Re: [Monotone-devel] Patch to speed up add operation

[ml-monotone]

Benoît Dejean wrote:

(...)

> i can't find anything saying that string uses contiguous storage. Better
> use vector. So the following is buggy :
> 
> 
>     +    while(file.good()) 
>         +      {
>         +        buf.resize(bufsize);
>         +        file.read(&buf[0],bufsize);
>         +        buf.resize(file.gcount());

Allthough most (all?) STL implementations so far implement std::string 
using contiguous memory, the standard does not mandate it. Only the 
pointer returned by std::string::c_str() points to contiguous memory 
useable by C for reading only (valid only until next modification of 
that std::string instance).

Scott Meyers has stated, that the only container forseen to be used with 
C libraries is std::vector, where the trick above shall work.

(...)

> am I being to picky ? :)

I think it is good you mentioned it, as it has impact on portability.


Ciao,
Clemens.