1 /* ScummVM Tools
2  *
3  * ScummVM Tools is the legal property of its developers, whose
4  * names are too numerous to list here. Please refer to the
5  * COPYRIGHT file distributed with this source distribution.
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; either version 2
10  * of the License, or (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20  */
21 
22 #ifndef UTIL_H
23 #define UTIL_H
24 
25 #include "common/scummsys.h"
26 
27 /* An excercise in bloated macro writing ;-)*/
28 
29 /*Declare a flexarray type*/
30 #define FLEXARRAY(type, extra) struct{\
31 	type* data;\
32 	int used, size, itemsize;\
33 	extra\
34 }
35 
36 /* [DJ] Declare a flexarray type without extra fields - Visual C++ complains
37 ** when the FLEXARRAY macro is used and extra parameter is not specified
38 */
39 #define FLEXARRAY_NOEXTRA(type) struct{\
40 	type* data;\
41 	int used, size, itemsize;\
42 }
43 
44 /*Initialize a flexarray*/
45 #define FLEXARRAY_INIT(type, array) do {(array).itemsize=sizeof(type); (array).size=0; (array).used=0;} while(0)
46 
47 /*Prints an error message and returns (from the function using the macro)*/
48 #define FLEXARRAY_PANIC(message, errorcode) do{\
49 	fprintf message;\
50 	errorcode;\
51 } while(0)
52 
53 /*Use if the state of the array is incnsistent*/
54 #define FLEXARRAY_PANIC_BADSTATE(array, errorcode) FLEXARRAY_PANIC((stderr, "PANIC: flexarray "#array" is in an inconsistent state (%d,%d).\n", (array).used, (array).size), errorcode)
55 
56 /*Use if memory allocation fails*/
57 #define FLEXARRAY_PANIC_MEMORY(array, bytes, errorcode) FLEXARRAY_PANIC((stderr, "PANIC: Unable to allocate %d bytes for flexarray"#array"\n", bytes), errorcode)
58 
59 /*Allocates an initial array*/
60 #define FLEXARRAY_ALLOCATE_INITIAL(type, array, errorcode) do{\
61 	(array).data= (type*)sci_malloc(4*(array).itemsize);\
62 	if((array).data==0) FLEXARRAY_PANIC_MEMORY(array, 4*(array).itemsize, errorcode);\
63 	(array).size=4;\
64 	(array).used=0;\
65 } while(0)
66 
67 /*Doubles the size of the allocated area*/
68 #define FLEXARRAY_RESIZE(type, array, errorcode) do{\
69 	int size=(array).size*2*(array).itemsize;\
70 	(array).data= (type*)sci_realloc((array).data, size);\
71 	if((array).data==0) FLEXARRAY_PANIC_MEMORY(array, size, errorcode);\
72 	(array).size*=2;\
73 } while(0)
74 
75 /*Appends /value/ at the end of the array, resizing as necessary*/
76 #define FLEXARRAY_APPEND(type, array, value, errorcode) do\
77 {\
78 	if((array).used>=(array).size)\
79 	{\
80 		if((array).size==0) FLEXARRAY_ALLOCATE_INITIAL(type, array, errorcode);\
81 		else {\
82 			if((array).used==(array).size) FLEXARRAY_RESIZE(type, array, errorcode);\
83 			else FLEXARRAY_PANIC_BADSTATE(array, errorcode);\
84 		}\
85 	}\
86 	(array).data[(array).used++]=(value);\
87 }while(0)
88 
89 /*Adds space for a value at the end of the array, resizing as necessary, but
90  *does not initialize the value*/
91 #define FLEXARRAY_ADD_SPACE(type, array, items, errorcode) do{\
92 	if((array).used+items>(array).size)\
93 	{\
94 		if((array).size==0) FLEXARRAY_ALLOCATE_INITIAL(type, array, errorcode);\
95 		else if((array).used==(array).size) FLEXARRAY_RESIZE(type, array, errorcode);\
96 		else FLEXARRAY_PANIC_BADSTATE(array, errorcode);\
97 	}\
98 	(array).used++;\
99 } while(0)
100 
101 #endif
102