[libvirt] [PATCH] qemu: Exit on first error in qemuDomainGetMemoryParameters

[Matthias Bolte]

There is no point in trying to fill params beyond the first error,
because when qemuDomainGetMemoryParameters returns -1 then the caller
cannot detect which values in params are valid.
---

There is a similar pattern in qemuDomainSetMemoryParameters that tries
to apply all given params even if one already failed. From a user's
POV it's probably better to apply all params without an error or to
apply non at all when one fails. But this is harder to implemeneted
and requires a rollback mechanism.

 src/qemu/qemu_driver.c |   21 ++++++++-------------
 1 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 6395c93..ae1d833 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -9676,7 +9676,6 @@ static int qemuDomainGetMemoryParameters(virDomainPtr dom,
         goto cleanup;
     }
 
-    ret = 0;
     for (i = 0; i < *nparams; i++) {
         virMemoryParameterPtr param = &params[i];
         val = 0;
@@ -9689,14 +9688,12 @@ static int qemuDomainGetMemoryParameters(virDomainPtr dom,
             if (rc != 0) {
                 virReportSystemError(-rc, "%s",
                                      _("unable to get memory hard limit"));
-                ret = -1;
-                continue;
+                goto cleanup;
             }
             if (virStrcpyStatic(param->field, VIR_DOMAIN_MEMORY_HARD_LIMIT) == NULL) {
                 qemuReportError(VIR_ERR_INTERNAL_ERROR,
                                 "%s", _("Field memory hard limit too long for destination"));
-                ret = -1;
-                continue;
+                goto cleanup;
             }
             param->value.ul = val;
             break;
@@ -9706,14 +9703,12 @@ static int qemuDomainGetMemoryParameters(virDomainPtr dom,
             if (rc != 0) {
                 virReportSystemError(-rc, "%s",
                                      _("unable to get memory soft limit"));
-                ret = -1;
-                continue;
+                goto cleanup;
             }
             if (virStrcpyStatic(param->field, VIR_DOMAIN_MEMORY_SOFT_LIMIT) == NULL) {
                 qemuReportError(VIR_ERR_INTERNAL_ERROR,
                                 "%s", _("Field memory soft limit too long for destination"));
-                ret = -1;
-                continue;
+                goto cleanup;
             }
             param->value.ul = val;
             break;
@@ -9723,14 +9718,12 @@ static int qemuDomainGetMemoryParameters(virDomainPtr dom,
             if (rc != 0) {
                 virReportSystemError(-rc, "%s",
                                      _("unable to get swap hard limit"));
-                ret = -1;
-                continue;
+                goto cleanup;
             }
             if (virStrcpyStatic(param->field, VIR_DOMAIN_MEMORY_SWAP_HARD_LIMIT) == NULL) {
                 qemuReportError(VIR_ERR_INTERNAL_ERROR,
                                 "%s", _("Field swap hard limit too long for destination"));
-                ret = -1;
-                continue;
+                goto cleanup;
             }
             param->value.ul = val;
             break;
@@ -9741,6 +9734,8 @@ static int qemuDomainGetMemoryParameters(virDomainPtr dom,
         }
     }
 
+    ret = 0;
+
 cleanup:
     if (group)
         virCgroupFree(&group);
-- 
1.7.0.4