1 files changed, 124 insertions, 0 deletions
diff --git a/botan/src/alloc/alloc_mmap/mmap_mem.cpp b/botan/src/alloc/alloc_mmap/mmap_mem.cpp
new file mode 100644
index 0000000..546da7a
--- /dev/null
+++ b/botan/src/alloc/alloc_mmap/mmap_mem.cpp
@@ -0,0 +1,124 @@
+/*
+* Memory Mapping Allocator
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/mmap_mem.h>
+#include <cstring>
+
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <fcntl.h>
+
+#ifndef MAP_FAILED
+   #define MAP_FAILED -1
+#endif
+
+namespace Botan {
+
+namespace {
+
+/*
+* MemoryMapping_Allocator Exception
+*/
+class MemoryMapping_Failed : public Exception
+   {
+   public:
+      MemoryMapping_Failed(const std::string& msg) :
+         Exception("MemoryMapping_Allocator: " + msg) {}
+   };
+
+}
+
+/*
+* Memory Map a File into Memory
+*/
+void* MemoryMapping_Allocator::alloc_block(u32bit n)
+   {
+   class TemporaryFile
+      {
+      public:
+         int get_fd() const { return fd; }
+         const std::string path() const { return filepath; }
+
+         TemporaryFile(const std::string& base)
+            {
+            const std::string path = base + "XXXXXX";
+
+            filepath = new char[path.length() + 1];
+            std::strcpy(filepath, path.c_str());
+
+            mode_t old_umask = ::umask(077);
+            fd = ::mkstemp(filepath);
+            ::umask(old_umask);
+            }
+
+         ~TemporaryFile()
+            {
+            delete[] filepath;
+            if(fd != -1 && ::close(fd) == -1)
+               throw MemoryMapping_Failed("Could not close file");
+            }
+      private:
+         int fd;
+         char* filepath;
+      };
+
+   TemporaryFile file("/tmp/botan_");
+
+   if(file.get_fd() == -1)
+      throw MemoryMapping_Failed("Could not create file");
+
+   if(::unlink(file.path().c_str()))
+      throw MemoryMapping_Failed("Could not unlink file '" + file.path() + "'");
+
+   if(::lseek(file.get_fd(), n-1, SEEK_SET) < 0)
+      throw MemoryMapping_Failed("Could not seek file");
+
+   if(::write(file.get_fd(), "\0", 1) != 1)
+      throw MemoryMapping_Failed("Could not write to file");
+
+#ifndef MAP_NOSYNC
+   #define MAP_NOSYNC 0
+#endif
+
+   void* ptr = ::mmap(0, n,
+                      PROT_READ | PROT_WRITE,
+                      MAP_SHARED | MAP_NOSYNC,
+                      file.get_fd(), 0);
+
+   if(ptr == static_cast<void*>(MAP_FAILED))
+      throw MemoryMapping_Failed("Could not map file");
+
+   return ptr;
+   }
+
+/*
+* Remove a Memory Mapping
+*/
+void MemoryMapping_Allocator::dealloc_block(void* ptr, u32bit n)
+   {
+   if(ptr == 0)
+      return;
+
+   const byte PATTERNS[] = { 0x00, 0xFF, 0xAA, 0x55, 0x73, 0x8C, 0x5F, 0xA0,
+                             0x6E, 0x91, 0x30, 0xCF, 0xD3, 0x2C, 0xAC, 0x00 };
+
+   for(u32bit j = 0; j != sizeof(PATTERNS); j++)
+      {
+      std::memset(ptr, PATTERNS[j], n);
+
+      if(::msync(ptr, n, MS_SYNC))
+         throw MemoryMapping_Failed("Sync operation failed");
+      }
+
+   if(::munmap(ptr, n))
+      throw MemoryMapping_Failed("Could not unmap file");
+   }
+
+}