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/*
** 2006 Feb 14
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code that is specific to OS/2.
*/
#if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY)
/* os2safe.h has to be included before os2.h, needed for high mem */
#include <os2safe.h>
#endif
#include "sqliteInt.h"
#include "os.h"
#if OS_OS2
/*
** Macros used to determine whether or not to use threads.
*/
#if defined(THREADSAFE) && THREADSAFE
# define SQLITE_OS2_THREADS 1
#endif
/*
** Include code that is common to all os_*.c files
*/
#include "os_common.h"
/*
** The os2File structure is subclass of OsFile specific for the OS/2
** protability layer.
*/
typedef struct os2File os2File;
struct os2File {
IoMethod const *pMethod; /* Always the first entry */
HFILE h; /* Handle for accessing the file */
int delOnClose; /* True if file is to be deleted on close */
char* pathToDel; /* Name of file to delete on close */
unsigned char locktype; /* Type of lock currently held on this file */
};
/*
** Do not include any of the File I/O interface procedures if the
** SQLITE_OMIT_DISKIO macro is defined (indicating that there database
** will be in-memory only)
*/
#ifndef SQLITE_OMIT_DISKIO
/*
** Delete the named file
*/
int sqlite3Os2Delete( const char *zFilename ){
APIRET rc = NO_ERROR;
rc = DosDelete( (PSZ)zFilename );
TRACE2( "DELETE \"%s\"\n", zFilename );
return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}
/*
** Return TRUE if the named file exists.
*/
int sqlite3Os2FileExists( const char *zFilename ){
FILESTATUS3 fsts3ConfigInfo;
memset(&fsts3ConfigInfo, 0, sizeof(fsts3ConfigInfo));
return DosQueryPathInfo( (PSZ)zFilename, FIL_STANDARD,
&fsts3ConfigInfo, sizeof(FILESTATUS3) ) == NO_ERROR;
}
/* Forward declaration */
int allocateOs2File( os2File *pInit, OsFile **pld );
/*
** Attempt to open a file for both reading and writing. If that
** fails, try opening it read-only. If the file does not exist,
** try to create it.
**
** On success, a handle for the open file is written to *id
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only. The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3Os2OpenReadWrite(
const char *zFilename,
OsFile **pld,
int *pReadonly
){
os2File f;
HFILE hf;
ULONG ulAction;
APIRET rc = NO_ERROR;
assert( *pld == 0 );
rc = DosOpen( (PSZ)zFilename, &hf, &ulAction, 0L,
FILE_ARCHIVED | FILE_NORMAL,
OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS,
OPEN_FLAGS_FAIL_ON_ERROR | OPEN_FLAGS_RANDOM |
OPEN_SHARE_DENYNONE | OPEN_ACCESS_READWRITE, (PEAOP2)NULL );
if( rc != NO_ERROR ){
rc = DosOpen( (PSZ)zFilename, &hf, &ulAction, 0L,
FILE_ARCHIVED | FILE_NORMAL,
OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS,
OPEN_FLAGS_FAIL_ON_ERROR | OPEN_FLAGS_RANDOM |
OPEN_SHARE_DENYWRITE | OPEN_ACCESS_READONLY, (PEAOP2)NULL );
if( rc != NO_ERROR ){
return SQLITE_CANTOPEN;
}
*pReadonly = 1;
}
else{
*pReadonly = 0;
}
f.h = hf;
f.locktype = NO_LOCK;
f.delOnClose = 0;
f.pathToDel = NULL;
OpenCounter(+1);
TRACE3( "OPEN R/W %d \"%s\"\n", hf, zFilename );
return allocateOs2File( &f, pld );
}
/*
** Attempt to open a new file for exclusive access by this process.
** The file will be opened for both reading and writing. To avoid
** a potential security problem, we do not allow the file to have
** previously existed. Nor do we allow the file to be a symbolic
** link.
**
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3Os2OpenExclusive( const char *zFilename, OsFile **pld, int delFlag ){
os2File f;
HFILE hf;
ULONG ulAction;
APIRET rc = NO_ERROR;
assert( *pld == 0 );
rc = DosOpen( (PSZ)zFilename, &hf, &ulAction, 0L, FILE_NORMAL,
OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_REPLACE_IF_EXISTS,
OPEN_FLAGS_FAIL_ON_ERROR | OPEN_FLAGS_RANDOM |
OPEN_SHARE_DENYREADWRITE | OPEN_ACCESS_READWRITE, (PEAOP2)NULL );
if( rc != NO_ERROR ){
return SQLITE_CANTOPEN;
}
f.h = hf;
f.locktype = NO_LOCK;
f.delOnClose = delFlag ? 1 : 0;
f.pathToDel = delFlag ? sqlite3OsFullPathname( zFilename ) : NULL;
OpenCounter( +1 );
if( delFlag ) DosForceDelete( sqlite3OsFullPathname( zFilename ) );
TRACE3( "OPEN EX %d \"%s\"\n", hf, sqlite3OsFullPathname ( zFilename ) );
return allocateOs2File( &f, pld );
}
/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3Os2OpenReadOnly( const char *zFilename, OsFile **pld ){
os2File f;
HFILE hf;
ULONG ulAction;
APIRET rc = NO_ERROR;
assert( *pld == 0 );
rc = DosOpen( (PSZ)zFilename, &hf, &ulAction, 0L,
FILE_NORMAL, OPEN_ACTION_OPEN_IF_EXISTS,
OPEN_FLAGS_FAIL_ON_ERROR | OPEN_FLAGS_RANDOM |
OPEN_SHARE_DENYWRITE | OPEN_ACCESS_READONLY, (PEAOP2)NULL );
if( rc != NO_ERROR ){
return SQLITE_CANTOPEN;
}
f.h = hf;
f.locktype = NO_LOCK;
f.delOnClose = 0;
f.pathToDel = NULL;
OpenCounter( +1 );
TRACE3( "OPEN RO %d \"%s\"\n", hf, zFilename );
return allocateOs2File( &f, pld );
}
/*
** Attempt to open a file descriptor for the directory that contains a
** file. This file descriptor can be used to fsync() the directory
** in order to make sure the creation of a new file is actually written
** to disk.
**
** This routine is only meaningful for Unix. It is a no-op under
** OS/2 since OS/2 does not support hard links.
**
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
int os2OpenDirectory(
OsFile *id,
const char *zDirname
){
return SQLITE_OK;
}
/*
** If the following global variable points to a string which is the
** name of a directory, then that directory will be used to store
** temporary files.
*/
char *sqlite3_temp_directory = 0;
/*
** Create a temporary file name in zBuf. zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3Os2TempFileName( char *zBuf ){
static const unsigned char zChars[] =
"abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"0123456789";
int i, j;
PSZ zTempPath = 0;
if( DosScanEnv( "TEMP", &zTempPath ) ){
if( DosScanEnv( "TMP", &zTempPath ) ){
if( DosScanEnv( "TMPDIR", &zTempPath ) ){
ULONG ulDriveNum = 0, ulDriveMap = 0;
DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap );
sprintf( zTempPath, "%c:", (char)( 'A' + ulDriveNum - 1 ) );
}
}
}
for(;;){
sprintf( zBuf, "%s\\"TEMP_FILE_PREFIX, zTempPath );
j = strlen( zBuf );
sqlite3Randomness( 15, &zBuf[j] );
for( i = 0; i < 15; i++, j++ ){
zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
}
zBuf[j] = 0;
if( !sqlite3OsFileExists( zBuf ) ) break;
}
TRACE2( "TEMP FILENAME: %s\n", zBuf );
return SQLITE_OK;
}
/*
** Close a file.
*/
int os2Close( OsFile **pld ){
os2File *pFile;
APIRET rc = NO_ERROR;
if( pld && (pFile = (os2File*)*pld) != 0 ){
TRACE2( "CLOSE %d\n", pFile->h );
rc = DosClose( pFile->h );
pFile->locktype = NO_LOCK;
if( pFile->delOnClose != 0 ){
rc = DosForceDelete( pFile->pathToDel );
}
*pld = 0;
OpenCounter( -1 );
}
return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}
/*
** Read data from a file into a buffer. Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
int os2Read( OsFile *id, void *pBuf, int amt ){
ULONG got;
assert( id!=0 );
SimulateIOError( return SQLITE_IOERR );
TRACE3( "READ %d lock=%d\n", ((os2File*)id)->h, ((os2File*)id)->locktype );
DosRead( ((os2File*)id)->h, pBuf, amt, &got );
if (got == (ULONG)amt)
return SQLITE_OK;
else if (got < 0)
return SQLITE_IOERR_READ;
else {
memset(&((char*)pBuf)[got], 0, amt-got);
return SQLITE_IOERR_SHORT_READ;
}
}
/*
** Write data from a buffer into a file. Return SQLITE_OK on success
** or some other error code on failure.
*/
int os2Write( OsFile *id, const void *pBuf, int amt ){
APIRET rc = NO_ERROR;
ULONG wrote;
assert( id!=0 );
SimulateIOError( return SQLITE_IOERR );
SimulateDiskfullError( return SQLITE_FULL );
TRACE3( "WRITE %d lock=%d\n", ((os2File*)id)->h, ((os2File*)id)->locktype );
while( amt > 0 &&
(rc = DosWrite( ((os2File*)id)->h, (PVOID)pBuf, amt, &wrote )) && wrote > 0 ){
amt -= wrote;
pBuf = &((char*)pBuf)[wrote];
}
return ( rc != NO_ERROR || amt > (int)wrote ) ? SQLITE_FULL : SQLITE_OK;
}
/*
** Move the read/write pointer in a file.
*/
int os2Seek( OsFile *id, i64 offset ){
APIRET rc = NO_ERROR;
ULONG filePointer = 0L;
assert( id!=0 );
rc = DosSetFilePtr( ((os2File*)id)->h, offset, FILE_BEGIN, &filePointer );
TRACE3( "SEEK %d %lld\n", ((os2File*)id)->h, offset );
return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}
/*
** Make sure all writes to a particular file are committed to disk.
*/
int os2Sync( OsFile *id, int dataOnly ){
assert( id!=0 );
TRACE3( "SYNC %d lock=%d\n", ((os2File*)id)->h, ((os2File*)id)->locktype );
return DosResetBuffer( ((os2File*)id)->h ) == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}
/*
** Sync the directory zDirname. This is a no-op on operating systems other
** than UNIX.
*/
int sqlite3Os2SyncDirectory( const char *zDirname ){
SimulateIOError( return SQLITE_IOERR );
return SQLITE_OK;
}
/*
** Truncate an open file to a specified size
*/
int os2Truncate( OsFile *id, i64 nByte ){
APIRET rc = NO_ERROR;
ULONG upperBits = nByte>>32;
assert( id!=0 );
TRACE3( "TRUNCATE %d %lld\n", ((os2File*)id)->h, nByte );
SimulateIOError( return SQLITE_IOERR );
rc = DosSetFilePtr( ((os2File*)id)->h, nByte, FILE_BEGIN, &upperBits );
if( rc != NO_ERROR ){
return SQLITE_IOERR;
}
rc = DosSetFilePtr( ((os2File*)id)->h, 0L, FILE_END, &upperBits );
return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}
/*
** Determine the current size of a file in bytes
*/
int os2FileSize( OsFile *id, i64 *pSize ){
APIRET rc = NO_ERROR;
FILESTATUS3 fsts3FileInfo;
memset(&fsts3FileInfo, 0, sizeof(fsts3FileInfo));
assert( id!=0 );
SimulateIOError( return SQLITE_IOERR );
rc = DosQueryFileInfo( ((os2File*)id)->h, FIL_STANDARD, &fsts3FileInfo, sizeof(FILESTATUS3) );
if( rc == NO_ERROR ){
*pSize = fsts3FileInfo.cbFile;
return SQLITE_OK;
}
else{
return SQLITE_IOERR;
}
}
/*
** Acquire a reader lock.
*/
static int getReadLock( os2File *id ){
FILELOCK LockArea,
UnlockArea;
memset(&LockArea, 0, sizeof(LockArea));
memset(&UnlockArea, 0, sizeof(UnlockArea));
LockArea.lOffset = SHARED_FIRST;
LockArea.lRange = SHARED_SIZE;
UnlockArea.lOffset = 0L;
UnlockArea.lRange = 0L;
return DosSetFileLocks( id->h, &UnlockArea, &LockArea, 2000L, 1L );
}
/*
** Undo a readlock
*/
static int unlockReadLock( os2File *id ){
FILELOCK LockArea,
UnlockArea;
memset(&LockArea, 0, sizeof(LockArea));
memset(&UnlockArea, 0, sizeof(UnlockArea));
LockArea.lOffset = 0L;
LockArea.lRange = 0L;
UnlockArea.lOffset = SHARED_FIRST;
UnlockArea.lRange = SHARED_SIZE;
return DosSetFileLocks( id->h, &UnlockArea, &LockArea, 2000L, 1L );
}
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
/*
** Check that a given pathname is a directory and is writable
**
*/
int sqlite3Os2IsDirWritable( char *zDirname ){
FILESTATUS3 fsts3ConfigInfo;
APIRET rc = NO_ERROR;
memset(&fsts3ConfigInfo, 0, sizeof(fsts3ConfigInfo));
if( zDirname==0 ) return 0;
if( strlen(zDirname)>CCHMAXPATH ) return 0;
rc = DosQueryPathInfo( (PSZ)zDirname, FIL_STANDARD, &fsts3ConfigInfo, sizeof(FILESTATUS3) );
if( rc != NO_ERROR ) return 0;
if( (fsts3ConfigInfo.attrFile & FILE_DIRECTORY) != FILE_DIRECTORY ) return 0;
return 1;
}
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */
/*
** Lock the file with the lock specified by parameter locktype - one
** of the following:
**
** (1) SHARED_LOCK
** (2) RESERVED_LOCK
** (3) PENDING_LOCK
** (4) EXCLUSIVE_LOCK
**
** Sometimes when requesting one lock state, additional lock states
** are inserted in between. The locking might fail on one of the later
** transitions leaving the lock state different from what it started but
** still short of its goal. The following chart shows the allowed
** transitions and the inserted intermediate states:
**
** UNLOCKED -> SHARED
** SHARED -> RESERVED
** SHARED -> (PENDING) -> EXCLUSIVE
** RESERVED -> (PENDING) -> EXCLUSIVE
** PENDING -> EXCLUSIVE
**
** This routine will only increase a lock. The os2Unlock() routine
** erases all locks at once and returns us immediately to locking level 0.
** It is not possible to lower the locking level one step at a time. You
** must go straight to locking level 0.
*/
int os2Lock( OsFile *id, int locktype ){
APIRET rc = SQLITE_OK; /* Return code from subroutines */
APIRET res = NO_ERROR; /* Result of an OS/2 lock call */
int newLocktype; /* Set id->locktype to this value before exiting */
int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
FILELOCK LockArea,
UnlockArea;
os2File *pFile = (os2File*)id;
memset(&LockArea, 0, sizeof(LockArea));
memset(&UnlockArea, 0, sizeof(UnlockArea));
assert( pFile!=0 );
TRACE4( "LOCK %d %d was %d\n", pFile->h, locktype, pFile->locktype );
/* If there is already a lock of this type or more restrictive on the
** OsFile, do nothing. Don't use the end_lock: exit path, as
** sqlite3OsEnterMutex() hasn't been called yet.
*/
if( pFile->locktype>=locktype ){
return SQLITE_OK;
}
/* Make sure the locking sequence is correct
*/
assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
assert( locktype!=PENDING_LOCK );
assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
/* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
** a SHARED lock. If we are acquiring a SHARED lock, the acquisition of
** the PENDING_LOCK byte is temporary.
*/
newLocktype = pFile->locktype;
if( pFile->locktype==NO_LOCK
|| (locktype==EXCLUSIVE_LOCK && pFile->locktype==RESERVED_LOCK)
){
int cnt = 3;
LockArea.lOffset = PENDING_BYTE;
LockArea.lRange = 1L;
UnlockArea.lOffset = 0L;
UnlockArea.lRange = 0L;
while( cnt-->0 && (res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L) )!=NO_ERROR ){
/* Try 3 times to get the pending lock. The pending lock might be
** held by another reader process who will release it momentarily.
*/
TRACE2( "could not get a PENDING lock. cnt=%d\n", cnt );
DosSleep(1);
}
gotPendingLock = res;
}
/* Acquire a shared lock
*/
if( locktype==SHARED_LOCK && res ){
assert( pFile->locktype==NO_LOCK );
res = getReadLock(pFile);
if( res == NO_ERROR ){
newLocktype = SHARED_LOCK;
}
}
/* Acquire a RESERVED lock
*/
if( locktype==RESERVED_LOCK && res ){
assert( pFile->locktype==SHARED_LOCK );
LockArea.lOffset = RESERVED_BYTE;
LockArea.lRange = 1L;
UnlockArea.lOffset = 0L;
UnlockArea.lRange = 0L;
res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
if( res == NO_ERROR ){
newLocktype = RESERVED_LOCK;
}
}
/* Acquire a PENDING lock
*/
if( locktype==EXCLUSIVE_LOCK && res ){
newLocktype = PENDING_LOCK;
gotPendingLock = 0;
}
/* Acquire an EXCLUSIVE lock
*/
if( locktype==EXCLUSIVE_LOCK && res ){
assert( pFile->locktype>=SHARED_LOCK );
res = unlockReadLock(pFile);
TRACE2( "unreadlock = %d\n", res );
LockArea.lOffset = SHARED_FIRST;
LockArea.lRange = SHARED_SIZE;
UnlockArea.lOffset = 0L;
UnlockArea.lRange = 0L;
res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
if( res == NO_ERROR ){
newLocktype = EXCLUSIVE_LOCK;
}else{
TRACE2( "error-code = %d\n", res );
}
}
/* If we are holding a PENDING lock that ought to be released, then
** release it now.
*/
if( gotPendingLock && locktype==SHARED_LOCK ){
LockArea.lOffset = 0L;
LockArea.lRange = 0L;
UnlockArea.lOffset = PENDING_BYTE;
UnlockArea.lRange = 1L;
DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
}
/* Update the state of the lock has held in the file descriptor then
** return the appropriate result code.
*/
if( res == NO_ERROR ){
rc = SQLITE_OK;
}else{
TRACE4( "LOCK FAILED %d trying for %d but got %d\n", pFile->h,
locktype, newLocktype );
rc = SQLITE_BUSY;
}
pFile->locktype = newLocktype;
return rc;
}
/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero, otherwise zero.
*/
int os2CheckReservedLock( OsFile *id ){
APIRET rc = NO_ERROR;
os2File *pFile = (os2File*)id;
assert( pFile!=0 );
if( pFile->locktype>=RESERVED_LOCK ){
rc = 1;
TRACE3( "TEST WR-LOCK %d %d (local)\n", pFile->h, rc );
}else{
FILELOCK LockArea,
UnlockArea;
memset(&LockArea, 0, sizeof(LockArea));
memset(&UnlockArea, 0, sizeof(UnlockArea));
LockArea.lOffset = RESERVED_BYTE;
LockArea.lRange = 1L;
UnlockArea.lOffset = 0L;
UnlockArea.lRange = 0L;
rc = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
if( rc == NO_ERROR ){
LockArea.lOffset = 0L;
LockArea.lRange = 0L;
UnlockArea.lOffset = RESERVED_BYTE;
UnlockArea.lRange = 1L;
rc = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
}
TRACE3( "TEST WR-LOCK %d %d (remote)\n", pFile->h, rc );
}
return rc;
}
/*
** Lower the locking level on file descriptor id to locktype. locktype
** must be either NO_LOCK or SHARED_LOCK.
**
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK. If the second argument is SHARED_LOCK then this routine
** might return SQLITE_IOERR;
*/
int os2Unlock( OsFile *id, int locktype ){
int type;
APIRET rc = SQLITE_OK;
os2File *pFile = (os2File*)id;
FILELOCK LockArea,
UnlockArea;
memset(&LockArea, 0, sizeof(LockArea));
memset(&UnlockArea, 0, sizeof(UnlockArea));
assert( pFile!=0 );
assert( locktype<=SHARED_LOCK );
TRACE4( "UNLOCK %d to %d was %d\n", pFile->h, locktype, pFile->locktype );
type = pFile->locktype;
if( type>=EXCLUSIVE_LOCK ){
LockArea.lOffset = 0L;
LockArea.lRange = 0L;
UnlockArea.lOffset = SHARED_FIRST;
UnlockArea.lRange = SHARED_SIZE;
DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
if( locktype==SHARED_LOCK && getReadLock(pFile) != NO_ERROR ){
/* This should never happen. We should always be able to
** reacquire the read lock */
rc = SQLITE_IOERR;
}
}
if( type>=RESERVED_LOCK ){
LockArea.lOffset = 0L;
LockArea.lRange = 0L;
UnlockArea.lOffset = RESERVED_BYTE;
UnlockArea.lRange = 1L;
DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
}
if( locktype==NO_LOCK && type>=SHARED_LOCK ){
unlockReadLock(pFile);
}
if( type>=PENDING_LOCK ){
LockArea.lOffset = 0L;
LockArea.lRange = 0L;
UnlockArea.lOffset = PENDING_BYTE;
UnlockArea.lRange = 1L;
DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 2000L, 1L );
}
pFile->locktype = locktype;
return rc;
}
/*
** Turn a relative pathname into a full pathname. Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3Os2FullPathname( const char *zRelative ){
char *zFull = 0;
if( strchr(zRelative, ':') ){
sqlite3SetString( &zFull, zRelative, (char*)0 );
}else{
char zBuff[SQLITE_TEMPNAME_SIZE - 2] = {0};
char zDrive[1] = {0};
ULONG cbzFullLen = SQLITE_TEMPNAME_SIZE;
ULONG ulDriveNum = 0;
ULONG ulDriveMap = 0;
DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap );
DosQueryCurrentDir( 0L, zBuff, &cbzFullLen );
zFull = sqliteMalloc( cbzFullLen );
sprintf( zDrive, "%c", (char)('A' + ulDriveNum - 1) );
sqlite3SetString( &zFull, zDrive, ":\\", zBuff, "\\", zRelative, (char*)0 );
}
return zFull;
}
/*
** The fullSync option is meaningless on os2, or correct me if I'm wrong. This is a no-op.
** From os_unix.c: Change the value of the fullsync flag in the given file descriptor.
** From os_unix.c: ((unixFile*)id)->fullSync = v;
*/
static void os2SetFullSync( OsFile *id, int v ){
return;
}
/*
** Return the underlying file handle for an OsFile
*/
static int os2FileHandle( OsFile *id ){
return (int)((os2File*)id)->h;
}
/*
** Return an integer that indices the type of lock currently held
** by this handle. (Used for testing and analysis only.)
*/
static int os2LockState( OsFile *id ){
return ((os2File*)id)->locktype;
}
/*
** This vector defines all the methods that can operate on an OsFile
** for os2.
*/
static const IoMethod sqlite3Os2IoMethod = {
os2Close,
os2OpenDirectory,
os2Read,
os2Write,
os2Seek,
os2Truncate,
os2Sync,
os2SetFullSync,
os2FileHandle,
os2FileSize,
os2Lock,
os2Unlock,
os2LockState,
os2CheckReservedLock,
};
/*
** Allocate memory for an OsFile. Initialize the new OsFile
** to the value given in pInit and return a pointer to the new
** OsFile. If we run out of memory, close the file and return NULL.
*/
int allocateOs2File( os2File *pInit, OsFile **pld ){
os2File *pNew;
pNew = sqliteMalloc( sizeof(*pNew) );
if( pNew==0 ){
DosClose( pInit->h );
*pld = 0;
return SQLITE_NOMEM;
}else{
*pNew = *pInit;
pNew->pMethod = &sqlite3Os2IoMethod;
pNew->locktype = NO_LOCK;
*pld = (OsFile*)pNew;
OpenCounter(+1);
return SQLITE_OK;
}
}
#endif /* SQLITE_OMIT_DISKIO */
/***************************************************************************
** Everything above deals with file I/O. Everything that follows deals
** with other miscellanous aspects of the operating system interface
****************************************************************************/
#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
void *sqlite3Os2Dlopen(const char *zFilename){
UCHAR loadErr[256];
HMODULE hmod;
APIRET rc;
rc = DosLoadModule(loadErr, sizeof(loadErr), zFilename, &hmod);
if (rc != NO_ERROR) return 0;
return (void*)hmod;
}
void *sqlite3Os2Dlsym(void *pHandle, const char *zSymbol){
PFN pfn;
APIRET rc;
rc = DosQueryProcAddr((HMODULE)pHandle, 0L, zSymbol, &pfn);
if (rc != NO_ERROR) {
/* if the symbol itself was not found, search again for the same
* symbol with an extra underscore, that might be needed depending
* on the calling convention */
char _zSymbol[256] = "_";
strncat(_zSymbol, zSymbol, 255);
rc = DosQueryProcAddr((HMODULE)pHandle, 0L, _zSymbol, &pfn);
}
if (rc != NO_ERROR) return 0;
return pfn;
}
int sqlite3Os2Dlclose(void *pHandle){
return DosFreeModule((HMODULE)pHandle);
}
#endif /* SQLITE_OMIT_LOAD_EXTENSION */
/*
** Get information to seed the random number generator. The seed
** is written into the buffer zBuf[256]. The calling function must
** supply a sufficiently large buffer.
*/
int sqlite3Os2RandomSeed( char *zBuf ){
/* We have to initialize zBuf to prevent valgrind from reporting
** errors. The reports issued by valgrind are incorrect - we would
** prefer that the randomness be increased by making use of the
** uninitialized space in zBuf - but valgrind errors tend to worry
** some users. Rather than argue, it seems easier just to initialize
** the whole array and silence valgrind, even if that means less randomness
** in the random seed.
**
** When testing, initializing zBuf[] to zero is all we do. That means
** that we always use the same random number sequence. This makes the
** tests repeatable.
*/
memset( zBuf, 0, 256 );
DosGetDateTime( (PDATETIME)zBuf );
return SQLITE_OK;
}
/*
** Sleep for a little while. Return the amount of time slept.
*/
int sqlite3Os2Sleep( int ms ){
DosSleep( ms );
return ms;
}
/*
** Static variables used for thread synchronization
*/
static int inMutex = 0;
#ifdef SQLITE_OS2_THREADS
static ULONG mutexOwner;
#endif
/*
** The following pair of routines implement mutual exclusion for
** multi-threaded processes. Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex. There is not much critical
** code and what little there is executes quickly and without blocking.
*/
void sqlite3Os2EnterMutex(){
PTIB ptib;
#ifdef SQLITE_OS2_THREADS
DosEnterCritSec();
DosGetInfoBlocks( &ptib, NULL );
mutexOwner = ptib->tib_ptib2->tib2_ultid;
#endif
assert( !inMutex );
inMutex = 1;
}
void sqlite3Os2LeaveMutex(){
PTIB ptib;
assert( inMutex );
inMutex = 0;
#ifdef SQLITE_OS2_THREADS
DosGetInfoBlocks( &ptib, NULL );
assert( mutexOwner == ptib->tib_ptib2->tib2_ultid );
DosExitCritSec();
#endif
}
/*
** Return TRUE if the mutex is currently held.
**
** If the thisThreadOnly parameter is true, return true if and only if the
** calling thread holds the mutex. If the parameter is false, return
** true if any thread holds the mutex.
*/
int sqlite3Os2InMutex( int thisThreadOnly ){
#ifdef SQLITE_OS2_THREADS
PTIB ptib;
DosGetInfoBlocks( &ptib, NULL );
return inMutex>0 && (thisThreadOnly==0 || mutexOwner==ptib->tib_ptib2->tib2_ultid);
#else
return inMutex>0;
#endif
}
/*
** The following variable, if set to a non-zero value, becomes the result
** returned from sqlite3OsCurrentTime(). This is used for testing.
*/
#ifdef SQLITE_TEST
int sqlite3_current_time = 0;
#endif
/*
** Find the current time (in Universal Coordinated Time). Write the
** current time and date as a Julian Day number into *prNow and
** return 0. Return 1 if the time and date cannot be found.
*/
int sqlite3Os2CurrentTime( double *prNow ){
double now;
USHORT second, minute, hour,
day, month, year;
DATETIME dt;
DosGetDateTime( &dt );
second = (USHORT)dt.seconds;
minute = (USHORT)dt.minutes + dt.timezone;
hour = (USHORT)dt.hours;
day = (USHORT)dt.day;
month = (USHORT)dt.month;
year = (USHORT)dt.year;
/* Calculations from http://www.astro.keele.ac.uk/~rno/Astronomy/hjd.html
http://www.astro.keele.ac.uk/~rno/Astronomy/hjd-0.1.c */
/* Calculate the Julian days */
now = day - 32076 +
1461*(year + 4800 + (month - 14)/12)/4 +
367*(month - 2 - (month - 14)/12*12)/12 -
3*((year + 4900 + (month - 14)/12)/100)/4;
/* Add the fractional hours, mins and seconds */
now += (hour + 12.0)/24.0;
now += minute/1440.0;
now += second/86400.0;
*prNow = now;
#ifdef SQLITE_TEST
if( sqlite3_current_time ){
*prNow = sqlite3_current_time/86400.0 + 2440587.5;
}
#endif
return 0;
}
/*
** Remember the number of thread-specific-data blocks allocated.
** Use this to verify that we are not leaking thread-specific-data.
** Ticket #1601
*/
#ifdef SQLITE_TEST
int sqlite3_tsd_count = 0;
# define TSD_COUNTER_INCR InterlockedIncrement( &sqlite3_tsd_count )
# define TSD_COUNTER_DECR InterlockedDecrement( &sqlite3_tsd_count )
#else
# define TSD_COUNTER_INCR /* no-op */
# define TSD_COUNTER_DECR /* no-op */
#endif
/*
** If called with allocateFlag>1, then return a pointer to thread
** specific data for the current thread. Allocate and zero the
** thread-specific data if it does not already exist necessary.
**
** If called with allocateFlag==0, then check the current thread
** specific data. Return it if it exists. If it does not exist,
** then return NULL.
**
** If called with allocateFlag<0, check to see if the thread specific
** data is allocated and is all zero. If it is then deallocate it.
** Return a pointer to the thread specific data or NULL if it is
** unallocated or gets deallocated.
*/
ThreadData *sqlite3Os2ThreadSpecificData( int allocateFlag ){
static ThreadData **s_ppTsd = NULL;
static const ThreadData zeroData = {0, 0, 0};
ThreadData *pTsd;
if( !s_ppTsd ){
sqlite3OsEnterMutex();
if( !s_ppTsd ){
PULONG pul;
APIRET rc = DosAllocThreadLocalMemory(1, &pul);
if( rc != NO_ERROR ){
sqlite3OsLeaveMutex();
return 0;
}
s_ppTsd = (ThreadData **)pul;
}
sqlite3OsLeaveMutex();
}
pTsd = *s_ppTsd;
if( allocateFlag>0 ){
if( !pTsd ){
pTsd = sqlite3OsMalloc( sizeof(zeroData) );
if( pTsd ){
*pTsd = zeroData;
*s_ppTsd = pTsd;
TSD_COUNTER_INCR;
}
}
}else if( pTsd!=0 && allocateFlag<0
&& memcmp( pTsd, &zeroData, sizeof(ThreadData) )==0 ){
sqlite3OsFree(pTsd);
*s_ppTsd = NULL;
TSD_COUNTER_DECR;
pTsd = 0;
}
return pTsd;
}
#endif /* OS_OS2 */
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