Microchip%20TCP_IP%20stack/TCPIP%20Stack/Helpers.c

/*********************************************************************
*
*                  Helper Functions for Microchip TCP/IP Stack
*
*********************************************************************
* FileName:                     Helpers.C
* Dependencies:         Compiler.h
*                                       Helpers.h
* Processor:            PIC18, PIC24F, PIC24H, dsPIC30F, dsPIC33F
* Complier:                     Microchip C18 v3.02 or higher
*                                       Microchip C30 v2.01 or higher
* Company:                      Microchip Technology, Inc.
*
 * Software License Agreement
 *
 * Copyright © 2002-2007 Microchip Technology Inc.  All rights 
 * reserved.
 *
 * Microchip licenses to you the right to use, modify, copy, and 
 * distribute: 
 * (i)  the Software when embedded on a Microchip microcontroller or 
 *      digital signal controller product (“Device”) which is 
 *      integrated into Licensee’s product; or
 * (ii) ONLY the Software driver source files ENC28J60.c and 
 *      ENC28J60.h ported to a non-Microchip device used in 
 *      conjunction with a Microchip ethernet controller for the 
 *      sole purpose of interfacing with the ethernet controller. 
 *
 * You should refer to the license agreement accompanying this 
 * Software for additional information regarding your rights and 
 * obligations.
 *
 * THE SOFTWARE AND DOCUMENTATION ARE PROVIDED “AS IS” WITHOUT 
 * WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT 
 * LIMITATION, ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A 
 * PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT SHALL 
 * MICROCHIP BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT OR 
 * CONSEQUENTIAL DAMAGES, LOST PROFITS OR LOST DATA, COST OF 
 * PROCUREMENT OF SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES, ANY CLAIMS 
 * BY THIRD PARTIES (INCLUDING BUT NOT LIMITED TO ANY DEFENSE 
 * THEREOF), ANY CLAIMS FOR INDEMNITY OR CONTRIBUTION, OR OTHER 
 * SIMILAR COSTS, WHETHER ASSERTED ON THE BASIS OF CONTRACT, TORT 
 * (INCLUDING NEGLIGENCE), BREACH OF WARRANTY, OR OTHERWISE.
*
*
* Author               Date    Comment
*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
* Nilesh Rajbharti     5/17/01 Original        (Rev 1.0)
* Nilesh Rajbharti     2/9/02  Cleanup
* Nilesh Rajbharti     6/25/02 Rewritten CalcIPChecksum() to avoid
*                              multi-byte shift operation.
* Howard Schlunder              2/9/05 Added hexatob(), btohexa_high(), and
*                                                          btohexa_low()
* Howard Schlunder    10/10/06 Optimized swapl()
********************************************************************/
#define __HELPERS_C

#include "TCPIP Stack/TCPIP.h"


#if defined(STACK_USE_HTTP_SERVER)
/*********************************************************************
* Function:             void UnencodeURL(BYTE *URL)
*
* PreCondition: None
*
* Input:                *URL: Pointer to a null terminated URL string
*
* Output:               All escape sequences (ex: %20) are converted to 
*                               liternal representations in the URL string.
*
* Side Effects: None
*
* Overview:             None
*
* Note:                 None
********************************************************************/
void UnencodeURL(BYTE *URL)
{
        BYTE *Right, *Copy;
        WORD_VAL Number;

        while(Right = (BYTE*)strchr((char*)URL, '%'))
        {
                // Make sure the string is long enough
                if(Right[1] == '\0')
                        break;
                if(Right[2] == '\0')
                        break;

                // Update the string in place
                Number.v[0] = Right[2];
                Number.v[1] = Right[1];
                *Right++ = hexatob(Number);
                URL = Right;

                // Remove two blank spots by shifting all remaining characters right two
                Copy = Right + 2;
                while(*Right++ = *Copy++);
        }
}                   
#endif


/*********************************************************************
* Function:             BOOL StringToIPAddress(BYTE *str, IP_ADDR *IPAddress)
*
* PreCondition: None
*
* Input:                str: Pointer to a null terminated URL, hostname, or dotted decimal IP address string
*                               IPAddress: Pointer to a location to write the decoded IP address.  Result is big endian.
*
* Output:               TRUE if a IP address was successfully decoded
*                               FALSE if no IP address could be found or wrong format
*
* Side Effects: None
*
* Overview:             None
*
* Note:                 None
********************************************************************/
BOOL StringToIPAddress(BYTE *str, IP_ADDR *IPAddress)
{
    BYTE i, j, k;
        BYTE buffer[4];

        j = 0;
        k = 0;

    while(i = *str++)
    {
        if(i == '.')
        {
            buffer[j] = '\0';
                        j = 0;
            IPAddress->v[k++] = atoi((char*)buffer);
        }
        else if(i < '0' || i > '9')
                {
            return FALSE;
                }
                else
                {
                        buffer[j++] = i;
                        if(k >= sizeof(IP_ADDR))
                                return FALSE;
                }

                if(j >= sizeof(buffer))
                        return FALSE;
    }

        buffer[j] = '\0';
    IPAddress->v[k] = atoi((char*)buffer);
    return (k == 3u);
}


//#if defined(__C30__) || defined(HI_TECH_C)
/*********************************************************************
* Function:             void uitoa(WORD Value, BYTE *Buffer)
*
* PreCondition: None
*
* Input:                Value: Unsigned integer to be converted
*                               Buffer: Pointer to a location to write the string
*
* Output:               *Buffer: Receives the resulting string
*
* Side Effects: None
*
* Overview:             The function converts an unsigned integer (16 bits) 
*                               into a null terminated decimal string.
*
* Note:                 None
********************************************************************/
void uitoa(WORD Value, BYTE *Buffer)
{
        BYTE i;
        WORD Digit;
        WORD Divisor;
        BOOL Printed = FALSE;

        if(Value)
        {
                for(i = 0, Divisor = 10000; i < 5; i++)
                {
                        Digit = Value/Divisor;
                        if(Digit || Printed)
                        {
                                *Buffer++ = '0' + Digit;
                                Value -= Digit*Divisor;
                                Printed = TRUE;
                        }
                        Divisor /= 10;
                }
        }
        else
        {
                *Buffer++ = '0';
        }

        *Buffer = '\0';
}                           
//#endif


/*********************************************************************
* Function:        BYTE hexatob(WORD_VAL AsciiChars)
*
* PreCondition:    None
*
* Input:           Two ascii bytes; each ranged '0'-'9', 'A'-'F', or
*                                               'a'-'f'
*
* Output:          The resulting packed byte: 0x00-0xFF
*
* Side Effects:    None
*
* Overview:        None
*
* Note:                 None
********************************************************************/
BYTE hexatob(WORD_VAL AsciiChars)
{
        // Convert lowercase to uppercase
        if(AsciiChars.v[1] > 'F')
                AsciiChars.v[1] -= 'a'-'A';
        if(AsciiChars.v[0] > 'F')
                AsciiChars.v[0] -= 'a'-'A';

        // Convert 0-9, A-F to 0x0-0xF
        if(AsciiChars.v[1] > '9')
                AsciiChars.v[1] -= 'A' - 10;
        else
                AsciiChars.v[1] -= '0';

        if(AsciiChars.v[0] > '9')
                AsciiChars.v[0] -= 'A' - 10;
        else
                AsciiChars.v[0] -= '0';

        // Concatenate
        return (AsciiChars.v[1]<<4) |  AsciiChars.v[0];
}

/*********************************************************************
* Function:        BYTE btohexa_high(BYTE b)
*
* PreCondition:    None
*
* Input:           One byte ranged 0x00-0xFF
*
* Output:          An ascii byte (always uppercase) between '0'-'9' 
*                                       or 'A'-'F' that corresponds to the upper 4 bits of
*                                       the input byte.
*                                       ex: b = 0xAE, btohexa_high() returns 'A'
*
* Side Effects:    None
*
* Overview:        None
*
* Note:                 None
********************************************************************/
BYTE btohexa_high(BYTE b)
{
        b >>= 4;
        return (b>0x9u) ? b+'A'-10:b+'0';
}

/*********************************************************************
* Function:        BYTE btohexa_low(BYTE b)
*
* PreCondition:    None
*
* Input:           One byte ranged 0x00-0xFF
*
* Output:          An ascii byte (always uppercase) between '0'-'9' 
*                                       or 'A'-'F' that corresponds to the lower 4 bits of
*                                       the input byte.
*                                       ex: b = 0xAE, btohexa_low() returns 'E'
*
* Side Effects:    None
*
* Overview:        None
*
* Note:                 None
********************************************************************/
BYTE btohexa_low(BYTE b)
{
        b &= 0x0F;
        return (b>9u) ? b+'A'-10:b+'0';
}


WORD swaps(WORD v)
{
        WORD_VAL t;
        BYTE b;

        t.Val   = v;
        b       = t.v[1];
        t.v[1]  = t.v[0];
        t.v[0]  = b;

        return t.Val;
}


DWORD swapl(DWORD v)
{
        // Swap bytes 0 and 3
        ((DWORD_VAL*)&v)->v[0] ^= ((DWORD_VAL*)&v)->v[3];
        ((DWORD_VAL*)&v)->v[3] ^= ((DWORD_VAL*)&v)->v[0];
        ((DWORD_VAL*)&v)->v[0] ^= ((DWORD_VAL*)&v)->v[3];

        // Swap bytes 1 and 2
        ((DWORD_VAL*)&v)->v[1] ^= ((DWORD_VAL*)&v)->v[2];
        ((DWORD_VAL*)&v)->v[2] ^= ((DWORD_VAL*)&v)->v[1];
        ((DWORD_VAL*)&v)->v[1] ^= ((DWORD_VAL*)&v)->v[2];

        return v;
}


WORD CalcIPChecksum(BYTE* buffer, WORD count)
{
        WORD i;
        WORD *val;
        DWORD_VAL sum = {0x00000000ul};

        i = count >> 1;
        val = (WORD*)buffer;

        // Calculate the sum of all words
        while(i--)
                sum.Val += (DWORD)*val++;

        // Add in the sum of the remaining byte, if present
        if(((WORD_VAL*)&count)->bits.b0)
                sum.Val += (DWORD)*(BYTE*)val;

        // Do an end-around carry (one's complement arrithmatic)
        sum.Val = (DWORD)sum.w[0] + (DWORD)sum.w[1];

        // Do another end-around carry in case if the prior add 
        // caused a carry out
        sum.w[0] += sum.w[1];

        // Return the resulting checksum
        return ~sum.w[0];
}


/*********************************************************************
* Function:        WORD CalcIPBufferChecksum(WORD len)
*
* PreCondition:    TCPInit() is already called     AND
*                  MAC buffer pointer set to starting of buffer
*
* Input:           len     - Total number of bytes to calculate
*                          checksum for.
*
* Output:          16-bit checksum as defined by rfc 793.
*
* Side Effects:    None
*
* Overview:        This function performs checksum calculation in
*                  MAC buffer itself.
*
* Note:            None
********************************************************************/
#if defined(NON_MCHP_MAC)
WORD CalcIPBufferChecksum(WORD len)
{
        DWORD_VAL Checksum = {0x00000000ul};
        WORD ChunkLen;
        BYTE DataBuffer[20];    // Must be an even size
        WORD *DataPtr;

        while(len)
        {
                // Obtain a chunk of data (less SPI overhead compared 
                // to requesting one byte at a time)
                ChunkLen = len > sizeof(DataBuffer) ? sizeof(DataBuffer) : len;
                MACGetArray(DataBuffer, ChunkLen);
                len -= ChunkLen;

                // Take care of a last odd numbered data byte
                if(((WORD_VAL*)&ChunkLen)->bits.b0)
                {
                        DataBuffer[ChunkLen] = 0x00;
                        ChunkLen++;
                }

                // Calculate the checksum over this chunk
                DataPtr = (WORD*)&DataBuffer[0];
                while(ChunkLen)
                {
                        Checksum.Val += *DataPtr++;
                        ChunkLen -= 2;
                }
        }
        
        // Do an end-around carry (one's complement arrithmatic)
        Checksum.Val = (DWORD)Checksum.w[0] + (DWORD)Checksum.w[1];

        // Do another end-around carry in case if the prior add 
        // caused a carry out
        Checksum.w[0] += Checksum.w[1];

        // Return the resulting checksum
        return ~Checksum.w[0];
}
#endif

/*********************************************************************
* Function:             char *strupr(char *s)
*
* PreCondition: None
*
* Input:                s: Pointer to a null terminated string to convert.
*
* Output:               char* return: Pointer to the initial string
*                               *s: String is updated in to have all upper case 
*                                       characters
*
* Side Effects: None
*
* Overview:             The function sequentially converts all lower case 
*                               characters in the input s string to upper case 
*                               characters.  Non a-z characters are skipped.
*
* Note:                 None
********************************************************************/
#if defined(__C30__) || defined(HI_TECH_C)
char *strupr(char *s)
{
        char c;
        char *t;

        t = s;
        while( (c = *t) )
        {
                if(c >= 'a' && c <= 'z')
                {
                        *t -= ('a' - 'A');
                }
                t++;
        }
        return s;
}
#endif
1	/*********************************************************************
2	*
3	* Helper Functions for Microchip TCP/IP Stack
4	*
5	*********************************************************************
6	* FileName: Helpers.C
7	* Dependencies: Compiler.h
8	* Helpers.h
9	* Processor: PIC18, PIC24F, PIC24H, dsPIC30F, dsPIC33F
10	* Complier: Microchip C18 v3.02 or higher
11	* Microchip C30 v2.01 or higher
12	* Company: Microchip Technology, Inc.
13	*
14	* Software License Agreement
15	*
16	* Copyright © 2002-2007 Microchip Technology Inc. All rights
17	* reserved.
18	*
19	* Microchip licenses to you the right to use, modify, copy, and
20	* distribute:
21	* (i) the Software when embedded on a Microchip microcontroller or
22	* digital signal controller product (“Device”) which is
23	* integrated into Licensee’s product; or
24	* (ii) ONLY the Software driver source files ENC28J60.c and
25	* ENC28J60.h ported to a non-Microchip device used in
26	* conjunction with a Microchip ethernet controller for the
27	* sole purpose of interfacing with the ethernet controller.
28	*
29	* You should refer to the license agreement accompanying this
30	* Software for additional information regarding your rights and
31	* obligations.
32	*
33	* THE SOFTWARE AND DOCUMENTATION ARE PROVIDED “AS IS” WITHOUT
34	* WARRANTY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT
35	* LIMITATION, ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A
36	* PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT SHALL
37	* MICROCHIP BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT OR
38	* CONSEQUENTIAL DAMAGES, LOST PROFITS OR LOST DATA, COST OF
39	* PROCUREMENT OF SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES, ANY CLAIMS
40	* BY THIRD PARTIES (INCLUDING BUT NOT LIMITED TO ANY DEFENSE
41	* THEREOF), ANY CLAIMS FOR INDEMNITY OR CONTRIBUTION, OR OTHER
42	* SIMILAR COSTS, WHETHER ASSERTED ON THE BASIS OF CONTRACT, TORT
43	* (INCLUDING NEGLIGENCE), BREACH OF WARRANTY, OR OTHERWISE.
44	*
45	*
46	* Author Date Comment
47	*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
48	* Nilesh Rajbharti 5/17/01 Original (Rev 1.0)
49	* Nilesh Rajbharti 2/9/02 Cleanup
50	* Nilesh Rajbharti 6/25/02 Rewritten CalcIPChecksum() to avoid
51	* multi-byte shift operation.
52	* Howard Schlunder 2/9/05 Added hexatob(), btohexa_high(), and
53	* btohexa_low()
54	* Howard Schlunder 10/10/06 Optimized swapl()
55	********************************************************************/
56	#define __HELPERS_C
57
58	#include "TCPIP Stack/TCPIP.h"
59
60
61	#if defined(STACK_USE_HTTP_SERVER)
62	/*********************************************************************
63	* Function: void UnencodeURL(BYTE *URL)
64	*
65	* PreCondition: None
66	*
67	* Input: *URL: Pointer to a null terminated URL string
68	*
69	* Output: All escape sequences (ex: %20) are converted to
70	* liternal representations in the URL string.
71	*
72	* Side Effects: None
73	*
74	* Overview: None
75	*
76	* Note: None
77	********************************************************************/
78	void UnencodeURL(BYTE *URL)
79	{
80	BYTE Right, Copy;
81	WORD_VAL Number;
82
83	while(Right = (BYTE)strchr((char)URL, '%'))
84	{
85	// Make sure the string is long enough
86	if(Right[1] == '\0')
87	break;
88	if(Right[2] == '\0')
89	break;
90
91	// Update the string in place
92	Number.v[0] = Right[2];
93	Number.v[1] = Right[1];
94	*Right++ = hexatob(Number);
95	URL = Right;
96
97	// Remove two blank spots by shifting all remaining characters right two
98	Copy = Right + 2;
99	while(Right++ = Copy++);
100	}
101	}
102	#endif
103
104
105	/*********************************************************************
106	* Function: BOOL StringToIPAddress(BYTE str, IP_ADDR IPAddress)
107	*
108	* PreCondition: None
109	*
110	* Input: str: Pointer to a null terminated URL, hostname, or dotted decimal IP address string
111	* IPAddress: Pointer to a location to write the decoded IP address. Result is big endian.
112	*
113	* Output: TRUE if a IP address was successfully decoded
114	* FALSE if no IP address could be found or wrong format
115	*
116	* Side Effects: None
117	*
118	* Overview: None
119	*
120	* Note: None
121	********************************************************************/
122	BOOL StringToIPAddress(BYTE str, IP_ADDR IPAddress)
123	{
124	BYTE i, j, k;
125	BYTE buffer[4];
126
127	j = 0;
128	k = 0;
129
130	while(i = *str++)
131	{
132	if(i == '.')
133	{
134	buffer[j] = '\0';
135	j = 0;
136	IPAddress->v[k++] = atoi((char*)buffer);
137	}
138	else if(i < '0' \|\| i > '9')
139	{
140	return FALSE;
141	}
142	else
143	{
144	buffer[j++] = i;
145	if(k >= sizeof(IP_ADDR))
146	return FALSE;
147	}
148
149	if(j >= sizeof(buffer))
150	return FALSE;
151	}
152
153	buffer[j] = '\0';
154	IPAddress->v[k] = atoi((char*)buffer);
155	return (k == 3u);
156	}
157
158
159	//#if defined(__C30__) \|\| defined(HI_TECH_C)
160	/*********************************************************************
161	* Function: void uitoa(WORD Value, BYTE *Buffer)
162	*
163	* PreCondition: None
164	*
165	* Input: Value: Unsigned integer to be converted
166	* Buffer: Pointer to a location to write the string
167	*
168	* Output: *Buffer: Receives the resulting string
169	*
170	* Side Effects: None
171	*
172	* Overview: The function converts an unsigned integer (16 bits)
173	* into a null terminated decimal string.
174	*
175	* Note: None
176	********************************************************************/
177	void uitoa(WORD Value, BYTE *Buffer)
178	{
179	BYTE i;
180	WORD Digit;
181	WORD Divisor;
182	BOOL Printed = FALSE;
183
184	if(Value)
185	{
186	for(i = 0, Divisor = 10000; i < 5; i++)
187	{
188	Digit = Value/Divisor;
189	if(Digit \|\| Printed)
190	{
191	*Buffer++ = '0' + Digit;
192	Value -= Digit*Divisor;
193	Printed = TRUE;
194	}
195	Divisor /= 10;
196	}
197	}
198	else
199	{
200	*Buffer++ = '0';
201	}
202
203	*Buffer = '\0';
204	}
205	//#endif
206
207
208	/*********************************************************************
209	* Function: BYTE hexatob(WORD_VAL AsciiChars)
210	*
211	* PreCondition: None
212	*
213	* Input: Two ascii bytes; each ranged '0'-'9', 'A'-'F', or
214	* 'a'-'f'
215	*
216	* Output: The resulting packed byte: 0x00-0xFF
217	*
218	* Side Effects: None
219	*
220	* Overview: None
221	*
222	* Note: None
223	********************************************************************/
224	BYTE hexatob(WORD_VAL AsciiChars)
225	{
226	// Convert lowercase to uppercase
227	if(AsciiChars.v[1] > 'F')
228	AsciiChars.v[1] -= 'a'-'A';
229	if(AsciiChars.v[0] > 'F')
230	AsciiChars.v[0] -= 'a'-'A';
231
232	// Convert 0-9, A-F to 0x0-0xF
233	if(AsciiChars.v[1] > '9')
234	AsciiChars.v[1] -= 'A' - 10;
235	else
236	AsciiChars.v[1] -= '0';
237
238	if(AsciiChars.v[0] > '9')
239	AsciiChars.v[0] -= 'A' - 10;
240	else
241	AsciiChars.v[0] -= '0';
242
243	// Concatenate
244	return (AsciiChars.v[1]<<4) \| AsciiChars.v[0];
245	}
246
247	/*********************************************************************
248	* Function: BYTE btohexa_high(BYTE b)
249	*
250	* PreCondition: None
251	*
252	* Input: One byte ranged 0x00-0xFF
253	*
254	* Output: An ascii byte (always uppercase) between '0'-'9'
255	* or 'A'-'F' that corresponds to the upper 4 bits of
256	* the input byte.
257	* ex: b = 0xAE, btohexa_high() returns 'A'
258	*
259	* Side Effects: None
260	*
261	* Overview: None
262	*
263	* Note: None
264	********************************************************************/
265	BYTE btohexa_high(BYTE b)
266	{
267	b >>= 4;
268	return (b>0x9u) ? b+'A'-10:b+'0';
269	}
270
271	/*********************************************************************
272	* Function: BYTE btohexa_low(BYTE b)
273	*
274	* PreCondition: None
275	*
276	* Input: One byte ranged 0x00-0xFF
277	*
278	* Output: An ascii byte (always uppercase) between '0'-'9'
279	* or 'A'-'F' that corresponds to the lower 4 bits of
280	* the input byte.
281	* ex: b = 0xAE, btohexa_low() returns 'E'
282	*
283	* Side Effects: None
284	*
285	* Overview: None
286	*
287	* Note: None
288	********************************************************************/
289	BYTE btohexa_low(BYTE b)
290	{
291	b &= 0x0F;
292	return (b>9u) ? b+'A'-10:b+'0';
293	}
294
295
296	WORD swaps(WORD v)
297	{
298	WORD_VAL t;
299	BYTE b;
300
301	t.Val = v;
302	b = t.v[1];
303	t.v[1] = t.v[0];
304	t.v[0] = b;
305
306	return t.Val;
307	}
308
309
310	DWORD swapl(DWORD v)
311	{
312	// Swap bytes 0 and 3
313	((DWORD_VAL)&v)->v[0] ^= ((DWORD_VAL)&v)->v[3];
314	((DWORD_VAL)&v)->v[3] ^= ((DWORD_VAL)&v)->v[0];
315	((DWORD_VAL)&v)->v[0] ^= ((DWORD_VAL)&v)->v[3];
316
317	// Swap bytes 1 and 2
318	((DWORD_VAL)&v)->v[1] ^= ((DWORD_VAL)&v)->v[2];
319	((DWORD_VAL)&v)->v[2] ^= ((DWORD_VAL)&v)->v[1];
320	((DWORD_VAL)&v)->v[1] ^= ((DWORD_VAL)&v)->v[2];
321
322	return v;
323	}
324
325
326	WORD CalcIPChecksum(BYTE* buffer, WORD count)
327	{
328	WORD i;
329	WORD *val;
330	DWORD_VAL sum = {0x00000000ul};
331
332	i = count >> 1;
333	val = (WORD*)buffer;
334
335	// Calculate the sum of all words
336	while(i--)
337	sum.Val += (DWORD)*val++;
338
339	// Add in the sum of the remaining byte, if present
340	if(((WORD_VAL*)&count)->bits.b0)
341	sum.Val += (DWORD)(BYTE)val;
342
343	// Do an end-around carry (one's complement arrithmatic)
344	sum.Val = (DWORD)sum.w[0] + (DWORD)sum.w[1];
345
346	// Do another end-around carry in case if the prior add
347	// caused a carry out
348	sum.w[0] += sum.w[1];
349
350	// Return the resulting checksum
351	return ~sum.w[0];
352	}
353
354
355	/*********************************************************************
356	* Function: WORD CalcIPBufferChecksum(WORD len)
357	*
358	* PreCondition: TCPInit() is already called AND
359	* MAC buffer pointer set to starting of buffer
360	*
361	* Input: len - Total number of bytes to calculate
362	* checksum for.
363	*
364	* Output: 16-bit checksum as defined by rfc 793.
365	*
366	* Side Effects: None
367	*
368	* Overview: This function performs checksum calculation in
369	* MAC buffer itself.
370	*
371	* Note: None
372	********************************************************************/
373	#if defined(NON_MCHP_MAC)
374	WORD CalcIPBufferChecksum(WORD len)
375	{
376	DWORD_VAL Checksum = {0x00000000ul};
377	WORD ChunkLen;
378	BYTE DataBuffer[20]; // Must be an even size
379	WORD *DataPtr;
380
381	while(len)
382	{
383	// Obtain a chunk of data (less SPI overhead compared
384	// to requesting one byte at a time)
385	ChunkLen = len > sizeof(DataBuffer) ? sizeof(DataBuffer) : len;
386	MACGetArray(DataBuffer, ChunkLen);
387	len -= ChunkLen;
388
389	// Take care of a last odd numbered data byte
390	if(((WORD_VAL*)&ChunkLen)->bits.b0)
391	{
392	DataBuffer[ChunkLen] = 0x00;
393	ChunkLen++;
394	}
395
396	// Calculate the checksum over this chunk
397	DataPtr = (WORD*)&DataBuffer[0];
398	while(ChunkLen)
399	{
400	Checksum.Val += *DataPtr++;
401	ChunkLen -= 2;
402	}
403	}
404
405	// Do an end-around carry (one's complement arrithmatic)
406	Checksum.Val = (DWORD)Checksum.w[0] + (DWORD)Checksum.w[1];
407
408	// Do another end-around carry in case if the prior add
409	// caused a carry out
410	Checksum.w[0] += Checksum.w[1];
411
412	// Return the resulting checksum
413	return ~Checksum.w[0];
414	}
415	#endif
416
417	/*********************************************************************
418	* Function: char strupr(char s)
419	*
420	* PreCondition: None
421	*
422	* Input: s: Pointer to a null terminated string to convert.
423	*
424	* Output: char* return: Pointer to the initial string
425	* *s: String is updated in to have all upper case
426	* characters
427	*
428	* Side Effects: None
429	*
430	* Overview: The function sequentially converts all lower case
431	* characters in the input s string to upper case
432	* characters. Non a-z characters are skipped.
433	*
434	* Note: None
435	********************************************************************/
436	#if defined(__C30__) \|\| defined(HI_TECH_C)
437	char strupr(char s)
438	{
439	char c;
440	char *t;
441
442	t = s;
443	while( (c = *t) )
444	{
445	if(c >= 'a' && c <= 'z')
446	{
447	*t -= ('a' - 'A');
448	}
449	t++;
450	}
451	return s;
452	}
453	#endif