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|
/* ScummVM - Scumm Interpreter
* Copyright (C) 2005-2006 The ScummVM project
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* $URL$
* $Id$
*
*/
#include "backends/ps2/fileio.h"
#include <tamtypes.h>
#include <kernel.h>
#include <fileio.h>
#include <assert.h>
#include <string.h>
#include <cdvd_rpc.h>
#include "backends/ps2/asyncfio.h"
#include "base/engine.h"
#include "common/file.h"
#define CACHE_SIZE (2048 * 32)
#define MAX_READ_STEP (2048 * 16)
#define MAX_CACHED_FILES 6
#define CACHE_READ_THRESHOLD (16 * 2048)
#define CACHE_FILL_MIN (2048 * 24)
#define READ_ALIGN 64 // align all reads to the size of an EE cache line
#define READ_ALIGN_MASK (READ_ALIGN - 1)
extern void sioprintf(const char *zFormat, ...);
AsyncFio fio;
Ps2File::Ps2File(int64 cacheId) {
_cacheId = cacheId;
}
Ps2File::~Ps2File(void) {
}
class Ps2ReadFile : public Ps2File {
public:
Ps2ReadFile(int64 cacheId, bool stream);
virtual ~Ps2ReadFile(void);
virtual bool open(const char *name);
virtual uint32 read(void *dest, uint32 len);
virtual uint32 write(const void *src, uint32 len);
virtual uint32 tell(void);
virtual uint32 size(void);
virtual int seek(int32 offset, int origin);
virtual bool eof(void);
private:
void cacheReadAhead(void);
void cacheReadSync(void);
int _fd, _sema;
uint8 *_cacheBuf;
bool _cacheOpRunning;
uint32 _filePos, _physFilePos, _cachePos;
uint32 _fileSize, _bytesInCache, _cacheOfs;
uint32 _readBytesBlock;
bool _stream;
};
Ps2ReadFile::Ps2ReadFile(int64 cacheId, bool stream) : Ps2File(cacheId) {
_fd = -1;
_cacheBuf = (uint8*)memalign(64, CACHE_SIZE);
_cacheOpRunning = 0;
_filePos = _physFilePos = _cachePos = 0;
_fileSize = _bytesInCache = _cacheOfs = 0;
_cacheOpRunning = false;
_readBytesBlock = 0;
_stream = stream;
ee_sema_t newSema;
newSema.init_count = 1;
newSema.max_count = 1;
_sema = CreateSema(&newSema);
assert(_sema >= 0);
}
Ps2ReadFile::~Ps2ReadFile(void) {
if (_cacheOpRunning)
cacheReadSync();
free(_cacheBuf);
if (_fd >= 0)
fio.close(_fd);
DeleteSema(_sema);
}
bool Ps2ReadFile::open(const char *name) {
assert(_fd < 0);
_fd = fio.open(name, O_RDONLY);
if (_fd >= 0) {
_fileSize = fio.seek(_fd, 0, SEEK_END);
fio.seek(_fd, 0, SEEK_SET);
return true;
} else
return false;
}
uint32 Ps2ReadFile::tell(void) {
WaitSema(_sema);
uint32 res = _filePos;
SignalSema(_sema);
return res;
}
uint32 Ps2ReadFile::size(void) {
WaitSema(_sema);
uint32 res = _fileSize;
SignalSema(_sema);
return res;
}
bool Ps2ReadFile::eof(void) {
WaitSema(_sema);
bool res = (_filePos == _fileSize);
SignalSema(_sema);
return res;
}
int Ps2ReadFile::seek(int32 offset, int origin) {
WaitSema(_sema);
int seekDest;
int res = -1;
switch (origin) {
case SEEK_SET:
seekDest = offset;
break;
case SEEK_CUR:
seekDest = _filePos + offset;
break;
case SEEK_END:
seekDest = _fileSize + offset;
break;
default:
seekDest = -1;
break;
}
if ((seekDest >= 0) && (seekDest <= (int)_fileSize)) {
_filePos = seekDest;
res = 0;
}
SignalSema(_sema);
return res;
}
void Ps2ReadFile::cacheReadAhead(void) {
if (_cacheOpRunning) {
// there's already some cache read running
if (fio.poll(_fd)) // did it finish?
cacheReadSync(); // yes.
}
if ((!_cacheOpRunning) && ((_readBytesBlock >= CACHE_READ_THRESHOLD) || _stream) && fio.fioAvail()) {
// the engine seems to do sequential reads and there are no other I/Os going on. read ahead.
uint32 cachePosEnd = _cachePos + _bytesInCache;
if (_cachePos > _filePos)
return; // there was a seek in the meantime, don't cache.
if (cachePosEnd - _filePos >= CACHE_FILL_MIN)
return; // cache is full enough.
if (cachePosEnd == _fileSize)
return; // can't read beyond EOF.
assert(cachePosEnd < _fileSize);
if (_cachePos + _bytesInCache <= _filePos) {
_cacheOfs = _bytesInCache = 0;
_cachePos = cachePosEnd = _filePos & ~READ_ALIGN_MASK;
assert(_filePos == _physFilePos);
} else {
uint32 cacheDiff = _filePos - _cachePos;
assert(_bytesInCache >= cacheDiff);
cacheDiff &= ~READ_ALIGN_MASK;
_bytesInCache -= cacheDiff;
_cachePos += cacheDiff;
_cacheOfs = (_cacheOfs + cacheDiff) % CACHE_SIZE;
}
if (_physFilePos != cachePosEnd) {
sioprintf("unexpected _physFilePos %d cache %d %d", _physFilePos, _cacheOfs, _bytesInCache);
assert(!(cachePosEnd & READ_ALIGN_MASK));
_physFilePos = fio.seek(_fd, cachePosEnd, SEEK_SET);
if (_physFilePos != cachePosEnd) {
sioprintf("cache seek error: seek to %d instead of %d, fs = %d", _physFilePos, cachePosEnd, _fileSize);
return;
}
}
uint32 cacheDest = (_cacheOfs + _bytesInCache) % CACHE_SIZE;
uint32 cacheRead = CACHE_SIZE - _bytesInCache;
if (cacheDest + cacheRead > CACHE_SIZE)
cacheRead = CACHE_SIZE - cacheDest;
if (cacheRead > MAX_READ_STEP)
cacheRead = MAX_READ_STEP;
assert((!(cacheRead & READ_ALIGN_MASK)) && cacheRead);
_cacheOpRunning = true;
fio.read(_fd, _cacheBuf + cacheDest, cacheRead);
}
}
void Ps2ReadFile::cacheReadSync(void) {
if (_cacheOpRunning) {
int res = fio.sync(_fd);
assert(res >= 0);
_bytesInCache += res;
_physFilePos += res;
_cacheOpRunning = false;
}
}
uint32 Ps2ReadFile::read(void *dest, uint32 len) {
WaitSema(_sema);
uint8 *destBuf = (uint8*)dest;
if ((_filePos < _cachePos) || (_filePos + len > _cachePos + _bytesInCache))
cacheReadSync(); // we have to read from CD, sync cache.
while (len && (_filePos != _fileSize)) {
if ((_filePos >= _cachePos) && (_filePos < _cachePos + _bytesInCache)) { // read from cache
uint32 staPos = (_cacheOfs + (_filePos - _cachePos)) % CACHE_SIZE;
uint32 cpyLen = _bytesInCache - (_filePos - _cachePos);
if (cpyLen > len)
cpyLen = len;
if (staPos + cpyLen > CACHE_SIZE)
cpyLen = CACHE_SIZE - staPos;
assert(cpyLen);
memcpy(destBuf, _cacheBuf + staPos, cpyLen);
_filePos += cpyLen;
destBuf += cpyLen;
_readBytesBlock += len;
len -= cpyLen;
} else { // cache miss
assert(!_cacheOpRunning);
if (_physFilePos != _filePos) {
if ((_filePos < _physFilePos) || (_filePos > _physFilePos + (CACHE_SIZE / 2)))
_readBytesBlock = 0; // reset cache hit count
_physFilePos = _filePos & ~READ_ALIGN_MASK;
if (fio.seek(_fd, _physFilePos, SEEK_SET) != (int)_physFilePos)
break; // read beyond EOF
}
int doRead = len + (_filePos - _physFilePos);
doRead = (doRead + READ_ALIGN_MASK) & ~READ_ALIGN_MASK;
if (doRead > MAX_READ_STEP)
doRead = MAX_READ_STEP;
if (doRead < 2048)
doRead = 2048;
fio.read(_fd, _cacheBuf, doRead);
_cachePos = _physFilePos;
_cacheOfs = 0;
_bytesInCache = fio.sync(_fd);
_physFilePos += _bytesInCache;
if (!_bytesInCache)
break; // EOF
}
}
cacheReadAhead();
SignalSema(_sema);
return destBuf - (uint8*)dest;
}
uint32 Ps2ReadFile::write(const void *src, uint32 len) {
sioprintf("write request on Ps2ReadFile!");
SleepThread();
return 0;
}
class Ps2WriteFile : public Ps2File {
public:
Ps2WriteFile(int64 cacheId);
virtual ~Ps2WriteFile(void);
virtual bool open(const char *name);
virtual uint32 read(void *dest, uint32 len);
virtual uint32 write(const void *src, uint32 len);
virtual uint32 tell(void);
virtual uint32 size(void);
virtual int seek(int32 offset, int origin);
virtual bool eof(void);
private:
int _fd;
uint8 *_cacheBuf;
uint32 _filePos, _bytesInCache;
};
Ps2WriteFile::Ps2WriteFile(int64 cacheId) : Ps2File(cacheId) {
_fd = -1;
_cacheBuf = (uint8*)malloc(CACHE_SIZE);
_filePos = _bytesInCache = 0;
}
Ps2WriteFile::~Ps2WriteFile(void) {
if ((_fd >= 0) && (_bytesInCache)) {
fio.write(_fd, _cacheBuf, _bytesInCache);
int wrRes = fio.sync(_fd);
if (wrRes != (int)_bytesInCache) // too late to return an error
printf("Cache flush on fclose(): Unable to write %d cached bytes to mc, only %d bytes written\n", _bytesInCache, wrRes);
}
if (_fd >= 0)
fio.close(_fd);
free(_cacheBuf);
}
bool Ps2WriteFile::open(const char *name) {
_fd = fio.open(name, O_WRONLY | O_CREAT | O_TRUNC);
return (_fd >= 0);
}
uint32 Ps2WriteFile::read(void *dest, uint32 len) {
printf("ERROR: Read request on Ps2WriteFile\n");
SleepThread();
return 0;
}
uint32 Ps2WriteFile::write(const void *src, uint32 len) {
uint32 size = len;
uint8 *srcBuf = (uint8*)src;
while (size) {
uint32 doCpy = (len > CACHE_SIZE - _bytesInCache) ? (CACHE_SIZE - _bytesInCache) : len;
if (doCpy) {
memcpy(_cacheBuf + _bytesInCache, srcBuf, doCpy);
_bytesInCache += doCpy;
srcBuf += doCpy;
size -= doCpy;
}
if (_bytesInCache == CACHE_SIZE) {
fio.write(_fd, _cacheBuf, _bytesInCache);
if (fio.sync(_fd) != (int)_bytesInCache) {
printf("Unable to flush %d cached bytes to memory card!\n", _bytesInCache);
return 0;
}
_filePos += _bytesInCache;
_bytesInCache = 0;
}
}
return len;
}
uint32 Ps2WriteFile::tell(void) {
return _bytesInCache + _filePos;
}
uint32 Ps2WriteFile::size(void) {
return tell();
}
int Ps2WriteFile::seek(int32 offset, int origin) {
printf("Seek(%d/%d) request on Ps2WriteFile\n", offset, origin);
SleepThread();
return 0;
}
bool Ps2WriteFile::eof(void) {
return true;
}
struct TocNode {
char name[64];
TocNode *next, *sub;
bool isDir;
uint8 nameLen;
};
class TocManager {
public:
TocManager(void);
~TocManager(void);
void readEntries(const char *root);
int64 fileExists(const char *name);
bool haveEntries(void);
private:
void readDir(const char *path, TocNode **node, int level);
TocNode *_rootNode;
char _root[256];
uint8 _rootLen;
};
TocManager tocManager;
struct FioHandleCache {
Ps2File *file;
FioHandleCache *next, *prev;
};
static FioHandleCache *cacheListStart = NULL;
static FioHandleCache *cacheListEnd = NULL;
static int cacheListLen = 0;
static int openFileCount = 0;
static int cacheListSema = -1;
Ps2File *findInCache(int64 id);
FILE *ps2_fopen(const char *fname, const char *mode) {
if (cacheListSema == -1) {
ee_sema_t newSema;
newSema.init_count = 1;
newSema.max_count = 1;
cacheListSema = CreateSema(&newSema);
assert(cacheListSema >= 0);
}
if (!tocManager.haveEntries() && g_engine) // read the TOC the first time the engine opens a file
// FIXME: Dear porter, you probably want to use ConfMan.get("path") here to get the data path
tocManager.readEntries(g_engine->getGameDataPath());
if (((mode[0] != 'r') && (mode[0] != 'w')) || ((mode[1] != '\0') && (mode[1] != 'b'))) {
printf("unsupported mode \"%s\" for file \"%s\"\n", mode, fname);
return NULL;
}
bool rdOnly = (mode[0] == 'r');
int64 cacheId = -1;
if (rdOnly && tocManager.haveEntries())
cacheId = tocManager.fileExists(fname);
if (cacheId != 0) {
Ps2File *file = findInCache(cacheId);
if (file)
return (FILE*)file;
if (rdOnly) {
bool isAudioFile = strstr(fname, ".bun") || strstr(fname, ".BUN") || strstr(fname, ".Bun");
file = new Ps2ReadFile(cacheId, isAudioFile);
} else
file = new Ps2WriteFile(cacheId);
if (file->open(fname)) {
openFileCount++;
return (FILE*)file;
} else
delete file;
}
return NULL;
}
void checkCacheListLen(void) {
while ((cacheListLen > MAX_CACHED_FILES) || ((openFileCount > 13) && cacheListLen)) {
assert(cacheListEnd && cacheListStart);
delete cacheListEnd->file;
if (cacheListEnd->prev) {
cacheListEnd->prev->next = NULL;
FioHandleCache *temp = cacheListEnd;
cacheListEnd = cacheListEnd->prev;
delete temp;
} else {
assert(cacheListEnd == cacheListStart);
assert(cacheListLen == 1);
delete cacheListEnd;
cacheListEnd = cacheListStart = NULL;
}
cacheListLen--;
openFileCount--;
}
}
int ps2_fclose(FILE *stream) {
Ps2File *file = (Ps2File*)stream;
if (file->_cacheId > 0) { // this is a file on the CD, could be smart to cache it
FioHandleCache *newHandle = new FioHandleCache;
newHandle->file = file;
file->seek(0, SEEK_SET);
WaitSema(cacheListSema);
if (!cacheListEnd) {
assert(!cacheListStart);
newHandle->prev = newHandle->next = NULL;
cacheListEnd = cacheListStart = newHandle;
} else {
assert(cacheListStart);
newHandle->prev = NULL;
newHandle->next = cacheListStart;
cacheListStart->prev = newHandle;
cacheListStart = newHandle;
}
cacheListLen++;
checkCacheListLen();
SignalSema(cacheListSema);
} else {
openFileCount--;
delete file;
}
return 0;
}
Ps2File *findInCache(int64 id) {
if (id <= 0)
return NULL;
WaitSema(cacheListSema);
FioHandleCache *node = cacheListStart;
while (node) {
if (node->file->_cacheId == id) {
if (node == cacheListStart)
cacheListStart = node->next;
if (node == cacheListEnd)
cacheListEnd = node->prev;
if (node->prev)
node->prev->next = node->next;
if (node->next)
node->next->prev = node->prev;
Ps2File *ret = node->file;
delete node;
cacheListLen--;
SignalSema(cacheListSema);
return ret;
} else
node = node->next;
}
SignalSema(cacheListSema);
return NULL;
}
int ps2_fseek(FILE *stream, long offset, int origin) {
return ((Ps2File*)stream)->seek(offset, origin);
}
uint32 ps2_ftell(FILE *stream) {
return ((Ps2File*)stream)->tell();
}
uint32 ps2_fsize(FILE *stream) {
return ((Ps2File*)stream)->size();
}
int ps2_feof(FILE *stream) {
return ((Ps2File*)stream)->eof();
}
size_t ps2_fread(void *buf, size_t r, size_t n, FILE *stream) {
assert(r != 0);
return ((Ps2File*)stream)->read(buf, r * n) / r;
}
int ps2_fgetc(FILE *stream) {
uint8 temp;
if (((Ps2File*)stream)->read(&temp, 1))
return temp;
else
return EOF;
}
char *ps2_fgets(char *buf, int n, FILE *stream) {
char *retVal = buf;
while (n--) {
if (n == 0)
*buf = '\0';
else {
char c = ps2_fgetc(stream);
if (c == EOF)
return NULL;
if ((c == '\r') || (c == '\n')) {
*buf++ = '\0';
return retVal;
}
*buf++ = c;
}
}
return retVal;
}
int ps2_fprintf(FILE *pOut, const char *zFormat, ...) {
va_list ap;
char resStr[2048];
va_start(ap,zFormat);
int res = vsnprintf(resStr, 2048, zFormat, ap);
va_end(ap);
if ((pOut == stderr) || (pOut == stdout)) {
printf("%s", resStr);
sioprintf("%s", resStr);
} else
res = ps2_fwrite(resStr, 1, res, pOut);
return res;
}
size_t ps2_fwrite(const void *buf, size_t r, size_t n, FILE *stream) {
assert(r != 0);
return ((Ps2File*)stream)->write(buf, r * n) / r;
}
int ps2_fputc(int c, FILE *stream) {
if (((Ps2File*)stream)->write(&c, 1) == 1)
return c;
else
return -1;
}
int ps2_fputs(const char *s, FILE *stream) {
int len = strlen(s);
if (ps2_fwrite(s, 1, len, stream) == (size_t)len)
return len;
else
return EOF;
}
int ps2_fflush(FILE *stream) {
printf("fflush not implemented\n");
return 0;
}
TocManager::TocManager(void) {
_rootNode = NULL;
}
TocManager::~TocManager(void) {
// todo: write this...
}
bool TocManager::haveEntries(void) {
return _rootNode != NULL;
}
void TocManager::readEntries(const char *root) {
_rootLen = strlen(root);
strcpy(_root, root);
if (_root[_rootLen - 1] == '/') {
_rootLen--;
_root[_rootLen] = '\0';
}
readDir(_root, &_rootNode, 0);
}
#define MAX_DIR_ENTRIES 512
void TocManager::readDir(const char *path, TocNode **node, int level) {
if (level <= 2) { // we don't scan deeper than that
struct TocEntry tocEntries[MAX_DIR_ENTRIES];
int files = CDVD_GetDir(path + 5, NULL, CDVD_GET_FILES_AND_DIRS, tocEntries, MAX_DIR_ENTRIES, NULL);
for (int cnt = 0; cnt < files; cnt++) {
if (tocEntries[cnt].filename[0] != '.') { // skip '.' and '..'
*node = new TocNode;
(*node)->sub = (*node)->next = NULL;
(*node)->nameLen = strlen(tocEntries[cnt].filename);
memcpy((*node)->name, tocEntries[cnt].filename, (*node)->nameLen + 1);
if (tocEntries[cnt].fileProperties & 2) { // directory
(*node)->isDir = true;
char nextPath[256];
sprintf(nextPath, "%s/%s", path, tocEntries[cnt].filename);
readDir(nextPath, &((*node)->sub), level + 1);
} else
(*node)->isDir = false;
node = &((*node)->next);
}
}
}
}
int64 TocManager::fileExists(const char *name) {
if (((name[_rootLen] != '/') && (name[_rootLen] != '\0')) || (strnicmp(name, _root, _rootLen) != 0)) {
for (int i = 0; i < 8; i++)
if (name[i] == ':') // we don't know the content of other drives,
return -1; // assume file exists
else if ((name[i] == '/') || (name[i] == '\\'))
return 0; // does not exists (this is probably ScummVM trying the 'current directory'.)
return 0;
}
uint8 nameLen = strlen(name);
name += _rootLen + 1;
nameLen -= _rootLen + 1;
TocNode *node = _rootNode;
int64 retId = 1;
while (node) {
if (((name[node->nameLen] == '/') || (name[node->nameLen] == '\0')) && (strnicmp(name, node->name, node->nameLen) == 0)) {
name += node->nameLen;
nameLen -= node->nameLen;
if (node->isDir) {
if (nameLen) {
name++; // skip '/'
nameLen--;
node = node->sub;
retId <<= 10;
} else
return 0; // can't open a directory with fopen()
} else {
if (nameLen == 0)
return retId; // ok, found
else
return 0; // here's a file, but there's something left in the path
}
} else {
node = node->next;
retId++;
}
}
return 0; // does not exist
}
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