--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libcpp/directives-only.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,241 @@
+/* CPP Library - directive only preprocessing for distributed compilation.
+   Copyright (C) 2007, 2009
+   Free Software Foundation, Inc.
+   Contributed by Ollie Wild <aaw@google.com>.
+
+This program is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 3, or (at your option) any
+later version.
+
+This program 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include "system.h"
+#include "cpplib.h"
+#include "internal.h"
+
+/* DO (Directive only) flags. */
+#define DO_BOL		 (1 << 0) /* At the beginning of a logical line. */
+#define DO_STRING	 (1 << 1) /* In a string constant. */
+#define DO_CHAR		 (1 << 2) /* In a character constant. */
+#define DO_BLOCK_COMMENT (1 << 3) /* In a block comment. */
+#define DO_LINE_COMMENT	 (1 << 4) /* In a single line "//-style" comment. */
+
+#define DO_LINE_SPECIAL (DO_STRING | DO_CHAR | DO_LINE_COMMENT)
+#define DO_SPECIAL	(DO_LINE_SPECIAL | DO_BLOCK_COMMENT)
+
+/* Writes out the preprocessed file, handling spacing and paste
+   avoidance issues.  */
+void
+_cpp_preprocess_dir_only (cpp_reader *pfile,
+			  const struct _cpp_dir_only_callbacks *cb)
+{
+  struct cpp_buffer *buffer;
+  const unsigned char *cur, *base, *next_line, *rlimit;
+  cppchar_t c, last_c;
+  unsigned flags;
+  linenum_type lines;
+  int col;
+  source_location loc;
+
+ restart:
+  /* Buffer initialization ala _cpp_clean_line(). */
+  buffer = pfile->buffer;
+  buffer->cur_note = buffer->notes_used = 0;
+  buffer->cur = buffer->line_base = buffer->next_line;
+  buffer->need_line = false;
+
+  /* This isn't really needed.  It prevents a compiler warning, though. */
+  loc = pfile->line_table->highest_line;
+
+  /* Scan initialization. */
+  next_line = cur = base = buffer->cur;
+  rlimit = buffer->rlimit;
+  flags = DO_BOL;
+  lines = 0;
+  col = 1;
+
+  for (last_c = '\n', c = *cur; cur < rlimit; last_c = c, c = *++cur, ++col)
+    {
+      /* Skip over escaped newlines. */
+      if (__builtin_expect (c == '\\', false))
+	{
+	  const unsigned char *tmp = cur + 1;
+
+	  while (is_nvspace (*tmp) && tmp < rlimit)
+	    tmp++;
+	  if (*tmp == '\r')
+	    tmp++;
+	  if (*tmp == '\n' && tmp < rlimit)
+	    {
+	      CPP_INCREMENT_LINE (pfile, 0);
+	      lines++;
+	      col = 0;
+	      cur = tmp;
+	      c = last_c;
+	      continue;
+	    }
+	}
+
+      if (__builtin_expect (last_c == '#', false) && !(flags & DO_SPECIAL))
+	{
+	  if (c != '#' && (flags & DO_BOL))
+	  {
+	    struct line_maps *line_table;
+
+	    if (!pfile->state.skipping && next_line != base)
+	      cb->print_lines (lines, base, next_line - base);
+
+	    /* Prep things for directive handling. */
+	    buffer->next_line = cur;
+	    buffer->need_line = true;
+	    _cpp_get_fresh_line (pfile);
+
+	    /* Ensure proper column numbering for generated error messages. */
+	    buffer->line_base -= col - 1;
+
+	    _cpp_handle_directive (pfile, 0 /* ignore indented */);
+
+	    /* Sanitize the line settings.  Duplicate #include's can mess
+	       things up. */
+	    line_table = pfile->line_table;
+	    line_table->highest_location = line_table->highest_line;
+
+	    /* The if block prevents us from outputing line information when
+	       the file ends with a directive and no newline.  Note that we
+	       must use pfile->buffer, not buffer. */
+	    if (pfile->buffer->next_line < pfile->buffer->rlimit)
+	      cb->maybe_print_line (pfile->line_table->highest_line);
+
+	    goto restart;
+	  }
+
+	  flags &= ~DO_BOL;
+	  pfile->mi_valid = false;
+	}
+      else if (__builtin_expect (last_c == '/', false) \
+	       && !(flags & DO_SPECIAL) && c != '*' && c != '/')
+	{
+	  /* If a previous slash is not starting a block comment, clear the
+	     DO_BOL flag.  */
+	  flags &= ~DO_BOL;
+	  pfile->mi_valid = false;
+	}
+
+      switch (c)
+	{
+	case '/':
+	  if ((flags & DO_BLOCK_COMMENT) && last_c == '*')
+	    {
+	      flags &= ~DO_BLOCK_COMMENT;
+	      c = 0;
+	    }
+	  else if (!(flags & DO_SPECIAL) && last_c == '/')
+	    flags |= DO_LINE_COMMENT;
+	  else if (!(flags & DO_SPECIAL))
+	    /* Mark the position for possible error reporting. */
+	    LINEMAP_POSITION_FOR_COLUMN (loc, pfile->line_table, col);
+
+	  break;
+
+	case '*':
+	  if (!(flags & DO_SPECIAL))
+	    {
+	      if (last_c == '/')
+		flags |= DO_BLOCK_COMMENT;
+	      else
+		{
+		  flags &= ~DO_BOL;
+		  pfile->mi_valid = false;
+		}
+	    }
+
+	  break;
+
+	case '\'':
+	case '"':
+	  {
+	    unsigned state = (c == '"') ? DO_STRING : DO_CHAR;
+
+	    if (!(flags & DO_SPECIAL))
+	      {
+		flags |= state;
+		flags &= ~DO_BOL;
+		pfile->mi_valid = false;
+	      }
+	    else if ((flags & state) && last_c != '\\')
+	      flags &= ~state;
+
+	    break;
+	  }
+
+	case '\\':
+	  {
+	    if ((flags & (DO_STRING | DO_CHAR)) && last_c == '\\')
+	      c = 0;
+
+	    if (!(flags & DO_SPECIAL))
+	      {
+		flags &= ~DO_BOL;
+		pfile->mi_valid = false;
+	      }
+
+	    break;
+	  }
+
+	case '\n':
+	  CPP_INCREMENT_LINE (pfile, 0);
+	  lines++;
+	  col = 0;
+	  flags &= ~DO_LINE_SPECIAL;
+	  if (!(flags & DO_SPECIAL))
+	    flags |= DO_BOL;
+	  break;
+
+	case '#':
+	  next_line = cur;
+	  /* Don't update DO_BOL yet. */
+	  break;
+
+	case ' ': case '\t': case '\f': case '\v': case '\0':
+	  break;
+
+	default:
+	  if (!(flags & DO_SPECIAL))
+	    {
+	      flags &= ~DO_BOL;
+	      pfile->mi_valid = false;
+	    }
+	  break;
+	}
+    }
+
+  if (flags & DO_BLOCK_COMMENT)
+    cpp_error_with_line (pfile, CPP_DL_ERROR, loc, 0, "unterminated comment");
+
+  if (!pfile->state.skipping && cur != base)
+    {
+      /* If the file was not newline terminated, add rlimit, which is
+         guaranteed to point to a newline, to the end of our range.  */
+      if (cur[-1] != '\n')
+	{
+	  cur++;
+	  CPP_INCREMENT_LINE (pfile, 0);
+	  lines++;
+	}
+
+      cb->print_lines (lines, base, cur - base);
+    }
+
+  _cpp_pop_buffer (pfile);
+  if (pfile->buffer)
+    goto restart;
+}