posix/map: start extracting pure mmap class

Makefile.am

@@ -292,6 +292,8 @@ POSIX_FILES = 			\
     posix/dir.ipp		\
     posix/fd.cpp		\
     posix/fd.hpp		\
+    posix/map.cpp		\
+    posix/map.hpp		\
     time_posix.cpp
 
 

posix/map.cpp

@@ -0,0 +1,132 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Copyright 2016 Danny Robson <danny@nerdcruft.net>
+ */
+
+#include "map.hpp"
+
+#include "../except.hpp"
+
+using util::posix::map;
+
+
+///////////////////////////////////////////////////////////////////////////////
+map::map (size_t size, int prot, int flags):
+    m_addr (mmap (nullptr, size, prot, flags, -1, 0)),
+    m_size (size)
+{
+    if (MAP_FAILED == m_addr)
+        ::util::errno_error::throw_code ();
+}
+
+
+//-----------------------------------------------------------------------------
+map::map (size_t size, int prot, int flags, const fd &src, off_t offset):
+    m_addr (mmap (nullptr, size, prot, flags, src, offset)),
+    m_size (size)
+{
+    if (MAP_FAILED == m_addr)
+        ::util::errno_error::throw_code ();
+}
+
+
+//-----------------------------------------------------------------------------
+map::map (map &&rhs):
+    m_addr (MAP_FAILED),
+    m_size (rhs.m_size)
+{
+    std::swap (m_addr, rhs.m_addr);
+}
+
+
+//-----------------------------------------------------------------------------
+map::~map ()
+{
+    if (MAP_FAILED == m_addr)
+        return;
+
+    if (munmap (m_addr, m_size))
+        ::util::errno_error::throw_code ();
+}
+
+
+//-----------------------------------------------------------------------------
+map&
+map::operator= (map &&rhs)
+{
+    std::swap (m_addr, rhs.m_addr);
+    std::swap (m_size, rhs.m_size);
+
+    return *this;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+uint8_t*
+map::begin (void)
+{
+    return static_cast<uint8_t*> (m_addr);
+}
+
+
+//-----------------------------------------------------------------------------
+uint8_t*
+map::end (void)
+{
+    return static_cast<uint8_t*> (m_addr) + m_size;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+void*
+map::data (void)
+{
+    return m_addr;
+}
+
+
+//-----------------------------------------------------------------------------
+const void*
+map::data (void) const
+{
+    return m_addr;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+size_t
+map::size (void) const
+{
+    return m_size;
+}
+
+
+//-----------------------------------------------------------------------------
+void
+map::resize (size_t newsize, resize_t op)
+{
+    int flags = 0;
+    switch (op) {
+    case resize_t::MOVE:
+        flags = flags | MREMAP_MAYMOVE;
+        break;
+
+    case resize_t::NOMOVE:
+        break;
+    }
+
+    auto res = mremap (m_addr, m_size, newsize, flags);
+    if (res == MAP_FAILED)
+        ::util::errno_error::throw_code ();
+}

posix/map.hpp

@@ -0,0 +1,62 @@
+/*
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Copyright 2016 Danny Robson <danny@nerdcruft.net>
+ */
+
+#ifndef __CRUFT_UTIL_POSIX_HPP
+#define __CRUFT_UTIL_POSIX_HPP
+
+#include "./fd.hpp"
+
+#include <sys/mman.h>
+#include <cstdint>
+
+
+namespace util::posix {
+    class map {
+    public:
+        map (const map&) = delete;
+        map (map&&);
+
+        map (size_t size, int prot, int flags);
+        map (size_t size, int prot, int flags, const fd&, off_t offset = 0);
+        ~map ();
+
+        map& operator= (const map&) = delete;
+        map& operator= (map&&);
+
+        uint8_t* begin (void);
+        uint8_t* end   (void);
+        const uint8_t* begin (void) const;
+        const uint8_t* end   (void) const;
+        const uint8_t* cbegin (void) const;
+        const uint8_t* cend   (void) const;
+
+        void* data (void);
+        const void* data (void) const;
+
+        void sync (void *addr, size_t len, int flags);
+
+        size_t size (void) const;
+
+        enum class resize_t { MOVE, NOMOVE };
+        void resize (size_t newsize, resize_t = resize_t::NOMOVE);
+
+    private:
+        void    *m_addr;
+        size_t   m_size;
+    };
+}
+
+#endif