[libvirt] [go PATCH 25/37] nwfilter binding: fix error reporting thread safety

[Daniel P. Berrangé]

Create wrapper functions for each nwfilter binding C API that accepts a
virErrorPtr parameter. This avoids accessing a thread local from a
goroutine which may race with other goroutines doing native API calls in
the same OS thread.

Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
---
 nwfilter_binding.go         | 30 +++++++++++-------
 nwfilter_binding_wrapper.go | 63 +++++++++++++++++++++++++++++--------
 nwfilter_binding_wrapper.h  | 27 ++++++++++------
 3 files changed, 85 insertions(+), 35 deletions(-)

diff --git a/nwfilter_binding.go b/nwfilter_binding.go
index 722303b..5999d3e 100644
--- a/nwfilter_binding.go
+++ b/nwfilter_binding.go
@@ -45,9 +45,10 @@ func (f *NWFilterBinding) Free() error {
 	if C.LIBVIR_VERSION_NUMBER < 4005000 {
 		return GetNotImplementedError("virNWFilterBindingFree")
 	}
-	ret := C.virNWFilterBindingFreeWrapper(f.ptr)
+	var err C.virError
+	ret := C.virNWFilterBindingFreeWrapper(f.ptr, &err)
 	if ret == -1 {
-		return GetLastError()
+		return makeError(&err)
 	}
 	return nil
 }
@@ -57,9 +58,10 @@ func (c *NWFilterBinding) Ref() error {
 	if C.LIBVIR_VERSION_NUMBER < 4005000 {
 		return GetNotImplementedError("virNWFilterBindingRef")
 	}
-	ret := C.virNWFilterBindingRefWrapper(c.ptr)
+	var err C.virError
+	ret := C.virNWFilterBindingRefWrapper(c.ptr, &err)
 	if ret == -1 {
-		return GetLastError()
+		return makeError(&err)
 	}
 	return nil
 }
@@ -69,9 +71,10 @@ func (f *NWFilterBinding) Delete() error {
 	if C.LIBVIR_VERSION_NUMBER < 4005000 {
 		return GetNotImplementedError("virNWFilterBindingDelete")
 	}
-	result := C.virNWFilterBindingDeleteWrapper(f.ptr)
+	var err C.virError
+	result := C.virNWFilterBindingDeleteWrapper(f.ptr, &err)
 	if result == -1 {
-		return GetLastError()
+		return makeError(&err)
 	}
 	return nil
 }
@@ -81,9 +84,10 @@ func (f *NWFilterBinding) GetPortDev() (string, error) {
 	if C.LIBVIR_VERSION_NUMBER < 4005000 {
 		return "", GetNotImplementedError("virNWFilterBindingGetPortDev")
 	}
-	result := C.virNWFilterBindingGetPortDevWrapper(f.ptr)
+	var err C.virError
+	result := C.virNWFilterBindingGetPortDevWrapper(f.ptr, &err)
 	if result == nil {
-		return "", GetLastError()
+		return "", makeError(&err)
 	}
 	name := C.GoString(result)
 	C.free(unsafe.Pointer(result))
@@ -95,9 +99,10 @@ func (f *NWFilterBinding) GetFilterName() (string, error) {
 	if C.LIBVIR_VERSION_NUMBER < 4005000 {
 		return "", GetNotImplementedError("virNWFilterBindingGetFilterName")
 	}
-	result := C.virNWFilterBindingGetFilterNameWrapper(f.ptr)
+	var err C.virError
+	result := C.virNWFilterBindingGetFilterNameWrapper(f.ptr, &err)
 	if result == nil {
-		return "", GetLastError()
+		return "", makeError(&err)
 	}
 	name := C.GoString(result)
 	C.free(unsafe.Pointer(result))
@@ -109,9 +114,10 @@ func (f *NWFilterBinding) GetXMLDesc(flags uint32) (string, error) {
 	if C.LIBVIR_VERSION_NUMBER < 4005000 {
 		return "", GetNotImplementedError("virNWFilterBindingGetXMLDesc")
 	}
-	result := C.virNWFilterBindingGetXMLDescWrapper(f.ptr, C.uint(flags))
+	var err C.virError
+	result := C.virNWFilterBindingGetXMLDescWrapper(f.ptr, C.uint(flags), &err)
 	if result == nil {
-		return "", GetLastError()
+		return "", makeError(&err)
 	}
 	xml := C.GoString(result)
 	C.free(unsafe.Pointer(result))
diff --git a/nwfilter_binding_wrapper.go b/nwfilter_binding_wrapper.go
index fdafaef..b0950b5 100644
--- a/nwfilter_binding_wrapper.go
+++ b/nwfilter_binding_wrapper.go
@@ -30,63 +30,100 @@ package libvirt
 #include <assert.h>
 #include "nwfilter_binding_wrapper.h"
 
-const char *virNWFilterBindingGetPortDevWrapper(virNWFilterBindingPtr binding)
+
+int
+virNWFilterBindingDeleteWrapper(virNWFilterBindingPtr binding,
+                                virErrorPtr err)
 {
 #if LIBVIR_VERSION_NUMBER < 4005000
     assert(0); // Caller should have checked version
 #else
-    return virNWFilterBindingGetPortDev(binding);
+    int ret = virNWFilterBindingDelete(binding);
+    if (ret < 0) {
+        virCopyLastError(err);
+    }
+    return ret;
 #endif
 }
 
 
-const char *virNWFilterBindingGetFilterNameWrapper(virNWFilterBindingPtr binding)
+int
+virNWFilterBindingFreeWrapper(virNWFilterBindingPtr binding,
+                              virErrorPtr err)
 {
 #if LIBVIR_VERSION_NUMBER < 4005000
     assert(0); // Caller should have checked version
 #else
-    return virNWFilterBindingGetFilterName(binding);
+    int ret = virNWFilterBindingFree(binding);
+    if (ret < 0) {
+        virCopyLastError(err);
+    }
+    return ret;
 #endif
 }
 
 
-char *virNWFilterBindingGetXMLDescWrapper(virNWFilterBindingPtr binding,
-					 unsigned int flags)
+const char *
+virNWFilterBindingGetFilterNameWrapper(virNWFilterBindingPtr binding,
+                                       virErrorPtr err)
 {
 #if LIBVIR_VERSION_NUMBER < 4005000
     assert(0); // Caller should have checked version
 #else
-    return virNWFilterBindingGetXMLDesc(binding, flags);
+    const char * ret = virNWFilterBindingGetFilterName(binding);
+    if (!ret) {
+        virCopyLastError(err);
+    }
+    return ret;
 #endif
 }
 
 
-int virNWFilterBindingDeleteWrapper(virNWFilterBindingPtr binding)
+const char *
+virNWFilterBindingGetPortDevWrapper(virNWFilterBindingPtr binding,
+                                    virErrorPtr err)
 {
 #if LIBVIR_VERSION_NUMBER < 4005000
     assert(0); // Caller should have checked version
 #else
-    return virNWFilterBindingDelete(binding);
+    const char * ret = virNWFilterBindingGetPortDev(binding);
+    if (!ret) {
+        virCopyLastError(err);
+    }
+    return ret;
 #endif
 }
 
 
-int virNWFilterBindingRefWrapper(virNWFilterBindingPtr binding)
+char *
+virNWFilterBindingGetXMLDescWrapper(virNWFilterBindingPtr binding,
+                                    unsigned int flags,
+                                    virErrorPtr err)
 {
 #if LIBVIR_VERSION_NUMBER < 4005000
     assert(0); // Caller should have checked version
 #else
-    return virNWFilterBindingRef(binding);
+    char * ret = virNWFilterBindingGetXMLDesc(binding, flags);
+    if (!ret) {
+        virCopyLastError(err);
+    }
+    return ret;
 #endif
 }
 
 
-int virNWFilterBindingFreeWrapper(virNWFilterBindingPtr binding)
+int
+virNWFilterBindingRefWrapper(virNWFilterBindingPtr binding,
+                             virErrorPtr err)
 {
 #if LIBVIR_VERSION_NUMBER < 4005000
     assert(0); // Caller should have checked version
 #else
-    return virNWFilterBindingFree(binding);
+    int ret = virNWFilterBindingRef(binding);
+    if (ret < 0) {
+        virCopyLastError(err);
+    }
+    return ret;
 #endif
 }
 
diff --git a/nwfilter_binding_wrapper.h b/nwfilter_binding_wrapper.h
index 63942be..0bcbfb7 100644
--- a/nwfilter_binding_wrapper.h
+++ b/nwfilter_binding_wrapper.h
@@ -30,24 +30,31 @@
 #include <libvirt/virterror.h>
 #include "nwfilter_binding_compat.h"
 
+
+int
+virNWFilterBindingDeleteWrapper(virNWFilterBindingPtr binding,
+                                virErrorPtr err);
+
+int
+virNWFilterBindingFreeWrapper(virNWFilterBindingPtr binding,
+                              virErrorPtr err);
+
 const char *
-virNWFilterBindingGetPortDevWrapper(virNWFilterBindingPtr binding);
+virNWFilterBindingGetFilterNameWrapper(virNWFilterBindingPtr binding,
+                                       virErrorPtr err);
 
 const char *
-virNWFilterBindingGetFilterNameWrapper(virNWFilterBindingPtr binding);
+virNWFilterBindingGetPortDevWrapper(virNWFilterBindingPtr binding,
+                                    virErrorPtr err);
 
 char *
 virNWFilterBindingGetXMLDescWrapper(virNWFilterBindingPtr binding,
-                                    unsigned int flags);
-
-int
-virNWFilterBindingDeleteWrapper(virNWFilterBindingPtr binding);
-
-int
-virNWFilterBindingRefWrapper(virNWFilterBindingPtr binding);
+                                    unsigned int flags,
+                                    virErrorPtr err);
 
 int
-virNWFilterBindingFreeWrapper(virNWFilterBindingPtr binding);
+virNWFilterBindingRefWrapper(virNWFilterBindingPtr binding,
+                             virErrorPtr err);
 
 
 #endif /* LIBVIRT_GO_NWFILTER_BINDING_WRAPPER_H__ */
-- 
2.17.1