Adding libutil as source instead of patch

libutil/ExtentManager.cpp

@@ -0,0 +1,305 @@
+/*
+ * Copyright (c) 2008-2009,2011 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+//
+//	ExtentManager.cpp
+//
+
+#include "ExtentManager.h"
+
+void
+ExtentManager::Init(uint32_t theBlockSize, uint32_t theNativeBlockSize, off_t theTotalBytes)
+{
+	blockSize = theBlockSize;
+	nativeBlockSize = theNativeBlockSize;
+	totalBytes = theTotalBytes;
+	totalBlocks = howmany(totalBytes, blockSize);
+
+	// add sentry empty extents at both sides so empty partition doesn't need to be handled specially
+	AddBlockRangeExtent(0, 0);
+	AddBlockRangeExtent(totalBlocks, 0);
+}
+
+void
+ExtentManager::MergeExtent(const ExtentInfo &a, const ExtentInfo &b, ExtentInfo *c)
+{
+	// merge ext into *curIt
+	c->blockAddr = min(a.blockAddr, b.blockAddr);
+	c->numBlocks = max(a.blockAddr + a.numBlocks, b.blockAddr + b.numBlocks) - c->blockAddr;
+}
+
+void
+ExtentManager::AddBlockRangeExtent(off_t blockAddr, off_t numBlocks)
+{
+	struct ExtentInfo ext, newExt;
+	ListExtIt curIt, newIt;
+	bool merged = false;
+
+	// make the range a valid range
+	if ((blockAddr > totalBlocks) || (blockAddr + numBlocks < 0)) { // totally out of range, do nothing
+		return;
+	}
+	if (blockAddr < 0) {
+		numBlocks = blockAddr + numBlocks;
+		blockAddr = 0;
+	}
+	if (blockAddr + numBlocks > totalBlocks) {
+		numBlocks = totalBlocks - blockAddr;
+	}
+
+	ext.blockAddr = blockAddr;
+	ext.numBlocks = numBlocks;
+
+	for (curIt = extentList.begin(); curIt != extentList.end(); curIt++) {
+		if (BeforeExtent(ext, *curIt))
+			break;
+		if (!BeforeExtent(*curIt, ext)) { // overlapped extents
+			MergeExtent(ext, *curIt, &newExt);
+			*curIt = newExt;
+			merged = true;
+			break;
+		}
+	}
+
+	// insert ext before curIt
+	if (!merged) {
+		curIt = extentList.insert(curIt, ext); // throws bad_alloc when out of memory
+	}
+
+	// merge the extents
+	newIt = curIt;
+	curIt = extentList.begin();
+	while (curIt != extentList.end()) {
+		if (curIt == newIt || BeforeExtent(*curIt, *newIt)) { // curIt is before newIt
+			curIt++;
+			continue;
+		}
+		if (BeforeExtent(*newIt, *curIt)) { // curIt is after newIt now, we are done
+			break;
+		}
+		// merge the two extents
+		MergeExtent(*curIt, *newIt, &newExt);
+		*newIt = newExt;
+		curIt = extentList.erase(curIt);
+	}
+	// printf("After %s(%lld, %lld)\n", __func__, blockAddr, numBlocks);	 DebugPrint();
+} // ExtentManager::AddBlockRangeExtent
+
+void
+ExtentManager::RemoveBlockRangeExtent(off_t blockAddr, off_t numBlocks)
+{
+	struct ExtentInfo ext, newExt;
+	ListExtIt curIt;
+
+	ext.blockAddr = blockAddr;
+	ext.numBlocks = numBlocks;
+
+	curIt = extentList.begin();
+	while (curIt != extentList.end()) {
+		if (BeforeExtent(*curIt, ext)) {
+			curIt++;
+			continue;
+		}
+		if (BeforeExtent(ext, *curIt)) // we are done
+			break;
+
+		//
+		// If we get here, the input extent and *curIt have at least one block in common.
+		// That is, they overlap in some way.  Thus *curIt needs to change, be removed,
+		// or be split into two non-contiguous extents.
+		//
+
+		if (curIt->blockAddr >= ext.blockAddr &&
+			curIt->blockAddr + curIt->numBlocks <= ext.blockAddr + ext.numBlocks) {
+			//
+			// The input extent totally contains *curIt, so remove *curIt.
+			//
+			curIt = extentList.erase(curIt);
+		} else if (curIt->blockAddr < ext.blockAddr &&
+			curIt->blockAddr + curIt->numBlocks > ext.blockAddr + ext.numBlocks) {
+			//
+			// The input extent does not include the start of *curIt, nor the end of *curIt,
+			// so split *curIt into two extents.
+			//
+			newExt.blockAddr = ext.blockAddr + ext.numBlocks;
+			newExt.numBlocks = curIt->blockAddr + curIt->numBlocks - newExt.blockAddr;
+			curIt->numBlocks = ext.blockAddr - curIt->blockAddr;
+			curIt++;
+			extentList.insert(curIt, newExt); // throws bad_alloc when out of memory
+			curIt++;	
+		} else {
+			//
+			// The input extent contains either the start or the end of *curIt, but not both.
+			// The remove will leave either the end or the start of *curIt (respectively) and
+			// not change the number of extents in the list.
+			//
+			if (curIt->blockAddr >= ext.blockAddr) {
+				//
+				// Remove the start of *curIt by updating both its starting block and size.
+				//
+				assert(curIt->blockAddr + curIt->numBlocks > ext.blockAddr + ext.numBlocks);
+				newExt.blockAddr = ext.blockAddr + ext.numBlocks;
+				newExt.numBlocks = curIt->blockAddr + curIt->numBlocks - newExt.blockAddr;
+				*curIt = newExt;
+			} else {
+				//
+				// Remove the end of *curIt by updating its size.
+				//
+				curIt->numBlocks = ext.blockAddr - curIt->blockAddr;
+			}
+			curIt++;
+		}
+	}
+	//printf("After %s(%lld, %lld)\n", __func__, blockAddr, numBlocks);	 DebugPrint();
+}
+
+void
+ExtentManager::AddByteRangeExtent(off_t byteAddr, off_t numBytes)
+{
+	off_t blockAddr = byteAddr / blockSize;
+	off_t blockAddrOfLastByte = (byteAddr + numBytes - 1) / blockSize;
+	off_t numBlocks = blockAddrOfLastByte - blockAddr + 1;
+	AddBlockRangeExtent(blockAddr, numBlocks);
+}
+
+void
+ExtentManager::DebugPrint()
+{
+	ListExtIt it;
+
+	for (it = extentList.begin(); it != extentList.end(); it++) {
+		printf("[%lld, %lld] ", it->blockAddr, it->numBlocks);
+	}
+	printf("\n");
+}
+
+
+#if UNIT_TEST
+
+/*
+clang++ -arch i386 -arch x86_64 -DUNIT_TEST ExtentManager.cpp -o ExtentManager && ./ExtentManager
+*/
+
+#include <cstdio>
+#include <cstdlib>
+
+const char *DebugDescription(class ExtentManager *extMan)
+{
+	char *result = strdup("");
+	char *temp;
+
+	ListExtIt it;
+
+	for (it = extMan->extentList.begin(); it != extMan->extentList.end(); it++) {
+		temp = result;
+		asprintf(&result, "%s[%lld, %lld] ", temp, it->blockAddr, it->numBlocks);
+		free(temp);
+	}
+
+	return result;
+}
+
+int SimpleTestCase(off_t addAddr, off_t addBlocks, off_t removeAddr, off_t removeBlocks, const char *expectedResult)
+{
+	class ExtentManager extMan;
+	const char *actualResult;
+	int result = 0;
+
+	extMan.Init(512, 512, 512*999);
+	extMan.AddBlockRangeExtent(addAddr, addBlocks);
+	extMan.RemoveBlockRangeExtent(removeAddr, removeBlocks);
+	actualResult = DebugDescription(&extMan);
+	if (strcmp(actualResult, expectedResult))
+	{
+		fprintf(stderr,
+				"SimpleTestCase(%lld, %lld, %lld, %lld) failed.\n"
+				"    Expected result: %s\n"
+				"      Actual result: %s\n",
+				addAddr, addBlocks, removeAddr, removeBlocks,
+				expectedResult, actualResult);
+		result = 1;
+	}
+	free((void *)actualResult);
+
+	return result;
+}
+
+int main(void)
+{
+	int failed = 0;
+	class ExtentManager *extMan;
+
+	// Create an extent, and remove one contained inside,
+	// leaving the start and end of the original extent.
+	// Create: [xxxxxxxxxx]
+	// Remove:   [......]
+	failed |= SimpleTestCase(10, 10, 12, 6, "[0, 0] [10, 2] [18, 2] [999, 0] ");
+
+	// Create an extent, and remove the whole extent.
+	// Create: [xxxxxxxxxx]
+	// Remove: [..........]
+	failed |= SimpleTestCase(10, 10, 10, 10, "[0, 0] [999, 0] ");
+
+	// Create an extent, and remove the first part of the extent.
+	// Create: [xxxxxxxxxx]
+	// Remove: [......]
+	failed |= SimpleTestCase(10, 10, 10, 6, "[0, 0] [16, 4] [999, 0] ");
+
+	// Create an extent, and remove the last part of the extent.
+	// Create: [xxxxxxxxxx]
+	// Remove:     [......]
+	failed |= SimpleTestCase(10, 10, 14, 6, "[0, 0] [10, 4] [999, 0] ");
+
+	// Create an extent and remove before the start, through the middle.
+	// Create:     [xxxxxxxxxx]
+	// Remove: [..........]
+	failed |= SimpleTestCase(10, 10, 6, 10, "[0, 0] [16, 4] [999, 0] ");
+
+	// Create an extent and remove from middle to past the end.
+	// Create: [xxxxxxxxxx]
+	// Remove:     [..........]
+	failed |= SimpleTestCase(10, 10, 14, 10, "[0, 0] [10, 4] [999, 0] ");
+
+	// Create an extent and remove from before through past end.
+	// Create:   [xxxxxxxxxx]
+	// Remove: [..............]
+	failed |= SimpleTestCase(10, 10, 6, 18, "[0, 0] [999, 0] ");
+
+	// Create an extent and remove purely before the extent.
+	// Create:      [xxxxxxxxxx]
+	// Remove: [...]
+	failed |= SimpleTestCase(10, 10, 2, 5, "[0, 0] [10, 10] [999, 0] ");
+
+	// Create an extent and remove purely after the extent.
+	// Create: [xxxxxxxxxx]
+	// Remove:              [...]
+	failed |= SimpleTestCase(10, 10, 22, 5, "[0, 0] [10, 10] [999, 0] ");
+
+	if (failed)
+		printf("FAIL!\n");
+	else
+		printf("Success.\n");
+
+	return failed;
+}
+
+#endif /* UNIT_TEST */

libutil/ExtentManager.h

@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2008 Computer, Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+//
+//	ExtentManager.h
+//
+#ifndef EXTENTMANAGER_H
+#define EXTENTMANAGER_H
+
+#include <list>
+#include <vector>
+#include <algorithm>
+#include <sys/types.h>
+#include <sys/errno.h>
+#include <cstdio>
+#include <cassert>
+using namespace std;
+
+struct ExtentInfo {
+	off_t blockAddr;
+	off_t numBlocks;
+};
+
+inline bool BeforeExtent(const ExtentInfo &a, const ExtentInfo &b)
+{
+		return (a.blockAddr + a.numBlocks) < b.blockAddr;
+}
+
+typedef list<ExtentInfo>::iterator ListExtIt;
+
+class ExtentManager {
+public:
+	ExtentManager() : blockSize(0), totalBytes(0), totalBlocks(0) {};
+	~ExtentManager() {};
+
+	void Init(uint32_t theBlockSize, uint32_t theNativeBlockSize, off_t theTotalBytes);
+
+	void AddBlockRangeExtent(off_t blockAddr, off_t numBlocks);
+	void AddByteRangeExtent(off_t byteAddr, off_t numBytes);
+	void RemoveBlockRangeExtent(off_t blockAddr, off_t numBlocks);
+
+	void DebugPrint();
+
+protected:
+	void MergeExtent(const ExtentInfo &a, const ExtentInfo &b, ExtentInfo *c);
+
+public:
+	size_t blockSize;
+	size_t nativeBlockSize;
+	off_t totalBytes;
+	off_t totalBlocks;
+	list<ExtentInfo> extentList;
+};
+
+#endif // #ifndef EXTENTMANAGER_H