我编写了在 Solaris gcc 上编译的代码
对于较小的输入它也可以正常工作，并且我得到了我想要的输出。
但是，当输入较大时，我会遇到段错误，有时在我执行 malloc 的地方，有时在我执行 free 的地方。我不是要求你调试，你能看一下并告诉我我对项目进行 malloc 和 free 的方式是否存在严重错误吗？我相信代码正在破坏堆，但我很难弄清楚在哪里。这是我的学术作业，我无法在大学机器上运行 valgrind 这样的工具。
我是 C 新手，所以代码可以更好，我知道。我仍然需要改进很多东西，比如重用变量等，但我还没有完成。
我们对消息大小有限制，因此我只发布主要结构和使用的两个结构。
struct QueueElement
{
char *path_Name;
char fileType;
int index;
struct QueueElement* next;
};
struct Queue
{
struct QueueElement* head;
struct QueueElement* tail;
};
struct DirNameSlotNumberMapping
{
char *AbsoluteDirPath;
char *AbsoluteParentDirPath;
char *DirName;
int nSlotNumberOfDir;
int nSlotNumberofDot;
};
struct Stage3ADisplay
{
int nSlot;
char *Item;
char *Type;
char *AbsoluteDirPath;
char *AttributesMDHex;
char *ContentsMDHex;
int nIndex;
unsigned char attributesMD[16];
unsigned char contentsMD[16];
};
struct DirNameSlotNumberMapping **DirDataForIndex = NULL; //create structure.
struct Stage3ADisplay **Stage3ADisplayVar = NULL; //create structure.
int nDirectoriesCounter = 0;
int nStage3ARowsCounter = 0;
int main(void)
{
char *pathName,*pathName2,*pathName3;
int nMatchesFound = 0;
char *oldPathName;
char *newPathNameStore;
struct Queue* bfsQueue = NULL;
struct QueueElement* givenPath = NULL;
enum skbool boolHelper1 = skfalse;
int exit = 0;
struct Stage3ADisplay **oldSnapshot = NULL; //create structure.
struct Stage3ADisplay **newSnapshot = NULL;
struct Stage3ADisplay **TableT1FromPDF = NULL;
struct Stage3ADisplay **TableT2FromPDF = NULL;
int nTableT1FromPDFCounter = 0;
int nTableT2FromPDFCounter = 0;
int nOldSnapshotCounter = 0;
int nNewSnapshotCounter = 0;
int *Table1ArrayChangeTracker = NULL;
int *Table2ArrayChangeTracker = NULL;
struct DirNameSlotNumberMapping **DirDataForOldIndex = NULL; //create structure.
struct DirNameSlotNumberMapping **DirDataForNewIndex = NULL; //create structure.
int nDirectoriesCounterOld = 0;
int nDirectoriesCounterNew = 0;
int nIterator1 = 0,nIterator2 = 0, nIterator3 = 0,nIterator4 = 0;
int nIterator5 = 0,nIterator6 = 0,nIterator7 = 0;
int nIterator8 = 0,nIterator9 = 0,nIterator10 = 0,nIterator11 = 0;
int nIterator15 = 0, nIterator16 = 0, nIterator17 = 0;
do
{
switch (menu())
{
case 2:
printf ( "Please enter the path under which the directory is present\n" );
pathName = malloc(300*sizeof(char));
scanf("%s",pathName);
printf ( "Please enter the name of the directory\n" );
pathName2 = malloc(300*sizeof(char));
scanf("%s",pathName2);
pathName3 = malloc(strlen(pathName) + strlen(pathName2) + 1 + 1);
strcpy(pathName3,pathName);
strcat(pathName3,"/");
strcat(pathName3,pathName2);
printf ( "Please enter the filename of the earlier snap shot file\n" );
oldPathName = malloc(300*sizeof(char));
scanf("%s",oldPathName);
boolHelper1 = CheckMD5FileAndDirectoryNameSame(pathName3,oldPathName);
if(boolHelper1 == skfalse)
{
printf("\n");
printf("The snapshot file is not for this directory\n");
printf("\n");
break;
}
else
{
printf("\n");
printf("Snapshot file and Directory Name Match\n");
printf("\n");
//write code to generate snapshot for the directory given here.
bfsQueue = Queue_New();
givenPath = malloc(1*sizeof(*givenPath));
givenPath->path_Name = pathName3;
Queue_Add_Element(bfsQueue, givenPath);
//make bfsTraverse return the name of the log file created.
//this file name can be passed on as a parameter to the
//function that compares the given log file and the newly generated log file
char * newPathName = bfsTraverse(bfsQueue);
newPathNameStore = strdup(newPathName);
Queue_Free(bfsQueue);
free(bfsQueue);
printf("\n");
bfsQueue = NULL;
free(pathName);
pathName = NULL;
//get the data of the two files into two structures.
//we'll compare the two structures.
//reading data of old snapshot into structure 1
FILE* p = NULL;
p = fopen(oldPathName, "r");
if (p != NULL )
{
fscanf(p, "%*[^\n]%*c"); //the first line is the directory name, ignore it.
char text[200];
while(fgets(text, sizeof text, p))
{
//found new item in the file
oldSnapshot = (struct Stage3ADisplay **)realloc(oldSnapshot, (nOldSnapshotCounter + 1) * sizeof(struct Stage3ADisplay *)); //add one record to the structure.
oldSnapshot[nOldSnapshotCounter] = (struct Stage3ADisplay *)malloc(sizeof(struct Stage3ADisplay)); //allocate memory for the new record added.
oldSnapshot[nOldSnapshotCounter]->Item = malloc(500);
oldSnapshot[nOldSnapshotCounter]->Type = malloc(500);
oldSnapshot[nOldSnapshotCounter]->AttributesMDHex = malloc(500);
oldSnapshot[nOldSnapshotCounter]->ContentsMDHex = malloc(500);
char *tempoutput = RemoveExtraSpaces(text,' ');
char * output = Trim_Right( tempoutput,' ');
sscanf(output,"%d %s %s %d %s %s\n",&oldSnapshot[nOldSnapshotCounter]->nSlot, oldSnapshot[nOldSnapshotCounter]->Item,oldSnapshot[nOldSnapshotCounter]->Type,&oldSnapshot[nOldSnapshotCounter]->nIndex,oldSnapshot[nOldSnapshotCounter]->AttributesMDHex,oldSnapshot[nOldSnapshotCounter]->ContentsMDHex);
nOldSnapshotCounter = nOldSnapshotCounter + 1;
}
fclose(p);
}
/*logic to reverse build DirDataForOldIndex */
int nPreviousDot = 0;
for(nIterator1 = 0; nIterator1 < nOldSnapshotCounter; nIterator1++)
{
if(strcmp(oldSnapshot[nIterator1]->Item,".") == 0)
{
nPreviousDot = oldSnapshot[nIterator1]->nSlot;
nPreviousDot = nPreviousDot - 1;
}
if(strcmp(oldSnapshot[nIterator1]->Item,".") != 0 && strcmp(oldSnapshot[nIterator1]->Item,"..") != 0 && strcmp(oldSnapshot[nIterator1]->Type,"d") ==0)
{
//found a directory, add it to the directory mapper structure.
DirDataForOldIndex = (struct DirNameSlotNumberMapping **)realloc(DirDataForOldIndex, (nDirectoriesCounterOld + 1) * sizeof(struct DirDataForIndex *)); //add one student to the structure.
DirDataForOldIndex[nDirectoriesCounterOld] = (struct DirNameSlotNumberMapping *)malloc(sizeof(struct DirNameSlotNumberMapping)); //allocate memory for the new student added.
if(oldSnapshot[nIterator1]->nIndex == 0)
{
DirDataForOldIndex[nDirectoriesCounterOld]->DirName = strdup(oldSnapshot[nIterator1]->Item);
DirDataForOldIndex[nDirectoriesCounterOld]->AbsoluteDirPath = strdup(pathName3);
DirDataForOldIndex[nDirectoriesCounterOld]->AbsoluteParentDirPath = "NOPARENT";
DirDataForOldIndex[nDirectoriesCounterOld]->nSlotNumberOfDir = oldSnapshot[nIterator1]->nSlot;
DirDataForOldIndex[nDirectoriesCounterOld]->nSlotNumberofDot = oldSnapshot[nIterator1]->nSlot + 1;
}
else
{
DirDataForOldIndex[nDirectoriesCounterOld]->DirName = strdup(oldSnapshot[nIterator1]->Item);
DirDataForOldIndex[nDirectoriesCounterOld]->nSlotNumberofDot = oldSnapshot[nIterator1]->nIndex;
DirDataForOldIndex[nDirectoriesCounterOld]->nSlotNumberOfDir = oldSnapshot[nIterator1]->nSlot;
//now build the absolute and the parent dir path names.
//using the previous dot variable,get the directory under which we are located.
//get the index number of the previous dot position.
int IndexVar = oldSnapshot[nPreviousDot]->nIndex;
IndexVar = IndexVar - 1;
//get that row's item and slot number, we'll match it
char *ItemName = oldSnapshot[IndexVar]->Item;
int nSlotNumber = oldSnapshot[IndexVar]->nSlot;
//now search in the DirDataForIndex
for(nIterator2 = 0; nIterator2 < nDirectoriesCounterOld; nIterator2++)
{
if(strcmp(DirDataForOldIndex[nIterator2]->DirName,ItemName) == 0 && DirDataForOldIndex[nIterator2]->nSlotNumberOfDir == nSlotNumber)
{
//that row's absolute path is the parent of this.
DirDataForOldIndex[nDirectoriesCounterOld]->AbsoluteParentDirPath = strdup(DirDataForOldIndex[nIterator2]->AbsoluteDirPath);
char* temp = malloc(strlen(DirDataForOldIndex[nDirectoriesCounterOld]->AbsoluteParentDirPath) + strlen(DirDataForOldIndex[nDirectoriesCounterOld]->DirName) + 1 + 1);
strcpy(temp,DirDataForOldIndex[nDirectoriesCounterOld]->AbsoluteParentDirPath);
strcat(temp,"/");
strcat(temp,DirDataForOldIndex[nDirectoriesCounterOld]->DirName);
DirDataForOldIndex[nDirectoriesCounterOld]->AbsoluteDirPath = strdup(temp);
free(temp);
temp = NULL;
}
}
}
nDirectoriesCounterOld = nDirectoriesCounterOld + 1;
}
}
//reading data of new snapshot into structure 2
p = fopen(newPathName, "r");
if (p != NULL )
{
fscanf(p, "%*[^\n]%*c"); //the first line is the directory name, ignore it.
char text[200];
while(fgets(text, sizeof text, p))
{
//found new item in the file
newSnapshot = (struct Stage3ADisplay **)realloc(newSnapshot, (nNewSnapshotCounter + 1) * sizeof(struct Stage3ADisplay *)); //add one record to the structure.
newSnapshot[nNewSnapshotCounter] = (struct Stage3ADisplay *)malloc(sizeof(struct Stage3ADisplay)); //allocate memory for the new record added.
newSnapshot[nNewSnapshotCounter]->Item = malloc(500);
newSnapshot[nNewSnapshotCounter]->Type = malloc(500);
newSnapshot[nNewSnapshotCounter]->AttributesMDHex = malloc(500);
newSnapshot[nNewSnapshotCounter]->ContentsMDHex = malloc(500);
char * output = Trim_Right(RemoveExtraSpaces(text,' '),' ');
sscanf(output,"%d %s %s %d %s %s\n",&newSnapshot[nNewSnapshotCounter]->nSlot, newSnapshot[nNewSnapshotCounter]->Item,newSnapshot[nNewSnapshotCounter]->Type,&newSnapshot[nNewSnapshotCounter]->nIndex,newSnapshot[nNewSnapshotCounter]->AttributesMDHex,newSnapshot[nNewSnapshotCounter]->ContentsMDHex);
nNewSnapshotCounter = nNewSnapshotCounter + 1;
}
fclose(p);
}
/*logic to reverse build DirDataForNewIndex */
nPreviousDot = 0;
for(nIterator1 = 0; nIterator1 < nNewSnapshotCounter; nIterator1++)
{
if(strcmp(newSnapshot[nIterator1]->Item,".") == 0)
{
nPreviousDot = newSnapshot[nIterator1]->nSlot;
nPreviousDot = nPreviousDot - 1;
}
if(strcmp(newSnapshot[nIterator1]->Item,".") != 0 && strcmp(newSnapshot[nIterator1]->Item,"..") != 0 && strcmp(newSnapshot[nIterator1]->Type,"d") ==0)
{
//found a directory, add it to the directory mapper structure.
DirDataForNewIndex = (struct DirNameSlotNumberMapping **)realloc(DirDataForNewIndex, (nDirectoriesCounterNew + 1) * sizeof(struct DirDataForIndex *)); //add one student to the structure.
DirDataForNewIndex[nDirectoriesCounterNew] = (struct DirNameSlotNumberMapping *)malloc(sizeof(struct DirNameSlotNumberMapping)); //allocate memory for the new student added.
if(newSnapshot[nIterator1]->nIndex == 0)
{
DirDataForNewIndex[nDirectoriesCounterNew]->DirName = strdup(newSnapshot[nIterator1]->Item);
DirDataForNewIndex[nDirectoriesCounterNew]->AbsoluteDirPath = strdup(pathName3);
DirDataForNewIndex[nDirectoriesCounterNew]->AbsoluteParentDirPath = "NOPARENT";
DirDataForNewIndex[nDirectoriesCounterNew]->nSlotNumberOfDir = newSnapshot[nIterator1]->nSlot;
DirDataForNewIndex[nDirectoriesCounterNew]->nSlotNumberofDot = newSnapshot[nIterator1]->nSlot + 1;
}
else
{
DirDataForNewIndex[nDirectoriesCounterNew]->DirName = strdup(newSnapshot[nIterator1]->Item);
DirDataForNewIndex[nDirectoriesCounterNew]->nSlotNumberofDot = newSnapshot[nIterator1]->nIndex;
DirDataForNewIndex[nDirectoriesCounterNew]->nSlotNumberOfDir = newSnapshot[nIterator1]->nSlot;
//now build the absolute and the parent dir path names.
//using the previous dot variable,get the directory under which we are located.
//get the index number of the previous dot position.
int IndexVar = newSnapshot[nPreviousDot]->nIndex;
IndexVar = IndexVar - 1;
//get that row's item and slot number, we'll match it
char *ItemName = newSnapshot[IndexVar]->Item;
int nSlotNumber = newSnapshot[IndexVar]->nSlot;
//now search in the DirDataFornewIndex
for(nIterator2 = 0; nIterator2 < nDirectoriesCounterNew; nIterator2++)
{
if(strcmp(DirDataForNewIndex[nIterator2]->DirName,ItemName) == 0 && DirDataForNewIndex[nIterator2]->nSlotNumberOfDir == nSlotNumber)
{
//that row's absolute path is the parent of this.
DirDataForNewIndex[nDirectoriesCounterNew]->AbsoluteParentDirPath = strdup(DirDataForNewIndex[nIterator2]->AbsoluteDirPath);
char* temp = malloc(strlen(DirDataForNewIndex[nDirectoriesCounterNew]->AbsoluteParentDirPath) + strlen(DirDataForNewIndex[nDirectoriesCounterNew]->DirName) + 1 + 1);
strcpy(temp,DirDataForNewIndex[nDirectoriesCounterNew]->AbsoluteParentDirPath);
strcat(temp,"/");
strcat(temp,DirDataForNewIndex[nDirectoriesCounterNew]->DirName);
DirDataForNewIndex[nDirectoriesCounterNew]->AbsoluteDirPath = strdup(temp);
free(temp);
temp = NULL;
}
}
}
nDirectoriesCounterNew = nDirectoriesCounterNew + 1;
}
}
//now we have reverse built DirDataForOldIndex and DirDataForNewIndex.
Table1ArrayChangeTracker = realloc(Table1ArrayChangeTracker,(nDirectoriesCounterOld + 1)*sizeof(int));
Table2ArrayChangeTracker = realloc(Table2ArrayChangeTracker,(nDirectoriesCounterNew + 1)*sizeof(int));
for(nIterator4 = 0; nIterator4 < nDirectoriesCounterOld; nIterator4++)
{
Table1ArrayChangeTracker[nIterator4] = -1; //initialize to -1
}
for(nIterator4 = 0; nIterator4 < nDirectoriesCounterNew; nIterator4++)
{
Table2ArrayChangeTracker[nIterator4] = -1; //initialize to -1
}
//get blocks one by one from the nDirectoriesCounterOld
for(nIterator4 = 0; nIterator4 < nDirectoriesCounterOld; nIterator4++)
{
char *absoluteDirectoryPath = DirDataForOldIndex[nIterator4]->AbsoluteDirPath;
int dot = DirDataForOldIndex[nIterator4]->nSlotNumberofDot;
int nexthighestdot = 0;
if(nIterator4 == nDirectoriesCounterOld - 1)
{
nexthighestdot = nOldSnapshotCounter;
nexthighestdot = nexthighestdot - 1;
}
else
{
nexthighestdot = DirDataForOldIndex[nIterator4 + 1]->nSlotNumberofDot;
nexthighestdot = nexthighestdot - 1;
nexthighestdot = nexthighestdot - 1;
}
//now, we have a block from dot to nexthighestdot.
//for referenceing the oldSnapshot
dot = dot - 1;
for(nIterator7 = dot; nIterator7 <= nexthighestdot;nIterator7++)
{
TableT1FromPDF = (struct Stage3ADisplay **)realloc(TableT1FromPDF, (nTableT1FromPDFCounter + 1) * sizeof(struct Stage3ADisplay *)); //add one record to the structure.
TableT1FromPDF[nTableT1FromPDFCounter] = (struct Stage3ADisplay *)malloc(sizeof(struct Stage3ADisplay)); //allocate memory for the new record added.
TableT1FromPDF[nTableT1FromPDFCounter]->nSlot = oldSnapshot[nIterator7]->nSlot;
TableT1FromPDF[nTableT1FromPDFCounter]->Item = malloc(strlen(oldSnapshot[nIterator7]->Item) + 1);
strcpy(TableT1FromPDF[nTableT1FromPDFCounter]->Item,oldSnapshot[nIterator7]->Item);
TableT1FromPDF[nTableT1FromPDFCounter]->Type = malloc(strlen(oldSnapshot[nIterator7]->Type) + 1);
strcpy(TableT1FromPDF[nTableT1FromPDFCounter]->Type,oldSnapshot[nIterator7]->Type);
TableT1FromPDF[nTableT1FromPDFCounter]->nIndex = oldSnapshot[nIterator7]->nIndex;
TableT1FromPDF[nTableT1FromPDFCounter]->AttributesMDHex = malloc(strlen(oldSnapshot[nIterator7]->AttributesMDHex) + 1);
strcpy(TableT1FromPDF[nTableT1FromPDFCounter]->AttributesMDHex,oldSnapshot[nIterator7]->AttributesMDHex);
TableT1FromPDF[nTableT1FromPDFCounter]->ContentsMDHex = malloc(strlen(oldSnapshot[nIterator7]->ContentsMDHex) + 1);
strcpy(TableT1FromPDF[nTableT1FromPDFCounter]->ContentsMDHex,oldSnapshot[nIterator7]->ContentsMDHex);
nTableT1FromPDFCounter = nTableT1FromPDFCounter + 1;
}
//now search for the same block in the newSnapshot
for(nIterator6 = 0; nIterator6 < nDirectoriesCounterNew; nIterator6++)
{
if(strcmp(absoluteDirectoryPath,DirDataForNewIndex[nIterator6]->AbsoluteDirPath) == 0)
{
//found the corresponding directory in the second block.
int dot2 = DirDataForNewIndex[nIterator6]->nSlotNumberofDot;
int nexthighestdot2 = 0;
if(nIterator6 == nDirectoriesCounterNew - 1)
{
nexthighestdot2 = nOldSnapshotCounter;
nexthighestdot2 = nexthighestdot2 - 1;
}
else
{
nexthighestdot2 = DirDataForNewIndex[nIterator6 + 1]->nSlotNumberofDot;
nexthighestdot2 = nexthighestdot2 - 1;
nexthighestdot2 = nexthighestdot2 - 1;
}
dot2 = dot2 - 1;
for(nIterator9 = dot2;nIterator9 <= nexthighestdot2; nIterator9++)
{
TableT2FromPDF = (struct Stage3ADisplay **)realloc(TableT2FromPDF, (nTableT2FromPDFCounter + 1) * sizeof(struct Stage3ADisplay *)); //add one record to the structure.
TableT2FromPDF[nTableT2FromPDFCounter] = (struct Stage3ADisplay *)malloc(sizeof(struct Stage3ADisplay)); //allocate memory for the new record added.
TableT2FromPDF[nTableT2FromPDFCounter]->nSlot = newSnapshot[nIterator9]->nSlot;
TableT2FromPDF[nTableT2FromPDFCounter]->Item = malloc(strlen(newSnapshot[nIterator9]->Item) + 1);
strcpy(TableT2FromPDF[nTableT2FromPDFCounter]->Item,newSnapshot[nIterator9]->Item);
TableT2FromPDF[nTableT2FromPDFCounter]->Type = malloc(strlen(newSnapshot[nIterator9]->Type) + 1);
strcpy(TableT2FromPDF[nTableT2FromPDFCounter]->Type,newSnapshot[nIterator9]->Type);
TableT2FromPDF[nTableT2FromPDFCounter]->nIndex = newSnapshot[nIterator9]->nIndex;
TableT2FromPDF[nTableT2FromPDFCounter]->AttributesMDHex = malloc(strlen(newSnapshot[nIterator9]->AttributesMDHex) + 1);
strcpy(TableT2FromPDF[nTableT2FromPDFCounter]->AttributesMDHex,newSnapshot[nIterator9]->AttributesMDHex);
TableT2FromPDF[nTableT2FromPDFCounter]->ContentsMDHex = malloc(strlen(newSnapshot[nIterator9]->ContentsMDHex) + 1);
strcpy(TableT2FromPDF[nTableT2FromPDFCounter]->ContentsMDHex,newSnapshot[nIterator9]->ContentsMDHex);
nTableT2FromPDFCounter = nTableT2FromPDFCounter + 1;
}
break;
}
}
//now we have the matching blocks, start comparing
for(nIterator10 = 0; nIterator10 < nTableT1FromPDFCounter; nIterator10++)
{
for(nIterator11 = 0; nIterator11 < nTableT2FromPDFCounter; nIterator11++)
{
enum skbool bAttributesChanged = skfalse;
enum skbool bContentsChanged = skfalse;
if(strcmp(TableT1FromPDF[nIterator10]->Item,TableT2FromPDF[nIterator11]->Item) == 0)
{
//matching element found in both arrays.
//compare attribute digest and message digests.
if(strcmp(TableT1FromPDF[nIterator10]->AttributesMDHex,TableT2FromPDF[nIterator11]->AttributesMDHex) == 0 && strcmp(TableT1FromPDF[nIterator10]->ContentsMDHex,TableT2FromPDF[nIterator11]->ContentsMDHex) == 0)
{
Table1ArrayChangeTracker[TableT1FromPDF[nIterator10]->nSlot - 1] = 1;
Table2ArrayChangeTracker[TableT2FromPDF[nIterator11]->nSlot - 1] = 1;
nMatchesFound++;
}
else
{
Table1ArrayChangeTracker[TableT1FromPDF[nIterator10]->nSlot - 1] = 2;
Table2ArrayChangeTracker[TableT2FromPDF[nIterator11]->nSlot - 1] = 2;
}
}
}
}
//after comparing clear temporary tables.
int nIterator99;
for(nIterator99 = 0; nIterator99 < nTableT1FromPDFCounter; nIterator99++)
{
free(TableT1FromPDF[nIterator99]->Item);
(TableT1FromPDF[nIterator99]->Item) = NULL;
free(TableT1FromPDF[nIterator99]->Type);
TableT1FromPDF[nIterator99]->Type = NULL;
free(TableT1FromPDF[nIterator99]->AttributesMDHex);
TableT1FromPDF[nIterator99]->AttributesMDHex = NULL;
free(TableT1FromPDF[nIterator99]->ContentsMDHex);
TableT1FromPDF[nIterator99]->ContentsMDHex = NULL;
free(TableT1FromPDF[nIterator99]);
TableT1FromPDF[nIterator99] = NULL;
}
for(nIterator99 = 0; nIterator99 < nTableT2FromPDFCounter; nIterator99++)
{
free(TableT2FromPDF[nIterator99]->Item);
TableT2FromPDF[nIterator99]->Item = NULL;
free(TableT2FromPDF[nIterator99]->Type);
TableT2FromPDF[nIterator99]->Type = NULL;
free(TableT2FromPDF[nIterator99]->AttributesMDHex);
TableT2FromPDF[nIterator99]->AttributesMDHex = NULL;
free(TableT2FromPDF[nIterator99]->ContentsMDHex);
TableT2FromPDF[nIterator99]->ContentsMDHex = NULL;
free(TableT2FromPDF[nIterator99]);
TableT2FromPDF[nIterator99] = NULL;
}
free(TableT1FromPDF);
free(TableT2FromPDF);
nTableT1FromPDFCounter = 0;
nTableT2FromPDFCounter = 0;
TableT1FromPDF = NULL;
TableT2FromPDF = NULL;
}
}
nMatchesFound++;
printf("Total matches found is %d\n",nMatchesFound);
nMatchesFound = 0;
free(oldSnapshot);
free(newSnapshot);
free(DirDataForOldIndex);
free(DirDataForNewIndex);
free(pathName3);
free(oldPathName);
free(Table1ArrayChangeTracker);
free(Table2ArrayChangeTracker);
nOldSnapshotCounter = 0;
nNewSnapshotCounter = 0;
nDirectoriesCounterOld = 0;
nDirectoriesCounterNew = 0;
Table1ArrayChangeTracker = NULL;
Table2ArrayChangeTracker = NULL;
oldSnapshot = NULL;
newSnapshot = NULL;
DirDataForOldIndex = NULL;
DirDataForNewIndex = NULL;
pathName3 = NULL;
oldPathName = NULL;
if(newPathNameStore != NULL)
{
printf("Snapshot file with name %s created\n",newPathNameStore);
free(newPathNameStore);
newPathNameStore = NULL;
}
int nIterator66;
for(nIterator66 = 0; nIterator66 < nDirectoriesCounter; nIterator66++)
{
free(DirDataForIndex[nIterator66]);
DirDataForIndex[nIterator66] = NULL;
}
free(DirDataForIndex);
for(nIterator66 = 0; nIterator66 < nStage3ARowsCounter; nIterator66++)
{
free(Stage3ADisplayVar[nIterator66]);
Stage3ADisplayVar[nIterator66]= NULL;
}
free(Stage3ADisplayVar);
nDirectoriesCounter = 0;
nStage3ARowsCounter = 0;
DirDataForIndex = NULL;
Stage3ADisplayVar = NULL;
break;
case 3:
printf ( "Exiting!\n" );
exit = 1;
break;
}
}while(exit == 0);
return 0;
}
最佳答案
我建议的一件事是检查 malloc 之后和 free 之前的状态，如下所示
char *temp = malloc(10);
if(temp == NULL) {
//Malloc failed handle it
}
和
编辑:这是不必要的，因为誓言指出 free(NULL); 是一个无操作
if(temp != NULL) {
free(temp);
temp = NULL;
}
关于c - 改进我执行 malloc 和 free 的方式，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/9930030/