X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=snapshot.cc;h=fb1f911557e09345ed7b8299e19d6edce97eb399;hb=ea4611c1fc3b580020afbc04d531e4bc10fcca9c;hp=fe5110a03fe5a7b0e45e3b62471788eb396a9aed;hpb=2ada1a461101f16a0be8ba75200c8ae4f9ff9d84;p=model-checker.git

diff --git a/snapshot.cc b/snapshot.cc
index fe5110a..fb1f911 100644
--- a/snapshot.cc
+++ b/snapshot.cc
@@ -46,8 +46,19 @@ struct MemoryRegion {
 	int sizeInPages; // size of memory region in pages
 };
 
+/** ReturnPageAlignedAddress returns a page aligned address for the
+ * address being added as a side effect the numBytes are also changed.
+ */
+static void * ReturnPageAlignedAddress(void *addr)
+{
+	return (void *)(((uintptr_t)addr) & ~(PAGESIZE - 1));
+}
+
 /* Primary struct for snapshotting system */
 struct mprot_snapshotter {
+	mprot_snapshotter(unsigned int numbackingpages, unsigned int numsnapshots, unsigned int nummemoryregions);
+	~mprot_snapshotter();
+
 	struct MemoryRegion *regionsToSnapShot; //This pointer references an array of memory regions to snapshot
 	snapshot_page_t *backingStore; //This pointer references an array of snapshotpage's that form the backing store
 	void *backingStoreBasePtr; //This pointer references an array of snapshotpage's that form the backing store
@@ -61,42 +72,40 @@ struct mprot_snapshotter {
 	unsigned int maxRegions; //Stores the max number of memory regions we support
 	unsigned int maxBackingPages; //Stores the total number of backing pages
 	unsigned int maxSnapShots; //Stores the total number of snapshots we allow
+
+	MEMALLOC
 };
 
 static struct mprot_snapshotter *mprot_snap = NULL;
 
-/** ReturnPageAlignedAddress returns a page aligned address for the
- * address being added as a side effect the numBytes are also changed.
- */
-static void * ReturnPageAlignedAddress(void *addr)
+mprot_snapshotter::mprot_snapshotter(unsigned int backing_pages, unsigned int snapshots, unsigned int regions) :
+	lastSnapShot(0),
+	lastBackingPage(0),
+	lastRegion(0),
+	maxRegions(regions),
+	maxBackingPages(backing_pages),
+	maxSnapShots(snapshots)
 {
-	return (void *)(((uintptr_t)addr) & ~(PAGESIZE - 1));
+	regionsToSnapShot = (struct MemoryRegion *)model_malloc(sizeof(struct MemoryRegion) * regions);
+	backingStoreBasePtr = (void *)model_malloc(sizeof(snapshot_page_t) * (backing_pages + 1));
+	//Page align the backingstorepages
+	backingStore = (snapshot_page_t *)PageAlignAddressUpward(backingStoreBasePtr);
+	backingRecords = (struct BackingPageRecord *)model_malloc(sizeof(struct BackingPageRecord) * backing_pages);
+	snapShots = (struct SnapShotRecord *)model_malloc(sizeof(struct SnapShotRecord) * snapshots);
 }
 
-/** The initSnapShotRecord method initialized the snapshotting data
- *  structures for the mprotect based snapshot.
- */
-static void initSnapShotRecord(unsigned int numbackingpages, unsigned int numsnapshots, unsigned int nummemoryregions)
+mprot_snapshotter::~mprot_snapshotter()
 {
-	mprot_snap = (struct mprot_snapshotter *)model_malloc(sizeof(struct mprot_snapshotter));
-	mprot_snap->regionsToSnapShot = (struct MemoryRegion *)model_malloc(sizeof(struct MemoryRegion) * nummemoryregions);
-	mprot_snap->backingStoreBasePtr = (void *)model_malloc(sizeof(snapshot_page_t) * (numbackingpages + 1));
-	//Page align the backingstorepages
-	mprot_snap->backingStore = (snapshot_page_t *)PageAlignAddressUpward(mprot_snap->backingStoreBasePtr);
-	mprot_snap->backingRecords = (struct BackingPageRecord *)model_malloc(sizeof(struct BackingPageRecord) * numbackingpages);
-	mprot_snap->snapShots = (struct SnapShotRecord *)model_malloc(sizeof(struct SnapShotRecord) * numsnapshots);
-	mprot_snap->lastSnapShot = 0;
-	mprot_snap->lastBackingPage = 0;
-	mprot_snap->lastRegion = 0;
-	mprot_snap->maxRegions = nummemoryregions;
-	mprot_snap->maxBackingPages = numbackingpages;
-	mprot_snap->maxSnapShots = numsnapshots;
+	model_free(regionsToSnapShot);
+	model_free(backingStoreBasePtr);
+	model_free(backingRecords);
+	model_free(snapShots);
 }
 
-/** HandlePF is the page fault handler for mprotect based snapshotting
+/** mprot_handle_pf is the page fault handler for mprotect based snapshotting
  * algorithm.
  */
-static void HandlePF(int sig, siginfo_t *si, void *unused)
+static void mprot_handle_pf(int sig, siginfo_t *si, void *unused)
 {
 	if (si->si_code == SEGV_MAPERR) {
 		model_print("Real Fault at %p\n", si->si_addr);
@@ -138,7 +147,7 @@ static void mprot_snapshot_init(unsigned int numbackingpages,
 	struct sigaction sa;
 	sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART | SA_ONSTACK;
 	sigemptyset(&sa.sa_mask);
-	sa.sa_sigaction = HandlePF;
+	sa.sa_sigaction = mprot_handle_pf;
 #ifdef MAC
 	if (sigaction(SIGBUS, &sa, NULL) == -1) {
 		model_print("SIGACTION CANNOT BE INSTALLED\n");
@@ -150,27 +159,27 @@ static void mprot_snapshot_init(unsigned int numbackingpages,
 		exit(EXIT_FAILURE);
 	}
 
-	initSnapShotRecord(numbackingpages, numsnapshots, nummemoryregions);
+	mprot_snap = new mprot_snapshotter(numbackingpages, numsnapshots, nummemoryregions);
 
-	// EVIL HACK: We need to make sure that calls into the HandlePF method don't cause dynamic links
+	// EVIL HACK: We need to make sure that calls into the mprot_handle_pf method don't cause dynamic links
 	// The problem is that we end up protecting state in the dynamic linker...
 	// Solution is to call our signal handler before we start protecting stuff...
 
 	siginfo_t si;
 	memset(&si, 0, sizeof(si));
 	si.si_addr = ss.ss_sp;
-	HandlePF(SIGSEGV, &si, NULL);
+	mprot_handle_pf(SIGSEGV, &si, NULL);
 	mprot_snap->lastBackingPage--; //remove the fake page we copied
 
 	void *basemySpace = model_malloc((numheappages + 1) * PAGESIZE);
 	void *pagealignedbase = PageAlignAddressUpward(basemySpace);
 	user_snapshot_space = create_mspace_with_base(pagealignedbase, numheappages * PAGESIZE, 1);
-	addMemoryRegionToSnapShot(pagealignedbase, numheappages);
+	snapshot_add_memory_region(pagealignedbase, numheappages);
 
 	void *base_model_snapshot_space = model_malloc((numheappages + 1) * PAGESIZE);
 	pagealignedbase = PageAlignAddressUpward(base_model_snapshot_space);
 	model_snapshot_space = create_mspace_with_base(pagealignedbase, numheappages * PAGESIZE, 1);
-	addMemoryRegionToSnapShot(pagealignedbase, numheappages);
+	snapshot_add_memory_region(pagealignedbase, numheappages);
 
 	entryPoint();
 }
@@ -389,10 +398,11 @@ static void fork_roll_back(snapshot_id theID)
 
 #endif /* !USE_MPROTECT_SNAPSHOT */
 
-/** The initSnapshotLibrary function initializes the snapshot library.
- *  @param entryPoint the function that should run the program.
+/**
+ * @brief Initializes the snapshot system
+ * @param entryPoint the function that should run the program.
  */
-void initSnapshotLibrary(unsigned int numbackingpages,
+void snapshot_system_init(unsigned int numbackingpages,
 		unsigned int numsnapshots, unsigned int nummemoryregions,
 		unsigned int numheappages, VoidFuncPtr entryPoint)
 {
@@ -403,8 +413,8 @@ void initSnapshotLibrary(unsigned int numbackingpages,
 #endif
 }
 
-/** The addMemoryRegionToSnapShot function assumes that addr is page aligned. */
-void addMemoryRegionToSnapShot(void *addr, unsigned int numPages)
+/** Assumes that addr is page aligned. */
+void snapshot_add_memory_region(void *addr, unsigned int numPages)
 {
 #if USE_MPROTECT_SNAPSHOT
 	mprot_add_to_snapshot(addr, numPages);
@@ -413,10 +423,10 @@ void addMemoryRegionToSnapShot(void *addr, unsigned int numPages)
 #endif
 }
 
-/** The takeSnapshot function takes a snapshot.
+/** Takes a snapshot of memory.
  * @return The snapshot identifier.
  */
-snapshot_id takeSnapshot()
+snapshot_id take_snapshot()
 {
 #if USE_MPROTECT_SNAPSHOT
 	return mprot_take_snapshot();
@@ -425,10 +435,10 @@ snapshot_id takeSnapshot()
 #endif
 }
 
-/** The rollBack function rollback to the given snapshot identifier.
+/** Rolls the memory state back to the given snapshot identifier.
  *  @param theID is the snapshot identifier to rollback to.
  */
-void rollBack(snapshot_id theID)
+void snapshot_roll_back(snapshot_id theID)
 {
 #if USE_MPROTECT_SNAPSHOT
 	mprot_roll_back(theID);