kint)); |
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lua_pushinteger(L, res); |
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break; |
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} |
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case Kfloat: { |
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volatile Ftypes u; |
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lua_Number num; |
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copywithendian(u.buff, data + pos, size, h.islittle); |
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if (size == sizeof(u.f)) num = (lua_Number)u.f; |
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else if (size == sizeof(u.d)) num = (lua_Number)u.d; |
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else num = u.n; |
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lua_pushnumber(L, num); |
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break; |
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} |
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case Kchar: { |
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lua_pushlstring(L, data + pos, size); |
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break; |
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} |
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case Kstring: { |
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size_t len = (size_t)unpackint(L, data + pos, h.islittle, size, 0); |
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luaL_argcheck(L, pos + len + size <= ld, 2, "data string too short"); |
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lua_pushlstring(L, data + pos + size, len); |
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pos += len; /* skip string */ |
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break; |
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} |
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case Kzstr: { |
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size_t len = (int)strlen(data + pos); |
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lua_pushlstring(L, data + pos, len); |
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pos += len + 1; /* skip string plus final '\0' */ |
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break; |
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} |
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case Kpaddalign: case Kpadding: case Knop: |
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n--; /* undo increment */ |
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break; |
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} |
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pos += size; |
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} |
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lua_pushinteger(L, pos + 1); /* next position */ |
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return n + 1; |
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} |
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/* }====================================================== */ |
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static const luaL_Reg strlib[] = { |
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{"byte", str_byte}, |
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{"char", str_char}, |
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{"dump", str_dump}, |
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{"find", str_find}, |
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{"format", str_format}, |
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{"gmatch", gmatch}, |
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{"gsub", str_gsub}, |
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{"len", str_len}, |
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{"lower", str_lower}, |
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{"match", str_match}, |
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{"rep", str_rep}, |
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{"reverse", str_reverse}, |
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{"sub", str_sub}, |
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{"upper", str_upper}, |
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{"pack", str_pack}, |
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{"packsize", str_packsize}, |
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{"unpack", str_unpack}, |
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{NULL, NULL} |
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}; |
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static void createmetatable (lua_State *L) { |
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lua_createtable(L, 0, 1); /* table to be metatable for strings */ |
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lua_pushliteral(L, ""); /* dummy string */ |
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lua_pushvalue(L, -2); /* copy table */ |
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lua_setmetatable(L, -2); /* set table as metatable for strings */ |
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lua_pop(L, 1); /* pop dummy string */ |
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lua_pushvalue(L, -2); /* get string library */ |
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lua_setfield(L, -2, "__index"); /* metatable.__index = string */ |
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lua_pop(L, 1); /* pop metatable */ |
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} |
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/* |
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** Open string library |
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*/ |
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LUAMOD_API int luaopen_string (lua_State *L) { |
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luaL_newlib(L, strlib); |
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createmetatable(L); |
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return 1; |
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} |
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