On Fri, 2022-11-04 at 17:05 -0400, Lewis Hyatt wrote:
> [PATCH 5b/6] diagnostics: Remove null-termination requirement for
> json::string
>
> json::string currently handles null-terminated data and so can't work
> with
> data that may contain embedded null bytes or that is not null-
> terminated.
> Supporting such data will make json::string more robust in some
> contexts, such
> as SARIF output, which uses it to output user source code that may
> contain
> embedded null bytes.
>
> gcc/ChangeLog:
>
> * json.h (class string): Add M_LEN member to store the
> length of
> the data. Add constructor taking an explicit length.
> * json.cc (string::string): Implement the new constructor.
> (string::print): Support print strings that are not null-
> terminated.
> Escape embdedded null bytes on output.
> (test_writing_strings): Test the new null-byte-related
> features of
> json::string.
>
[...snip...]
> diff --git a/gcc/json.h b/gcc/json.h
> index f272981259b..f7afd843dc5 100644
> --- a/gcc/json.h
> +++ b/gcc/json.h
> @@ -156,16 +156,19 @@ class integer_number : public value
> class string : public value
> {
> public:
> - string (const char *utf8);
> + explicit string (const char *utf8);
> + string (const char *utf8, size_t len);
> ~string () { free (m_utf8); }
>
> enum kind get_kind () const final override { return JSON_STRING; }
> void print (pretty_printer *pp) const final override;
>
> const char *get_string () const { return m_utf8; }
I worried that json::string::get_string previously returned a NUL-
terminated string, but now there's no guarantee of termination, and
that this might break something. But I checked, and it seems that this
accessor doesn't get used anywhere in our source tree.
> + size_t get_length () const { return m_len; }
Does anything actually use this?
Perhaps it might make sense to delete the get_string accessor, and if
we ever need one, replace it with an accessor that returns a char_span?
>
> private:
> char *m_utf8;
> + size_t m_len;
> };
>
Thanks for adding the unit test.
The 5b patch is OK for trunk.
Dave
