ch: Add monitor portion of resize cpu.

Use the newly introduced virCHMonitorPut and add logic to build the
json for Cloud-Hypervisor.

Author: bryteise

src/ch/ch_monitor.c

@@ -496,6 +496,15 @@ virCHMonitorBuildDevicesJson(virJSONValuePtr content, virDomainDefPtr vmdef)
     return -1;
 }
 
+static int
+virCHMonitorBuildResizeCPUsJson(virJSONValuePtr content, unsigned int nvcpus)
+{
+    if (virJSONValueObjectAppendNumberUint(content, "desired_vcpus", nvcpus) < 0)
+        return -1;
+
+    return 0;
+}
+
 static int
 virCHMonitorBuildVMJson(virDomainObjPtr vm, virDomainDefPtr vmdef, char **jsonstr,
                         size_t *nnicindexes, int **nicindexes)
@@ -547,6 +556,26 @@ virCHMonitorBuildVMJson(virDomainObjPtr vm, virDomainDefPtr vmdef, char **jsonst
     return ret;
 }
 
+static int
+virCHMonitorBuildResizeJson(const unsigned int nvcpus,
+                            char **jsonstr)
+{
+    virJSONValuePtr content = virJSONValueNewObject();
+    int ret = -1;
+
+    if (virCHMonitorBuildResizeCPUsJson(content, nvcpus) < 0)
+        goto cleanup;
+
+    if (!(*jsonstr = virJSONValueToString(content, false)))
+        goto cleanup;
+
+    ret = 0;
+
+ cleanup:
+    virJSONValueFree(content);
+    return ret;
+}
+
 /* generate command to launch Cloud-Hypervisor socket
    return -1 - error
            0 - OK
@@ -1530,6 +1559,17 @@ virCHMonitorPingVMM(virCHMonitorPtr mon)
     return virCHMonitorGet(mon, URL_VMM_PING, NULL);
 }
 
+int
+virCHMonitorResizeCPU(virCHMonitorPtr mon,
+                      unsigned int nvcpus)
+{
+    g_autofree char *payload = NULL;
+    if (virCHMonitorBuildResizeJson(nvcpus, &payload))
+        return -1;
+
+    return virCHMonitorPut(mon, URL_VM_RESIZE, payload);
+}
+
 int
 virCHMonitorShutdownVMM(virCHMonitorPtr mon)
 {

src/ch/ch_monitor.h

@@ -30,6 +30,7 @@
 #define URL_VMM_SHUTDOWN "vmm.shutdown"
 #define URL_VMM_PING "vmm.ping"
 #define URL_VM_CREATE "vm.create"
+#define URL_VM_RESIZE "vm.resize"
 #define URL_VM_DELETE "vm.delete"
 #define URL_VM_BOOT "vm.boot"
 #define URL_VM_SHUTDOWN "vm.shutdown"
@@ -173,3 +174,7 @@ int virCHMonitorGetIOThreads(virCHMonitorPtr mon,
                             virDomainIOThreadInfoPtr **iothreads);
 
 int virCHMonitorGetInfo(virCHMonitorPtr mon, virJSONValuePtr *info);
+
+int
+virCHMonitorResizeCPU(virCHMonitorPtr mon,
+                      unsigned int nvcpus);