// Find matches in input.
private void allMatches(MachineInput input, int n, DeliverFunc deliver)
{
int end = input.endPos();
if (n < 0)
{
n = end + 1;
}
for (int pos = 0, i = 0, prevMatchEnd = -1; i < n && pos <= end;)
{
int[] matches = doExecute(input, pos, UNANCHORED, prog.numCap);
if (matches == null || matches.Length == 0)
{
break;
}
bool accept = true;
if (matches[1] == pos)
{
// We've found an empty match.
if (matches[0] == prevMatchEnd)
{
// We don't allow an empty match right
// after a previous match, so ignore it.
accept = false;
}
int r = input.step(pos);
if (r < 0)
{
// EOF
pos = end + 1;
}
else
{
pos += r & 0x7;
}
}
else
{
pos = matches[1];
}
prevMatchEnd = matches[1];
if (accept)
{
deliver(pad(matches));
i++;
}
}
}
// match() runs the machine over the input |in| starting at |pos| with the
// RE2 Anchor |anchor|.
// It reports whether a match was found.
// If so, matchcap holds the submatch information.
public bool match(MachineInput @in, int pos, int anchor)
{
int startCond = re2.cond;
if (startCond == Utils.EMPTY_ALL)
{
// impossible
return(false);
}
if ((anchor == RE2.ANCHOR_START || anchor == RE2.ANCHOR_BOTH) && pos != 0)
{
return(false);
}
matched = false;
for (int jj = 0; jj < prog.numCap; ++jj)
{
matchcap[jj] = -1;
}
Queue runq = q0, nextq = q1;
int r = @in.step(pos);
int rune = r >> 3;
int width = r & 7;
int rune1 = -1;
int width1 = 0;
if (r != MachineInput.EOF)
{
r = @in.step(pos + width);
rune1 = r >> 3;
width1 = r & 7;
}
int flag; // bitmask of EMPTY_* flags
if (pos == 0)
{
flag = Utils.emptyOpContext(-1, rune);
}
else
{
flag = @in.context(pos);
}
for (;;)
{
if (runq.isEmpty())
{
if ((startCond & Utils.EMPTY_BEGIN_TEXT) != 0 && pos != 0)
{
// Anchored match, past beginning of text.
break;
}
if (matched)
{
// Have match; finished exploring alternatives.
break;
}
if (re2.prefix.Length != 0 && rune1 != re2.prefixRune && @in.canCheckPrefix())
{
// Match requires literal prefix; fast search for it.
int advance = @in.index(re2, pos);
if (advance < 0)
{
break;
}
pos += advance;
r = @in.step(pos);
rune = r >> 3;
width = r & 7;
r = @in.step(pos + width);
rune1 = r >> 3;
width1 = r & 7;
}
}
if (!matched && (pos == 0 || anchor == RE2.UNANCHORED))
{
// If we are anchoring at begin then only add threads that begin
// at |pos| = 0.
if (ncap > 0)
{
matchcap[0] = pos;
}
add(runq, prog.start, pos, matchcap, flag, null);
}
flag = Utils.emptyOpContext(rune, rune1);
step(runq, nextq, pos, pos + width, rune, flag, anchor, pos == @in.endPos());
if (width == 0)
{
// EOF
break;
}
if (ncap == 0 && matched)
{
// Found a match and not paying attention
// to where it is, so any match will do.
break;
}
pos += width;
rune = rune1;
width = width1;
if (rune != -1)
{
r = @in.step(pos + width);
rune1 = r >> 3;
width1 = r & 7;
}
Queue tmpq = runq;
runq = nextq;
nextq = tmpq;
}
free(nextq);
return(matched);
}
/**
* Returns a copy of {@code src} in which at most {@code maxReplaces} matches for this regexp have
* been replaced by the return value of of function {@code repl} (whose first argument is the
* matched string). No support is provided for expressions (e.g. {@code \1} or {@code $1}) in the
* replacement string.
*/
// This is visible for testing.
public string replaceAllFunc(string src, ReplaceFunc repl, int maxReplaces)
{
int lastMatchEnd = 0; // end position of the most recent match
int searchPos = 0; // position where we next look for a match
StringBuilder buf = new StringBuilder();
MachineInput input = MachineInput.fromUTF16(src);
int numReplaces = 0;
while (searchPos <= src.Length)
{
int[] a = doExecute(input, searchPos, UNANCHORED, 2);
if (a == null || a.Length == 0)
{
break; // no more matches
}
// Copy the unmatched characters before this match.
buf.Append(src.Substring(lastMatchEnd, a[0]));
// Now insert a copy of the replacement string, but not for a
// match of the empty string immediately after another match.
// (Otherwise, we get double replacement for patterns that
// match both empty and nonempty strings.)
// FIXME(adonovan), FIXME(afrozm) - JDK seems to be doing exactly this
// put a replacement for a pattern that also matches empty and non-empty
// strings. The fix would not just be a[1] >= lastMatchEnd, there are a
// few corner cases in that as well, and there are tests which will fail
// when that case is touched (happens only at the end of the input string
// though).
if (a[1] > lastMatchEnd || a[0] == 0)
{
buf.Append(repl(src.Substring(a[0], a[1])));
// Increment the replace count.
++numReplaces;
}
lastMatchEnd = a[1];
// Advance past this match; always advance at least one character.
int width = input.step(searchPos) & 0x7;
if (searchPos + width > a[1])
{
searchPos += width;
}
else if (searchPos + 1 > a[1])
{
// This clause is only needed at the end of the input
// string. In that case, DecodeRuneInString returns width=0.
searchPos++;
}
else
{
searchPos = a[1];
}
if (numReplaces >= maxReplaces)
{
// Should never be greater though.
break;
}
}
// Copy the unmatched characters after the last match.
buf.Append(src.Substring(lastMatchEnd));
return(buf.ToString());
}
