X-Git-Url: http://plrg.eecs.uci.edu/git/?p=c11tester.git;a=blobdiff_plain;f=snapshot.cc;h=da478075c8b4f8bde0c4fdfb3bc499f44a79ace9;hp=6d6b45070b7c611699d9d14b0b620468ee173668;hb=103b2cae595a3744095dd8432b62b138f24ec9eb;hpb=bd67491a35b9a462e1775d154d3eecfe33711984

diff --git a/snapshot.cc b/snapshot.cc
index 6d6b4507..da478075 100644
--- a/snapshot.cc
+++ b/snapshot.cc
@@ -6,14 +6,12 @@
 #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.
@@ -174,12 +172,12 @@ static void mprot_snapshot_init(unsigned int numbackingpages,
 	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();
 }
@@ -247,8 +245,6 @@ static void mprot_roll_back(snapshot_id theID)
 
 #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
 
@@ -282,8 +278,10 @@ static void createSharedMemory()
 {
 	//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;
@@ -325,7 +323,7 @@ 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;
@@ -349,19 +347,19 @@ static void fork_snapshot_init(unsigned int numbackingpages,
 				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;
 		}
 	}
@@ -369,7 +367,7 @@ static void fork_snapshot_init(unsigned int numbackingpages,
 
 static snapshot_id fork_take_snapshot()
 {
-	swapcontext(&savedUserSnapshotContext, &savedSnapshotContext);
+	model_swapcontext(&savedUserSnapshotContext, &savedSnapshotContext);
 	DEBUG("TAKESNAPSHOT RETURN\n");
 	return snapshotid;
 }
@@ -398,10 +396,11 @@ 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)
 {
@@ -412,8 +411,8 @@ 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);
@@ -422,10 +421,10 @@ 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();
@@ -434,10 +433,10 @@ 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);