/*** $Id: lutf8lib.c,v 1.13 2014/11/02 19:19:04 roberto Exp $** Standard library for UTF-8 manipulation** See Copyright Notice in lua.h*/ #define lutf8lib_c#define LUA_LIB #include "lprefix.h" #include <assert.h>#include <stdlib.h>#include <string.h> #include "lua.h" #include "lauxlib.h"#include "lualib.h" #define MAXUNICODE 0x10FFFF #define iscont(p) ((*(p) & 0xC0) == 0x80) /* from strlib *//* translate a relative string position: negative means back from end */static lua_Integer u_posrelat (lua_Integer pos, size_t len) { if (pos >= 0) return pos; else if (0u - (size_t)pos > len) return 0; else return (lua_Integer)len + pos + 1;} /*** Decode one UTF-8 sequence, returning NULL if byte sequence is invalid.*/static const char *utf8_decode (const char *o, int *val) { static unsigned int limits[] = {0xFF, 0x7F, 0x7FF, 0xFFFF}; const unsigned char *s = (const unsigned char *)o; unsigned int c = s[0]; unsigned int res = 0; /* final result */ if (c < 0x80) /* ascii? */ res = c; else { int count = 0; /* to count number of continuation bytes */ while (c & 0x40) { /* still have continuation bytes? */ int cc = s[++count]; /* read next byte */ if ((cc & 0xC0) != 0x80) /* not a continuation byte? */ return NULL; /* invalid byte sequence */ res = (res << 6) | (cc & 0x3F); /* add lower 6 bits from cont. byte */ c <<= 1; /* to test next bit */ } res |= ((c & 0x7F) << (count * 5)); /* add first byte */ if (count > 3 || res > MAXUNICODE || res <= limits[count]) return NULL; /* invalid byte sequence */ s += count; /* skip continuation bytes read */ } if (val) *val = res; return (const char *)s + 1; /* +1 to include first byte */} /*** utf8len(s [, i [, j]]) --> number of characters that start in the** range [i,j], or nil + current position if 's' is not well formed in** that interval*/static int utflen (lua_State *L) { int n = 0; size_t len; const char *s = luaL_checklstring(L, 1, &len); lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len); lua_Integer posj = u_posrelat(luaL_optinteger(L, 3, -1), len); luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 2, "initial position out of string"); luaL_argcheck(L, --posj < (lua_Integer)len, 3, "final position out of string"); while (posi <= posj) { const char *s1 = utf8_decode(s + posi, NULL); if (s1 == NULL) { /* conversion error? */ lua_pushnil(L); /* return nil ... */ lua_pushinteger(L, posi + 1); /* ... and current position */ return 2; } posi = s1 - s; n++; } lua_pushinteger(L, n); return 1;} /*** codepoint(s, [i, [j]]) -> returns codepoints for all characters** that start in the range [i,j]*/static int codepoint (lua_State *L) { size_t len; const char *s = luaL_checklstring(L, 1, &len); lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len); lua_Integer pose = u_posrelat(luaL_optinteger(L, 3, posi), len); int n; const char *se; luaL_argcheck(L, posi >= 1, 2, "out of range"); luaL_argcheck(L, pose <= (lua_Integer)len, 3, "out of range"); if (posi > pose) return 0; /* empty interval; return no values */ n = (int)(pose - posi + 1); if (posi + n <= pose) /* (lua_Integer -> int) overflow? */ return luaL_error(L, "string slice too long"); luaL_checkstack(L, n, "string slice too long"); n = 0; se = s + pose; for (s += posi - 1; s < se;) { int code; s = utf8_decode(s, &code); if (s == NULL) return luaL_error(L, "invalid UTF-8 code"); lua_pushinteger(L, code); n++; } return n;} static void pushutfchar (lua_State *L, int arg) { lua_Integer code = luaL_checkinteger(L, arg); luaL_argcheck(L, 0 <= code && code <= MAXUNICODE, arg, "value out of range"); lua_pushfstring(L, "%U", (long)code);} /*** utfchar(n1, n2, ...) -> char(n1)..char(n2)...*/static int utfchar (lua_State *L) { int n = lua_gettop(L); /* number of arguments */ if (n == 1) /* optimize common case of single char */ pushutfchar(L, 1); else { int i; luaL_Buffer b; luaL_buffinit(L, &b); for (i = 1; i <= n; i++) { pushutfchar(L, i); luaL_addvalue(&b); } luaL_pushresult(&b); } return 1;} /*** offset(s, n, [i]) -> index where n-th character counting from** position 'i' starts; 0 means character at 'i'.*/static int byteoffset (lua_State *L) { size_t len; const char *s = luaL_checklstring(L, 1, &len); lua_Integer n = luaL_checkinteger(L, 2); lua_Integer posi = (n >= 0) ? 1 : len + 1; posi = u_posrelat(luaL_optinteger(L, 3, posi), len); luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 3, "position out of range"); if (n == 0) { /* find beginning of current byte sequence */ while (posi > 0 && iscont(s + posi)) posi--; } else { if (iscont(s + posi)) luaL_error(L, "initial position is a continuation byte"); if (n < 0) { while (n < 0 && posi > 0) { /* move back */ do { /* find beginning of previous character */ posi--; } while (posi > 0 && iscont(s + posi)); n++; } } else { n--; /* do not move for 1st character */ while (n > 0 && posi < (lua_Integer)len) { do { /* find beginning of next character */ posi++; } while (iscont(s + posi)); /* (cannot pass final '\0') */ n--; } } } if (n == 0) /* did it find given character? */ lua_pushinteger(L, posi + 1); else /* no such character */ lua_pushnil(L); return 1; } static int iter_aux (lua_State *L) { size_t len; const char *s = luaL_checklstring(L, 1, &len); lua_Integer n = lua_tointeger(L, 2) - 1; if (n < 0) /* first iteration? */ n = 0; /* start from here */ else if (n < (lua_Integer)len) { n++; /* skip current byte */ while (iscont(s + n)) n++; /* and its continuations */ } if (n >= (lua_Integer)len) return 0; /* no more codepoints */ else { int code; const char *next = utf8_decode(s + n, &code); if (next == NULL || iscont(next)) return luaL_error(L, "invalid UTF-8 code"); lua_pushinteger(L, n + 1); lua_pushinteger(L, code); return 2; }} static int iter_codes (lua_State *L) { luaL_checkstring(L, 1); lua_pushcfunction(L, iter_aux); lua_pushvalue(L, 1); lua_pushinteger(L, 0); return 3;} /* pattern to match a single UTF-8 character */#define UTF8PATT "[\0-\x7F\xC2-\xF4][\x80-\xBF]*" static struct luaL_Reg funcs[] = { {"offset", byteoffset}, {"codepoint", codepoint}, {"char", utfchar}, {"len", utflen}, {"codes", iter_codes}, /* placeholders */ {"charpattern", NULL}, {NULL, NULL}}; LUAMOD_API int luaopen_utf8 (lua_State *L) { luaL_newlib(L, funcs); lua_pushliteral(L, UTF8PATT); lua_setfield(L, -2, "charpattern"); return 1;}
/*
** $Id: lutf8lib.c,v 1.13 2014/11/02 19:19:04 roberto Exp $
** Standard library for UTF-8 manipulation
** See Copyright Notice in lua.h
*/
#define lutf8lib_c
#define LUA_LIB
#include "lprefix.h"
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
#define MAXUNICODE 0x10FFFF
#define iscont(p) ((*(p) & 0xC0) == 0x80)
/* from strlib */
/* translate a relative string position: negative means back from end */
static lua_Integer u_posrelat (lua_Integer pos, size_t len) {
if (pos >= 0) return pos;
else if (0u - (size_t)pos > len) return 0;
else return (lua_Integer)len + pos + 1;
}
/*
** Decode one UTF-8 sequence, returning NULL if byte sequence is invalid.
*/
static const char *utf8_decode (const char *o, int *val) {
static unsigned int limits[] = {0xFF, 0x7F, 0x7FF, 0xFFFF};
const unsigned char *s = (const unsigned char *)o;
unsigned int c = s[0];
unsigned int res = 0; /* final result */
if (c < 0x80) /* ascii? */
res = c;
else {
int count = 0; /* to count number of continuation bytes */
while (c & 0x40) { /* still have continuation bytes? */
int cc = s[++count]; /* read next byte */
if ((cc & 0xC0) != 0x80) /* not a continuation byte? */
return NULL; /* invalid byte sequence */
res = (res << 6) | (cc & 0x3F); /* add lower 6 bits from cont. byte */
c <<= 1; /* to test next bit */
}
res |= ((c & 0x7F) << (count * 5)); /* add first byte */
if (count > 3 || res > MAXUNICODE || res <= limits[count])
return NULL; /* invalid byte sequence */
s += count; /* skip continuation bytes read */
}
if (val) *val = res;
return (const char *)s + 1; /* +1 to include first byte */
}
/*
** utf8len(s [, i [, j]]) --> number of characters that start in the
** range [i,j], or nil + current position if 's' is not well formed in
** that interval
*/
static int utflen (lua_State *L) {
int n = 0;
size_t len;
const char *s = luaL_checklstring(L, 1, &len);
lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len);
lua_Integer posj = u_posrelat(luaL_optinteger(L, 3, -1), len);
luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 2,
"initial position out of string");
luaL_argcheck(L, --posj < (lua_Integer)len, 3,
"final position out of string");
while (posi <= posj) {
const char *s1 = utf8_decode(s + posi, NULL);
if (s1 == NULL) { /* conversion error? */
lua_pushnil(L); /* return nil ... */
lua_pushinteger(L, posi + 1); /* ... and current position */
return 2;
}
posi = s1 - s;
n++;
}
lua_pushinteger(L, n);
return 1;
}
/*
** codepoint(s, [i, [j]]) -> returns codepoints for all characters
** that start in the range [i,j]
*/
static int codepoint (lua_State *L) {
size_t len;
const char *s = luaL_checklstring(L, 1, &len);
lua_Integer posi = u_posrelat(luaL_optinteger(L, 2, 1), len);
lua_Integer pose = u_posrelat(luaL_optinteger(L, 3, posi), len);
int n;
const char *se;
luaL_argcheck(L, posi >= 1, 2, "out of range");
luaL_argcheck(L, pose <= (lua_Integer)len, 3, "out of range");
if (posi > pose) return 0; /* empty interval; return no values */
n = (int)(pose - posi + 1);
if (posi + n <= pose) /* (lua_Integer -> int) overflow? */
return luaL_error(L, "string slice too long");
luaL_checkstack(L, n, "string slice too long");
n = 0;
se = s + pose;
for (s += posi - 1; s < se;) {
int code;
s = utf8_decode(s, &code);
if (s == NULL)
return luaL_error(L, "invalid UTF-8 code");
lua_pushinteger(L, code);
n++;
}
return n;
}
static void pushutfchar (lua_State *L, int arg) {
lua_Integer code = luaL_checkinteger(L, arg);
luaL_argcheck(L, 0 <= code && code <= MAXUNICODE, arg, "value out of range");
lua_pushfstring(L, "%U", (long)code);
}
/*
** utfchar(n1, n2, ...) -> char(n1)..char(n2)...
*/
static int utfchar (lua_State *L) {
int n = lua_gettop(L); /* number of arguments */
if (n == 1) /* optimize common case of single char */
pushutfchar(L, 1);
else {
int i;
luaL_Buffer b;
luaL_buffinit(L, &b);
for (i = 1; i <= n; i++) {
pushutfchar(L, i);
luaL_addvalue(&b);
}
luaL_pushresult(&b);
}
return 1;
}
/*
** offset(s, n, [i]) -> index where n-th character counting from
** position 'i' starts; 0 means character at 'i'.
*/
static int byteoffset (lua_State *L) {
size_t len;
const char *s = luaL_checklstring(L, 1, &len);
lua_Integer n = luaL_checkinteger(L, 2);
lua_Integer posi = (n >= 0) ? 1 : len + 1;
posi = u_posrelat(luaL_optinteger(L, 3, posi), len);
luaL_argcheck(L, 1 <= posi && --posi <= (lua_Integer)len, 3,
"position out of range");
if (n == 0) {
/* find beginning of current byte sequence */
while (posi > 0 && iscont(s + posi)) posi--;
}
else {
if (iscont(s + posi))
luaL_error(L, "initial position is a continuation byte");
if (n < 0) {
while (n < 0 && posi > 0) { /* move back */
do { /* find beginning of previous character */
posi--;
} while (posi > 0 && iscont(s + posi));
n++;
}
}
else {
n--; /* do not move for 1st character */
while (n > 0 && posi < (lua_Integer)len) {
do { /* find beginning of next character */
posi++;
} while (iscont(s + posi)); /* (cannot pass final '\0') */
n--;
}
}
}
if (n == 0) /* did it find given character? */
lua_pushinteger(L, posi + 1);
else /* no such character */
lua_pushnil(L);
return 1;
}
static int iter_aux (lua_State *L) {
size_t len;
const char *s = luaL_checklstring(L, 1, &len);
lua_Integer n = lua_tointeger(L, 2) - 1;
if (n < 0) /* first iteration? */
n = 0; /* start from here */
else if (n < (lua_Integer)len) {
n++; /* skip current byte */
while (iscont(s + n)) n++; /* and its continuations */
}
if (n >= (lua_Integer)len)
return 0; /* no more codepoints */
else {
int code;
const char *next = utf8_decode(s + n, &code);
if (next == NULL || iscont(next))
return luaL_error(L, "invalid UTF-8 code");
lua_pushinteger(L, n + 1);
lua_pushinteger(L, code);
return 2;
}
}
static int iter_codes (lua_State *L) {
luaL_checkstring(L, 1);
lua_pushcfunction(L, iter_aux);
lua_pushvalue(L, 1);
lua_pushinteger(L, 0);
return 3;
}
/* pattern to match a single UTF-8 character */
#define UTF8PATT "[\0-\x7F\xC2-\xF4][\x80-\xBF]*"
static struct luaL_Reg funcs[] = {
{"offset", byteoffset},
{"codepoint", codepoint},
{"char", utfchar},
{"len", utflen},
{"codes", iter_codes},
/* placeholders */
{"charpattern", NULL},
{NULL, NULL}
};
LUAMOD_API int luaopen_utf8 (lua_State *L) {
luaL_newlib(L, funcs);
lua_pushliteral(L, UTF8PATT);
lua_setfield(L, -2, "charpattern");
return 1;
}