From a6d24d323b402964086dbd816d54897b6d9e4d38 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Sat, 30 Jul 2011 19:31:17 +0200 Subject: at91lib: re-add utility/string.c from basic-dataflash-example --- at91lib/utility/string.c | 239 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 239 insertions(+) create mode 100644 at91lib/utility/string.c diff --git a/at91lib/utility/string.c b/at91lib/utility/string.c new file mode 100644 index 0000000..6c2af0d --- /dev/null +++ b/at91lib/utility/string.c @@ -0,0 +1,239 @@ +/* ---------------------------------------------------------------------------- + * ATMEL Microcontroller Software Support + * ---------------------------------------------------------------------------- + * Copyright (c) 2008, Atmel Corporation + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * - Redistributions of source code must retain the above copyright notice, + * this list of conditions and the disclaimer below. + * + * Atmel's name may not be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE + * DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, + * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, + * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * ---------------------------------------------------------------------------- + */ + +//------------------------------------------------------------------------------ +/// \unit +/// +/// !Purpose +/// +/// Implementation of several methods defined in string.h, for reducing the +/// memory footprint when using them (since the whole libc.o file gets included +/// even when using a single method). +/// +/// !Usage +/// +/// Add string.c to the list of files to compile for the project. This will +/// automatically replace standard libc methods by the custom ones. +//------------------------------------------------------------------------------ + +//------------------------------------------------------------------------------ +// Headers +//------------------------------------------------------------------------------ + +#include + +//------------------------------------------------------------------------------ +// Global Functions +//------------------------------------------------------------------------------ + +//------------------------------------------------------------------------------ +/// Copies data from a source buffer into a destination buffer. The two buffers +/// must NOT overlap. Returns the destination buffer. +/// \param pDestination Destination buffer. +/// \param pSource Source buffer. +/// \param num Number of bytes to copy. +//------------------------------------------------------------------------------ +void * memcpy(void *pDestination, const void *pSource, size_t num) +{ + unsigned char *pByteDestination; + unsigned char *pByteSource; + unsigned int *pAlignedSource = (unsigned int *) pSource; + unsigned int *pAlignedDestination = (unsigned int *) pDestination; + + // If num is more than 4 bytes, and both dest. and source are aligned, + // then copy dwords + if ((((unsigned int) pAlignedDestination & 0x3) == 0) + && (((unsigned int) pAlignedSource & 0x3) == 0) + && (num >= 4)) { + + while (num >= 4) { + + *pAlignedDestination++ = *pAlignedSource++; + num -= 4; + } + } + + // Copy remaining bytes + pByteDestination = (unsigned char *) pAlignedDestination; + pByteSource = (unsigned char *) pAlignedSource; + while (num--) { + + *pByteDestination++ = *pByteSource++; + } + + return pDestination; +} + +//------------------------------------------------------------------------------ +/// Fills a memory region with the given value. Returns a pointer to the +/// memory region. +/// \param pBuffer Pointer to the start of the memory region to fill +/// \param value Value to fill the region with +/// \param num Size to fill in bytes +//------------------------------------------------------------------------------ +void * memset(void *pBuffer, int value, size_t num) +{ + unsigned char *pByteDestination; + unsigned int *pAlignedDestination = (unsigned int *) pBuffer; + unsigned int alignedValue = (value << 24) | (value << 16) | (value << 8) | value; + + // Set words if possible + if ((((unsigned int) pAlignedDestination & 0x3) == 0) && (num >= 4)) { + while (num >= 4) { + *pAlignedDestination++ = alignedValue; + num -= 4; + } + } + // Set remaining bytes + pByteDestination = (unsigned char *) pAlignedDestination; + while (num--) { + *pByteDestination++ = value; + } + return pBuffer; +} + +//----------------------------------------------------------------------------- +/// Search a character in the given string. +/// Returns a pointer to the character location. +/// \param pString Pointer to the start of the string to search. +/// \param character The character to find. +//----------------------------------------------------------------------------- +char * strchr(const char *pString, int character) +{ + char * p = (char *)pString; + char c = character & 0xFF; + + while(*p != c) { + if (*p == 0) { + return 0; + } + p++; + } + return p; +} + +//----------------------------------------------------------------------------- +/// Return the length of a given string +/// \param pString Pointer to the start of the string. +//----------------------------------------------------------------------------- +size_t strlen(const char *pString) +{ + unsigned int length = 0; + + while(*pString++ != 0) { + length++; + } + return length; +} + + +//----------------------------------------------------------------------------- +/// Search a character backword from the end of given string. +/// Returns a pointer to the character location. +/// \param pString Pointer to the start of the string to search. +/// \param character The character to find. +//----------------------------------------------------------------------------- +char * strrchr(const char *pString, int character) +{ + char *p = 0; + + while(*pString != 0) { + if (*pString++ == character) { + p = (char*)pString; + } + } + return p; +} + +//----------------------------------------------------------------------------- +/// Copy from source string to destination string +/// Return a pointer to the destination string +/// \param pDestination Pointer to the destination string. +/// \param pSource Pointer to the source string. +//----------------------------------------------------------------------------- +char * strcpy(char *pDestination, const char *pSource) +{ + char *pSaveDest = pDestination; + + for(; (*pDestination = *pSource) != 0; ++pSource, ++pDestination); + return pSaveDest; +} + +//----------------------------------------------------------------------------- +/// Compare the first specified bytes of 2 given strings +/// Return 0 if equals +/// Return >0 if 1st string > 2nd string +/// Return <0 if 1st string < 2nd string +/// \param pString1 Pointer to the start of the 1st string. +/// \param pString2 Pointer to the start of the 2nd string. +/// \param count Number of bytes that should be compared. +//----------------------------------------------------------------------------- +int strncmp(const char *pString1, const char *pString2, size_t count) +{ + int r; + + while(count) { + r = *pString1 - *pString2; + if (r == 0) { + if (*pString1 == 0) { + break; + } + pString1++; + pString2++; + count--; + continue; + } + return r; + } + return 0; +} + +//----------------------------------------------------------------------------- +/// Copy the first number of bytes from source string to destination string +/// Return the pointer to the destination string. +/// \param pDestination Pointer to the start of destination string. +/// \param pSource Pointer to the start of the source string. +/// \param count Number of bytes that should be copied. +//----------------------------------------------------------------------------- +char * strncpy(char *pDestination, const char *pSource, size_t count) +{ + char *pSaveDest = pDestination; + + while (count) { + *pDestination = *pSource; + if (*pSource == 0) { + break; + } + pDestination++; + pSource++; + count--; + } + return pSaveDest; +} + -- cgit v1.2.3