#include <ucontext.h>
//extern declaration definition
-#define FAILURE(mesg) { printf("failed in the API: %s with errno relative message: %s\n", mesg, strerror( errno ) ); exit( -1 ); }
+#define FAILURE(mesg) { printf("failed in the API: %s with errno relative message: %s\n", mesg, strerror( errno ) ); exit(EXIT_FAILURE); }
#if USE_MPROTECT_SNAPSHOT
struct SnapShot * snapshotrecord = NULL;
struct Snapshot_t * sTheRecord = NULL;
}
#endif //nothing to initialize for the fork based snapshotting.
+/** HandlePF is the page fault handler for mprotect based snapshotting
+ * algorithm.
+ */
+
void HandlePF( int sig, siginfo_t *si, void * unused){
#if USE_MPROTECT_SNAPSHOT
if( si->si_code == SEGV_MAPERR ){
exit( EXIT_FAILURE );
}
void* addr = ReturnPageAlignedAddress(si->si_addr);
+
unsigned int backingpage=snapshotrecord->lastBackingPage++; //Could run out of pages...
if (backingpage==snapshotrecord->maxBackingPages) {
printf("Out of backing pages at %p\n", si->si_addr);
#endif //nothing to handle for non snapshotting case.
}
-//Return a page aligned address for the address being added
-//as a side effect the numBytes are also changed.
+/** ReturnPageAlignedAddress returns a page aligned address for the
+ * address being added as a side effect the numBytes are also changed.
+ */
+
void * ReturnPageAlignedAddress(void * addr) {
return (void *)(((uintptr_t)addr)&~(PAGESIZE-1));
}
-//Return a page aligned address for the address being added
-//as a side effect the numBytes are also changed.
+/** PageAlignedAdressUpdate return a page aligned address for the
+ * address being added as a side effect the numBytes are also changed.
+ */
+
void * PageAlignAddressUpward(void * addr) {
return (void *)((((uintptr_t)addr)+PAGESIZE-1)&~(PAGESIZE-1));
}
sTheRecord->mStackSize = STACK_SIZE_DEFAULT;
sTheRecord->mIDToRollback = -1;
sTheRecord->currSnapShotID = 0;
+ sTheRecord->mbFinalize = false;
#endif
}
#ifdef __cplusplus
}
#endif
+
+/** The initSnapShotLibrary function initializes the Snapshot library.
+ * @param entryPoint the function that should run the program.
+ */
void initSnapShotLibrary(unsigned int numbackingpages,
unsigned int numsnapshots, unsigned int nummemoryregions,
unsigned int numheappages, VoidFuncPtr entryPoint) {
sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART | SA_ONSTACK;
sigemptyset( &sa.sa_mask );
sa.sa_sigaction = HandlePF;
+#ifdef MAC
+ if( sigaction( SIGBUS, &sa, NULL ) == -1 ){
+ printf("SIGACTION CANNOT BE INSTALLED\n");
+ exit(EXIT_FAILURE);
+ }
+#endif
if( sigaction( SIGSEGV, &sa, NULL ) == -1 ){
printf("SIGACTION CANNOT BE INSTALLED\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
+
initSnapShotRecord(numbackingpages, numsnapshots, nummemoryregions);
// EVIL HACK: We need to make sure that calls into the HandlePF method don't cause dynamic links
// 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);
snapshotrecord->lastBackingPage--; //remove the fake page we copied
addMemoryRegionToSnapShot(pagealignedbase, numheappages);
entryPoint();
#else
- //add a signal to indicate that the process is going to terminate.
- struct sigaction sa;
- sa.sa_flags = SA_SIGINFO | SA_NODEFER | SA_RESTART;
- sigemptyset( &sa.sa_mask );
- sa.sa_sigaction = HandlePF;
- if( sigaction( SIGUSR1, &sa, NULL ) == -1 ){
- printf("SIGACTION CANNOT BE INSTALLED\n");
- exit(-1);
- }
+
+ basemySpace=system_malloc((numheappages+1)*PAGESIZE);
+ void * pagealignedbase=PageAlignAddressUpward(basemySpace);
+ mySpace = create_mspace_with_base(pagealignedbase, numheappages*PAGESIZE, 1 );
createSharedLibrary();
//step 2 setup the stack context.
} while( -1 == retVal && errno == EINTR );
if( sTheRecord->mIDToRollback != snapshotid )
- exit(0);
+ exit(EXIT_SUCCESS);
else{
swapContext = true;
}
#endif
}
-/* This function assumes that addr is page aligned */
+
+/** The addMemoryRegionToSnapShot function assumes that addr is page aligned.
+ */
void addMemoryRegionToSnapShot( void * addr, unsigned int numPages) {
#if USE_MPROTECT_SNAPSHOT
unsigned int memoryregion=snapshotrecord->lastRegion++;
if (memoryregion==snapshotrecord->maxRegions) {
printf("Exceeded supported number of memory regions!\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
snapshotrecord->regionsToSnapShot[ memoryregion ].basePtr=addr;
snapshotrecord->regionsToSnapShot[ memoryregion ].sizeInPages=numPages;
#endif //NOT REQUIRED IN THE CASE OF FORK BASED SNAPSHOTS.
}
-//take snapshot
+
+/** The takeSnapshot function takes a snapshot.
+ * @return The snapshot identifier.
+ */
+
snapshot_id takeSnapshot( ){
#if USE_MPROTECT_SNAPSHOT
for(unsigned int region=0; region<snapshotrecord->lastRegion;region++) {
if( mprotect(snapshotrecord->regionsToSnapShot[region].basePtr, snapshotrecord->regionsToSnapShot[region].sizeInPages*sizeof(struct SnapShotPage), PROT_READ ) == -1 ){
perror("mprotect");
printf("Failed to mprotect inside of takeSnapShot\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
}
unsigned int snapshot=snapshotrecord->lastSnapShot++;
if (snapshot==snapshotrecord->maxSnapShots) {
printf("Out of snapshots\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
snapshotrecord->snapShots[snapshot].firstBackingPage=snapshotrecord->lastBackingPage;
return snapshotid;
#endif
}
+
+/** The rollBack function rollback to the given snapshot identifier.
+ * @param theID is the snapshot identifier to rollback to.
+ */
+
void rollBack( snapshot_id theID ){
#if USE_MPROTECT_SNAPSHOT
std::map< void *, bool, std::less< void * >, MyAlloc< std::pair< const void *, bool > > > duplicateMap;
if( mprotect(snapshotrecord->regionsToSnapShot[region].basePtr, snapshotrecord->regionsToSnapShot[region].sizeInPages*sizeof(struct SnapShotPage), PROT_READ | PROT_WRITE ) == -1 ){
perror("mprotect");
printf("Failed to mprotect inside of takeSnapShot\n");
- exit(-1);
+ exit(EXIT_FAILURE);
}
}
for(unsigned int page=snapshotrecord->snapShots[theID].firstBackingPage; page<snapshotrecord->lastBackingPage; page++) {
#if SSDEBUG
DumpIntoLog( "ModelSnapshot", "Invoked rollback" );
#endif
- exit( 0 );
+ exit(EXIT_SUCCESS);
}
#endif
}
+/** The finalize method shuts down the snapshotting system. */
+
void finalize(){
#if !USE_MPROTECT_SNAPSHOT
sTheRecord->mbFinalize = true;
projects / c11tester.git / blobdiff