private static CharPtr scanformat(LuaState L, CharPtr strfrmt, CharPtr form)
{
var p = strfrmt;
while (p[0] != '\0' && strchr(FLAGS, p[0]) != null) p = p.next(); /* skip flags */
if ((uint) (p - strfrmt) >= (FLAGS.Length + 1))
LuaLError(L, "invalid format (repeated flags)");
if (isdigit((byte) (p[0]))) p = p.next(); /* skip width */
if (isdigit((byte) (p[0]))) p = p.next(); /* (2 digits at most) */
if (p[0] == '.')
{
p = p.next();
if (isdigit((byte) (p[0]))) p = p.next(); /* skip precision */
if (isdigit((byte) (p[0]))) p = p.next(); /* (2 digits at most) */
}
if (isdigit((byte) (p[0])))
LuaLError(L, "invalid format (width or precision too long)");
form[0] = '%';
form = form.next();
strncpy(form, strfrmt, p - strfrmt + 1);
form += p - strfrmt + 1;
form[0] = '\0';
return p;
}
private static CharPtr match(MatchState ms, CharPtr s, CharPtr p)
{
s = new CharPtr(s);
p = new CharPtr(p);
if (ms.matchdepth-- == 0)
LuaLError(ms.L, "pattern too complex");
init: /* using goto's to optimize tail recursion */
switch (p[0])
{
case '(':
{
/* start capture */
if (p[1] == ')') /* position capture? */
return start_capture(ms, s, p + 2, CAP_POSITION);
return start_capture(ms, s, p + 1, CAP_UNFINISHED);
}
case ')':
{
/* end capture */
return end_capture(ms, s, p + 1);
}
case L_ESC:
{
switch (p[1])
{
case 'b':
{
/* balanced string? */
s = matchbalance(ms, s, p + 2);
if (s == null) return null;
p += 4;
goto init; /* else return match(ms, s, p+4); */
}
case 'f':
{
/* frontier? */
CharPtr ep;
char previous;
p += 2;
if (p[0] != '[')
LuaLError(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((byte) (previous), p, ep - 1) != 0) ||
(matchbracketclass((byte) (s[0]), p, ep - 1) == 0)) return null;
p = ep;
goto init; /* else return match(ms, s, ep); */
}
default:
{
if (isdigit(p[1]))
{
/* capture results (%0-%9)? */
s = match_capture(ms, s, (byte) (p[1]));
if (s == null) return null;
p += 2;
goto init; /* else return match(ms, s, p+2) */
}
//ismeretlen hiba miatt lett ide átmásolva
{
/* it is a pattern item */
var ep = classend(ms, p); /* points to what is next */
var m = (s < ms.src_end) && (singlematch((byte) (s[0]), p, ep) != 0) ? 1 : 0;
switch (ep[0])
{
case '?':
{
/* optional */
CharPtr res;
if ((m != 0) && ((res = match(ms, s + 1, ep + 1)) != null))
return res;
p = ep + 1;
goto init; /* else return match(ms, s, ep+1); */
}
case '*':
{
/* 0 or more repetitions */
return max_expand(ms, s, p, ep);
}
case '+':
{
/* 1 or more repetitions */
return ((m != 0) ? max_expand(ms, s + 1, p, ep) : null);
}
case '-':
{
/* 0 or more repetitions (minimum) */
return min_expand(ms, s, p, ep);
}
default:
{
if (m == 0) return null;
s = s.next();
p = ep;
goto init; /* else return match(ms, s+1, ep); */
}
}
}
//goto dflt; /* case default */
}
}
}
case '\0':
{
/* end of pattern */
return s; /* match succeeded */
}
case '$':
{
if (p[1] == '\0') /* is the `$' the last char in pattern? */
return (s == ms.src_end) ? s : null; /* check end of string */
goto dflt;
}
default:
dflt:
{
/* it is a pattern item */
var ep = classend(ms, p); /* points to what is next */
var m = (s < ms.src_end) && (singlematch((byte) (s[0]), p, ep) != 0) ? 1 : 0;
switch (ep[0])
{
case '?':
{
/* optional */
CharPtr res;
if ((m != 0) && ((res = match(ms, s + 1, ep + 1)) != null))
return res;
p = ep + 1;
goto init; /* else return match(ms, s, ep+1); */
}
case '*':
{
/* 0 or more repetitions */
return max_expand(ms, s, p, ep);
}
case '+':
{
/* 1 or more repetitions */
return ((m != 0) ? max_expand(ms, s + 1, p, ep) : null);
}
case '-':
{
/* 0 or more repetitions (minimum) */
return min_expand(ms, s, p, ep);
}
default:
{
if (m == 0) return null;
s = s.next();
p = ep;
goto init; /* else return match(ms, s+1, ep); */
}
}
}
}
}
private static CharPtr min_expand(MatchState ms, CharPtr s,
CharPtr p, CharPtr ep)
{
for (;;)
{
var res = match(ms, s, ep + 1);
if (res != null)
return res;
if ((s < ms.src_end) && (singlematch((byte) (s[0]), p, ep) != 0))
s = s.next(); /* try with one more repetition */
else return null;
}
}
private static CharPtr matchbalance(MatchState ms, CharPtr s,
CharPtr p)
{
if ((p[0] == 0) || (p[1] == 0))
LuaLError(ms.L, "unbalanced pattern");
if (s[0] != p[0]) return null;
int b = p[0];
int e = p[1];
var cont = 1;
while ((s = s.next()) < ms.src_end)
{
if (s[0] == e)
{
if (--cont == 0) return s + 1;
}
else if (s[0] == b) cont++;
}
return null; /* string ends out of balance */
}
private static int matchbracketclass(int c, CharPtr p, CharPtr ec)
{
var sig = 1;
if (p[1] == '^')
{
sig = 0;
p = p.next(); /* skip the `^' */
}
while ((p = p.next()) < ec)
{
if (p == L_ESC)
{
p = p.next();
if (match_class((char) c, p[0]) != 0)
return sig;
}
else if ((p[1] == '-') && (p + 2 < ec))
{
p += 2;
if ((byte) ((p[-2])) <= c && (c <= (byte) p[0]))
return sig;
}
else if ((byte) (p[0]) == c) return sig;
}
return (sig == 0) ? 1 : 0;
}
private static CharPtr classend(MatchState ms, CharPtr p)
{
p = new CharPtr(p);
var c = p[0];
p = p.next();
switch (c)
{
case L_ESC:
{
if (p[0] == '\0')
LuaLError(ms.L, "malformed pattern (ends with " + LUA_QL("%") + ")");
return p + 1;
}
case '[':
{
if (p[0] == '^') p = p.next();
do
{
/* look for a `]' */
if (p[0] == '\0')
LuaLError(ms.L, "malformed pattern (missing " + LUA_QL("]") + ")");
c = p[0];
p = p.next();
if (c == L_ESC && p[0] != '\0')
p = p.next(); /* skip escapes (e.g. `%]') */
} while (p[0] != ']');
return p + 1;
}
default:
{
return p;
}
}
}