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	Unfortunately macOS has obj-C keyword "fallthrough" in the OS headers. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Damian Szuberski <szuberskidamian@gmail.com> Signed-off-by: Jorgen Lundman <lundman@lundman.net> Closes #13097
		
			
				
	
	
		
			1039 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			1039 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
** $Id: lstrlib.c,v 1.178.1.1 2013/04/12 18:48:47 roberto Exp $
 | 
						|
** Standard library for string operations and pattern-matching
 | 
						|
** See Copyright Notice in lua.h
 | 
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*/
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 | 
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 | 
						|
#define lstrlib_c
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#define LUA_LIB
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#include <sys/lua/lua.h>
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 | 
						|
#include <sys/lua/lauxlib.h>
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#include <sys/lua/lualib.h>
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 | 
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/*
 | 
						|
** maximum number of captures that a pattern can do during
 | 
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** pattern-matching. This limit is arbitrary.
 | 
						|
*/
 | 
						|
#if !defined(LUA_MAXCAPTURES)
 | 
						|
#define LUA_MAXCAPTURES		16
 | 
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#endif
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 | 
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/* macro to `unsign' a character */
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						|
#define uchar(c)	((unsigned char)(c))
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 | 
						|
/*
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						|
 * The provided version of sprintf returns a char *, but str_format expects
 | 
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 * it to return the number of characters printed. This version has the expected
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 * behavior.
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 */
 | 
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static size_t str_sprintf(char *buf, const char *fmt, ...) {
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						|
  va_list args;
 | 
						|
  size_t len;
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 | 
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  va_start(args, fmt);
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						|
  len = vsnprintf(buf, INT_MAX, fmt, args);
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  va_end(args);
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 | 
						|
  return len;
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}
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 | 
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static int str_len (lua_State *L) {
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						|
  size_t l;
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						|
  luaL_checklstring(L, 1, &l);
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  lua_pushinteger(L, (lua_Integer)l);
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  return 1;
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}
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 | 
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/* translate a relative string position: negative means back from end */
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static size_t posrelat (ptrdiff_t pos, size_t len) {
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						|
  if (pos >= 0) return (size_t)pos;
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  else if (0u - (size_t)pos > len) return 0;
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  else return len - ((size_t)-pos) + 1;
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}
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 | 
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static int str_sub (lua_State *L) {
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						|
  size_t l;
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  const char *s = luaL_checklstring(L, 1, &l);
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  size_t start = posrelat(luaL_checkinteger(L, 2), l);
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						|
  size_t end = posrelat(luaL_optinteger(L, 3, -1), l);
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  if (start < 1) start = 1;
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  if (end > l) end = l;
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  if (start <= end)
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    lua_pushlstring(L, s + start - 1, end - start + 1);
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  else lua_pushliteral(L, "");
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  return 1;
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}
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static int str_reverse (lua_State *L) {
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						|
  size_t l, i;
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						|
  luaL_Buffer b;
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  const char *s = luaL_checklstring(L, 1, &l);
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  char *p = luaL_buffinitsize(L, &b, l);
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  for (i = 0; i < l; i++)
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    p[i] = s[l - i - 1];
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  luaL_pushresultsize(&b, l);
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  return 1;
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}
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static int str_lower (lua_State *L) {
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						|
  size_t l;
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  size_t i;
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  luaL_Buffer b;
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  const char *s = luaL_checklstring(L, 1, &l);
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  char *p = luaL_buffinitsize(L, &b, l);
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  for (i=0; i<l; i++)
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    p[i] = tolower(uchar(s[i]));
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  luaL_pushresultsize(&b, l);
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  return 1;
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}
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 | 
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static int str_upper (lua_State *L) {
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  size_t l;
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  size_t i;
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  luaL_Buffer b;
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  const char *s = luaL_checklstring(L, 1, &l);
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  char *p = luaL_buffinitsize(L, &b, l);
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  for (i=0; i<l; i++)
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    p[i] = toupper(uchar(s[i]));
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  luaL_pushresultsize(&b, l);
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  return 1;
 | 
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}
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/* reasonable limit to avoid arithmetic overflow */
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#define MAXSIZE		((~(size_t)0) >> 1)
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 | 
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static int str_rep (lua_State *L) {
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  size_t l, lsep;
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  const char *s = luaL_checklstring(L, 1, &l);
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  int n = luaL_checkint(L, 2);
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  const char *sep = luaL_optlstring(L, 3, "", &lsep);
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  if (n <= 0) lua_pushliteral(L, "");
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  else if (l + lsep < l || l + lsep >= MAXSIZE / n)  /* may overflow? */
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    return luaL_error(L, "resulting string too large");
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  else {
 | 
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    size_t totallen = n * l + (n - 1) * lsep;
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    luaL_Buffer b;
 | 
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    char *p = luaL_buffinitsize(L, &b, totallen);
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    while (n-- > 1) {  /* first n-1 copies (followed by separator) */
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      memcpy(p, s, l * sizeof(char)); p += l;
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      if (lsep > 0) {  /* avoid empty 'memcpy' (may be expensive) */
 | 
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        memcpy(p, sep, lsep * sizeof(char)); p += lsep;
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      }
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    }
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    memcpy(p, s, l * sizeof(char));  /* last copy (not followed by separator) */
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    luaL_pushresultsize(&b, totallen);
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  }
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  return 1;
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}
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static int str_byte (lua_State *L) {
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  size_t l;
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  const char *s = luaL_checklstring(L, 1, &l);
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  size_t posi = posrelat(luaL_optinteger(L, 2, 1), l);
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  size_t pose = posrelat(luaL_optinteger(L, 3, posi), l);
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  int n, i;
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  if (posi < 1) posi = 1;
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  if (pose > l) pose = l;
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  if (posi > pose) return 0;  /* empty interval; return no values */
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  n = (int)(pose -  posi + 1);
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  if (posi + n <= pose)  /* (size_t -> int) overflow? */
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    return luaL_error(L, "string slice too long");
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  luaL_checkstack(L, n, "string slice too long");
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  for (i=0; i<n; i++)
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    lua_pushinteger(L, uchar(s[posi+i-1]));
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  return n;
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}
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static int str_char (lua_State *L) {
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  int n = lua_gettop(L);  /* number of arguments */
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  int i;
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  luaL_Buffer b;
 | 
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  char *p = luaL_buffinitsize(L, &b, n);
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  for (i=1; i<=n; i++) {
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    int c = luaL_checkint(L, i);
 | 
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    luaL_argcheck(L, uchar(c) == c, i, "value out of range");
 | 
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    p[i - 1] = uchar(c);
 | 
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  }
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  luaL_pushresultsize(&b, n);
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  return 1;
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}
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#if defined(LUA_USE_DUMP)
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static int writer (lua_State *L, const void* b, size_t size, void* B) {
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  (void)L;
 | 
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  luaL_addlstring((luaL_Buffer*) B, (const char *)b, size);
 | 
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  return 0;
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}
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static int str_dump (lua_State *L) {
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  luaL_Buffer b;
 | 
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  luaL_checktype(L, 1, LUA_TFUNCTION);
 | 
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  lua_settop(L, 1);
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  luaL_buffinit(L,&b);
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  if (lua_dump(L, writer, &b) != 0)
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    return luaL_error(L, "unable to dump given function");
 | 
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  luaL_pushresult(&b);
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  return 1;
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}
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#endif
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/*
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** {======================================================
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** PATTERN MATCHING
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** =======================================================
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*/
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#define CAP_UNFINISHED	(-1)
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#define CAP_POSITION	(-2)
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typedef struct MatchState {
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  int matchdepth;  /* control for recursive depth (to avoid C stack overflow) */
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  const char *src_init;  /* init of source string */
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  const char *src_end;  /* end ('\0') of source string */
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  const char *p_end;  /* end ('\0') of pattern */
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  lua_State *L;
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  int level;  /* total number of captures (finished or unfinished) */
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  struct {
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    const char *init;
 | 
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    ptrdiff_t len;
 | 
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  } capture[LUA_MAXCAPTURES];
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} MatchState;
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/* recursive function */
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static const char *match (MatchState *ms, const char *s, const char *p);
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/* maximum recursion depth for 'match' */
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#if !defined(MAXCCALLS)
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#define MAXCCALLS	200
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#endif
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#define L_ESC		'%'
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#define SPECIALS	"^$*+?.([%-"
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static int check_capture (MatchState *ms, int l) {
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  l -= '1';
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  if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
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    return luaL_error(ms->L, "invalid capture index %%%d", l + 1);
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  return l;
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}
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static int capture_to_close (MatchState *ms) {
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  int level = ms->level;
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  for (level--; level>=0; level--)
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    if (ms->capture[level].len == CAP_UNFINISHED) return level;
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  return luaL_error(ms->L, "invalid pattern capture");
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}
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static const char *classend (MatchState *ms, const char *p) {
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  switch (*p++) {
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    case L_ESC: {
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      if (p == ms->p_end)
 | 
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        luaL_error(ms->L, "malformed pattern (ends with " LUA_QL("%%") ")");
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      return p+1;
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    }
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    case '[': {
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      if (*p == '^') p++;
 | 
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      do {  /* look for a `]' */
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        if (p == ms->p_end)
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          luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")");
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        if (*(p++) == L_ESC && p < ms->p_end)
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          p++;  /* skip escapes (e.g. `%]') */
 | 
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      } while (*p != ']');
 | 
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      return p+1;
 | 
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    }
 | 
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    default: {
 | 
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      return p;
 | 
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    }
 | 
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  }
 | 
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}
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 | 
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static int match_class (int c, int cl) {
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						|
  int res;
 | 
						|
  switch (tolower(cl)) {
 | 
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    case 'a' : res = isalpha(c); break;
 | 
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    case 'c' : res = iscntrl(c); break;
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    case 'd' : res = isdigit(c); break;
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    case 'g' : res = isgraph(c); break;
 | 
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    case 'l' : res = islower(c); break;
 | 
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    case 'p' : res = ispunct(c); break;
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    case 's' : res = isspace(c); break;
 | 
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    case 'u' : res = isupper(c); break;
 | 
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    case 'w' : res = isalnum(c); break;
 | 
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    case 'x' : res = isxdigit(c); break;
 | 
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    case 'z' : res = (c == 0); break;  /* deprecated option */
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    default: return (cl == c);
 | 
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  }
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  return (islower(cl) ? res : !res);
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}
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static int matchbracketclass (int c, const char *p, const char *ec) {
 | 
						|
  int sig = 1;
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  if (*(p+1) == '^') {
 | 
						|
    sig = 0;
 | 
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    p++;  /* skip the `^' */
 | 
						|
  }
 | 
						|
  while (++p < ec) {
 | 
						|
    if (*p == L_ESC) {
 | 
						|
      p++;
 | 
						|
      if (match_class(c, uchar(*p)))
 | 
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        return sig;
 | 
						|
    }
 | 
						|
    else if ((*(p+1) == '-') && (p+2 < ec)) {
 | 
						|
      p+=2;
 | 
						|
      if (uchar(*(p-2)) <= c && c <= uchar(*p))
 | 
						|
        return sig;
 | 
						|
    }
 | 
						|
    else if (uchar(*p) == c) return sig;
 | 
						|
  }
 | 
						|
  return !sig;
 | 
						|
}
 | 
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 | 
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 | 
						|
static int singlematch (MatchState *ms, const char *s, const char *p,
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						|
                        const char *ep) {
 | 
						|
  if (s >= ms->src_end)
 | 
						|
    return 0;
 | 
						|
  else {
 | 
						|
    int c = uchar(*s);
 | 
						|
    switch (*p) {
 | 
						|
      case '.': return 1;  /* matches any char */
 | 
						|
      case L_ESC: return match_class(c, uchar(*(p+1)));
 | 
						|
      case '[': return matchbracketclass(c, p, ep-1);
 | 
						|
      default:  return (uchar(*p) == c);
 | 
						|
    }
 | 
						|
  }
 | 
						|
}
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 | 
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 | 
						|
static const char *matchbalance (MatchState *ms, const char *s,
 | 
						|
                                   const char *p) {
 | 
						|
  if (p >= ms->p_end - 1)
 | 
						|
    luaL_error(ms->L, "malformed pattern "
 | 
						|
                      "(missing arguments to " LUA_QL("%%b") ")");
 | 
						|
  if (*s != *p) return NULL;
 | 
						|
  else {
 | 
						|
    int b = *p;
 | 
						|
    int e = *(p+1);
 | 
						|
    int cont = 1;
 | 
						|
    while (++s < ms->src_end) {
 | 
						|
      if (*s == e) {
 | 
						|
        if (--cont == 0) return s+1;
 | 
						|
      }
 | 
						|
      else if (*s == b) cont++;
 | 
						|
    }
 | 
						|
  }
 | 
						|
  return NULL;  /* string ends out of balance */
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static const char *max_expand (MatchState *ms, const char *s,
 | 
						|
                                 const char *p, const char *ep) {
 | 
						|
  ptrdiff_t i = 0;  /* counts maximum expand for item */
 | 
						|
  while (singlematch(ms, s + i, p, ep))
 | 
						|
    i++;
 | 
						|
  /* keeps trying to match with the maximum repetitions */
 | 
						|
  while (i>=0) {
 | 
						|
    const char *res = match(ms, (s+i), ep+1);
 | 
						|
    if (res) return res;
 | 
						|
    i--;  /* else didn't match; reduce 1 repetition to try again */
 | 
						|
  }
 | 
						|
  return NULL;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static const char *min_expand (MatchState *ms, const char *s,
 | 
						|
                                 const char *p, const char *ep) {
 | 
						|
  for (;;) {
 | 
						|
    const char *res = match(ms, s, ep+1);
 | 
						|
    if (res != NULL)
 | 
						|
      return res;
 | 
						|
    else if (singlematch(ms, s, p, ep))
 | 
						|
      s++;  /* try with one more repetition */
 | 
						|
    else return NULL;
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static const char *start_capture (MatchState *ms, const char *s,
 | 
						|
                                    const char *p, int what) {
 | 
						|
  const char *res;
 | 
						|
  int level = ms->level;
 | 
						|
  if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
 | 
						|
  ms->capture[level].init = s;
 | 
						|
  ms->capture[level].len = what;
 | 
						|
  ms->level = level+1;
 | 
						|
  if ((res=match(ms, s, p)) == NULL)  /* match failed? */
 | 
						|
    ms->level--;  /* undo capture */
 | 
						|
  return res;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static const char *end_capture (MatchState *ms, const char *s,
 | 
						|
                                  const char *p) {
 | 
						|
  int l = capture_to_close(ms);
 | 
						|
  const char *res;
 | 
						|
  ms->capture[l].len = s - ms->capture[l].init;  /* close capture */
 | 
						|
  if ((res = match(ms, s, p)) == NULL)  /* match failed? */
 | 
						|
    ms->capture[l].len = CAP_UNFINISHED;  /* undo capture */
 | 
						|
  return res;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static const char *match_capture (MatchState *ms, const char *s, int l) {
 | 
						|
  size_t len;
 | 
						|
  l = check_capture(ms, l);
 | 
						|
  len = ms->capture[l].len;
 | 
						|
  if ((size_t)(ms->src_end-s) >= len &&
 | 
						|
      memcmp(ms->capture[l].init, s, len) == 0)
 | 
						|
    return s+len;
 | 
						|
  else return NULL;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static const char *match (MatchState *ms, const char *s, const char *p) {
 | 
						|
  if (ms->matchdepth-- == 0)
 | 
						|
    luaL_error(ms->L, "pattern too complex");
 | 
						|
  init: /* using goto's to optimize tail recursion */
 | 
						|
  if (p != ms->p_end) {  /* end of pattern? */
 | 
						|
    switch (*p) {
 | 
						|
      case '(': {  /* start capture */
 | 
						|
        if (*(p + 1) == ')')  /* position capture? */
 | 
						|
          s = start_capture(ms, s, p + 2, CAP_POSITION);
 | 
						|
        else
 | 
						|
          s = start_capture(ms, s, p + 1, CAP_UNFINISHED);
 | 
						|
        break;
 | 
						|
      }
 | 
						|
      case ')': {  /* end capture */
 | 
						|
        s = end_capture(ms, s, p + 1);
 | 
						|
        break;
 | 
						|
      }
 | 
						|
      case '$': {
 | 
						|
        if ((p + 1) != ms->p_end)  /* is the `$' the last char in pattern? */
 | 
						|
          goto dflt;  /* no; go to default */
 | 
						|
        s = (s == ms->src_end) ? s : NULL;  /* check end of string */
 | 
						|
        break;
 | 
						|
      }
 | 
						|
      case L_ESC: {  /* escaped sequences not in the format class[*+?-]? */
 | 
						|
        switch (*(p + 1)) {
 | 
						|
          case 'b': {  /* balanced string? */
 | 
						|
            s = matchbalance(ms, s, p + 2);
 | 
						|
            if (s != NULL) {
 | 
						|
              p += 4; goto init;  /* return match(ms, s, p + 4); */
 | 
						|
            }  /* else fail (s == NULL) */
 | 
						|
            break;
 | 
						|
          }
 | 
						|
          case 'f': {  /* frontier? */
 | 
						|
            const char *ep; char previous;
 | 
						|
            p += 2;
 | 
						|
            if (*p != '[')
 | 
						|
              luaL_error(ms->L, "missing " LUA_QL("[") " after "
 | 
						|
                                 LUA_QL("%%f") " in pattern");
 | 
						|
            ep = classend(ms, p);  /* points to what is next */
 | 
						|
            previous = (s == ms->src_init) ? '\0' : *(s - 1);
 | 
						|
            if (!matchbracketclass(uchar(previous), p, ep - 1) &&
 | 
						|
               matchbracketclass(uchar(*s), p, ep - 1)) {
 | 
						|
              p = ep; goto init;  /* return match(ms, s, ep); */
 | 
						|
            }
 | 
						|
            s = NULL;  /* match failed */
 | 
						|
            break;
 | 
						|
          }
 | 
						|
          case '0': case '1': case '2': case '3':
 | 
						|
          case '4': case '5': case '6': case '7':
 | 
						|
          case '8': case '9': {  /* capture results (%0-%9)? */
 | 
						|
            s = match_capture(ms, s, uchar(*(p + 1)));
 | 
						|
            if (s != NULL) {
 | 
						|
              p += 2; goto init;  /* return match(ms, s, p + 2) */
 | 
						|
            }
 | 
						|
            break;
 | 
						|
          }
 | 
						|
          default: goto dflt;
 | 
						|
        }
 | 
						|
        break;
 | 
						|
      }
 | 
						|
      default: dflt: {  /* pattern class plus optional suffix */
 | 
						|
        const char *ep = classend(ms, p);  /* points to optional suffix */
 | 
						|
        /* does not match at least once? */
 | 
						|
        if (!singlematch(ms, s, p, ep)) {
 | 
						|
          if (*ep == '*' || *ep == '?' || *ep == '-') {  /* accept empty? */
 | 
						|
            p = ep + 1; goto init;  /* return match(ms, s, ep + 1); */
 | 
						|
          }
 | 
						|
          else  /* '+' or no suffix */
 | 
						|
            s = NULL;  /* fail */
 | 
						|
        }
 | 
						|
        else {  /* matched once */
 | 
						|
          switch (*ep) {  /* handle optional suffix */
 | 
						|
            case '?': {  /* optional */
 | 
						|
              const char *res;
 | 
						|
              if ((res = match(ms, s + 1, ep + 1)) != NULL)
 | 
						|
                s = res;
 | 
						|
              else {
 | 
						|
                p = ep + 1; goto init;  /* else return match(ms, s, ep + 1); */
 | 
						|
              }
 | 
						|
              break;
 | 
						|
            }
 | 
						|
            case '+':  /* 1 or more repetitions */
 | 
						|
              s++;  /* 1 match already done */
 | 
						|
              zfs_fallthrough;
 | 
						|
            case '*':  /* 0 or more repetitions */
 | 
						|
              s = max_expand(ms, s, p, ep);
 | 
						|
              break;
 | 
						|
            case '-':  /* 0 or more repetitions (minimum) */
 | 
						|
              s = min_expand(ms, s, p, ep);
 | 
						|
              break;
 | 
						|
            default:  /* no suffix */
 | 
						|
              s++; p = ep; goto init;  /* return match(ms, s + 1, ep); */
 | 
						|
          }
 | 
						|
        }
 | 
						|
        break;
 | 
						|
      }
 | 
						|
    }
 | 
						|
  }
 | 
						|
  ms->matchdepth++;
 | 
						|
  return s;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
 | 
						|
static const char *lmemfind (const char *s1, size_t l1,
 | 
						|
                               const char *s2, size_t l2) {
 | 
						|
  if (l2 == 0) return s1;  /* empty strings are everywhere */
 | 
						|
  else if (l2 > l1) return NULL;  /* avoids a negative `l1' */
 | 
						|
  else {
 | 
						|
    const char *init;  /* to search for a `*s2' inside `s1' */
 | 
						|
    l2--;  /* 1st char will be checked by `memchr' */
 | 
						|
    l1 = l1-l2;  /* `s2' cannot be found after that */
 | 
						|
    while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
 | 
						|
      init++;   /* 1st char is already checked */
 | 
						|
      if (memcmp(init, s2+1, l2) == 0)
 | 
						|
        return init-1;
 | 
						|
      else {  /* correct `l1' and `s1' to try again */
 | 
						|
        l1 -= init-s1;
 | 
						|
        s1 = init;
 | 
						|
      }
 | 
						|
    }
 | 
						|
    return NULL;  /* not found */
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static void push_onecapture (MatchState *ms, int i, const char *s,
 | 
						|
                                                    const char *e) {
 | 
						|
  if (i >= ms->level) {
 | 
						|
    if (i == 0)  /* ms->level == 0, too */
 | 
						|
      lua_pushlstring(ms->L, s, e - s);  /* add whole match */
 | 
						|
    else
 | 
						|
      luaL_error(ms->L, "invalid capture index");
 | 
						|
  }
 | 
						|
  else {
 | 
						|
    ptrdiff_t l = ms->capture[i].len;
 | 
						|
    if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture");
 | 
						|
    if (l == CAP_POSITION)
 | 
						|
      lua_pushinteger(ms->L, ms->capture[i].init - ms->src_init + 1);
 | 
						|
    else
 | 
						|
      lua_pushlstring(ms->L, ms->capture[i].init, l);
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int push_captures (MatchState *ms, const char *s, const char *e) {
 | 
						|
  int i;
 | 
						|
  int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
 | 
						|
  luaL_checkstack(ms->L, nlevels, "too many captures");
 | 
						|
  for (i = 0; i < nlevels; i++)
 | 
						|
    push_onecapture(ms, i, s, e);
 | 
						|
  return nlevels;  /* number of strings pushed */
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/* check whether pattern has no special characters */
 | 
						|
static int nospecials (const char *p, size_t l) {
 | 
						|
  size_t upto = 0;
 | 
						|
  do {
 | 
						|
    if (strpbrk(p + upto, SPECIALS))
 | 
						|
      return 0;  /* pattern has a special character */
 | 
						|
    upto += strlen(p + upto) + 1;  /* may have more after \0 */
 | 
						|
  } while (upto <= l);
 | 
						|
  return 1;  /* no special chars found */
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int str_find_aux (lua_State *L, int find) {
 | 
						|
  size_t ls, lp;
 | 
						|
  const char *s = luaL_checklstring(L, 1, &ls);
 | 
						|
  const char *p = luaL_checklstring(L, 2, &lp);
 | 
						|
  size_t init = posrelat(luaL_optinteger(L, 3, 1), ls);
 | 
						|
  if (init < 1) init = 1;
 | 
						|
  else if (init > ls + 1) {  /* start after string's end? */
 | 
						|
    lua_pushnil(L);  /* cannot find anything */
 | 
						|
    return 1;
 | 
						|
  }
 | 
						|
  /* explicit request or no special characters? */
 | 
						|
  if (find && (lua_toboolean(L, 4) || nospecials(p, lp))) {
 | 
						|
    /* do a plain search */
 | 
						|
    const char *s2 = lmemfind(s + init - 1, ls - init + 1, p, lp);
 | 
						|
    if (s2) {
 | 
						|
      lua_pushinteger(L, s2 - s + 1);
 | 
						|
      lua_pushinteger(L, s2 - s + lp);
 | 
						|
      return 2;
 | 
						|
    }
 | 
						|
  }
 | 
						|
  else {
 | 
						|
    MatchState ms;
 | 
						|
    const char *s1 = s + init - 1;
 | 
						|
    int anchor = (*p == '^');
 | 
						|
    if (anchor) {
 | 
						|
      p++; lp--;  /* skip anchor character */
 | 
						|
    }
 | 
						|
    ms.L = L;
 | 
						|
    ms.matchdepth = MAXCCALLS;
 | 
						|
    ms.src_init = s;
 | 
						|
    ms.src_end = s + ls;
 | 
						|
    ms.p_end = p + lp;
 | 
						|
    do {
 | 
						|
      const char *res;
 | 
						|
      ms.level = 0;
 | 
						|
      lua_assert(ms.matchdepth == MAXCCALLS);
 | 
						|
      if ((res=match(&ms, s1, p)) != NULL) {
 | 
						|
        if (find) {
 | 
						|
          lua_pushinteger(L, s1 - s + 1);  /* start */
 | 
						|
          lua_pushinteger(L, res - s);   /* end */
 | 
						|
          return push_captures(&ms, NULL, 0) + 2;
 | 
						|
        }
 | 
						|
        else
 | 
						|
          return push_captures(&ms, s1, res);
 | 
						|
      }
 | 
						|
    } while (s1++ < ms.src_end && !anchor);
 | 
						|
  }
 | 
						|
  lua_pushnil(L);  /* not found */
 | 
						|
  return 1;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int str_find (lua_State *L) {
 | 
						|
  return str_find_aux(L, 1);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int str_match (lua_State *L) {
 | 
						|
  return str_find_aux(L, 0);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int gmatch_aux (lua_State *L) {
 | 
						|
  MatchState ms;
 | 
						|
  size_t ls, lp;
 | 
						|
  const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls);
 | 
						|
  const char *p = lua_tolstring(L, lua_upvalueindex(2), &lp);
 | 
						|
  const char *src;
 | 
						|
  ms.L = L;
 | 
						|
  ms.matchdepth = MAXCCALLS;
 | 
						|
  ms.src_init = s;
 | 
						|
  ms.src_end = s+ls;
 | 
						|
  ms.p_end = p + lp;
 | 
						|
  for (src = s + (size_t)lua_tointeger(L, lua_upvalueindex(3));
 | 
						|
       src <= ms.src_end;
 | 
						|
       src++) {
 | 
						|
    const char *e;
 | 
						|
    ms.level = 0;
 | 
						|
    lua_assert(ms.matchdepth == MAXCCALLS);
 | 
						|
    if ((e = match(&ms, src, p)) != NULL) {
 | 
						|
      lua_Integer newstart = e-s;
 | 
						|
      if (e == src) newstart++;  /* empty match? go at least one position */
 | 
						|
      lua_pushinteger(L, newstart);
 | 
						|
      lua_replace(L, lua_upvalueindex(3));
 | 
						|
      return push_captures(&ms, src, e);
 | 
						|
    }
 | 
						|
  }
 | 
						|
  return 0;  /* not found */
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int str_gmatch (lua_State *L) {
 | 
						|
  luaL_checkstring(L, 1);
 | 
						|
  luaL_checkstring(L, 2);
 | 
						|
  lua_settop(L, 2);
 | 
						|
  lua_pushinteger(L, 0);
 | 
						|
  lua_pushcclosure(L, gmatch_aux, 3);
 | 
						|
  return 1;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
 | 
						|
                                                   const char *e) {
 | 
						|
  size_t l, i;
 | 
						|
  const char *news = lua_tolstring(ms->L, 3, &l);
 | 
						|
  for (i = 0; i < l; i++) {
 | 
						|
    if (news[i] != L_ESC)
 | 
						|
      luaL_addchar(b, news[i]);
 | 
						|
    else {
 | 
						|
      i++;  /* skip ESC */
 | 
						|
      if (!isdigit(uchar(news[i]))) {
 | 
						|
        if (news[i] != L_ESC)
 | 
						|
          luaL_error(ms->L, "invalid use of " LUA_QL("%c")
 | 
						|
                           " in replacement string", L_ESC);
 | 
						|
        luaL_addchar(b, news[i]);
 | 
						|
      }
 | 
						|
      else if (news[i] == '0')
 | 
						|
          luaL_addlstring(b, s, e - s);
 | 
						|
      else {
 | 
						|
        push_onecapture(ms, news[i] - '1', s, e);
 | 
						|
        luaL_addvalue(b);  /* add capture to accumulated result */
 | 
						|
      }
 | 
						|
    }
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
 | 
						|
                                       const char *e, int tr) {
 | 
						|
  lua_State *L = ms->L;
 | 
						|
  switch (tr) {
 | 
						|
    case LUA_TFUNCTION: {
 | 
						|
      int n;
 | 
						|
      lua_pushvalue(L, 3);
 | 
						|
      n = push_captures(ms, s, e);
 | 
						|
      lua_call(L, n, 1);
 | 
						|
      break;
 | 
						|
    }
 | 
						|
    case LUA_TTABLE: {
 | 
						|
      push_onecapture(ms, 0, s, e);
 | 
						|
      lua_gettable(L, 3);
 | 
						|
      break;
 | 
						|
    }
 | 
						|
    default: {  /* LUA_TNUMBER or LUA_TSTRING */
 | 
						|
      add_s(ms, b, s, e);
 | 
						|
      return;
 | 
						|
    }
 | 
						|
  }
 | 
						|
  if (!lua_toboolean(L, -1)) {  /* nil or false? */
 | 
						|
    lua_pop(L, 1);
 | 
						|
    lua_pushlstring(L, s, e - s);  /* keep original text */
 | 
						|
  }
 | 
						|
  else if (!lua_isstring(L, -1))
 | 
						|
    luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1));
 | 
						|
  luaL_addvalue(b);  /* add result to accumulator */
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int str_gsub (lua_State *L) {
 | 
						|
  size_t srcl, lp;
 | 
						|
  const char *src = luaL_checklstring(L, 1, &srcl);
 | 
						|
  const char *p = luaL_checklstring(L, 2, &lp);
 | 
						|
  int tr = lua_type(L, 3);
 | 
						|
  size_t max_s = luaL_optinteger(L, 4, srcl+1);
 | 
						|
  int anchor = (*p == '^');
 | 
						|
  size_t n = 0;
 | 
						|
  MatchState ms;
 | 
						|
  luaL_Buffer b;
 | 
						|
  luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
 | 
						|
                   tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
 | 
						|
                      "string/function/table expected");
 | 
						|
  luaL_buffinit(L, &b);
 | 
						|
  if (anchor) {
 | 
						|
    p++; lp--;  /* skip anchor character */
 | 
						|
  }
 | 
						|
  ms.L = L;
 | 
						|
  ms.matchdepth = MAXCCALLS;
 | 
						|
  ms.src_init = src;
 | 
						|
  ms.src_end = src+srcl;
 | 
						|
  ms.p_end = p + lp;
 | 
						|
  while (n < max_s) {
 | 
						|
    const char *e;
 | 
						|
    ms.level = 0;
 | 
						|
    lua_assert(ms.matchdepth == MAXCCALLS);
 | 
						|
    e = match(&ms, src, p);
 | 
						|
    if (e) {
 | 
						|
      n++;
 | 
						|
      add_value(&ms, &b, src, e, tr);
 | 
						|
    }
 | 
						|
    if (e && e>src) /* non empty match? */
 | 
						|
      src = e;  /* skip it */
 | 
						|
    else if (src < ms.src_end)
 | 
						|
      luaL_addchar(&b, *src++);
 | 
						|
    else break;
 | 
						|
    if (anchor) break;
 | 
						|
  }
 | 
						|
  luaL_addlstring(&b, src, ms.src_end-src);
 | 
						|
  luaL_pushresult(&b);
 | 
						|
  lua_pushinteger(L, n);  /* number of substitutions */
 | 
						|
  return 2;
 | 
						|
}
 | 
						|
 | 
						|
/* }====================================================== */
 | 
						|
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
** {======================================================
 | 
						|
** STRING FORMAT
 | 
						|
** =======================================================
 | 
						|
*/
 | 
						|
 | 
						|
/*
 | 
						|
** LUA_INTFRMLEN is the length modifier for integer conversions in
 | 
						|
** 'string.format'; LUA_INTFRM_T is the integer type corresponding to
 | 
						|
** the previous length
 | 
						|
*/
 | 
						|
#if !defined(LUA_INTFRMLEN)	/* { */
 | 
						|
#if defined(LUA_USE_LONGLONG)
 | 
						|
 | 
						|
#define LUA_INTFRMLEN		"ll"
 | 
						|
#define LUA_INTFRM_T		long long
 | 
						|
 | 
						|
#else
 | 
						|
 | 
						|
#define LUA_INTFRMLEN		"l"
 | 
						|
#define LUA_INTFRM_T		long
 | 
						|
 | 
						|
#endif
 | 
						|
#endif				/* } */
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
** LUA_FLTFRMLEN is the length modifier for float conversions in
 | 
						|
** 'string.format'; LUA_FLTFRM_T is the float type corresponding to
 | 
						|
** the previous length
 | 
						|
*/
 | 
						|
#if !defined(LUA_FLTFRMLEN)
 | 
						|
 | 
						|
#define LUA_FLTFRMLEN		""
 | 
						|
#define LUA_FLTFRM_T		double
 | 
						|
 | 
						|
#endif
 | 
						|
 | 
						|
 | 
						|
/* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
 | 
						|
#define MAX_ITEM	512
 | 
						|
/* valid flags in a format specification */
 | 
						|
#define FLAGS	"-+ #0"
 | 
						|
/*
 | 
						|
** maximum size of each format specification (such as '%-099.99d')
 | 
						|
** (+10 accounts for %99.99x plus margin of error)
 | 
						|
*/
 | 
						|
#define MAX_FORMAT	(sizeof(FLAGS) + sizeof(LUA_INTFRMLEN) + 10)
 | 
						|
 | 
						|
 | 
						|
static void addquoted (lua_State *L, luaL_Buffer *b, int arg) {
 | 
						|
  size_t l;
 | 
						|
  const char *s = luaL_checklstring(L, arg, &l);
 | 
						|
  luaL_addchar(b, '"');
 | 
						|
  while (l--) {
 | 
						|
    if (*s == '"' || *s == '\\' || *s == '\n') {
 | 
						|
      luaL_addchar(b, '\\');
 | 
						|
      luaL_addchar(b, *s);
 | 
						|
    }
 | 
						|
    else if (*s == '\0' || iscntrl(uchar(*s))) {
 | 
						|
      char buff[10];
 | 
						|
      if (!isdigit(uchar(*(s+1))))
 | 
						|
        snprintf(buff, sizeof(buff), "\\%d", (int)uchar(*s));
 | 
						|
      else
 | 
						|
        snprintf(buff, sizeof(buff), "\\%03d", (int)uchar(*s));
 | 
						|
      luaL_addstring(b, buff);
 | 
						|
    }
 | 
						|
    else
 | 
						|
      luaL_addchar(b, *s);
 | 
						|
    s++;
 | 
						|
  }
 | 
						|
  luaL_addchar(b, '"');
 | 
						|
}
 | 
						|
 | 
						|
static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
 | 
						|
  const char *p = strfrmt;
 | 
						|
  while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++;  /* skip flags */
 | 
						|
  if ((size_t)(p - strfrmt) >= sizeof(FLAGS)/sizeof(char))
 | 
						|
    luaL_error(L, "invalid format (repeated flags)");
 | 
						|
  if (isdigit(uchar(*p))) p++;  /* skip width */
 | 
						|
  if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
 | 
						|
  if (*p == '.') {
 | 
						|
    p++;
 | 
						|
    if (isdigit(uchar(*p))) p++;  /* skip precision */
 | 
						|
    if (isdigit(uchar(*p))) p++;  /* (2 digits at most) */
 | 
						|
  }
 | 
						|
  if (isdigit(uchar(*p)))
 | 
						|
    luaL_error(L, "invalid format (width or precision too long)");
 | 
						|
  *(form++) = '%';
 | 
						|
  memcpy(form, strfrmt, (p - strfrmt + 1) * sizeof(char));
 | 
						|
  form += p - strfrmt + 1;
 | 
						|
  *form = '\0';
 | 
						|
  return p;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
** add length modifier into formats
 | 
						|
*/
 | 
						|
static void addlenmod (char *form, const char *lenmod, size_t size) {
 | 
						|
  size_t l = strlen(form);
 | 
						|
  size_t lm = strlen(lenmod);
 | 
						|
  char spec = form[l - 1];
 | 
						|
  strlcpy(form + l - 1, lenmod, size - (l - 1));
 | 
						|
  form[l + lm - 1] = spec;
 | 
						|
  form[l + lm] = '\0';
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
static int str_format (lua_State *L) {
 | 
						|
  int top = lua_gettop(L);
 | 
						|
  int arg = 1;
 | 
						|
  size_t sfl;
 | 
						|
  const char *strfrmt = luaL_checklstring(L, arg, &sfl);
 | 
						|
  const char *strfrmt_end = strfrmt+sfl;
 | 
						|
  luaL_Buffer b;
 | 
						|
  luaL_buffinit(L, &b);
 | 
						|
  while (strfrmt < strfrmt_end) {
 | 
						|
    if (*strfrmt != L_ESC)
 | 
						|
      luaL_addchar(&b, *strfrmt++);
 | 
						|
    else if (*++strfrmt == L_ESC)
 | 
						|
      luaL_addchar(&b, *strfrmt++);  /* %% */
 | 
						|
    else { /* format item */
 | 
						|
      char form[MAX_FORMAT];  /* to store the format (`%...') */
 | 
						|
      char *buff = luaL_prepbuffsize(&b, MAX_ITEM);  /* to put formatted item */
 | 
						|
      int nb = 0;  /* number of bytes in added item */
 | 
						|
      if (++arg > top)
 | 
						|
        luaL_argerror(L, arg, "no value");
 | 
						|
      strfrmt = scanformat(L, strfrmt, form);
 | 
						|
      switch (*strfrmt++) {
 | 
						|
        case 'c': {
 | 
						|
          nb = str_sprintf(buff, form, luaL_checkint(L, arg));
 | 
						|
          break;
 | 
						|
        }
 | 
						|
        case 'd': case 'i': {
 | 
						|
          lua_Number n = luaL_checknumber(L, arg);
 | 
						|
          LUA_INTFRM_T ni = (LUA_INTFRM_T)n;
 | 
						|
          lua_Number diff = n - (lua_Number)ni;
 | 
						|
          luaL_argcheck(L, -1 < diff && diff < 1, arg,
 | 
						|
                        "not a number in proper range");
 | 
						|
          addlenmod(form, LUA_INTFRMLEN, MAX_FORMAT);
 | 
						|
          nb = str_sprintf(buff, form, ni);
 | 
						|
          break;
 | 
						|
        }
 | 
						|
        case 'o': case 'u': case 'x': case 'X': {
 | 
						|
          lua_Number n = luaL_checknumber(L, arg);
 | 
						|
          unsigned LUA_INTFRM_T ni = (unsigned LUA_INTFRM_T)n;
 | 
						|
          lua_Number diff = n - (lua_Number)ni;
 | 
						|
          luaL_argcheck(L, -1 < diff && diff < 1, arg,
 | 
						|
                        "not a non-negative number in proper range");
 | 
						|
          addlenmod(form, LUA_INTFRMLEN, MAX_FORMAT);
 | 
						|
          nb = str_sprintf(buff, form, ni);
 | 
						|
          break;
 | 
						|
        }
 | 
						|
#if defined(LUA_USE_FLOAT_FORMATS)
 | 
						|
        case 'e': case 'E': case 'f':
 | 
						|
#if defined(LUA_USE_AFORMAT)
 | 
						|
        case 'a': case 'A':
 | 
						|
#endif
 | 
						|
        case 'g': case 'G': {
 | 
						|
          addlenmod(form, LUA_FLTFRMLEN, MAX_FORMAT);
 | 
						|
          nb = str_sprintf(buff, form, (LUA_FLTFRM_T)luaL_checknumber(L, arg));
 | 
						|
          break;
 | 
						|
        }
 | 
						|
#endif
 | 
						|
        case 'q': {
 | 
						|
          addquoted(L, &b, arg);
 | 
						|
          break;
 | 
						|
        }
 | 
						|
        case 's': {
 | 
						|
          size_t l;
 | 
						|
          const char *s = luaL_tolstring(L, arg, &l);
 | 
						|
          if (!strchr(form, '.') && l >= 100) {
 | 
						|
            /* no precision and string is too long to be formatted;
 | 
						|
               keep original string */
 | 
						|
            luaL_addvalue(&b);
 | 
						|
            break;
 | 
						|
          }
 | 
						|
          else {
 | 
						|
            nb = str_sprintf(buff, form, s);
 | 
						|
            lua_pop(L, 1);  /* remove result from 'luaL_tolstring' */
 | 
						|
            break;
 | 
						|
          }
 | 
						|
        }
 | 
						|
        default: {  /* also treat cases `pnLlh' */
 | 
						|
          return luaL_error(L, "invalid option " LUA_QL("%%%c") " to "
 | 
						|
                               LUA_QL("format"), *(strfrmt - 1));
 | 
						|
        }
 | 
						|
      }
 | 
						|
      luaL_addsize(&b, nb);
 | 
						|
    }
 | 
						|
  }
 | 
						|
  luaL_pushresult(&b);
 | 
						|
  return 1;
 | 
						|
}
 | 
						|
 | 
						|
/* }====================================================== */
 | 
						|
 | 
						|
 | 
						|
static const luaL_Reg strlib[] = {
 | 
						|
  {"byte", str_byte},
 | 
						|
  {"char", str_char},
 | 
						|
#if defined(LUA_USE_DUMP)
 | 
						|
  {"dump", str_dump},
 | 
						|
#endif
 | 
						|
  {"find", str_find},
 | 
						|
  {"format", str_format},
 | 
						|
  {"gmatch", str_gmatch},
 | 
						|
  {"gsub", str_gsub},
 | 
						|
  {"len", str_len},
 | 
						|
  {"lower", str_lower},
 | 
						|
  {"match", str_match},
 | 
						|
  {"rep", str_rep},
 | 
						|
  {"reverse", str_reverse},
 | 
						|
  {"sub", str_sub},
 | 
						|
  {"upper", str_upper},
 | 
						|
  {NULL, NULL}
 | 
						|
};
 | 
						|
 | 
						|
 | 
						|
static void createmetatable (lua_State *L) {
 | 
						|
  lua_createtable(L, 0, 1);  /* table to be metatable for strings */
 | 
						|
  lua_pushliteral(L, "");  /* dummy string */
 | 
						|
  lua_pushvalue(L, -2);  /* copy table */
 | 
						|
  lua_setmetatable(L, -2);  /* set table as metatable for strings */
 | 
						|
  lua_pop(L, 1);  /* pop dummy string */
 | 
						|
  lua_pushvalue(L, -2);  /* get string library */
 | 
						|
  lua_setfield(L, -2, "__index");  /* metatable.__index = string */
 | 
						|
  lua_pop(L, 1);  /* pop metatable */
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
** Open string library
 | 
						|
*/
 | 
						|
LUAMOD_API int luaopen_string (lua_State *L) {
 | 
						|
  luaL_newlib(L, strlib);
 | 
						|
  createmetatable(L);
 | 
						|
  return 1;
 | 
						|
}
 | 
						|
 | 
						|
#if defined(_KERNEL)
 | 
						|
 | 
						|
EXPORT_SYMBOL(luaopen_string);
 | 
						|
 | 
						|
#endif
 |