void GuardingAllocator::deallocate(void *address)
{
if (BSLS_PERFORMANCEHINT_PREDICT_UNLIKELY(0 == address)) {
BSLS_PERFORMANCEHINT_UNLIKELY_HINT;
return; // RETURN
}
const int pageSize = getSystemPageSize();
void *firstPage; // address of the first page of the allocation
void *guardPage; // address of the guard page
if (e_BEFORE_USER_BLOCK == d_guardPageLocation) {
// The memory page before the block returned to the user is protected.
firstPage = static_cast<char *>(address) - pageSize;
guardPage = firstPage;
}
else {
// The memory page after the block returned to the user is protected.
firstPage = *(void **)(static_cast<char *>(address) - OFFSET);
guardPage = *(void **)(static_cast<char *>(address) - OFFSET * 2);
}
// Unprotect the guard page and free the memory.
const int rc = systemUnprotect(guardPage, pageSize);
(void)rc;
BSLS_ASSERT_OPT(0 == rc);
systemFree(firstPage);
}
// MANIPULATORS
void *GuardingAllocator::allocate(size_type size)
{
if (BSLS_PERFORMANCEHINT_PREDICT_UNLIKELY(0 == size)) {
BSLS_PERFORMANCEHINT_UNLIKELY_HINT;
return 0; // RETURN
}
const size_type paddedSize =
bsls::AlignmentUtil::roundUpToMaximalAlignment(size);
// Adjust for additional memory needed to stash reference addresses when
// 'e_AFTER_USER_BLOCK' is in use.
const int adjustedSize = e_AFTER_USER_BLOCK == d_guardPageLocation
? paddedSize + OFFSET * 2
: paddedSize;
// Calculate the number of pages to allocate, *not* counting the guard
// page.
const int pageSize = getSystemPageSize();
const int numPages = (adjustedSize + pageSize - 1) / pageSize;
const size_type totalSize = (numPages + 1) * pageSize; // add 1 for guard
void *firstPage = systemAlloc(totalSize);
if (!firstPage) {
#ifdef BDE_BUILD_TARGET_EXC
BSLS_THROW(bsl::bad_alloc());
#else
return 0; // RETURN
#endif
}
void *userAddress; // address to return to the caller
void *guardPage; // address of the guard page for this allocation
if (e_BEFORE_USER_BLOCK == d_guardPageLocation) {
// Protect the memory page before the block returned to the user.
guardPage = firstPage;
userAddress = static_cast<char *>(firstPage) + pageSize;
}
else {
// Protect the memory page after the block returned to the user.
guardPage = static_cast<char *>(firstPage) + (numPages * pageSize);
userAddress = static_cast<char *>(guardPage) - paddedSize;
// Stash the reference addresses required by 'deallocate'.
*(void **)(static_cast<char *>(userAddress) - OFFSET) = firstPage;
*(void **)(static_cast<char *>(userAddress) - OFFSET * 2) = guardPage;
}
// Protect the guard page from read/write access.
if (0 != systemProtect(guardPage, pageSize)) {
systemFree(firstPage);
#ifdef BDE_BUILD_TARGET_EXC
BSLS_THROW(bsl::bad_alloc());
#else
return 0; // RETURN
#endif
}
return userAddress;
}
int main(int argc, char* argv[])
{
GJCType gjc;
int initFlag, dataFlag, exitFlag=FALSE;
char c[MAX_OPTION_INPUT+EXTRA_SPACES];
/* Initialise the Gloria Jean's Coffee system to a safe empty state. */
initFlag = systemInit(&gjc);
/* Populate the Gloria Jean's Coffee system with data from the data files. */
/* Uncomment this line when you are ready to use command line arguments:*/
if(argv[1]==NULL||argv[2]==NULL){
printf("No argument found\n");
exit(EXIT_SUCCESS);
}
dataFlag = loadData(&gjc, argv[1], argv[2]);
/* Testing to see if both systemInit(.) and loadData(.) are ok */
if (initFlag == FAILURE || dataFlag == FAILURE){
exit(EXIT_FAILURE);
}
/* Interactive menu providing user with access to the 9 menu options */
while(exitFlag==FALSE){
printf("Main Menu:\n");
printf("(1) Hot Drinks Summary\n");
printf("(2) Cold Drinks Summary\n");
printf("(3) Detailed Menu Report\n");
printf("(4) Add Menu Category\n");
printf("(5) Delete Menu Category\n");
printf("(6) Add Menu Item\n");
printf("(7) Delete Menu Item\n");
printf("(8) Save & Exit\n");
printf("(9) Abort\n");
printf("Select your option (1-9):");
fgets(c,MAX_OPTION_INPUT+EXTRA_SPACES,stdin);
if(c[0]=='\n'){
printf("Invalid input\n");
}else if(stringIsInRange(c,MAX_OPTION_INPUT)==FALSE){
readRestOfLine();
printf("Invalid input\n");
}else{
stripNewLine(c);
if(strcmp(c,"1")==0){
displaySummary(&gjc,HOT);
}else if(strcmp(c,"2")==0){
displaySummary(&gjc,COLD);
}else if(strcmp(c,"3")==0){
}else if(strcmp(c,"4")==0){
}else if(strcmp(c,"5")==0){
}else if(strcmp(c,"6")==0){
}else if(strcmp(c,"7")==0){
}else if(strcmp(c,"8")==0){
}else if(strcmp(c,"9")==0){
exitFlag=TRUE;
}
}
}
/* Deallocate all dynamically allocated memory. */
systemFree(&gjc);
exit(EXIT_SUCCESS);
}
