util: Add helper to assign typed params from string

This patch adds a helper to deal with assigning values to
virTypedParameter structures from strings. The helper parses the value
from the string and assigns it to the corresponding union value.

src/libvirt_private.syms

@@ -1733,6 +1733,7 @@ virTimeStringThenRaw;
 virTypedParameterArrayClear;
 virTypedParameterArrayValidate;
 virTypedParameterAssign;
+virTypedParameterAssignFromStr;
 
 
 # viruri.h

src/util/virtypedparam.c

@@ -181,3 +181,100 @@ cleanup:
     va_end(ap);
     return ret;
 }
+
+/* Assign name, type, and convert the argument from a const string.
+ * In case of a string, the string is copied.
+ * Return 0 on success, -1 after an error message on failure.  */
+int
+virTypedParameterAssignFromStr(virTypedParameterPtr param, const char *name,
+                               int type, const char *val)
+{
+    int ret = -1;
+
+    if (!val) {
+        virReportError(VIR_ERR_INVALID_ARG, _("NULL value for field '%s'"),
+                       name);
+        goto cleanup;
+    }
+
+    if (virStrcpyStatic(param->field, name) == NULL) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, _("Field name '%s' too long"),
+                       name);
+        goto cleanup;
+    }
+
+    param->type = type;
+    switch (type) {
+    case VIR_TYPED_PARAM_INT:
+        if (virStrToLong_i(val, NULL, 10, &param->value.i) < 0) {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("Invalid value for field '%s': expected int"),
+                           name);
+            goto cleanup;
+        }
+        break;
+    case VIR_TYPED_PARAM_UINT:
+        if (virStrToLong_ui(val, NULL, 10, &param->value.ui) < 0) {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("Invalid value for field '%s': "
+                             "expected unsigned int"),
+                           name);
+            goto cleanup;
+        }
+        break;
+    case VIR_TYPED_PARAM_LLONG:
+        if (virStrToLong_ll(val, NULL, 10, &param->value.l) < 0) {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("Invalid value for field '%s': "
+                             "expected long long"),
+                           name);
+            goto cleanup;
+        }
+        break;
+    case VIR_TYPED_PARAM_ULLONG:
+        if (virStrToLong_ull(val, NULL, 10, &param->value.ul) < 0) {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("Invalid value for field '%s': "
+                             "expected unsigned long long"),
+                           name);
+            goto cleanup;
+        }
+        break;
+    case VIR_TYPED_PARAM_DOUBLE:
+        if (virStrToDouble(val, NULL, &param->value.d) < 0) {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("Invalid value for field '%s': "
+                             "expected double"),
+                           name);
+            goto cleanup;
+        }
+        break;
+    case VIR_TYPED_PARAM_BOOLEAN:
+        if (STRCASEEQ(val, "true") ||
+            STREQ(val, "1")) {
+            param->value.b = true;
+        } else if (STRCASEEQ(val, "false") ||
+                 STREQ(val, "0")) {
+            param->value.b = false;
+        } else {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("Invalid boolean value for field '%s'"), name);
+            goto cleanup;
+        }
+        break;
+    case VIR_TYPED_PARAM_STRING:
+        if (!(param->value.s = strdup(val))) {
+            virReportOOMError();
+            goto cleanup;
+        }
+        break;
+    default:
+        virReportError(VIR_ERR_INTERNAL_ERROR,
+                       _("unexpected type %d for field %s"), type, name);
+        goto cleanup;
+    }
+
+    ret = 0;
+cleanup:
+    return ret;
+}

src/util/virtypedparam.h

@@ -35,4 +35,10 @@ int virTypedParameterAssign(virTypedParameterPtr param, const char *name,
                             int type, /* TYPE arg */ ...)
     ATTRIBUTE_RETURN_CHECK;
 
+int virTypedParameterAssignFromStr(virTypedParameterPtr param,
+                                   const char *name,
+                                   int type,
+                                   const char *val)
+    ATTRIBUTE_RETURN_CHECK;
+
 #endif /* __VIR_TYPED_PARAM_H */