astmm.c

			if (reg->cache) {
				cur->cache_len += reg->len;
			}
			++cur->count;
		}
	}

	whales_len = freed_regions_size(&whales);
	minnows_len = freed_regions_size(&minnows);
	ast_mutex_unlock(&reglock);

	/* Dump the whole list */
	for (cur = list; cur; cur = cur->next) {
		selected_len += cur->len;
		cache_len += cur->cache_len;
		count += cur->count;
		if (cur->cache_len) {
			if (fn) {
				ast_cli(a->fd, "%10u bytes (%10u cache) in %10u allocations by %20s() line %5u of %s\n",
					cur->len, cur->cache_len, cur->count, cur->name, cur->lineno, fn);
			} else {
				ast_cli(a->fd, "%10u bytes (%10u cache) in %10u allocations in file %s\n",
					cur->len, cur->cache_len, cur->count, cur->name);
			}
		} else {
			if (fn) {
				ast_cli(a->fd, "%10u bytes in %10u allocations by %20s() line %5u of %s\n",
					cur->len, cur->count, cur->name, cur->lineno, fn);
			} else {
				ast_cli(a->fd, "%10u bytes in %10u allocations in file %s\n",
					cur->len, cur->count, cur->name);
			}
		}
	}

	print_memory_show_common_stats(a->fd,
		whales_len, minnows_len, total_len,
		selected_len, cache_len, count);

	return CLI_SUCCESS;
}

static char *handle_memory_backtrace(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
	switch (cmd) {
	case CLI_INIT:
		e->command = "memory backtrace {on|off}";
		e->usage =
			"Usage: memory backtrace {on|off}\n"
			"       Enable dumping an allocation backtrace with memory diagnostics.\n"
			"       Note that saving the backtrace data for each allocation\n"
			"       can be CPU intensive.\n";
		return NULL;
	case CLI_GENERATE:
		return NULL;
	}

	if (a->argc != 3) {
		return CLI_SHOWUSAGE;
	}

	if (ast_true(a->argv[2])) {
		backtrace_enabled = 1;
	} else if (ast_false(a->argv[2])) {
		backtrace_enabled = 0;
	} else {
		return CLI_SHOWUSAGE;
	}

	ast_cli(a->fd, "The memory backtrace is: %s\n", backtrace_enabled ? "On" : "Off");

	return CLI_SUCCESS;
}

static struct ast_cli_entry cli_memory[] = {
	AST_CLI_DEFINE(handle_memory_atexit_list, "Enable memory allocations not freed at exit list."),
	AST_CLI_DEFINE(handle_memory_atexit_summary, "Enable memory allocations not freed at exit summary."),
	AST_CLI_DEFINE(handle_memory_show_allocations, "Display outstanding memory allocations"),
	AST_CLI_DEFINE(handle_memory_show_summary, "Summarize outstanding memory allocations"),
	AST_CLI_DEFINE(handle_memory_backtrace, "Enable dumping an allocation backtrace with memory diagnostics."),
};

AST_LIST_HEAD_NOLOCK(region_list, ast_region);

/*!
 * \internal
 * \brief Convert the allocated regions hash table to a list.
 *
 * \param list Fill list with the allocated regions.
 *
 * \details
 * Take all allocated regions from the regions[] and put them
 * into the list.
 *
 * \note reglock must be locked before calling.
 *
 * \note This function is destructive to the regions[] lists.
 *
 * \return Length of list created.
 */
static size_t mm_atexit_hash_list(struct region_list *list)
{
	struct ast_region *reg;
	size_t total_length;
	int idx;

	total_length = 0;
	for (idx = 0; idx < ARRAY_LEN(regions); ++idx) {
		while ((reg = regions[idx])) {
			regions[idx] = AST_LIST_NEXT(reg, node);
			AST_LIST_NEXT(reg, node) = NULL;
			AST_LIST_INSERT_HEAD(list, reg, node);
			++total_length;
		}
	}
	return total_length;
}

/*!
 * \internal
 * \brief Put the regions list into the allocated regions hash table.
 *
 * \param list List to put into the allocated regions hash table.
 *
 * \note reglock must be locked before calling.
 *
 * \return Nothing
 */
static void mm_atexit_hash_restore(struct region_list *list)
{
	struct ast_region *reg;
	int hash;

	while ((reg = AST_LIST_REMOVE_HEAD(list, node))) {
		hash = HASH(reg->data);
		AST_LIST_NEXT(reg, node) = regions[hash];
		regions[hash] = reg;
	}
}

/*!
 * \internal
 * \brief Sort regions comparision.
 *
 * \param left Region to compare.
 * \param right Region to compare.
 *
 * \retval <0 if left < right
 * \retval =0 if left == right
 * \retval >0 if left > right
 */
static int mm_atexit_cmp(struct ast_region *left, struct ast_region *right)
{
	int cmp;
	ptrdiff_t cmp_ptr;
	ssize_t cmp_size;

	/* Sort by filename. */
	cmp = strcmp(left->file, right->file);
	if (cmp) {
		return cmp;
	}

	/* Sort by line number. */
	cmp = left->lineno - right->lineno;
	if (cmp) {
		return cmp;
	}

	/* Sort by allocated size. */
	cmp_size = left->len - right->len;
	if (cmp_size) {
		if (cmp_size < 0) {
			return -1;
		}
		return 1;
	}

	/* Sort by allocated pointers just because. */
	cmp_ptr = left->data - right->data;
	if (cmp_ptr) {
		if (cmp_ptr < 0) {
			return -1;
		}
		return 1;
	}

	return 0;
}

/*!
 * \internal
 * \brief Merge the given sorted sublists into sorted order onto the end of the list.
 *
 * \param list Merge sublists onto this list.
 * \param sub1 First sublist to merge.
 * \param sub2 Second sublist to merge.
 *
 * \return Nothing
 */
static void mm_atexit_list_merge(struct region_list *list, struct region_list *sub1, struct region_list *sub2)
{
	struct ast_region *reg;

	for (;;) {
		if (AST_LIST_EMPTY(sub1)) {
			/* The remaining sublist goes onto the list. */
			AST_LIST_APPEND_LIST(list, sub2, node);
			break;
		}
		if (AST_LIST_EMPTY(sub2)) {
			/* The remaining sublist goes onto the list. */
			AST_LIST_APPEND_LIST(list, sub1, node);
			break;
		}

		if (mm_atexit_cmp(AST_LIST_FIRST(sub1), AST_LIST_FIRST(sub2)) <= 0) {
			reg = AST_LIST_REMOVE_HEAD(sub1, node);
		} else {
			reg = AST_LIST_REMOVE_HEAD(sub2, node);
		}
		AST_LIST_INSERT_TAIL(list, reg, node);
	}
}

/*!
 * \internal
 * \brief Take sublists off of the given list.
 *
 * \param list Source list to remove sublists from the beginning of list.
 * \param sub Array of sublists to fill. (Lists are empty on entry.)
 * \param num_lists Number of lists to remove from the source list.
 * \param size Size of the sublists to remove.
 * \param remaining Remaining number of elements on the source list.
 *
 * \return Nothing
 */
static void mm_atexit_list_split(struct region_list *list, struct region_list sub[], size_t num_lists, size_t size, size_t *remaining)
{
	int idx;

	for (idx = 0; idx < num_lists; ++idx) {
		size_t count;

		if (*remaining < size) {
			/* The remaining source list goes onto the sublist. */
			AST_LIST_APPEND_LIST(&sub[idx], list, node);
			*remaining = 0;
			break;
		}

		/* Take a sublist off the beginning of the source list. */
		*remaining -= size;
		for (count = size; count--;) {
			struct ast_region *reg;

			reg = AST_LIST_REMOVE_HEAD(list, node);
			AST_LIST_INSERT_TAIL(&sub[idx], reg, node);
		}
	}
}

/*!
 * \internal
 * \brief Sort the regions list using mergesort.
 *
 * \param list Allocated regions list to sort.
 * \param length Length of the list.
 *
 * \return Nothing
 */
static void mm_atexit_list_sort(struct region_list *list, size_t length)
{
	/*! Semi-sorted merged list. */
	struct region_list merged = AST_LIST_HEAD_NOLOCK_INIT_VALUE;
	/*! Sublists to merge. (Can only merge two sublists at this time.) */
	struct region_list sub[2] = {
		AST_LIST_HEAD_NOLOCK_INIT_VALUE,
		AST_LIST_HEAD_NOLOCK_INIT_VALUE
	};
	/*! Sublist size. */
	size_t size = 1;
	/*! Remaining elements in the list. */
	size_t remaining;
	/*! Number of sublist merge passes to process the list. */
	int passes;

	for (;;) {
		remaining = length;

		passes = 0;
		while (!AST_LIST_EMPTY(list)) {
			mm_atexit_list_split(list, sub, ARRAY_LEN(sub), size, &remaining);
			mm_atexit_list_merge(&merged, &sub[0], &sub[1]);
			++passes;
		}
		AST_LIST_APPEND_LIST(list, &merged, node);
		if (passes <= 1) {
			/* The list is now sorted. */
			break;
		}

		/* Double the sublist size to remove for next round. */
		size <<= 1;
	}
}

/*!
 * \internal
 * \brief List all regions currently allocated.
 *
 * \param alloced regions list.
 *
 * \return Nothing
 */
static void mm_atexit_regions_list(struct region_list *alloced)
{
	struct ast_region *reg;

	AST_LIST_TRAVERSE(alloced, reg, node) {
		astmm_log("%s %s() line %u: %u bytes%s at %p\n",
			reg->file, reg->func, reg->lineno,
			(unsigned int) reg->len, reg->cache ? " (cache)" : "", reg->data);
	}
}

/*!
 * \internal
 * \brief Summarize all regions currently allocated.
 *
 * \param alloced Sorted regions list.
 *
 * \return Nothing
 */
static void mm_atexit_regions_summary(struct region_list *alloced)
{
	struct ast_region *reg;
	struct ast_region *next;
	struct {
		unsigned int count;
		unsigned int len;
		unsigned int cache_len;
	} by_line, by_func, by_file, total;

	by_line.count = 0;
	by_line.len = 0;
	by_line.cache_len = 0;

	by_func.count = 0;
	by_func.len = 0;
	by_func.cache_len = 0;

	by_file.count = 0;
	by_file.len = 0;
	by_file.cache_len = 0;

	total.count = 0;
	total.len = 0;
	total.cache_len = 0;

	AST_LIST_TRAVERSE(alloced, reg, node) {
		next = AST_LIST_NEXT(reg, node);

		++by_line.count;
		by_line.len += reg->len;
		if (reg->cache) {
			by_line.cache_len += reg->len;
		}
		if (next && !strcmp(reg->file, next->file) && reg->lineno == next->lineno) {
			continue;
		}
		if (atexit_summary & SUMMARY_BY_LINE) {
			if (by_line.cache_len) {
				astmm_log("%10u bytes (%u in caches) in %u allocations. %s %s() line %u\n",
					by_line.len, by_line.cache_len, by_line.count, reg->file, reg->func, reg->lineno);
			} else {
				astmm_log("%10u bytes in %5u allocations. %s %s() line %u\n",
					by_line.len, by_line.count, reg->file, reg->func, reg->lineno);
			}
		}

		by_func.count += by_line.count;
		by_func.len += by_line.len;
		by_func.cache_len += by_line.cache_len;
		by_line.count = 0;
		by_line.len = 0;
		by_line.cache_len = 0;
		if (next && !strcmp(reg->file, next->file) && !strcmp(reg->func, next->func)) {
			continue;
		}
		if (atexit_summary & SUMMARY_BY_FUNC) {
			if (by_func.cache_len) {
				astmm_log("%10u bytes (%u in caches) in %u allocations. %s %s()\n",
					by_func.len, by_func.cache_len, by_func.count, reg->file, reg->func);
			} else {
				astmm_log("%10u bytes in %5u allocations. %s %s()\n",
					by_func.len, by_func.count, reg->file, reg->func);
			}
		}

		by_file.count += by_func.count;
		by_file.len += by_func.len;
		by_file.cache_len += by_func.cache_len;
		by_func.count = 0;
		by_func.len = 0;
		by_func.cache_len = 0;
		if (next && !strcmp(reg->file, next->file)) {
			continue;
		}
		if (atexit_summary & SUMMARY_BY_FILE) {
			if (by_file.cache_len) {
				astmm_log("%10u bytes (%u in caches) in %u allocations. %s\n",
					by_file.len, by_file.cache_len, by_file.count, reg->file);
			} else {
				astmm_log("%10u bytes in %5u allocations. %s\n",
					by_file.len, by_file.count, reg->file);
			}
		}

		total.count += by_file.count;
		total.len += by_file.len;
		total.cache_len += by_file.cache_len;
		by_file.count = 0;
		by_file.len = 0;
		by_file.cache_len = 0;
	}

	if (total.cache_len) {
		astmm_log("%u bytes (%u in caches) in %u allocations.\n",
			total.len, total.cache_len, total.count);
	} else {
		astmm_log("%u bytes in %u allocations.\n", total.len, total.count);
	}
}

/*!
 * \internal
 * \brief Dump the memory allocations atexit.
 *
 * \note reglock must be locked before calling.
 *
 * \return Nothing
 */
static void mm_atexit_dump(void)
{
	struct region_list alloced_atexit = AST_LIST_HEAD_NOLOCK_INIT_VALUE;
	size_t length;

	length = mm_atexit_hash_list(&alloced_atexit);
	if (!length) {
		/* Wow!  This is amazing! */
		astmm_log("Exiting with all memory freed.\n");
		return;
	}

	mm_atexit_list_sort(&alloced_atexit, length);

	astmm_log("Exiting with the following memory not freed:\n");
	if (atexit_list) {
		mm_atexit_regions_list(&alloced_atexit);
	}
	if (atexit_summary) {
		mm_atexit_regions_summary(&alloced_atexit);
	}

	/*
	 * Put the alloced list back into regions[].
	 *
	 * We have do do this because we can get called before all other
	 * threads have terminated.
	 */
	mm_atexit_hash_restore(&alloced_atexit);
}

/*!
 * \internal
 * \return Nothing
 */
static void mm_atexit_final(void)
{
	FILE *log;

	/* Only wait if we want atexit allocation dumps. */
	if (atexit_list || atexit_summary) {
		fprintf(stderr, "Waiting 10 seconds to let other threads die.\n");
		sleep(10);
	}

	regions_check_all_fences();

	/* Flush all delayed memory free circular arrays. */
	freed_regions_flush(&whales);
	freed_regions_flush(&minnows);

	/* Peform atexit allocation dumps. */
	if (atexit_list || atexit_summary) {
		ast_mutex_lock(&reglock);
		mm_atexit_dump();
		ast_mutex_unlock(&reglock);
	}

	/* Close the log file. */
	log = mmlog;
	mmlog = NULL;
	if (log) {
		fclose(log);
	}
}

/*!
 * \brief Initialize malloc debug phase 1.
 *
 * \note Must be called first thing in main().
 *
 * \return Nothing
 */
void __ast_mm_init_phase_1(void)
{
	atexit(mm_atexit_final);
}

/*!
 * \internal
 * \return Nothing
 */
static void mm_atexit_ast(void)
{
	ast_cli_unregister_multiple(cli_memory, ARRAY_LEN(cli_memory));
}

/*!
 * \brief Initialize malloc debug phase 2.
 *
 * \return Nothing
 */
void __ast_mm_init_phase_2(void)
{
	char filename[PATH_MAX];

	ast_cli_register_multiple(cli_memory, ARRAY_LEN(cli_memory));

	snprintf(filename, sizeof(filename), "%s/mmlog", ast_config_AST_LOG_DIR);

	ast_verb(1, "Asterisk Malloc Debugger Started (see %s))\n", filename);

	mmlog = fopen(filename, "a+");
	if (mmlog) {
		fprintf(mmlog, "%ld - New session\n", (long) time(NULL));
		fflush(mmlog);
	} else {
		ast_log(LOG_ERROR, "Could not open malloc debug log file: %s\n", filename);
	}

	ast_register_cleanup(mm_atexit_ast);
}

#endif	/* defined(__AST_DEBUG_MALLOC) */