SDL 2.0
SDL_test_crc32.c File Reference
#include "SDL_config.h"
#include "SDL_test.h"
+ Include dependency graph for SDL_test_crc32.c:

Go to the source code of this file.

Functions

int SDLTest_Crc32Init (SDLTest_Crc32Context *crcContext)
 Initialize the CRC context. More...
 
int SDLTest_Crc32Calc (SDLTest_Crc32Context *crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32)
 calculate a crc32 from a data block More...
 
int SDLTest_Crc32CalcStart (SDLTest_Crc32Context *crcContext, CrcUint32 *crc32)
 
int SDLTest_Crc32CalcEnd (SDLTest_Crc32Context *crcContext, CrcUint32 *crc32)
 
int SDLTest_Crc32CalcBuffer (SDLTest_Crc32Context *crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32)
 
int SDLTest_Crc32Done (SDLTest_Crc32Context *crcContext)
 clean up CRC context More...
 

Function Documentation

◆ SDLTest_Crc32Calc()

int SDLTest_Crc32Calc ( SDLTest_Crc32Context crcContext,
CrcUint8 inBuf,
CrcUint32  inLen,
CrcUint32 crc32 
)

calculate a crc32 from a data block

Parameters
crcContextpointer to context variable
inBufinput buffer to checksum
inLenlength of input buffer
crc32pointer to Uint32 to store the final CRC into
Returns
0 for OK, -1 on error

Definition at line 72 of file SDL_test_crc32.c.

73{
74 if (SDLTest_Crc32CalcStart(crcContext,crc32)) {
75 return -1;
76 }
77
78 if (SDLTest_Crc32CalcBuffer(crcContext, inBuf, inLen, crc32)) {
79 return -1;
80 }
81
82 if (SDLTest_Crc32CalcEnd(crcContext, crc32)) {
83 return -1;
84 }
85
86 return 0;
87}
int SDLTest_Crc32CalcBuffer(SDLTest_Crc32Context *crcContext, CrcUint8 *inBuf, CrcUint32 inLen, CrcUint32 *crc32)
int SDLTest_Crc32CalcStart(SDLTest_Crc32Context *crcContext, CrcUint32 *crc32)
int SDLTest_Crc32CalcEnd(SDLTest_Crc32Context *crcContext, CrcUint32 *crc32)

References SDLTest_Crc32CalcBuffer(), SDLTest_Crc32CalcEnd(), and SDLTest_Crc32CalcStart().

Referenced by get_allocation_bucket().

◆ SDLTest_Crc32CalcBuffer()

int SDLTest_Crc32CalcBuffer ( SDLTest_Crc32Context crcContext,
CrcUint8 inBuf,
CrcUint32  inLen,
CrcUint32 crc32 
)

Definition at line 127 of file SDL_test_crc32.c.

128{
129 CrcUint8 *p;
130 register CrcUint32 crc;
131
132 if (crcContext==NULL) {
133 *crc32=0;
134 return -1;
135 }
136
137 if (inBuf==NULL) {
138 return -1;
139 }
140
141 /*
142 * Calculate CRC from data
143 */
144 crc = *crc32;
145 for (p = inBuf; inLen > 0; ++p, --inLen) {
146#ifdef ORIGINAL_METHOD
147 crc = (crc << 8) ^ crcContext->crc32_table[(crc >> 24) ^ *p];
148#else
149 crc = ((crc >> 8) & 0x00FFFFFF) ^ crcContext->crc32_table[ (crc ^ *p) & 0xFF ];
150#endif
151 }
152 *crc32 = crc;
153
154 return 0;
155}
GLfloat GLfloat p
#define CrcUint8
#define CrcUint32
#define NULL
Definition: begin_code.h:167
CrcUint32 crc32_table[256]

References SDLTest_Crc32Context::crc32_table, CrcUint32, CrcUint8, and NULL.

Referenced by SDLTest_Crc32Calc().

◆ SDLTest_Crc32CalcEnd()

int SDLTest_Crc32CalcEnd ( SDLTest_Crc32Context crcContext,
CrcUint32 crc32 
)

Definition at line 109 of file SDL_test_crc32.c.

110{
111 /* Sanity check pointers */
112 if (crcContext==NULL) {
113 *crc32=0;
114 return -1;
115 }
116
117 /*
118 * Return complement, per CRC-32 spec
119 */
120 *crc32 = (~(*crc32));
121
122 return 0;
123}

References NULL.

Referenced by SDLTest_Crc32Calc().

◆ SDLTest_Crc32CalcStart()

int SDLTest_Crc32CalcStart ( SDLTest_Crc32Context crcContext,
CrcUint32 crc32 
)

Definition at line 91 of file SDL_test_crc32.c.

92{
93 /* Sanity check pointers */
94 if (crcContext==NULL) {
95 *crc32=0;
96 return -1;
97 }
98
99 /*
100 * Preload shift register, per CRC-32 spec
101 */
102 *crc32 = 0xffffffff;
103
104 return 0;
105}

References NULL.

Referenced by SDLTest_Crc32Calc().

◆ SDLTest_Crc32Done()

int SDLTest_Crc32Done ( SDLTest_Crc32Context crcContext)

clean up CRC context

Parameters
crcContextpointer to context variable
Returns
0 for OK, -1 on error

Definition at line 157 of file SDL_test_crc32.c.

158{
159 if (crcContext==NULL) {
160 return -1;
161 }
162
163 return 0;
164}

References NULL.

◆ SDLTest_Crc32Init()

int SDLTest_Crc32Init ( SDLTest_Crc32Context crcContext)

Initialize the CRC context.

Note: The function initializes the crc table required for all crc calculations.

Parameters
crcContextpointer to context variable
Returns
0 for OK, -1 on error

Definition at line 34 of file SDL_test_crc32.c.

35{
36 int i,j;
38
39 /* Sanity check context pointer */
40 if (crcContext==NULL) {
41 return -1;
42 }
43
44 /*
45 * Build auxiliary table for parallel byte-at-a-time CRC-32
46 */
47#ifdef ORIGINAL_METHOD
48 for (i = 0; i < 256; ++i) {
49 for (c = i << 24, j = 8; j > 0; --j) {
50 c = c & 0x80000000 ? (c << 1) ^ CRC32_POLY : (c << 1);
51 }
52 crcContext->crc32_table[i] = c;
53 }
54#else
55 for (i=0; i<256; i++) {
56 c = i;
57 for (j=8; j>0; j--) {
58 if (c & 1) {
59 c = (c >> 1) ^ CRC32_POLY;
60 } else {
61 c >>= 1;
62 }
63 }
64 crcContext->crc32_table[i] = c;
65 }
66#endif
67
68 return 0;
69}
const GLubyte * c
#define CRC32_POLY
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int int in j)
Definition: SDL_x11sym.h:50
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:50

References CRC32_POLY, SDLTest_Crc32Context::crc32_table, CrcUint32, i, j, and NULL.

Referenced by SDLTest_TrackAllocations().