Cores:WString.cpp
出自YFRobotwiki
WString.cpp
/*
WString.cpp - String library for Wiring & Arduino
...mostly rewritten by Paul Stoffregen...
Copyright (c) 2009-10 Hernando Barragan. All rights reserved.
Copyright 2011, Paul Stoffregen, paul@pjrc.com
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "WString.h"
/*********************************************/
/* Constructors */
/*********************************************/
String::String(const char *cstr)
{
init();
if (cstr) copy(cstr, strlen(cstr));
}
String::String(const String &value)
{
init();
*this = value;
}
String::String(const __FlashStringHelper *pstr)
{
init();
*this = pstr;
}
#ifdef __GXX_EXPERIMENTAL_CXX0X__
String::String(String &&rval)
{
init();
move(rval);
}
String::String(StringSumHelper &&rval)
{
init();
move(rval);
}
#endif
String::String(char c)
{
init();
char buf[2];
buf[0] = c;
buf[1] = 0;
*this = buf;
}
String::String(unsigned char value, unsigned char base)
{
init();
char buf[1 + 8 * sizeof(unsigned char)];
utoa(value, buf, base);
*this = buf;
}
String::String(int value, unsigned char base)
{
init();
char buf[2 + 8 * sizeof(int)];
itoa(value, buf, base);
*this = buf;
}
String::String(unsigned int value, unsigned char base)
{
init();
char buf[1 + 8 * sizeof(unsigned int)];
utoa(value, buf, base);
*this = buf;
}
String::String(long value, unsigned char base)
{
init();
char buf[2 + 8 * sizeof(long)];
ltoa(value, buf, base);
*this = buf;
}
String::String(unsigned long value, unsigned char base)
{
init();
char buf[1 + 8 * sizeof(unsigned long)];
ultoa(value, buf, base);
*this = buf;
}
String::String(float value, unsigned char decimalPlaces)
{
init();
char buf[33];
*this = dtostrf(value, (decimalPlaces + 2), decimalPlaces, buf);
}
String::String(double value, unsigned char decimalPlaces)
{
init();
char buf[33];
*this = dtostrf(value, (decimalPlaces + 2), decimalPlaces, buf);
}
String::~String()
{
free(buffer);
}
/*********************************************/
/* Memory Management */
/*********************************************/
inline void String::init(void)
{
buffer = NULL;
capacity = 0;
len = 0;
}
void String::invalidate(void)
{
if (buffer) free(buffer);
buffer = NULL;
capacity = len = 0;
}
unsigned char String::reserve(unsigned int size)
{
if (buffer && capacity >= size) return 1;
if (changeBuffer(size)) {
if (len == 0) buffer[0] = 0;
return 1;
}
return 0;
}
unsigned char String::changeBuffer(unsigned int maxStrLen)
{
char *newbuffer = (char *)realloc(buffer, maxStrLen + 1);
if (newbuffer) {
buffer = newbuffer;
capacity = maxStrLen;
return 1;
}
return 0;
}
/*********************************************/
/* Copy and Move */
/*********************************************/
String & String::copy(const char *cstr, unsigned int length)
{
if (!reserve(length)) {
invalidate();
return *this;
}
len = length;
strcpy(buffer, cstr);
return *this;
}
String & String::copy(const __FlashStringHelper *pstr, unsigned int length)
{
if (!reserve(length)) {
invalidate();
return *this;
}
len = length;
strcpy_P(buffer, (PGM_P)pstr);
return *this;
}
#ifdef __GXX_EXPERIMENTAL_CXX0X__
void String::move(String &rhs)
{
if (buffer) {
if (capacity >= rhs.len) {
strcpy(buffer, rhs.buffer);
len = rhs.len;
rhs.len = 0;
return;
} else {
free(buffer);
}
}
buffer = rhs.buffer;
capacity = rhs.capacity;
len = rhs.len;
rhs.buffer = NULL;
rhs.capacity = 0;
rhs.len = 0;
}
#endif
String & String::operator = (const String &rhs)
{
if (this == &rhs) return *this;
if (rhs.buffer) copy(rhs.buffer, rhs.len);
else invalidate();
return *this;
}
#ifdef __GXX_EXPERIMENTAL_CXX0X__
String & String::operator = (String &&rval)
{
if (this != &rval) move(rval);
return *this;
}
String & String::operator = (StringSumHelper &&rval)
{
if (this != &rval) move(rval);
return *this;
}
#endif
String & String::operator = (const char *cstr)
{
if (cstr) copy(cstr, strlen(cstr));
else invalidate();
return *this;
}
String & String::operator = (const __FlashStringHelper *pstr)
{
if (pstr) copy(pstr, strlen_P((PGM_P)pstr));
else invalidate();
return *this;
}
/*********************************************/
/* concat */
/*********************************************/
unsigned char String::concat(const String &s)
{
return concat(s.buffer, s.len);
}
unsigned char String::concat(const char *cstr, unsigned int length)
{
unsigned int newlen = len + length;
if (!cstr) return 0;
if (length == 0) return 1;
if (!reserve(newlen)) return 0;
strcpy(buffer + len, cstr);
len = newlen;
return 1;
}
unsigned char String::concat(const char *cstr)
{
if (!cstr) return 0;
return concat(cstr, strlen(cstr));
}
unsigned char String::concat(char c)
{
char buf[2];
buf[0] = c;
buf[1] = 0;
return concat(buf, 1);
}
unsigned char String::concat(unsigned char num)
{
char buf[1 + 3 * sizeof(unsigned char)];
itoa(num, buf, 10);
return concat(buf, strlen(buf));
}
unsigned char String::concat(int num)
{
char buf[2 + 3 * sizeof(int)];
itoa(num, buf, 10);
return concat(buf, strlen(buf));
}
unsigned char String::concat(unsigned int num)
{
char buf[1 + 3 * sizeof(unsigned int)];
utoa(num, buf, 10);
return concat(buf, strlen(buf));
}
unsigned char String::concat(long num)
{
char buf[2 + 3 * sizeof(long)];
ltoa(num, buf, 10);
return concat(buf, strlen(buf));
}
unsigned char String::concat(unsigned long num)
{
char buf[1 + 3 * sizeof(unsigned long)];
ultoa(num, buf, 10);
return concat(buf, strlen(buf));
}
unsigned char String::concat(float num)
{
char buf[20];
char* string = dtostrf(num, 4, 2, buf);
return concat(string, strlen(string));
}
unsigned char String::concat(double num)
{
char buf[20];
char* string = dtostrf(num, 4, 2, buf);
return concat(string, strlen(string));
}
unsigned char String::concat(const __FlashStringHelper * str)
{
if (!str) return 0;
int length = strlen_P((const char *) str);
if (length == 0) return 1;
unsigned int newlen = len + length;
if (!reserve(newlen)) return 0;
strcpy_P(buffer + len, (const char *) str);
len = newlen;
return 1;
}
/*********************************************/
/* Concatenate */
/*********************************************/
StringSumHelper & operator + (const StringSumHelper &lhs, const String &rhs)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(rhs.buffer, rhs.len)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, const char *cstr)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!cstr || !a.concat(cstr, strlen(cstr))) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, char c)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(c)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, unsigned char num)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(num)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, int num)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(num)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, unsigned int num)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(num)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, long num)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(num)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, unsigned long num)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(num)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, float num)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(num)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, double num)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(num)) a.invalidate();
return a;
}
StringSumHelper & operator + (const StringSumHelper &lhs, const __FlashStringHelper *rhs)
{
StringSumHelper &a = const_cast<StringSumHelper&>(lhs);
if (!a.concat(rhs)) a.invalidate();
return a;
}
/*********************************************/
/* Comparison */
/*********************************************/
int String::compareTo(const String &s) const
{
if (!buffer || !s.buffer) {
if (s.buffer && s.len > 0) return 0 - *(unsigned char *)s.buffer;
if (buffer && len > 0) return *(unsigned char *)buffer;
return 0;
}
return strcmp(buffer, s.buffer);
}
unsigned char String::equals(const String &s2) const
{
return (len == s2.len && compareTo(s2) == 0);
}
unsigned char String::equals(const char *cstr) const
{
if (len == 0) return (cstr == NULL || *cstr == 0);
if (cstr == NULL) return buffer[0] == 0;
return strcmp(buffer, cstr) == 0;
}
unsigned char String::operator<(const String &rhs) const
{
return compareTo(rhs) < 0;
}
unsigned char String::operator>(const String &rhs) const
{
return compareTo(rhs) > 0;
}
unsigned char String::operator<=(const String &rhs) const
{
return compareTo(rhs) <= 0;
}
unsigned char String::operator>=(const String &rhs) const
{
return compareTo(rhs) >= 0;
}
unsigned char String::equalsIgnoreCase( const String &s2 ) const
{
if (this == &s2) return 1;
if (len != s2.len) return 0;
if (len == 0) return 1;
const char *p1 = buffer;
const char *p2 = s2.buffer;
while (*p1) {
if (tolower(*p1++) != tolower(*p2++)) return 0;
}
return 1;
}
unsigned char String::startsWith( const String &s2 ) const
{
if (len < s2.len) return 0;
return startsWith(s2, 0);
}
unsigned char String::startsWith( const String &s2, unsigned int offset ) const
{
if (offset > len - s2.len || !buffer || !s2.buffer) return 0;
return strncmp( &buffer[offset], s2.buffer, s2.len ) == 0;
}
unsigned char String::endsWith( const String &s2 ) const
{
if ( len < s2.len || !buffer || !s2.buffer) return 0;
return strcmp(&buffer[len - s2.len], s2.buffer) == 0;
}
/*********************************************/
/* Character Access */
/*********************************************/
char String::charAt(unsigned int loc) const
{
return operator[](loc);
}
void String::setCharAt(unsigned int loc, char c)
{
if (loc < len) buffer[loc] = c;
}
char & String::operator[](unsigned int index)
{
static char dummy_writable_char;
if (index >= len || !buffer) {
dummy_writable_char = 0;
return dummy_writable_char;
}
return buffer[index];
}
char String::operator[]( unsigned int index ) const
{
if (index >= len || !buffer) return 0;
return buffer[index];
}
void String::getBytes(unsigned char *buf, unsigned int bufsize, unsigned int index) const
{
if (!bufsize || !buf) return;
if (index >= len) {
buf[0] = 0;
return;
}
unsigned int n = bufsize - 1;
if (n > len - index) n = len - index;
strncpy((char *)buf, buffer + index, n);
buf[n] = 0;
}
/*********************************************/
/* Search */
/*********************************************/
int String::indexOf(char c) const
{
return indexOf(c, 0);
}
int String::indexOf( char ch, unsigned int fromIndex ) const
{
if (fromIndex >= len) return -1;
const char* temp = strchr(buffer + fromIndex, ch);
if (temp == NULL) return -1;
return temp - buffer;
}
int String::indexOf(const String &s2) const
{
return indexOf(s2, 0);
}
int String::indexOf(const String &s2, unsigned int fromIndex) const
{
if (fromIndex >= len) return -1;
const char *found = strstr(buffer + fromIndex, s2.buffer);
if (found == NULL) return -1;
return found - buffer;
}
int String::lastIndexOf( char theChar ) const
{
return lastIndexOf(theChar, len - 1);
}
int String::lastIndexOf(char ch, unsigned int fromIndex) const
{
if (fromIndex >= len) return -1;
char tempchar = buffer[fromIndex + 1];
buffer[fromIndex + 1] = '\0';
char* temp = strrchr( buffer, ch );
buffer[fromIndex + 1] = tempchar;
if (temp == NULL) return -1;
return temp - buffer;
}
int String::lastIndexOf(const String &s2) const
{
return lastIndexOf(s2, len - s2.len);
}
int String::lastIndexOf(const String &s2, unsigned int fromIndex) const
{
if (s2.len == 0 || len == 0 || s2.len > len) return -1;
if (fromIndex >= len) fromIndex = len - 1;
int found = -1;
for (char *p = buffer; p <= buffer + fromIndex; p++) {
p = strstr(p, s2.buffer);
if (!p) break;
if ((unsigned int)(p - buffer) <= fromIndex) found = p - buffer;
}
return found;
}
String String::substring(unsigned int left, unsigned int right) const
{
if (left > right) {
unsigned int temp = right;
right = left;
left = temp;
}
String out;
if (left >= len) return out;
if (right > len) right = len;
char temp = buffer[right]; // save the replaced character
buffer[right] = '\0';
out = buffer + left; // pointer arithmetic
buffer[right] = temp; //restore character
return out;
}
/*********************************************/
/* Modification */
/*********************************************/
void String::replace(char find, char replace)
{
if (!buffer) return;
for (char *p = buffer; *p; p++) {
if (*p == find) *p = replace;
}
}
void String::replace(const String& find, const String& replace)
{
if (len == 0 || find.len == 0) return;
int diff = replace.len - find.len;
char *readFrom = buffer;
char *foundAt;
if (diff == 0) {
while ((foundAt = strstr(readFrom, find.buffer)) != NULL) {
memcpy(foundAt, replace.buffer, replace.len);
readFrom = foundAt + replace.len;
}
} else if (diff < 0) {
char *writeTo = buffer;
while ((foundAt = strstr(readFrom, find.buffer)) != NULL) {
unsigned int n = foundAt - readFrom;
memcpy(writeTo, readFrom, n);
writeTo += n;
memcpy(writeTo, replace.buffer, replace.len);
writeTo += replace.len;
readFrom = foundAt + find.len;
len += diff;
}
strcpy(writeTo, readFrom);
} else {
unsigned int size = len; // compute size needed for result
while ((foundAt = strstr(readFrom, find.buffer)) != NULL) {
readFrom = foundAt + find.len;
size += diff;
}
if (size == len) return;
if (size > capacity && !changeBuffer(size)) return; // XXX: tell user!
int index = len - 1;
while (index >= 0 && (index = lastIndexOf(find, index)) >= 0) {
readFrom = buffer + index + find.len;
memmove(readFrom + diff, readFrom, len - (readFrom - buffer));
len += diff;
buffer[len] = 0;
memcpy(buffer + index, replace.buffer, replace.len);
index--;
}
}
}
void String::remove(unsigned int index){
// Pass the biggest integer as the count. The remove method
// below will take care of truncating it at the end of the
// string.
remove(index, (unsigned int)-1);
}
void String::remove(unsigned int index, unsigned int count){
if (index >= len) { return; }
if (count <= 0) { return; }
if (count > len - index) { count = len - index; }
char *writeTo = buffer + index;
len = len - count;
strncpy(writeTo, buffer + index + count,len - index);
buffer[len] = 0;
}
void String::toLowerCase(void)
{
if (!buffer) return;
for (char *p = buffer; *p; p++) {
*p = tolower(*p);
}
}
void String::toUpperCase(void)
{
if (!buffer) return;
for (char *p = buffer; *p; p++) {
*p = toupper(*p);
}
}
void String::trim(void)
{
if (!buffer || len == 0) return;
char *begin = buffer;
while (isspace(*begin)) begin++;
char *end = buffer + len - 1;
while (isspace(*end) && end >= begin) end--;
len = end + 1 - begin;
if (begin > buffer) memcpy(buffer, begin, len);
buffer[len] = 0;
}
/*********************************************/
/* Parsing / Conversion */
/*********************************************/
long String::toInt(void) const
{
if (buffer) return atol(buffer);
return 0;
}
float String::toFloat(void) const
{
if (buffer) return float(atof(buffer));
return 0;
}
更多建議和問題歡迎反饋至 YFRobot論壇
