initial commit

1 files changed, 1348 insertions, 0 deletions

diff --git a/gcc/cppfiles.c b/gcc/cppfiles.c
new file mode 100755
index 0000000..7e1c0bb
--- /dev/null
+++ b/gcc/cppfiles.c
@@ -0,0 +1,1348 @@
+/* Part of CPP library.  (include file handling)
+   Copyright (C) 1986, 87, 89, 92 - 95, 98, 1999 Free Software Foundation, Inc.
+   Written by Per Bothner, 1994.
+   Based on CCCP program by Paul Rubin, June 1986
+   Adapted to ANSI C, Richard Stallman, Jan 1987
+   Split out of cpplib.c, Zack Weinberg, Oct 1998
+
+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 2, 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; if not, write to the Free Software
+Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+ In other words, you are welcome to use, share and improve this program.
+ You are forbidden to forbid anyone else to use, share and improve
+ what you give them.   Help stamp out software-hoarding!  */
+
+#include "config.h"
+#include "system.h"
+#include "cpplib.h"
+
+/* The entry points to this file are: find_include_file, finclude,
+   include_hash, append_include_chain, deps_output, and file_cleanup.
+   file_cleanup is only called through CPP_BUFFER(pfile)->cleanup,
+   so it's static anyway. */
+
+/* CYGNUS LOCAL - obscured headers */
+static int open_include_file_name PARAMS ((cpp_reader*, char *));
+/* END CYGNUS LOCAL - obscured headers */
+static struct include_hash *redundant_include_p
+					PROTO ((cpp_reader *,
+						struct include_hash *,
+						struct file_name_list *));
+static struct file_name_map *read_name_map	PROTO ((cpp_reader *,
+							const char *));
+static char *read_filename_string	PROTO ((int, FILE *));
+static char *remap_filename 		PROTO ((cpp_reader *, char *,
+						struct file_name_list *));
+static long safe_read			PROTO ((int, char *, int));
+static void simplify_pathname		PROTO ((char *));
+static struct file_name_list *actual_directory PROTO ((cpp_reader *, char *));
+
+#if 0
+static void hack_vms_include_specification PROTO ((char *));
+#endif
+
+/* Windows does not natively support inodes, and neither does MSDOS.
+   VMS has non-numeric inodes. */
+#ifdef VMS
+#define INO_T_EQ(a, b) (!bcmp((char *) &(a), (char *) &(b), sizeof (a)))
+#elif (defined _WIN32 && !defined CYGWIN) || defined __MSDOS__
+#define INO_T_EQ(a, b) 0
+#else
+#define INO_T_EQ(a, b) ((a) == (b))
+#endif
+
+/* Append an entry for dir DIR to list LIST, simplifying it if
+   possible.  SYS says whether this is a system include directory.
+   *** DIR is modified in place.  It must be writable and permanently
+   allocated. LIST is a pointer to the head pointer, because we actually
+   *prepend* the dir, and reverse the list later (in merge_include_chains). */
+void
+append_include_chain (pfile, list, dir, sysp)
+     cpp_reader *pfile;
+     struct file_name_list **list;
+     const char *dir;
+     int sysp;
+{
+  struct file_name_list *new;
+  struct stat st;
+  unsigned int len;
+  char * newdir = xstrdup (dir);
+
+  simplify_pathname (newdir);
+  if (stat (newdir, &st))
+    {
+      /* Dirs that don't exist are silently ignored. */
+      if (errno != ENOENT)
+	cpp_perror_with_name (pfile, newdir);
+      return;
+    }
+
+  if (!S_ISDIR (st.st_mode))
+    {
+      cpp_message (pfile, 1, "%s: %s: Not a directory", progname, newdir);
+      return;
+    }
+
+  len = strlen(newdir);
+  if (len > pfile->max_include_len)
+    pfile->max_include_len = len;
+  
+  new = (struct file_name_list *)xmalloc (sizeof (struct file_name_list));
+  new->name = newdir;
+  new->nlen = len;
+  new->next = *list;
+  new->ino  = st.st_ino;
+  new->dev  = st.st_dev;
+  new->sysp = sysp;
+  new->name_map = NULL;
+
+  *list = new;
+}
+
+/* Merge the four include chains together in the order quote, bracket,
+   system, after.  Remove duplicate dirs (as determined by
+   INO_T_EQ()).  The system_include and after_include chains are never
+   referred to again after this function; all access is through the
+   bracket_include path.
+
+   For the future: Check if the directory is empty (but
+   how?) and possibly preload the include hash. */
+
+void
+merge_include_chains (opts)
+     struct cpp_options *opts;
+{
+  struct file_name_list *prev, *next, *cur, *other;
+  struct file_name_list *quote, *brack, *systm, *after;
+  struct file_name_list *qtail, *btail, *stail, *atail;
+
+  qtail = opts->quote_include;
+  btail = opts->bracket_include;
+  stail = opts->system_include;
+  atail = opts->after_include;
+
+  /* Nreverse the four lists. */
+  prev = 0;
+  for (cur = qtail; cur; cur = next)
+    {
+      next = cur->next;
+      cur->next = prev;
+      prev = cur;
+    }
+  quote = prev;
+
+  prev = 0;
+  for (cur = btail; cur; cur = next)
+    {
+      next = cur->next;
+      cur->next = prev;
+      prev = cur;
+    }
+  brack = prev;
+
+  prev = 0;
+  for (cur = stail; cur; cur = next)
+    {
+      next = cur->next;
+      cur->next = prev;
+      prev = cur;
+    }
+  systm = prev;
+
+  prev = 0;
+  for (cur = atail; cur; cur = next)
+    {
+      next = cur->next;
+      cur->next = prev;
+      prev = cur;
+    }
+  after = prev;
+
+  /* Paste together bracket, system, and after include chains. */
+  if (stail)
+    stail->next = after;
+  else
+    systm = after;
+  if (btail)
+    btail->next = systm;
+  else
+    brack = systm;
+
+  /* This is a bit tricky.
+     First we drop dupes from the quote-include list.
+     Then we drop dupes from the bracket-include list.
+     Finally, if qtail and brack are the same directory,
+     we cut out qtail.
+
+     We can't just merge the lists and then uniquify them because
+     then we may lose directories from the <> search path that should
+     be there; consider -Ifoo -Ibar -I- -Ifoo -Iquux. It is however
+     safe to treat -Ibar -Ifoo -I- -Ifoo -Iquux as if written
+     -Ibar -I- -Ifoo -Iquux. */
+
+  for (cur = quote; cur; cur = cur->next)
+    {
+      for (other = quote; other != cur; other = other->next)
+        if (INO_T_EQ (cur->ino, other->ino)
+	    && cur->dev == other->dev)
+          {
+	    prev->next = cur->next;
+	    free (cur->name);
+	    free (cur);
+	    cur = prev;
+	    break;
+	  }
+      prev = cur;
+    }
+  qtail = prev;
+
+  for (cur = brack; cur; cur = cur->next)
+    {
+      for (other = brack; other != cur; other = other->next)
+        if (INO_T_EQ (cur->ino, other->ino)
+	    && cur->dev == other->dev)
+          {
+	    prev->next = cur->next;
+	    free (cur->name);
+	    free (cur);
+	    cur = prev;
+	    break;
+	  }
+      prev = cur;
+    }
+
+  if (quote)
+    {
+      if (INO_T_EQ (qtail->ino, brack->ino) && qtail->dev == brack->dev)
+        {
+	  if (quote == qtail)
+	    {
+	      free (quote->name);
+	      free (quote);
+	      quote = brack;
+	    }
+	  else
+	    {
+	      cur = quote;
+	      while (cur->next != qtail)
+		  cur = cur->next;
+	      cur->next = brack;
+	      free (qtail->name);
+	      free (qtail);
+	    }
+	}
+      else
+	  qtail->next = brack;
+    }
+  else
+      quote = brack;
+
+  opts->quote_include = quote;
+  opts->bracket_include = brack;
+  opts->system_include = NULL;
+  opts->after_include = NULL;
+}
+
+/* Look up or add an entry to the table of all includes.  This table
+ is indexed by the name as it appears in the #include line.  The
+ ->next_this_file chain stores all different files with the same
+ #include name (there are at least three ways this can happen).  The
+ hash function could probably be improved a bit. */
+
+struct include_hash *
+include_hash (pfile, fname, add)
+     cpp_reader *pfile;
+     char *fname;
+     int add;
+{
+  unsigned int hash = 0;
+  struct include_hash *l, *m;
+  char *f = fname;
+
+  while (*f)
+    hash += *f++;
+
+  l = pfile->all_include_files[hash % ALL_INCLUDE_HASHSIZE];
+  m = 0;
+  for (; l; m = l, l = l->next)
+    if (!strcmp (l->nshort, fname))
+      return l;
+
+  if (!add)
+    return 0;
+  
+  l = (struct include_hash *) xmalloc (sizeof (struct include_hash));
+  l->next = NULL;
+  l->next_this_file = NULL;
+  l->foundhere = NULL;
+  l->buf = NULL;
+  l->limit = NULL;
+  if (m)
+    m->next = l;
+  else
+    pfile->all_include_files[hash % ALL_INCLUDE_HASHSIZE] = l;
+  
+  return l;
+}
+
+/* Return 0 if the file pointed to by IHASH has never been included before,
+         -1 if it has been included before and need not be again,
+	 or a pointer to an IHASH entry which is the file to be reread.
+   "Never before" is with respect to the position in ILIST.
+
+   This will not detect redundancies involving odd uses of the
+   `current directory' rule for "" includes.  They aren't quite
+   pathological, but I think they are rare enough not to worry about.
+   The simplest example is:
+
+   top.c:
+   #include "a/a.h"
+   #include "b/b.h"
+
+   a/a.h:
+   #include "../b/b.h"
+
+   and the problem is that for `current directory' includes,
+   ihash->foundhere is not on any of the global include chains,
+   so the test below (i->foundhere == l) may be false even when
+   the directories are in fact the same.  */
+
+static struct include_hash *
+redundant_include_p (pfile, ihash, ilist)
+     cpp_reader *pfile;
+     struct include_hash *ihash;
+     struct file_name_list *ilist;
+{
+  struct file_name_list *l;
+  struct include_hash *i;
+
+  if (! ihash->foundhere)
+    return 0;
+
+  for (i = ihash; i; i = i->next_this_file)
+    for (l = ilist; l; l = l->next)
+       if (i->foundhere == l)
+	 /* The control_macro works like this: If it's NULL, the file
+	    is to be included again.  If it's "", the file is never to
+	    be included again.  If it's a string, the file is not to be
+	    included again if the string is the name of a defined macro. */
+	 return (i->control_macro
+		 && (i->control_macro[0] == '\0'
+		     || cpp_lookup (pfile, i->control_macro, -1, -1)))
+	     ? (struct include_hash *)-1 : i;
+
+  return 0;
+}
+
+static int
+file_cleanup (pbuf, pfile)
+     cpp_buffer *pbuf;
+     cpp_reader *pfile;
+{
+  if (pbuf->buf)
+    {
+      free (pbuf->buf);
+      pbuf->buf = 0;
+    }
+  if (pfile->system_include_depth)
+    pfile->system_include_depth--;
+  return 0;
+}
+
+/* Search for include file FNAME in the include chain starting at
+   SEARCH_START.  Return -2 if this file doesn't need to be included
+   (because it was included already and it's marked idempotent),
+   -1 if an error occurred, or a file descriptor open on the file.
+   *IHASH is set to point to the include hash entry for this file, and
+   *BEFORE is 1 if the file was included before (but needs to be read
+   again). */
+int
+find_include_file (pfile, fname, search_start, ihash, before)
+     cpp_reader *pfile;
+     char *fname;
+     struct file_name_list *search_start;
+     struct include_hash **ihash;
+     int *before;
+{
+  struct file_name_list *l;
+  struct include_hash *ih, *jh;
+  int f, len;
+  char *name;
+  
+  ih = include_hash (pfile, fname, 1);
+  jh = redundant_include_p (pfile, ih,
+			    fname[0] == '/' ? ABSOLUTE_PATH : search_start);
+
+  if (jh != 0)
+    {
+      *before = 1;
+      *ihash = jh;
+
+      if (jh == (struct include_hash *)-1)
+	return -2;
+      else
+	{
+	  /* CYGNUS LOCAL - obscured headers */
+	  return open_include_file_name (pfile, jh->name);
+	  /* END CYGNUS LOCAL - obscured headers */
+	}
+    }
+
+  if (ih->foundhere)
+    /* A file is already known by this name, but it's not the same file.
+       Allocate another include_hash block and add it to the next_this_file
+       chain. */
+    {
+      jh = (struct include_hash *)xmalloc (sizeof (struct include_hash));
+      while (ih->next_this_file) ih = ih->next_this_file;
+
+      ih->next_this_file = jh;
+      jh = ih;
+      ih = ih->next_this_file;
+
+      ih->next = NULL;
+      ih->next_this_file = NULL;
+      ih->buf = NULL;
+      ih->limit = NULL;
+    }
+  *before = 0;
+  *ihash = ih;
+  ih->nshort = xstrdup (fname);
+  ih->control_macro = NULL;
+  
+  /* If the pathname is absolute, just open it. */ 
+  if (fname[0] == '/')
+    {
+      ih->foundhere = ABSOLUTE_PATH;
+      ih->name = ih->nshort;
+      /* CYGNUS LOCAL - obscured headers */
+      return open_include_file_name (pfile, ih->name);
+      /* END CYGNUS LOCAL - obscured headers */
+    }
+
+  /* Search directory path, trying to open the file. */
+
+  len = strlen (fname);
+  name = xmalloc (len + pfile->max_include_len + 2 + INCLUDE_LEN_FUDGE);
+
+  for (l = search_start; l; l = l->next)
+    {
+      bcopy (l->name, name, l->nlen);
+      name[l->nlen] = '/';
+      strcpy (&name[l->nlen+1], fname);
+      simplify_pathname (name);
+      if (CPP_OPTIONS (pfile)->remap)
+	name = remap_filename (pfile, name, l);
+      
+      /* CYGNUS LOCAL - obscured headers */
+      f = open_include_file_name (pfile, name);
+      /* END CYGNUS LOCAL - obscured headers */
+#ifdef EACCES
+      if (f == -1 && errno == EACCES)
+	{
+	  cpp_error(pfile, "included file `%s' exists but is not readable",
+		    name);
+	  return -1;
+	}
+#endif
+
+      if (f >= 0)
+        {
+	  ih->foundhere = l;
+	  ih->name = xrealloc (name, strlen (name)+1);
+	  return f;
+        }
+    }
+  
+    if (jh)
+      {
+	jh->next_this_file = NULL;
+	free (ih);
+      }
+    free (name);
+    *ihash = (struct include_hash *)-1;
+    return -1;
+}
+
+/* The file_name_map structure holds a mapping of file names for a
+   particular directory.  This mapping is read from the file named
+   FILE_NAME_MAP_FILE in that directory.  Such a file can be used to
+   map filenames on a file system with severe filename restrictions,
+   such as DOS.  The format of the file name map file is just a series
+   of lines with two tokens on each line.  The first token is the name
+   to map, and the second token is the actual name to use.  */
+
+struct file_name_map
+{
+  struct file_name_map *map_next;
+  char *map_from;
+  char *map_to;
+};
+
+#define FILE_NAME_MAP_FILE "header.gcc"
+
+/* Read a space delimited string of unlimited length from a stdio
+   file.  */
+
+static char *
+read_filename_string (ch, f)
+     int ch;
+     FILE *f;
+{
+  char *alloc, *set;
+  int len;
+
+  len = 20;
+  set = alloc = xmalloc (len + 1);
+  if (! is_space[ch])
+    {
+      *set++ = ch;
+      while ((ch = getc (f)) != EOF && ! is_space[ch])
+	{
+	  if (set - alloc == len)
+	    {
+	      len *= 2;
+	      alloc = xrealloc (alloc, len + 1);
+	      set = alloc + len / 2;
+	    }
+	  *set++ = ch;
+	}
+    }
+  *set = '\0';
+  ungetc (ch, f);
+  return alloc;
+}
+
+/* This structure holds a linked list of file name maps, one per directory.  */
+
+struct file_name_map_list
+{
+  struct file_name_map_list *map_list_next;
+  char *map_list_name;
+  struct file_name_map *map_list_map;
+};
+
+/* Read the file name map file for DIRNAME.  */
+
+static struct file_name_map *
+read_name_map (pfile, dirname)
+     cpp_reader *pfile;
+     const char *dirname;
+{
+  register struct file_name_map_list *map_list_ptr;
+  char *name;
+  FILE *f;
+
+  for (map_list_ptr = CPP_OPTIONS (pfile)->map_list; map_list_ptr;
+       map_list_ptr = map_list_ptr->map_list_next)
+    if (! strcmp (map_list_ptr->map_list_name, dirname))
+      return map_list_ptr->map_list_map;
+
+  map_list_ptr = ((struct file_name_map_list *)
+		  xmalloc (sizeof (struct file_name_map_list)));
+  map_list_ptr->map_list_name = xstrdup (dirname);
+
+  name = (char *) alloca (strlen (dirname) + strlen (FILE_NAME_MAP_FILE) + 2);
+  strcpy (name, dirname);
+  if (*dirname)
+    strcat (name, "/");
+  strcat (name, FILE_NAME_MAP_FILE);
+  f = fopen (name, "r");
+  if (!f)
+    map_list_ptr->map_list_map = (struct file_name_map *)-1;
+  else
+    {
+      int ch;
+      int dirlen = strlen (dirname);
+
+      while ((ch = getc (f)) != EOF)
+	{
+	  char *from, *to;
+	  struct file_name_map *ptr;
+
+	  if (is_space[ch])
+	    continue;
+	  from = read_filename_string (ch, f);
+	  while ((ch = getc (f)) != EOF && is_hor_space[ch])
+	    ;
+	  to = read_filename_string (ch, f);
+
+	  ptr = ((struct file_name_map *)
+		 xmalloc (sizeof (struct file_name_map)));
+	  ptr->map_from = from;
+
+	  /* Make the real filename absolute.  */
+	  if (*to == '/')
+	    ptr->map_to = to;
+	  else
+	    {
+	      ptr->map_to = xmalloc (dirlen + strlen (to) + 2);
+	      strcpy (ptr->map_to, dirname);
+	      ptr->map_to[dirlen] = '/';
+	      strcpy (ptr->map_to + dirlen + 1, to);
+	      free (to);
+	    }	      
+
+	  ptr->map_next = map_list_ptr->map_list_map;
+	  map_list_ptr->map_list_map = ptr;
+
+	  while ((ch = getc (f)) != '\n')
+	    if (ch == EOF)
+	      break;
+	}
+      fclose (f);
+    }
+  
+  map_list_ptr->map_list_next = CPP_OPTIONS (pfile)->map_list;
+  CPP_OPTIONS (pfile)->map_list = map_list_ptr;
+
+  return map_list_ptr->map_list_map;
+}  
+
+/* Remap NAME based on the file_name_map (if any) for LOC. */
+
+static char *
+remap_filename (pfile, name, loc)
+     cpp_reader *pfile;
+     char *name;
+     struct file_name_list *loc;
+{
+  struct file_name_map *map;
+  const char *from, *p, *dir;
+
+  if (! loc->name_map)
+    loc->name_map = read_name_map (pfile,
+				   loc->name
+				   ? loc->name : ".");
+
+  if (loc->name_map == (struct file_name_map *)-1)
+    return name;
+  
+  from = name + strlen (loc->name) + 1;
+  
+  for (map = loc->name_map; map; map = map->map_next)
+    if (!strcmp (map->map_from, from))
+      return map->map_to;
+
+  /* Try to find a mapping file for the particular directory we are
+     looking in.  Thus #include <sys/types.h> will look up sys/types.h
+     in /usr/include/header.gcc and look up types.h in
+     /usr/include/sys/header.gcc.  */
+  p = rindex (name, '/');
+  if (!p)
+    p = name;
+  if (loc && loc->name
+      && strlen (loc->name) == (size_t) (p - name)
+      && !strncmp (loc->name, name, p - name))
+    /* FILENAME is in SEARCHPTR, which we've already checked.  */
+    return name;
+
+  if (p == name)
+    {
+      dir = ".";
+      from = name;
+    }
+  else
+    {
+      char * newdir = (char *) alloca (p - name + 1);
+      bcopy (name, newdir, p - name);
+      newdir[p - name] = '\0';
+      dir = newdir;
+      from = p + 1;
+    }
+  
+  for (map = read_name_map (pfile, dir); map; map = map->map_next)
+    if (! strcmp (map->map_from, name))
+      return map->map_to;
+
+  return name;
+}
+
+/* CYGNUS LOCAL - obscured headers */
+static int
+open_include_file_name (pfile, filename)
+     cpp_reader *pfile;
+     char *filename;
+{
+  return open (filename, O_RDONLY, 0666);
+}
+/* END CYGNUS LOCAL - obscured headers */
+
+/* Read the contents of FD into the buffer on the top of PFILE's stack.
+   IHASH points to the include hash entry for the file associated with
+   FD.
+
+   The caller is responsible for the cpp_push_buffer.  */
+
+int
+finclude (pfile, fd, ihash)
+     cpp_reader *pfile;
+     int fd;
+     struct include_hash *ihash;
+{
+  struct stat st;
+  size_t st_size;
+  long i, length;
+  cpp_buffer *fp;
+#if 0
+  int missing_newline = 0;
+#endif
+
+  if (fstat (fd, &st) < 0)
+    goto perror_fail;
+  
+  fp = CPP_BUFFER (pfile);
+  fp->nominal_fname = fp->fname = ihash->name;
+  fp->ihash = ihash;
+  fp->system_header_p = (ihash->foundhere != ABSOLUTE_PATH
+			 && ihash->foundhere->sysp);
+  fp->lineno = 1;
+  fp->colno = 1;
+  fp->cleanup = file_cleanup;
+
+  /* The ->actual_dir field is only used when ignore_srcdir is not in effect;
+     see do_include */
+  if (!CPP_OPTIONS (pfile)->ignore_srcdir)
+    fp->actual_dir = actual_directory (pfile, fp->fname);
+	
+  if (S_ISREG (st.st_mode))
+    {
+      st_size = (size_t) st.st_size;
+      if (st_size != st.st_size || st_size + 2 < st_size)
+      {
+        cpp_error (pfile, "file `%s' too large", ihash->name);
+	goto fail;
+      }
+      fp->buf = (U_CHAR *) xmalloc (st_size + 2);
+      fp->alimit = fp->buf + st_size + 2;
+      fp->cur = fp->buf;
+      
+      /* Read the file contents, knowing that st_size is an upper bound
+	 on the number of bytes we can read.  */
+      length = safe_read (fd, fp->buf, st_size);
+      fp->rlimit = fp->buf + length;
+      if (length < 0)
+	  goto perror_fail;
+    }
+  else if (S_ISDIR (st.st_mode))
+    {
+      cpp_pop_buffer (pfile);
+      cpp_error (pfile, "directory `%s' specified in #include", ihash->name);
+      goto fail;
+    }
+  else
+    {
+      /* Cannot count its file size before reading.
+	 First read the entire file into heap and
+	 copy them into buffer on stack.  */
+
+      size_t bsize = 2000;
+
+      st_size = 0;
+      fp->buf = (U_CHAR *) xmalloc (bsize + 2);
+
+      for (;;)
+        {
+	  i = safe_read (fd, fp->buf + st_size, bsize - st_size);
+	  if (i < 0)
+	    goto perror_fail;
+	  st_size += i;
+	  if (st_size != bsize)
+	    break;	/* End of file */
+	  bsize *= 2;
+	  fp->buf = (U_CHAR *) xrealloc (fp->buf, bsize + 2);
+	}
+      fp->cur = fp->buf;
+      length = st_size;
+    }
+
+  /* FIXME: Broken in presence of trigraphs (consider ??/<EOF>)
+     and doesn't warn about a missing newline. */
+  if ((length > 0 && fp->buf[length - 1] != '\n')
+      || (length > 1 && fp->buf[length - 2] == '\\'))
+    fp->buf[length++] = '\n';
+
+  fp->buf[length] = '\0';
+  fp->rlimit = fp->buf + length;
+
+  close (fd);
+  pfile->input_stack_listing_current = 0;
+
+#if 0
+  if (!no_trigraphs)
+    trigraph_pcp (fp);
+#endif
+  return 1;
+
+ perror_fail:
+  cpp_pop_buffer (pfile);
+  cpp_error_from_errno (pfile, ihash->name);
+ fail:
+  close (fd);
+  return 0;
+}
+
+static struct file_name_list *
+actual_directory (pfile, fname)
+     cpp_reader *pfile;
+     char *fname;
+{
+  char *last_slash, *dir;
+  size_t dlen;
+  struct file_name_list *x;
+  
+  dir = xstrdup (fname);
+  last_slash = rindex (dir, '/');
+  if (last_slash)
+    {
+      if (last_slash == dir)
+        {
+	  dlen = 1;
+	  last_slash[1] = '\0';
+	}
+      else
+	{
+	  dlen = last_slash - dir;
+	  *last_slash = '\0';
+	}
+    }
+  else
+    {
+      dir[0] = '.';
+      dir[1] = '\0';
+      dlen = 1;
+    }
+
+  if (dlen > pfile->max_include_len)
+    pfile->max_include_len = dlen;
+
+  for (x = pfile->actual_dirs; x; x = x->alloc)
+    if (!strcmp (x->name, dir))
+      {
+	free (dir);
+	return x;
+      }
+
+  /* Not found, make a new one. */
+  x = (struct file_name_list *) xmalloc (sizeof (struct file_name_list));
+  x->name = dir;
+  x->nlen = dlen;
+  x->next = CPP_OPTIONS (pfile)->quote_include;
+  x->alloc = pfile->actual_dirs;
+  x->sysp = 0;
+  x->name_map = NULL;
+
+  pfile->actual_dirs = x;
+  return x;
+}
+
+/* Read LEN bytes at PTR from descriptor DESC, for file FILENAME,
+   retrying if necessary.  If MAX_READ_LEN is defined, read at most
+   that bytes at a time.  Return a negative value if an error occurs,
+   otherwise return the actual number of bytes read,
+   which must be LEN unless end-of-file was reached.  */
+
+static long
+safe_read (desc, ptr, len)
+     int desc;
+     char *ptr;
+     int len;
+{
+  int left, rcount, nchars;
+
+  left = len;
+  while (left > 0) {
+    rcount = left;
+#ifdef MAX_READ_LEN
+    if (rcount > MAX_READ_LEN)
+      rcount = MAX_READ_LEN;
+#endif
+    nchars = read (desc, ptr, rcount);
+    if (nchars < 0)
+      {
+#ifdef EINTR
+	if (errno == EINTR)
+	  continue;
+#endif
+	return nchars;
+      }
+    if (nchars == 0)
+      break;
+    ptr += nchars;
+    left -= nchars;
+  }
+  return len - left;
+}
+
+/* Add output to `deps_buffer' for the -M switch.
+   STRING points to the text to be output.
+   SPACER is ':' for targets, ' ' for dependencies, zero for text
+   to be inserted literally.  */
+
+void
+deps_output (pfile, string, spacer)
+     cpp_reader *pfile;
+     char *string;
+     int spacer;
+{
+  int size;
+  int cr = 0;
+
+  if (!*string)
+    return;
+
+  size = strlen (string);
+
+#ifndef MAX_OUTPUT_COLUMNS
+#define MAX_OUTPUT_COLUMNS 72
+#endif
+  if (pfile->deps_column > 0
+      && (pfile->deps_column + size) > MAX_OUTPUT_COLUMNS)
+    {
+      size += 5;
+      cr = 1;
+      pfile->deps_column = 0;
+    }
+
+  if (pfile->deps_size + size + 8 > pfile->deps_allocated_size)
+    {
+      pfile->deps_allocated_size = (pfile->deps_size + size + 50) * 2;
+      pfile->deps_buffer = (char *) xrealloc (pfile->deps_buffer,
+					      pfile->deps_allocated_size);
+    }
+
+  if (cr)
+    {
+      bcopy (" \\\n  ", &pfile->deps_buffer[pfile->deps_size], 5);
+      pfile->deps_size += 5;
+    }
+  
+  if (spacer == ' ' && pfile->deps_column > 0)
+    pfile->deps_buffer[pfile->deps_size++] = ' ';
+  bcopy (string, &pfile->deps_buffer[pfile->deps_size], size);
+  pfile->deps_size += size;
+  pfile->deps_column += size;
+  if (spacer == ':')
+    pfile->deps_buffer[pfile->deps_size++] = ':';
+  pfile->deps_buffer[pfile->deps_size] = 0;
+}
+
+/* Simplify a path name in place, deleting redundant components.  This
+   reduces OS overhead and guarantees that equivalent paths compare
+   the same (modulo symlinks).
+
+   Transforms made:
+   foo/bar/../quux	foo/quux
+   foo/./bar		foo/bar
+   foo//bar		foo/bar
+   /../quux		/quux
+   //quux		//quux  (POSIX allows leading // as a namespace escape)
+
+   Guarantees no trailing slashes. All transforms reduce the length
+   of the string.
+ */
+static void
+simplify_pathname (path)
+    char *path;
+{
+    char *from, *to;
+    char *base;
+    int absolute = 0;
+
+#if defined _WIN32 || defined __MSDOS__
+    /* Convert all backslashes to slashes. */
+    for (from = path; *from; from++)
+	if (*from == '\\') *from = '/';
+    
+    /* Skip over leading drive letter if present. */
+    if (ISALPHA (path[0]) && path[1] == ':')
+	from = to = &path[2];
+    else
+	from = to = path;
+#else
+    from = to = path;
+#endif
+    
+    /* Remove redundant initial /s.  */
+    if (*from == '/')
+    {
+	absolute = 1;
+	to++;
+	from++;
+	if (*from == '/')
+	{
+	    if (*++from == '/')
+		/* 3 or more initial /s are equivalent to 1 /.  */
+		while (*++from == '/');
+	    else
+		/* On some hosts // differs from /; Posix allows this.  */
+		to++;
+	}
+    }
+    base = to;
+    
+    for (;;)
+    {
+	while (*from == '/')
+	    from++;
+
+	if (from[0] == '.' && from[1] == '/')
+	    from += 2;
+	else if (from[0] == '.' && from[1] == '\0')
+	    goto done;
+	else if (from[0] == '.' && from[1] == '.' && from[2] == '/')
+	{
+	    if (base == to)
+	    {
+		if (absolute)
+		    from += 3;
+		else
+		{
+		    *to++ = *from++;
+		    *to++ = *from++;
+		    *to++ = *from++;
+		    base = to;
+		}
+	    }
+	    else
+	    {
+		to -= 2;
+		while (to > base && *to != '/') to--;
+		if (*to == '/')
+		    to++;
+		from += 3;
+	    }
+	}
+	else if (from[0] == '.' && from[1] == '.' && from[2] == '\0')
+	{
+	    if (base == to)
+	    {
+		if (!absolute)
+		{
+		    *to++ = *from++;
+		    *to++ = *from++;
+		}
+	    }
+	    else
+	    {
+		to -= 2;
+		while (to > base && *to != '/') to--;
+		if (*to == '/')
+		    to++;
+	    }
+	    goto done;
+	}
+	else
+	    /* Copy this component and trailing /, if any.  */
+	    while ((*to++ = *from++) != '/')
+	    {
+		if (!to[-1])
+		{
+		    to--;
+		    goto done;
+		}
+	    }
+	
+    }
+    
+ done:
+    /* Trim trailing slash */
+    if (to[0] == '/' && (!absolute || to > path+1))
+	to--;
+
+    /* Change the empty string to "." so that stat() on the result
+       will always work. */
+    if (to == path)
+      *to++ = '.';
+    
+    *to = '\0';
+
+    return;
+}
+
+/* It is not clear when this should be used if at all, so I've
+   disabled it until someone who understands VMS can look at it. */
+#if 0
+
+/* Under VMS we need to fix up the "include" specification filename.
+
+   Rules for possible conversions
+
+	fullname		tried paths
+
+	name			name
+	./dir/name		[.dir]name
+	/dir/name		dir:name
+	/name			[000000]name, name
+	dir/name		dir:[000000]name, dir:name, dir/name
+	dir1/dir2/name		dir1:[dir2]name, dir1:[000000.dir2]name
+	path:/name		path:[000000]name, path:name
+	path:/dir/name		path:[000000.dir]name, path:[dir]name
+	path:dir/name		path:[dir]name
+	[path]:[dir]name	[path.dir]name
+	path/[dir]name		[path.dir]name
+
+   The path:/name input is constructed when expanding <> includes. */
+
+
+static void
+hack_vms_include_specification (fullname)
+     char *fullname;
+{
+  register char *basename, *unixname, *local_ptr, *first_slash;
+  int f, check_filename_before_returning, must_revert;
+  char Local[512];
+
+  check_filename_before_returning = 0;
+  must_revert = 0;
+  /* See if we can find a 1st slash. If not, there's no path information.  */
+  first_slash = index (fullname, '/');
+  if (first_slash == 0)
+    return 0;				/* Nothing to do!!! */
+
+  /* construct device spec if none given.  */
+
+  if (index (fullname, ':') == 0)
+    {
+
+      /* If fullname has a slash, take it as device spec.  */
+
+      if (first_slash == fullname)
+	{
+	  first_slash = index (fullname+1, '/');	/* 2nd slash ? */
+	  if (first_slash)
+	    *first_slash = ':';				/* make device spec  */
+	  for (basename = fullname; *basename != 0; basename++)
+	    *basename = *(basename+1);			/* remove leading slash  */
+	}
+      else if ((first_slash[-1] != '.')		/* keep ':/', './' */
+	    && (first_slash[-1] != ':')
+	    && (first_slash[-1] != ']'))	/* or a vms path  */
+	{
+	  *first_slash = ':';
+	}
+      else if ((first_slash[1] == '[')		/* skip './' in './[dir'  */
+	    && (first_slash[-1] == '.'))
+	fullname += 2;
+    }
+
+  /* Get part after first ':' (basename[-1] == ':')
+     or last '/' (basename[-1] == '/').  */
+
+  basename = base_name (fullname);
+
+  local_ptr = Local;			/* initialize */
+
+  /* We are trying to do a number of things here.  First of all, we are
+     trying to hammer the filenames into a standard format, such that later
+     processing can handle them.
+     
+     If the file name contains something like [dir.], then it recognizes this
+     as a root, and strips the ".]".  Later processing will add whatever is
+     needed to get things working properly.
+     
+     If no device is specified, then the first directory name is taken to be
+     a device name (or a rooted logical).  */
+
+  /* Point to the UNIX filename part (which needs to be fixed!)
+     but skip vms path information.
+     [basename != fullname since first_slash != 0].  */
+
+  if ((basename[-1] == ':')		/* vms path spec.  */
+      || (basename[-1] == ']')
+      || (basename[-1] == '>'))
+    unixname = basename;
+  else
+    unixname = fullname;
+
+  if (*unixname == '/')
+    unixname++;
+
+  /* If the directory spec is not rooted, we can just copy
+     the UNIX filename part and we are done.  */
+
+  if (((basename - fullname) > 1)
+     && (  (basename[-1] == ']')
+        || (basename[-1] == '>')))
+    {
+      if (basename[-2] != '.')
+	{
+
+	/* The VMS part ends in a `]', and the preceding character is not a `.'.
+	   -> PATH]:/name (basename = '/name', unixname = 'name')
+	   We strip the `]', and then splice the two parts of the name in the
+	   usual way.  Given the default locations for include files in cccp.c,
+	   we will only use this code if the user specifies alternate locations
+	   with the /include (-I) switch on the command line.  */
+
+	  basename -= 1;	/* Strip "]" */
+	  unixname--;		/* backspace */
+	}
+      else
+	{
+
+	/* The VMS part has a ".]" at the end, and this will not do.  Later
+	   processing will add a second directory spec, and this would be a syntax
+	   error.  Thus we strip the ".]", and thus merge the directory specs.
+	   We also backspace unixname, so that it points to a '/'.  This inhibits the
+	   generation of the 000000 root directory spec (which does not belong here
+	   in this case).  */
+
+	  basename -= 2;	/* Strip ".]" */
+	  unixname--;		/* backspace */
+	}
+    }
+
+  else
+
+    {
+
+      /* We drop in here if there is no VMS style directory specification yet.
+         If there is no device specification either, we make the first dir a
+         device and try that.  If we do not do this, then we will be essentially
+         searching the users default directory (as if they did a #include "asdf.h").
+        
+         Then all we need to do is to push a '[' into the output string. Later
+         processing will fill this in, and close the bracket.  */
+
+      if ((unixname != fullname)	/* vms path spec found.  */
+	 && (basename[-1] != ':'))
+	*local_ptr++ = ':';		/* dev not in spec.  take first dir */
+
+      *local_ptr++ = '[';		/* Open the directory specification */
+    }
+
+    if (unixname == fullname)		/* no vms dir spec.  */
+      {
+	must_revert = 1;
+	if ((first_slash != 0)		/* unix dir spec.  */
+	    && (*unixname != '/')	/* not beginning with '/'  */
+	    && (*unixname != '.'))	/* or './' or '../'  */
+	  *local_ptr++ = '.';		/* dir is local !  */
+      }
+
+  /* at this point we assume that we have the device spec, and (at least
+     the opening "[" for a directory specification.  We may have directories
+     specified already.
+
+     If there are no other slashes then the filename will be
+     in the "root" directory.  Otherwise, we need to add
+     directory specifications.  */
+
+  if (index (unixname, '/') == 0)
+    {
+      /* if no directories specified yet and none are following.  */
+      if (local_ptr[-1] == '[')
+	{
+	  /* Just add "000000]" as the directory string */
+	  strcpy (local_ptr, "000000]");
+	  local_ptr += strlen (local_ptr);
+	  check_filename_before_returning = 1; /* we might need to fool with this later */
+	}
+    }
+  else
+    {
+
+      /* As long as there are still subdirectories to add, do them.  */
+      while (index (unixname, '/') != 0)
+	{
+	  /* If this token is "." we can ignore it
+	       if it's not at the beginning of a path.  */
+	  if ((unixname[0] == '.') && (unixname[1] == '/'))
+	    {
+	      /* remove it at beginning of path.  */
+	      if (  ((unixname == fullname)		/* no device spec  */
+		    && (fullname+2 != basename))	/* starts with ./ */
+							/* or  */
+		 || ((basename[-1] == ':')		/* device spec  */
+		    && (unixname-1 == basename)))	/* and ./ afterwards  */
+		*local_ptr++ = '.';		 	/* make '[.' start of path.  */
+	      unixname += 2;
+	      continue;
+	    }
+
+	  /* Add a subdirectory spec. Do not duplicate "." */
+	  if (  local_ptr[-1] != '.'
+	     && local_ptr[-1] != '['
+	     && local_ptr[-1] != '<')
+	    *local_ptr++ = '.';
+
+	  /* If this is ".." then the spec becomes "-" */
+	  if (  (unixname[0] == '.')
+	     && (unixname[1] == '.')
+	     && (unixname[2] == '/'))
+	    {
+	      /* Add "-" and skip the ".." */
+	      if ((local_ptr[-1] == '.')
+		  && (local_ptr[-2] == '['))
+		local_ptr--;			/* prevent [.-  */
+	      *local_ptr++ = '-';
+	      unixname += 3;
+	      continue;
+	    }
+
+	  /* Copy the subdirectory */
+	  while (*unixname != '/')
+	    *local_ptr++= *unixname++;
+
+	  unixname++;			/* Skip the "/" */
+	}
+
+      /* Close the directory specification */
+      if (local_ptr[-1] == '.')		/* no trailing periods */
+	local_ptr--;
+
+      if (local_ptr[-1] == '[')		/* no dir needed */
+	local_ptr--;
+      else
+	*local_ptr++ = ']';
+    }
+
+  /* Now add the filename.  */
+
+  while (*unixname)
+    *local_ptr++ = *unixname++;
+  *local_ptr = 0;
+
+  /* Now append it to the original VMS spec.  */
+
+  strcpy ((must_revert==1)?fullname:basename, Local);
+
+  /* If we put a [000000] in the filename, try to open it first. If this fails,
+     remove the [000000], and return that name.  This provides flexibility
+     to the user in that they can use both rooted and non-rooted logical names
+     to point to the location of the file.  */
+
+  if (check_filename_before_returning)
+    {
+      f = open (fullname, O_RDONLY, 0666);
+      if (f >= 0)
+	{
+	  /* The file name is OK as it is, so return it as is.  */
+	  close (f);
+	  return 1;
+	}
+
+      /* The filename did not work.  Try to remove the [000000] from the name,
+	 and return it.  */
+
+      basename = index (fullname, '[');
+      local_ptr = index (fullname, ']') + 1;
+      strcpy (basename, local_ptr);		/* this gets rid of it */
+
+    }
+
+  return 1;
+}
+#endif	/* VMS */