1/*
2** $Id: lobject.c,v 2.58.1.1 2013/04/12 18:48:47 roberto Exp $
3** Some generic functions over Lua objects
4** See Copyright Notice in lua.h
5*/
6
7#include <sys/zfs_context.h>
8
9#define lobject_c
10#define LUA_CORE
11
12#include "lua.h"
13
14#include "lctype.h"
15#include "ldebug.h"
16#include "ldo.h"
17#include "lmem.h"
18#include "lobject.h"
19#include "lstate.h"
20#include "lstring.h"
21#include "lvm.h"
22
23
24
25LUAI_DDEF const TValue luaO_nilobject_ = {NILCONSTANT};
26
27
28/*
29** converts an integer to a "floating point byte", represented as
30** (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if
31** eeeee != 0 and (xxx) otherwise.
32*/
33int luaO_int2fb (unsigned int x) {
34  int e = 0;  /* exponent */
35  if (x < 8) return x;
36  while (x >= 0x10) {
37    x = (x+1) >> 1;
38    e++;
39  }
40  return ((e+1) << 3) | (cast_int(x) - 8);
41}
42
43
44/* converts back */
45int luaO_fb2int (int x) {
46  int e = (x >> 3) & 0x1f;
47  if (e == 0) return x;
48  else return ((x & 7) + 8) << (e - 1);
49}
50
51
52int luaO_ceillog2 (unsigned int x) {
53  static const lu_byte log_2[256] = {
54    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,
55    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,
56    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,
57    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,
58    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,
59    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,
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  };
63  int l = 0;
64  x--;
65  while (x >= 256) { l += 8; x >>= 8; }
66  return l + log_2[x];
67}
68
69
70lua_Number luaO_arith (int op, lua_Number v1, lua_Number v2) {
71  switch (op) {
72    case LUA_OPADD: return luai_numadd(NULL, v1, v2);
73    case LUA_OPSUB: return luai_numsub(NULL, v1, v2);
74    case LUA_OPMUL: return luai_nummul(NULL, v1, v2);
75    case LUA_OPDIV: return luai_numdiv(NULL, v1, v2);
76    case LUA_OPMOD: return luai_nummod(NULL, v1, v2);
77    case LUA_OPPOW: return luai_numpow(NULL, v1, v2);
78    case LUA_OPUNM: return luai_numunm(NULL, v1);
79    default: lua_assert(0); return 0;
80  }
81}
82
83
84int luaO_hexavalue (int c) {
85  if (lisdigit(c)) return c - '0';
86  else return ltolower(c) - 'a' + 10;
87}
88
89
90#if !defined(lua_strx2number)
91
92
93
94static int isneg (const char **s) {
95  if (**s == '-') { (*s)++; return 1; }
96  else if (**s == '+') (*s)++;
97  return 0;
98}
99
100
101static lua_Number readhexa (const char **s, lua_Number r, int *count) {
102  for (; lisxdigit(cast_uchar(**s)); (*s)++) {  /* read integer part */
103    r = (r * cast_num(16.0)) + cast_num(luaO_hexavalue(cast_uchar(**s)));
104    (*count)++;
105  }
106  return r;
107}
108
109
110/*
111** convert an hexadecimal numeric string to a number, following
112** C99 specification for 'strtod'
113*/
114static lua_Number lua_strx2number (const char *s, char **endptr) {
115  lua_Number r = 0.0;
116  int e = 0, i = 0;
117  int neg = 0;  /* 1 if number is negative */
118  *endptr = cast(char *, s);  /* nothing is valid yet */
119  while (lisspace(cast_uchar(*s))) s++;  /* skip initial spaces */
120  neg = isneg(&s);  /* check signal */
121  if (!(*s == '0' && (*(s + 1) == 'x' || *(s + 1) == 'X')))  /* check '0x' */
122    return 0.0;  /* invalid format (no '0x') */
123  s += 2;  /* skip '0x' */
124  r = readhexa(&s, r, &i);  /* read integer part */
125  if (*s == '.') {
126    s++;  /* skip dot */
127    r = readhexa(&s, r, &e);  /* read fractional part */
128  }
129  if (i == 0 && e == 0)
130    return 0.0;  /* invalid format (no digit) */
131  e *= -4;  /* each fractional digit divides value by 2^-4 */
132  *endptr = cast(char *, s);  /* valid up to here */
133  if (*s == 'p' || *s == 'P') {  /* exponent part? */
134    int exp1 = 0;
135    int neg1;
136    s++;  /* skip 'p' */
137    neg1 = isneg(&s);  /* signal */
138    if (!lisdigit(cast_uchar(*s)))
139      goto ret;  /* must have at least one digit */
140    while (lisdigit(cast_uchar(*s)))  /* read exponent */
141      exp1 = exp1 * 10 + *(s++) - '0';
142    if (neg1) exp1 = -exp1;
143    e += exp1;
144  }
145  *endptr = cast(char *, s);  /* valid up to here */
146 ret:
147  if (neg) r = -r;
148  return (r * (1 << e));
149}
150
151#endif
152
153
154int luaO_str2d (const char *s, size_t len, lua_Number *result) {
155  char *endptr;
156  if (strpbrk(s, "nN"))  /* reject 'inf' and 'nan' */
157    return 0;
158  else if (strpbrk(s, "xX"))  /* hexa? */
159    *result = lua_strx2number(s, &endptr);
160  else
161    *result = lua_str2number(s, &endptr);
162  if (endptr == s) return 0;  /* nothing recognized */
163  while (lisspace(cast_uchar(*endptr))) endptr++;
164  return (endptr == s + len);  /* OK if no trailing characters */
165}
166
167
168
169static void pushstr (lua_State *L, const char *str, size_t l) {
170  setsvalue2s(L, L->top++, luaS_newlstr(L, str, l));
171}
172
173
174/* this function handles only `%d', `%c', %f, %p, and `%s' formats */
175const char *luaO_pushvfstring (lua_State *L, const char *fmt, va_list argp) {
176  int n = 0;
177  for (;;) {
178    const char *e = strchr(fmt, '%');
179    if (e == NULL) break;
180    luaD_checkstack(L, 2);  /* fmt + item */
181    pushstr(L, fmt, e - fmt);
182    switch (*(e+1)) {
183      case 's': {
184        const char *s = va_arg(argp, char *);
185        if (s == NULL) s = "(null)";
186        pushstr(L, s, strlen(s));
187        break;
188      }
189      case 'c': {
190        char buff;
191        buff = cast(char, va_arg(argp, int));
192        pushstr(L, &buff, 1);
193        break;
194      }
195      case 'd': {
196        setnvalue(L->top++, cast_num(va_arg(argp, int)));
197        break;
198      }
199      case 'f': {
200        setnvalue(L->top++, cast_num(va_arg(argp, l_uacNumber)));
201        break;
202      }
203      case 'p': {
204        char buff[4*sizeof(void *) + 8]; /* should be enough space for a `%p' */
205        int l = lcompat_sprintf(buff, "%p", va_arg(argp, void *));
206        pushstr(L, buff, l);
207        break;
208      }
209      case '%': {
210        pushstr(L, "%", 1);
211        break;
212      }
213      default: {
214        luaG_runerror(L,
215            "invalid option " LUA_QL("%%%c") " to " LUA_QL("lua_pushfstring"),
216            *(e + 1));
217      }
218    }
219    n += 2;
220    fmt = e+2;
221  }
222  luaD_checkstack(L, 1);
223  pushstr(L, fmt, strlen(fmt));
224  if (n > 0) luaV_concat(L, n + 1);
225  return svalue(L->top - 1);
226}
227
228
229const char *luaO_pushfstring (lua_State *L, const char *fmt, ...) {
230  const char *msg;
231  va_list argp;
232  va_start(argp, fmt);
233  msg = luaO_pushvfstring(L, fmt, argp);
234  va_end(argp);
235  return msg;
236}
237
238
239/* number of chars of a literal string without the ending \0 */
240#define LL(x)	(sizeof(x)/sizeof(char) - 1)
241
242#define RETS	"..."
243#define PRE	"[string \""
244#define POS	"\"]"
245
246#define addstr(a,b,l)	( memcpy(a,b,(l) * sizeof(char)), a += (l) )
247
248void luaO_chunkid (char *out, const char *source, size_t bufflen) {
249  size_t l = strlen(source);
250  if (*source == '=') {  /* 'literal' source */
251    if (l <= bufflen)  /* small enough? */
252      memcpy(out, source + 1, l * sizeof(char));
253    else {  /* truncate it */
254      addstr(out, source + 1, bufflen - 1);
255      *out = '\0';
256    }
257  }
258  else if (*source == '@') {  /* file name */
259    if (l <= bufflen)  /* small enough? */
260      memcpy(out, source + 1, l * sizeof(char));
261    else {  /* add '...' before rest of name */
262      addstr(out, RETS, LL(RETS));
263      bufflen -= LL(RETS);
264      memcpy(out, source + 1 + l - bufflen, bufflen * sizeof(char));
265    }
266  }
267  else {  /* string; format as [string "source"] */
268    const char *nl = strchr(source, '\n');  /* find first new line (if any) */
269    addstr(out, PRE, LL(PRE));  /* add prefix */
270    bufflen -= LL(PRE RETS POS) + 1;  /* save space for prefix+suffix+'\0' */
271    if (l < bufflen && nl == NULL) {  /* small one-line source? */
272      addstr(out, source, l);  /* keep it */
273    }
274    else {
275      if (nl != NULL) l = nl - source;  /* stop at first newline */
276      if (l > bufflen) l = bufflen;
277      addstr(out, source, l);
278      addstr(out, RETS, LL(RETS));
279    }
280    memcpy(out, POS, (LL(POS) + 1) * sizeof(char));
281  }
282}
283
284