/*
* Test mf_hash_*() functions.
*/
static void
test_mf_hash()
{
mf_hashtab_T ht;
mf_hashitem_T *item;
blocknr_T key;
long_u i;
long_u num_buckets;
mf_hash_init(&ht);
/* insert some items and check invariants */
for (i = 0; i < TEST_COUNT; i++)
{
assert(ht.mht_count == i);
/* check that number of buckets is a power of 2 */
num_buckets = ht.mht_mask + 1;
assert(num_buckets > 0 && (num_buckets & (num_buckets - 1)) == 0);
/* check load factor */
assert(ht.mht_count <= (num_buckets << MHT_LOG_LOAD_FACTOR));
if (i < (MHT_INIT_SIZE << MHT_LOG_LOAD_FACTOR))
{
/* first expansion shouldn't have occurred yet */
assert(num_buckets == MHT_INIT_SIZE);
assert(ht.mht_buckets == ht.mht_small_buckets);
}
else
{
assert(num_buckets > MHT_INIT_SIZE);
assert(ht.mht_buckets != ht.mht_small_buckets);
}
key = index_to_key(i);
assert(mf_hash_find(&ht, key) == NULL);
/* allocate and add new item */
item = (mf_hashitem_T *)lalloc_clear(sizeof(mf_hashtab_T), FALSE);
assert(item != NULL);
item->mhi_key = key;
mf_hash_add_item(&ht, item);
assert(mf_hash_find(&ht, key) == item);
if (ht.mht_mask + 1 != num_buckets)
{
/* hash table was expanded */
assert(ht.mht_mask + 1 == num_buckets * MHT_GROWTH_FACTOR);
assert(i + 1 == (num_buckets << MHT_LOG_LOAD_FACTOR));
}
}
/* check presence of inserted items */
for (i = 0; i < TEST_COUNT; i++)
{
key = index_to_key(i);
item = mf_hash_find(&ht, key);
assert(item != NULL);
assert(item->mhi_key == key);
}
/* delete some items */
for (i = 0; i < TEST_COUNT; i++)
{
if (i % 100 < 70)
{
key = index_to_key(i);
item = mf_hash_find(&ht, key);
assert(item != NULL);
assert(item->mhi_key == key);
mf_hash_rem_item(&ht, item);
assert(mf_hash_find(&ht, key) == NULL);
mf_hash_add_item(&ht, item);
assert(mf_hash_find(&ht, key) == item);
mf_hash_rem_item(&ht, item);
assert(mf_hash_find(&ht, key) == NULL);
vim_free(item);
}
}
/* check again */
for (i = 0; i < TEST_COUNT; i++)
{
key = index_to_key(i);
item = mf_hash_find(&ht, key);
if (i % 100 < 70)
{
assert(item == NULL);
}
else
{
assert(item != NULL);
assert(item->mhi_key == key);
}
}
/* free hash table and all remaining items */
mf_hash_free_all(&ht);
}
/*
* Open an existing or new memory block file.
*
* fname: name of file to use (NULL means no file at all)
* Note: fname must have been allocated, it is not copied!
* If opening the file fails, fname is freed.
* flags: flags for open() call
*
* If fname != NULL and file cannot be opened, fail.
*
* return value: identifier for this memory block file.
*/
memfile_T *
mf_open(char_u *fname, int flags)
{
memfile_T *mfp;
off_T size;
#if defined(STATFS) && defined(UNIX) && !defined(__QNX__) && !defined(__minix)
# define USE_FSTATFS
struct STATFS stf;
#endif
if ((mfp = (memfile_T *)alloc((unsigned)sizeof(memfile_T))) == NULL)
return NULL;
if (fname == NULL) /* no file for this memfile, use memory only */
{
mfp->mf_fname = NULL;
mfp->mf_ffname = NULL;
mfp->mf_fd = -1;
}
else
{
mf_do_open(mfp, fname, flags); /* try to open the file */
/* if the file cannot be opened, return here */
if (mfp->mf_fd < 0)
{
vim_free(mfp);
return NULL;
}
}
mfp->mf_free_first = NULL; /* free list is empty */
mfp->mf_used_first = NULL; /* used list is empty */
mfp->mf_used_last = NULL;
mfp->mf_dirty = FALSE;
mfp->mf_used_count = 0;
mf_hash_init(&mfp->mf_hash);
mf_hash_init(&mfp->mf_trans);
mfp->mf_page_size = MEMFILE_PAGE_SIZE;
#ifdef FEAT_CRYPT
mfp->mf_old_key = NULL;
#endif
#ifdef USE_FSTATFS
/*
* Try to set the page size equal to the block size of the device.
* Speeds up I/O a lot.
* When recovering, the actual block size will be retrieved from block 0
* in ml_recover(). The size used here may be wrong, therefore
* mf_blocknr_max must be rounded up.
*/
if (mfp->mf_fd >= 0
&& fstatfs(mfp->mf_fd, &stf, sizeof(struct statfs), 0) == 0
&& stf.F_BSIZE >= MIN_SWAP_PAGE_SIZE
&& stf.F_BSIZE <= MAX_SWAP_PAGE_SIZE)
mfp->mf_page_size = stf.F_BSIZE;
#endif
if (mfp->mf_fd < 0 || (flags & (O_TRUNC|O_EXCL))
|| (size = vim_lseek(mfp->mf_fd, (off_T)0L, SEEK_END)) <= 0)
mfp->mf_blocknr_max = 0; /* no file or empty file */
else
mfp->mf_blocknr_max = (blocknr_T)((size + mfp->mf_page_size - 1)
/ mfp->mf_page_size);
mfp->mf_blocknr_min = -1;
mfp->mf_neg_count = 0;
mfp->mf_infile_count = mfp->mf_blocknr_max;
/*
* Compute maximum number of pages ('maxmem' is in Kbyte):
* 'mammem' * 1Kbyte / page-size-in-bytes.
* Avoid overflow by first reducing page size as much as possible.
*/
{
int shift = 10;
unsigned page_size = mfp->mf_page_size;
while (shift > 0 && (page_size & 1) == 0)
{
page_size = page_size >> 1;
--shift;
}
mfp->mf_used_count_max = (p_mm << shift) / page_size;
if (mfp->mf_used_count_max < 10)
mfp->mf_used_count_max = 10;
}
return mfp;
}
