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diff --git a/gnu/lib/libg++/iostream/parsestream.h b/gnu/lib/libg++/iostream/parsestream.h
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+++ b/gnu/lib/libg++/iostream/parsestream.h
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+//    This is part of the iostream library, providing -*- C++ -*- input/output.
+//    Copyright (C) 1991 Per Bothner.
+//
+//    This library is free software; you can redistribute it and/or
+//    modify it under the terms of the GNU Library General Public
+//    License as published by the Free Software Foundation; either
+//    version 2 of the License, or (at your option) any later version.
+//
+//    This library is distributed in the hope that it will be useful,
+//    but WITHOUT ANY WARRANTY; without even the implied warranty of
+//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+//    Library General Public License for more details.
+//
+//    You should have received a copy of the GNU Library General Public
+//    License along with this library; if not, write to the Free
+//    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+#ifndef PARSESTREAM_H
+#define PARSESTREAM_H
+#ifdef __GNUG__
+#pragma interface
+#endif
+#include "streambuf.h"
+
+// A parsebuf is a streambuf optimized for scanning text files.
+// It keeps track of line and column numbers.
+// It is guaranteed to remember the entire current line,
+// as well the '\n'-s on either side of it (if they exist).
+// You can arbitrarily seek (or unget) within this extended line.
+// Other backward seeks are not supported.
+// Normal read semantics are supported (and hence istream operators like >>).
+
+class parsebuf : public backupbuf {
+  protected:
+    _G_fpos_t pos_at_line_start;
+    long _line_length;
+    unsigned long __line_number;
+    char *buf_start;
+    char *buf_end;
+
+  public:
+    parsebuf *chain;
+
+    // Return column number (raw - don't handle tabs etc).
+    // Retult can be -1, meaning: at '\n' before current line.
+    virtual int tell_in_line();
+
+    // seek to (raw) column I in current line.
+    // Result is new (raw) column position - differs from I if unable to seek.
+    // Seek to -1 tries to seek to before previous LF.
+    virtual int seek_in_line(int i);
+
+    // Note: there is no "current line" initially, until something is read.
+
+    // Current line number, starting with 0.
+    // If tell_in_line()==-1, then line number of next line.
+    int line_number() { return __line_number; }
+
+    // Length of current line, not counting either '\n'.
+    int line_length() { return _line_length; }
+    // Current line - not a copy, so file ops may trash it. 
+    virtual char* current_line();
+    virtual streampos seekoff(streamoff, _seek_dir, int mode=ios::in|ios::out);
+    virtual streambuf* setbuf(char* p, int len);
+  protected:
+    parsebuf() : backupbuf() { chain= NULL;
+	__line_number = 0; pos_at_line_start = 0; _line_length = -1; }
+    virtual int pbackfail(int c);
+};
+
+// A string_parsebuf is a parsebuf whose source is a fixed string.
+
+class string_parsebuf : public parsebuf {
+  public:
+    int do_delete;
+    string_parsebuf(char *str, int len, int delete_at_close=0);
+    virtual int underflow();
+    virtual char* current_line();
+    virtual int seek_in_line(int i);
+    virtual int tell_in_line();
+    char *left() const { return base(); }
+    char *right() const { return ebuf(); }
+//    streampos seekoff(streamoff, _seek_dir, int);
+};
+
+// A func_parsebuf calls a given function to get new input.
+// Each call returns an entire NUL-terminated line (without the '\n').
+// That line has been allocated with malloc(), not new.
+// The interface is tailored to the GNU readline library.
+// Example:
+// char* DoReadLine(void* arg)
+// {
+//   char *line = readline((char*)arg); /* 'arg' is used as prompt. */
+//   if line == NULL) { putc('\n', stderr); return NULL; }
+//   if (line[0] != '\0') add_history(line);
+//    return line;
+// }
+// char PromptBuffer[100] = "> ";
+// func_parsebuf my_stream(DoReadLine, PromptBuffer);
+
+typedef char *(*CharReader)(void *arg);
+class istream;
+
+class func_parsebuf : public parsebuf {
+  public:
+    void *arg;
+    CharReader read_func;
+    int backed_up_to_newline;
+    func_parsebuf(CharReader func, void *argm = NULL);
+    int underflow();
+    virtual int tell_in_line();
+    virtual int seek_in_line(int i);
+    virtual char* current_line();
+};
+
+// A general_parsebuf is a parsebuf which gets its input from some
+// other streambuf. It explicitly buffers up an entire line.
+
+class general_parsebuf : public parsebuf {
+  public:
+    streambuf *sbuf;
+    int delete_buf; // Delete sbuf when destroying this.
+    general_parsebuf(streambuf *buf, int delete_arg_buf = 0);
+    int underflow();
+    virtual int tell_in_line();
+    virtual int seek_in_line(int i);
+    ~general_parsebuf();
+    virtual char* current_line();
+};
+
+#if 0
+class parsestream : public istream {
+    streammarker marks[2];
+    short _first; // of the two marks; either 0 or 1
+    int _lineno;
+    int first() { return _first; }
+    int second() { return 1-_first; }
+    int line_length() { marks[second].delta(marks[first]); }
+    int line_length() { marks[second].delta(marks[first]); }
+    int seek_in_line(int i);
+    int tell_in_line();
+    int line_number();
+};
+#endif
+#endif /*!defined(PARSESTREAM_H)*/