add pcre to in tree libs

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@3732 d0543943-73ff-0310-b7d9-9358b9ac24b2

libs/pcre/pcre_scanner.h

@@ -0,0 +1,163 @@
+// 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
+//
+// Regular-expression based scanner for parsing an input stream.
+//
+// Example 1: parse a sequence of "var = number" entries from input:
+//
+//      Scanner scanner(input);
+//      string var;
+//      int number;
+//      scanner.Skip("\\s+");           // Skip any white space we encounter
+//      while (scanner.Consume("(\\w+) = (\\d+)", &var, &number)) {
+//        ...;
+//      }
+
+#ifndef _PCRE_SCANNER_H
+#define _PCRE_SCANNER_H
+
+#include <assert.h>
+#include <string>
+#include <vector>
+#include <pcrecpp.h>
+#include <pcre_stringpiece.h>
+
+namespace pcrecpp {
+
+class Scanner {
+ public:
+  Scanner();
+  explicit Scanner(const std::string& input);
+  ~Scanner();
+
+  // Return current line number.  The returned line-number is
+  // one-based.  I.e. it returns 1 + the number of consumed newlines.
+  //
+  // Note: this method may be slow.  It may take time proportional to
+  // the size of the input.
+  int LineNumber() const;
+
+  // Return the byte-offset that the scanner is looking in the
+  // input data;
+  int Offset() const;
+
+  // Return true iff the start of the remaining input matches "re"
+  bool LookingAt(const RE& re) const;
+
+  // Return true iff all of the following are true
+  //    a. the start of the remaining input matches "re",
+  //    b. if any arguments are supplied, matched sub-patterns can be
+  //       parsed and stored into the arguments.
+  // If it returns true, it skips over the matched input and any
+  // following input that matches the "skip" regular expression.
+  bool Consume(const RE& re,
+               const Arg& arg0 = no_arg,
+               const Arg& arg1 = no_arg,
+               const Arg& arg2 = no_arg
+               // TODO: Allow more arguments?
+               );
+
+  // Set the "skip" regular expression.  If after consuming some data,
+  // a prefix of the input matches this RE, it is automatically
+  // skipped.  For example, a programming language scanner would use
+  // a skip RE that matches white space and comments.
+  //
+  //    scanner.Skip("(\\s|//.*|/[*](.|\n)*?[*]/)*");
+  //
+  // You can pass NULL for "re" if you do not want any data to be skipped.
+  void Skip(const char* re);
+
+  // Temporarily pause "skip"ing. This
+  //   Skip("Foo"); code ; DisableSkip(); code; EnableSkip()
+  // is similar to
+  //   Skip("Foo"); code ; Skip(NULL); code ; Skip("Foo");
+  // but avoids creating/deleting new RE objects.
+  void DisableSkip();
+
+  // Reenable previously paused skipping.  Any prefix of the input
+  // that matches the skip pattern is immediately dropped.
+  void EnableSkip();
+
+  /***** Special wrappers around SetSkip() for some common idioms *****/
+
+  // Arranges to skip whitespace, C comments, C++ comments.
+  // The overall RE is a repeated disjunction of the following REs:
+  //    \\s                     whitespace
+  //    //.*\n                  C++ comment
+  //    /[*](.|\n)*?[*]/        C comment (x*? means minimal repetitions of x)
+  void SkipCXXComments() {
+    Skip("((\\s|//.*\n|/[*](.|\n)*?[*]/)*)");
+  }
+
+  void set_save_comments(bool comments) {
+    save_comments_ = comments;
+  }
+
+  bool save_comments() {
+    return save_comments_;
+  }
+
+  // Append to vector ranges the comments found in the
+  // byte range [start,end] (inclusive) of the input data.
+  // Only comments that were extracted entirely within that
+  // range are returned: no range splitting of atomically-extracted
+  // comments is performed.
+  void GetComments(int start, int end, std::vector<StringPiece> *ranges);
+
+  // Append to vector ranges the comments added
+  // since the last time this was called. This
+  // functionality is provided for efficiency when
+  // interleaving scanning with parsing.
+  void GetNextComments(std::vector<StringPiece> *ranges);
+
+ private:
+  std::string   data_;          // All the input data
+  StringPiece   input_;         // Unprocessed input
+  RE*           skip_;          // If non-NULL, RE for skipping input
+  bool          should_skip_;   // If true, use skip_
+  bool          save_comments_; // If true, aggregate the skip expression
+
+  // the skipped comments
+  // TODO: later consider requiring that the StringPieces be added
+  // in order by their start position
+  std::vector<StringPiece> *comments_;
+
+  // the offset into comments_ that has been returned by GetNextComments
+  int           comments_offset_;
+
+  // helper function to consume *skip_ and honour
+  // save_comments_
+  void ConsumeSkip();
+};
+
+}   // namespace pcrecpp
+
+#endif /* _PCRE_SCANNER_H */