arduino/esp8266
1
0
Fork 0
mirror of https://github.com/esp8266/Arduino.git synced 2025-07-16 00:43:00 +03:00
Code Activity

Fix String::replace() garbage at end of string (#5897)

Browse Source 
* Fix String::replace() 

Fixes #5883 and supercedes #5890

The replace() function was using len() while in the middle of buffer
operations.  In SSO mode len() is not stored separately and is a call to
strlen(), which may not be legal if you're in the middle of overwriting
the SSO buffer, as was the case in ::replace when the replacement string
was longer than the find string.  This caused potential garbage at the
end of the string when accessed.  Instead, just cache the length in a
local while doing the operation.

Add in test cases from #5890 as well as some new ones that fail on the
unmodified core.

* Fix stack smashing error on 64b

When pointers are 8 bytes long, the size of a String is larger than 16
chars.  Increase the allocated array we're using in the test to avoid a
"stack smashing" error.

* Manually call destructor in test

Just for clarity, manually call the destructor for the Strings() that
are "placement new'd" in the String tests.  It is a no-op for the
existing test, since thanks to SSO there are no memory allocations, but
will help in case someone adds tests later which include longer strings.
This commit is contained in:
Earle F. Philhower, III
2019-03-20 06:18:04 -07:00
committed by GitHub
parent 64e30b270b
commit 54240d2cc5
2 changed files with 70 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
cores/esp8266/WString.cpp
View File

@ -759,9 +759,10 @@ void String::replace(const String& find, const String& replace) {
while(index >= 0 && (index = lastIndexOf(find, index)) >= 0) {
readFrom = wbuffer() + index + find.len();
memmove(readFrom + diff, readFrom, len() - (readFrom - buffer()));
setLen(len() + diff);
wbuffer()[len()] = 0;
int newLen = len() + diff;
memcpy(wbuffer() + index, replace.buffer(), replace.len());
setLen(newLen);
wbuffer()[newLen] = 0;
index--;
}
}