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author | Li Jin <dragon-fly@qq.com> | 2020-06-22 16:50:40 +0800 |
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committer | Li Jin <dragon-fly@qq.com> | 2020-06-22 16:50:40 +0800 |
commit | cd2b60b101a398cb9356d746364e70eaed1860f1 (patch) | |
tree | a1fe71b76faabc4883f16905a94164ce5c23e692 /src/lua/lutf8lib.c | |
parent | 88c1052e700f38cf3d8ad82d469da4c487760b7e (diff) | |
download | yuescript-cd2b60b101a398cb9356d746364e70eaed1860f1.tar.gz yuescript-cd2b60b101a398cb9356d746364e70eaed1860f1.tar.bz2 yuescript-cd2b60b101a398cb9356d746364e70eaed1860f1.zip |
add support for local variable declared with attribute 'close' and 'const' for Lua 5.4.
Diffstat (limited to 'src/lua/lutf8lib.c')
-rw-r--r-- | src/lua/lutf8lib.c | 289 |
1 files changed, 289 insertions, 0 deletions
diff --git a/src/lua/lutf8lib.c b/src/lua/lutf8lib.c new file mode 100644 index 0000000..901d985 --- /dev/null +++ b/src/lua/lutf8lib.c | |||
@@ -0,0 +1,289 @@ | |||
1 | /* | ||
2 | ** $Id: lutf8lib.c $ | ||
3 | ** Standard library for UTF-8 manipulation | ||
4 | ** See Copyright Notice in lua.h | ||
5 | */ | ||
6 | |||
7 | #define lutf8lib_c | ||
8 | #define LUA_LIB | ||
9 | |||
10 | #include "lprefix.h" | ||
11 | |||
12 | |||
13 | #include <assert.h> | ||
14 | #include <limits.h> | ||
15 | #include <stdlib.h> | ||
16 | #include <string.h> | ||
17 | |||
18 | #include "lua.h" | ||
19 | |||
20 | #include "lauxlib.h" | ||
21 | #include "lualib.h" | ||
22 | |||
23 | |||
24 | #define MAXUNICODE 0x10FFFFu | ||
25 | |||
26 | #define MAXUTF 0x7FFFFFFFu | ||
27 | |||
28 | /* | ||
29 | ** Integer type for decoded UTF-8 values; MAXUTF needs 31 bits. | ||
30 | */ | ||
31 | #if (UINT_MAX >> 30) >= 1 | ||
32 | typedef unsigned int utfint; | ||
33 | #else | ||
34 | typedef unsigned long utfint; | ||
35 | #endif | ||
36 | |||
37 | |||
38 | #define iscont(p) ((*(p) & 0xC0) == 0x80) | ||
39 | |||
40 | |||
41 | /* from strlib */ | ||
42 | /* translate a relative string position: negative means back from end */ | ||
43 | static lua_Integer u_posrelat (lua_Integer pos, size_t len) { | ||
44 | if (pos >= 0) return pos; | ||
45 | else if (0u - (size_t)pos > len) return 0; | ||
46 | else return (lua_Integer)len + pos + 1; | ||
47 | } | ||
48 | |||
49 | |||
50 | /* | ||
51 | ** Decode one UTF-8 sequence, returning NULL if byte sequence is | ||
52 | ** invalid. The array 'limits' stores the minimum value for each | ||
53 | ** sequence length, to check for overlong representations. Its first | ||
54 | ** entry forces an error for non-ascii bytes with no continuation | ||
55 | ** bytes (count == 0). | ||
56 | */ | ||
57 | static const char *utf8_decode (const char *s, utfint *val, int strict) { | ||
58 | static const utfint limits[] = | ||
59 | {~(utfint)0, 0x80, 0x800, 0x10000u, 0x200000u, 0x4000000u}; | ||
60 | unsigned int c = (unsigned char)s[0]; | ||
61 | utfint res = 0; /* final result */ | ||
62 | if (c < 0x80) /* ascii? */ | ||
63 | res = c; | ||
64 | else { | ||
65 | int count = 0; /* to count number of continuation bytes */ | ||
66 | for (; c & 0x40; c <<= 1) { /* while it needs continuation bytes... */ | ||
67 | unsigned int cc = (unsigned char)s[++count]; /* read next byte */ | ||
68 | if ((cc & 0xC0) != 0x80) /* not a continuation byte? */ | ||
69 | return NULL; /* invalid byte sequence */ | ||
70 | res = (res << 6) | (cc & 0x3F); /* add lower 6 bits from cont. byte */ | ||
71 | } | ||
72 | res |= ((utfint)(c & 0x7F) << (count * 5)); /* add first byte */ | ||
73 | if (count > 5 || res > MAXUTF || res < limits[count]) | ||
74 | return NULL; /* invalid byte sequence */ | ||
75 | s += count; /* skip continuation bytes read */ | ||
76 | } | ||
77 | if (strict) { | ||
78 | /* check for invalid code points; too large or surrogates */ | ||
79 | if (res > MAXUNICODE || (0xD800u <= res && res <= 0xDFFFu)) | ||
80 | return NULL; | ||
81 | } | ||
82 | if (val) *val = res; | ||
83 | return s + 1; /* +1 to include first byte */ | ||
84 | } | ||
85 | |||
86 | |||
87 | /* | ||
88 | ** utf8len(s [, i [, j [, lax]]]) --> number of characters that | ||
89 | ** start in the range [i,j], or nil + current position if 's' is not | ||
90 | ** well formed in that interval | ||
91 | */ | ||
92 | static int utflen (lua_State *L) { | ||
93 | lua_Integer n = 0; /* counter for the number of characters */ | ||
94 | size_t len; /* string length in bytes */ | ||
95 | const char *s = luaL_checklstring(L, 1, &len); | ||
96 | lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len); | ||
97 | lua_Integer posj = u_posrelat(luaL_optinteger(L, 3, -1), len); | ||
98 | int lax = lua_toboolean(L, 4); | ||
99 | luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 2, | ||
100 | "initial position out of bounds"); | ||
101 | luaL_argcheck(L, --posj < (lua_Integer)len, 3, | ||
102 | "final position out of bounds"); | ||
103 | while (posi <= posj) { | ||
104 | const char *s1 = utf8_decode(s + posi, NULL, !lax); | ||
105 | if (s1 == NULL) { /* conversion error? */ | ||
106 | luaL_pushfail(L); /* return fail ... */ | ||
107 | lua_pushinteger(L, posi + 1); /* ... and current position */ | ||
108 | return 2; | ||
109 | } | ||
110 | posi = s1 - s; | ||
111 | n++; | ||
112 | } | ||
113 | lua_pushinteger(L, n); | ||
114 | return 1; | ||
115 | } | ||
116 | |||
117 | |||
118 | /* | ||
119 | ** codepoint(s, [i, [j [, lax]]]) -> returns codepoints for all | ||
120 | ** characters that start in the range [i,j] | ||
121 | */ | ||
122 | static int codepoint (lua_State *L) { | ||
123 | size_t len; | ||
124 | const char *s = luaL_checklstring(L, 1, &len); | ||
125 | lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len); | ||
126 | lua_Integer pose = u_posrelat(luaL_optinteger(L, 3, posi), len); | ||
127 | int lax = lua_toboolean(L, 4); | ||
128 | int n; | ||
129 | const char *se; | ||
130 | luaL_argcheck(L, posi >= 1, 2, "out of bounds"); | ||
131 | luaL_argcheck(L, pose <= (lua_Integer)len, 3, "out of bounds"); | ||
132 | if (posi > pose) return 0; /* empty interval; return no values */ | ||
133 | if (pose - posi >= INT_MAX) /* (lua_Integer -> int) overflow? */ | ||
134 | return luaL_error(L, "string slice too long"); | ||
135 | n = (int)(pose - posi) + 1; /* upper bound for number of returns */ | ||
136 | luaL_checkstack(L, n, "string slice too long"); | ||
137 | n = 0; /* count the number of returns */ | ||
138 | se = s + pose; /* string end */ | ||
139 | for (s += posi - 1; s < se;) { | ||
140 | utfint code; | ||
141 | s = utf8_decode(s, &code, !lax); | ||
142 | if (s == NULL) | ||
143 | return luaL_error(L, "invalid UTF-8 code"); | ||
144 | lua_pushinteger(L, code); | ||
145 | n++; | ||
146 | } | ||
147 | return n; | ||
148 | } | ||
149 | |||
150 | |||
151 | static void pushutfchar (lua_State *L, int arg) { | ||
152 | lua_Unsigned code = (lua_Unsigned)luaL_checkinteger(L, arg); | ||
153 | luaL_argcheck(L, code <= MAXUTF, arg, "value out of range"); | ||
154 | lua_pushfstring(L, "%U", (long)code); | ||
155 | } | ||
156 | |||
157 | |||
158 | /* | ||
159 | ** utfchar(n1, n2, ...) -> char(n1)..char(n2)... | ||
160 | */ | ||
161 | static int utfchar (lua_State *L) { | ||
162 | int n = lua_gettop(L); /* number of arguments */ | ||
163 | if (n == 1) /* optimize common case of single char */ | ||
164 | pushutfchar(L, 1); | ||
165 | else { | ||
166 | int i; | ||
167 | luaL_Buffer b; | ||
168 | luaL_buffinit(L, &b); | ||
169 | for (i = 1; i <= n; i++) { | ||
170 | pushutfchar(L, i); | ||
171 | luaL_addvalue(&b); | ||
172 | } | ||
173 | luaL_pushresult(&b); | ||
174 | } | ||
175 | return 1; | ||
176 | } | ||
177 | |||
178 | |||
179 | /* | ||
180 | ** offset(s, n, [i]) -> index where n-th character counting from | ||
181 | ** position 'i' starts; 0 means character at 'i'. | ||
182 | */ | ||
183 | static int byteoffset (lua_State *L) { | ||
184 | size_t len; | ||
185 | const char *s = luaL_checklstring(L, 1, &len); | ||
186 | lua_Integer n = luaL_checkinteger(L, 2); | ||
187 | lua_Integer posi = (n >= 0) ? 1 : len + 1; | ||
188 | posi = u_posrelat(luaL_optinteger(L, 3, posi), len); | ||
189 | luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 3, | ||
190 | "position out of bounds"); | ||
191 | if (n == 0) { | ||
192 | /* find beginning of current byte sequence */ | ||
193 | while (posi > 0 && iscont(s + posi)) posi--; | ||
194 | } | ||
195 | else { | ||
196 | if (iscont(s + posi)) | ||
197 | return luaL_error(L, "initial position is a continuation byte"); | ||
198 | if (n < 0) { | ||
199 | while (n < 0 && posi > 0) { /* move back */ | ||
200 | do { /* find beginning of previous character */ | ||
201 | posi--; | ||
202 | } while (posi > 0 && iscont(s + posi)); | ||
203 | n++; | ||
204 | } | ||
205 | } | ||
206 | else { | ||
207 | n--; /* do not move for 1st character */ | ||
208 | while (n > 0 && posi < (lua_Integer)len) { | ||
209 | do { /* find beginning of next character */ | ||
210 | posi++; | ||
211 | } while (iscont(s + posi)); /* (cannot pass final '\0') */ | ||
212 | n--; | ||
213 | } | ||
214 | } | ||
215 | } | ||
216 | if (n == 0) /* did it find given character? */ | ||
217 | lua_pushinteger(L, posi + 1); | ||
218 | else /* no such character */ | ||
219 | luaL_pushfail(L); | ||
220 | return 1; | ||
221 | } | ||
222 | |||
223 | |||
224 | static int iter_aux (lua_State *L, int strict) { | ||
225 | size_t len; | ||
226 | const char *s = luaL_checklstring(L, 1, &len); | ||
227 | lua_Integer n = lua_tointeger(L, 2) - 1; | ||
228 | if (n < 0) /* first iteration? */ | ||
229 | n = 0; /* start from here */ | ||
230 | else if (n < (lua_Integer)len) { | ||
231 | n++; /* skip current byte */ | ||
232 | while (iscont(s + n)) n++; /* and its continuations */ | ||
233 | } | ||
234 | if (n >= (lua_Integer)len) | ||
235 | return 0; /* no more codepoints */ | ||
236 | else { | ||
237 | utfint code; | ||
238 | const char *next = utf8_decode(s + n, &code, strict); | ||
239 | if (next == NULL) | ||
240 | return luaL_error(L, "invalid UTF-8 code"); | ||
241 | lua_pushinteger(L, n + 1); | ||
242 | lua_pushinteger(L, code); | ||
243 | return 2; | ||
244 | } | ||
245 | } | ||
246 | |||
247 | |||
248 | static int iter_auxstrict (lua_State *L) { | ||
249 | return iter_aux(L, 1); | ||
250 | } | ||
251 | |||
252 | static int iter_auxlax (lua_State *L) { | ||
253 | return iter_aux(L, 0); | ||
254 | } | ||
255 | |||
256 | |||
257 | static int iter_codes (lua_State *L) { | ||
258 | int lax = lua_toboolean(L, 2); | ||
259 | luaL_checkstring(L, 1); | ||
260 | lua_pushcfunction(L, lax ? iter_auxlax : iter_auxstrict); | ||
261 | lua_pushvalue(L, 1); | ||
262 | lua_pushinteger(L, 0); | ||
263 | return 3; | ||
264 | } | ||
265 | |||
266 | |||
267 | /* pattern to match a single UTF-8 character */ | ||
268 | #define UTF8PATT "[\0-\x7F\xC2-\xFD][\x80-\xBF]*" | ||
269 | |||
270 | |||
271 | static const luaL_Reg funcs[] = { | ||
272 | {"offset", byteoffset}, | ||
273 | {"codepoint", codepoint}, | ||
274 | {"char", utfchar}, | ||
275 | {"len", utflen}, | ||
276 | {"codes", iter_codes}, | ||
277 | /* placeholders */ | ||
278 | {"charpattern", NULL}, | ||
279 | {NULL, NULL} | ||
280 | }; | ||
281 | |||
282 | |||
283 | LUAMOD_API int luaopen_utf8 (lua_State *L) { | ||
284 | luaL_newlib(L, funcs); | ||
285 | lua_pushlstring(L, UTF8PATT, sizeof(UTF8PATT)/sizeof(char) - 1); | ||
286 | lua_setfield(L, -2, "charpattern"); | ||
287 | return 1; | ||
288 | } | ||
289 | |||