+++ /dev/null
-/*
-** $Id: lutf8lib.c,v 1.15 2015/03/28 19:16:55 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 <limits.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 const 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 */
- if (pose - posi >= INT_MAX) /* (lua_Integer -> int) overflow? */
- return luaL_error(L, "string slice too long");
- n = (int)(pose - posi) + 1;
- 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 const 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_pushlstring(L, UTF8PATT, sizeof(UTF8PATT)/sizeof(char) - 1);
- lua_setfield(L, -2, "charpattern");
- return 1;
-}
-
projects / ceph.git / blobdiff