-
/*
- * $Id: filemap.cc,v 1.37 2001/01/09 14:11:15 hno Exp $
- *
- * DEBUG: section 8 Swap File Bitmap
+ * DEBUG: section 08 Swap File Bitmap
* AUTHOR: Harvest Derived
*
- * SQUID Internet Object Cache http://squid.nlanr.net/Squid/
+ * SQUID Web Proxy Cache http://www.squid-cache.org/
* ----------------------------------------------------------
*
- * Squid is the result of efforts by numerous individuals from the
- * Internet community. Development is led by Duane Wessels of the
- * National Laboratory for Applied Network Research and funded by the
- * National Science Foundation. Squid is Copyrighted (C) 1998 by
- * the Regents of the University of California. Please see the
- * COPYRIGHT file for full details. Squid incorporates software
- * developed and/or copyrighted by other sources. Please see the
- * CREDITS file for full details.
+ * Squid is the result of efforts by numerous individuals from
+ * the Internet community; see the CONTRIBUTORS file for full
+ * details. Many organizations have provided support for Squid's
+ * development; see the SPONSORS file for full details. Squid is
+ * Copyrighted (C) 2001 by the Regents of the University of
+ * California; see the COPYRIGHT file for full details. Squid
+ * incorporates software developed and/or copyrighted by other
+ * sources; see the CREDITS file for full details.
*
* 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 of the License, 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, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
*/
#include "squid.h"
+#include "Debug.h"
+#include "FileMap.h"
/* Number of bits in a long */
#if SIZEOF_LONG == 8
#define FM_INITIAL_NUMBER (1<<14)
-fileMap *
-file_map_create(void)
+FileMap::FileMap() :
+ capacity_(FM_INITIAL_NUMBER), usedSlots_(0),
+ nwords(capacity_ >> LONG_BIT_SHIFT)
{
- fileMap *fm = xcalloc(1, sizeof(fileMap));
- fm->max_n_files = FM_INITIAL_NUMBER;
- fm->nwords = fm->max_n_files >> LONG_BIT_SHIFT;
- debug(8, 3) ("file_map_create: creating space for %d files\n", fm->max_n_files);
- debug(8, 5) ("--> %d words of %d bytes each\n",
- fm->nwords, sizeof(*fm->file_map));
- fm->file_map = xcalloc(fm->nwords, sizeof(*fm->file_map));
- /* XXX account fm->file_map */
- return fm;
+ debugs(8, 3, HERE << "creating space for " << capacity_ << " files");
+ debugs(8, 5, "--> " << nwords << " words of " << sizeof(*bitmap) << " bytes each");
+ bitmap = (unsigned long *)xcalloc(nwords, sizeof(*bitmap));
}
-static void
-file_map_grow(fileMap * fm)
+void
+FileMap::grow()
{
- int old_sz = fm->nwords * sizeof(*fm->file_map);
- void *old_map = fm->file_map;
- fm->max_n_files <<= 1;
- assert(fm->max_n_files <= (1 << 24)); /* swap_filen is 25 bits, signed */
- fm->nwords = fm->max_n_files >> LONG_BIT_SHIFT;
- debug(8, 3) ("file_map_grow: creating space for %d files\n", fm->max_n_files);
- fm->file_map = xcalloc(fm->nwords, sizeof(*fm->file_map));
- debug(8, 3) ("copying %d old bytes\n", old_sz);
- xmemcpy(fm->file_map, old_map, old_sz);
+ int old_sz = nwords * sizeof(*bitmap);
+ void *old_map = bitmap;
+ capacity_ <<= 1;
+ assert(capacity_ <= (1 << 24)); /* swap_filen is 25 bits, signed */
+ nwords = capacity_ >> LONG_BIT_SHIFT;
+ debugs(8, 3, HERE << " creating space for " << capacity_ << " files");
+ debugs(8, 5, "--> " << nwords << " words of " << sizeof(*bitmap) << " bytes each");
+ bitmap = (unsigned long *)xcalloc(nwords, sizeof(*bitmap));
+ debugs(8, 3, "copying " << old_sz << " old bytes");
+ memcpy(bitmap, old_map, old_sz);
xfree(old_map);
- /* XXX account fm->file_map */
+ /* XXX account fm->bitmap */
}
-int
-file_map_bit_set(fileMap * fm, int file_number)
+bool
+FileMap::setBit(sfileno file_number)
{
unsigned long bitmask = (1L << (file_number & LONG_BIT_MASK));
- while (file_number >= fm->max_n_files)
- file_map_grow(fm);
- fm->file_map[file_number >> LONG_BIT_SHIFT] |= bitmask;
- fm->n_files_in_map++;
+
+ while (file_number >= capacity_)
+ grow();
+
+ bitmap[file_number >> LONG_BIT_SHIFT] |= bitmask;
+
+ usedSlots_++;
+
return file_number;
}
/*
- * WARNING: file_map_bit_reset does not perform array bounds
+ * WARNING: clearBit does not perform array bounds
* checking! It assumes that 'file_number' is valid, and that the
* bit is already set. The caller must verify both of those
- * conditions by calling file_map_bit_test() first.
+ * conditions by calling testBit
+ * () first.
*/
void
-file_map_bit_reset(fileMap * fm, int file_number)
+FileMap::clearBit(sfileno file_number)
{
unsigned long bitmask = (1L << (file_number & LONG_BIT_MASK));
- fm->file_map[file_number >> LONG_BIT_SHIFT] &= ~bitmask;
- fm->n_files_in_map--;
+ bitmap[file_number >> LONG_BIT_SHIFT] &= ~bitmask;
+ usedSlots_--;
}
-int
-file_map_bit_test(fileMap * fm, int file_number)
+bool
+FileMap::testBit(sfileno file_number) const
{
unsigned long bitmask = (1L << (file_number & LONG_BIT_MASK));
- if (file_number >= fm->max_n_files)
- return 0;
+
+ if (file_number >= capacity_)
+ return 0;
+
/* be sure the return value is an int, not a u_long */
- return (fm->file_map[file_number >> LONG_BIT_SHIFT] & bitmask ? 1 : 0);
+ return (bitmap[file_number >> LONG_BIT_SHIFT] & bitmask ? 1 : 0);
}
-int
-file_map_allocate(fileMap * fm, int suggestion)
+sfileno
+FileMap::allocate(sfileno suggestion)
{
int word;
- int bit;
- int count;
- if (suggestion >= fm->max_n_files)
- suggestion = 0;
- if (!file_map_bit_test(fm, suggestion))
- return suggestion;
+
+ if (suggestion >= capacity_)
+ suggestion = 0;
+
+ if (!testBit(suggestion))
+ return suggestion;
+
word = suggestion >> LONG_BIT_SHIFT;
- for (count = 0; count < fm->nwords; count++) {
- if (fm->file_map[word] != ALL_ONES)
- break;
- word = (word + 1) % fm->nwords;
+
+ for (unsigned int count = 0; count < nwords; count++) {
+ if (bitmap[word] != ALL_ONES)
+ break;
+
+ word = (word + 1) % nwords;
}
- for (bit = 0; bit < BITS_IN_A_LONG; bit++) {
- suggestion = ((unsigned long) word << LONG_BIT_SHIFT) | bit;
- if (!file_map_bit_test(fm, suggestion)) {
- return suggestion;
- }
+
+ for (unsigned char bit = 0; bit < BITS_IN_A_LONG; bit++) {
+ suggestion = ((unsigned long) word << LONG_BIT_SHIFT) | bit;
+
+ if (!testBit(suggestion)) {
+ return suggestion;
+ }
}
- debug(8, 3) ("growing from file_map_allocate\n");
- file_map_grow(fm);
- return file_map_allocate(fm, fm->max_n_files >> 1);
-}
-void
-filemapFreeMemory(fileMap * fm)
-{
- safe_free(fm->file_map);
- safe_free(fm);
+ grow();
+ return allocate(capacity_ >> 1);
}
-#ifdef TEST
-
-#define TEST_SIZE 1<<16
-main(argc, argv)
+FileMap::~FileMap()
{
- int i;
-
- fm = file_map_create(TEST_SIZE);
-
- for (i = 0; i < TEST_SIZE; ++i) {
- file_map_bit_set(i);
- assert(file_map_bit_test(i));
- file_map_bit_reset(i);
- }
+ safe_free(bitmap);
}
-#endif
projects / thirdparty / squid.git / blobdiff