#include <string.h>
#include <errno.h>
#include <sys/wait.h>
-#include <ucontext.h>
#include "hashtable.h"
#include "snapshot.h"
#include "mymemory.h"
#include "common.h"
-
-#define FAILURE(mesg) { model_print("failed in the API: %s with errno relative message: %s\n", mesg, strerror(errno)); exit(EXIT_FAILURE); }
+#include "context.h"
/** PageAlignedAdressUpdate return a page aligned address for the
* address being added as a side effect the numBytes are also changed.
#else /* !USE_MPROTECT_SNAPSHOT */
-#include <ucontext.h>
-
#define SHARED_MEMORY_DEFAULT (100 * ((size_t)1 << 20)) // 100mb for the shared memory
#define STACK_SIZE_DEFAULT (((size_t)1 << 20) * 20) // 20 mb out of the above 100 mb for my stack
{
//step 1. create shared memory.
void *memMapBase = mmap(0, SHARED_MEMORY_DEFAULT + STACK_SIZE_DEFAULT, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0);
- if (MAP_FAILED == memMapBase)
- FAILURE("mmap");
+ if (memMapBase == MAP_FAILED) {
+ perror("mmap");
+ exit(EXIT_FAILURE);
+ }
//Setup snapshot record at top of free region
fork_snap = (struct fork_snapshotter *)memMapBase;
- fork_snap->mSharedMemoryBase = (void *)((uintptr_t)memMapBase + sizeof(struct fork_snapshotter));
+ fork_snap->mSharedMemoryBase = (void *)((uintptr_t)memMapBase + sizeof(*fork_snap));
fork_snap->mStackBase = (void *)((uintptr_t)memMapBase + SHARED_MEMORY_DEFAULT);
fork_snap->mStackSize = STACK_SIZE_DEFAULT;
fork_snap->mIDToRollback = -1;
{
if (!fork_snap)
createSharedMemory();
- return create_mspace_with_base((void *)(fork_snap->mSharedMemoryBase), SHARED_MEMORY_DEFAULT - sizeof(struct fork_snapshotter), 1);
+ return create_mspace_with_base((void *)(fork_snap->mSharedMemoryBase), SHARED_MEMORY_DEFAULT - sizeof(*fork_snap), 1);
}
static void fork_snapshot_init(unsigned int numbackingpages,
newContext.uc_stack.ss_size = STACK_SIZE_DEFAULT;
makecontext(&newContext, entryPoint, 0);
/* switch to a new entryPoint context, on a new stack */
- swapcontext(&savedSnapshotContext, &newContext);
+ model_swapcontext(&savedSnapshotContext, &newContext);
/* switch back here when takesnapshot is called */
pid_t forkedID = 0;
setcontext(&savedUserSnapshotContext);
}
} else {
- int status;
- int retVal;
-
- DEBUG("The process id of child is %d and the process id of this process is %d and snapshot id is %d\n",
- forkedID, getpid(), snapshotid);
-
- do {
- retVal = waitpid(forkedID, &status, 0);
- } while (-1 == retVal && errno == EINTR);
+ DEBUG("parent PID: %d, child PID: %d, snapshot ID: %d\n",
+ getpid(), forkedID, snapshotid);
+
+ while (waitpid(forkedID, NULL, 0) < 0) {
+ /* waitpid() may be interrupted */
+ if (errno != EINTR) {
+ perror("waitpid");
+ exit(EXIT_FAILURE);
+ }
+ }
- if (fork_snap->mIDToRollback != snapshotid) {
+ if (fork_snap->mIDToRollback != snapshotid)
exit(EXIT_SUCCESS);
- }
rollback = true;
}
}
static snapshot_id fork_take_snapshot()
{
- swapcontext(&savedUserSnapshotContext, &savedSnapshotContext);
+ model_swapcontext(&savedUserSnapshotContext, &savedSnapshotContext);
DEBUG("TAKESNAPSHOT RETURN\n");
return snapshotid;
}