osfmk/ipc/ipc_entry.c

86  *		Searches for an entry, given its name.
98 	ipc_entry_t entry;
105                 entry = &space->is_table[index];
106 		if (IE_BITS_GEN(entry->ie_bits) != MACH_PORT_GEN(name) ||
107 		    IE_BITS_TYPE(entry->ie_bits) == MACH_PORT_TYPE_NONE)
108 			entry = IE_NULL;
111 		entry = IE_NULL;
114 	assert((entry == IE_NULL) || IE_BITS_TYPE(entry->ie_bits));
115 	return entry;
121  *		Tries to allocate an entry out of the space.
126  *		KERN_SUCCESS		A free entry was found.
127  *		KERN_NO_SPACE		No entry allocated.
155 	 *	Initialize the new entry.  We need only
186  *		Allocate an entry out of the space.
191  *		KERN_SUCCESS		An entry was allocated.
193  *		KERN_NO_SPACE		No room for an entry in the space.
194  *		KERN_RESOURCE_SHORTAGE	Couldn't allocate memory for an entry.
226  *		Allocates/finds an entry with a specific name.
227  *		If an existing entry is returned, its type will be nonzero.
232  *		KERN_SUCCESS		Found existing entry with same name.
233  *		KERN_SUCCESS		Allocated a new entry.
254 		ipc_entry_t entry;
264 		 *		1) The entry is reserved (index 0)
265 		 *		2) The entry is inuse, for the same name
266 		 *		3) The entry is inuse, for a different name
267 		 *		4) The entry is free
274 			entry = &table[index];
277 				/* case #1 - the entry is reserved */
278 				assert(!IE_BITS_TYPE(entry->ie_bits));
279 				assert(!IE_BITS_GEN(entry->ie_bits));
282 			} else if (IE_BITS_TYPE(entry->ie_bits)) {
283 				if (IE_BITS_GEN(entry->ie_bits) == gen) {
284 					/* case #2 -- the entry is inuse, for the same name */
285 					*entryp = entry;
288 					/* case #3 -- the entry is inuse, for a different name. */
297 				 *      case #4 -- the entry is free
298 				 *	Rip the entry out of the free list.
310 				/* mark the previous entry modified - reconstructing the name */
316 				entry->ie_bits = gen;
317 				entry->ie_request = IE_REQ_NONE;
318 				*entryp = entry;
320 				assert(entry->ie_object == IO_NULL);
345  *		Deallocates an entry from a space.
355 	ipc_entry_t		entry)
362 	assert(entry->ie_object == IO_NULL);
363 	assert(entry->ie_request == IE_REQ_NONE);
366 	if (entry->ie_request != IE_REQ_NONE)
374 	if ((index < size) && (entry == &table[index])) {
375 		assert(IE_BITS_GEN(entry->ie_bits) == MACH_PORT_GEN(name));
376 		entry->ie_bits &= IE_BITS_GEN_MASK;
377 		entry->ie_next = table->ie_next;
381 		 * Nothing to do.  The entry does not match
385 		assert(entry == &table[index]);
386 		assert(IE_BITS_GEN(entry->ie_bits) == MACH_PORT_GEN(name));
388 	ipc_entry_modified(space, name, entry);
394  *		Note that an entry was modified in a space.
405 	__assert_only ipc_entry_t entry)
416 	assert(entry == &table[index]);
489 	 * we can identify the current size entry.
497 	 * size, then search for the next entry.
569 	 * have to take action on. For each entry, take a snapshot of the
570 	 * corresponding entry in the old table (so it won't change
576 		ipc_entry_t entry = &table[i];
579 		if (entry->ie_object != osnap.ie_object ||
580 		    IE_BITS_TYPE(entry->ie_bits) != IE_BITS_TYPE(osnap.ie_bits)) {
582 			if (entry->ie_object != IO_NULL &&
583 			    IE_BITS_TYPE(entry->ie_bits) == MACH_PORT_TYPE_SEND)
584 				ipc_hash_table_delete(table, size, entry->ie_object, i, entry);
586 			entry->ie_object = osnap.ie_object;
587 			entry->ie_bits = osnap.ie_bits;
588 			entry->ie_request = osnap.ie_request; /* or ie_next */
590 			if (entry->ie_object != IO_NULL &&
591 			    IE_BITS_TYPE(entry->ie_bits) == MACH_PORT_TYPE_SEND)
592 				ipc_hash_table_insert(table, size, entry->ie_object, i, entry);
594 			assert(entry->ie_object == osnap.ie_object);
595 			entry->ie_bits = osnap.ie_bits;
596 			entry->ie_request = osnap.ie_request; /* or ie_next */