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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2017 by Michael Sevakis
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef FS_DEFINES_H
#define FS_DEFINES_H
/** Tuneable parameters **/
#if 0
/* Define this just in case you're doing something that may crash a lot and
want less write caching */
#define FS_MIN_WRITECACHING
#endif
#ifndef MAX_PATH
#define MAX_PATH 260
#endif
#define MAX_COMPNAME 260
/* limits for number of open descriptors - if you increase these values, make
certain that the disk cache has enough available buffers */
#if MEMORYSIZE < 8
#define MAX_OPEN_FILES 11
#define MAX_OPEN_DIRS 12
#else
#define MAX_OPEN_FILES 31
#define MAX_OPEN_DIRS 32
#endif /* MEMORYSIZE */
/* internal functions open streams as well; make sure they don't fail if all
user descs are busy; this needs to be at least the greatest quantity needed
at once by all internal functions */
#define MOUNT_AUX_FILEOBJS 1
#ifdef HAVE_DIRCACHE
#define DIRCACHE_AUX_FILEOBJS 1
#else
#define DIRCACHE_AUX_FILEOBJS 0
#endif
#define AUX_FILEOBJS (2+DIRCACHE_AUX_FILEOBJS+MOUNT_AUX_FILEOBJS)
/* number of components statically allocated to handle the vast majority
of path depths; should maybe be tuned for >= 90th percentile but for now,
imma just guessing based on something like:
root + 'Music' + 'Artist' + 'Album' + 'Disc N' + filename */
#define STATIC_PATHCOMP_NUM 6
/* unsigned value that will also hold the off_t range we need without
overflow */
#define file_size_t uint32_t
#ifdef __USE_FILE_OFFSET64
/* if we want, we can deal with files up to 2^32-1 bytes-- the full FAT16/32
range */
#define FILE_SIZE_MAX (0xffffffffu)
#else
/* file contents and size will be preserved by the APIs so long as ftruncate()
isn't used; bytes passed 2^31-1 will not accessible nor will writes succeed
that would extend the file beyond the max for a 32-bit off_t */
#define FILE_SIZE_MAX (0x7fffffffu)
#endif
/* if file is "large(ish)", then get rid of the contents now rather than
lazily when the file is synced or closed in order to free-up space */
#define O_TRUNC_THRESH 65536
/* This needs enough for all file handles to have a buffer in the worst case
* plus at least one reserved exclusively for the cache client and a couple
* for other file system code. The buffers are put to use by the cache if not
* taken for another purpose (meaning nothing is wasted sitting fallow).
*
* One map per volume is maintained in order to avoid collisions between
* volumes that would slow cache probing. IOC_MAP_NUM_ENTRIES is the number
* for each map per volume. The buffers themselves are shared.
*/
#if MEMORYSIZE < 8
#define DC_NUM_ENTRIES 32
#define DC_MAP_NUM_ENTRIES 128
#else
#define DC_NUM_ENTRIES 64
#define DC_MAP_NUM_ENTRIES 256
#endif /* MEMORYSIZE */
/* increasing this will increase the total memory used by the cache; the
cache, as noted in disk_cache.h, has other minimum requirements that may
prevent reducing its number of entries in order to compensate */
#ifndef SECTOR_SIZE
#define SECTOR_SIZE 512
#endif
/* The file I/O code operates in terms of the FILESYSTEM sector size,
which may be much larger than the underlying device's logical sector size.
So we have to use the larger of the filesystem's max, the max logical, or
the the fixed logical size.
*/
#if defined(MAX_VIRT_SECTOR_SIZE) && defined(MAX_VARIABLE_LOG_SECTOR)
#if (MAX_VIRT_SECTOR_SIZE < MAX_VARIABLE_LOG_SECTOR)
#error "MAX_VIRT_SECTOR_SIZE < MAX_VARIABLE_LOG_SECTOR"
#endif
#if (MAX_VIRT_SECTOR_SIZE % MAX_VARIABLE_LOG_SECTOR)
#error "MAX_VIRT_SECTOR_SIZE is not a multiple of MAX_VARIABLE_LOG_SECTOR"
#endif
#endif
#if !defined(DC_CACHE_BUFSIZE) && defined(MAX_VIRT_SECTOR_SIZE)
#define DC_CACHE_BUFSIZE MAX_VIRT_SECTOR_SIZE
#endif
#if !defined(DC_CACHE_BUFSIZE) && defined(MAX_VARIABLE_LOG_SECTOR)
#define DC_CACHE_BUFSIZE MAX_VARIABLE_LOG_SECTOR
#endif
#if !defined(DC_CACHE_BUFSIZE)
#define DC_CACHE_BUFSIZE SECTOR_SIZE
#endif
#endif /* FS_DEFINES_H */
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