int main(int argc, char * argv[]) {
assert(argc == 3);
int fd = open(argv[1], O_RDWR);
assert(fd >= 0);
char ** fileNames = parsePath(argv[2]);
// Super * super = Super_(fd);
GroupDesc * groupDesc = Bgd_(fd);
// char buf[BLOCK_SIZE];
// for (int i = 0; i < 5; i++) {
// int ino = ialloc(fd);
// printf("allocated ino = %d\n", ino);
// }
// printBitmap(fd, (int) super->s_inodes_count,
// (int) groupDesc->bg_inode_bitmap);
// printBitmap(fd, (int) super->s_blocks_count,
// (int) groupDesc->bg_block_bitmap);
Inode * target = groupSearch(fd, fileNames, groupDesc);
if (target == NULL) {
printf("main: unable to find ");
printArray(fileNames);
} else {
inodeShow(fd, target);
}
close(fd);
return EXIT_SUCCESS;
}
static bool groupSearch(int level, int numBlocks, Block parentBlock, Block* result)
{
int parLevel = getBlockLevel(parentBlock);
if(parLevel == level - 1)
{
if(findGroupInBlock(parentBlock, numBlocks, result, NULL))
return true;
}
for(int i = 0; i < numSubblocks[parLevel]; i++)
{
Block sub = getNthSubblock(parentBlock, i);
if(getBlockStatus(sub) == SUBDIV)
{
if(groupSearch(level, numBlocks, sub, result))
return true;
}
}
return false;
}
static bool allocBlocks(int level, int numBlocks, Block* result)
{
//printf("Allocating %d blocks at level %d\n", numBlocks, level);
if(level == 0)
{
//printf(" Will attempt to find top-level group of %d blocks.\n", numBlocks);
return findTopLevelGroup(numBlocks, result);
}
//Need to find subblock(s)
//Best to worst options:
//-Use same parent block from last allocation
//-Allocate new parent block somewhere else
//-Depth-first search subdivided blocks looking for free blocks
//-Return false
//First try lastParents
int bestOvershootParent = -1;
int bestOvershoot = 0xFFFF;
int overshoot = 0;
for(int i = 0; i < PARENT_SAVES; i++)
{
if(validBlock(lastParents[level][i]))
{
if(findGroupInBlock(lastParents[level][i], numBlocks, result, &overshoot))
{
if(overshoot < bestOvershoot)
{
bestOvershoot = overshoot;
bestOvershootParent = i;
}
}
}
}
if(bestOvershootParent != -1)
{
Block use = lastParents[level][bestOvershootParent];
if(!findGroupInBlock(use, numBlocks, result, NULL))
{
//This should never ever happen
//puts("VERY FATAL ERROR: CHECK FOUND LAST_PARENT CASE");
return false;
}
//puts("Allocation successful via lastParents");
//printf("Resulting block group: ");
//printBlock(*result);
//puts("");
allocGroup(*result, numBlocks);
return true;
}
//lastParents must be updated
//If one is not yet valid, set it to a newly allocated block
//Immediately use subblocks of that new block to fulfill current request
//puts("Did not find good cached parent block.");
bool allValid = true;
Block* toReplace;
for(int i = 0; i < PARENT_SAVES; i++)
{
if(!validBlock(lastParents[level][i]))
{
allValid = false;
toReplace = &lastParents[level][i];
break;
}
}
if(!allValid)
{
bool success = replaceParentSave(toReplace, level - 1);
if(success)
{
//use *toReplace (now a fresh subdivded block) as parent
*result = getFirstSubblock(*toReplace);
allocGroup(*result, numBlocks);
//puts("Allocation successful via newParent");
return true;
}
}
else
{
int worstGroup = 100;
int worstBlock = -1;
for(int i = 0; i < PARENT_SAVES; i++)
{
int thisGroup = getMaxGroup(lastParents[level][i]);
if(thisGroup < worstGroup)
{
worstGroup = thisGroup;
worstBlock = i;
}
}
toReplace = &lastParents[level][worstBlock];
//replace worstBlock
bool success = replaceParentSave(toReplace, level - 1);
if(success)
{
*result = getFirstSubblock(*toReplace);
allocGroup(*result, numBlocks);
return true;
//puts("Allocation sucessful via new parent.");
}
}
//If here, then depth-first search for an appropriate parent block
//that isn't necesarily listed in lastParent.
Block first;
for(int i = 0; i < numSubblocks[0]; i++)
{
Block topLevel = {{i, -1, -1, -1}};
if(getBlockStatus(topLevel) == SUBDIV)
{
if(groupSearch(level, numBlocks, topLevel, &first))
{
*result = first;
allocGroup(*result, numBlocks);
return true;
//puts("Allocation successful via worst-case dfs for parent");
}
}
}
//puts("Block group allocation failed!");
return false;
}
