[Mesa-dev] [PATCH 3/3] clover: unsure compat::string is \0 terminated

[Francisco Jerez]

EdB <edb+mesa at sigluy.net> writes:

> otherwise c_str() is not safe
> ---
>  src/gallium/state_trackers/clover/util/compat.hpp | 54 ++++++++++++++++++++---
>  1 file changed, 48 insertions(+), 6 deletions(-)
>
> diff --git a/src/gallium/state_trackers/clover/util/compat.hpp b/src/gallium/state_trackers/clover/util/compat.hpp
> index 6f0f7cc..7ca1f85 100644
> --- a/src/gallium/state_trackers/clover/util/compat.hpp
> +++ b/src/gallium/state_trackers/clover/util/compat.hpp
> @@ -197,7 +197,7 @@ namespace clover {
>              return _p[i];
>           }
>  
> -      private:
> +      protected:
>           iterator _p;  //memory array
>           size_type _s; //size
>           size_type _c; //capacity
> @@ -306,18 +306,56 @@ namespace clover {
>  
>        class string : public vector<char> {
>        public:
> -         string() : vector() {
> +         string() : vector(0, 1) {
> +            _p[_s - 1] = '\0';
>           }
>  
> -         string(const char *p) : vector(p, std::strlen(p)) {
> +         string(const char *p) : vector(p, std::strlen(p) + 1) {
> +            _p[_s - 1] = '\0';
>           }
>  
>           template<typename C>
> -         string(const C &v) : vector(v) {
> +         string(const C &v) : vector(&*v.begin(), v.size() + 1) {
> +            _p[_s - 1] = '\0';
>           }
>  
> -         operator std::string() const {
> -            return std::string(begin(), end());
> +         void
> +         reserve(size_type m) {
> +            vector::reserve(m + 1);
> +         }
> +
> +         void
> +         resize(size_type m, char x = '\0') {
> +            vector::resize(m + 1, x);
> +            _p[_s - 1] = '\0';
> +         }
> +
> +         void
> +         push_back(char &x) {
> +            reserve(_s + 1);
> +            _p[_s - 1] = x;
> +            _p[_s] = '\0';
> +            ++_s;
> +         }
> +
> +         size_type
> +         size() const {
> +            return _s - 1;
> +         }
> +
> +         size_type
> +         capacity() const {
> +            return _c - 1;
> +         }
> +
> +         iterator
> +         end() {
> +            return _p + size();
> +         }
> +
> +         const_iterator
> +         end() const {
> +            return _p + size();
>           }
>  

At this point where all methods from the base class need to be redefined
it probably stops making sense to use inheritance instead of
aggregation.  Once we've done that fixing c_str() gets a lot easier (two
lines of code) because we can just declare the container as mutable and
fix up the NULL terminator when c_str() is called.  Both changes
attached.

>           const char *
> @@ -325,6 +363,10 @@ namespace clover {
>              return begin();
>           }
>  
> +         operator std::string() const {
> +            return std::string(begin(), end());
> +         }
> +
>           const char *
>           find(const string &s) const {
>              for (size_t i = 0; i + s.size() < size(); ++i) {
> -- 
> 2.0.4
>
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/mesa-dev

-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-clover-util-Implement-compat-string-using-aggregatio.patch
Type: text/x-diff
Size: 2820 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/mesa-dev/attachments/20140818/0da5a124/attachment-0002.patch>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0002-clover-util-Null-terminate-the-result-of-compat-stri.patch
Type: text/x-diff
Size: 915 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/mesa-dev/attachments/20140818/0da5a124/attachment-0003.patch>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 212 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/mesa-dev/attachments/20140818/0da5a124/attachment-0001.sig>