toxcore/toxcore/misc_tools.h
2013-10-24 16:37:39 -04:00

290 lines
8.2 KiB
C

/* misc_tools.h
*
* Miscellaneous functions and data structures for doing random things.
*
* Copyright (C) 2013 Tox project All Rights Reserved.
*
* This file is part of Tox.
*
* Tox 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.
*
* Tox 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.
*
* You should have received a copy of the GNU General Public License
* along with Tox. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef MISC_TOOLS_H
#define MISC_TOOLS_H
#include <stdlib.h>
#include <stdint.h>
#include <string.h> /* for memcpy() */
/*********************Debugging Macros********************
* wiki.tox.im/index.php/Internal_functions_and_data_structures#Debugging
*********************************************************/
#ifdef DEBUG
#include <assert.h>
#include <stdio.h>
#include <string.h>
#define DEBUG_PRINT(str, ...) do { \
char msg[1000]; \
sprintf(msg, "%s(): line %d (file %s): %s%%c\n", __FUNCTION__, __LINE__, __FILE__, str); \
fprintf(stderr, msg, __VA_ARGS__); \
} while (0)
#define WARNING(...) do { \
fprintf(stderr, "warning in "); \
DEBUG_PRINT(__VA_ARGS__, ' '); \
} while (0)
#define INFO(...) do { \
DEBUG_PRINT(__VA_ARGS__, ' '); \
} while (0)
#undef ERROR
#define ERROR(exit_status, ...) do { \
fprintf(stderr, "error in "); \
DEBUG_PRINT(__VA_ARGS__, ' '); \
exit(exit_status); \
} while (0)
#else
#define WARNING(...)
#define INFO(...)
#undef ERROR
#define ERROR(...)
#endif // DEBUG
/************************Linked List***********************
* http://wiki.tox.im/index.php/Internal_functions_and_data_structures#Linked_List
* TODO: Update wiki.
**********************************************************/
/* Example usage
This sample program makes a new struct which contains a
character and a tox_list_t. It then prompts a user for
input until he enters q or e. It then adds each character
to the list, and uses a special for loop to print them.
It then removes all the 'z' characters, and prints the list
again.
//Notice that the data to be put in the list *contains* tox_list_t;
//usually, this is the other way around!
typedef struct tox_string {
char c;
tox_list_t tox_lst; //Notice that tox_lst is *NOT* a pointer.
} tox_string_t;
int main()
{
tox_list_t head;
tox_list_new(&head); //initialize head
//input a new character, until user enters q or e
char c = '\0';
while (c != 'q' && c != 'e') {
scanf("%c", &c);
tox_string_t* tmp = malloc(sizeof(tox_string_t));
tmp->c = c;
tox_list_add(&head, &tmp->tox_lst); //add it to the list
}
TOX_LIST_FOR_EACH() takes a struct tox_list and a name for a temporary pointer to use in the loop.
TOX_LIST_GET_VALUE() uses magic to return an instance of a structure that contains tox_list_t.
You have to give it a temporary tox_string_t, name of tox_list_t member inside our structure (tox_lst),
and the type of structure to return.
TOX_LIST_FOR_EACH(head, tmp)
printf("%c", TOX_LIST_GET_VALUE(*tmp, tox_lst, tox_string_t).c);
TOX_LIST_FOR_EACH(head, tmp) {
if (TOX_LIST_GET_VALUE(*tmp, tox_lst, tox_string_t).c == 'z') {
//If you delete tmp, you have to quit the loop, or it will go on infinitly.
//This will be fixed later on.
tox_list_remove(tmp);
break;
}
}
printf("\n");
TOX_LIST_FOR_EACH(head, tmp)
printf("%c", TOX_LIST_GET_VALUE(*tmp, tox_lst, tox_string_t).c);
return 0;
}
*/
#define MEMBER_OFFSET(var_name_in_parent, parent_type) \
(&(((parent_type*)0)->var_name_in_parent))
#define GET_PARENT(var, var_name_in_parent, parent_type) \
((parent_type*)((uint64_t)(&(var)) - (uint64_t)(MEMBER_OFFSET(var_name_in_parent, parent_type))))
#define TOX_LIST_FOR_EACH(lst, tmp_name) \
for (tox_list* tmp_name = lst.next; tmp_name != &lst; tmp_name = tmp_name->next)
#define TOX_LIST_GET_VALUE(tmp_name, name_in_parent, parent_type) GET_PARENT(tmp_name, name_in_parent, parent_type)
typedef struct tox_list {
struct tox_list *prev, *next;
} tox_list;
/* return new tox_list_t. */
static inline void tox_list_new(tox_list *lst)
{
lst->prev = lst->next = lst;
}
/* Inserts a new tox_lst after lst and returns it. */
static inline void tox_list_add(tox_list *lst, tox_list *new_lst)
{
tox_list_new(new_lst);
new_lst->next = lst->next;
new_lst->next->prev = new_lst;
lst->next = new_lst;
new_lst->prev = lst;
}
static inline void tox_list_remove(tox_list *lst)
{
lst->prev->next = lst->next;
lst->next->prev = lst->prev;
}
/****************************Array***************************
* Array which manages its own memory allocation.
* It stores copy of data (not pointers).
* TODO: Add wiki info usage.
************************************************************/
typedef struct tox_array {
uint8_t *data; /* last elem is data[len-1] */
uint32_t len;
size_t elem_size; /* in bytes */
} tox_array;
static inline void tox_array_init(tox_array *arr, size_t elem_size)
{
arr->len = 0;
arr->elem_size = elem_size;
arr->data = NULL;
}
static inline void tox_array_delete(tox_array *arr)
{
free(arr->data);
arr->len = arr->elem_size = 0;
}
static inline uint8_t tox_array_push_ptr(tox_array *arr, uint8_t *item)
{
uint8_t *temp = realloc(arr->data, arr->elem_size * (arr->len + 1));
if (temp == NULL)
return 0;
arr->data = temp;
if (item != NULL)
memcpy(arr->data + arr->elem_size * arr->len, item, arr->elem_size);
arr->len++;
return 1;
}
#define tox_array_push(arr, item) tox_array_push_ptr(arr, (uint8_t*)(&(item)))
/* Deletes num items from array.
* Not same as pop in stacks, because to access elements you use data.
*/
static inline void tox_array_pop(tox_array *arr, uint32_t num)
{
if (num == 0)
return;
if (num > arr->len)
return;
if (arr->len == num) {
free(arr->data);
arr->data = NULL;
arr->len = 0;
return;
}
uint8_t *temp = realloc(arr->data, arr->elem_size * (arr->len - num));
if (temp == NULL)
return;
arr->len -= num;
arr->data = temp;
}
/* TODO: return ptr and do not take type */
#define tox_array_get(arr, i, type) (((type*)(arr)->data)[i])
#define tox_array_for_each(arr, type, tmp_name) \
type *tmp_name = &tox_array_get(arr, 0, type); uint32_t tmp_name ## _i = 0; \
for (; tmp_name ## _i < (arr)->len; tmp_name = &tox_array_get(arr, ++ tmp_name ## _i, type))
/****************************Algorithms***************************
* Macro/generic definitions for useful algorithms
*****************************************************************/
/* Creates a new quick_sort implementation for arrays of the specified type.
* For a type T (eg: int, char), creates a function named T_quick_sort.
*
* Quick Sort: Complexity O(nlogn)
* arr - the array to sort
* n - the sort index (should be called with n = length(arr))
* cmpfn - a function that compares two values of type type.
* Must return -1, 0, 1 for a < b, a == b, and a > b respectively.
*/
/* Must be called in the header file. */
#define declare_quick_sort(type) \
void type##_quick_sort(type *arr, int n, int (*cmpfn)(type, type));
/* Must be called in the C file. */
#define make_quick_sort(type) \
void type##_quick_sort(type *arr, int n, int (*cmpfn)(type, type)) \
{ \
if ((n) < 2) \
return; \
type _p_ = (arr)[(n) / 2]; \
type *_l_ = (arr); \
type *_r_ = (arr) + n - 1; \
while (_l_ <= _r_) { \
if (cmpfn(*_l_, _p_) == -1) { \
++_l_; \
continue; \
} \
if (cmpfn(*_r_, _p_) == 1) { \
--_r_; \
continue; \
} \
type _t_ = *_l_; \
*_l_++ = *_r_; \
*_r_-- = _t_; \
} \
type##_quick_sort((arr), _r_ - (arr) + 1, cmpfn); \
type##_quick_sort(_l_, (arr) + n - _l_, cmpfn); \
}
#endif // MISC_TOOLS_H