X-Git-Url: http://plrg.eecs.uci.edu/git/?p=model-checker.git;a=blobdiff_plain;f=mymemory.cc;h=2c5adc0a84324e045d66e33332472bd8f7fd56e2;hp=891a93f0d56c6b0fb083af75701badbafdb01041;hb=8e4abe460e49ddbda202399c30dcd17c48a6a77b;hpb=322fd21c16209780d43872cc44bb68d38172eabc

diff --git a/mymemory.cc b/mymemory.cc
index 891a93f..2c5adc0 100644
--- a/mymemory.cc
+++ b/mymemory.cc
@@ -3,68 +3,187 @@
 #include "snapshotimp.h"
 #include <stdio.h>
 #include <dlfcn.h>
-#define MSPACE_SIZE ( 1 << 20 )
-#if !USE_CHECKPOINTING
+#include <unistd.h>
+#include <cstring>
+#define REQUESTS_BEFORE_ALLOC 1024
+size_t allocatedReqs[ REQUESTS_BEFORE_ALLOC ] = { 0 };
+int nextRequest = 0;
+int howManyFreed = 0;
+#if !USE_MPROTECT_SNAPSHOT
 static mspace sStaticSpace = NULL;
 #endif
 
+//SUBRAMANIAN!!! PLEASE FIX THE MALLOC/FREE/CALLOC/ETC FOR FORK-BASED APPROACH
+//YOU HAVE NOT DONE THIS!!!!!!!!!!!
+
+/** Non-snapshotting malloc for our use. */
+
 void *MYMALLOC(size_t size) {
-#if USE_CHECKPOINTING
-  static void *(*mallocp)(size_t size);
-  char *error;
-  void *ptr;
-
-  /* get address of libc malloc */
-  if (!mallocp) {
-    mallocp = ( void * ( * )( size_t ) )dlsym(RTLD_NEXT, "malloc");
-    if ((error = dlerror()) != NULL) {
-      fputs(error, stderr);
-      exit(1);
-    }
-  }
-  ptr = mallocp(size);     
-  return ptr;
+#if USE_MPROTECT_SNAPSHOT
+	static void *(*mallocp)(size_t size);
+	char *error;
+	void *ptr;
+  
+	/* get address of libc malloc */
+	if (!mallocp) {
+		mallocp = ( void * ( * )( size_t ) )dlsym(RTLD_NEXT, "malloc");
+		if ((error = dlerror()) != NULL) {
+			fputs(error, stderr);
+			exit(EXIT_FAILURE);
+		}
+	}
+	ptr = mallocp(size);     
+	return ptr;
 #else
-  if( !sTheRecord ){
-    createSharedLibrary();
-  }
-  if( NULL == sStaticSpace )
-    sStaticSpace = create_mspace_with_base( ( void * )( sTheRecord->mSharedMemoryBase ), SHARED_MEMORY_DEFAULT -sizeof( struct Snapshot_t ), 1 );
-  return mspace_malloc( sStaticSpace, size );
+	if( !sTheRecord ){
+		createSharedLibrary();
+	}
+	if( NULL == sStaticSpace )
+		sStaticSpace = create_mspace_with_base( ( void * )( sTheRecord->mSharedMemoryBase ), SHARED_MEMORY_DEFAULT -sizeof( struct Snapshot ), 1 );
+	return mspace_malloc( sStaticSpace, size );
 #endif
 }
 
+void *system_malloc( size_t size ){
+	static void *(*mallocp)(size_t size);
+	char *error;
+	void *ptr;
+
+	/* get address of libc malloc */
+	if (!mallocp) {
+		mallocp = ( void * ( * )( size_t ) )dlsym(RTLD_NEXT, "malloc");
+		if ((error = dlerror()) != NULL) {
+			fputs(error, stderr);
+			exit(EXIT_FAILURE);
+		}
+	}
+	ptr = mallocp(size);
+	return ptr;
+}
+
+void system_free( void * ptr ){
+	static void (*freep)(void *);
+	char *error;
+
+	/* get address of libc free */
+	if (!freep) {
+		freep = ( void  ( * )( void * ) )dlsym(RTLD_NEXT, "free");
+		if ((error = dlerror()) != NULL) {
+			fputs(error, stderr);
+			exit(EXIT_FAILURE);
+		}
+	}
+	freep(ptr);
+}
+
+/** Non-snapshotting free for our use. */
 void MYFREE(void *ptr) {
-#if USE_CHECKPOINTING
-  static void (*freep)(void *);
-  char *error;
-
-  /* get address of libc free */
-  if (!freep) {
-    freep = ( void  ( * )( void * ) )dlsym(RTLD_NEXT, "free");
-    if ((error = dlerror()) != NULL) {
-      fputs(error, stderr);
-      exit(1);
-    }
-  }
-  freep(ptr);
+#if USE_MPROTECT_SNAPSHOT
+	static void (*freep)(void *);
+	char *error;
+
+	/* get address of libc free */
+	if (!freep) {
+		freep = ( void  ( * )( void * ) )dlsym(RTLD_NEXT, "free");
+		if ((error = dlerror()) != NULL) {
+			fputs(error, stderr);
+			exit(EXIT_FAILURE);
+		}
+	}
+	freep(ptr);
 #else
-  mspace_free( sStaticSpace, ptr );
+	mspace_free( sStaticSpace, ptr );
 #endif
 }
+
+
+/** This global references the mspace for the snapshotting heap */
 mspace mySpace = NULL;
+
+/** This global references the unaligned memory address that was malloced for the snapshotting heap */
+void * basemySpace = NULL;
+
+/** Adding the fix for not able to allocate through a reimplemented calloc at the beginning before instantiating our allocator
+A bit circumspect about adding an sbrk. linux docs say to avoid using it... */
+
+void * HandleEarlyAllocationRequest( size_t sz ){
+	if( 0 == mySpace ){
+		void * returnAddress = sbrk( sz );
+		if( nextRequest >= REQUESTS_BEFORE_ALLOC ){
+			exit( EXIT_FAILURE );
+		}
+		allocatedReqs[ nextRequest++ ] = ( size_t )returnAddress;
+		return returnAddress;
+	}
+	return NULL;
+}
+
+/** The fact that I am not expecting more than a handful requests is implicit in my not using a binary search here*/
+
+bool DontFree( void * ptr ){
+	if( howManyFreed == nextRequest ) return false; //a minor optimization to reduce the number of instructions executed on each free call....
+	if( NULL == ptr ) return true;
+	for( int i =  nextRequest - 1; i >= 0; --i ){
+		if( allocatedReqs[ i ] ==  ( size_t )ptr ) {
+			++howManyFreed;
+			return true;
+		}
+	}
+	return false;
+}
+
+/** Snapshotting malloc implementation for user programs. */
+
 void *malloc( size_t size ) {
-  return mspace_malloc( mySpace, size );
+	void * earlyReq = HandleEarlyAllocationRequest( size );
+	if( earlyReq ) return earlyReq;
+	return mspace_malloc( mySpace, size );
 }
 
+/** Snapshotting free implementation for user programs. */
+
 void free( void * ptr ){
-  mspace_free( mySpace, ptr );
+	if( DontFree( ptr ) ) return;
+	mspace_free( mySpace, ptr );
+}
+
+/** Snapshotting realloc implementation for user programs. */
+
+void *realloc( void *ptr, size_t size ){
+	return mspace_realloc( mySpace, ptr, size );
+}
+
+/** Snapshotting calloc implementation for user programs. */
+
+void * calloc( size_t num, size_t size ){
+	void * earlyReq = HandleEarlyAllocationRequest( size * num );
+	if( earlyReq ) {
+		std::memset( earlyReq, 0, size * num );
+		return earlyReq;
+	}
+	return mspace_calloc( mySpace, num, size );
 }
 
+/** Snapshotting new operator for user programs. */
+
 void * operator new(size_t size) throw(std::bad_alloc) {
-  return MYMALLOC(size);
+	return malloc(size);
 }
 
+/** Snapshotting delete operator for user programs. */
+
 void operator delete(void *p) throw() {
-  MYFREE(p);
+	free(p);
+}
+
+/** Snapshotting new[] operator for user programs. */
+
+void * operator new[](size_t size) throw(std::bad_alloc) {
+	return malloc(size);
+}
+
+/** Snapshotting delete[] operator for user programs. */
+
+void operator delete[](void *p, size_t size) {
+	free(p);
 }