Initial revision

1 files changed, 401 insertions, 0 deletions

diff --git a/dir.c b/dir.c
new file mode 100644
index 0000000..e3d3fa5
--- /dev/null
+++ b/dir.c
@@ -0,0 +1,401 @@
+/* Directory hashing for GNU Make.
+Copyright (C) 1988, 1989, 1991 Free Software Foundation, Inc.
+This file is part of GNU Make.
+
+GNU Make 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.
+
+GNU Make 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 GNU Make; see the file COPYING.  If not, write to
+the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#include "make.h"
+
+#if defined (USGr3) && !defined (DIRENT)
+#define DIRENT
+#endif /* USGr3 */
+#if defined (Xenix) && !defined (SYSNDIR)
+#define SYSNDIR
+#endif /* Xenix */
+
+#if defined (POSIX) || defined (DIRENT) || defined (__GNU_LIBRARY__)
+#include <dirent.h>
+#define direct dirent
+#define D_NAMLEN(d) strlen((d)->d_name)
+#else /* not POSIX or DIRENT */
+#define D_NAMLEN(d) ((d)->d_namlen)
+#if defined (USG) && !defined (sgi)
+#if defined (SYSNDIR)
+#include <sys/ndir.h>
+#else /* SYSNDIR */
+#include "ndir.h"
+#endif /* not SYSNDIR */
+#else /* not USG */
+#include <sys/dir.h>
+#endif /* USG */
+#endif /* POSIX or DIRENT or __GNU_LIBRARY__ */
+
+#if defined (POSIX) && !defined (__GNU_LIBRARY__)
+/* Posix does not require that the d_ino field be present, and some
+   systems do not provide it. */
+#define REAL_DIR_ENTRY(dp) 1
+#else
+#define REAL_DIR_ENTRY(dp) (dp->d_ino != 0)
+#endif /* POSIX */
+
+/* Hash table of directories.  */
+
+struct directory
+  {
+    struct directory *next;
+    char *name;			/* Name of the directory.  */
+    struct dirfile **files;	/* Files in this directory.  */
+    DIR *dirstream;		/* Stream reading this directory.  */
+  };
+
+#ifndef	DIRECTORY_BUCKETS
+#define DIRECTORY_BUCKETS 23
+#endif
+
+static struct directory *directories[DIRECTORY_BUCKETS];
+
+
+/* Never have more than this many directories open at once.  */
+
+#define MAX_OPEN_DIRECTORIES 10
+
+static unsigned int open_directories = 0;
+
+
+/* Hash table of files in each directory.  */
+
+struct dirfile
+  {
+    struct dirfile *next;
+    char *name;			/* Name of the file.  */
+    char impossible;		/* This file is impossible.  */
+  };
+
+#ifndef	DIRFILE_BUCKETS
+#define DIRFILE_BUCKETS 1007
+#endif
+
+/* Find the directory named NAME and return its `struct directory'.  */
+
+static struct directory *
+find_directory (name)
+     register char *name;
+{
+  register unsigned int hash = 0;
+  register char *p;
+  register struct directory *dir;
+
+  for (p = name; *p != '\0'; ++p)
+    HASH (hash, *p);
+  hash %= DIRECTORY_BUCKETS;
+
+  for (dir = directories[hash]; dir != 0; dir = dir->next)
+    if (streq (dir->name, name))
+      break;
+
+  if (dir == 0)
+    {
+      /* The directory was not found.  Create a new entry
+	 for it and start its directory stream reading.  */
+      dir = (struct directory *) xmalloc (sizeof (struct directory));
+      dir->next = directories[hash];
+      directories[hash] = dir;
+      dir->name = savestring (name, p - name);
+      dir->dirstream = opendir (name);
+      if (dir->dirstream == 0)
+	/* Couldn't open the directory.  Mark this by
+	   setting the `files' member to a nil pointer.  */
+	dir->files = 0;
+      else
+	{
+	  /* Allocate an array of hash buckets for files and zero it.  */
+	  dir->files = (struct dirfile **)
+	    xmalloc (sizeof (struct dirfile) * DIRFILE_BUCKETS);
+	  bzero ((char *) dir->files,
+		 sizeof (struct dirfile) * DIRFILE_BUCKETS);
+
+	  /* Keep track of how many directories are open.  */
+	  ++open_directories;
+	  if (open_directories == MAX_OPEN_DIRECTORIES)
+	    /* Read the entire directory and then close it.  */
+	    (void) dir_file_exists_p (dir->name, (char *) 0);
+	}
+    }
+
+  return dir;
+}
+
+/* Return 1 if the name FILENAME in directory DIRNAME
+   is entered in the dir hash table.
+   FILENAME must contain no slashes.  */
+
+int
+dir_file_exists_p (dirname, filename)
+     register char *dirname;
+     register char *filename;
+{
+  register unsigned int hash;
+  register char *p;
+  register struct directory *dir;
+  register struct dirfile *df;
+  register struct direct *d;
+  dir = find_directory (dirname);
+
+  if (dir->files == 0)
+    /* The directory could not be opened.  */
+    return 0;
+
+  hash = 0;
+  if (filename != 0)
+    {
+      if (*filename == '\0')
+	/* Checking if the directory exists.  */
+	return 1;
+
+      for (p = filename; *p != '\0'; ++p)
+	HASH (hash, *p);
+      hash %= DIRFILE_BUCKETS;
+
+      /* Search the list of hashed files.  */
+
+      for (df = dir->files[hash]; df != 0; df = df->next)
+	if (streq (df->name, filename))
+	  return !df->impossible;
+    }
+
+  /* The file was not found in the hashed list.
+     Try to read the directory further.  */
+
+  if (dir->dirstream == 0)
+    /* The directory has been all read in.  */
+    return 0;
+
+  while ((d = readdir (dir->dirstream)) != 0)
+    {
+      /* Enter the file in the hash table.  */
+      register unsigned int newhash = 0;
+      register unsigned int i;
+
+      if (!REAL_DIR_ENTRY (d))
+	continue;
+
+      for (i = 0; i < D_NAMLEN(d); ++i)
+	HASH (newhash, d->d_name[i]);
+      newhash %= DIRFILE_BUCKETS;
+
+      df = (struct dirfile *) xmalloc (sizeof (struct dirfile));
+      df->next = dir->files[newhash];
+      dir->files[newhash] = df;
+      df->name = savestring (d->d_name, D_NAMLEN(d));
+      df->impossible = 0;
+
+      /* Check if the name matches the one we're searching for.  */
+      if (filename != 0
+	  && newhash == hash && streq (d->d_name, filename))
+	return 1;
+    }
+
+  /* If the directory has been completely read in,
+     close the stream and reset the pointer to nil.  */
+  if (d == 0)
+    {
+      --open_directories;
+      closedir (dir->dirstream);
+      dir->dirstream = 0;
+    }
+
+  return 0;
+}
+
+/* Return 1 if the file named NAME exists.  */
+
+int
+file_exists_p (name)
+     register char *name;
+{
+  char *dirend;
+  char *dirname;
+
+#ifndef	NO_ARCHIVES
+  if (ar_name (name))
+    return ar_member_date (name) != (time_t) -1;
+#endif
+
+  dirend = rindex (name, '/');
+  if (dirend == 0)
+    return dir_file_exists_p (".", name);
+
+  dirname = (char *) alloca (dirend - name + 1);
+  bcopy (name, dirname, dirend - name);
+  dirname[dirend - name] = '\0';
+  return dir_file_exists_p (dirname, dirend + 1);
+}
+
+/* Mark FILENAME as `impossible' for `file_impossible_p'.
+   This means an attempt has been made to search for FILENAME
+   as an intermediate file, and it has failed.  */
+
+void
+file_impossible (filename)
+     register char *filename;
+{
+  char *dirend;
+  register char *p = filename;
+  register unsigned int hash;
+  register struct directory *dir;
+  register struct dirfile *new;
+
+  dirend = rindex (p, '/');
+  if (dirend == 0)
+    dir = find_directory (".");
+  else
+    {
+      char *dirname = (char *) alloca (dirend - p + 1);
+      bcopy (p, dirname, dirend - p);
+      dirname[dirend - p] = '\0';
+      dir = find_directory (dirname);
+      filename = p = dirend + 1;
+    }
+
+  for (hash = 0; *p != '\0'; ++p)
+    HASH (hash, *p);
+  hash %= DIRFILE_BUCKETS;
+
+  if (dir->files == 0)
+    {
+      /* The directory was not opened; we must allocate the hash buckets.  */
+      dir->files = (struct dirfile **)
+	xmalloc (sizeof (struct dirfile) * DIRFILE_BUCKETS);
+      bzero ((char *) dir->files, sizeof (struct dirfile) * DIRFILE_BUCKETS);
+    }
+
+  /* Make a new entry and put it in the table.  */
+
+  new = (struct dirfile *) xmalloc (sizeof (struct dirfile));
+  new->next = dir->files[hash];
+  dir->files[hash] = new;
+  new->name = savestring (filename, strlen (filename));
+  new->impossible = 1;
+}
+
+/* Return nonzero if FILENAME has been marked impossible.  */
+
+int
+file_impossible_p (filename)
+     char *filename;
+{
+  char *dirend;
+  register char *p = filename;
+  register unsigned int hash;
+  register struct directory *dir;
+  register struct dirfile *next;
+
+  dirend = rindex (filename, '/');
+  if (dirend == 0)
+    dir = find_directory (".");
+  else
+    {
+      char *dirname = (char *) alloca (dirend - filename + 1);
+      bcopy (p, dirname, dirend - p);
+      dirname[dirend - p] = '\0';
+      dir = find_directory (dirname);
+      p = dirend + 1;
+    }
+
+  if (dir->files == 0)
+    /* There are no files entered for this directory.  */
+    return 0;
+
+  for (hash = 0; *p != '\0'; ++p)
+    HASH (hash, *p);
+  hash %= DIRFILE_BUCKETS;
+
+  for (next = dir->files[hash]; next != 0; next = next->next)
+    if (streq (filename, next->name))
+      return next->impossible;
+
+  return 0;
+}
+
+/* Return the already allocated name in the
+   directory hash table that matches DIR.  */
+
+char *
+dir_name (dir)
+     char *dir;
+{
+  return find_directory (dir)->name;
+}
+
+/* Print the data base of directories.  */
+
+void
+print_dir_data_base ()
+{
+  register unsigned int i, dirs, files, impossible;
+  register struct directory *dir;
+
+  puts ("\n# Directories\n");
+
+  dirs = files = impossible = 0;
+  for (i = 0; i < DIRECTORY_BUCKETS; ++i)
+    for (dir = directories[i]; dir != 0; dir = dir->next)
+      {
+	++dirs;
+	if (dir->files == 0)
+	  printf ("# %s: could not be opened.\n", dir->name);
+	else
+	  {
+	    register unsigned int f = 0, im = 0;
+	    register unsigned int j;
+	    register struct dirfile *df;
+	    for (j = 0; j < DIRFILE_BUCKETS; ++j)
+	      for (df = dir->files[j]; df != 0; df = df->next)
+		if (df->impossible)
+		  ++im;
+		else
+		  ++f;
+	    printf ("# %s: ", dir->name);
+	    if (f == 0)
+	      fputs ("No", stdout);
+	    else
+	      printf ("%u", f);
+	    fputs (" files, ", stdout);
+	    if (im == 0)
+	      fputs ("no", stdout);
+	    else
+	      printf ("%u", im);
+	    fputs (" impossibilities", stdout);
+	    if (dir->dirstream == 0)
+	      puts (".");
+	    else
+	      puts (" so far.");
+	    files += f;
+	    impossible += im;
+	  }
+      }
+
+  fputs ("\n# ", stdout);
+  if (files == 0)
+    fputs ("No", stdout);
+  else
+    printf ("%u", files);
+  fputs (" files, ", stdout);
+  if (impossible == 0)
+    fputs ("no", stdout);
+  else
+    printf ("%u", impossible);
+  printf (" impossibilities in %u directories.\n", dirs);
+}