2 files changed, 36 insertions, 18 deletions

diff --git a/util/qemu-config.c b/util/qemu-config.c
index 30d6dcf526..6cfdd7204a 100644
--- a/util/qemu-config.c
+++ b/util/qemu-config.c
@@ -6,7 +6,7 @@
 #include "qapi/error.h"
 #include "qmp-commands.h"
 
-static QemuOptsList *vm_config_groups[32];
+static QemuOptsList *vm_config_groups[48];
 static QemuOptsList *drive_config_groups[4];
 
 static QemuOptsList *find_list(QemuOptsList **lists, const char *group,
@@ -335,7 +335,8 @@ struct ConfigWriteData {
     FILE *fp;
 };
 
-static int config_write_opt(const char *name, const char *value, void *opaque)
+static int config_write_opt(void *opaque, const char *name, const char *value,
+                            Error **errp)
 {
     struct ConfigWriteData *data = opaque;
 
@@ -343,7 +344,7 @@ static int config_write_opt(const char *name, const char *value, void *opaque)
     return 0;
 }
 
-static int config_write_opts(QemuOpts *opts, void *opaque)
+static int config_write_opts(void *opaque, QemuOpts *opts, Error **errp)
 {
     struct ConfigWriteData *data = opaque;
     const char *id = qemu_opts_id(opts);
@@ -353,7 +354,7 @@ static int config_write_opts(QemuOpts *opts, void *opaque)
     } else {
         fprintf(data->fp, "[%s]\n", data->list->name);
     }
-    qemu_opt_foreach(opts, config_write_opt, data, 0);
+    qemu_opt_foreach(opts, config_write_opt, data, NULL);
     fprintf(data->fp, "\n");
     return 0;
 }
@@ -367,7 +368,7 @@ void qemu_config_write(FILE *fp)
     fprintf(fp, "# qemu config file\n\n");
     for (i = 0; lists[i] != NULL; i++) {
         data.list = lists[i];
-        qemu_opts_foreach(data.list, config_write_opts, &data, 0);
+        qemu_opts_foreach(data.list, config_write_opts, &data, NULL);
     }
 }
 
diff --git a/util/qemu-option.c b/util/qemu-option.c
index fda4e5fcbf..840f5f7a5b 100644
--- a/util/qemu-option.c
+++ b/util/qemu-option.c
@@ -596,18 +596,26 @@ void qemu_opt_set_number(QemuOpts *opts, const char *name, int64_t val,
     QTAILQ_INSERT_TAIL(&opts->head, opt, next);
 }
 
+/**
+ * For each member of @opts, call @func(@opaque, name, value, @errp).
+ * @func() may store an Error through @errp, but must return non-zero then.
+ * When @func() returns non-zero, break the loop and return that value.
+ * Return zero when the loop completes.
+ */
 int qemu_opt_foreach(QemuOpts *opts, qemu_opt_loopfunc func, void *opaque,
-                     int abort_on_failure)
+                     Error **errp)
 {
     QemuOpt *opt;
-    int rc = 0;
+    int rc;
 
     QTAILQ_FOREACH(opt, &opts->head, next) {
-        rc = func(opt->name, opt->str, opaque);
-        if (abort_on_failure  &&  rc != 0)
-            break;
+        rc = func(opaque, opt->name, opt->str, errp);
+        if (rc) {
+            return rc;
+        }
+        assert(!errp || !*errp);
     }
-    return rc;
+    return 0;
 }
 
 QemuOpts *qemu_opts_find(QemuOptsList *list, const char *id)
@@ -1046,22 +1054,31 @@ void qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
     }
 }
 
-int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque,
-                      int abort_on_failure)
+/**
+ * For each member of @list, call @func(@opaque, member, @errp).
+ * Call it with the current location temporarily set to the member's.
+ * @func() may store an Error through @errp, but must return non-zero then.
+ * When @func() returns non-zero, break the loop and return that value.
+ * Return zero when the loop completes.
+ */
+int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
+                      void *opaque, Error **errp)
 {
     Location loc;
     QemuOpts *opts;
-    int rc = 0;
+    int rc;
 
     loc_push_none(&loc);
     QTAILQ_FOREACH(opts, &list->head, next) {
         loc_restore(&opts->loc);
-        rc |= func(opts, opaque);
-        if (abort_on_failure  &&  rc != 0)
-            break;
+        rc = func(opaque, opts, errp);
+        if (rc) {
+            return rc;
+        }
+        assert(!errp || !*errp);
     }
     loc_pop(&loc);
-    return rc;
+    return 0;
 }
 
 static size_t count_opts_list(QemuOptsList *list)