diff -r 000000000000 -r 31a43d94cc26 src/MemoryMap.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/MemoryMap.cpp	Sun Sep 20 15:14:12 2009 -0700
@@ -0,0 +1,103 @@
+/*
+ *  MemoryMap.cpp
+ *  Ottoman
+ *
+ *  Created by Jens Alfke on 9/17/09.
+ *  Copyright 2009 Jens Alfke. All rights reserved.
+ *  BSD-Licensed: See the file "LICENSE.txt" for details.
+ */
+
+#include "MemoryMap.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <sys/mman.h>
+
+namespace Mooseyard {
+
+    MemoryMap::~MemoryMap() {
+        for (int i=0; i<_nRegions; i++)
+            delete _regions[i];
+        free(_regions);
+    }
+
+    void MemoryMap::mapRegion (off_t pos, size_t length) {
+        size_t end = pos+length;
+        for (int i=0; i<_nRegions; i++) {
+            Region *region = _regions[i];
+            if (region->position() <= pos) {
+                if (end <= region->end())
+                    return;     // found an existing region covering this range
+                else if (region->setLength(end - region->position()))
+                    return;     // able to grow the existing region
+            }
+        }
+        
+        // No existing region, so add a new one:
+        Region *region = new Region(_file, pos,length);
+        _regions = (Region**) realloc(_regions, (_nRegions+1)*sizeof(*_regions));
+        _regions[_nRegions++] = region;
+    }
+
+    const void* MemoryMap::_at (off_t pos) const {
+        for (int i=0; i<_nRegions; i++) {
+            const void *ptr = _regions[i]->mappedPosition(pos);
+            if (ptr)
+                return ptr;
+        }
+        return NULL;
+    }
+    
+    const void* MemoryMap::mappedPosition (off_t pos) const {
+        const void *result = _at(pos);
+        if (!result)
+            throw File::Error("No memory mapped at this position");
+        return result;
+    }
+
+    
+    
+    
+    MemoryMap::Region::Region (File* file, off_t position, size_t length)
+    :_file(file),
+    _position(position),
+    _length (length),
+    _start( (const uint8_t*) ::mmap(NULL, length, PROT_READ, MAP_PRIVATE, file->_fd, position) )
+    {
+        printf("File#%i: Mapped (%6llu -- %6llu) --> %p\n", file->_fd, _position, end(), _start);
+        if (_start==NULL || _start == MAP_FAILED) {
+            _start = NULL;
+            throw File::Error(errno, strerror(errno));
+        }
+    }
+    
+    MemoryMap::Region::~Region() {
+        if (_start) {
+            printf("File#%i: Unmapped (%6llu -- %6llu) from %p\n", _file->_fd, _position, end(), _start);
+            ::munmap((void*)_start,_length);
+        }
+    }
+    
+    bool MemoryMap::Region::setLength (size_t length) {
+        if (length != _length) {
+            printf("File#%i: Resiging (%6llu -- %6llu) from %lu to %lu ...", 
+                   _file->_fd, _position, end(), _length,length);
+            if (::mmap((void*)_start, length, PROT_READ, MAP_PRIVATE | MAP_FIXED, _file->_fd, _position) == MAP_FAILED) {
+                printf("failed! errno=%i\n", errno);
+                return false;
+            }
+            printf("OK\n");
+            _length = length;
+        }
+        return true;
+    }
+    
+    const void* MemoryMap::Region::mappedPosition (off_t pos) {
+        if (pos >= _position && pos < end())
+            return _start + (pos-_position);
+        else
+            return NULL;
+    }
+    
+    
+}