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+// Copyright (c) 2005, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Author: Sanjay Ghemawat
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <vector>
+#include <assert.h>
+
+#include "pcrecpp_internal.h"
+#include "pcre_scanner.h"
+
+using std::vector;
+
+namespace pcrecpp {
+
+Scanner::Scanner()
+ : data_(),
+ input_(data_),
+ skip_(NULL),
+ should_skip_(false),
+ skip_repeat_(false),
+ save_comments_(false),
+ comments_(NULL),
+ comments_offset_(0) {
+}
+
+Scanner::Scanner(const string& in)
+ : data_(in),
+ input_(data_),
+ skip_(NULL),
+ should_skip_(false),
+ skip_repeat_(false),
+ save_comments_(false),
+ comments_(NULL),
+ comments_offset_(0) {
+}
+
+Scanner::~Scanner() {
+ delete skip_;
+ delete comments_;
+}
+
+void Scanner::SetSkipExpression(const char* re) {
+ delete skip_;
+ if (re != NULL) {
+ skip_ = new RE(re);
+ should_skip_ = true;
+ skip_repeat_ = true;
+ ConsumeSkip();
+ } else {
+ skip_ = NULL;
+ should_skip_ = false;
+ skip_repeat_ = false;
+ }
+}
+
+void Scanner::Skip(const char* re) {
+ delete skip_;
+ if (re != NULL) {
+ skip_ = new RE(re);
+ should_skip_ = true;
+ skip_repeat_ = false;
+ ConsumeSkip();
+ } else {
+ skip_ = NULL;
+ should_skip_ = false;
+ skip_repeat_ = false;
+ }
+}
+
+void Scanner::DisableSkip() {
+ assert(skip_ != NULL);
+ should_skip_ = false;
+}
+
+void Scanner::EnableSkip() {
+ assert(skip_ != NULL);
+ should_skip_ = true;
+ ConsumeSkip();
+}
+
+int Scanner::LineNumber() const {
+ // TODO: Make it more efficient by keeping track of the last point
+ // where we computed line numbers and counting newlines since then.
+ // We could use std:count, but not all systems have it. :-(
+ int count = 1;
+ for (const char* p = data_.data(); p < input_.data(); ++p)
+ if (*p == '\n')
+ ++count;
+ return count;
+}
+
+int Scanner::Offset() const {
+ return (int)(input_.data() - data_.c_str());
+}
+
+bool Scanner::LookingAt(const RE& re) const {
+ int consumed;
+ return re.DoMatch(input_, RE::ANCHOR_START, &consumed, 0, 0);
+}
+
+
+bool Scanner::Consume(const RE& re,
+ const Arg& arg0,
+ const Arg& arg1,
+ const Arg& arg2) {
+ const bool result = re.Consume(&input_, arg0, arg1, arg2);
+ if (result && should_skip_) ConsumeSkip();
+ return result;
+}
+
+// helper function to consume *skip_ and honour save_comments_
+void Scanner::ConsumeSkip() {
+ const char* start_data = input_.data();
+ while (skip_->Consume(&input_)) {
+ if (!skip_repeat_) {
+ // Only one skip allowed.
+ break;
+ }
+ }
+ if (save_comments_) {
+ if (comments_ == NULL) {
+ comments_ = new vector<StringPiece>;
+ }
+ // already pointing one past end, so no need to +1
+ int length = (int)(input_.data() - start_data);
+ if (length > 0) {
+ comments_->push_back(StringPiece(start_data, length));
+ }
+ }
+}
+
+
+void Scanner::GetComments(int start, int end, vector<StringPiece> *ranges) {
+ // short circuit out if we've not yet initialized comments_
+ // (e.g., when save_comments is false)
+ if (!comments_) {
+ return;
+ }
+ // TODO: if we guarantee that comments_ will contain StringPieces
+ // that are ordered by their start, then we can do a binary search
+ // for the first StringPiece at or past start and then scan for the
+ // ones contained in the range, quit early (use equal_range or
+ // lower_bound)
+ for (vector<StringPiece>::const_iterator it = comments_->begin();
+ it != comments_->end(); ++it) {
+ if ((it->data() >= data_.c_str() + start &&
+ it->data() + it->size() <= data_.c_str() + end)) {
+ ranges->push_back(*it);
+ }
+ }
+}
+
+
+void Scanner::GetNextComments(vector<StringPiece> *ranges) {
+ // short circuit out if we've not yet initialized comments_
+ // (e.g., when save_comments is false)
+ if (!comments_) {
+ return;
+ }
+ for (vector<StringPiece>::const_iterator it =
+ comments_->begin() + comments_offset_;
+ it != comments_->end(); ++it) {
+ ranges->push_back(*it);
+ ++comments_offset_;
+ }
+}
+
+} // namespace pcrecpp