[llvm-commits] [llvm] r120984 - in /llvm/trunk/include/llvm/ADT: SmallString.h SmallVector.h

[Michael Spencer]

On Sun, Dec 5, 2010 at 11:40 PM, Chris Lattner <clattner at apple.com> wrote:
>
> On Dec 5, 2010, at 8:27 PM, Michael J. Spencer wrote:
>
>> Author: mspencer
>> Date: Sun Dec  5 22:27:42 2010
>> New Revision: 120984
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=120984&view=rev
>> Log:
>> Support/ADT: Move c_str() from SmallString to SmallVectorImpl. The Windows PathV2
>> implementation needs it for wchar_t and SmallVectorImpl in general.
>
> Hi Michael,
>
> I don't think this makes sense, why not just cast data?  With wchar_t you usually need a multibyte 0 anyway.
>
> -Chris

c_str() as implemented uses push_back to add the 0, thus we get a
sizeof(wchar_t) byte null terminator. The reason this is needed is
because I kept running into bugs trying to keep track of when I needed
to add a null terminator. This way I can use c_str() exactly when
passing the string to a Windows API function.

- Michael Spencer

>>
>> Modified:
>>    llvm/trunk/include/llvm/ADT/SmallString.h
>>    llvm/trunk/include/llvm/ADT/SmallVector.h
>>
>> Modified: llvm/trunk/include/llvm/ADT/SmallString.h
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/SmallString.h?rev=120984&r1=120983&r2=120984&view=diff
>> ==============================================================================
>> --- llvm/trunk/include/llvm/ADT/SmallString.h (original)
>> +++ llvm/trunk/include/llvm/ADT/SmallString.h Sun Dec  5 22:27:42 2010
>> @@ -41,12 +41,6 @@
>>   // Implicit conversion to StringRef.
>>   operator StringRef() const { return str(); }
>>
>> -  const char *c_str() {
>> -    this->push_back(0);
>> -    this->pop_back();
>> -    return this->data();
>> -  }
>> -
>>   // Extra operators.
>>   const SmallString &operator=(StringRef RHS) {
>>     this->clear();
>>
>> Modified: llvm/trunk/include/llvm/ADT/SmallVector.h
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/SmallVector.h?rev=120984&r1=120983&r2=120984&view=diff
>> ==============================================================================
>> --- llvm/trunk/include/llvm/ADT/SmallVector.h (original)
>> +++ llvm/trunk/include/llvm/ADT/SmallVector.h Sun Dec  5 22:27:42 2010
>> @@ -340,6 +340,12 @@
>>     return Result;
>>   }
>>
>> +  // TODO: Make this const, if it's safe...
>> +  typename SuperClass::const_pointer c_str() {
>> +    push_back(0);
>> +    pop_back();
>> +    return this->data();
>> +  }
>>
>>   void swap(SmallVectorImpl &RHS);