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rockbox/firmware/common/dircache.c
Fred Bauer a71e87f132 Update some missed pointers when moving the dircache allocation 
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@31028 a1c6a512-1295-4272-9138-f99709370657
2011-11-19 14:57:56 +00:00

1638 lines
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/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2005 by Miika Pekkarinen
*
* 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.
*
****************************************************************************/
/* TODO:
- Allow cache live updating while transparent rebuild is running.
*/
#include "config.h"
#include <stdio.h>
#include <errno.h>
#include "string-extra.h"
#include <stdbool.h>
#include <stdlib.h>
#include "debug.h"
#include "system.h"
#include "logf.h"
#include "dircache.h"
#include "thread.h"
#include "kernel.h"
#include "usb.h"
#include "file.h"
#include "core_alloc.h"
#include "dir.h"
#include "storage.h"
#include "audio.h"
#if CONFIG_RTC
#include "time.h"
#include "timefuncs.h"
#endif
#include "rbpaths.h"
/* Queue commands. */
#define DIRCACHE_BUILD 1
#define DIRCACHE_STOP 2
#if (MEMORYSIZE > 8)
#define MAX_OPEN_DIRS 12
#else
#define MAX_OPEN_DIRS 8
#endif
static DIR_CACHED opendirs[MAX_OPEN_DIRS];
static char opendir_dnames[MAX_OPEN_DIRS][MAX_PATH];
#define MAX_PENDING_BINDINGS 2
struct fdbind_queue {
char path[MAX_PATH];
int fd;
};
/* Unions with char to make pointer arithmetic simpler and avoid casting */
struct dircache_entry {
struct dirinfo info;
union {
struct dircache_entry *next;
char* next_char;
};
union {
struct dircache_entry *up;
char* up_char;
};
union {
struct dircache_entry *down;
char* down_char;
};
long startcluster;
char *d_name;
};
/* Cache Layout:
*
* x - array of struct dircache_entry
* r - reserved buffer
* d - name buffer for the d_name entry of the struct dircache_entry
* |xxxxxx|rrrrrrrrr|dddddd|
*
* subsequent x are allocated from the front, d are allocated from the back,
* using the reserve buffer for entries added after initial scan
*
* after a while the cache may look like:
* |xxxxxxxx|rrrrr|dddddddd|
*
* after a reboot, the reserve buffer is restored in it's size, so that the
* total allocation size grows
* |xxxxxxxx|rrrrrrrrr|dddddddd|
*/
/* this points to the beginnging of the buffer and the first entry */
static struct dircache_entry *dircache_root;
/* these point to the start and end of the name buffer (d above) */
static char *d_names_start, *d_names_end;
/* put "." and ".." into the d_names buffer to enable easy pointer logic */
static char *dot, *dotdot;
#ifdef HAVE_MULTIVOLUME
static struct dircache_entry *append_position;
#endif
static DIR_CACHED opendirs[MAX_OPEN_DIRS];
static struct dircache_entry *fd_bindings[MAX_OPEN_FILES];
static bool dircache_initialized = false;
static bool dircache_initializing = false;
static bool thread_enabled = false;
static unsigned long allocated_size = 0;
static unsigned long dircache_size = 0;
static unsigned long entry_count = 0;
static unsigned long reserve_used = 0;
static unsigned int cache_build_ticks = 0;
static unsigned long appflags = 0;
static struct event_queue dircache_queue SHAREDBSS_ATTR;
static long dircache_stack[(DEFAULT_STACK_SIZE + 0x400)/sizeof(long)];
static const char dircache_thread_name[] = "dircache";
static struct fdbind_queue fdbind_cache[MAX_PENDING_BINDINGS];
static int fdbind_idx = 0;
/* --- Internal cache structure control functions --- */
static inline struct dircache_entry* get_entry(int id)
{
return &dircache_root[id];
}
/* flag to make sure buffer doesn't move due to other allocs.
* this is set to true completely during dircache build */
static bool dont_move = false;
static int dircache_handle;
static int move_callback(int handle, void* current, void* new)
{
(void)handle;
if (dont_move)
return BUFLIB_CB_CANNOT_MOVE;
#define UPDATE(x) if (x) { x = PTR_ADD(x, diff); }
/* relocate the cache */
ptrdiff_t diff = new - current;
for(unsigned i = 0; i < entry_count; i++)
{
UPDATE(dircache_root[i].d_name);
UPDATE(dircache_root[i].next_char);
UPDATE(dircache_root[i].up_char);
UPDATE(dircache_root[i].down_char);
}
dircache_root = new;
UPDATE(d_names_start);
UPDATE(d_names_end);
UPDATE(dot);
UPDATE(dotdot);
for(unsigned i = 0; i < MAX_OPEN_FILES; i++)
UPDATE(fd_bindings[i]);
#ifdef HAVE_MULTIVOLUME
UPDATE(append_position);
#endif
return BUFLIB_CB_OK;
}
static struct buflib_callbacks ops = {
.move_callback = move_callback,
.shrink_callback = NULL,
};
#ifdef HAVE_EEPROM_SETTINGS
/**
* Open the dircache file to save a snapshot on disk
*/
static int open_dircache_file(unsigned flags, int permissions)
{
if (permissions != 0)
return open(DIRCACHE_FILE, flags, permissions);
return open(DIRCACHE_FILE, flags);
}
/**
* Remove the snapshot file
*/
static int remove_dircache_file(void)
{
return remove(DIRCACHE_FILE);
}
#endif
/**
* Internal function to allocate a new dircache_entry from memory.
*/
static struct dircache_entry* allocate_entry(void)
{
struct dircache_entry *next_entry;
if (dircache_size > allocated_size - MAX_PATH*2)
{
logf("size limit reached");
return NULL;
}
next_entry = &dircache_root[entry_count++];
next_entry->d_name = NULL;
next_entry->up = NULL;
next_entry->down = NULL;
next_entry->next = NULL;
dircache_size += sizeof(struct dircache_entry);
return next_entry;
}
/**
* Internal function to allocate a dircache_entry and set
* ->next entry pointers.
*/
static struct dircache_entry* dircache_gen_next(struct dircache_entry *ce)
{
struct dircache_entry *next_entry;
if ( (next_entry = allocate_entry()) == NULL)
return NULL;
next_entry->up = ce->up;
ce->next = next_entry;
return next_entry;
}
/*
* Internal function to allocate a dircache_entry and set
* ->down entry pointers.
*/
static struct dircache_entry* dircache_gen_down(struct dircache_entry *ce)
{
struct dircache_entry *next_entry;
if ( (next_entry = allocate_entry()) == NULL)
return NULL;
next_entry->up = ce;
ce->down = next_entry;
return next_entry;
}
/**
* Returns true if there is an event waiting in the queue
* that requires the current operation to be aborted.
*/
static bool check_event_queue(void)
{
struct queue_event ev;
if(!queue_peek(&dircache_queue, &ev))
return false;
switch (ev.id)
{
case DIRCACHE_STOP:
case SYS_USB_CONNECTED:
#ifdef HAVE_HOTSWAP
case SYS_FS_CHANGED:
#endif
return true;
}
return false;
}
#if (CONFIG_PLATFORM & PLATFORM_NATIVE)
/* scan and build static data (avoid redundancy on stack) */
static struct
{
#ifdef HAVE_MULTIVOLUME
int volume;
#endif
struct fat_dir *dir;
struct fat_direntry *direntry;
}sab;
static int sab_process_dir(unsigned long startcluster, struct dircache_entry *ce)
{
/* normally, opendir expects a full fat_dir as parent but in our case,
* it's completely useless because we don't modify anything
* WARNING: this heavily relies on current FAT implementation ! */
/* those field are necessary to update the FAT entry in case of modification
here we don't touch anything so we put dummy values */
sab.dir->entry = 0;
sab.dir->entrycount = 0;
sab.dir->file.firstcluster = 0;
/* open directory */
int rc = fat_opendir(IF_MV2(sab.volume,) sab.dir, startcluster, sab.dir);
if(rc < 0)
{
logf("fat_opendir failed: %d", rc);
return rc;
}
/* first pass : read dir */
struct dircache_entry *first_ce = ce;
/* read through directory */
while((rc = fat_getnext(sab.dir, sab.direntry)) >= 0 && sab.direntry->name[0])
{
if(!strcmp(".", sab.direntry->name) ||
!strcmp("..", sab.direntry->name))
continue;
size_t size = strlen(sab.direntry->name) + 1;
ce->d_name = (d_names_start -= size);
ce->startcluster = sab.direntry->firstcluster;
ce->info.size = sab.direntry->filesize;
ce->info.attribute = sab.direntry->attr;
ce->info.wrtdate = sab.direntry->wrtdate;
ce->info.wrttime = sab.direntry->wrttime;
strcpy(ce->d_name, sab.direntry->name);
dircache_size += size;
if(ce->info.attribute & FAT_ATTR_DIRECTORY)
dircache_gen_down(ce);
ce = dircache_gen_next(ce);
if(ce == NULL)
return -5;
/* When simulator is used, it's only safe to yield here. */
if(thread_enabled)
{
/* Stop if we got an external signal. */
if(check_event_queue())
return -6;
yield();
}
}
/* add "." and ".." */
ce->d_name = dot;
ce->info.attribute = FAT_ATTR_DIRECTORY;
ce->startcluster = startcluster;
ce->info.size = 0;
ce->down = first_ce;
ce = dircache_gen_next(ce);
ce->d_name = dotdot;
ce->info.attribute = FAT_ATTR_DIRECTORY;
ce->startcluster = (first_ce->up ? first_ce->up->startcluster : 0);
ce->info.size = 0;
ce->down = first_ce->up;
/* second pass: recurse ! */
ce = first_ce;
while(rc >= 0 && ce)
{
if(ce->d_name != NULL && ce->down != NULL && strcmp(ce->d_name, ".")
&& strcmp(ce->d_name, ".."))
rc = sab_process_dir(ce->startcluster, ce->down);
ce = ce->next;
}
return rc;
}
/* used during the generation */
static struct fat_dir sab_fat_dir;
static int dircache_scan_and_build(IF_MV2(int volume,) struct dircache_entry *ce)
{
memset(ce, 0, sizeof(struct dircache_entry));
#ifdef HAVE_MULTIVOLUME
if (volume > 0)
{
/* broken for 100+ volumes because the format string is too small
* and we use that for size calculation */
const size_t max_len = VOL_ENUM_POS + 3;
ce->d_name = (d_names_start -= max_len);
snprintf(ce->d_name, max_len, VOL_NAMES, volume);
dircache_size += max_len;
ce->info.attribute = FAT_ATTR_DIRECTORY | FAT_ATTR_VOLUME;
ce->info.size = 0;
append_position = dircache_gen_next(ce);
ce = dircache_gen_down(ce);
}
#endif
struct fat_direntry direntry; /* ditto */
#ifdef HAVE_MULTIVOLUME
sab.volume = volume;
#endif
sab.dir = &sab_fat_dir;
sab.direntry = &direntry;
return sab_process_dir(0, ce);
}
#elif (CONFIG_PLATFORM & PLATFORM_HOSTED) /* PLATFORM_HOSTED */
static char sab_path[MAX_PATH];
static int sab_process_dir(struct dircache_entry *ce)
{
struct dirent_uncached *entry;
struct dircache_entry *first_ce = ce;
DIR_UNCACHED *dir = opendir_uncached(sab_path);
if(dir == NULL)
{
logf("Failed to opendir_uncached(%s)", sab_path);
return -1;
}
while((entry = readdir_uncached(dir)))
{
if(!strcmp(".", entry->d_name) ||
!strcmp("..", entry->d_name))
continue;
size_t size = strlen(entry->d_name) + 1;
ce->d_name = (d_names_start -= size);
ce->info = entry->info;
strcpy(ce->d_name, entry->d_name);
dircache_size += size;
if(entry->info.attribute & ATTR_DIRECTORY)
{
dircache_gen_down(ce);
if(ce->down == NULL)
{
closedir_uncached(dir);
return -1;
}
/* save current paths size */
int pathpos = strlen(sab_path);
/* append entry */
strlcpy(&sab_path[pathpos], "/", sizeof(sab_path) - pathpos);
strlcpy(&sab_path[pathpos+1], entry->d_name, sizeof(sab_path) - pathpos - 1);
int rc = sab_process_dir(ce->down);
/* restore path */
sab_path[pathpos] = '\0';
if(rc < 0)
{
closedir_uncached(dir);
return rc;
}
}
ce = dircache_gen_next(ce);
if(ce == NULL)
return -5;
/* When simulator is used, it's only safe to yield here. */
if(thread_enabled)
{
/* Stop if we got an external signal. */
if(check_event_queue())
return -1;
yield();
}
}
/* add "." and ".." */
ce->d_name = dot;
ce->info.attribute = ATTR_DIRECTORY;
ce->info.size = 0;
ce->down = first_ce;
ce = dircache_gen_next(ce);
ce->d_name = dotdot;
ce->info.attribute = ATTR_DIRECTORY;
ce->info.size = 0;
ce->down = first_ce->up;
closedir_uncached(dir);
return 0;
}
static int dircache_scan_and_build(IF_MV2(int volume,) struct dircache_entry *ce)
{
#ifdef HAVE_MULTIVOLUME
(void) volume;
#endif
memset(ce, 0, sizeof(struct dircache_entry));
strlcpy(sab_path, "/", sizeof sab_path);
return sab_process_dir(ce);
}
#endif /* PLATFORM_NATIVE */
/**
* Internal function to get a pointer to dircache_entry for a given filename.
* path: Absolute path to a file or directory (see comment)
* go_down: Returns the first entry of the directory given by the path (see comment)
*
* As a a special case, accept path="" as an alias for "/".
* Also if the path omits the first '/', it will be accepted.
*
* * If get_down=true:
* If path="/", the returned entry is the first of root directory (ie dircache_root)
* Otherwise, if 'entry' is the returned value when get_down=false,
* the functions returns entry->down (which can be NULL)
*
* * If get_down=false:
* If path="/chunk_1/chunk_2/.../chunk_n" then this functions returns the entry
* root_entry()->chunk_1->chunk_2->...->chunk_(n-1)
* Which means that
* dircache_get_entry(path)->d_name == chunk_n
*
* If path="/", the returned entry is NULL.
* If the entry doesn't exist, return NULL
*
* NOTE: this functions silently handles double '/'
*/
static struct dircache_entry* dircache_get_entry(const char *path, bool go_down)
{
char namecopy[MAX_PATH];
char* part;
char* end;
bool at_root = true;
struct dircache_entry *cache_entry = dircache_root;
strlcpy(namecopy, path, sizeof(namecopy));
for(part = strtok_r(namecopy, "/", &end); part; part = strtok_r(NULL, "/", &end))
{
/* If request another chunk, the current entry has to be directory
* and so cache_entry->down has to be non-NULL/
* Special case of root because it's already the first entry of the root directory
*
* NOTE: this is safe even if cache_entry->down is NULL */
if(!at_root)
cache_entry = cache_entry->down;
else
at_root = false;
/* scan dir for name */
while(cache_entry != NULL)
{
/* skip unused entries */
if(cache_entry->d_name == NULL)
{
cache_entry = cache_entry->next;
continue;
}
/* compare names */
if(!strcasecmp(part, cache_entry->d_name))
break;
/* go to next entry */
cache_entry = cache_entry->next;
}
/* handle not found case */
if(cache_entry == NULL)
return NULL;
}
/* NOTE: here cache_entry!=NULL so taking ->down is safe */
if(go_down)
return at_root ? cache_entry : cache_entry->down;
else
return at_root ? NULL : cache_entry;
}
#ifdef HAVE_EEPROM_SETTINGS
#define DIRCACHE_MAGIC 0x00d0c0a1
struct dircache_maindata {
long magic;
long size;
long entry_count;
long appflags;
struct dircache_entry *root_entry;
char *d_names_start;
};
/**
* Function to load the internal cache structure from disk to initialize
* the dircache really fast and little disk access.
*/
int dircache_load(void)
{
struct dircache_maindata maindata;
ssize_t bytes_read;
int fd;
if (dircache_initialized)
return -1;
logf("Loading directory cache");
dircache_size = 0;
fd = open_dircache_file(O_RDONLY, 0);
if (fd < 0)
return -2;
bytes_read = read(fd, &maindata, sizeof(struct dircache_maindata));
if (bytes_read != sizeof(struct dircache_maindata)
|| maindata.magic != DIRCACHE_MAGIC || maindata.size <= 0)
{
logf("Dircache file header error");
close(fd);
remove_dircache_file();
return -3;
}
allocated_size = maindata.size + DIRCACHE_RESERVE;
dircache_handle = core_alloc_ex("dircache", allocated_size, &ops);
/* block movement during upcoming I/O */
dont_move = true;
dircache_root = core_get_data(dircache_handle);
ALIGN_BUFFER(dircache_root, allocated_size, sizeof(struct dircache_entry*));
entry_count = maindata.entry_count;
appflags = maindata.appflags;
/* read the dircache file into memory,
* start with the struct dircache_entries */
ssize_t bytes_to_read = entry_count*sizeof(struct dircache_entry);
bytes_read = read(fd, dircache_root, bytes_to_read);
if (bytes_read != bytes_to_read)
{
logf("Dircache read failed #1");
return -6;
}
/* continue with the d_names. Fix up pointers to them if needed */
bytes_to_read = maindata.size - bytes_to_read;
d_names_start = (char*)dircache_root + allocated_size - bytes_to_read;
bytes_read = read(fd, d_names_start, bytes_to_read);
close(fd);
remove_dircache_file();
if (bytes_read != bytes_to_read)
{
logf("Dircache read failed #2");
return -7;
}
d_names_end = d_names_start + bytes_read;
dot = d_names_end - sizeof(".");
dotdot = dot - sizeof("..");
/* d_names are in reverse order, so the last entry points to the first string */
ptrdiff_t offset_d_names = maindata.d_names_start - d_names_start;
ptrdiff_t offset_entries = maindata.root_entry - dircache_root;
offset_entries *= sizeof(struct dircache_entry); /* make it bytes */
/* offset_entries is less likely to differ, so check if it's 0 in the loop
* offset_d_names however is almost always non-zero, since dircache_save()
* creates a file which causes the reserve buffer to be used. since
* we allocate a new, empty DIRCACHE_RESERVE here, the strings are
* farther behind */
if (offset_entries != 0 || offset_d_names != 0)
{
for(unsigned i = 0; i < entry_count; i++)
{
if (dircache_root[i].d_name)
dircache_root[i].d_name -= offset_d_names;
if (offset_entries == 0)
continue;
if (dircache_root[i].next_char)
dircache_root[i].next_char -= offset_entries;
if (dircache_root[i].up_char)
dircache_root[i].up_char -= offset_entries;
if (dircache_root[i].down_char)
dircache_root[i].down_char -= offset_entries;
}
}
/* Cache successfully loaded. */
dircache_size = maindata.size;
reserve_used = 0;
logf("Done, %ld KiB used", dircache_size / 1024);
dircache_initialized = true;
memset(fd_bindings, 0, sizeof(fd_bindings));
dont_move = false;
return 0;
}
/**
* Function to save the internal cache stucture to disk for fast loading
* on boot.
*/
int dircache_save(void)
{
struct dircache_maindata maindata;
int fd;
unsigned long bytes_written;
remove_dircache_file();
if (!dircache_initialized)
return -1;
logf("Saving directory cache");
dont_move = true;
fd = open_dircache_file(O_WRONLY | O_CREAT | O_TRUNC, 0666);
maindata.magic = DIRCACHE_MAGIC;
maindata.size = dircache_size;
maindata.root_entry = dircache_root;
maindata.d_names_start = d_names_start;
maindata.entry_count = entry_count;
maindata.appflags = appflags;
/* Save the info structure */
bytes_written = write(fd, &maindata, sizeof(struct dircache_maindata));
if (bytes_written != sizeof(struct dircache_maindata))
{
close(fd);
logf("dircache: write failed #1");
return -2;
}
/* Dump whole directory cache to disk
* start by writing the dircache_entries */
size_t bytes_to_write = entry_count*sizeof(struct dircache_entry);
bytes_written = write(fd, dircache_root, bytes_to_write);
if (bytes_written != bytes_to_write)
{
logf("dircache: write failed #2");
return -3;
}
/* continue with the d_names */
bytes_to_write = d_names_end - d_names_start;
bytes_written = write(fd, d_names_start, bytes_to_write);
close(fd);
if (bytes_written != bytes_to_write)
{
logf("dircache: write failed #3");
return -4;
}
dont_move = false;
return 0;
}
#endif /* HAVE_EEPROM_SETTINGS */
/**
* Internal function which scans the disk and creates the dircache structure.
*/
static int dircache_do_rebuild(void)
{
struct dircache_entry* root_entry;
unsigned int start_tick;
int i;
/* Measure how long it takes build the cache. */
start_tick = current_tick;
dircache_initializing = true;
appflags = 0;
/* reset dircache and alloc root entry */
entry_count = 0;
root_entry = allocate_entry();
dont_move = true;
#ifdef HAVE_MULTIVOLUME
append_position = root_entry;
for (i = NUM_VOLUMES; i >= 0; i--)
{
if (fat_ismounted(i))
{
#endif
cpu_boost(true);
#ifdef HAVE_MULTIVOLUME
if (dircache_scan_and_build(IF_MV2(i,) append_position) < 0)
#else
if (dircache_scan_and_build(IF_MV2(0,) root_entry) < 0)
#endif /* HAVE_MULTIVOLUME */
{
logf("dircache_scan_and_build failed");
cpu_boost(false);
dircache_size = 0;
dircache_initializing = false;
dont_move = false;
return -2;
}
cpu_boost(false);
#ifdef HAVE_MULTIVOLUME
}
}
#endif
logf("Done, %ld KiB used", dircache_size / 1024);
dircache_initialized = true;
dircache_initializing = false;
cache_build_ticks = current_tick - start_tick;
/* Initialized fd bindings. */
memset(fd_bindings, 0, sizeof(fd_bindings));
for (i = 0; i < fdbind_idx; i++)
dircache_bind(fdbind_cache[i].fd, fdbind_cache[i].path);
fdbind_idx = 0;
if (thread_enabled)
{
if (allocated_size - dircache_size < DIRCACHE_RESERVE)
reserve_used = DIRCACHE_RESERVE - (allocated_size - dircache_size);
}
dont_move = false;
return 1;
}
/*
* Free all associated resources, if any */
static void dircache_free(void)
{
if (dircache_handle > 0)
dircache_handle = core_free(dircache_handle);
dircache_size = allocated_size = 0;
}
/**
* Internal thread that controls transparent cache building.
*/
static void dircache_thread(void)
{
struct queue_event ev;
while (1)
{
queue_wait(&dircache_queue, &ev);
switch (ev.id)
{
#ifdef HAVE_HOTSWAP
case SYS_FS_CHANGED:
if (!dircache_initialized)
break;
dircache_initialized = false;
#endif
case DIRCACHE_BUILD:
thread_enabled = true;
if (dircache_do_rebuild() < 0)
dircache_free();
thread_enabled = false;
break ;
case DIRCACHE_STOP:
logf("Stopped the rebuilding.");
dircache_initialized = false;
break ;
case SYS_USB_CONNECTED:
usb_acknowledge(SYS_USB_CONNECTED_ACK);
usb_wait_for_disconnect(&dircache_queue);
break ;
}
}
}
static void generate_dot_d_names(void)
{
dot = (d_names_start -= sizeof("."));
dotdot = (d_names_start -= sizeof(".."));
dircache_size += sizeof(".") + sizeof("..");
strcpy(dot, ".");
strcpy(dotdot, "..");
}
/**
* Start scanning the disk to build the dircache.
* Either transparent or non-transparent build method is used.
*/
int dircache_build(int last_size)
{
if (dircache_initialized || thread_enabled)
return -3;
logf("Building directory cache");
#ifdef HAVE_EEPROM_SETTINGS
remove_dircache_file();
#endif
/* Background build, dircache has been previously allocated and */
if (allocated_size > MAX(last_size, 0))
{
d_names_start = d_names_end;
dircache_size = 0;
reserve_used = 0;
thread_enabled = true;
dircache_initializing = true;
generate_dot_d_names();
queue_post(&dircache_queue, DIRCACHE_BUILD, 0);
return 2;
}
/* start by freeing, as we possibly re-allocate */
dircache_free();
if (last_size > DIRCACHE_RESERVE && last_size < DIRCACHE_LIMIT )
{
allocated_size = last_size + DIRCACHE_RESERVE;
dircache_handle = core_alloc_ex("dircache", allocated_size, &ops);
dircache_root = core_get_data(dircache_handle);
ALIGN_BUFFER(dircache_root, allocated_size, sizeof(struct dircache_entry*));
d_names_start = d_names_end = ((char*)dircache_root)+allocated_size-1;
dircache_size = 0;
thread_enabled = true;
generate_dot_d_names();
/* Start a transparent rebuild. */
queue_post(&dircache_queue, DIRCACHE_BUILD, 0);
return 3;
}
/* We'll use the entire audiobuf to allocate the dircache
* struct dircache_entrys are allocated from the beginning
* and their corresponding d_name from the end
* after generation the buffer will be compacted with DIRCACHE_RESERVE
* free bytes inbetween */
size_t available = audio_buffer_available();
/* try to allocate at least 1MB, the more the better */
if (available < 1<<20) available = 1<<20;
if (available > DIRCACHE_LIMIT) available = DIRCACHE_LIMIT;
dircache_handle = core_alloc_ex("dircache", available, &ops);
if (dircache_handle <= 0)
return -1; /* that was not successful, should try rebooting */
char* buf = core_get_data(dircache_handle);
dircache_root = (struct dircache_entry*)ALIGN_UP(buf,
sizeof(struct dircache_entry*));
d_names_start = d_names_end = buf + available - 1;
dircache_size = 0;
generate_dot_d_names();
/* Start a non-transparent rebuild. */
int res = dircache_do_rebuild();
if (res < 0)
goto fail;
/* now compact the dircache buffer */
char* dst = ((char*)&dircache_root[entry_count] + DIRCACHE_RESERVE);
ptrdiff_t offset = d_names_start - dst;
if (offset <= 0) /* something went wrong */
{
res = -1;
goto fail;
}
/* memmove d_names down, there's a possibility of overlap
* equivaent to dircache_size - entry_count*sizeof(struct dircache_entry) */
ptrdiff_t size_to_move = d_names_end - d_names_start;
memmove(dst, d_names_start, size_to_move);
/* fix up pointers to the d_names */
for(unsigned i = 0; i < entry_count; i++)
dircache_root[i].d_name -= offset;
d_names_start -= offset;
d_names_end -= offset;
dot -= offset;
dotdot -= offset;
/* equivalent to dircache_size + DIRCACHE_RESERVE + align */
allocated_size = (d_names_end - buf);
reserve_used = 0;
core_shrink(dircache_handle, dircache_root, allocated_size);
return res;
fail:
dircache_disable();
return res;
}
/**
* Main initialization function that must be called before any other
* operations within the dircache.
*/
void dircache_init(void)
{
int i;
int thread_id __attribute__((unused));
dircache_initialized = false;
dircache_initializing = false;
memset(opendirs, 0, sizeof(opendirs));
for (i = 0; i < MAX_OPEN_DIRS; i++)
{
opendirs[i].theent.d_name = opendir_dnames[i];
}
queue_init(&dircache_queue, true);
thread_id = create_thread(dircache_thread, dircache_stack,
sizeof(dircache_stack), 0, dircache_thread_name
IF_PRIO(, PRIORITY_BACKGROUND)
IF_COP(, CPU));
#ifdef HAVE_IO_PRIORITY
thread_set_io_priority(thread_id,IO_PRIORITY_BACKGROUND);
#endif
}
/**
* Returns true if dircache has been initialized and is ready to be used.
*/
bool dircache_is_enabled(void)
{
return dircache_initialized;
}
/**
* Returns true if dircache is being initialized.
*/
bool dircache_is_initializing(void)
{
return dircache_initializing || thread_enabled;
}
/**
* Set application flags used to determine if dircache is still intact.
*/
void dircache_set_appflag(long mask)
{
appflags |= mask;
}
/**
* Get application flags used to determine if dircache is still intact.
*/
bool dircache_get_appflag(long mask)
{
return dircache_is_enabled() && (appflags & mask);
}
/**
* Returns the current number of entries (directories and files) in the cache.
*/
int dircache_get_entry_count(void)
{
return entry_count;
}
/**
* Returns the allocated space for dircache (without reserve space).
*/
int dircache_get_cache_size(void)
{
return dircache_is_enabled() ? dircache_size : 0;
}
/**
* Returns how many bytes of the reserve allocation for live cache
* updates have been used.
*/
int dircache_get_reserve_used(void)
{
return dircache_is_enabled() ? reserve_used : 0;
}
/**
* Returns the time in kernel ticks that took to build the cache.
*/
int dircache_get_build_ticks(void)
{
return dircache_is_enabled() ? cache_build_ticks : 0;
}
/**
* Disables dircache without freeing the buffer (so it can be re-enabled
* afterwards with dircache_resume() or dircache_build()), usually
* called when accepting an usb connection */
void dircache_suspend(void)
{
int i;
bool cache_in_use;
if (thread_enabled)
queue_post(&dircache_queue, DIRCACHE_STOP, 0);
while (thread_enabled)
sleep(1);
dircache_initialized = false;
logf("Waiting for cached dirs to release");
do {
cache_in_use = false;
for (i = 0; i < MAX_OPEN_DIRS; i++) {
if (!opendirs[i].regulardir && opendirs[i].busy)
{
cache_in_use = true;
sleep(1);
break ;
}
}
} while (cache_in_use) ;
logf("Cache released");
entry_count = 0;
}
/**
* Re-enables the dircache if previous suspended by dircache_suspend
* or dircache_steal_buffer(), re-using the already allocated buffer
*
* Returns true if the background build is started, false otherwise
* (e.g. if no buffer was previously allocated)
*/
bool dircache_resume(void)
{
bool ret = allocated_size > 0;
if (ret) /* only resume if already allocated */
ret = (dircache_build(0) > 0);
return (allocated_size > 0);
}
/**
* Disables the dircache entirely. Usually called on shutdown or when
* deactivated
*/
void dircache_disable(void)
{
dircache_suspend();
dircache_free();
}
/**
* Steal the allocated dircache buffer and disable dircache.
*/
void* dircache_steal_buffer(size_t *size)
{
dircache_suspend();
if (dircache_size == 0)
{
*size = 0;
return NULL;
}
/* since we give up the buffer (without freeing), it must not move anymore */
dont_move = true;
*size = dircache_size + (DIRCACHE_RESERVE-reserve_used);
return dircache_root;
}
/**
* Usermode function to return dircache_entry index to the given path.
*/
static int dircache_get_entry_id_ex(const char *filename, bool go_down)
{
if (!dircache_initialized || filename == NULL)
return -1;
struct dircache_entry* res = dircache_get_entry(filename, go_down);
return res ? res - dircache_root : -1;
}
int dircache_get_entry_id(const char* filename)
{
return dircache_get_entry_id_ex(filename, false);
}
/**
* Internal: Get the startcluster for the index
*/
long _dircache_get_entry_startcluster(int id)
{
return get_entry(id)->startcluster;
}
/**
* Internal: Get the struct dirinfo for the index
*/
struct dirinfo* _dircache_get_entry_dirinfo(int id)
{
return &get_entry(id)->info;
}
/*
* build a path from an entry upto the root using recursion
*
* it appends '/' after strlcat, therefore buf[0] needs to be prepared with '/'
* and it will leave a trailing '/'
*
* returns the position of that trailing '/' so it can be deleted afterwards
* (or, in case of truncation, the position of the nul byte */
static size_t copy_path_helper(const struct dircache_entry *entry, char *buf, size_t size)
{
int offset = 1;
/* has parent? */
if (entry->up)
offset += copy_path_helper(entry->up, buf, size);
size_t len = strlcpy(buf+offset, entry->d_name, size - offset) + offset;
if (len < size)
{
buf[len++] = '/';
buf[len] = '\0';
}
return len-1;
}
/**
* Function to copy the full absolute path from dircache to the given buffer
* using the given dircache_entry pointer.
*
* Returns the size of the resulting string, or 0 if an error occured
*/
size_t dircache_copy_path(int index, char *buf, size_t size)
{
if (!size || !buf || index < 0)
return 0;
buf[0] = '/';
size_t res = copy_path_helper(&dircache_root[index], buf, size - 1);
/* fixup trailing '/' */
buf[res] = '\0';
return res;
}
/* --- Directory cache live updating functions --- */
static int block_until_ready(void)
{
/* Block until dircache has been built. */
while (!dircache_initialized && dircache_is_initializing())
sleep(1);
if (!dircache_initialized)
return -1;
return 0;
}
static struct dircache_entry* dircache_new_entry(const char *path, int attribute)
{
struct dircache_entry *entry;
char basedir[MAX_PATH*2];
char *new;
long last_cache_size = dircache_size;
strlcpy(basedir, path, sizeof(basedir));
new = strrchr(basedir, '/');
if (new == NULL)
{
logf("error occurred");
dircache_initialized = false;
return NULL;
}
*new = '\0';
new++;
entry = dircache_get_entry(basedir, true);
if (entry == NULL)
{
logf("basedir not found!");
logf("%s", basedir);
dircache_initialized = false;
return NULL;
}
if (reserve_used + 2*sizeof(struct dircache_entry) + strlen(new)+1
>= DIRCACHE_RESERVE)
{
logf("not enough space");
dircache_initialized = false;
return NULL;
}
while (entry->next != NULL)
entry = entry->next;
if (entry->d_name != NULL)
{
entry = dircache_gen_next(entry);
if (entry == NULL)
{
dircache_initialized = false;
return NULL;
}
}
size_t size = strlen(new) + 1;
entry->d_name = (d_names_start -= size);
entry->startcluster = 0;
memset(&entry->info, 0, sizeof(entry->info));
entry->info.attribute = attribute;
strcpy(entry->d_name, new);
dircache_size += size;
if (attribute & ATTR_DIRECTORY)
{
logf("gen_down");
dircache_gen_down(entry);
}
reserve_used += dircache_size - last_cache_size;
return entry;
}
void dircache_bind(int fd, const char *path)
{
struct dircache_entry *entry;
/* Queue requests until dircache has been built. */
if (!dircache_initialized && dircache_is_initializing())
{
if (fdbind_idx >= MAX_PENDING_BINDINGS)
return ;
strlcpy(fdbind_cache[fdbind_idx].path, path,
sizeof(fdbind_cache[fdbind_idx].path));
fdbind_cache[fdbind_idx].fd = fd;
fdbind_idx++;
return ;
}
if (!dircache_initialized)
return ;
logf("bind: %d/%s", fd, path);
entry = dircache_get_entry(path, false);
if (entry == NULL)
{
logf("not found!");
dircache_initialized = false;
return ;
}
fd_bindings[fd] = entry;
}
void dircache_update_filesize(int fd, long newsize, long startcluster)
{
if (!dircache_initialized || fd < 0)
return ;
if (fd_bindings[fd] == NULL)
{
logf("dircache fd(%d) access error", fd);
dircache_initialized = false;
return ;
}
fd_bindings[fd]->info.size = newsize;
fd_bindings[fd]->startcluster = startcluster;
}
void dircache_update_filetime(int fd)
{
#if CONFIG_RTC == 0
(void)fd;
#else
short year;
struct tm *now = get_time();
if (!dircache_initialized || fd < 0)
return ;
if (fd_bindings[fd] == NULL)
{
logf("dircache fd access error");
dircache_initialized = false;
return ;
}
year = now->tm_year+1900-1980;
fd_bindings[fd]->info.wrtdate = (((year)&0x7f)<<9) |
(((now->tm_mon+1)&0xf)<<5) |
(((now->tm_mday)&0x1f));
fd_bindings[fd]->info.wrttime = (((now->tm_hour)&0x1f)<<11) |
(((now->tm_min)&0x3f)<<5) |
(((now->tm_sec/2)&0x1f));
#endif
}
void dircache_mkdir(const char *path)
{ /* Test ok. */
if (block_until_ready())
return ;
logf("mkdir: %s", path);
dircache_new_entry(path, ATTR_DIRECTORY);
}
void dircache_rmdir(const char *path)
{ /* Test ok. */
struct dircache_entry *entry;
if (block_until_ready())
return ;
logf("rmdir: %s", path);
entry = dircache_get_entry(path, false);
if (entry == NULL || entry->down == NULL)
{
logf("not found or not a directory!");
dircache_initialized = false;
return ;
}
entry->down = NULL;
entry->d_name = NULL;
}
/* Remove a file from cache */
void dircache_remove(const char *name)
{ /* Test ok. */
struct dircache_entry *entry;
if (block_until_ready())
return ;
logf("remove: %s", name);
entry = dircache_get_entry(name, false);
if (entry == NULL)
{
logf("not found!");
dircache_initialized = false;
return ;
}
entry->d_name = NULL;
}
void dircache_rename(const char *oldpath, const char *newpath)
{ /* Test ok. */
struct dircache_entry *entry, *newentry;
struct dircache_entry oldentry;
char absolute_path[MAX_PATH*2];
char *p;
if (block_until_ready())
return ;
logf("rename: %s->%s", oldpath, newpath);
entry = dircache_get_entry(oldpath, false);
if (entry == NULL)
{
logf("not found!");
dircache_initialized = false;
return ;
}
/* Delete the old entry. */
entry->d_name = NULL;
/** If we rename the same filename twice in a row, we need to
* save the data, because the entry will be re-used. */
oldentry = *entry;
/* Generate the absolute path for destination if necessary. */
if (newpath[0] != '/')
{
strlcpy(absolute_path, oldpath, sizeof(absolute_path));
p = strrchr(absolute_path, '/');
if (!p)
{
logf("Invalid path");
dircache_initialized = false;
return ;
}
*p = '\0';
strlcpy(p, absolute_path, sizeof(absolute_path)-strlen(p));
newpath = absolute_path;
}
newentry = dircache_new_entry(newpath, entry->info.attribute);
if (newentry == NULL)
{
dircache_initialized = false;
return ;
}
newentry->down = oldentry.down;
newentry->startcluster = oldentry.startcluster;
newentry->info.size = oldentry.info.size;
newentry->info.wrtdate = oldentry.info.wrtdate;
newentry->info.wrttime = oldentry.info.wrttime;
}
void dircache_add_file(const char *path, long startcluster)
{
struct dircache_entry *entry;
if (block_until_ready())
return ;
logf("add file: %s", path);
entry = dircache_new_entry(path, 0);
if (entry == NULL)
return ;
entry->startcluster = startcluster;
}
static bool is_disable_msg_pending(void)
{
return check_event_queue();
}
DIR_CACHED* opendir_cached(const char* name)
{
int dd;
DIR_CACHED* pdir = opendirs;
if ( name[0] != '/' )
{
DEBUGF("Only absolute paths supported right now\n");
return NULL;
}
/* find a free dir descriptor */
for ( dd=0; dd<MAX_OPEN_DIRS; dd++, pdir++)
if ( !pdir->busy )
break;
if ( dd == MAX_OPEN_DIRS )
{
DEBUGF("Too many dirs open\n");
errno = EMFILE;
return NULL;
}
pdir->busy = true;
if (!dircache_initialized || is_disable_msg_pending())
{
pdir->internal_entry = -1;
pdir->regulardir = opendir_uncached(name);
}
else
{
pdir->regulardir = NULL;
pdir->internal_entry = dircache_get_entry_id_ex(name, true);
pdir->theent.info.attribute = -1; /* used to make readdir_cached aware of the first call */
}
if (pdir->internal_entry == -1 && pdir->regulardir == NULL)
{
pdir->busy = false;
return NULL;
}
return pdir;
}
struct dirent_cached* readdir_cached(DIR_CACHED* dir)
{
struct dircache_entry *ce = get_entry(dir->internal_entry);
struct dirent_uncached *regentry;
if (!dir->busy)
return NULL;
if (dir->regulardir != NULL)
{
regentry = readdir_uncached(dir->regulardir);
if (regentry == NULL)
return NULL;
strlcpy(dir->theent.d_name, regentry->d_name, MAX_PATH);
dir->theent.startcluster = regentry->startcluster;
dir->theent.info = regentry->info;
return &dir->theent;
}
/* if theent.attribute=-1 then this is the first call */
/* otherwise, this is is not so we first take the entry's ->next */
/* NOTE: normal file can't have attribute=-1 */
if(dir->theent.info.attribute != -1)
ce = ce->next;
/* skip unused entries */
while(ce != NULL && ce->d_name == NULL)
ce = ce->next;
if (ce == NULL)
return NULL;
strlcpy(dir->theent.d_name, ce->d_name, MAX_PATH);
/* Can't do `dir->theent = *ce`
because that modifies the d_name pointer. */
dir->theent.startcluster = ce->startcluster;
dir->theent.info = ce->info;
dir->internal_entry = ce - dircache_root;
//logf("-> %s", ce->d_name);
return &dir->theent;
}
int closedir_cached(DIR_CACHED* dir)
{
if (!dir->busy)
return -1;
dir->busy=false;
if (dir->regulardir != NULL)
return closedir_uncached(dir->regulardir);
return 0;
}
int mkdir_cached(const char *name)
{
int rc=mkdir_uncached(name);
if (rc >= 0)
dircache_mkdir(name);
return(rc);
}
int rmdir_cached(const char* name)
{
int rc=rmdir_uncached(name);
if(rc >= 0)
dircache_rmdir(name);
return(rc);
}
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