From 2f8d7092bc2c9609fa98d6888106b96f38b22828 Mon Sep 17 00:00:00 2001 From: dan miller Date: Sun, 21 Oct 2007 08:36:32 +0000 Subject: libraries moved to opensim-libs, a new repository --- libraries/sqlite/unix/sqlite-3.5.1/src/os_unix.c | 2749 ---------------------- 1 file changed, 2749 deletions(-) delete mode 100644 libraries/sqlite/unix/sqlite-3.5.1/src/os_unix.c (limited to 'libraries/sqlite/unix/sqlite-3.5.1/src/os_unix.c') diff --git a/libraries/sqlite/unix/sqlite-3.5.1/src/os_unix.c b/libraries/sqlite/unix/sqlite-3.5.1/src/os_unix.c deleted file mode 100644 index e95435e..0000000 --- a/libraries/sqlite/unix/sqlite-3.5.1/src/os_unix.c +++ /dev/null @@ -1,2749 +0,0 @@ -/* -** 2004 May 22 -** -** 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 Unix systems. -*/ -#include "sqliteInt.h" -#if OS_UNIX /* This file is used on unix only */ - -/* #define SQLITE_ENABLE_LOCKING_STYLE 0 */ - -/* -** These #defines should enable >2GB file support on Posix if the -** underlying operating system supports it. If the OS lacks -** large file support, these should be no-ops. -** -** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch -** on the compiler command line. This is necessary if you are compiling -** on a recent machine (ex: RedHat 7.2) but you want your code to work -** on an older machine (ex: RedHat 6.0). If you compile on RedHat 7.2 -** without this option, LFS is enable. But LFS does not exist in the kernel -** in RedHat 6.0, so the code won't work. Hence, for maximum binary -** portability you should omit LFS. -*/ -#ifndef SQLITE_DISABLE_LFS -# define _LARGE_FILE 1 -# ifndef _FILE_OFFSET_BITS -# define _FILE_OFFSET_BITS 64 -# endif -# define _LARGEFILE_SOURCE 1 -#endif - -/* -** standard include files. -*/ -#include -#include -#include -#include -#include -#include -#include -#ifdef SQLITE_ENABLE_LOCKING_STYLE -#include -#include -#include -#endif /* SQLITE_ENABLE_LOCKING_STYLE */ - -/* -** If we are to be thread-safe, include the pthreads header and define -** the SQLITE_UNIX_THREADS macro. -*/ -#if SQLITE_THREADSAFE -# include -# define SQLITE_UNIX_THREADS 1 -#endif - -/* -** Default permissions when creating a new file -*/ -#ifndef SQLITE_DEFAULT_FILE_PERMISSIONS -# define SQLITE_DEFAULT_FILE_PERMISSIONS 0644 -#endif - -/* -** Maximum supported path-length. -*/ -#define MAX_PATHNAME 512 - - -/* -** The unixFile structure is subclass of sqlite3_file specific for the unix -** protability layer. -*/ -typedef struct unixFile unixFile; -struct unixFile { - sqlite3_io_methods const *pMethod; /* Always the first entry */ -#ifdef SQLITE_TEST - /* In test mode, increase the size of this structure a bit so that - ** it is larger than the struct CrashFile defined in test6.c. - */ - char aPadding[32]; -#endif - struct openCnt *pOpen; /* Info about all open fd's on this inode */ - struct lockInfo *pLock; /* Info about locks on this inode */ -#ifdef SQLITE_ENABLE_LOCKING_STYLE - void *lockingContext; /* Locking style specific state */ -#endif /* SQLITE_ENABLE_LOCKING_STYLE */ - int h; /* The file descriptor */ - unsigned char locktype; /* The type of lock held on this fd */ - int dirfd; /* File descriptor for the directory */ -#if SQLITE_THREADSAFE - pthread_t tid; /* The thread that "owns" this unixFile */ -#endif -}; - -/* -** Include code that is common to all os_*.c files -*/ -#include "os_common.h" - -/* -** Define various macros that are missing from some systems. -*/ -#ifndef O_LARGEFILE -# define O_LARGEFILE 0 -#endif -#ifdef SQLITE_DISABLE_LFS -# undef O_LARGEFILE -# define O_LARGEFILE 0 -#endif -#ifndef O_NOFOLLOW -# define O_NOFOLLOW 0 -#endif -#ifndef O_BINARY -# define O_BINARY 0 -#endif - -/* -** The DJGPP compiler environment looks mostly like Unix, but it -** lacks the fcntl() system call. So redefine fcntl() to be something -** that always succeeds. This means that locking does not occur under -** DJGPP. But it's DOS - what did you expect? -*/ -#ifdef __DJGPP__ -# define fcntl(A,B,C) 0 -#endif - -/* -** The threadid macro resolves to the thread-id or to 0. Used for -** testing and debugging only. -*/ -#if SQLITE_THREADSAFE -#define threadid pthread_self() -#else -#define threadid 0 -#endif - -/* -** Set or check the unixFile.tid field. This field is set when an unixFile -** is first opened. All subsequent uses of the unixFile verify that the -** same thread is operating on the unixFile. Some operating systems do -** not allow locks to be overridden by other threads and that restriction -** means that sqlite3* database handles cannot be moved from one thread -** to another. This logic makes sure a user does not try to do that -** by mistake. -** -** Version 3.3.1 (2006-01-15): unixFile can be moved from one thread to -** another as long as we are running on a system that supports threads -** overriding each others locks (which now the most common behavior) -** or if no locks are held. But the unixFile.pLock field needs to be -** recomputed because its key includes the thread-id. See the -** transferOwnership() function below for additional information -*/ -#if SQLITE_THREADSAFE -# define SET_THREADID(X) (X)->tid = pthread_self() -# define CHECK_THREADID(X) (threadsOverrideEachOthersLocks==0 && \ - !pthread_equal((X)->tid, pthread_self())) -#else -# define SET_THREADID(X) -# define CHECK_THREADID(X) 0 -#endif - -/* -** Here is the dirt on POSIX advisory locks: ANSI STD 1003.1 (1996) -** section 6.5.2.2 lines 483 through 490 specify that when a process -** sets or clears a lock, that operation overrides any prior locks set -** by the same process. It does not explicitly say so, but this implies -** that it overrides locks set by the same process using a different -** file descriptor. Consider this test case: -** -** int fd1 = open("./file1", O_RDWR|O_CREAT, 0644); -** int fd2 = open("./file2", O_RDWR|O_CREAT, 0644); -** -** Suppose ./file1 and ./file2 are really the same file (because -** one is a hard or symbolic link to the other) then if you set -** an exclusive lock on fd1, then try to get an exclusive lock -** on fd2, it works. I would have expected the second lock to -** fail since there was already a lock on the file due to fd1. -** But not so. Since both locks came from the same process, the -** second overrides the first, even though they were on different -** file descriptors opened on different file names. -** -** Bummer. If you ask me, this is broken. Badly broken. It means -** that we cannot use POSIX locks to synchronize file access among -** competing threads of the same process. POSIX locks will work fine -** to synchronize access for threads in separate processes, but not -** threads within the same process. -** -** To work around the problem, SQLite has to manage file locks internally -** on its own. Whenever a new database is opened, we have to find the -** specific inode of the database file (the inode is determined by the -** st_dev and st_ino fields of the stat structure that fstat() fills in) -** and check for locks already existing on that inode. When locks are -** created or removed, we have to look at our own internal record of the -** locks to see if another thread has previously set a lock on that same -** inode. -** -** The sqlite3_file structure for POSIX is no longer just an integer file -** descriptor. It is now a structure that holds the integer file -** descriptor and a pointer to a structure that describes the internal -** locks on the corresponding inode. There is one locking structure -** per inode, so if the same inode is opened twice, both unixFile structures -** point to the same locking structure. The locking structure keeps -** a reference count (so we will know when to delete it) and a "cnt" -** field that tells us its internal lock status. cnt==0 means the -** file is unlocked. cnt==-1 means the file has an exclusive lock. -** cnt>0 means there are cnt shared locks on the file. -** -** Any attempt to lock or unlock a file first checks the locking -** structure. The fcntl() system call is only invoked to set a -** POSIX lock if the internal lock structure transitions between -** a locked and an unlocked state. -** -** 2004-Jan-11: -** More recent discoveries about POSIX advisory locks. (The more -** I discover, the more I realize the a POSIX advisory locks are -** an abomination.) -** -** If you close a file descriptor that points to a file that has locks, -** all locks on that file that are owned by the current process are -** released. To work around this problem, each unixFile structure contains -** a pointer to an openCnt structure. There is one openCnt structure -** per open inode, which means that multiple unixFile can point to a single -** openCnt. When an attempt is made to close an unixFile, if there are -** other unixFile open on the same inode that are holding locks, the call -** to close() the file descriptor is deferred until all of the locks clear. -** The openCnt structure keeps a list of file descriptors that need to -** be closed and that list is walked (and cleared) when the last lock -** clears. -** -** First, under Linux threads, because each thread has a separate -** process ID, lock operations in one thread do not override locks -** to the same file in other threads. Linux threads behave like -** separate processes in this respect. But, if you close a file -** descriptor in linux threads, all locks are cleared, even locks -** on other threads and even though the other threads have different -** process IDs. Linux threads is inconsistent in this respect. -** (I'm beginning to think that linux threads is an abomination too.) -** The consequence of this all is that the hash table for the lockInfo -** structure has to include the process id as part of its key because -** locks in different threads are treated as distinct. But the -** openCnt structure should not include the process id in its -** key because close() clears lock on all threads, not just the current -** thread. Were it not for this goofiness in linux threads, we could -** combine the lockInfo and openCnt structures into a single structure. -** -** 2004-Jun-28: -** On some versions of linux, threads can override each others locks. -** On others not. Sometimes you can change the behavior on the same -** system by setting the LD_ASSUME_KERNEL environment variable. The -** POSIX standard is silent as to which behavior is correct, as far -** as I can tell, so other versions of unix might show the same -** inconsistency. There is no little doubt in my mind that posix -** advisory locks and linux threads are profoundly broken. -** -** To work around the inconsistencies, we have to test at runtime -** whether or not threads can override each others locks. This test -** is run once, the first time any lock is attempted. A static -** variable is set to record the results of this test for future -** use. -*/ - -/* -** An instance of the following structure serves as the key used -** to locate a particular lockInfo structure given its inode. -** -** If threads cannot override each others locks, then we set the -** lockKey.tid field to the thread ID. If threads can override -** each others locks then tid is always set to zero. tid is omitted -** if we compile without threading support. -*/ -struct lockKey { - dev_t dev; /* Device number */ - ino_t ino; /* Inode number */ -#if SQLITE_THREADSAFE - pthread_t tid; /* Thread ID or zero if threads can override each other */ -#endif -}; - -/* -** An instance of the following structure is allocated for each open -** inode on each thread with a different process ID. (Threads have -** different process IDs on linux, but not on most other unixes.) -** -** A single inode can have multiple file descriptors, so each unixFile -** structure contains a pointer to an instance of this object and this -** object keeps a count of the number of unixFile pointing to it. -*/ -struct lockInfo { - struct lockKey key; /* The lookup key */ - int cnt; /* Number of SHARED locks held */ - int locktype; /* One of SHARED_LOCK, RESERVED_LOCK etc. */ - int nRef; /* Number of pointers to this structure */ -}; - -/* -** An instance of the following structure serves as the key used -** to locate a particular openCnt structure given its inode. This -** is the same as the lockKey except that the thread ID is omitted. -*/ -struct openKey { - dev_t dev; /* Device number */ - ino_t ino; /* Inode number */ -}; - -/* -** An instance of the following structure is allocated for each open -** inode. This structure keeps track of the number of locks on that -** inode. If a close is attempted against an inode that is holding -** locks, the close is deferred until all locks clear by adding the -** file descriptor to be closed to the pending list. -*/ -struct openCnt { - struct openKey key; /* The lookup key */ - int nRef; /* Number of pointers to this structure */ - int nLock; /* Number of outstanding locks */ - int nPending; /* Number of pending close() operations */ - int *aPending; /* Malloced space holding fd's awaiting a close() */ -}; - -/* -** These hash tables map inodes and file descriptors (really, lockKey and -** openKey structures) into lockInfo and openCnt structures. Access to -** these hash tables must be protected by a mutex. -*/ -static Hash lockHash = {SQLITE_HASH_BINARY, 0, 0, 0, 0, 0}; -static Hash openHash = {SQLITE_HASH_BINARY, 0, 0, 0, 0, 0}; - -#ifdef SQLITE_ENABLE_LOCKING_STYLE -/* -** The locking styles are associated with the different file locking -** capabilities supported by different file systems. -** -** POSIX locking style fully supports shared and exclusive byte-range locks -** ADP locking only supports exclusive byte-range locks -** FLOCK only supports a single file-global exclusive lock -** DOTLOCK isn't a true locking style, it refers to the use of a special -** file named the same as the database file with a '.lock' extension, this -** can be used on file systems that do not offer any reliable file locking -** NO locking means that no locking will be attempted, this is only used for -** read-only file systems currently -** UNSUPPORTED means that no locking will be attempted, this is only used for -** file systems that are known to be unsupported -*/ -typedef enum { - posixLockingStyle = 0, /* standard posix-advisory locks */ - afpLockingStyle, /* use afp locks */ - flockLockingStyle, /* use flock() */ - dotlockLockingStyle, /* use .lock files */ - noLockingStyle, /* useful for read-only file system */ - unsupportedLockingStyle /* indicates unsupported file system */ -} sqlite3LockingStyle; -#endif /* SQLITE_ENABLE_LOCKING_STYLE */ - -/* -** Helper functions to obtain and relinquish the global mutex. -*/ -static void enterMutex(){ - sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER)); -} -static void leaveMutex(){ - sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER)); -} - -#if SQLITE_THREADSAFE -/* -** This variable records whether or not threads can override each others -** locks. -** -** 0: No. Threads cannot override each others locks. -** 1: Yes. Threads can override each others locks. -** -1: We don't know yet. -** -** On some systems, we know at compile-time if threads can override each -** others locks. On those systems, the SQLITE_THREAD_OVERRIDE_LOCK macro -** will be set appropriately. On other systems, we have to check at -** runtime. On these latter systems, SQLTIE_THREAD_OVERRIDE_LOCK is -** undefined. -** -** This variable normally has file scope only. But during testing, we make -** it a global so that the test code can change its value in order to verify -** that the right stuff happens in either case. -*/ -#ifndef SQLITE_THREAD_OVERRIDE_LOCK -# define SQLITE_THREAD_OVERRIDE_LOCK -1 -#endif -#ifdef SQLITE_TEST -int threadsOverrideEachOthersLocks = SQLITE_THREAD_OVERRIDE_LOCK; -#else -static int threadsOverrideEachOthersLocks = SQLITE_THREAD_OVERRIDE_LOCK; -#endif - -/* -** This structure holds information passed into individual test -** threads by the testThreadLockingBehavior() routine. -*/ -struct threadTestData { - int fd; /* File to be locked */ - struct flock lock; /* The locking operation */ - int result; /* Result of the locking operation */ -}; - -#ifdef SQLITE_LOCK_TRACE -/* -** Print out information about all locking operations. -** -** This routine is used for troubleshooting locks on multithreaded -** platforms. Enable by compiling with the -DSQLITE_LOCK_TRACE -** command-line option on the compiler. This code is normally -** turned off. -*/ -static int lockTrace(int fd, int op, struct flock *p){ - char *zOpName, *zType; - int s; - int savedErrno; - if( op==F_GETLK ){ - zOpName = "GETLK"; - }else if( op==F_SETLK ){ - zOpName = "SETLK"; - }else{ - s = fcntl(fd, op, p); - sqlite3DebugPrintf("fcntl unknown %d %d %d\n", fd, op, s); - return s; - } - if( p->l_type==F_RDLCK ){ - zType = "RDLCK"; - }else if( p->l_type==F_WRLCK ){ - zType = "WRLCK"; - }else if( p->l_type==F_UNLCK ){ - zType = "UNLCK"; - }else{ - assert( 0 ); - } - assert( p->l_whence==SEEK_SET ); - s = fcntl(fd, op, p); - savedErrno = errno; - sqlite3DebugPrintf("fcntl %d %d %s %s %d %d %d %d\n", - threadid, fd, zOpName, zType, (int)p->l_start, (int)p->l_len, - (int)p->l_pid, s); - if( s==(-1) && op==F_SETLK && (p->l_type==F_RDLCK || p->l_type==F_WRLCK) ){ - struct flock l2; - l2 = *p; - fcntl(fd, F_GETLK, &l2); - if( l2.l_type==F_RDLCK ){ - zType = "RDLCK"; - }else if( l2.l_type==F_WRLCK ){ - zType = "WRLCK"; - }else if( l2.l_type==F_UNLCK ){ - zType = "UNLCK"; - }else{ - assert( 0 ); - } - sqlite3DebugPrintf("fcntl-failure-reason: %s %d %d %d\n", - zType, (int)l2.l_start, (int)l2.l_len, (int)l2.l_pid); - } - errno = savedErrno; - return s; -} -#define fcntl lockTrace -#endif /* SQLITE_LOCK_TRACE */ - -/* -** The testThreadLockingBehavior() routine launches two separate -** threads on this routine. This routine attempts to lock a file -** descriptor then returns. The success or failure of that attempt -** allows the testThreadLockingBehavior() procedure to determine -** whether or not threads can override each others locks. -*/ -static void *threadLockingTest(void *pArg){ - struct threadTestData *pData = (struct threadTestData*)pArg; - pData->result = fcntl(pData->fd, F_SETLK, &pData->lock); - return pArg; -} - -/* -** This procedure attempts to determine whether or not threads -** can override each others locks then sets the -** threadsOverrideEachOthersLocks variable appropriately. -*/ -static void testThreadLockingBehavior(int fd_orig){ - int fd; - struct threadTestData d[2]; - pthread_t t[2]; - - fd = dup(fd_orig); - if( fd<0 ) return; - memset(d, 0, sizeof(d)); - d[0].fd = fd; - d[0].lock.l_type = F_RDLCK; - d[0].lock.l_len = 1; - d[0].lock.l_start = 0; - d[0].lock.l_whence = SEEK_SET; - d[1] = d[0]; - d[1].lock.l_type = F_WRLCK; - pthread_create(&t[0], 0, threadLockingTest, &d[0]); - pthread_create(&t[1], 0, threadLockingTest, &d[1]); - pthread_join(t[0], 0); - pthread_join(t[1], 0); - close(fd); - threadsOverrideEachOthersLocks = d[0].result==0 && d[1].result==0; -} -#endif /* SQLITE_THREADSAFE */ - -/* -** Release a lockInfo structure previously allocated by findLockInfo(). -*/ -static void releaseLockInfo(struct lockInfo *pLock){ - if (pLock == NULL) - return; - pLock->nRef--; - if( pLock->nRef==0 ){ - sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0); - sqlite3_free(pLock); - } -} - -/* -** Release a openCnt structure previously allocated by findLockInfo(). -*/ -static void releaseOpenCnt(struct openCnt *pOpen){ - if (pOpen == NULL) - return; - pOpen->nRef--; - if( pOpen->nRef==0 ){ - sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0); - free(pOpen->aPending); - sqlite3_free(pOpen); - } -} - -#ifdef SQLITE_ENABLE_LOCKING_STYLE -/* -** Tests a byte-range locking query to see if byte range locks are -** supported, if not we fall back to dotlockLockingStyle. -*/ -static sqlite3LockingStyle sqlite3TestLockingStyle( - const char *filePath, - int fd -){ - /* test byte-range lock using fcntl */ - struct flock lockInfo; - - lockInfo.l_len = 1; - lockInfo.l_start = 0; - lockInfo.l_whence = SEEK_SET; - lockInfo.l_type = F_RDLCK; - - if( fcntl(fd, F_GETLK, &lockInfo)!=-1 ) { - return posixLockingStyle; - } - - /* testing for flock can give false positives. So if if the above test - ** fails, then we fall back to using dot-lock style locking. - */ - return dotlockLockingStyle; -} - -/* -** Examines the f_fstypename entry in the statfs structure as returned by -** stat() for the file system hosting the database file, assigns the -** appropriate locking style based on it's value. These values and -** assignments are based on Darwin/OSX behavior and have not been tested on -** other systems. -*/ -static sqlite3LockingStyle sqlite3DetectLockingStyle( - const char *filePath, - int fd -){ - -#ifdef SQLITE_FIXED_LOCKING_STYLE - return (sqlite3LockingStyle)SQLITE_FIXED_LOCKING_STYLE; -#else - struct statfs fsInfo; - - if (statfs(filePath, &fsInfo) == -1) - return sqlite3TestLockingStyle(filePath, fd); - - if (fsInfo.f_flags & MNT_RDONLY) - return noLockingStyle; - - if( (!strcmp(fsInfo.f_fstypename, "hfs")) || - (!strcmp(fsInfo.f_fstypename, "ufs")) ) - return posixLockingStyle; - - if(!strcmp(fsInfo.f_fstypename, "afpfs")) - return afpLockingStyle; - - if(!strcmp(fsInfo.f_fstypename, "nfs")) - return sqlite3TestLockingStyle(filePath, fd); - - if(!strcmp(fsInfo.f_fstypename, "smbfs")) - return flockLockingStyle; - - if(!strcmp(fsInfo.f_fstypename, "msdos")) - return dotlockLockingStyle; - - if(!strcmp(fsInfo.f_fstypename, "webdav")) - return unsupportedLockingStyle; - - return sqlite3TestLockingStyle(filePath, fd); -#endif /* SQLITE_FIXED_LOCKING_STYLE */ -} - -#endif /* SQLITE_ENABLE_LOCKING_STYLE */ - -/* -** Given a file descriptor, locate lockInfo and openCnt structures that -** describes that file descriptor. Create new ones if necessary. The -** return values might be uninitialized if an error occurs. -** -** Return the number of errors. -*/ -static int findLockInfo( - int fd, /* The file descriptor used in the key */ - struct lockInfo **ppLock, /* Return the lockInfo structure here */ - struct openCnt **ppOpen /* Return the openCnt structure here */ -){ - int rc; - struct lockKey key1; - struct openKey key2; - struct stat statbuf; - struct lockInfo *pLock; - struct openCnt *pOpen; - rc = fstat(fd, &statbuf); - if( rc!=0 ) return 1; - - memset(&key1, 0, sizeof(key1)); - key1.dev = statbuf.st_dev; - key1.ino = statbuf.st_ino; -#if SQLITE_THREADSAFE - if( threadsOverrideEachOthersLocks<0 ){ - testThreadLockingBehavior(fd); - } - key1.tid = threadsOverrideEachOthersLocks ? 0 : pthread_self(); -#endif - memset(&key2, 0, sizeof(key2)); - key2.dev = statbuf.st_dev; - key2.ino = statbuf.st_ino; - pLock = (struct lockInfo*)sqlite3HashFind(&lockHash, &key1, sizeof(key1)); - if( pLock==0 ){ - struct lockInfo *pOld; - pLock = sqlite3_malloc( sizeof(*pLock) ); - if( pLock==0 ){ - rc = 1; - goto exit_findlockinfo; - } - pLock->key = key1; - pLock->nRef = 1; - pLock->cnt = 0; - pLock->locktype = 0; - pOld = sqlite3HashInsert(&lockHash, &pLock->key, sizeof(key1), pLock); - if( pOld!=0 ){ - assert( pOld==pLock ); - sqlite3_free(pLock); - rc = 1; - goto exit_findlockinfo; - } - }else{ - pLock->nRef++; - } - *ppLock = pLock; - if( ppOpen!=0 ){ - pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2)); - if( pOpen==0 ){ - struct openCnt *pOld; - pOpen = sqlite3_malloc( sizeof(*pOpen) ); - if( pOpen==0 ){ - releaseLockInfo(pLock); - rc = 1; - goto exit_findlockinfo; - } - pOpen->key = key2; - pOpen->nRef = 1; - pOpen->nLock = 0; - pOpen->nPending = 0; - pOpen->aPending = 0; - pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen); - if( pOld!=0 ){ - assert( pOld==pOpen ); - sqlite3_free(pOpen); - releaseLockInfo(pLock); - rc = 1; - goto exit_findlockinfo; - } - }else{ - pOpen->nRef++; - } - *ppOpen = pOpen; - } - -exit_findlockinfo: - return rc; -} - -#ifdef SQLITE_DEBUG -/* -** Helper function for printing out trace information from debugging -** binaries. This returns the string represetation of the supplied -** integer lock-type. -*/ -static const char *locktypeName(int locktype){ - switch( locktype ){ - case NO_LOCK: return "NONE"; - case SHARED_LOCK: return "SHARED"; - case RESERVED_LOCK: return "RESERVED"; - case PENDING_LOCK: return "PENDING"; - case EXCLUSIVE_LOCK: return "EXCLUSIVE"; - } - return "ERROR"; -} -#endif - -/* -** If we are currently in a different thread than the thread that the -** unixFile argument belongs to, then transfer ownership of the unixFile -** over to the current thread. -** -** A unixFile is only owned by a thread on systems where one thread is -** unable to override locks created by a different thread. RedHat9 is -** an example of such a system. -** -** Ownership transfer is only allowed if the unixFile is currently unlocked. -** If the unixFile is locked and an ownership is wrong, then return -** SQLITE_MISUSE. SQLITE_OK is returned if everything works. -*/ -#if SQLITE_THREADSAFE -static int transferOwnership(unixFile *pFile){ - int rc; - pthread_t hSelf; - if( threadsOverrideEachOthersLocks ){ - /* Ownership transfers not needed on this system */ - return SQLITE_OK; - } - hSelf = pthread_self(); - if( pthread_equal(pFile->tid, hSelf) ){ - /* We are still in the same thread */ - OSTRACE1("No-transfer, same thread\n"); - return SQLITE_OK; - } - if( pFile->locktype!=NO_LOCK ){ - /* We cannot change ownership while we are holding a lock! */ - return SQLITE_MISUSE; - } - OSTRACE4("Transfer ownership of %d from %d to %d\n", - pFile->h, pFile->tid, hSelf); - pFile->tid = hSelf; - if (pFile->pLock != NULL) { - releaseLockInfo(pFile->pLock); - rc = findLockInfo(pFile->h, &pFile->pLock, 0); - OSTRACE5("LOCK %d is now %s(%s,%d)\n", pFile->h, - locktypeName(pFile->locktype), - locktypeName(pFile->pLock->locktype), pFile->pLock->cnt); - return rc; - } else { - return SQLITE_OK; - } -} -#else - /* On single-threaded builds, ownership transfer is a no-op */ -# define transferOwnership(X) SQLITE_OK -#endif - -/* -** Seek to the offset passed as the second argument, then read cnt -** bytes into pBuf. Return the number of bytes actually read. -*/ -static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){ - int got; - i64 newOffset; - TIMER_START; -#if defined(USE_PREAD) - got = pread(id->h, pBuf, cnt, offset); - SimulateIOError( got = -1 ); -#elif defined(USE_PREAD64) - got = pread64(id->h, pBuf, cnt, offset); - SimulateIOError( got = -1 ); -#else - newOffset = lseek(id->h, offset, SEEK_SET); - SimulateIOError( newOffset-- ); - if( newOffset!=offset ){ - return -1; - } - got = read(id->h, pBuf, cnt); -#endif - TIMER_END; - OSTRACE5("READ %-3d %5d %7lld %d\n", id->h, got, offset, TIMER_ELAPSED); - return got; -} - -/* -** Read data from a file into a buffer. Return SQLITE_OK if all -** bytes were read successfully and SQLITE_IOERR if anything goes -** wrong. -*/ -static int unixRead( - sqlite3_file *id, - void *pBuf, - int amt, - sqlite3_int64 offset -){ - int got; - assert( id ); - got = seekAndRead((unixFile*)id, offset, pBuf, amt); - if( got==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; - } -} - -/* -** Seek to the offset in id->offset then read cnt bytes into pBuf. -** Return the number of bytes actually read. Update the offset. -*/ -static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){ - int got; - i64 newOffset; - TIMER_START; -#if defined(USE_PREAD) - got = pwrite(id->h, pBuf, cnt, offset); -#elif defined(USE_PREAD64) - got = pwrite64(id->h, pBuf, cnt, offset); -#else - newOffset = lseek(id->h, offset, SEEK_SET); - if( newOffset!=offset ){ - return -1; - } - got = write(id->h, pBuf, cnt); -#endif - TIMER_END; - OSTRACE5("WRITE %-3d %5d %7lld %d\n", id->h, got, offset, TIMER_ELAPSED); - return got; -} - - -/* -** Write data from a buffer into a file. Return SQLITE_OK on success -** or some other error code on failure. -*/ -static int unixWrite( - sqlite3_file *id, - const void *pBuf, - int amt, - sqlite3_int64 offset -){ - int wrote = 0; - assert( id ); - assert( amt>0 ); - while( amt>0 && (wrote = seekAndWrite((unixFile*)id, offset, pBuf, amt))>0 ){ - amt -= wrote; - offset += wrote; - pBuf = &((char*)pBuf)[wrote]; - } - SimulateIOError(( wrote=(-1), amt=1 )); - SimulateDiskfullError(( wrote=0, amt=1 )); - if( amt>0 ){ - if( wrote<0 ){ - return SQLITE_IOERR_WRITE; - }else{ - return SQLITE_FULL; - } - } - return SQLITE_OK; -} - -#ifdef SQLITE_TEST -/* -** Count the number of fullsyncs and normal syncs. This is used to test -** that syncs and fullsyncs are occuring at the right times. -*/ -int sqlite3_sync_count = 0; -int sqlite3_fullsync_count = 0; -#endif - -/* -** Use the fdatasync() API only if the HAVE_FDATASYNC macro is defined. -** Otherwise use fsync() in its place. -*/ -#ifndef HAVE_FDATASYNC -# define fdatasync fsync -#endif - -/* -** Define HAVE_FULLFSYNC to 0 or 1 depending on whether or not -** the F_FULLFSYNC macro is defined. F_FULLFSYNC is currently -** only available on Mac OS X. But that could change. -*/ -#ifdef F_FULLFSYNC -# define HAVE_FULLFSYNC 1 -#else -# define HAVE_FULLFSYNC 0 -#endif - - -/* -** The fsync() system call does not work as advertised on many -** unix systems. The following procedure is an attempt to make -** it work better. -** -** The SQLITE_NO_SYNC macro disables all fsync()s. This is useful -** for testing when we want to run through the test suite quickly. -** You are strongly advised *not* to deploy with SQLITE_NO_SYNC -** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash -** or power failure will likely corrupt the database file. -*/ -static int full_fsync(int fd, int fullSync, int dataOnly){ - int rc; - - /* Record the number of times that we do a normal fsync() and - ** FULLSYNC. This is used during testing to verify that this procedure - ** gets called with the correct arguments. - */ -#ifdef SQLITE_TEST - if( fullSync ) sqlite3_fullsync_count++; - sqlite3_sync_count++; -#endif - - /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a - ** no-op - */ -#ifdef SQLITE_NO_SYNC - rc = SQLITE_OK; -#else - -#if HAVE_FULLFSYNC - if( fullSync ){ - rc = fcntl(fd, F_FULLFSYNC, 0); - }else{ - rc = 1; - } - /* If the FULLFSYNC failed, fall back to attempting an fsync(). - * It shouldn't be possible for fullfsync to fail on the local - * file system (on OSX), so failure indicates that FULLFSYNC - * isn't supported for this file system. So, attempt an fsync - * and (for now) ignore the overhead of a superfluous fcntl call. - * It'd be better to detect fullfsync support once and avoid - * the fcntl call every time sync is called. - */ - if( rc ) rc = fsync(fd); - -#else - if( dataOnly ){ - rc = fdatasync(fd); - }else{ - rc = fsync(fd); - } -#endif /* HAVE_FULLFSYNC */ -#endif /* defined(SQLITE_NO_SYNC) */ - - return rc; -} - -/* -** Make sure all writes to a particular file are committed to disk. -** -** If dataOnly==0 then both the file itself and its metadata (file -** size, access time, etc) are synced. If dataOnly!=0 then only the -** file data is synced. -** -** Under Unix, also make sure that the directory entry for the file -** has been created by fsync-ing the directory that contains the file. -** If we do not do this and we encounter a power failure, the directory -** entry for the journal might not exist after we reboot. The next -** SQLite to access the file will not know that the journal exists (because -** the directory entry for the journal was never created) and the transaction -** will not roll back - possibly leading to database corruption. -*/ -static int unixSync(sqlite3_file *id, int flags){ - int rc; - unixFile *pFile = (unixFile*)id; - - int isDataOnly = (flags&SQLITE_SYNC_DATAONLY); - int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL; - - /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */ - assert((flags&0x0F)==SQLITE_SYNC_NORMAL - || (flags&0x0F)==SQLITE_SYNC_FULL - ); - - assert( pFile ); - OSTRACE2("SYNC %-3d\n", pFile->h); - rc = full_fsync(pFile->h, isFullsync, isDataOnly); - SimulateIOError( rc=1 ); - if( rc ){ - return SQLITE_IOERR_FSYNC; - } - if( pFile->dirfd>=0 ){ - OSTRACE4("DIRSYNC %-3d (have_fullfsync=%d fullsync=%d)\n", pFile->dirfd, - HAVE_FULLFSYNC, isFullsync); -#ifndef SQLITE_DISABLE_DIRSYNC - /* The directory sync is only attempted if full_fsync is - ** turned off or unavailable. If a full_fsync occurred above, - ** then the directory sync is superfluous. - */ - if( (!HAVE_FULLFSYNC || !isFullsync) && full_fsync(pFile->dirfd,0,0) ){ - /* - ** We have received multiple reports of fsync() returning - ** errors when applied to directories on certain file systems. - ** A failed directory sync is not a big deal. So it seems - ** better to ignore the error. Ticket #1657 - */ - /* return SQLITE_IOERR; */ - } -#endif - close(pFile->dirfd); /* Only need to sync once, so close the directory */ - pFile->dirfd = -1; /* when we are done. */ - } - return SQLITE_OK; -} - -/* -** Truncate an open file to a specified size -*/ -static int unixTruncate(sqlite3_file *id, i64 nByte){ - int rc; - assert( id ); - rc = ftruncate(((unixFile*)id)->h, (off_t)nByte); - SimulateIOError( rc=1 ); - if( rc ){ - return SQLITE_IOERR_TRUNCATE; - }else{ - return SQLITE_OK; - } -} - -/* -** Determine the current size of a file in bytes -*/ -static int unixFileSize(sqlite3_file *id, i64 *pSize){ - int rc; - struct stat buf; - assert( id ); - rc = fstat(((unixFile*)id)->h, &buf); - SimulateIOError( rc=1 ); - if( rc!=0 ){ - return SQLITE_IOERR_FSTAT; - } - *pSize = buf.st_size; - return SQLITE_OK; -} - -/* -** 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. If the file is unlocked or holds only SHARED locks, then -** return zero. -*/ -static int unixCheckReservedLock(sqlite3_file *id){ - int r = 0; - unixFile *pFile = (unixFile*)id; - - assert( pFile ); - enterMutex(); /* Because pFile->pLock is shared across threads */ - - /* Check if a thread in this process holds such a lock */ - if( pFile->pLock->locktype>SHARED_LOCK ){ - r = 1; - } - - /* Otherwise see if some other process holds it. - */ - if( !r ){ - struct flock lock; - lock.l_whence = SEEK_SET; - lock.l_start = RESERVED_BYTE; - lock.l_len = 1; - lock.l_type = F_WRLCK; - fcntl(pFile->h, F_GETLK, &lock); - if( lock.l_type!=F_UNLCK ){ - r = 1; - } - } - - leaveMutex(); - OSTRACE3("TEST WR-LOCK %d %d\n", pFile->h, r); - - return r; -} - -/* -** 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. Use the sqlite3OsUnlock() -** routine to lower a locking level. -*/ -static int unixLock(sqlite3_file *id, int locktype){ - /* The following describes the implementation of the various locks and - ** lock transitions in terms of the POSIX advisory shared and exclusive - ** lock primitives (called read-locks and write-locks below, to avoid - ** confusion with SQLite lock names). The algorithms are complicated - ** slightly in order to be compatible with windows systems simultaneously - ** accessing the same database file, in case that is ever required. - ** - ** Symbols defined in os.h indentify the 'pending byte' and the 'reserved - ** byte', each single bytes at well known offsets, and the 'shared byte - ** range', a range of 510 bytes at a well known offset. - ** - ** To obtain a SHARED lock, a read-lock is obtained on the 'pending - ** byte'. If this is successful, a random byte from the 'shared byte - ** range' is read-locked and the lock on the 'pending byte' released. - ** - ** A process may only obtain a RESERVED lock after it has a SHARED lock. - ** A RESERVED lock is implemented by grabbing a write-lock on the - ** 'reserved byte'. - ** - ** A process may only obtain a PENDING lock after it has obtained a - ** SHARED lock. A PENDING lock is implemented by obtaining a write-lock - ** on the 'pending byte'. This ensures that no new SHARED locks can be - ** obtained, but existing SHARED locks are allowed to persist. A process - ** does not have to obtain a RESERVED lock on the way to a PENDING lock. - ** This property is used by the algorithm for rolling back a journal file - ** after a crash. - ** - ** An EXCLUSIVE lock, obtained after a PENDING lock is held, is - ** implemented by obtaining a write-lock on the entire 'shared byte - ** range'. Since all other locks require a read-lock on one of the bytes - ** within this range, this ensures that no other locks are held on the - ** database. - ** - ** The reason a single byte cannot be used instead of the 'shared byte - ** range' is that some versions of windows do not support read-locks. By - ** locking a random byte from a range, concurrent SHARED locks may exist - ** even if the locking primitive used is always a write-lock. - */ - int rc = SQLITE_OK; - unixFile *pFile = (unixFile*)id; - struct lockInfo *pLock = pFile->pLock; - struct flock lock; - int s; - - assert( pFile ); - OSTRACE7("LOCK %d %s was %s(%s,%d) pid=%d\n", pFile->h, - locktypeName(locktype), locktypeName(pFile->locktype), - locktypeName(pLock->locktype), pLock->cnt , getpid()); - - /* If there is already a lock of this type or more restrictive on the - ** unixFile, do nothing. Don't use the end_lock: exit path, as - ** enterMutex() hasn't been called yet. - */ - if( pFile->locktype>=locktype ){ - OSTRACE3("LOCK %d %s ok (already held)\n", pFile->h, - locktypeName(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 ); - - /* This mutex is needed because pFile->pLock is shared across threads - */ - enterMutex(); - - /* Make sure the current thread owns the pFile. - */ - rc = transferOwnership(pFile); - if( rc!=SQLITE_OK ){ - leaveMutex(); - return rc; - } - pLock = pFile->pLock; - - /* If some thread using this PID has a lock via a different unixFile* - ** handle that precludes the requested lock, return BUSY. - */ - if( (pFile->locktype!=pLock->locktype && - (pLock->locktype>=PENDING_LOCK || locktype>SHARED_LOCK)) - ){ - rc = SQLITE_BUSY; - goto end_lock; - } - - /* If a SHARED lock is requested, and some thread using this PID already - ** has a SHARED or RESERVED lock, then increment reference counts and - ** return SQLITE_OK. - */ - if( locktype==SHARED_LOCK && - (pLock->locktype==SHARED_LOCK || pLock->locktype==RESERVED_LOCK) ){ - assert( locktype==SHARED_LOCK ); - assert( pFile->locktype==0 ); - assert( pLock->cnt>0 ); - pFile->locktype = SHARED_LOCK; - pLock->cnt++; - pFile->pOpen->nLock++; - goto end_lock; - } - - lock.l_len = 1L; - - lock.l_whence = SEEK_SET; - - /* A PENDING lock is needed before acquiring a SHARED lock and before - ** acquiring an EXCLUSIVE lock. For the SHARED lock, the PENDING will - ** be released. - */ - if( locktype==SHARED_LOCK - || (locktype==EXCLUSIVE_LOCK && pFile->locktypeh, F_SETLK, &lock); - if( s==(-1) ){ - rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY; - goto end_lock; - } - } - - - /* If control gets to this point, then actually go ahead and make - ** operating system calls for the specified lock. - */ - if( locktype==SHARED_LOCK ){ - assert( pLock->cnt==0 ); - assert( pLock->locktype==0 ); - - /* Now get the read-lock */ - lock.l_start = SHARED_FIRST; - lock.l_len = SHARED_SIZE; - s = fcntl(pFile->h, F_SETLK, &lock); - - /* Drop the temporary PENDING lock */ - lock.l_start = PENDING_BYTE; - lock.l_len = 1L; - lock.l_type = F_UNLCK; - if( fcntl(pFile->h, F_SETLK, &lock)!=0 ){ - rc = SQLITE_IOERR_UNLOCK; /* This should never happen */ - goto end_lock; - } - if( s==(-1) ){ - rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY; - }else{ - pFile->locktype = SHARED_LOCK; - pFile->pOpen->nLock++; - pLock->cnt = 1; - } - }else if( locktype==EXCLUSIVE_LOCK && pLock->cnt>1 ){ - /* We are trying for an exclusive lock but another thread in this - ** same process is still holding a shared lock. */ - rc = SQLITE_BUSY; - }else{ - /* The request was for a RESERVED or EXCLUSIVE lock. It is - ** assumed that there is a SHARED or greater lock on the file - ** already. - */ - assert( 0!=pFile->locktype ); - lock.l_type = F_WRLCK; - switch( locktype ){ - case RESERVED_LOCK: - lock.l_start = RESERVED_BYTE; - break; - case EXCLUSIVE_LOCK: - lock.l_start = SHARED_FIRST; - lock.l_len = SHARED_SIZE; - break; - default: - assert(0); - } - s = fcntl(pFile->h, F_SETLK, &lock); - if( s==(-1) ){ - rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY; - } - } - - if( rc==SQLITE_OK ){ - pFile->locktype = locktype; - pLock->locktype = locktype; - }else if( locktype==EXCLUSIVE_LOCK ){ - pFile->locktype = PENDING_LOCK; - pLock->locktype = PENDING_LOCK; - } - -end_lock: - leaveMutex(); - OSTRACE4("LOCK %d %s %s\n", pFile->h, locktypeName(locktype), - rc==SQLITE_OK ? "ok" : "failed"); - return rc; -} - -/* -** Lower the locking level on file descriptor pFile 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. -*/ -static int unixUnlock(sqlite3_file *id, int locktype){ - struct lockInfo *pLock; - struct flock lock; - int rc = SQLITE_OK; - unixFile *pFile = (unixFile*)id; - - assert( pFile ); - OSTRACE7("UNLOCK %d %d was %d(%d,%d) pid=%d\n", pFile->h, locktype, - pFile->locktype, pFile->pLock->locktype, pFile->pLock->cnt, getpid()); - - assert( locktype<=SHARED_LOCK ); - if( pFile->locktype<=locktype ){ - return SQLITE_OK; - } - if( CHECK_THREADID(pFile) ){ - return SQLITE_MISUSE; - } - enterMutex(); - pLock = pFile->pLock; - assert( pLock->cnt!=0 ); - if( pFile->locktype>SHARED_LOCK ){ - assert( pLock->locktype==pFile->locktype ); - if( locktype==SHARED_LOCK ){ - lock.l_type = F_RDLCK; - lock.l_whence = SEEK_SET; - lock.l_start = SHARED_FIRST; - lock.l_len = SHARED_SIZE; - if( fcntl(pFile->h, F_SETLK, &lock)==(-1) ){ - /* This should never happen */ - rc = SQLITE_IOERR_RDLOCK; - } - } - lock.l_type = F_UNLCK; - lock.l_whence = SEEK_SET; - lock.l_start = PENDING_BYTE; - lock.l_len = 2L; assert( PENDING_BYTE+1==RESERVED_BYTE ); - if( fcntl(pFile->h, F_SETLK, &lock)!=(-1) ){ - pLock->locktype = SHARED_LOCK; - }else{ - rc = SQLITE_IOERR_UNLOCK; /* This should never happen */ - } - } - if( locktype==NO_LOCK ){ - struct openCnt *pOpen; - - /* Decrement the shared lock counter. Release the lock using an - ** OS call only when all threads in this same process have released - ** the lock. - */ - pLock->cnt--; - if( pLock->cnt==0 ){ - lock.l_type = F_UNLCK; - lock.l_whence = SEEK_SET; - lock.l_start = lock.l_len = 0L; - if( fcntl(pFile->h, F_SETLK, &lock)!=(-1) ){ - pLock->locktype = NO_LOCK; - }else{ - rc = SQLITE_IOERR_UNLOCK; /* This should never happen */ - } - } - - /* Decrement the count of locks against this same file. When the - ** count reaches zero, close any other file descriptors whose close - ** was deferred because of outstanding locks. - */ - pOpen = pFile->pOpen; - pOpen->nLock--; - assert( pOpen->nLock>=0 ); - if( pOpen->nLock==0 && pOpen->nPending>0 ){ - int i; - for(i=0; inPending; i++){ - close(pOpen->aPending[i]); - } - free(pOpen->aPending); - pOpen->nPending = 0; - pOpen->aPending = 0; - } - } - leaveMutex(); - pFile->locktype = locktype; - return rc; -} - -/* -** Close a file. -*/ -static int unixClose(sqlite3_file *id){ - unixFile *pFile = (unixFile *)id; - if( !pFile ) return SQLITE_OK; - unixUnlock(id, NO_LOCK); - if( pFile->dirfd>=0 ) close(pFile->dirfd); - pFile->dirfd = -1; - enterMutex(); - - if( pFile->pOpen->nLock ){ - /* If there are outstanding locks, do not actually close the file just - ** yet because that would clear those locks. Instead, add the file - ** descriptor to pOpen->aPending. It will be automatically closed when - ** the last lock is cleared. - */ - int *aNew; - struct openCnt *pOpen = pFile->pOpen; - aNew = realloc( pOpen->aPending, (pOpen->nPending+1)*sizeof(int) ); - if( aNew==0 ){ - /* If a malloc fails, just leak the file descriptor */ - }else{ - pOpen->aPending = aNew; - pOpen->aPending[pOpen->nPending] = pFile->h; - pOpen->nPending++; - } - }else{ - /* There are no outstanding locks so we can close the file immediately */ - close(pFile->h); - } - releaseLockInfo(pFile->pLock); - releaseOpenCnt(pFile->pOpen); - - leaveMutex(); - OSTRACE2("CLOSE %-3d\n", pFile->h); - OpenCounter(-1); - memset(pFile, 0, sizeof(unixFile)); - return SQLITE_OK; -} - - -#ifdef SQLITE_ENABLE_LOCKING_STYLE -#pragma mark AFP Support - -/* - ** The afpLockingContext structure contains all afp lock specific state - */ -typedef struct afpLockingContext afpLockingContext; -struct afpLockingContext { - unsigned long long sharedLockByte; - char *filePath; -}; - -struct ByteRangeLockPB2 -{ - unsigned long long offset; /* offset to first byte to lock */ - unsigned long long length; /* nbr of bytes to lock */ - unsigned long long retRangeStart; /* nbr of 1st byte locked if successful */ - unsigned char unLockFlag; /* 1 = unlock, 0 = lock */ - unsigned char startEndFlag; /* 1=rel to end of fork, 0=rel to start */ - int fd; /* file desc to assoc this lock with */ -}; - -#define afpfsByteRangeLock2FSCTL _IOWR('z', 23, struct ByteRangeLockPB2) - -/* -** Return 0 on success, 1 on failure. To match the behavior of the -** normal posix file locking (used in unixLock for example), we should -** provide 'richer' return codes - specifically to differentiate between -** 'file busy' and 'file system error' results. -*/ -static int _AFPFSSetLock( - const char *path, - int fd, - unsigned long long offset, - unsigned long long length, - int setLockFlag -){ - struct ByteRangeLockPB2 pb; - int err; - - pb.unLockFlag = setLockFlag ? 0 : 1; - pb.startEndFlag = 0; - pb.offset = offset; - pb.length = length; - pb.fd = fd; - OSTRACE5("AFPLOCK setting lock %s for %d in range %llx:%llx\n", - (setLockFlag?"ON":"OFF"), fd, offset, length); - err = fsctl(path, afpfsByteRangeLock2FSCTL, &pb, 0); - if ( err==-1 ) { - OSTRACE4("AFPLOCK failed to fsctl() '%s' %d %s\n", path, errno, - strerror(errno)); - return 1; /* error */ - } else { - return 0; - } -} - -/* - ** 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. If the file is unlocked or holds only SHARED locks, then - ** return zero. - */ -static int afpUnixCheckReservedLock(sqlite3_file *id){ - int r = 0; - unixFile *pFile = (unixFile*)id; - - assert( pFile ); - afpLockingContext *context = (afpLockingContext *) pFile->lockingContext; - - /* Check if a thread in this process holds such a lock */ - if( pFile->locktype>SHARED_LOCK ){ - r = 1; - } - - /* Otherwise see if some other process holds it. - */ - if ( !r ) { - /* lock the byte */ - int failed = _AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1,1); - if (failed) { - /* if we failed to get the lock then someone else must have it */ - r = 1; - } else { - /* if we succeeded in taking the reserved lock, unlock it to restore - ** the original state */ - _AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1, 0); - } - } - OSTRACE3("TEST WR-LOCK %d %d\n", pFile->h, r); - - return r; -} - -/* AFP-style locking following the behavior of unixLock, see the unixLock -** function comments for details of lock management. */ -static int afpUnixLock(sqlite3_file *id, int locktype) -{ - int rc = SQLITE_OK; - unixFile *pFile = (unixFile*)id; - afpLockingContext *context = (afpLockingContext *) pFile->lockingContext; - int gotPendingLock = 0; - - assert( pFile ); - OSTRACE5("LOCK %d %s was %s pid=%d\n", pFile->h, - locktypeName(locktype), locktypeName(pFile->locktype), getpid()); - /* If there is already a lock of this type or more restrictive on the - ** unixFile, do nothing. Don't use the afp_end_lock: exit path, as - ** enterMutex() hasn't been called yet. - */ - if( pFile->locktype>=locktype ){ - OSTRACE3("LOCK %d %s ok (already held)\n", pFile->h, - locktypeName(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 ); - - /* This mutex is needed because pFile->pLock is shared across threads - */ - enterMutex(); - - /* Make sure the current thread owns the pFile. - */ - rc = transferOwnership(pFile); - if( rc!=SQLITE_OK ){ - leaveMutex(); - return rc; - } - - /* A PENDING lock is needed before acquiring a SHARED lock and before - ** acquiring an EXCLUSIVE lock. For the SHARED lock, the PENDING will - ** be released. - */ - if( locktype==SHARED_LOCK - || (locktype==EXCLUSIVE_LOCK && pFile->locktypefilePath, pFile->h, - PENDING_BYTE, 1, 1); - if (failed) { - rc = SQLITE_BUSY; - goto afp_end_lock; - } - } - - /* If control gets to this point, then actually go ahead and make - ** operating system calls for the specified lock. - */ - if( locktype==SHARED_LOCK ){ - int lk, failed; - int tries = 0; - - /* Now get the read-lock */ - /* note that the quality of the randomness doesn't matter that much */ - lk = random(); - context->sharedLockByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1); - failed = _AFPFSSetLock(context->filePath, pFile->h, - SHARED_FIRST+context->sharedLockByte, 1, 1); - - /* Drop the temporary PENDING lock */ - if (_AFPFSSetLock(context->filePath, pFile->h, PENDING_BYTE, 1, 0)) { - rc = SQLITE_IOERR_UNLOCK; /* This should never happen */ - goto afp_end_lock; - } - - if( failed ){ - rc = SQLITE_BUSY; - } else { - pFile->locktype = SHARED_LOCK; - } - }else{ - /* The request was for a RESERVED or EXCLUSIVE lock. It is - ** assumed that there is a SHARED or greater lock on the file - ** already. - */ - int failed = 0; - assert( 0!=pFile->locktype ); - if (locktype >= RESERVED_LOCK && pFile->locktype < RESERVED_LOCK) { - /* Acquire a RESERVED lock */ - failed = _AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1,1); - } - if (!failed && locktype == EXCLUSIVE_LOCK) { - /* Acquire an EXCLUSIVE lock */ - - /* Remove the shared lock before trying the range. we'll need to - ** reestablish the shared lock if we can't get the afpUnixUnlock - */ - if (!_AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST + - context->sharedLockByte, 1, 0)) { - /* now attemmpt to get the exclusive lock range */ - failed = _AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST, - SHARED_SIZE, 1); - if (failed && _AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST + - context->sharedLockByte, 1, 1)) { - rc = SQLITE_IOERR_RDLOCK; /* this should never happen */ - } - } else { - /* */ - rc = SQLITE_IOERR_UNLOCK; /* this should never happen */ - } - } - if( failed && rc == SQLITE_OK){ - rc = SQLITE_BUSY; - } - } - - if( rc==SQLITE_OK ){ - pFile->locktype = locktype; - }else if( locktype==EXCLUSIVE_LOCK ){ - pFile->locktype = PENDING_LOCK; - } - -afp_end_lock: - leaveMutex(); - OSTRACE4("LOCK %d %s %s\n", pFile->h, locktypeName(locktype), - rc==SQLITE_OK ? "ok" : "failed"); - return rc; -} - -/* - ** Lower the locking level on file descriptor pFile 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. - */ -static int afpUnixUnlock(sqlite3_file *id, int locktype) { - struct flock lock; - int rc = SQLITE_OK; - unixFile *pFile = (unixFile*)id; - afpLockingContext *context = (afpLockingContext *) pFile->lockingContext; - - assert( pFile ); - OSTRACE5("UNLOCK %d %d was %d pid=%d\n", pFile->h, locktype, - pFile->locktype, getpid()); - - assert( locktype<=SHARED_LOCK ); - if( pFile->locktype<=locktype ){ - return SQLITE_OK; - } - if( CHECK_THREADID(pFile) ){ - return SQLITE_MISUSE; - } - enterMutex(); - if( pFile->locktype>SHARED_LOCK ){ - if( locktype==SHARED_LOCK ){ - int failed = 0; - - /* unlock the exclusive range - then re-establish the shared lock */ - if (pFile->locktype==EXCLUSIVE_LOCK) { - failed = _AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST, - SHARED_SIZE, 0); - if (!failed) { - /* successfully removed the exclusive lock */ - if (_AFPFSSetLock(context->filePath, pFile->h, SHARED_FIRST+ - context->sharedLockByte, 1, 1)) { - /* failed to re-establish our shared lock */ - rc = SQLITE_IOERR_RDLOCK; /* This should never happen */ - } - } else { - /* This should never happen - failed to unlock the exclusive range */ - rc = SQLITE_IOERR_UNLOCK; - } - } - } - if (rc == SQLITE_OK && pFile->locktype>=PENDING_LOCK) { - if (_AFPFSSetLock(context->filePath, pFile->h, PENDING_BYTE, 1, 0)){ - /* failed to release the pending lock */ - rc = SQLITE_IOERR_UNLOCK; /* This should never happen */ - } - } - if (rc == SQLITE_OK && pFile->locktype>=RESERVED_LOCK) { - if (_AFPFSSetLock(context->filePath, pFile->h, RESERVED_BYTE, 1, 0)) { - /* failed to release the reserved lock */ - rc = SQLITE_IOERR_UNLOCK; /* This should never happen */ - } - } - } - if( locktype==NO_LOCK ){ - int failed = _AFPFSSetLock(context->filePath, pFile->h, - SHARED_FIRST + context->sharedLockByte, 1, 0); - if (failed) { - rc = SQLITE_IOERR_UNLOCK; /* This should never happen */ - } - } - if (rc == SQLITE_OK) - pFile->locktype = locktype; - leaveMutex(); - return rc; -} - -/* - ** Close a file & cleanup AFP specific locking context - */ -static int afpUnixClose(sqlite3_file *id) { - unixFile *pFile = (unixFile*)pId; - - if( !pFile ) return SQLITE_OK; - afpUnixUnlock(*pId, NO_LOCK); - /* free the AFP locking structure */ - if (pFile->lockingContext != NULL) { - if (((afpLockingContext *)pFile->lockingContext)->filePath != NULL) - sqlite3_free(((afpLockingContext*)pFile->lockingContext)->filePath); - sqlite3_free(pFile->lockingContext); - } - - if( pFile->dirfd>=0 ) close(pFile->dirfd); - pFile->dirfd = -1; - close(pFile->h); - OSTRACE2("CLOSE %-3d\n", pFile->h); - OpenCounter(-1); - return SQLITE_OK; -} - - -#pragma mark flock() style locking - -/* - ** The flockLockingContext is not used - */ -typedef void flockLockingContext; - -static int flockUnixCheckReservedLock(sqlite3_file *id) { - unixFile *pFile = (unixFile*)id; - - if (pFile->locktype == RESERVED_LOCK) { - return 1; /* already have a reserved lock */ - } else { - /* attempt to get the lock */ - int rc = flock(pFile->h, LOCK_EX | LOCK_NB); - if (!rc) { - /* got the lock, unlock it */ - flock(pFile->h, LOCK_UN); - return 0; /* no one has it reserved */ - } - return 1; /* someone else might have it reserved */ - } -} - -static int flockUnixLock(sqlite3_file *id, int locktype) { - unixFile *pFile = (unixFile*)id; - - /* if we already have a lock, it is exclusive. - ** Just adjust level and punt on outta here. */ - if (pFile->locktype > NO_LOCK) { - pFile->locktype = locktype; - return SQLITE_OK; - } - - /* grab an exclusive lock */ - int rc = flock(pFile->h, LOCK_EX | LOCK_NB); - if (rc) { - /* didn't get, must be busy */ - return SQLITE_BUSY; - } else { - /* got it, set the type and return ok */ - pFile->locktype = locktype; - return SQLITE_OK; - } -} - -static int flockUnixUnlock(sqlite3_file *id, int locktype) { - unixFile *pFile = (unixFile*)id; - - assert( locktype<=SHARED_LOCK ); - - /* no-op if possible */ - if( pFile->locktype==locktype ){ - return SQLITE_OK; - } - - /* shared can just be set because we always have an exclusive */ - if (locktype==SHARED_LOCK) { - pFile->locktype = locktype; - return SQLITE_OK; - } - - /* no, really, unlock. */ - int rc = flock(pFile->h, LOCK_UN); - if (rc) - return SQLITE_IOERR_UNLOCK; - else { - pFile->locktype = NO_LOCK; - return SQLITE_OK; - } -} - -/* - ** Close a file. - */ -static int flockUnixClose(sqlite3_file *pId) { - unixFile *pFile = (unixFile*)*pId; - - if( !pFile ) return SQLITE_OK; - flockUnixUnlock(*pId, NO_LOCK); - - if( pFile->dirfd>=0 ) close(pFile->dirfd); - pFile->dirfd = -1; - enterMutex(); - - close(pFile->h); - leaveMutex(); - OSTRACE2("CLOSE %-3d\n", pFile->h); - OpenCounter(-1); - return SQLITE_OK; -} - -#pragma mark Old-School .lock file based locking - -/* - ** The dotlockLockingContext structure contains all dotlock (.lock) lock - ** specific state - */ -typedef struct dotlockLockingContext dotlockLockingContext; -struct dotlockLockingContext { - char *lockPath; -}; - - -static int dotlockUnixCheckReservedLock(sqlite3_file *id) { - unixFile *pFile = (unixFile*)id; - dotlockLockingContext *context = - (dotlockLockingContext *) pFile->lockingContext; - - if (pFile->locktype == RESERVED_LOCK) { - return 1; /* already have a reserved lock */ - } else { - struct stat statBuf; - if (lstat(context->lockPath,&statBuf) == 0) - /* file exists, someone else has the lock */ - return 1; - else - /* file does not exist, we could have it if we want it */ - return 0; - } -} - -static int dotlockUnixLock(sqlite3_file *id, int locktype) { - unixFile *pFile = (unixFile*)id; - dotlockLockingContext *context = - (dotlockLockingContext *) pFile->lockingContext; - - /* if we already have a lock, it is exclusive. - ** Just adjust level and punt on outta here. */ - if (pFile->locktype > NO_LOCK) { - pFile->locktype = locktype; - - /* Always update the timestamp on the old file */ - utimes(context->lockPath,NULL); - return SQLITE_OK; - } - - /* check to see if lock file already exists */ - struct stat statBuf; - if (lstat(context->lockPath,&statBuf) == 0){ - return SQLITE_BUSY; /* it does, busy */ - } - - /* grab an exclusive lock */ - int fd = open(context->lockPath,O_RDONLY|O_CREAT|O_EXCL,0600); - if (fd < 0) { - /* failed to open/create the file, someone else may have stolen the lock */ - return SQLITE_BUSY; - } - close(fd); - - /* got it, set the type and return ok */ - pFile->locktype = locktype; - return SQLITE_OK; -} - -static int dotlockUnixUnlock(sqlite3_file *id, int locktype) { - unixFile *pFile = (unixFile*)id; - dotlockLockingContext *context = - (dotlockLockingContext *) pFile->lockingContext; - - assert( locktype<=SHARED_LOCK ); - - /* no-op if possible */ - if( pFile->locktype==locktype ){ - return SQLITE_OK; - } - - /* shared can just be set because we always have an exclusive */ - if (locktype==SHARED_LOCK) { - pFile->locktype = locktype; - return SQLITE_OK; - } - - /* no, really, unlock. */ - unlink(context->lockPath); - pFile->locktype = NO_LOCK; - return SQLITE_OK; -} - -/* - ** Close a file. - */ -static int dotlockUnixClose(sqlite3_file *id) { - unixFile *pFile = (unixFile*)id; - - if( !pFile ) return SQLITE_OK; - dotlockUnixUnlock(*pId, NO_LOCK); - /* free the dotlock locking structure */ - if (pFile->lockingContext != NULL) { - if (((dotlockLockingContext *)pFile->lockingContext)->lockPath != NULL) - sqlite3_free( ( (dotlockLockingContext *) - pFile->lockingContext)->lockPath); - sqlite3_free(pFile->lockingContext); - } - - if( pFile->dirfd>=0 ) close(pFile->dirfd); - pFile->dirfd = -1; - enterMutex(); - - close(pFile->h); - - leaveMutex(); - OSTRACE2("CLOSE %-3d\n", pFile->h); - OpenCounter(-1); - return SQLITE_OK; -} - - -#pragma mark No locking - -/* - ** The nolockLockingContext is void - */ -typedef void nolockLockingContext; - -static int nolockUnixCheckReservedLock(sqlite3_file *id) { - return 0; -} - -static int nolockUnixLock(sqlite3_file *id, int locktype) { - return SQLITE_OK; -} - -static int nolockUnixUnlock(sqlite3_file *id, int locktype) { - return SQLITE_OK; -} - -/* - ** Close a file. - */ -static int nolockUnixClose(sqlite3_file *id) { - unixFile *pFile = (unixFile*)id; - - if( !pFile ) return SQLITE_OK; - if( pFile->dirfd>=0 ) close(pFile->dirfd); - pFile->dirfd = -1; - enterMutex(); - - close(pFile->h); - - leaveMutex(); - OSTRACE2("CLOSE %-3d\n", pFile->h); - OpenCounter(-1); - return SQLITE_OK; -} - -#endif /* SQLITE_ENABLE_LOCKING_STYLE */ - - -/* -** Information and control of an open file handle. -*/ -static int unixFileControl(sqlite3_file *id, int op, void *pArg){ - switch( op ){ - case SQLITE_FCNTL_LOCKSTATE: { - *(int*)pArg = ((unixFile*)id)->locktype; - return SQLITE_OK; - } - } - return SQLITE_ERROR; -} - -/* -** Return the sector size in bytes of the underlying block device for -** the specified file. This is almost always 512 bytes, but may be -** larger for some devices. -** -** SQLite code assumes this function cannot fail. It also assumes that -** if two files are created in the same file-system directory (i.e. -** a database and it's journal file) that the sector size will be the -** same for both. -*/ -static int unixSectorSize(sqlite3_file *id){ - return SQLITE_DEFAULT_SECTOR_SIZE; -} - -/* -** Return the device characteristics for the file. This is always 0. -*/ -static int unixDeviceCharacteristics(sqlite3_file *id){ - return 0; -} - -/* -** This vector defines all the methods that can operate on an sqlite3_file -** for unix. -*/ -static const sqlite3_io_methods sqlite3UnixIoMethod = { - 1, /* iVersion */ - unixClose, - unixRead, - unixWrite, - unixTruncate, - unixSync, - unixFileSize, - unixLock, - unixUnlock, - unixCheckReservedLock, - unixFileControl, - unixSectorSize, - unixDeviceCharacteristics -}; - -#ifdef SQLITE_ENABLE_LOCKING_STYLE -/* -** This vector defines all the methods that can operate on an sqlite3_file -** for unix with AFP style file locking. -*/ -static const sqlite3_io_methods sqlite3AFPLockingUnixIoMethod = { - 1, /* iVersion */ - unixClose, - unixRead, - unixWrite, - unixTruncate, - unixSync, - unixFileSize, - afpUnixLock, - afpUnixUnlock, - afpUnixCheckReservedLock, - unixFileControl, - unixSectorSize, - unixDeviceCharacteristics -}; - -/* -** This vector defines all the methods that can operate on an sqlite3_file -** for unix with flock() style file locking. -*/ -static const sqlite3_io_methods sqlite3FlockLockingUnixIoMethod = { - 1, /* iVersion */ - flockUnixClose, - unixRead, - unixWrite, - unixTruncate, - unixSync, - unixFileSize, - flockUnixLock, - flockUnixUnlock, - flockUnixCheckReservedLock, - unixFileControl, - unixSectorSize, - unixDeviceCharacteristics -}; - -/* -** This vector defines all the methods that can operate on an sqlite3_file -** for unix with dotlock style file locking. -*/ -static const sqlite3_io_methods sqlite3DotlockLockingUnixIoMethod = { - 1, /* iVersion */ - dotlockUnixClose, - unixRead, - unixWrite, - unixTruncate, - unixSync, - unixFileSize, - dotlockUnixLock, - dotlockUnixUnlock, - dotlockUnixCheckReservedLock, - unixFileControl, - unixSectorSize, - unixDeviceCharacteristics -}; - -/* -** This vector defines all the methods that can operate on an sqlite3_file -** for unix with dotlock style file locking. -*/ -static const sqlite3_io_methods sqlite3NolockLockingUnixIoMethod = { - 1, /* iVersion */ - nolockUnixClose, - unixRead, - unixWrite, - unixTruncate, - unixSync, - unixFileSize, - nolockUnixLock, - nolockUnixUnlock, - nolockUnixCheckReservedLock, - unixFileControl, - unixSectorSize, - unixDeviceCharacteristics -}; - -#endif /* SQLITE_ENABLE_LOCKING_STYLE */ - -/* -** Allocate memory for a new unixFile and initialize that unixFile. -** Write a pointer to the new unixFile into *pId. -** If we run out of memory, close the file and return an error. -*/ -#ifdef SQLITE_ENABLE_LOCKING_STYLE -/* -** When locking extensions are enabled, the filepath and locking style -** are needed to determine the unixFile pMethod to use for locking operations. -** The locking-style specific lockingContext data structure is created -** and assigned here also. -*/ -static int fillInUnixFile( - int h, /* Open file descriptor of file being opened */ - int dirfd, /* Directory file descriptor */ - sqlite3_file *pId, /* Write completed initialization here */ - const char *zFilename, /* Name of the file being opened */ -){ - sqlite3LockingStyle lockingStyle; - unixFile *pNew = (unixFile *)pId; - int rc; - - memset(pNew, 0, sizeof(unixFile)); - lockingStyle = sqlite3DetectLockingStyle(zFilename, h); - if ( lockingStyle == posixLockingStyle ) { - enterMutex(); - rc = findLockInfo(h, &pNew->pLock, &pNew->pOpen); - leaveMutex(); - if( rc ){ - close(h); - unlink(zFilename); - return SQLITE_NOMEM; - } - } else { - /* pLock and pOpen are only used for posix advisory locking */ - pNew->pLock = NULL; - pNew->pOpen = NULL; - } - pNew->dirfd = -1; - pNew->h = h; - SET_THREADID(pNew); - pNew = sqlite3_malloc( sizeof(unixFile) ); - if( pNew==0 ){ - close(h); - enterMutex(); - releaseLockInfo(pNew->pLock); - releaseOpenCnt(pNew->pOpen); - leaveMutex(); - return SQLITE_NOMEM; - }else{ - switch(lockingStyle) { - case afpLockingStyle: { - /* afp locking uses the file path so it needs to be included in - ** the afpLockingContext */ - int nFilename; - pNew->pMethod = &sqlite3AFPLockingUnixIoMethod; - pNew->lockingContext = - sqlite3_malloc(sizeof(afpLockingContext)); - nFilename = strlen(zFilename)+1; - ((afpLockingContext *)pNew->lockingContext)->filePath = - sqlite3_malloc(nFilename); - memcpy(((afpLockingContext *)pNew->lockingContext)->filePath, - zFilename, nFilename); - srandomdev(); - break; - } - case flockLockingStyle: - /* flock locking doesn't need additional lockingContext information */ - pNew->pMethod = &sqlite3FlockLockingUnixIoMethod; - break; - case dotlockLockingStyle: { - /* dotlock locking uses the file path so it needs to be included in - ** the dotlockLockingContext */ - int nFilename; - pNew->pMethod = &sqlite3DotlockLockingUnixIoMethod; - pNew->lockingContext = sqlite3_malloc( - sizeof(dotlockLockingContext)); - nFilename = strlen(zFilename) + 6; - ((dotlockLockingContext *)pNew->lockingContext)->lockPath = - sqlite3_malloc( nFilename ); - sqlite3_snprintf(nFilename, - ((dotlockLockingContext *)pNew->lockingContext)->lockPath, - "%s.lock", zFilename); - break; - } - case posixLockingStyle: - /* posix locking doesn't need additional lockingContext information */ - pNew->pMethod = &sqlite3UnixIoMethod; - break; - case noLockingStyle: - case unsupportedLockingStyle: - default: - pNew->pMethod = &sqlite3NolockLockingUnixIoMethod; - } - OpenCounter(+1); - return SQLITE_OK; - } -} -#else /* SQLITE_ENABLE_LOCKING_STYLE */ -static int fillInUnixFile( - int h, /* Open file descriptor on file being opened */ - int dirfd, - sqlite3_file *pId, /* Write to the unixFile structure here */ - const char *zFilename /* Name of the file being opened */ -){ - unixFile *pNew = (unixFile *)pId; - int rc; - -#ifdef FD_CLOEXEC - fcntl(h, F_SETFD, fcntl(h, F_GETFD, 0) | FD_CLOEXEC); -#endif - - enterMutex(); - rc = findLockInfo(h, &pNew->pLock, &pNew->pOpen); - leaveMutex(); - if( rc ){ - close(h); - return SQLITE_NOMEM; - } - - OSTRACE3("OPEN %-3d %s\n", h, zFilename); - pNew->dirfd = -1; - pNew->h = h; - pNew->dirfd = dirfd; - SET_THREADID(pNew); - - pNew->pMethod = &sqlite3UnixIoMethod; - OpenCounter(+1); - return SQLITE_OK; -} -#endif /* SQLITE_ENABLE_LOCKING_STYLE */ - -/* -** Open a file descriptor to the directory containing file zFilename. -** If successful, *pFd is set to the opened file descriptor and -** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM -** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined -** value. -** -** If SQLITE_OK is returned, the caller is responsible for closing -** the file descriptor *pFd using close(). -*/ -static int openDirectory(const char *zFilename, int *pFd){ - int ii; - int fd = -1; - char zDirname[MAX_PATHNAME+1]; - - sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename); - for(ii=strlen(zDirname); ii>=0 && zDirname[ii]!='/'; ii--); - if( ii>0 ){ - zDirname[ii] = '\0'; - fd = open(zDirname, O_RDONLY|O_BINARY, 0); - if( fd>=0 ){ -#ifdef FD_CLOEXEC - fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC); -#endif - OSTRACE3("OPENDIR %-3d %s\n", fd, zDirname); - } - } - *pFd = fd; - return (fd>=0?SQLITE_OK:SQLITE_CANTOPEN); -} - -/* -** Open the file zPath. -** -** Previously, the SQLite OS layer used three functions in place of this -** one: -** -** sqlite3OsOpenReadWrite(); -** sqlite3OsOpenReadOnly(); -** sqlite3OsOpenExclusive(); -** -** These calls correspond to the following combinations of flags: -** -** ReadWrite() -> (READWRITE | CREATE) -** ReadOnly() -> (READONLY) -** OpenExclusive() -> (READWRITE | CREATE | EXCLUSIVE) -** -** The old OpenExclusive() accepted a boolean argument - "delFlag". If -** true, the file was configured to be automatically deleted when the -** file handle closed. To achieve the same effect using this new -** interface, add the DELETEONCLOSE flag to those specified above for -** OpenExclusive(). -*/ -static int unixOpen( - sqlite3_vfs *pVfs, - const char *zPath, - sqlite3_file *pFile, - int flags, - int *pOutFlags -){ - int fd = 0; /* File descriptor returned by open() */ - int dirfd = -1; /* Directory file descriptor */ - int oflags = 0; /* Flags to pass to open() */ - int eType = flags&0xFFFFFF00; /* Type of file to open */ - - int isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE); - int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE); - int isCreate = (flags & SQLITE_OPEN_CREATE); - int isReadonly = (flags & SQLITE_OPEN_READONLY); - int isReadWrite = (flags & SQLITE_OPEN_READWRITE); - - /* If creating a master or main-file journal, this function will open - ** a file-descriptor on the directory too. The first time unixSync() - ** is called the directory file descriptor will be fsync()ed and close()d. - */ - int isOpenDirectory = (isCreate && - (eType==SQLITE_OPEN_MASTER_JOURNAL || eType==SQLITE_OPEN_MAIN_JOURNAL) - ); - - /* Check the following statements are true: - ** - ** (a) Exactly one of the READWRITE and READONLY flags must be set, and - ** (b) if CREATE is set, then READWRITE must also be set, and - ** (c) if EXCLUSIVE is set, then CREATE must also be set. - ** (d) if DELETEONCLOSE is set, then CREATE must also be set. - */ - assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly)); - assert(isCreate==0 || isReadWrite); - assert(isExclusive==0 || isCreate); - assert(isDelete==0 || isCreate); - - - /* The main DB, main journal, and master journal are never automatically - ** deleted - */ - assert( eType!=SQLITE_OPEN_MAIN_DB || !isDelete ); - assert( eType!=SQLITE_OPEN_MAIN_JOURNAL || !isDelete ); - assert( eType!=SQLITE_OPEN_MASTER_JOURNAL || !isDelete ); - - /* Assert that the upper layer has set one of the "file-type" flags. */ - assert( eType==SQLITE_OPEN_MAIN_DB || eType==SQLITE_OPEN_TEMP_DB - || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL - || eType==SQLITE_OPEN_SUBJOURNAL || eType==SQLITE_OPEN_MASTER_JOURNAL - || eType==SQLITE_OPEN_TRANSIENT_DB - ); - - if( isReadonly ) oflags |= O_RDONLY; - if( isReadWrite ) oflags |= O_RDWR; - if( isCreate ) oflags |= O_CREAT; - if( isExclusive ) oflags |= (O_EXCL|O_NOFOLLOW); - oflags |= (O_LARGEFILE|O_BINARY); - - memset(pFile, 0, sizeof(unixFile)); - fd = open(zPath, oflags, isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS); - if( fd<0 && errno!=EISDIR && isReadWrite && !isExclusive ){ - /* Failed to open the file for read/write access. Try read-only. */ - flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE); - flags |= SQLITE_OPEN_READONLY; - return unixOpen(pVfs, zPath, pFile, flags, pOutFlags); - } - if( fd<0 ){ - return SQLITE_CANTOPEN; - } - if( isDelete ){ - unlink(zPath); - } - if( pOutFlags ){ - *pOutFlags = flags; - } - - assert(fd!=0); - if( isOpenDirectory ){ - int rc = openDirectory(zPath, &dirfd); - if( rc!=SQLITE_OK ){ - close(fd); - return rc; - } - } - return fillInUnixFile(fd, dirfd, pFile, zPath); -} - -/* -** Delete the file at zPath. If the dirSync argument is true, fsync() -** the directory after deleting the file. -*/ -static int unixDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){ - int rc = SQLITE_OK; - SimulateIOError(return SQLITE_IOERR_DELETE); - unlink(zPath); - if( dirSync ){ - int fd; - rc = openDirectory(zPath, &fd); - if( rc==SQLITE_OK ){ - if( fsync(fd) ){ - rc = SQLITE_IOERR_DIR_FSYNC; - } - close(fd); - } - } - return rc; -} - -/* -** Test the existance of or access permissions of file zPath. The -** test performed depends on the value of flags: -** -** SQLITE_ACCESS_EXISTS: Return 1 if the file exists -** SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable. -** SQLITE_ACCESS_READONLY: Return 1 if the file is readable. -** -** Otherwise return 0. -*/ -static int unixAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){ - int amode = 0; - switch( flags ){ - case SQLITE_ACCESS_EXISTS: - amode = F_OK; - break; - case SQLITE_ACCESS_READWRITE: - amode = W_OK|R_OK; - break; - case SQLITE_ACCESS_READ: - amode = R_OK; - break; - - default: - assert(!"Invalid flags argument"); - } - return (access(zPath, amode)==0); -} - -/* -** Create a temporary file name in zBuf. zBuf must be allocated -** by the calling process and must be big enough to hold at least -** pVfs->mxPathname bytes. -*/ -static int unixGetTempname(sqlite3_vfs *pVfs, int nBuf, char *zBuf){ - static const char *azDirs[] = { - 0, - "/var/tmp", - "/usr/tmp", - "/tmp", - ".", - }; - static const unsigned char zChars[] = - "abcdefghijklmnopqrstuvwxyz" - "ABCDEFGHIJKLMNOPQRSTUVWXYZ" - "0123456789"; - int i, j; - struct stat buf; - const char *zDir = "."; - - /* It's odd to simulate an io-error here, but really this is just - ** using the io-error infrastructure to test that SQLite handles this - ** function failing. - */ - SimulateIOError( return SQLITE_ERROR ); - - azDirs[0] = sqlite3_temp_directory; - for(i=0; imxPathname==MAX_PATHNAME ); - assert( nBuf>=MAX_PATHNAME ); - sqlite3_snprintf(MAX_PATHNAME-17, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX, zDir); - 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; - }while( access(zBuf,0)==0 ); - return SQLITE_OK; -} - - -/* -** Turn a relative pathname into a full pathname. The relative path -** is stored as a nul-terminated string in the buffer pointed to by -** zPath. -** -** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes -** (in this case, MAX_PATHNAME bytes). The full-path is written to -** this buffer before returning. -*/ -static int unixFullPathname( - sqlite3_vfs *pVfs, /* Pointer to vfs object */ - const char *zPath, /* Possibly relative input path */ - int nOut, /* Size of output buffer in bytes */ - char *zOut /* Output buffer */ -){ - - /* It's odd to simulate an io-error here, but really this is just - ** using the io-error infrastructure to test that SQLite handles this - ** function failing. This function could fail if, for example, the - ** current working directly has been unlinked. - */ - SimulateIOError( return SQLITE_ERROR ); - - assert( pVfs->mxPathname==MAX_PATHNAME ); - zOut[MAX_PATHNAME-1] = '\0'; - if( zPath[0]=='/' ){ - sqlite3_snprintf(MAX_PATHNAME, zOut, "%s", zPath); - }else{ - int nCwd; - if( getcwd(zOut, MAX_PATHNAME-1)==0 ){ - return SQLITE_CANTOPEN; - } - nCwd = strlen(zOut); - sqlite3_snprintf(MAX_PATHNAME-nCwd, &zOut[nCwd], "/%s", zPath); - } - return SQLITE_OK; - -#if 0 - /* - ** Remove "/./" path elements and convert "/A/./" path elements - ** to just "/". - */ - if( zFull ){ - int i, j; - for(i=j=0; zFull[i]; i++){ - if( zFull[i]=='/' ){ - if( zFull[i+1]=='/' ) continue; - if( zFull[i+1]=='.' && zFull[i+2]=='/' ){ - i += 1; - continue; - } - if( zFull[i+1]=='.' && zFull[i+2]=='.' && zFull[i+3]=='/' ){ - while( j>0 && zFull[j-1]!='/' ){ j--; } - i += 3; - continue; - } - } - zFull[j++] = zFull[i]; - } - zFull[j] = 0; - } -#endif -} - - -#ifndef SQLITE_OMIT_LOAD_EXTENSION -/* -** Interfaces for opening a shared library, finding entry points -** within the shared library, and closing the shared library. -*/ -#include -static void *unixDlOpen(sqlite3_vfs *pVfs, const char *zFilename){ - return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL); -} - -/* -** SQLite calls this function immediately after a call to unixDlSym() or -** unixDlOpen() fails (returns a null pointer). If a more detailed error -** message is available, it is written to zBufOut. If no error message -** is available, zBufOut is left unmodified and SQLite uses a default -** error message. -*/ -static void unixDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){ - char *zErr; - enterMutex(); - zErr = dlerror(); - if( zErr ){ - sqlite3_snprintf(nBuf, zBufOut, "%s", zErr); - } - leaveMutex(); -} -static void *unixDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){ - return dlsym(pHandle, zSymbol); -} -static void unixDlClose(sqlite3_vfs *pVfs, void *pHandle){ - dlclose(pHandle); -} -#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */ - #define unixDlOpen 0 - #define unixDlError 0 - #define unixDlSym 0 - #define unixDlClose 0 -#endif - -/* -** Write nBuf bytes of random data to the supplied buffer zBuf. -*/ -static int unixRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){ - - assert(nBuf>=(sizeof(time_t)+sizeof(int))); - - /* 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, nBuf); -#if !defined(SQLITE_TEST) - { - int pid, fd; - fd = open("/dev/urandom", O_RDONLY); - if( fd<0 ){ - time_t t; - time(&t); - memcpy(zBuf, &t, sizeof(t)); - pid = getpid(); - memcpy(&zBuf[sizeof(t)], &pid, sizeof(pid)); - }else{ - read(fd, zBuf, nBuf); - close(fd); - } - } -#endif - return SQLITE_OK; -} - - -/* -** Sleep for a little while. Return the amount of time slept. -** The argument is the number of microseconds we want to sleep. -** The return value is the number of microseconds of sleep actually -** requested from the underlying operating system, a number which -** might be greater than or equal to the argument, but not less -** than the argument. -*/ -static int unixSleep(sqlite3_vfs *pVfs, int microseconds){ -#if defined(HAVE_USLEEP) && HAVE_USLEEP - usleep(microseconds); - return microseconds; -#else - int seconds = (microseconds+999999)/1000000; - sleep(seconds); - return seconds*1000000; -#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. -*/ -static int unixCurrentTime(sqlite3_vfs *pVfs, double *prNow){ -#ifdef NO_GETTOD - time_t t; - time(&t); - *prNow = t/86400.0 + 2440587.5; -#else - struct timeval sNow; - gettimeofday(&sNow, 0); - *prNow = 2440587.5 + sNow.tv_sec/86400.0 + sNow.tv_usec/86400000000.0; -#endif -#ifdef SQLITE_TEST - if( sqlite3_current_time ){ - *prNow = sqlite3_current_time/86400.0 + 2440587.5; - } -#endif - return 0; -} - -/* -** Return a pointer to the sqlite3DefaultVfs structure. We use -** a function rather than give the structure global scope because -** some compilers (MSVC) do not allow forward declarations of -** initialized structures. -*/ -sqlite3_vfs *sqlite3OsDefaultVfs(void){ - static sqlite3_vfs unixVfs = { - 1, /* iVersion */ - sizeof(unixFile), /* szOsFile */ - MAX_PATHNAME, /* mxPathname */ - 0, /* pNext */ - "unix", /* zName */ - 0, /* pAppData */ - - unixOpen, /* xOpen */ - unixDelete, /* xDelete */ - unixAccess, /* xAccess */ - unixGetTempname, /* xGetTempName */ - unixFullPathname, /* xFullPathname */ - unixDlOpen, /* xDlOpen */ - unixDlError, /* xDlError */ - unixDlSym, /* xDlSym */ - unixDlClose, /* xDlClose */ - unixRandomness, /* xRandomness */ - unixSleep, /* xSleep */ - unixCurrentTime /* xCurrentTime */ - }; - - return &unixVfs; -} - -#endif /* OS_UNIX */ -- cgit v1.1