lite-xl/src/api/regex.c

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#include "api.h"
#define PCRE2_CODE_UNIT_WIDTH 8
#include <string.h>
#include <pcre2.h>
static int f_pcre_gc(lua_State* L) {
lua_rawgeti(L, -1, 1);
pcre2_code* re = (pcre2_code*)lua_touserdata(L, -1);
if (re)
pcre2_code_free(re);
return 0;
}
static int f_pcre_compile(lua_State *L) {
size_t len;
PCRE2_SIZE errorOffset;
int errorNumber;
int pattern = PCRE2_UTF;
const char* str = luaL_checklstring(L, 1, &len);
if (lua_gettop(L) > 1) {
const char* options = luaL_checkstring(L, 2);
if (strstr(options,"i"))
pattern |= PCRE2_CASELESS;
if (strstr(options,"m"))
pattern |= PCRE2_MULTILINE;
if (strstr(options,"s"))
pattern |= PCRE2_DOTALL;
}
pcre2_code* re = pcre2_compile(
(PCRE2_SPTR)str,
len,
pattern,
&errorNumber,
&errorOffset,
NULL
);
if (re) {
lua_newtable(L);
lua_pushlightuserdata(L, re);
lua_rawseti(L, -2, 1);
luaL_setmetatable(L, "regex");
return 1;
}
PCRE2_UCHAR buffer[256];
pcre2_get_error_message(errorNumber, buffer, sizeof(buffer));
lua_pushnil(L);
char message[1024];
len = snprintf(message, sizeof(message), "regex compilation failed at offset %d: %s", (int)errorOffset, buffer);
lua_pushlstring(L, message, len);
return 2;
}
// Takes string, compiled regex, returns list of indices of matched groups
// (including the whole match), if a match was found.
static int f_pcre_match(lua_State *L) {
size_t len, offset = 1, opts = 0;
luaL_checktype(L, 1, LUA_TTABLE);
const char* str = luaL_checklstring(L, 2, &len);
if (lua_gettop(L) > 2)
offset = luaL_checknumber(L, 3);
if (lua_gettop(L) > 3)
opts = luaL_checknumber(L, 4);
lua_rawgeti(L, 1, 1);
pcre2_code* re = (pcre2_code*)lua_touserdata(L, -1);
pcre2_match_data* md = pcre2_match_data_create_from_pattern(re, NULL);
int rc = pcre2_match(re, (PCRE2_SPTR)str, len, offset - 1, opts, md, NULL);
if (rc < 0) {
pcre2_match_data_free(md);
if (rc != PCRE2_ERROR_NOMATCH) {
PCRE2_UCHAR buffer[120];
pcre2_get_error_message(rc, buffer, sizeof(buffer));
luaL_error(L, "regex matching error %d: %s", rc, buffer);
}
return 0;
}
PCRE2_SIZE* ovector = pcre2_get_ovector_pointer(md);
if (ovector[0] > ovector[1]) {
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/* We must guard against patterns such as /(?=.\K)/ that use \K in an
assertion to set the start of a match later than its end. In the editor,
we just detect this case and give up. */
luaL_error(L, "regex matching error: \\K was used in an assertion to "
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" set the match start after its end");
pcre2_match_data_free(md);
return 0;
}
for (int i = 0; i < rc*2; i++)
lua_pushnumber(L, ovector[i]+1);
pcre2_match_data_free(md);
return rc*2;
}
static const luaL_Reg lib[] = {
{ "compile", f_pcre_compile },
{ "cmatch", f_pcre_match },
{ "__gc", f_pcre_gc },
{ NULL, NULL }
};
int luaopen_regex(lua_State *L) {
luaL_newlib(L, lib);
lua_pushliteral(L, "regex");
lua_setfield(L, -2, "__name");
lua_pushvalue(L, -1);
lua_setfield(L, LUA_REGISTRYINDEX, "regex");
lua_pushnumber(L, PCRE2_ANCHORED);
lua_setfield(L, -2, "ANCHORED");
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lua_pushnumber(L, PCRE2_ANCHORED) ;
lua_setfield(L, -2, "ENDANCHORED");
lua_pushnumber(L, PCRE2_NOTBOL);
lua_setfield(L, -2, "NOTBOL");
lua_pushnumber(L, PCRE2_NOTEOL);
lua_setfield(L, -2, "NOTEOL");
lua_pushnumber(L, PCRE2_NOTEMPTY);
lua_setfield(L, -2, "NOTEMPTY");
lua_pushnumber(L, PCRE2_NOTEMPTY_ATSTART);
lua_setfield(L, -2, "NOTEMPTY_ATSTART");
return 1;
}