str.c

00001 /**
00002  * @file str.c
00003  * @brief String manipulation helper functions
00004  *
00005  * @section License
00006  *
00007  * Copyright (C) 2010-2017 Oryx Embedded SARL. All rights reserved.
00008  *
00009  * This program is free software; you can redistribute it and/or
00010  * modify it under the terms of the GNU General Public License
00011  * as published by the Free Software Foundation; either version 2
00012  * of the License, or (at your option) any later version.
00013  *
00014  * This program is distributed in the hope that it will be useful,
00015  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00016  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00017  * GNU General Public License for more details.
00018  *
00019  * You should have received a copy of the GNU General Public License
00020  * along with this program; if not, write to the Free Software Foundation,
00021  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
00022  *
00023  * @author Oryx Embedded SARL (www.oryx-embedded.com)
00024  * @version 1.7.6
00025  **/
00026 
00027 //Dependencies
00028 #include <stdio.h>
00029 #include <string.h>
00030 #include <ctype.h>
00031 #include "str.h"
00032 
00033 
00034 /**
00035  * @brief Duplicate a string
00036  * @param[in] s Pointer to a constant NULL-terminated character string
00037  * @return Address of the string that was copied, or NULL if the string cannot be copied
00038  **/
00039 
00040 char_t *strDuplicate(const char_t *s)
00041 {
00042    uint_t n;
00043    char_t *p;
00044 
00045    //Calculate the length occupied by the input string
00046    n = strlen(s) + 1;
00047 
00048    //Allocate memory to hold the new string
00049    p = osAllocMem(n);
00050    //Failed to allocate memory?
00051    if(!p)
00052       return NULL;
00053 
00054    //Make a copy of the input string
00055    memcpy(p, s, n);
00056 
00057    //Return a pointer to the newly created string
00058    return p;
00059 }
00060 
00061 
00062 /**
00063  * @brief Removes all leading and trailing whitespace from a string
00064  * @param[in] s The string that will be trimmed
00065  * @return String with whitespace stripped from the beginning and end
00066  **/
00067 
00068 char_t *strTrimWhitespace(char_t *s)
00069 {
00070    char_t *end;
00071    char_t *result;
00072 
00073    //Trim whitespace from the beginning
00074    while(isspace((uint8_t) *s)) s++;
00075    //Save the current position
00076    result = s;
00077 
00078    //Search for the first whitespace to remove
00079    //at the end of the string
00080    for(end = NULL; *s != '\0'; s++)
00081    {
00082       if(!isspace((uint8_t) *s))
00083          end = NULL;
00084       else if(!end)
00085          end = s;
00086    }
00087 
00088    //Trim whitespace from the end
00089    if(end) *end = '\0';
00090 
00091    //Return the string with leading and
00092    //trailing whitespace omitted
00093    return result;
00094 }
00095 
00096 
00097 /**
00098  * @brief Removes all trailing whitespace from a string
00099  * @param[in,out] s Pointer to a NULL-terminated character string
00100  **/
00101 
00102 void strRemoveTrailingSpace(char_t *s)
00103 {
00104    char_t *end;
00105 
00106    //Search for the first whitespace to remove
00107    //at the end of the string
00108    for(end = NULL; *s != '\0'; s++)
00109    {
00110       if(!isspace((uint8_t) *s))
00111          end = NULL;
00112       else if(!end)
00113          end = s;
00114    }
00115 
00116    //Trim whitespace from the end
00117    if(end) *end = '\0';
00118 }
00119 
00120 
00121 /**
00122  * @brief Replace all occurrences of the specified character
00123  * @param[in,out] s Pointer to a NULL-terminated character string
00124  * @param[in] oldChar The character to be replaced
00125  * @param[in] newChar The character that will replace all occurrences of oldChar
00126  **/
00127 
00128 void strReplaceChar(char_t *s, char_t oldChar, char_t newChar)
00129 {
00130    //Parse the specified string
00131    while(*s != '\0')
00132    {
00133       //Remplace all occurrences of the specified character
00134       if(*s == oldChar)
00135          *s = newChar;
00136    }
00137 }
00138 
00139 
00140 /**
00141  * @brief Copy string
00142  * @param[out] dest Pointer to the destination string
00143  * @param[in] src Pointer to the source string
00144  * @param[in] destSize Size of the buffer allocated for the destination string
00145  * @return Error code
00146  **/
00147 
00148 error_t strSafeCopy(char_t *dest, const char_t *src, size_t destSize)
00149 {
00150    size_t n;
00151 
00152    //Check parameters
00153    if(dest == NULL || src == NULL || destSize < 1)
00154       return ERROR_INVALID_PARAMETER;
00155 
00156    //Get the length of the source name
00157    n = strlen(src);
00158    //Limit the number of characters to be copied
00159    n = MIN(n, destSize - 1);
00160 
00161    //Copy the string
00162    strncpy(dest, src, n);
00163    //Properly terminate the string with a NULL character
00164    dest[n] = '\0';
00165 
00166    //Successful processing
00167    return NO_ERROR;
00168 }
00169