summaryrefslogtreecommitdiff
path: root/dir.c
diff options
context:
space:
mode:
Diffstat (limited to 'dir.c')
-rw-r--r--dir.c401
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);
+}