/src/middleware/lua/lobject.c
C | 214 lines | 175 code | 27 blank | 12 comment | 41 complexity | 7321da04b0f05c85dfe7d37f4cd4400f MD5 | raw file
1/* 2** $Id: lobject.c,v 2.22.1.1 2007/12/27 13:02:25 roberto Exp $ 3** Some generic functions over Lua objects 4** See Copyright Notice in lua.h 5*/ 6 7#include <ctype.h> 8#include <stdarg.h> 9#include <stdio.h> 10#include <stdlib.h> 11#include <string.h> 12 13#define lobject_c 14#define LUA_CORE 15 16#include "lua.h" 17 18#include "ldo.h" 19#include "lmem.h" 20#include "lobject.h" 21#include "lstate.h" 22#include "lstring.h" 23#include "lvm.h" 24 25 26 27const TValue luaO_nilobject_ = {{NULL}, LUA_TNIL}; 28 29 30/* 31** converts an integer to a "floating point byte", represented as 32** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if 33** eeeee != 0 and (xxx) otherwise. 34*/ 35int luaO_int2fb (unsigned int x) { 36 int e = 0; /* expoent */ 37 while (x >= 16) { 38 x = (x+1) >> 1; 39 e++; 40 } 41 if (x < 8) return x; 42 else return ((e+1) << 3) | (cast_int(x) - 8); 43} 44 45 46/* converts back */ 47int luaO_fb2int (int x) { 48 int e = (x >> 3) & 31; 49 if (e == 0) return x; 50 else return ((x & 7)+8) << (e - 1); 51} 52 53 54int luaO_log2 (unsigned int x) { 55 static const lu_byte log_2[256] = { 56 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, 57 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, 58 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 59 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 60 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 61 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 62 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 63 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8 64 }; 65 int l = -1; 66 while (x >= 256) { l += 8; x >>= 8; } 67 return l + log_2[x]; 68 69} 70 71 72int luaO_rawequalObj (const TValue *t1, const TValue *t2) { 73 if (ttype(t1) != ttype(t2)) return 0; 74 else switch (ttype(t1)) { 75 case LUA_TNIL: 76 return 1; 77 case LUA_TNUMBER: 78 return luai_numeq(nvalue(t1), nvalue(t2)); 79 case LUA_TBOOLEAN: 80 return bvalue(t1) == bvalue(t2); /* boolean true must be 1 !! */ 81 case LUA_TLIGHTUSERDATA: 82 return pvalue(t1) == pvalue(t2); 83 default: 84 lua_assert(iscollectable(t1)); 85 return gcvalue(t1) == gcvalue(t2); 86 } 87} 88 89 90int luaO_str2d (const char *s, lua_Number *result) { 91 char *endptr; 92 *result = lua_str2number(s, &endptr); 93 if (endptr == s) return 0; /* conversion failed */ 94 if (*endptr == 'x' || *endptr == 'X') /* maybe an hexadecimal constant? */ 95 *result = cast_num(strtoul(s, &endptr, 16)); 96 if (*endptr == '\0') return 1; /* most common case */ 97 while (isspace(cast(unsigned char, *endptr))) endptr++; 98 if (*endptr != '\0') return 0; /* invalid trailing characters? */ 99 return 1; 100} 101 102 103 104static void pushstr (lua_State *L, const char *str) { 105 setsvalue2s(L, L->top, luaS_new(L, str)); 106 incr_top(L); 107} 108 109 110/* this function handles only `%d', `%c', %f, %p, and `%s' formats */ 111const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) { 112 int n = 1; 113 pushstr(L, ""); 114 for (;;) { 115 const char *e = strchr(fmt, '%'); 116 if (e == NULL) break; 117 setsvalue2s(L, L->top, luaS_newlstr(L, fmt, e-fmt)); 118 incr_top(L); 119 switch (*(e+1)) { 120 case 's': { 121 const char *s = va_arg(argp, char *); 122 if (s == NULL) s = "(null)"; 123 pushstr(L, s); 124 break; 125 } 126 case 'c': { 127 char buff[2]; 128 buff[0] = cast(char, va_arg(argp, int)); 129 buff[1] = '\0'; 130 pushstr(L, buff); 131 break; 132 } 133 case 'd': { 134 setnvalue(L->top, cast_num(va_arg(argp, int))); 135 incr_top(L); 136 break; 137 } 138 case 'f': { 139 setnvalue(L->top, cast_num(va_arg(argp, l_uacNumber))); 140 incr_top(L); 141 break; 142 } 143 case 'p': { 144 char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */ 145 sprintf(buff, "%p", va_arg(argp, void *)); 146 pushstr(L, buff); 147 break; 148 } 149 case '%': { 150 pushstr(L, "%"); 151 break; 152 } 153 default: { 154 char buff[3]; 155 buff[0] = '%'; 156 buff[1] = *(e+1); 157 buff[2] = '\0'; 158 pushstr(L, buff); 159 break; 160 } 161 } 162 n += 2; 163 fmt = e+2; 164 } 165 pushstr(L, fmt); 166 luaV_concat(L, n+1, cast_int(L->top - L->base) - 1); 167 L->top -= n; 168 return svalue(L->top - 1); 169} 170 171 172const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) { 173 const char *msg; 174 va_list argp; 175 va_start(argp, fmt); 176 msg = luaO_pushvfstring(L, fmt, argp); 177 va_end(argp); 178 return msg; 179} 180 181 182void luaO_chunkid (char *out, const char *source, size_t bufflen) { 183 if (*source == '=') { 184 strncpy(out, source+1, bufflen); /* remove first char */ 185 out[bufflen-1] = '\0'; /* ensures null termination */ 186 } 187 else { /* out = "source", or "...source" */ 188 if (*source == '@') { 189 size_t l; 190 source++; /* skip the `@' */ 191 bufflen -= sizeof(" '...' "); 192 l = strlen(source); 193 strcpy(out, ""); 194 if (l > bufflen) { 195 source += (l-bufflen); /* get last part of file name */ 196 strcat(out, "..."); 197 } 198 strcat(out, source); 199 } 200 else { /* out = [string "string"] */ 201 size_t len = strcspn(source, "\n\r"); /* stop at first newline */ 202 bufflen -= sizeof(" [string \"...\"] "); 203 if (len > bufflen) len = bufflen; 204 strcpy(out, "[string \""); 205 if (source[len] != '\0') { /* must truncate? */ 206 strncat(out, source, len); 207 strcat(out, "..."); 208 } 209 else 210 strcat(out, source); 211 strcat(out, "\"]"); 212 } 213 } 214}