talloc.c

openswan

}



/*
  A talloc version of realloc. The context argument is only used if
  ptr is NULL
*/
void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *name)
{
	struct talloc_chunk *tc;
	void *new_ptr;

	/* size zero is equivalent to free() */
	if (size == 0) {
		talloc_free(ptr);
		return NULL;
	}

	if (size >= MAX_TALLOC_SIZE) {
		return NULL;
	}

	/* realloc(NULL) is equavalent to malloc() */
	if (ptr == NULL) {
		return talloc_named_const(context, size, name);
	}

	tc = talloc_chunk_from_ptr(ptr);

	/* don't allow realloc on referenced pointers */
	if (tc->refs) {
		return NULL;
	}

	/* by resetting magic we catch users of the old memory */
	tc->magic = TALLOC_MAGIC_FREE;

#if ALWAYS_REALLOC
	new_ptr = malloc(size + sizeof(*tc));
	if (new_ptr) {
		memcpy(new_ptr, tc, tc->size + sizeof(*tc));
		free(tc);
	}
#else
	new_ptr = realloc(tc, size + sizeof(*tc));
#endif
	if (!new_ptr) {	
		tc->magic = TALLOC_MAGIC; 
		return NULL; 
	}

	tc = new_ptr;
	tc->magic = TALLOC_MAGIC;
	if (tc->parent) {
		tc->parent->child = new_ptr;
	}
	if (tc->child) {
		tc->child->parent = new_ptr;
	}

	if (tc->prev) {
		tc->prev->next = tc;
	}
	if (tc->next) {
		tc->next->prev = tc;
	}

	tc->size = size;
	talloc_set_name_const(tc+1, name);

	return (void *)(tc+1);
}

/* 
   move a lump of memory from one talloc context to another return the
   ptr on success, or NULL if it could not be transferred
*/
void *talloc_steal(const void *new_ctx, const void *ptr)
{
	struct talloc_chunk *tc, *new_tc;

	if (!ptr) {
		return NULL;
	}

	if (new_ctx == NULL) {
		new_ctx = null_context;
	}

	tc = talloc_chunk_from_ptr(ptr);

	if (new_ctx == NULL) {
		if (tc->parent) {
			_TLIST_REMOVE(tc->parent->child, tc);
			if (tc->parent->child) {
				tc->parent->child->parent = tc->parent;
			}
		} else {
			if (tc->prev) tc->prev->next = tc->next;
			if (tc->next) tc->next->prev = tc->prev;
		}
		
		tc->parent = tc->next = tc->prev = NULL;
		return discard_const_p(void, ptr);
	}

	new_tc = talloc_chunk_from_ptr(new_ctx);

	if (tc == new_tc) {
		return discard_const_p(void, ptr);
	}

	if (tc->parent) {
		_TLIST_REMOVE(tc->parent->child, tc);
		if (tc->parent->child) {
			tc->parent->child->parent = tc->parent;
		}
	} else {
		if (tc->prev) tc->prev->next = tc->next;
		if (tc->next) tc->next->prev = tc->prev;
	}

	tc->parent = new_tc;
	if (new_tc->child) new_tc->child->parent = NULL;
	_TLIST_ADD(new_tc->child, tc);

	return discard_const_p(void, ptr);
}

/*
  return the total size of a talloc pool (subtree)
*/
off_t talloc_total_size(const void *ptr)
{
	off_t total = 0;
	struct talloc_chunk *c, *tc;
	
	if (ptr == NULL) {
		ptr = null_context;
	}
	if (ptr == NULL) {
		return 0;
	}

	tc = talloc_chunk_from_ptr(ptr);

	total = tc->size;
	for (c=tc->child;c;c=c->next) {
		total += talloc_total_size(c+1);
	}
	return total;
}

/*
  return the total number of blocks in a talloc pool (subtree)
*/
off_t talloc_total_blocks(const void *ptr)
{
	off_t total = 0;
	struct talloc_chunk *c, *tc = talloc_chunk_from_ptr(ptr);

	total++;
	for (c=tc->child;c;c=c->next) {
		total += talloc_total_blocks(c+1);
	}
	return total;
}

/*
  return the number of external references to a pointer
*/
static int talloc_reference_count(const void *ptr)
{
	struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
	struct talloc_reference_handle *h;
	int ret = 0;

	for (h=tc->refs;h;h=h->next) {
		ret++;
	}
	return ret;
}

/*
  report on memory usage by all children of a pointer, giving a full tree view
*/
static void talloc_report_depth(const void *ptr, FILE *f, int depth)
{
	struct talloc_chunk *c, *tc = talloc_chunk_from_ptr(ptr);

	for (c=tc->child;c;c=c->next) {
		if (c->name == TALLOC_MAGIC_REFERENCE) {
			struct talloc_reference_handle *handle = (void *)(c+1);
			const char *name2 = talloc_get_name(handle->ptr);
			fprintf(f, "%*sreference to: %s\n", depth*4, "", name2);
		} else {
			const char *name = talloc_get_name(c+1);
			fprintf(f, "%*s%-30s contains %6lu bytes in %3lu blocks (ref %d)\n", 
				depth*4, "",
				name,
				(unsigned long)talloc_total_size(c+1),
				(unsigned long)talloc_total_blocks(c+1),
				talloc_reference_count(c+1));
			talloc_report_depth(c+1, f, depth+1);
		}
	}

}

/*
  report on memory usage by all children of a pointer, giving a full tree view
*/
void talloc_report_full(const void *ptr, FILE *f)
{
	if (ptr == NULL) {
		ptr = null_context;
	}
	if (ptr == NULL) return;

	fprintf(f,"full talloc report on '%s' (total %lu bytes in %lu blocks)\n", 
		talloc_get_name(ptr), 
		(unsigned long)talloc_total_size(ptr),
		(unsigned long)talloc_total_blocks(ptr));

	talloc_report_depth(ptr, f, 1);
}

/*
  report on memory usage by all children of a pointer
*/
void talloc_report(const void *ptr, FILE *f)
{
	struct talloc_chunk *c, *tc;

	if (ptr == NULL) {
		ptr = null_context;
	}
	if (ptr == NULL) return;
       
	fprintf(f,"talloc report on '%s' (total %lu bytes in %lu blocks)\n", 
		talloc_get_name(ptr), 
		(unsigned long)talloc_total_size(ptr),
		(unsigned long)talloc_total_blocks(ptr));

	tc = talloc_chunk_from_ptr(ptr);

	for (c=tc->child;c;c=c->next) {
		fprintf(f, "\t%-30s contains %6lu bytes in %3lu blocks\n", 
			talloc_get_name(c+1),
			(unsigned long)talloc_total_size(c+1),
			(unsigned long)talloc_total_blocks(c+1));
	}

}

/*
  report on any memory hanging off the null context
*/
static void talloc_report_null(void)
{
	if (talloc_total_size(null_context) != 0) {
		talloc_report(null_context, stderr);
	}
}

/*
  report on any memory hanging off the null context
*/
static void talloc_report_null_full(void)
{
	if (talloc_total_size(null_context) != 0) {
		talloc_report_full(null_context, stderr);
	}
}

/*
  enable leak reporting on exit
*/
void talloc_enable_leak_report(void)
{
	null_context = talloc_named_const(NULL, 0, "null_context");
	atexit(talloc_report_null);
}

/*
  enable full leak reporting on exit
*/
void talloc_enable_leak_report_full(void)
{
	null_context = talloc_named_const(NULL, 0, "null_context");
	atexit(talloc_report_null_full);
}

/* 
   talloc and zero memory. 
*/
void *_talloc_zero(const void *ctx, size_t size, const char *name)
{
	void *p = talloc_named_const(ctx, size, name);

	if (p) {
		memset(p, '\0', size);
	}

	return p;
}


/*
  memdup with a talloc. 
*/
void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name)
{
	void *newp = talloc_named_const(t, size, name);

	if (newp) {
		memcpy(newp, p, size);
	}

	return newp;
}

/*
  strdup with a talloc 
*/
char *talloc_strdup(const void *t, const char *p)
{
	char *ret;
	if (!p) {
		return NULL;
	}
	ret = talloc_memdup(t, p, strlen(p) + 1);
	if (ret) {
		talloc_set_name_const(ret, ret);
	}
	return ret;
}

/*
  strndup with a talloc 
*/
char *talloc_strndup(const void *t, const char *p, size_t n)
{
	size_t len;
	char *ret;

	for (len=0; p[len] && len<n; len++) ;

	ret = _talloc(t, len + 1);
	if (!ret) { return NULL; }
	memcpy(ret, p, len);
	ret[len] = 0;
	talloc_set_name_const(ret, ret);
	return ret;
}

char *talloc_vasprintf(const void *t, const char *fmt, va_list ap)
{	
	int len;
	char *ret;
	va_list ap2;
	
	va_copy(ap2, ap);

	len = vsnprintf(NULL, 0, fmt, ap2);

	ret = _talloc(t, len+1);
	if (ret) {
		va_copy(ap2, ap);
		vsnprintf(ret, len+1, fmt, ap2);
		talloc_set_name_const(ret, ret);
	}

	return ret;
}


/*
  Perform string formatting, and return a pointer to newly allocated
  memory holding the result, inside a memory pool.
 */
char *talloc_asprintf(const void *t, const char *fmt, ...)
{
	va_list ap;
	char *ret;

	va_start(ap, fmt);
	ret = talloc_vasprintf(t, fmt, ap);
	va_end(ap);
	return ret;
}


/**
 * Realloc @p s to append the formatted result of @p fmt and @p ap,
 * and return @p s, which may have moved.  Good for gradually
 * accumulating output into a string buffer.
 **/

static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);

static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
{	
	int len, s_len;
	va_list ap2;

	va_copy(ap2, ap);

	if (s) {
		s_len = strlen(s);
	} else {
		s_len = 0;
	}
	len = vsnprintf(NULL, 0, fmt, ap2);

	s = talloc_realloc(NULL, s, s_len + len+1);
	if (!s) return NULL;

	va_copy(ap2, ap);

	vsnprintf(s+s_len, len+1, fmt, ap2);
	talloc_set_name_const(s, s);

	return s;
}

/*
  Realloc @p s to append the formatted result of @p fmt and return @p
  s, which may have moved.  Good for gradually accumulating output
  into a string buffer.
 */
char *talloc_asprintf_append(char *s, const char *fmt, ...)
{
	va_list ap;

	va_start(ap, fmt);
	s = talloc_vasprintf_append(s, fmt, ap);
	va_end(ap);
	return s;
}

/*
  alloc an array, checking for integer overflow in the array size
*/
void *talloc_array_size(const void *ctx, size_t el_size, unsigned count, const char *name)
{
	if (count >= MAX_TALLOC_SIZE/el_size) {
		return NULL;
	}
	return talloc_named_const(ctx, el_size * count, name);
}

/*
  alloc an zero array, checking for integer overflow in the array size
*/
void *_talloc_zero_array(const void *ctx, size_t el_size, unsigned count, const char *name)
{
	if (count >= MAX_TALLOC_SIZE/el_size) {
		return NULL;
	}
	return _talloc_zero(ctx, el_size * count, name);
}


/*
  realloc an array, checking for integer overflow in the array size
*/
void *talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name)
{
	if (count >= MAX_TALLOC_SIZE/el_size) {
		return NULL;
	}
	ptr = talloc_realloc(ctx, ptr, el_size * count);
	if (ptr) {
		talloc_set_name_const(ptr, name);
	}
	return ptr;
}

/*
  a function version of talloc_realloc(), so it can be passed as a function pointer
  to libraries that want a realloc function (a realloc function encapsulates
  all the basic capabilities of an allocation library, which is why this is useful)
*/
void *talloc_realloc_fn(const void *context, void *ptr, size_t size)
{
	return _talloc_realloc(context, ptr, size, NULL);
}


static void talloc_autofree(void)
{
	talloc_free(cleanup_context);
	cleanup_context = NULL;
}

/*
  return a context which will be auto-freed on exit
  this is useful for reducing the noise in leak reports
*/
void *talloc_autofree_context(void)
{
	if (cleanup_context == NULL) {
		cleanup_context = talloc_named_const(NULL, 0, "autofree_context");
		atexit(talloc_autofree);
	}
	return cleanup_context;
}