[PATCH v2] tools: only fail validations if VIR_HOST_VALIDATE_FAIL is set

[Fabiano Fidêncio]

Currently `virt-host-validate` will fail whenever one of its calls fail,
regardless of virHostValidateLevel set.

This behaviour is not optimal and makes it not exactly reliable as a
command line tool as other tools or scripts using it would have to check
its output to figure out whether something really failed or if a warning
was mistakenly treated as failure.

With this change, the behaviour of whether to fail or not, is defined by
the caller of those functions, based on the virHostValidateLevel passed
to them.

https://gitlab.com/libvirt/libvirt/-/issues/175

Signed-off-by: Fabiano Fidêncio <fabiano at fidencio.org>
---
Changes since v1:
* Replace the `goto out;` and the `out` labels by the
  `VIR_HOST_VALIDATE_FAILURE` macro
---
 tools/virt-host-validate-common.c | 30 +++++++++++++++---------------
 tools/virt-host-validate-common.h | 14 ++++++++++++++
 2 files changed, 29 insertions(+), 15 deletions(-)

diff --git a/tools/virt-host-validate-common.c b/tools/virt-host-validate-common.c
index 6dd851f07d..9412bb7514 100644
--- a/tools/virt-host-validate-common.c
+++ b/tools/virt-host-validate-common.c
@@ -142,7 +142,7 @@ int virHostValidateDeviceExists(const char *hvname,
 
     if (access(dev_name, F_OK) < 0) {
         virHostMsgFail(level, "%s", hint);
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
 
     virHostMsgPass();
@@ -159,7 +159,7 @@ int virHostValidateDeviceAccessible(const char *hvname,
 
     if (access(dev_name, R_OK|W_OK) < 0) {
         virHostMsgFail(level, "%s", hint);
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
 
     virHostMsgPass();
@@ -180,7 +180,7 @@ int virHostValidateNamespace(const char *hvname,
 
     if (access(nspath, F_OK) < 0) {
         virHostMsgFail(level, "%s", hint);
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
 
     virHostMsgPass();
@@ -264,17 +264,17 @@ int virHostValidateLinuxKernel(const char *hvname,
 
     if (STRNEQ(uts.sysname, "Linux")) {
         virHostMsgFail(level, "%s", hint);
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
 
     if (virParseVersionString(uts.release, &thisversion, true) < 0) {
         virHostMsgFail(level, "%s", hint);
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
 
     if (thisversion < version) {
         virHostMsgFail(level, "%s", hint);
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     } else {
         virHostMsgPass();
         return 0;
@@ -291,7 +291,7 @@ int virHostValidateCGroupControllers(const char *hvname,
     size_t i;
 
     if (virCgroupNew("/", -1, &group) < 0)
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
 
     for (i = 0; i < VIR_CGROUP_CONTROLLER_LAST; i++) {
         int flag = 1 << i;
@@ -303,7 +303,7 @@ int virHostValidateCGroupControllers(const char *hvname,
         virHostMsgCheck(hvname, "for cgroup '%s' controller support", cg_name);
 
         if (!virCgroupHasController(group, i)) {
-            ret = -1;
+            ret = VIR_HOST_VALIDATE_FAILURE(level);
             virHostMsgFail(level, "Enable '%s' in kernel Kconfig file or "
                            "mount/enable cgroup controller in your system",
                            cg_name);
@@ -320,7 +320,7 @@ int virHostValidateCGroupControllers(const char *hvname G_GNUC_UNUSED,
                                      virHostValidateLevel level)
 {
     virHostMsgFail(level, "%s", "This platform does not support cgroups");
-    return -1;
+    return VIR_HOST_VALIDATE_FAILURE(level);
 }
 #endif /* !__linux__ */
 
@@ -354,7 +354,7 @@ int virHostValidateIOMMU(const char *hvname,
                            "No ACPI DMAR table found, IOMMU either "
                            "disabled in BIOS or not supported by this "
                            "hardware platform");
-            return -1;
+            return VIR_HOST_VALIDATE_FAILURE(level);
         }
     } else if (isAMD) {
         virHostMsgCheck(hvname, "%s", _("for device assignment IOMMU support"));
@@ -366,7 +366,7 @@ int virHostValidateIOMMU(const char *hvname,
                            "No ACPI IVRS table found, IOMMU either "
                            "disabled in BIOS or not supported by this "
                            "hardware platform");
-            return -1;
+            return VIR_HOST_VALIDATE_FAILURE(level);
         }
     } else if (ARCH_IS_PPC64(arch)) {
         /* Empty Block */
@@ -385,7 +385,7 @@ int virHostValidateIOMMU(const char *hvname,
     } else {
         virHostMsgFail(level,
                        "Unknown if this platform has IOMMU support");
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
 
 
@@ -404,7 +404,7 @@ int virHostValidateIOMMU(const char *hvname,
                            "Add %s to kernel cmdline arguments", bootarg);
         else
             virHostMsgFail(level, "IOMMU capability not compiled into kernel.");
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
     virHostMsgPass();
     return 0;
@@ -468,7 +468,7 @@ int virHostValidateSecureGuests(const char *hvname,
             }
 
             if (virFileReadValueString(&cmdline, "/proc/cmdline") < 0)
-                return -1;
+                return VIR_HOST_VALIDATE_FAILURE(level);
 
             /* we're prefix matching rather than equality matching here, because
              * kernel would treat even something like prot_virt='yFOO' as
@@ -516,7 +516,7 @@ int virHostValidateSecureGuests(const char *hvname,
     } else {
         virHostMsgFail(level,
                        "Unknown if this platform has Secure Guest support");
-        return -1;
+        return VIR_HOST_VALIDATE_FAILURE(level);
     }
 
     return 0;
diff --git a/tools/virt-host-validate-common.h b/tools/virt-host-validate-common.h
index 08a9997f5f..9334fa8588 100644
--- a/tools/virt-host-validate-common.h
+++ b/tools/virt-host-validate-common.h
@@ -45,6 +45,20 @@ typedef enum {
 
 VIR_ENUM_DECL(virHostValidateCPUFlag);
 
+/**
+ * VIR_HOST_VALIDATE_FAILURE
+ * @level: the virHostValidateLevel to be checked
+ *
+ * This macro is to be used in to return a failures based on the
+ * virHostValidateLevel use in the function.
+ *
+ * If the virHostValidateLevel is VIR_HOST_VALIDATE_FAIL, -1 is returned.
+ * 0 is returned otherwise (as the virHosValidateLevel is then either a
+ * Warn or a Note).
+ */
+
+#define VIR_HOST_VALIDATE_FAILURE(level) (level == VIR_HOST_VALIDATE_FAIL) ? -1 : 0
+
 void virHostMsgSetQuiet(bool quietFlag);
 
 void virHostMsgCheck(const char *prefix,
-- 
2.31.1