Commit 0aff637e authored by Markus Armbruster's avatar Markus Armbruster Committed by Gerd Hoffmann
Browse files

char: Clean up fragile use of error_is_set() 



Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque.  It's wrong when ERRP
may be null, because errors go undetected when it is.  It's fragile
when proving ERRP non-null involves a non-local argument.  Else, it's
unnecessarily opaque (see commit 84d18f06).

The error_is_set(errp) in qemu_chr_new_from_opts() is merely fragile,
because the callers never pass a null errp argument.

Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.

Signed-off-by: default avatarMarkus Armbruster <armbru@redhat.com>
Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
parent 5f758366

qemu-char.c

+4 −2
Original line number Diff line number Diff line
@@ -3204,6 +3204,7 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts, 
                                    void (*init)(struct CharDriverState *s),

                                    Error **errp)

{

    Error *local_err = NULL;

    CharDriver *cd;

    CharDriverState *chr;

    GSList *i;
@@ -3245,8 +3246,9 @@ CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts, 
        chr = NULL;

        backend->kind = cd->kind;

        if (cd->parse) {

            cd->parse(opts, backend, errp);

            if (error_is_set(errp)) {

            cd->parse(opts, backend, &local_err);

            if (local_err) {

                error_propagate(errp, local_err);

                goto qapi_out;

            }

        }