This is dir.c in view mode; [Download] [Up]
/* Directory hashing for GNU Make.
Copyright (C) 1988, 1989, 1991, 1992, 1993 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>
#ifndef __GNU_LIBRARY__
#define D_NAMLEN(d) strlen((d)->d_name)
#else
#define D_NAMLEN(d) ((d)->d_namlen)
#endif
#else /* not POSIX or DIRENT */
#define direct 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. */
#ifndef DIRECTORY_BUCKETS
#define DIRECTORY_BUCKETS 199
#endif
struct directory_contents
{
struct directory_contents *next;
int dev, ino; /* Device and inode numbers of this dir. */
struct dirfile **files; /* Files in this directory. */
DIR *dirstream; /* Stream reading this directory. */
};
/* Table of directory contents hashed by device and inode number. */
static struct directory_contents *directories_contents[DIRECTORY_BUCKETS];
struct directory
{
struct directory *next;
char *name; /* Name of the directory. */
/* The directory's contents. This data may be shared by several
entries in the hash table, which refer to the same directory
(identified uniquely by `dev' and `ino') under different names. */
struct directory_contents *contents;
};
/* Table of directories hashed by name. */
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 107
#endif
static int dir_contents_file_exists_p ();
/* 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)
{
struct stat st;
/* The directory was not found. Create a new entry for it. */
dir = (struct directory *) xmalloc (sizeof (struct directory));
dir->next = directories[hash];
directories[hash] = dir;
dir->name = savestring (name, p - name);
/* The directory is not in the name hash table.
Find its device and inode numbers, and look it up by them. */
if (stat (name, &st) < 0)
/* Couldn't stat the directory. Mark this by
setting the `contents' member to a nil pointer. */
dir->contents = 0;
else
{
/* Search the contents hash table; device and inode are the key. */
struct directory_contents *dc;
hash = ((unsigned int) st.st_dev << 16) | (unsigned int) st.st_ino;
hash %= DIRECTORY_BUCKETS;
for (dc = directories_contents[hash]; dc != 0; dc = dc->next)
if (dc->dev == st.st_dev && dc->ino == st.st_ino)
break;
if (dc == 0)
{
/* Nope; this really is a directory we haven't seen before. */
dc = (struct directory_contents *)
xmalloc (sizeof (struct directory_contents));
/* Enter it in the contents hash table. */
dc->dev = st.st_dev;
dc->ino = st.st_ino;
dc->next = directories_contents[hash];
directories_contents[hash] = dc;
dc->dirstream = opendir (name);
if (dc->dirstream == 0)
/* Couldn't open the directory. Mark this by
setting the `files' member to a nil pointer. */
dc->files = 0;
else
{
/* Allocate an array of buckets for files and zero it. */
dc->files = (struct dirfile **)
xmalloc (sizeof (struct dirfile *) * DIRFILE_BUCKETS);
bzero ((char *) dc->files,
sizeof (struct dirfile *) * DIRFILE_BUCKETS);
/* Keep track of how many directories are open. */
++open_directories;
if (open_directories == MAX_OPEN_DIRECTORIES)
/* We have too many directories open already.
Read the entire directory and then close it. */
(void) dir_contents_file_exists_p (dc, (char *) 0);
}
}
/* Point the name-hashed entry for DIR at its contents data. */
dir->contents = dc;
}
}
return dir;
}
/* Return 1 if the name FILENAME is entered in DIR's hash table.
FILENAME must contain no slashes. */
static int
dir_contents_file_exists_p (dir, filename)
register struct directory_contents *dir;
register char *filename;
{
register unsigned int hash;
register char *p;
register struct dirfile *df;
register struct dirent *d;
if (dir == 0 || dir->files == 0)
/* The directory could not be stat'd or 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 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;
{
return dir_contents_file_exists_p (find_directory (dirname)->contents,
filename);
}
/* 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->contents == 0)
{
/* The directory could not be stat'd. We allocate a contents
structure for it, but leave it out of the contents hash table. */
dir->contents = (struct directory_contents *)
xmalloc (sizeof (struct directory_contents));
dir->contents->dev = dir->contents->ino = 0;
dir->contents->files = 0;
dir->contents->dirstream = 0;
}
if (dir->contents->files == 0)
{
/* The directory was not opened; we must allocate the hash buckets. */
dir->contents->files = (struct dirfile **)
xmalloc (sizeof (struct dirfile) * DIRFILE_BUCKETS);
bzero ((char *) dir->contents->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->contents->files[hash];
dir->contents->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_contents *dir;
register struct dirfile *next;
dirend = rindex (filename, '/');
if (dirend == 0)
dir = find_directory (".")->contents;
else
{
char *dirname = (char *) alloca (dirend - filename + 1);
bcopy (p, dirname, dirend - p);
dirname[dirend - p] = '\0';
dir = find_directory (dirname)->contents;
p = dirend + 1;
}
if (dir == 0 || 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->contents == 0)
printf ("# %s: could not be stat'd.\n", dir->name);
else if (dir->contents->files == 0)
printf ("# %s (device %d, inode %d): could not be opened.\n",
dir->name, dir->contents->dev, dir->contents->ino);
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->contents->files[j]; df != 0; df = df->next)
if (df->impossible)
++im;
else
++f;
printf ("# %s (device %d, inode %d): ",
dir->name, dir->contents->dev, dir->contents->ino);
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->contents->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);
}
/* Hooks for globbing. */
#include <glob.h>
/* Structure describing state of iterating through a directory hash table. */
struct dirstream
{
struct directory_contents *contents; /* The directory being read. */
unsigned int bucket; /* Current hash bucket. */
struct dirfile *elt; /* Current elt in bucket. */
};
/* Forward declarations. */
static __ptr_t open_dirstream __P ((const char *));
static const char *read_dirstream __P ((__ptr_t));
static __ptr_t
open_dirstream (directory)
const char *directory;
{
struct dirstream *new;
struct directory *dir = find_directory (directory);
if (dir->contents == 0 || dir->contents->files == 0)
/* DIR->contents is nil if the directory could not be stat'd.
DIR->contents->files is nil if it could not be opened. */
return 0;
/* Read all the contents of the directory now. There is no benefit
in being lazy, since glob will want to see every file anyway. */
(void) dir_contents_file_exists_p (dir->contents, (char *) 0);
new = (struct dirstream *) xmalloc (sizeof (struct dirstream));
new->contents = dir->contents;
new->bucket = 0;
new->elt = new->contents->files[0];
return (__ptr_t) new;
}
static const char *
read_dirstream (stream)
__ptr_t stream;
{
struct dirstream *const ds = (struct dirstream *) stream;
register struct dirfile *df;
while (ds->bucket < DIRFILE_BUCKETS)
{
while ((df = ds->elt) != 0)
{
ds->elt = df->next;
if (!df->impossible)
return df->name;
}
ds->elt = ds->contents->files[++ds->bucket];
}
return 0;
}
void
init_dir ()
{
__glob_opendir_hook = open_dirstream;
__glob_readdir_hook = read_dirstream;
__glob_closedir_hook = (void (*) __P ((__ptr_t stream))) free;
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.