util: virtypedparam: Store errors inside virTypedParamList

The only non-abort()-ing error which can happen is if the field name is
too long. Store the overly long name in the virTypedParamList container
so that in upcoming patches the helpers adding to the list can be
refactored to not have a return value.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

src/util/virtypedparam.c

@@ -709,6 +709,8 @@ struct _virTypedParamList {
     virTypedParameterPtr par;
     size_t npar;
     size_t par_alloc;
+
+    char *err_name; /* overly long field name for error message */
 };
 
 
@@ -739,6 +741,9 @@ virTypedParamListConcat(virTypedParamList *to,
     memcpy(to->par + to->npar, from->par, sizeof(*(to->par)) * from->npar);
     to->npar += from->npar;
     from->npar = 0;
+
+    if (!to->err_name)
+        to->err_name = g_steal_pointer(&from->err_name);
 }
 
 
@@ -749,6 +754,7 @@ virTypedParamListFree(virTypedParamList *list)
         return;
 
     virTypedParamsFree(list->par, list->npar);
+    g_free(list->err_name);
     g_free(list);
 }
 
@@ -769,6 +775,12 @@ virTypedParamListFetch(virTypedParamList *list,
                        virTypedParameterPtr *par,
                        size_t *npar)
 {
+    if (list->err_name) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, _("Field name '%1$s' too long"),
+                       list->err_name);
+        return -1;
+    }
+
     if (par)
         *par = list->par;
 
@@ -814,17 +826,18 @@ virTypedParamListFromParams(virTypedParameterPtr *params,
 }
 
 
-static int G_GNUC_PRINTF(2, 0)
+static void G_GNUC_PRINTF(3, 0)
-virTypedParamSetNameVPrintf(virTypedParameterPtr par,
+virTypedParamSetNameVPrintf(virTypedParamList *list,
+                            virTypedParameterPtr par,
                             const char *fmt,
                             va_list ap)
 {
-    if (g_vsnprintf(par->field, VIR_TYPED_PARAM_FIELD_LENGTH, fmt, ap) > VIR_TYPED_PARAM_FIELD_LENGTH) {
+    g_autofree char *name = g_strdup_vprintf(fmt, ap);
-        virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("Field name too long"));
-        return -1;
-    }
 
-    return 0;
+    if (virStrcpyStatic(par->field, name) < 0) {
+        if (!list->err_name)
+            list->err_name = g_steal_pointer(&name);
+    }
 }
 
 
@@ -847,15 +860,14 @@ virTypedParamListAddInt(virTypedParamList *list,
 {
     virTypedParameterPtr par = virTypedParamListExtend(list);
     va_list ap;
-    int ret;
 
     virTypedParameterAssignValue(par, VIR_TYPED_PARAM_INT, value);
 
     va_start(ap, namefmt);
-    ret = virTypedParamSetNameVPrintf(par, namefmt, ap);
+    virTypedParamSetNameVPrintf(list, par, namefmt, ap);
     va_end(ap);
 
-    return ret;
+    return 0;
 }
 
 
@@ -867,15 +879,14 @@ virTypedParamListAddUInt(virTypedParamList *list,
 {
     virTypedParameterPtr par = virTypedParamListExtend(list);
     va_list ap;
-    int ret;
 
     virTypedParameterAssignValue(par, VIR_TYPED_PARAM_UINT, value);
 
     va_start(ap, namefmt);
-    ret = virTypedParamSetNameVPrintf(par, namefmt, ap);
+    virTypedParamSetNameVPrintf(list, par, namefmt, ap);
     va_end(ap);
 
-    return ret;
+    return 0;
 }
 
 
@@ -887,15 +898,14 @@ virTypedParamListAddLLong(virTypedParamList *list,
 {
     virTypedParameterPtr par = virTypedParamListExtend(list);
     va_list ap;
-    int ret;
 
     virTypedParameterAssignValue(par, VIR_TYPED_PARAM_LLONG, value);
 
     va_start(ap, namefmt);
-    ret = virTypedParamSetNameVPrintf(par, namefmt, ap);
+    virTypedParamSetNameVPrintf(list, par, namefmt, ap);
     va_end(ap);
 
-    return ret;
+    return 0;
 }
 
 
@@ -907,15 +917,14 @@ virTypedParamListAddULLong(virTypedParamList *list,
 {
     virTypedParameterPtr par = virTypedParamListExtend(list);
     va_list ap;
-    int ret;
 
     virTypedParameterAssignValue(par, VIR_TYPED_PARAM_ULLONG, value);
 
     va_start(ap, namefmt);
-    ret = virTypedParamSetNameVPrintf(par, namefmt, ap);
+    virTypedParamSetNameVPrintf(list, par, namefmt, ap);
     va_end(ap);
 
-    return ret;
+    return 0;
 }
 
 
@@ -927,15 +936,14 @@ virTypedParamListAddString(virTypedParamList *list,
 {
     virTypedParameterPtr par = virTypedParamListExtend(list);
     va_list ap;
-    int ret;
 
     virTypedParameterAssignValue(par, VIR_TYPED_PARAM_STRING, value);
 
     va_start(ap, namefmt);
-    ret = virTypedParamSetNameVPrintf(par, namefmt, ap);
+    virTypedParamSetNameVPrintf(list, par, namefmt, ap);
     va_end(ap);
 
-    return ret;
+    return 0;
 }
 
 
@@ -947,15 +955,14 @@ virTypedParamListAddBoolean(virTypedParamList *list,
 {
     virTypedParameterPtr par = virTypedParamListExtend(list);
     va_list ap;
-    int ret;
 
     virTypedParameterAssignValue(par, VIR_TYPED_PARAM_BOOLEAN, value);
 
     va_start(ap, namefmt);
-    ret = virTypedParamSetNameVPrintf(par, namefmt, ap);
+    virTypedParamSetNameVPrintf(list, par, namefmt, ap);
     va_end(ap);
 
-    return ret;
+    return 0;
 }
 
 
@@ -967,13 +974,12 @@ virTypedParamListAddDouble(virTypedParamList *list,
 {
     virTypedParameterPtr par = virTypedParamListExtend(list);
     va_list ap;
-    int ret;
 
     virTypedParameterAssignValue(par, VIR_TYPED_PARAM_DOUBLE, value);
 
     va_start(ap, namefmt);
-    ret = virTypedParamSetNameVPrintf(par, namefmt, ap);
+    virTypedParamSetNameVPrintf(list, par, namefmt, ap);
     va_end(ap);
 
-    return ret;
+    return 0;
 }