void *malloc(size_t size)
{
void *ptr;
if (start == NULL)
{
start = sbrk(0);
end = start;
}
#ifdef DEBUG
printf("start = %p, end = %p\n", start, end);
#endif
ptr = findMemory(start, end, size);
#ifdef DEBUG
printf("\nafter findMemory ptr = %p\n", ptr);
#endif
if (addMemory(start, &end, &ptr, size) == 0)
return (0);
#ifdef DEBUG
printf("\nafter addMemory ptr = %p\n", ptr);
printf("after addMemory start = %p, end = %p\n", start, end);
#endif
useMemory(ptr, end, size);
ptr += sizeof(t_metadata);
#ifdef DEBUG
printf("\n\n");
#endif
return(ptr);
}
/**
* Inserting files into the disk
* @param const char* File Name
* @param int Size of file to be inserted
* @return FileSysErrors Errors for the function that have occurred
*/
FileSysErrors createFile(const char* filename, int size)
{
FileSysErrors errors;
/* Error Checking Needed:
* • Returns DIRECTORY_FULL if maxfiles used
* • Returns DUPLICATE_NAME if there is already a file with the name
* • Returns ZERO_SIZE if size <= 0
* • Returns CREATE_FAIL if unable to find space for the file
*/
// 1. Check for simple errors before inserting
errors = createFileErrorChecking(filename, size);
if (errors != NO_ERR) {
// Exit out
return errors;
} else {
// 1. Check for full directory
//if (DirectoryEntries > MAXFILES) {
// return DIRECTORY_FULL;
//}
// 2. Check for space and position to insert into HDD
int position = findMemory(size);
if (position < 0) {
errors = CREATE_FAIL;
return errors;
} else {
// 3. Insert into directory
int count = 0;
for (count = 0; count < MAXFILES; count++) {
if (Directory[count].Size == 0) {
// Copy in data
strcpy(Directory[count].FileName, filename);
Directory[count].Start = position;
Directory[count].Size = size;
break;
}
}
// 4. Insert into Disk
for (count = 0; count < size; count++) {
// Mark positions as read
Disk[position] = 1;
// Increment the position
position++;
}
// Update stats
FilesCreated++;
// All is good, return no error
errors = NO_ERR;
return errors;
}
}
}