new branch to integrate BlockDevice, BlockCache

git-svn-id: https://profuse.googlecode.com/svn/branches/profuse_interim@334 aa027e90-d47c-11dd-86d7-074df07e0730
2026-02-15 05:35:18 +00:00 · 2011-02-19 18:07:28 +00:00
parent 5427db9990
commit c82cd3f8fa
4 changed files with 426 additions and 0 deletions
--- a/File/MappedFile.cpp
+++ b/File/MappedFile.cpp
@@ -0,0 +1,187 @@
+#include <algorithm>
+#include <cerrno>
+
+#include <sys/stat.h>
+
+#include <File/MappedFile.h>
+#include <ProFUSE/Exception.h>
+
+
+using ProFUSE::POSIXException;
+
+MappedFile::MappedFile()
+{
+    _length = -1;
+    _address = MAP_FAILED;
+    _readOnly = true;
+}
+
+MappedFile::MappedFile(MappedFile &mf)
+{
+    _address = mf._address;
+    _length = mf._length;
+    _readOnly = mf._readOnly;
+    
+    mf._address = MAP_FAILED;
+    mf._length = -1;
+    mf._readOnly = true;
+}
+
+MappedFile::MappedFile(const File &f, File::FileFlags flags, size_t size)
+{
+    _length = -1;
+    _address = MAP_FAILED;
+    _readOnly = true;
+    
+    init(f, flags == File::ReadOnly, size);
+}
+
+
+MappedFile::MappedFile(const char *name, File::FileFlags flags)
+{
+    File f(name, flags);
+    
+    _length = -1;
+    _address = MAP_FAILED;
+    _readOnly = true;
+    
+    init(f, flags == File::ReadOnly, 0);
+    
+}
+
+
+MappedFile::MappedFile(const char *name, File::FileFlags flags, const std::nothrow_t &nothrow)
+{
+    File f(name, flags, nothrow);
+    
+    _length = -1;
+    _address = MAP_FAILED;
+    _readOnly = true;
+    
+    if (f.isValid()) 
+        init(f, flags == File::ReadOnly, 0);
+}
+
+
+MappedFile::~MappedFile()
+{
+    close();
+}
+
+
+
+void MappedFile::init(const File &f, bool readOnly, size_t size)
+{
+#undef __METHOD__
+#define __METHOD__ "MappedFile::init"
+    
+    struct stat st;
+    int prot = readOnly ? PROT_READ : PROT_READ | PROT_WRITE;
+    int flags =  MAP_FILE | MAP_SHARED;
+    
+    // close enough
+    if (f.fd() < 0)
+        throw POSIXException( __METHOD__, EBADF);
+    
+    
+    if (!size)
+    {
+        if (::fstat(f.fd(), &st) != 0)
+            throw POSIXException(__METHOD__ ": fstat", errno);
+        
+        if (!S_ISREG(st.st_mode))
+            throw POSIXException(__METHOD__, ENODEV);
+        
+        size = st.st_size;
+    }
+    
+    _length = size;
+    _address = ::mmap(0, _length, prot, flags, f.fd(), 0); 
+    
+    if (_address == MAP_FAILED)
+        throw POSIXException(__METHOD__ ": mmap", errno);
+    
+    _readOnly = readOnly;
+}
+
+
+
+void MappedFile::close()
+{
+    #undef __METHOD__
+    #define __METHOD__ "MappedFile::close"
+    
+    if (_address != MAP_FAILED)
+    {
+        /*
+        void *address = _address;
+        size_t length = _length;
+        */
+        
+        ::munmap(_address, _length);
+        
+        _address = MAP_FAILED;
+        _length = -1;
+        _readOnly = true;
+        
+        // destructor shouldn't throw.
+        /*
+        if (::munmap(address, length) != 0)
+            throw POSIXException(__METHOD__ ": munmap", errno);
+         */
+    }
+}
+
+void MappedFile::sync()
+{
+    #undef __METHOD__
+    #define __METHOD__ "MappedFile::sync"
+    
+    if (_address != MAP_FAILED)
+    {
+        if (::msync(_address, _length, MS_SYNC) != 0)
+            throw POSIXException(__METHOD__ ": msync", errno);
+    }
+}
+
+void MappedFile::adopt(MappedFile &mf)
+{
+    close();
+    _address = mf._address;
+    _length = mf._length;
+    _readOnly = mf._readOnly;
+    
+    mf._address = MAP_FAILED;
+    mf._length = -1;
+    mf._readOnly = true;
+}
+
+void MappedFile::swap(MappedFile &mf)
+{
+    std::swap(_address, mf._address);
+    std::swap(_length, mf._length);
+    std::swap(_readOnly, mf._readOnly);
+}
+
+
+MappedFile *MappedFile::Create(const char *name, size_t size)
+{
+#undef __METHOD__
+#define __METHOD__ "MappedFile::Create"
+    
+    File fd(::open(name, O_CREAT | O_TRUNC | O_RDWR, 0644));
+
+    if (!fd.isValid())
+    {
+        throw POSIXException(__METHOD__ ": Unable to create file.", errno);        
+    }
+
+    // TODO -- is ftruncate portable?
+    if (::ftruncate(fd.fd(), size) < 0)
+    {
+        // TODO -- unlink?
+        throw POSIXException(__METHOD__ ": Unable to truncate file.", errno);    
+    }
+    
+    return new MappedFile(fd, File::ReadWrite, size);
+}