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mirror of https://github.com/esp8266/Arduino.git synced 2025-04-22 21:23:07 +03:00
esp8266/cores/esp8266/WString.cpp
Earle F. Philhower, III 9c846bd52e
Fix concat not 0-terminating when String shrunk (#4962)
As @devyte noticed, PR #4955 has an issue when you catenate a string to
itself and the string used to hold a longer value because it does not
explicitly 0-terminate the resulting string.  If the string was extended,
however, reserve() would 0-terminate by default.

Always terminate the result of `s += s;` now.
2018-07-26 09:07:28 -07:00

799 lines
20 KiB
C++

/*
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
Modified by Ivan Grokhotkov, 2014 - esp8266 support
Modified by Michael C. Miller, 2015 - esp8266 progmem support
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 <Arduino.h>
#include "WString.h"
#include "stdlib_noniso.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; // see operator =
}
#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)];
if (base == 10) {
sprintf(buf, "%d", value);
} else {
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)];
if (base==10) {
sprintf(buf, "%ld", value);
} else {
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() {
invalidate();
}
// /*********************************************/
// /* Memory Management */
// /*********************************************/
inline void String::init(void) {
buffer = NULL;
capacity = 0;
len = 0;
}
void String::invalidate(void) {
if(buffer)
free(buffer);
init();
}
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) {
size_t newSize = (maxStrLen + 16) & (~0xf);
char *newbuffer = (char *) realloc(buffer, newSize);
if(newbuffer) {
size_t oldSize = capacity + 1; // include NULL.
if (newSize > oldSize)
{
memset(newbuffer + oldSize, 0, newSize - oldSize);
}
capacity = newSize - 1;
buffer = newbuffer;
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) {
// Special case if we're concatting ourself (s += s;) since we may end up
// realloc'ing the buffer and moving s.buffer in the method called
if (&s == this) {
unsigned int newlen = 2 * len;
if (!s.buffer)
return 0;
if (s.len == 0)
return 1;
if (!reserve(newlen))
return 0;
memcpy(buffer + len, buffer, len);
len = newlen;
buffer[len] = 0;
return 1;
} else {
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)];
sprintf(buf, "%d", num);
return concat(buf, strlen(buf));
}
unsigned char String::concat(int num) {
char buf[2 + 3 * sizeof(int)];
sprintf(buf, "%d", num);
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)];
sprintf(buf, "%ld", num);
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((PGM_P)str);
if (length == 0) return 1;
unsigned int newlen = len + length;
if (!reserve(newlen)) return 0;
strcpy_P(buffer + len, (PGM_P)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::equalsConstantTime(const String &s2) const {
// To avoid possible time-based attacks present function
// compares given strings in a constant time.
if(len != s2.len)
return 0;
//at this point lengths are the same
if(len == 0)
return 1;
//at this point lenghts are the same and non-zero
const char *p1 = buffer;
const char *p2 = s2.buffer;
unsigned int equalchars = 0;
unsigned int diffchars = 0;
while(*p1) {
if(*p1 == *p2)
++equalchars;
else
++diffchars;
++p1;
++p2;
}
//the following should force a constant time eval of the condition without a compiler "logical shortcut"
unsigned char equalcond = (equalchars == len);
unsigned char diffcond = (diffchars == 0);
return (equalcond & diffcond); //bitwise AND
}
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;
memmove(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)
memmove(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 atof(buffer);
return 0;
}