diff options
Diffstat (limited to 'ACE/ace/Filecache.cpp')
| -rw-r--r-- | ACE/ace/Filecache.cpp | 751 |
1 files changed, 751 insertions, 0 deletions
diff --git a/ACE/ace/Filecache.cpp b/ACE/ace/Filecache.cpp new file mode 100644 index 00000000000..b76a3255d16 --- /dev/null +++ b/ACE/ace/Filecache.cpp @@ -0,0 +1,751 @@ +// $Id$ + +#include "ace/Filecache.h" +#include "ace/Object_Manager.h" +#include "ace/Log_Msg.h" +#include "ace/ACE.h" +#include "ace/Guard_T.h" +#include "ace/OS_NS_string.h" +#include "ace/OS_NS_time.h" +#include "ace/OS_NS_unistd.h" +#include "ace/OS_NS_fcntl.h" + +ACE_RCSID (ace, + Filecache, + "$Id$") + +#if defined (ACE_WIN32) +// Specifies no sharing flags. +#define R_MASK ACE_DEFAULT_OPEN_PERMS +#define W_MASK 0 +#else +#define R_MASK S_IRUSR|S_IRGRP|S_IROTH +#define W_MASK S_IRUSR|S_IRGRP|S_IROTH|S_IWUSR|S_IWGRP|S_IWOTH +#endif /* ACE_WIN32 */ + +#if defined (ACE_WIN32) +// See if you can get rid of some of these. +#define READ_FLAGS (FILE_FLAG_SEQUENTIAL_SCAN | \ + FILE_FLAG_OVERLAPPED | \ + O_RDONLY) +// static const int RCOPY_FLAGS = (FILE_FLAG_SEQUENTIAL_SCAN | +// O_RDONLY); +#define WRITE_FLAGS (FILE_FLAG_SEQUENTIAL_SCAN | \ + FILE_FLAG_OVERLAPPED | \ + O_RDWR | O_CREAT | O_TRUNC) +// static const int WCOPY_FLAGS = (FILE_FLAG_SEQUENTIAL_SCAN | +// O_RDWR | O_CREAT | O_TRUNC); +#else +#define READ_FLAGS O_RDONLY +// static const int RCOPY_FLAGS = O_RDONLY; +#define WRITE_FLAGS (O_RDWR | O_CREAT | O_TRUNC) +// static const int WCOPY_FLAGS = O_RDWR | O_CREAT | O_TRUNC; +#endif /* ACE_WIN32 */ + +ACE_BEGIN_VERSIONED_NAMESPACE_DECL + +// static data members +ACE_Filecache *ACE_Filecache::cvf_ = 0; + +void +ACE_Filecache_Handle::init (void) +{ + this->file_ = 0; + this->handle_ = ACE_INVALID_HANDLE; +} + +ACE_Filecache_Handle::ACE_Filecache_Handle (void) + : file_ (0), handle_ (0), mapit_ (0) +{ + this->init (); +} + +ACE_Filecache_Handle::ACE_Filecache_Handle (const ACE_TCHAR *filename, + ACE_Filecache_Flag mapit) + : file_ (0), handle_ (0), mapit_ (mapit) +{ + this->init (); + // Fetch the file from the Virtual_Filesystem let the + // Virtual_Filesystem do the work of cache coherency. + + // Filecache will also do the acquire, since it holds the lock at + // that time. + this->file_ = ACE_Filecache::instance ()->fetch (filename, mapit); +} + +ACE_Filecache_Handle::ACE_Filecache_Handle (const ACE_TCHAR *filename, + int size, + ACE_Filecache_Flag mapit) + : file_ (0), handle_ (0), mapit_ (mapit) +{ + this->init (); + + if (size == 0) + ACE_Filecache::instance ()->remove (filename); + else + { + // Since this is being opened for a write, simply create a new + // ACE_Filecache_Object now, and let the destructor add it into CVF + // later + + // Filecache will also do the acquire, since it holds the lock at + // that time. + this->file_ = ACE_Filecache::instance ()->create (filename, size); + } +} + +ACE_Filecache_Handle::~ACE_Filecache_Handle (void) +{ + if (this->handle_ != ACE_INVALID_HANDLE) + // this was dup ()'d + ACE_OS::close (this->handle_); + + ACE_Filecache::instance ()->finish (this->file_); +} + +void * +ACE_Filecache_Handle::address (void) const +{ + return this->file_ == 0 ? 0 : this->file_->address (); +} + +ACE_HANDLE +ACE_Filecache_Handle::handle (void) const +{ + if (this->handle_ == ACE_INVALID_HANDLE && this->file_ != 0) + { + ACE_Filecache_Handle *mutable_this = + const_cast<ACE_Filecache_Handle *> (this); + mutable_this->handle_ = ACE_OS::dup (this->file_->handle ()); + } + return this->handle_; +} + +int +ACE_Filecache_Handle::error (void) const +{ + if (this->file_ == 0) + return -1; + else + return this->file_->error (); +} + +ACE_LOFF_T +ACE_Filecache_Handle::size (void) const +{ + if (this->file_ == 0) + return -1; + else + return this->file_->size (); +} + +// ------------------ +// ACE_Filecache_Hash +// ------------------ + +#define ACE_Filecache_Hash \ + ACE_Hash_Map_Manager_Ex<const ACE_TCHAR *, ACE_Filecache_Object *, ACE_Hash<const ACE_TCHAR *>, ACE_Equal_To<const ACE_TCHAR *>, ACE_Null_Mutex> +#define ACE_Filecache_Hash_Entry \ + ACE_Hash_Map_Entry<const ACE_TCHAR *, ACE_Filecache_Object *> + +template <> +ACE_Filecache_Hash_Entry::ACE_Hash_Map_Entry ( + const ACE_TCHAR *const &ext_id, + ACE_Filecache_Object *const &int_id, + ACE_Filecache_Hash_Entry *next, + ACE_Filecache_Hash_Entry *prev) + : ext_id_ (ext_id + ? ACE_OS::strdup (ext_id) + : ACE_OS::strdup (ACE_LIB_TEXT (""))), + int_id_ (int_id), + next_ (next), + prev_ (prev) +{ +} + +template <> +ACE_Filecache_Hash_Entry::ACE_Hash_Map_Entry (ACE_Filecache_Hash_Entry *next, + ACE_Filecache_Hash_Entry *prev) + : ext_id_ (0), + next_ (next), + prev_ (prev) +{ +} + +template <> +ACE_Filecache_Hash_Entry::~ACE_Hash_Map_Entry (void) +{ + ACE_OS::free ((void *) ext_id_); +} + +// We need these template specializations since KEY is defined as a +// ACE_TCHAR*, which doesn't have a hash() or equal() method defined on it. + +template <> +unsigned long +ACE_Filecache_Hash::hash (const ACE_TCHAR *const &ext_id) +{ + return ACE::hash_pjw (ext_id); +} + +template <> +int +ACE_Filecache_Hash::equal (const ACE_TCHAR *const &id1, + const ACE_TCHAR *const &id2) +{ + return ACE_OS::strcmp (id1, id2) == 0; +} + +#undef ACE_Filecache_Hash +#undef ACE_Filecache_Hash_Entry + + +// ------------- +// ACE_Filecache +// ------------- + +ACE_Filecache * +ACE_Filecache::instance (void) +{ + // Double check locking pattern. + if (ACE_Filecache::cvf_ == 0) + { + ACE_SYNCH_RW_MUTEX &lock = + *ACE_Managed_Object<ACE_SYNCH_RW_MUTEX>::get_preallocated_object + (ACE_Object_Manager::ACE_FILECACHE_LOCK); + ACE_GUARD_RETURN (ACE_SYNCH_RW_MUTEX, ace_mon, lock, 0); + + // @@ James, please check each of the ACE_NEW_RETURN calls to + // make sure that it is safe to return if allocation fails. + if (ACE_Filecache::cvf_ == 0) + ACE_NEW_RETURN (ACE_Filecache::cvf_, + ACE_Filecache, + 0); + } + + return ACE_Filecache::cvf_; +} + +ACE_Filecache::ACE_Filecache (void) + : size_ (ACE_DEFAULT_VIRTUAL_FILESYSTEM_TABLE_SIZE), + hash_ (this->size_) +{ +} + +ACE_Filecache::~ACE_Filecache (void) +{ +} + +ACE_Filecache_Object * +ACE_Filecache::insert_i (const ACE_TCHAR *filename, + ACE_SYNCH_RW_MUTEX &filelock, + int mapit) +{ + ACE_Filecache_Object *handle = 0; + + if (this->hash_.find (filename, handle) == -1) + { + ACE_NEW_RETURN (handle, + ACE_Filecache_Object (filename, filelock, 0, mapit), + 0); + + // ACE_DEBUG ((LM_DEBUG, ACE_LIB_TEXT (" (%t) CVF: creating %s\n"), filename)); + + if (this->hash_.bind (filename, handle) == -1) + { + delete handle; + handle = 0; + } + } + else + handle = 0; + + return handle; +} + +ACE_Filecache_Object * +ACE_Filecache::remove_i (const ACE_TCHAR *filename) +{ + ACE_Filecache_Object *handle = 0; + + // Disassociate file from the cache. + if (this->hash_.unbind (filename, handle) == 0) + { + handle->stale_ = 1; + + // Try a lock. If it succeds, we can delete it now. + // Otherwise, it will clean itself up later. + if (handle->lock_.tryacquire_write () == 0) + { + delete handle; + handle = 0; + } + } + else + handle = 0; + + return handle; +} + +ACE_Filecache_Object * +ACE_Filecache::update_i (const ACE_TCHAR *filename, + ACE_SYNCH_RW_MUTEX &filelock, + int mapit) +{ + ACE_Filecache_Object *handle = 0; + + handle = this->remove_i (filename); + handle = this->insert_i (filename, filelock, mapit); + + return handle; +} + +int +ACE_Filecache::find (const ACE_TCHAR *filename) +{ + return this->hash_.find (filename); +} + + +ACE_Filecache_Object * +ACE_Filecache::remove (const ACE_TCHAR *filename) +{ + ACE_Filecache_Object *handle = 0; + + u_long loc = ACE::hash_pjw (filename) % this->size_; + ACE_SYNCH_RW_MUTEX &hashlock = this->hash_lock_[loc]; + // ACE_SYNCH_RW_MUTEX &filelock = this->file_lock_[loc]; + + if (this->hash_.find (filename, handle) != -1) + { + ACE_WRITE_GUARD_RETURN (ACE_SYNCH_RW_MUTEX, + ace_mon, + hashlock, + 0); + + return this->remove_i (filename); + } + + return 0; +} + + +ACE_Filecache_Object * +ACE_Filecache::fetch (const ACE_TCHAR *filename, int mapit) +{ + ACE_Filecache_Object *handle = 0; + + u_long loc = ACE::hash_pjw (filename) % this->size_; + ACE_SYNCH_RW_MUTEX &hashlock = this->hash_lock_[loc]; + ACE_SYNCH_RW_MUTEX &filelock = this->file_lock_[loc]; + + filelock.acquire_read (); + + if (this->hash_.find (filename, handle) == -1) + { + ACE_WRITE_GUARD_RETURN (ACE_SYNCH_RW_MUTEX, + ace_mon, + hashlock, + 0); + + // Second check in the method call + handle = this->insert_i (filename, filelock, mapit); + + if (handle == 0) + filelock.release (); + } + else + { + if (handle->update ()) + { + { + // Double check locking pattern + ACE_WRITE_GUARD_RETURN (ACE_SYNCH_RW_MUTEX, + ace_mon, + hashlock, + 0); + + // Second check in the method call + handle = this->update_i (filename, filelock, mapit); + + if (handle == 0) + filelock.release (); + } + } + // ACE_DEBUG ((LM_DEBUG, ACE_LIB_TEXT (" (%t) CVF: found %s\n"), filename)); + } + + return handle; +} + +ACE_Filecache_Object * +ACE_Filecache::create (const ACE_TCHAR *filename, int size) +{ + ACE_Filecache_Object *handle = 0; + + u_long loc = ACE::hash_pjw (filename) % this->size_; + ACE_SYNCH_RW_MUTEX &filelock = this->file_lock_[loc]; + + ACE_NEW_RETURN (handle, + ACE_Filecache_Object (filename, size, filelock), + 0); + handle->acquire (); + + return handle; +} + +ACE_Filecache_Object * +ACE_Filecache::finish (ACE_Filecache_Object *&file) +{ + if (file == 0) + return file; + + u_long loc = ACE::hash_pjw (file->filename_) % this->size_; + ACE_SYNCH_RW_MUTEX &hashlock = this->hash_lock_[loc]; + + if (file != 0) + switch (file->action_) + { + case ACE_Filecache_Object::ACE_WRITING: + { + ACE_WRITE_GUARD_RETURN (ACE_SYNCH_RW_MUTEX, + ace_mon, + hashlock, + 0); + + file->release (); + + this->remove_i (file->filename_); +#if 0 + int result = this->hash_.bind (file->filename (), file); + + if (result == 0) + file->acquire (); +#else + // Last one using a stale file is resposible for deleting it. + if (file->stale_) + { + // Try a lock. If it succeds, we can delete it now. + // Otherwise, it will clean itself up later. + if (file->lock_.tryacquire_write () == 0) + { + delete file; + file = 0; + } + } +#endif + } + + break; + default: + file->release (); + + // Last one using a stale file is resposible for deleting it. + if (file->stale_) + { + // Try a lock. If it succeds, we can delete it now. + // Otherwise, it will clean itself up later. + if (file->lock_.tryacquire_write () == 0) + { + delete file; + file = 0; + } + } + + break; + } + + return file; +} + +void +ACE_Filecache_Object::init (void) +{ + this->filename_[0] = '\0'; + this->handle_ = ACE_INVALID_HANDLE; + this->error_ = ACE_SUCCESS; + this->tempname_ = 0; + this->size_ = 0; + + ACE_OS::memset (&(this->stat_), 0, sizeof (this->stat_)); +} + +ACE_Filecache_Object::ACE_Filecache_Object (void) + : tempname_ (0), + mmap_ (), + handle_ (0), + // stat_ (), + size_ (0), + action_ (0), + error_ (0), + stale_ (0), + // sa_ (), + junklock_ (), + lock_ (junklock_) +{ + this->init (); +} + +ACE_Filecache_Object::ACE_Filecache_Object (const ACE_TCHAR *filename, + ACE_SYNCH_RW_MUTEX &lock, + LPSECURITY_ATTRIBUTES sa, + int mapit) + : tempname_ (0), + mmap_ (), + handle_ (0), + // stat_ (), + size_ (0), + action_ (0), + error_ (0), + stale_ (0), + sa_ (sa), + junklock_ (), + lock_ (lock) +{ + this->init (); + + // ASSERT strlen(filename) < sizeof (this->filename_) + ACE_OS::strcpy (this->filename_, filename); + this->action_ = ACE_Filecache_Object::ACE_READING; + // place ourselves into the READING state + + // Can we access the file? + if (ACE_OS::access (this->filename_, R_OK) == -1) + { + this->error_i (ACE_Filecache_Object::ACE_ACCESS_FAILED); + return; + } + + // Can we stat the file? + if (ACE_OS::stat (this->filename_, &this->stat_) == -1) + { + this->error_i (ACE_Filecache_Object::ACE_STAT_FAILED); + return; + } + + this->size_ = this->stat_.st_size; + this->tempname_ = this->filename_; + + // Can we open the file? + this->handle_ = ACE_OS::open (this->tempname_, + READ_FLAGS, R_MASK, this->sa_); + if (this->handle_ == ACE_INVALID_HANDLE) + { + this->error_i (ACE_Filecache_Object::ACE_OPEN_FAILED, + ACE_LIB_TEXT ("ACE_Filecache_Object::ctor: open")); + return; + } + + if (mapit) + { + // Can we map the file? + if (this->mmap_.map (this->handle_, -1, + PROT_READ, ACE_MAP_PRIVATE, 0, 0, this->sa_) != 0) + { + this->error_i (ACE_Filecache_Object::ACE_MEMMAP_FAILED, + ACE_LIB_TEXT ("ACE_Filecache_Object::ctor: map")); + ACE_OS::close (this->handle_); + this->handle_ = ACE_INVALID_HANDLE; + return; + } + } + + // Ok, finished! + this->action_ = ACE_Filecache_Object::ACE_READING; +} + +ACE_Filecache_Object::ACE_Filecache_Object (const ACE_TCHAR *filename, + off_t size, + ACE_SYNCH_RW_MUTEX &lock, + LPSECURITY_ATTRIBUTES sa) + : stale_ (0), + sa_ (sa), + lock_ (lock) +{ + this->init (); + + this->size_ = size; + ACE_OS::strcpy (this->filename_, filename); + this->action_ = ACE_Filecache_Object::ACE_WRITING; + + // Can we access the file? + if (ACE_OS::access (this->filename_, R_OK|W_OK) == -1 + // Does it exist? + && ACE_OS::access (this->filename_, F_OK) != -1) + { + // File exists, but we cannot access it. + this->error_i (ACE_Filecache_Object::ACE_ACCESS_FAILED); + return; + } + + this->tempname_ = this->filename_; + + // Can we open the file? + this->handle_ = ACE_OS::open (this->tempname_, WRITE_FLAGS, W_MASK, this->sa_); + if (this->handle_ == ACE_INVALID_HANDLE) + { + this->error_i (ACE_Filecache_Object::ACE_OPEN_FAILED, + ACE_LIB_TEXT ("ACE_Filecache_Object::acquire: open")); + return; + } + + // Can we write? + if (ACE_OS::pwrite (this->handle_, "", 1, this->size_ - 1) != 1) + { + this->error_i (ACE_Filecache_Object::ACE_WRITE_FAILED, + ACE_LIB_TEXT ("ACE_Filecache_Object::acquire: write")); + ACE_OS::close (this->handle_); + return; + } + + // Can we map? + if (this->mmap_.map (this->handle_, this->size_, PROT_RDWR, MAP_SHARED, + 0, 0, this->sa_) != 0) + { + this->error_i (ACE_Filecache_Object::ACE_MEMMAP_FAILED, + ACE_LIB_TEXT ("ACE_Filecache_Object::acquire: map")); + ACE_OS::close (this->handle_); + } + + // Ok, done! +} + +ACE_Filecache_Object::~ACE_Filecache_Object (void) +{ + if (this->error_ == ACE_SUCCESS) + { + this->mmap_.unmap (); + ACE_OS::close (this->handle_); + this->handle_ = ACE_INVALID_HANDLE; + } +} + +int +ACE_Filecache_Object::acquire (void) +{ + return this->lock_.tryacquire_read (); +} + +int +ACE_Filecache_Object::release (void) +{ + if (this->action_ == ACE_WRITING) + { + // We are safe since only one thread has a writable Filecache_Object + +#if 0 + ACE_HANDLE original = ACE_OS::open (this->filename_, WRITE_FLAGS, W_MASK, + this->sa_); + if (original == ACE_INVALID_HANDLE) + this->error_ = ACE_Filecache_Object::ACE_OPEN_FAILED; + else if (ACE_OS::write (original, this->mmap_.addr (), + this->size_) == -1) + { + this->error_ = ACE_Filecache_Object::ACE_WRITE_FAILED; + ACE_OS::close (original); + ACE_OS::unlink (this->filename_); + } + else if (ACE_OS::stat (this->filename_, &this->stat_) == -1) + this->error_ = ACE_Filecache_Object::ACE_STAT_FAILED; +#endif + + this->mmap_.unmap (); + ACE_OS::close (this->handle_); + this->handle_ = ACE_INVALID_HANDLE; + +#if 0 + // Leave the file in an acquirable state. + this->handle_ = ACE_OS::open (this->tempname_, READ_FLAGS, R_MASK); + if (this->handle_ == ACE_INVALID_HANDLE) + { + this->error_i (ACE_Filecache_Object::ACE_OPEN_FAILED, + "ACE_Filecache_Object::acquire: open"); + } + else if (this->mmap_.map (this->handle_, -1, + PROT_READ, + ACE_MAP_PRIVATE, + 0, + 0, + this->sa_) != 0) + { + this->error_i (ACE_Filecache_Object::ACE_MEMMAP_FAILED, + "ACE_Filecache_Object::acquire: map"); + ACE_OS::close (this->handle_); + this->handle_ = ACE_INVALID_HANDLE; + } + + this->action_ = ACE_Filecache_Object::ACE_READING; +#endif + } + + return this->lock_.release (); +} + +int +ACE_Filecache_Object::error (void) const +{ + // The existence of the object means a read lock is being held. + return this->error_; +} + +int +ACE_Filecache_Object::error_i (int error_value, const ACE_TCHAR *s) +{ + s = s; + ACE_ERROR ((LM_ERROR, ACE_LIB_TEXT ("%p.\n"), s)); + this->error_ = error_value; + return error_value; +} + +const ACE_TCHAR * +ACE_Filecache_Object::filename (void) const +{ + // The existence of the object means a read lock is being held. + return this->filename_; +} + +ACE_LOFF_T +ACE_Filecache_Object::size (void) const +{ + // The existence of the object means a read lock is being held. + return this->size_; +} + +ACE_HANDLE +ACE_Filecache_Object::handle (void) const +{ + // The existence of the object means a read lock is being held. + return this->handle_; +} + +void * +ACE_Filecache_Object::address (void) const +{ + // The existence of the object means a read lock is being held. + return this->mmap_.addr (); +} + +int +ACE_Filecache_Object::update (void) const +{ + // The existence of the object means a read lock is being held. + int result; + ACE_stat statbuf; + + if (ACE_OS::stat (this->filename_, &statbuf) == -1) + result = 1; + else + // non-portable code may follow +#if defined (ACE_HAS_WINCE) + // Yup, non-portable... there's probably a way to safely implement + // difftime() on WinCE, but for now, this will have to do. It flags + // every file as having changed since cached. + result = 1; +#else + result = ACE_OS::difftime (this->stat_.st_mtime, statbuf.st_mtime) < 0; +#endif /* ACE_HAS_WINCE */ + + return result; +} + +ACE_END_VERSIONED_NAMESPACE_DECL |