qemu_capabilities: Change virQEMUCapsFillDomainCaps signature

Up till now the virQEMUCapsFillDomainCaps() was type of void as
there was no way for it to fail. This is, however, going to
change in the next commit.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_capabilities.c

@@ -3608,7 +3608,7 @@ virQEMUCapsGetDefaultMachine(virQEMUCapsPtr qemuCaps)
 }
 
 
-static void
+static int
 virQEMUCapsFillDomainLoaderCaps(virQEMUCapsPtr qemuCaps,
                                 virDomainCapsLoaderPtr loader,
                                 virArch arch)
@@ -3629,10 +3629,11 @@ virQEMUCapsFillDomainLoaderCaps(virQEMUCapsPtr qemuCaps,
         VIR_DOMAIN_CAPS_ENUM_SET(loader->readonly,
                                  VIR_TRISTATE_BOOL_YES,
                                  VIR_TRISTATE_BOOL_NO);
+    return 0;
 }
 
 
-static void
+static int
 virQEMUCapsFillDomainOSCaps(virQEMUCapsPtr qemuCaps,
                             virDomainCapsOSPtr os,
                             virArch arch)
@@ -3640,11 +3641,13 @@ virQEMUCapsFillDomainOSCaps(virQEMUCapsPtr qemuCaps,
     virDomainCapsLoaderPtr loader = &os->loader;
 
     os->device.supported = true;
-    virQEMUCapsFillDomainLoaderCaps(qemuCaps, loader, arch);
+    if (virQEMUCapsFillDomainLoaderCaps(qemuCaps, loader, arch) < 0)
+        return -1;
+    return 0;
 }
 
 
-static void
+static int
 virQEMUCapsFillDomainDeviceDiskCaps(virQEMUCapsPtr qemuCaps,
                                     virDomainCapsDeviceDiskPtr disk)
 {
@@ -3667,10 +3670,11 @@ virQEMUCapsFillDomainDeviceDiskCaps(virQEMUCapsPtr qemuCaps,
 
     if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_USB_STORAGE))
         VIR_DOMAIN_CAPS_ENUM_SET(disk->bus, VIR_DOMAIN_DISK_BUS_USB);
+    return 0;
 }
 
 
-static void
+static int
 virQEMUCapsFillDomainDeviceHostdevCaps(virQEMUCapsPtr qemuCaps,
                                        virDomainCapsDeviceHostdevPtr hostdev)
 {
@@ -3715,10 +3719,11 @@ virQEMUCapsFillDomainDeviceHostdevCaps(virQEMUCapsPtr qemuCaps,
                                  VIR_DOMAIN_HOSTDEV_PCI_BACKEND_DEFAULT,
                                  VIR_DOMAIN_HOSTDEV_PCI_BACKEND_KVM);
     }
+    return 0;
 }
 
 
-void
+int
 virQEMUCapsFillDomainCaps(virDomainCapsPtr domCaps,
                           virQEMUCapsPtr qemuCaps)
 {
@@ -3729,7 +3734,9 @@ virQEMUCapsFillDomainCaps(virDomainCapsPtr domCaps,
 
     domCaps->maxvcpus = maxvcpus;
 
-    virQEMUCapsFillDomainOSCaps(qemuCaps, os, domCaps->arch);
+    if (virQEMUCapsFillDomainOSCaps(qemuCaps, os, domCaps->arch) < 0 ||
-    virQEMUCapsFillDomainDeviceDiskCaps(qemuCaps, disk);
+        virQEMUCapsFillDomainDeviceDiskCaps(qemuCaps, disk) < 0 ||
-    virQEMUCapsFillDomainDeviceHostdevCaps(qemuCaps, hostdev);
+        virQEMUCapsFillDomainDeviceHostdevCaps(qemuCaps, hostdev) < 0)
+        return -1;
+    return 0;
 }

src/qemu/qemu_capabilities.h

@@ -324,7 +324,7 @@ int virQEMUCapsInitGuestFromBinary(virCapsPtr caps,
                                    virQEMUCapsPtr kvmbinCaps,
                                    virArch guestarch);
 
-void virQEMUCapsFillDomainCaps(virDomainCapsPtr domCaps,
+int virQEMUCapsFillDomainCaps(virDomainCapsPtr domCaps,
-                               virQEMUCapsPtr qemuCaps);
+                              virQEMUCapsPtr qemuCaps);
 
 #endif /* __QEMU_CAPABILITIES_H__*/

src/qemu/qemu_driver.c

@@ -17357,7 +17357,8 @@ qemuConnectGetDomainCapabilities(virConnectPtr conn,
     if (!(domCaps = virDomainCapsNew(emulatorbin, machine, arch, virttype)))
         goto cleanup;
 
-    virQEMUCapsFillDomainCaps(domCaps, qemuCaps);
+    if (virQEMUCapsFillDomainCaps(domCaps, qemuCaps) < 0)
+        goto cleanup;
 
     ret = virDomainCapsFormat(domCaps);
  cleanup:

tests/domaincapstest.c

@@ -28,13 +28,13 @@
 
 #define VIR_FROM_THIS VIR_FROM_NONE
 
-typedef void (*virDomainCapsFill)(virDomainCapsPtr domCaps,
+typedef int (*virDomainCapsFill)(virDomainCapsPtr domCaps,
-                                  void *opaque);
+                                 void *opaque);
 
 #define SET_ALL_BITS(x) \
     memset(&(x.values), 0xff, sizeof(x.values))
 
-static void
+static int
 fillAll(virDomainCapsPtr domCaps,
         void *opaque ATTRIBUTE_UNUSED)
 {
@@ -60,18 +60,20 @@ fillAll(virDomainCapsPtr domCaps,
     SET_ALL_BITS(hostdev->subsysType);
     SET_ALL_BITS(hostdev->capsType);
     SET_ALL_BITS(hostdev->pciBackend);
+    return 0;
 }
 
 
 #ifdef WITH_QEMU
 # include "testutilsqemu.h"
-static void
+static int
 fillQemuCaps(virDomainCapsPtr domCaps,
              void *opaque)
 {
     virQEMUCapsPtr qemuCaps = (virQEMUCapsPtr) opaque;
 
-    virQEMUCapsFillDomainCaps(domCaps, qemuCaps);
+    if (virQEMUCapsFillDomainCaps(domCaps, qemuCaps) < 0)
+        return -1;
 
     /* The function above tries to query host's KVM & VFIO capabilities by
      * calling qemuHostdevHostSupportsPassthroughLegacy() and
@@ -82,6 +84,7 @@ fillQemuCaps(virDomainCapsPtr domCaps,
                              VIR_DOMAIN_HOSTDEV_PCI_BACKEND_DEFAULT,
                              VIR_DOMAIN_HOSTDEV_PCI_BACKEND_KVM,
                              VIR_DOMAIN_HOSTDEV_PCI_BACKEND_VFIO);
+    return 0;
 }
 #endif /* WITH_QEMU */
 
@@ -99,8 +102,10 @@ buildVirDomainCaps(const char *emulatorbin,
     if (!(domCaps = virDomainCapsNew(emulatorbin, machine, arch, type)))
         goto cleanup;
 
-    if (fillFunc)
+    if (fillFunc && fillFunc(domCaps, opaque) < 0) {
-        fillFunc(domCaps, opaque);
+        virObjectUnref(domCaps);
+        domCaps = NULL;
+    }
 
  cleanup:
     return domCaps;