/*
 * Copyright 2013-2014 Andrew Smith - BlackArrow Ltd
 * Copyright 2015-2016 Andrew Smith
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 3 of the License, or (at your option)
 * any later version.  See COPYING for more details.
 */

#include "klist.h"

const char *tree_node_list_name = "TreeNodes";

#if LOCK_CHECK
bool disable_checks = false;
bool check_locks = true;
const char *thread_noname = "UNSET";
int next_thread_id = 0;
__thread int my_thread_id = -1;
__thread char *my_thread_name = NULL;
__thread bool my_check_locks = true;

bool auto_check_deadlocks = true;
// Must be false to start with
bool check_deadlocks = false;
__thread int my_locks[MAX_LOCKDEPTH];
__thread const char *my_locks_n[MAX_LOCKDEPTH];
__thread const char *my_locks_fl[MAX_LOCKDEPTH];
__thread const char *my_locks_f[MAX_LOCKDEPTH];
__thread int my_locks_l[MAX_LOCKDEPTH];
__thread int my_lock_level = 0;
__thread bool my_check_deadlocks = true;
#endif
// Required for cmd_stats
bool lock_check_init = false;
cklock_t lock_check_lock;
K_LISTS *all_klists;

#define _CHKLIST(_list, _name) do {\
		if (!_list) { \
			quithere(1, "%s() can't process a NULL " _name \
					KLIST_FFL, \
					__func__, KLIST_FFL_PASS); \
		} \
	} while (0);

#define CHKLIST(__list) _CHKLIST(__list, "list")

#define CHKLS(__list) _CHKLIST(__list, "list/store")

#define _CHKITEM(_item, _list, _name) do {\
		if (!_item) { \
			quithere(1, "%s() can't process a NULL %s " _name \
					KLIST_FFL, \
					__func__, _list->name, \
					KLIST_FFL_PASS); \
		} \
	} while (0);

#define CHKITEM(__item, __list) _CHKITEM(__item, __list, "item")

void _dsp_kstore(K_STORE *store, char *filename, char *msg, KLIST_FFL_ARGS)
{
	K_ITEM *item;
	FILE *stream;
	struct tm tm;
	time_t now_t;
	char stamp[128];

	if (!(store->master->dsp_func)) {
		quithere(1, "List %s has no dsp_func" KLIST_FFL,
				store->master->name, KLIST_FFL_PASS);
	}

	now_t = time(NULL);
	localtime_r(&now_t, &tm);
	snprintf(stamp, sizeof(stamp),
			"[%d-%02d-%02d %02d:%02d:%02d]",
			tm.tm_year + 1900,
			tm.tm_mon + 1,
			tm.tm_mday,
			tm.tm_hour,
			tm.tm_min,
			tm.tm_sec);

	stream = fopen(filename, "ae");
	if (!stream)
	{
		fprintf(stderr, "%s %s() failed to open '%s' (%d) %s",
				stamp, __func__, filename, errno, strerror(errno));
		return;
	}

	if (msg)
		fprintf(stream, "%s %s\n", stamp, msg);
	else
		fprintf(stream, "%s Dump of store '%s':\n", stamp, store->master->name);

	if (store->count > 0)
	{
		K_RLOCK(store->master);

		item = store->head;
		while (item)
		{
			store->master->dsp_func(item, stream);
			item = item->next;
		}
		K_RUNLOCK(store->master);

		fprintf(stream, "End\n\n");
	}
	else
		fprintf(stream, "Empty kstore\n\n");

	fclose(stream);
}

static void k_alloc_items(K_LIST *list, KLIST_FFL_ARGS)
{
	K_ITEM *item;
	void *data;
	int allocate, i;

	CHKLIST(list);

	if (list->is_store) {
		quithere(1, "List %s store can't %s()" KLIST_FFL,
				list->name, __func__, KLIST_FFL_PASS);
	}

	if (list->limit > 0 && list->total >= list->limit)
		return;

	allocate = list->allocate;
	if (list->limit > 0 && (list->total + allocate) > list->limit)
		allocate = list->limit - list->total;

	list->item_mem_count++;
	if (!(list->item_memory = realloc(list->item_memory,
					  list->item_mem_count * sizeof(*(list->item_memory))))) {
		quithere(1, "List %s item_memory failed to realloc count=%d",
				list->name, list->item_mem_count);
	}
	item = calloc(allocate, sizeof(*item));
	if (!item) {
		quithere(1, "List %s failed to calloc %d new items - total was %d, limit was %d",
				list->name, allocate, list->total, list->limit);
	}
	list->item_memory[list->item_mem_count - 1] = (void *)item;

	item[0].name = list->name;
	item[0].prev = NULL;
	item[0].next = &(item[1]);
	for (i = 1; i < allocate-1; i++) {
		item[i].name = list->name;
		item[i].prev = &item[i-1];
		item[i].next = &item[i+1];
	}
	item[allocate-1].name = list->name;
	item[allocate-1].prev = &(item[allocate-2]);
	item[allocate-1].next = NULL;

	list->head = item;
	if (list->do_tail)
		list->tail = &(item[allocate-1]);

	list->data_mem_count++;
	if (!(list->data_memory = realloc(list->data_memory,
					  list->data_mem_count * sizeof(*(list->data_memory))))) {
		quithere(1, "List %s data_memory failed to realloc count=%d",
				list->name, list->data_mem_count);
	}
	data = calloc(allocate, list->siz);
	if (!data) {
		quithere(1, "List %s failed to calloc %d new data - total was %d, limit was %d",
				list->name, allocate, list->total, list->limit);
	}
	list->data_memory[list->data_mem_count - 1] = data;

	item = list->head;
	while (item) {
		item->data = data;
		data += list->siz;
		item = item->next;
	}

	list->total += allocate;
	list->count = allocate;
	list->count_up = allocate;
}

K_STORE *_k_new_store(K_LIST *list, KLIST_FFL_ARGS)
{
	K_STORE *store;

	CHKLIST(list);

	store = calloc(1, sizeof(*store));
	if (!store)
		quithere(1, "Failed to calloc store for %s", list->name);

	store->master = list;
	store->is_store = true;
	store->lock = NULL;
	store->name = list->name;
	store->do_tail = list->do_tail;
	store->prev_store = NULL;
	// Only tracked for lists with a lock
	if (store->master->lock == NULL) {
		store->next_store = NULL;
		store->master->stores++;
	} else {
		K_WLOCK(list);
		// In the master list, next is the head
		if (list->next_store)
			list->next_store->prev_store = store;
		store->next_store = list->next_store;
		list->next_store = store;
		list->stores++;
		K_WUNLOCK(list);
	}

	return store;
}

K_LIST *_k_new_list(const char *name, size_t siz, int allocate, int limit,
		    bool do_tail, bool lock_only, bool without_lock,
		    bool local_list, const char *name2, int cull_limit,
		    KLIST_FFL_ARGS)
{
	K_LIST *list;

	if (allocate < 1)
		quithere(1, "Invalid new list %s with allocate %d must be > 0", name, allocate);

	if (limit < 0)
		quithere(1, "Invalid new list %s with limit %d must be >= 0", name, limit);

	/* after culling, the first block of items are again allocated,
	 * so there's no point culling a single block of items */
	if (cull_limit > 0 && cull_limit <= allocate)
		quithere(1, "Invalid new list %s with cull_limit %d must be > allocate (%d)", name, cull_limit, allocate);

	list = calloc(1, sizeof(*list));
	if (!list)
		quithere(1, "Failed to calloc list %s", name);

	list->master = list;
	list->is_store = false;
	list->is_lock_only = lock_only;
	list->local_list = local_list;

	if (without_lock)
		list->lock = NULL;
	else {
		list->lock = calloc(1, sizeof(*(list->lock)));
		if (!(list->lock))
			quithere(1, "Failed to calloc lock for list %s", name);

		cklock_init(list->lock);
	}

	list->name = name;
	list->name2 = name2;
	list->siz = siz;
	list->allocate = allocate;
	list->limit = limit;
	list->do_tail = do_tail;
	list->cull_limit = cull_limit;
	list->next_store = list->prev_store = NULL;

	if (!(list->is_lock_only))
		k_alloc_items(list, KLIST_FFL_PASS);

	/* Don't want to keep track of short lived (tree) lists
	 * since they wont use locking anyway */
	if (!list->local_list) {
		K_LISTS *klists;

		// not locked :P
		if (!lock_check_init) {
			quitfrom(1, file, func, line,
				 "in %s(), lock_check_lock has not been initialised!",
				 __func__);
		}

		klists = calloc(1, sizeof(*klists));
		if (!klists)
			quithere(1, "Failed to calloc klists %s", name);

		klists->klist = list;
		ck_wlock(&lock_check_lock);
		klists->next = all_klists;
		all_klists = klists;
		ck_wunlock(&lock_check_lock);
	}

	return list;
}

/*
 * Unlink and return the head of the list
 * If the list is empty:
 * 1) If it's a store - return NULL
 * 2) alloc a new list and return the head -
 *	which is NULL if the list limit has been reached
 */
K_ITEM *_k_unlink_head(K_LIST *list, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	K_ITEM *item;

	CHKLS(list);
	_LIST_WRITE(list, chklock, file, func, line);

	if (!(list->head) && !(list->is_store))
		k_alloc_items(list, KLIST_FFL_PASS);

	if (!(list->head))
		return NULL;

	item = list->head;
	list->head = item->next;
	if (list->head)
		list->head->prev = NULL;
	else {
		if (list->do_tail)
			list->tail = NULL;
	}

	item->prev = item->next = NULL;

	list->count--;

	return item;
}

// Zeros the head returned
K_ITEM *_k_unlink_head_zero(K_LIST *list, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	K_ITEM *item;

	CHKLS(list);
	_LIST_WRITE(list, chklock, file, func, line);

	item = _k_unlink_head(list, false, KLIST_FFL_PASS);

	if (item)
		memset(item->data, 0, list->siz);

	return item;
}

// Returns NULL if empty
K_ITEM *_k_unlink_tail(K_LIST *list, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	K_ITEM *item;

	CHKLS(list);
	_LIST_WRITE(list, chklock, file, func, line);

	if (!(list->do_tail)) {
		quithere(1, "List %s can't %s() - do_tail is false" KLIST_FFL,
				list->name, __func__, KLIST_FFL_PASS);
	}

	if (!(list->tail))
		return NULL;

	item = list->tail;
	list->tail = item->prev;
	if (list->tail)
		list->tail->next = NULL;
	else
		list->head = NULL;

	item->prev = item->next = NULL;

	list->count--;

	return item;
}

#define CHKCULL(_list) \
	do { \
		if (!((_list)->is_store) && !((_list)->is_lock_only) && \
		    (_list)->cull_limit > 0 && \
		    (_list)->count == (_list)->total && \
		    (_list)->total >= (_list)->cull_limit) { \
			k_cull_list(_list, file, func, line); \
		} \
	} while(0);

static void k_cull_list(K_LIST *list, KLIST_FFL_ARGS)
{
	int i;

	CHKLIST(list);
	_LIST_WRITE(list, true, file, func, line);

	if (list->is_store) {
		quithere(1, "List %s can't %s() a store" KLIST_FFL,
				list->name, __func__, KLIST_FFL_PASS);
	}

	if (list->is_lock_only) {
		quithere(1, "List %s can't %s() a lock_only" KLIST_FFL,
				list->name, __func__, KLIST_FFL_PASS);
	}

	if (list->count != list->total) {
		quithere(1, "List %s can't %s() a list in use" KLIST_FFL,
				list->name, __func__, KLIST_FFL_PASS);
	}

	for (i = 0; i < list->item_mem_count; i++)
		free(list->item_memory[i]);
	free(list->item_memory);
	list->item_memory = NULL;
	list->item_mem_count = 0;

	for (i = 0; i < list->data_mem_count; i++)
		free(list->data_memory[i]);
	free(list->data_memory);
	list->data_memory = NULL;
	list->data_mem_count = 0;

	list->total = list->count = list->count_up = 0;
	list->head = list->tail = NULL;

	list->cull_count++;

	k_alloc_items(list, KLIST_FFL_PASS);
}

void _k_add_head(K_LIST *list, K_ITEM *item, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	CHKLS(list);
	CHKITEM(item, list);
	_LIST_WRITE(list, chklock, file, func, line);

	if (item->name != list->name) {
		quithere(1, "List %s can't %s() a %s item" KLIST_FFL,
				list->name, __func__, item->name, KLIST_FFL_PASS);
	}

	if (item->prev || item->next) {
		quithere(1, "%s() added item %s still linked" KLIST_FFL,
				__func__, item->name, KLIST_FFL_PASS);
	}

	item->prev = NULL;
	item->next = list->head;
	if (list->head)
		list->head->prev = item;

	list->head = item;

	if (list->do_tail) {
		if (!(list->tail))
			list->tail = item;
	}

	list->count++;
	list->count_up++;

	CHKCULL(list);
}

/* slows it down (of course) - only for debugging
void _k_free_head(K_LIST *list, K_ITEM *item, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	CHKLS(list);
	CHKITEM(item, list);
	_LIST_WRITE(list, chklock, file, func, line);

	memset(item->data, 0xff, list->siz);
	_k_add_head(list, item, KLIST_FFL_PASS);
}
*/

void _k_add_tail(K_LIST *list, K_ITEM *item, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	CHKLS(list);
	CHKITEM(item, list);
	_LIST_WRITE(list, chklock, file, func, line);

	if (item->name != list->name) {
		quithere(1, "List %s can't %s() a %s item" KLIST_FFL,
				list->name, __func__, item->name, KLIST_FFL_PASS);
	}

	if (!(list->do_tail)) {
		quithere(1, "List %s can't %s() - do_tail is false" KLIST_FFL,
				list->name, __func__, KLIST_FFL_PASS);
	}

	if (item->prev || item->next) {
		quithere(1, "%s() added item %s still linked" KLIST_FFL,
				__func__, item->name, KLIST_FFL_PASS);
	}

	item->prev = list->tail;
	item->next = NULL;
	if (list->tail)
		list->tail->next = item;

	list->tail = item;

	if (!(list->head))
		list->head = item;

	list->count++;
	list->count_up++;

	CHKCULL(list);
}

// Insert item into the list next after 'after'
void _k_insert_after(K_LIST *list, K_ITEM *item, K_ITEM *after, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	CHKLS(list);
	CHKITEM(item, list);
	_CHKITEM(item, after, "after");
	_LIST_WRITE(list, chklock, file, func, line);

	if (item->name != list->name) {
		quithere(1, "List %s can't %s() a %s item" KLIST_FFL,
				list->name, __func__, item->name, KLIST_FFL_PASS);
	}

	if (after->name != list->name) {
		quithere(1, "List %s can't %s() a %s after" KLIST_FFL,
				list->name, __func__, item->name, KLIST_FFL_PASS);
	}

	if (item->prev || item->next) {
		quithere(1, "%s() added item %s still linked" KLIST_FFL,
				__func__, item->name, KLIST_FFL_PASS);
	}

	item->prev = after;
	item->next = after->next;
	if (item->next)
		item->next->prev = item;
	after->next = item;

	if (list->do_tail) {
		if (list->tail == after)
			list->tail = item;
	}

	list->count++;
	list->count_up++;

	// no point checking cull since this wouldn't be an _free list
}

void _k_unlink_item(K_LIST *list, K_ITEM *item, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	CHKLS(list);
	CHKITEM(item, list);
	_LIST_WRITE(list, chklock, file, func, line);

	if (item->name != list->name) {
		quithere(1, "List %s can't %s() a %s item" KLIST_FFL,
				list->name, __func__, item->name, KLIST_FFL_PASS);
	}

	if (item->prev)
		item->prev->next = item->next;

	if (item->next)
		item->next->prev = item->prev;

	if (list->head == item)
		list->head = item->next;

	if (list->do_tail) {
		if (list->tail == item)
			list->tail = item->prev;
	}

	item->prev = item->next = NULL;

	list->count--;
}

void _k_list_transfer_to_head(K_LIST *from, K_LIST *to, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	_CHKLIST(from, "from list/store");
	_CHKLIST(to, "to list/store");

	if (from->name != to->name) {
		quithere(1, "List %s can't %s() to a %s list" KLIST_FFL,
				from->name, __func__, to->name, KLIST_FFL_PASS);
	}

	// from and to are the same lock
	_LIST_WRITE(to, chklock, file, func, line);

	if (!(from->do_tail)) {
		quithere(1, "List %s can't %s() - do_tail is false" KLIST_FFL,
				from->name, __func__, KLIST_FFL_PASS);
	}

	if (!(from->head))
		return;

	if (to->head)
		to->head->prev = from->tail;
	else
		to->tail = from->tail;

	from->tail->next = to->head;
	to->head = from->head;

	from->head = from->tail = NULL;
	to->count += from->count;
	from->count = 0;
	to->count_up += from->count_up;
	from->count_up = 0;

	CHKCULL(to);
}

void _k_list_transfer_to_tail(K_LIST *from, K_LIST *to, LOCK_MAYBE bool chklock, KLIST_FFL_ARGS)
{
	_CHKLIST(from, "from list/store");
	_CHKLIST(to, "to list/store");

	if (from->name != to->name) {
		quithere(1, "List %s can't %s() to a %s list" KLIST_FFL,
				from->name, __func__, to->name, KLIST_FFL_PASS);
	}

	// from and to are the same lock
	_LIST_WRITE(to, chklock, file, func, line);

	if (!(from->do_tail)) {
		quithere(1, "List %s can't %s() - do_tail is false" KLIST_FFL,
				from->name, __func__, KLIST_FFL_PASS);
	}

	if (!(from->head))
		return;

	if (to->tail)
		to->tail->next = from->head;
	else
		to->head = from->head;

	from->head->prev = to->tail;
	to->tail = from->tail;

	from->head = from->tail = NULL;
	to->count += from->count;
	from->count = 0;
	to->count_up += from->count_up;
	from->count_up = 0;

	CHKCULL(to);
}

K_LIST *_k_free_list(K_LIST *list, KLIST_FFL_ARGS)
{
	int i;

	CHKLIST(list);

	if (list->is_store) {
		quithere(1, "List %s can't %s() a store" KLIST_FFL,
				list->name, __func__, KLIST_FFL_PASS);
	}

	for (i = 0; i < list->item_mem_count; i++)
		free(list->item_memory[i]);
	free(list->item_memory);

	for (i = 0; i < list->data_mem_count; i++)
		free(list->data_memory[i]);
	free(list->data_memory);

	if (list->lock) {
		cklock_destroy(list->lock);

		free(list->lock);
	}

	// local_list lists are not stored in all_klists
	if (!list->local_list) {
		K_LISTS *klists, *klists_prev = NULL;

		// not locked :P
		if (!lock_check_init) {
			quitfrom(1, file, func, line,
				 "in %s(), lock_check_lock has not been initialised!",
				 __func__);
		}

		ck_wlock(&lock_check_lock);
		klists = all_klists;
		while (klists && klists->klist != list) {
			klists_prev = klists;
			klists = klists->next;
		}
		if (!klists) {
			quitfrom(1, file, func, line,
				 "in %s(), list %s not in klists",
				 __func__, list->name);
		} else {
			if (klists_prev)
				klists_prev->next = klists->next;
			else
				all_klists = klists->next;
			free(klists);
		}
		ck_wunlock(&lock_check_lock);
	}

	free(list);

	return NULL;
}

K_STORE *_k_free_store(K_STORE *store, KLIST_FFL_ARGS)
{
	_CHKLIST(store, "store");

	if (!(store->is_store)) {
		quithere(1, "Store %s can't %s() the list" KLIST_FFL,
				store->name, __func__, KLIST_FFL_PASS);
	}

	if (store->master->lock == NULL)
		store->master->stores--;
	else {
		K_WLOCK(store->master);
		// unlink store from the list
		if (store->prev_store)
			store->prev_store->next_store = store->next_store;
		if (store->next_store)
			store->next_store->prev_store = store->prev_store;
		// correct the head if we are the head
		if (store->master->next_store == store)
			store->master->next_store = store->next_store;
		store->master->stores--;
		K_WUNLOCK(store->master);
	}

	free(store);

	return NULL;
}