[libvirt] [PATCH 1/2] util: adding virHasLastError and virGetLastErrorCode/Domain

[ramyelkest]

Many places in the code call virGetLastError() just to check the
raised error code, or domain. However virGetLastError() can return
NULL, so the code has to check for that as well.

So Instead we create functions virGetLastErrorCode and virGetLastErrorDomain
(in addition to the existing virGetLastErrorMessage) that always return a
valid error code/domain/message, to simplify callers.

Also created virHasLastErrorCode for completion

My first commit, for:
https://wiki.libvirt.org/page/BiteSizedTasks#Add_and_use_virGetLastErrorCode.28.29

Signed-off-by: Ramy Elkest <ramyelkest at gmail.com>
---
 include/libvirt/virterror.h |  3 +++
 src/libvirt_public.syms     |  7 +++++
 src/util/virerror.c         | 63 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 73 insertions(+)

diff --git a/include/libvirt/virterror.h b/include/libvirt/virterror.h
index 3e7c7a0..8336258 100644
--- a/include/libvirt/virterror.h
+++ b/include/libvirt/virterror.h
@@ -344,6 +344,9 @@ void                    virResetLastError       (void);
 void                    virResetError           (virErrorPtr err);
 void                    virFreeError            (virErrorPtr err);
 
+int                     virHasLastError         (void);
+int                     virGetLastErrorCode     (void);
+int                     virGetLastErrorDomain   (void);
 const char *            virGetLastErrorMessage  (void);
 
 virErrorPtr             virConnGetLastError     (virConnectPtr conn);
diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
index 95df3a0..3a641a3 100644
--- a/src/libvirt_public.syms
+++ b/src/libvirt_public.syms
@@ -785,4 +785,11 @@ LIBVIRT_4.1.0 {
         virStoragePoolLookupByTargetPath;
 } LIBVIRT_3.9.0;
 
+LIBVIRT_4.4.0 {
+    global:
+        virHasLastError;
+        virGetLastErrorCode;
+        virGetLastErrorDomain;
+} LIBVIRT_4.1.0;
+
 # .... define new API here using predicted next version number ....
diff --git a/src/util/virerror.c b/src/util/virerror.c
index c000b00..818af2e 100644
--- a/src/util/virerror.c
+++ b/src/util/virerror.c
@@ -272,6 +272,69 @@ virGetLastError(void)
 
 
 /**
+ * virHasLastError:
+ *
+ * Check for a reported last error
+ *
+ * The error object is kept in thread local storage, so separate
+ * threads can safely access this concurrently.
+ *
+ * Returns 1 if there is an error and the error code is not VIR_ERR_OK,
+   otherwise returns 0
+ */
+int
+virHasLastError(void)
+{
+    virErrorPtr err = virLastErrorObject();
+    if (!err || err->code == VIR_ERR_OK)
+        return 0;
+    return 1;
+}
+
+
+/**
+ * virGetLastErrorCode:
+ *
+ * Get the most recent error code
+ *
+ * The error object is kept in thread local storage, so separate
+ * threads can safely access this concurrently.
+ *
+ * Returns the most recent error code in this thread,
+ * or VIR_ERR_OK if none is set
+ */
+int
+virGetLastErrorCode(void)
+{
+    virErrorPtr err = virLastErrorObject();
+    if (!err)
+        return VIR_ERR_OK;
+    return err->code;
+}
+
+
+/**
+ * virGetLastErrorDomain:
+ *
+ * Get the most recent error domain
+ *
+ * The error object is kept in thread local storage, so separate
+ * threads can safely access this concurrently.
+ *
+ * Returns the most recent error code in this thread,
+ * or VIR_FROM_NONE if none is set
+ */
+int
+virGetLastErrorDomain(void)
+{
+    virErrorPtr err = virLastErrorObject();
+    if (!err)
+        return VIR_FROM_NONE;
+    return err->domain;
+}
+
+
+/**
  * virGetLastErrorMessage:
  *
  * Get the most recent error message
-- 
2.7.4