Paolo Bonzini <pbonzini@redhat.com> writes:
> Rust makes the current file available as a statically-allocated string,
> but without a NUL terminator. Allow this by storing an optional maximum
> length in the Error.
>
> Note that for portability I am not relying on fprintf's precision
> specifier not accessing memory beyond what will be printed.
Stale paragraph :)
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> include/qapi/error-internal.h | 1 +
> util/error.c | 5 +++--
> 2 files changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/include/qapi/error-internal.h b/include/qapi/error-internal.h
> index d5c3904adec..f5eb8ad2379 100644
> --- a/include/qapi/error-internal.h
> +++ b/include/qapi/error-internal.h
> @@ -19,6 +19,7 @@ struct Error
> char *msg;
> ErrorClass err_class;
> const char *src, *func;
> + int src_len;
In actual usage, we have two cases:
* @src_len is -1 and @src is null-terminated
* @src_len is non-negative and @src is an array of at least that many
characters, not necessarily null-terminated
This is locally unobvious, and therefore deserves a comment.
Unterminated char * pretty much always deserve one :)
> int line;
> GString *hint;
> };
> diff --git a/util/error.c b/util/error.c
> index e5bcb7c0225..3449ecc0b92 100644
> --- a/util/error.c
> +++ b/util/error.c
> @@ -24,8 +24,8 @@ Error *error_warn;
> static void error_handle(Error **errp, Error *err)
> {
> if (errp == &error_abort) {
> - fprintf(stderr, "Unexpected error in %s() at %s:%d:\n",
> - err->func, err->src, err->line);
> + fprintf(stderr, "Unexpected error in %s() at %.*s:%d:\n",
> + err->func, err->src_len, err->src, err->line);
> error_report("%s", error_get_pretty(err));
> if (err->hint) {
> error_printf("%s", err->hint->str);
> @@ -67,6 +67,7 @@ static void error_setv(Error **errp,
> g_free(msg);
> }
> err->err_class = err_class;
> + err->src_len = -1;
> err->src = src;
> err->line = line;
> err->func = func;
This part looks fine to me.