From 65cd9064e13f2388d3bd9c815826f5db6b0b13ec Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Fri, 25 Apr 2014 12:44:22 +0200 Subject: [PATCH] qom: Clean up fragile use of error_is_set() in set() methods MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 84d18f0). I guess the error_is_set(errp) in the ObjectProperty set() methods are merely fragile right now, because I can't find a call chain that passes 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: Markus Armbruster Signed-off-by: Andreas Färber --- backends/rng.c | 11 +++++++---- backends/tpm.c | 11 +++++++---- hw/core/qdev-properties.c | 11 +++++++---- hw/misc/tmp105.c | 6 ++++-- hw/virtio/virtio-balloon.c | 6 ++++-- target-i386/cpu.c | 24 ++++++++++++++++-------- 6 files changed, 45 insertions(+), 24 deletions(-) diff --git a/backends/rng.c b/backends/rng.c index 8b8d5a4973..0f2fc11dd8 100644 --- a/backends/rng.c +++ b/backends/rng.c @@ -50,6 +50,7 @@ static void rng_backend_prop_set_opened(Object *obj, bool value, Error **errp) { RngBackend *s = RNG_BACKEND(obj); RngBackendClass *k = RNG_BACKEND_GET_CLASS(s); + Error *local_err = NULL; if (value == s->opened) { return; @@ -61,12 +62,14 @@ static void rng_backend_prop_set_opened(Object *obj, bool value, Error **errp) } if (k->opened) { - k->opened(s, errp); + k->opened(s, &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } } - if (!error_is_set(errp)) { - s->opened = value; - } + s->opened = true; } static void rng_backend_init(Object *obj) diff --git a/backends/tpm.c b/backends/tpm.c index b73580134c..01860c4acb 100644 --- a/backends/tpm.c +++ b/backends/tpm.c @@ -112,6 +112,7 @@ static void tpm_backend_prop_set_opened(Object *obj, bool value, Error **errp) { TPMBackend *s = TPM_BACKEND(obj); TPMBackendClass *k = TPM_BACKEND_GET_CLASS(s); + Error *local_err = NULL; if (value == s->opened) { return; @@ -123,12 +124,14 @@ static void tpm_backend_prop_set_opened(Object *obj, bool value, Error **errp) } if (k->opened) { - k->opened(s, errp); + k->opened(s, &local_err); + if (local_err) { + error_propagate(errp, local_err); + return; + } } - if (!error_is_set(errp)) { - s->opened = value; - } + s->opened = true; } static void tpm_backend_instance_init(Object *obj) diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c index 585a8e902e..d8cb5408c3 100644 --- a/hw/core/qdev-properties.c +++ b/hw/core/qdev-properties.c @@ -751,6 +751,7 @@ static void set_prop_arraylen(Object *obj, Visitor *v, void *opaque, Property *prop = opaque; uint32_t *alenptr = qdev_get_prop_ptr(dev, prop); void **arrayptr = (void *)dev + prop->arrayoffset; + Error *local_err = NULL; void *eltptr; const char *arrayname; int i; @@ -764,8 +765,9 @@ static void set_prop_arraylen(Object *obj, Visitor *v, void *opaque, name); return; } - visit_type_uint32(v, alenptr, name, errp); - if (error_is_set(errp)) { + visit_type_uint32(v, alenptr, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } if (!*alenptr) { @@ -802,8 +804,9 @@ static void set_prop_arraylen(Object *obj, Visitor *v, void *opaque, arrayprop->prop.info->get, arrayprop->prop.info->set, array_element_release, - arrayprop, errp); - if (error_is_set(errp)) { + arrayprop, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } } diff --git a/hw/misc/tmp105.c b/hw/misc/tmp105.c index 63aa3d6277..636ee97b16 100644 --- a/hw/misc/tmp105.c +++ b/hw/misc/tmp105.c @@ -68,10 +68,12 @@ static void tmp105_set_temperature(Object *obj, Visitor *v, void *opaque, const char *name, Error **errp) { TMP105State *s = TMP105(obj); + Error *local_err = NULL; int64_t temp; - visit_type_int(v, &temp, name, errp); - if (error_is_set(errp)) { + visit_type_int(v, &temp, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } if (temp >= 128000 || temp < -128000) { diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index a470a0b3a6..971a921777 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -142,10 +142,12 @@ static void balloon_stats_set_poll_interval(Object *obj, struct Visitor *v, Error **errp) { VirtIOBalloon *s = opaque; + Error *local_err = NULL; int64_t value; - visit_type_int(v, &value, name, errp); - if (error_is_set(errp)) { + visit_type_int(v, &value, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } diff --git a/target-i386/cpu.c b/target-i386/cpu.c index 8fd1497dc4..8f193a9330 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -1300,10 +1300,12 @@ static void x86_cpuid_version_set_family(Object *obj, Visitor *v, void *opaque, CPUX86State *env = &cpu->env; const int64_t min = 0; const int64_t max = 0xff + 0xf; + Error *local_err = NULL; int64_t value; - visit_type_int(v, &value, name, errp); - if (error_is_set(errp)) { + visit_type_int(v, &value, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } if (value < min || value > max) { @@ -1339,10 +1341,12 @@ static void x86_cpuid_version_set_model(Object *obj, Visitor *v, void *opaque, CPUX86State *env = &cpu->env; const int64_t min = 0; const int64_t max = 0xff; + Error *local_err = NULL; int64_t value; - visit_type_int(v, &value, name, errp); - if (error_is_set(errp)) { + visit_type_int(v, &value, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } if (value < min || value > max) { @@ -1375,10 +1379,12 @@ static void x86_cpuid_version_set_stepping(Object *obj, Visitor *v, CPUX86State *env = &cpu->env; const int64_t min = 0; const int64_t max = 0xf; + Error *local_err = NULL; int64_t value; - visit_type_int(v, &value, name, errp); - if (error_is_set(errp)) { + visit_type_int(v, &value, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } if (value < min || value > max) { @@ -1511,10 +1517,12 @@ static void x86_cpuid_set_tsc_freq(Object *obj, Visitor *v, void *opaque, X86CPU *cpu = X86_CPU(obj); const int64_t min = 0; const int64_t max = INT64_MAX; + Error *local_err = NULL; int64_t value; - visit_type_int(v, &value, name, errp); - if (error_is_set(errp)) { + visit_type_int(v, &value, name, &local_err); + if (local_err) { + error_propagate(errp, local_err); return; } if (value < min || value > max) { -- 2.39.2