1 files changed, 416 insertions, 0 deletions
diff --git a/src/libstrongswan/collections/array.c b/src/libstrongswan/collections/array.c
new file mode 100644
index 000000000..387e2a57d
--- /dev/null
+++ b/src/libstrongswan/collections/array.c
@@ -0,0 +1,416 @@
+/*
+ * Copyright (C) 2013 Martin Willi
+ * Copyright (C) 2013 revosec AG
+ *
+ * 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 2 of the License, or (at your
+ * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ */
+
+#include "array.h"
+
+/**
+ * Data is an allocated block, with potentially unused head and tail:
+ *
+ *   "esize" each (or sizeof(void*) if esize = 0)
+ *  /-\ /-\ /-\ /-\ /-\ /-\
+ *
+ * +---------------+-------------------------------+---------------+
+ * | h | e | a | d | e | l | e | m | e | n | t | s | t | a | i | l |
+ * +---------------+-------------------------------+---------------+
+ *
+ * \--------------/ \-----------------------------/ \-------------/
+ *      unused                    used                   unused
+ *      "head"                   "count"                 "tail"
+ *
+ */
+struct array_t {
+	/** number of elements currently in array (not counting head/tail) */
+	u_int32_t count;
+	/** size of each element, 0 for a pointer based array */
+	u_int16_t esize;
+	/** allocated but unused elements at array front */
+	u_int8_t head;
+	/** allocated but unused elements at array end */
+	u_int8_t tail;
+	/** array elements */
+	void *data;
+};
+
+/** maximum number of unused head/tail elements before cleanup */
+#define ARRAY_MAX_UNUSED 32
+
+/**
+ * Get the actual size of a number of elements
+ */
+static size_t get_size(array_t *array, u_int32_t num)
+{
+	if (array->esize)
+	{
+		return array->esize * num;
+	}
+	return sizeof(void*) * num;
+}
+
+/**
+ * Increase allocated but unused tail room to at least "room"
+ */
+static void make_tail_room(array_t *array, u_int8_t room)
+{
+	if (array->tail < room)
+	{
+		array->data = realloc(array->data,
+						get_size(array, array->count + array->head + room));
+		array->tail = room;
+	}
+}
+
+/**
+ * Increase allocated but unused head room to at least "room"
+ */
+static void make_head_room(array_t *array, u_int8_t room)
+{
+	if (array->head < room)
+	{
+		u_int8_t increase = room - array->head;
+
+		array->data = realloc(array->data,
+						get_size(array, array->count + array->tail + room));
+		memmove(array->data + get_size(array, increase), array->data,
+				get_size(array, array->count + array->tail + array->head));
+		array->head = room;
+	}
+}
+
+/**
+ * Make space for an item at index using tail room
+ */
+static void insert_tail(array_t *array, int idx)
+{
+	make_tail_room(array, 1);
+	/* move up all elements after idx by one */
+	memmove(array->data + get_size(array, array->head + idx + 1),
+			array->data + get_size(array, array->head + idx),
+			get_size(array, array->count - idx));
+
+	array->tail--;
+	array->count++;
+}
+
+/**
+ * Make space for an item at index using head room
+ */
+static void insert_head(array_t *array, int idx)
+{
+	make_head_room(array, 1);
+	/* move down all elements before idx by one */
+	memmove(array->data + get_size(array, array->head - 1),
+			array->data + get_size(array, array->head),
+			get_size(array, idx));
+
+	array->head--;
+	array->count++;
+}
+
+/**
+ * Remove an item, increase tail
+ */
+static void remove_tail(array_t *array, int idx)
+{
+	/* move all items after idx one down */
+	memmove(array->data + get_size(array, idx + array->head),
+			array->data + get_size(array, idx + array->head + 1),
+			get_size(array, array->count - idx));
+	array->count--;
+	array->tail++;
+}
+
+/**
+ * Remove an item, increase head
+ */
+static void remove_head(array_t *array, int idx)
+{
+	/* move all items before idx one up */
+	memmove(array->data + get_size(array, array->head + 1),
+			array->data + get_size(array, array->head), get_size(array, idx));
+	array->count--;
+	array->head++;
+}
+
+array_t *array_create(u_int esize, u_int8_t reserve)
+{
+	array_t *array;
+
+	INIT(array,
+		.esize = esize,
+		.tail = reserve,
+	);
+	if (array->tail)
+	{
+		array->data = malloc(array->tail * array->esize);
+	}
+	return array;
+}
+
+int array_count(array_t *array)
+{
+	if (array)
+	{
+		return array->count;
+	}
+	return 0;
+}
+
+void array_compress(array_t *array)
+{
+	if (array)
+	{
+		u_int32_t tail;
+
+		tail = array->tail;
+		if (array->head)
+		{
+			memmove(array->data, array->data + get_size(array, array->head),
+					get_size(array, array->count + array->tail));
+			tail += array->head;
+			array->head = 0;
+		}
+		if (tail)
+		{
+			array->data = realloc(array->data, get_size(array, array->count));
+			array->tail = 0;
+		}
+	}
+}
+
+typedef struct {
+	/** public enumerator interface */
+	enumerator_t public;
+	/** enumerated array */
+	array_t *array;
+	/** current index +1, initialized at 0 */
+	int idx;
+} array_enumerator_t;
+
+METHOD(enumerator_t, enumerate, bool,
+	array_enumerator_t *this, void **out)
+{
+	void *pos;
+
+	if (this->idx >= this->array->count)
+	{
+		return FALSE;
+	}
+
+	pos = this->array->data +
+		  get_size(this->array, this->idx + this->array->head);
+	if (this->array->esize)
+	{
+		/* for element based arrays we return a pointer to the element */
+		*out = pos;
+	}
+	else
+	{
+		/* for pointer based arrays we return the pointer directly */
+		*out = *(void**)pos;
+	}
+	this->idx++;
+	return TRUE;
+}
+
+enumerator_t* array_create_enumerator(array_t *array)
+{
+	array_enumerator_t *enumerator;
+
+	if (!array)
+	{
+		return enumerator_create_empty();
+	}
+
+	INIT(enumerator,
+		.public = {
+			.enumerate = (void*)_enumerate,
+			.destroy = (void*)free,
+		},
+		.array = array,
+	);
+	return &enumerator->public;
+}
+
+void array_remove_at(array_t *array, enumerator_t *public)
+{
+	array_enumerator_t *enumerator = (array_enumerator_t*)public;
+
+	if (enumerator->idx)
+	{
+		array_remove(array, --enumerator->idx, NULL);
+	}
+}
+
+void array_insert_create(array_t **array, int idx, void *ptr)
+{
+	if (*array == NULL)
+	{
+		*array = array_create(0, 0);
+	}
+	array_insert(*array, idx, ptr);
+}
+
+void array_insert_enumerator(array_t *array, int idx, enumerator_t *enumerator)
+{
+	void *ptr;
+
+	while (enumerator->enumerate(enumerator, &ptr))
+	{
+		array_insert(array, idx, ptr);
+	}
+	enumerator->destroy(enumerator);
+}
+
+void array_insert(array_t *array, int idx, void *data)
+{
+	if (idx < 0 || idx <= array_count(array))
+	{
+		void *pos;
+
+		if (idx < 0)
+		{
+			idx = array_count(array);
+		}
+
+		if (array->head && !array->tail)
+		{
+			insert_head(array, idx);
+		}
+		else if (array->tail && !array->head)
+		{
+			insert_tail(array, idx);
+		}
+		else if (idx > array_count(array) / 2)
+		{
+			insert_tail(array, idx);
+		}
+		else
+		{
+			insert_head(array, idx);
+		}
+
+		pos = array->data + get_size(array, array->head + idx);
+		if (array->esize)
+		{
+			memcpy(pos, data, get_size(array, 1));
+		}
+		else
+		{
+			/* pointer based array, copy pointer value */
+			*(void**)pos = data;
+		}
+	}
+}
+
+bool array_remove(array_t *array, int idx, void *data)
+{
+	if (!array)
+	{
+		return FALSE;
+	}
+	if (idx >= 0 && idx >= array_count(array))
+	{
+		return FALSE;
+	}
+	if (idx < 0)
+	{
+		if (array_count(array) == 0)
+		{
+			return FALSE;
+		}
+		idx = array_count(array) - 1;
+	}
+	if (data)
+	{
+		memcpy(data, array->data + get_size(array, array->head + idx),
+			   get_size(array, 1));
+	}
+	if (idx > array_count(array) / 2)
+	{
+		remove_tail(array, idx);
+	}
+	else
+	{
+		remove_head(array, idx);
+	}
+	if (array->head + array->tail > ARRAY_MAX_UNUSED)
+	{
+		array_compress(array);
+	}
+	return TRUE;
+}
+
+void array_invoke(array_t *array, array_callback_t cb, void *user)
+{
+	if (array)
+	{
+		void *obj;
+		int i;
+
+		for (i = array->head; i < array->count + array->head; i++)
+		{
+			obj = array->data + get_size(array, i);
+			if (!array->esize)
+			{
+				/* dereference if we store store pointers */
+				obj = *(void**)obj;
+			}
+			cb(obj, i - array->head, user);
+		}
+	}
+}
+
+void array_invoke_offset(array_t *array, size_t offset)
+{
+	if (array)
+	{
+		void (*method)(void *data);
+		void *obj;
+		int i;
+
+		for (i = array->head; i < array->count + array->head; i++)
+		{
+			obj = array->data + get_size(array, i);
+			if (!array->esize)
+			{
+				/* dereference if we store store pointers */
+				obj = *(void**)obj;
+			}
+			method = *(void**)(obj + offset);
+			method(obj);
+		}
+	}
+}
+
+void array_destroy(array_t *array)
+{
+	if (array)
+	{
+		free(array->data);
+		free(array);
+	}
+}
+
+void array_destroy_function(array_t *array, array_callback_t cb, void *user)
+{
+	array_invoke(array, cb, user);
+	array_destroy(array);
+}
+
+void array_destroy_offset(array_t *array, size_t offset)
+{
+	array_invoke_offset(array, offset);
+	array_destroy(array);
+}