add support for protocol driver create_options

This patch enables protocol drivers to use their create options which
are not supported by the format.  For example, protcol drivers can use
a backing_file option with raw format.

Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 46 insertions, 7 deletions

diff --git a/qemu-option.c b/qemu-option.c
index 076dddfc02..acd74f9124 100644
--- a/qemu-option.c
+++ b/qemu-option.c
@@ -346,6 +346,51 @@ void free_option_parameters(QEMUOptionParameter *list)
 }
 
 /*
+ * Count valid options in list
+ */
+static size_t count_option_parameters(QEMUOptionParameter *list)
+{
+    size_t num_options = 0;
+
+    while (list && list->name) {
+        num_options++;
+        list++;
+    }
+
+    return num_options;
+}
+
+/*
+ * Append an option list (list) to an option list (dest).
+ *
+ * If dest is NULL, a new copy of list is created.
+ *
+ * Returns a pointer to the first element of dest (or the newly allocated copy)
+ */
+QEMUOptionParameter *append_option_parameters(QEMUOptionParameter *dest,
+    QEMUOptionParameter *list)
+{
+    size_t num_options, num_dest_options;
+
+    num_options = count_option_parameters(dest);
+    num_dest_options = num_options;
+
+    num_options += count_option_parameters(list);
+
+    dest = qemu_realloc(dest, (num_options + 1) * sizeof(QEMUOptionParameter));
+
+    while (list && list->name) {
+        if (get_option_parameter(dest, list->name) == NULL) {
+            dest[num_dest_options++] = *list;
+            dest[num_dest_options].name = NULL;
+        }
+        list++;
+    }
+
+    return dest;
+}
+
+/*
  * Parses a parameter string (param) into an option list (dest).
  *
  * list is the templace is. If dest is NULL, a new copy of list is created for
@@ -365,7 +410,6 @@ void free_option_parameters(QEMUOptionParameter *list)
 QEMUOptionParameter *parse_option_parameters(const char *param,
     QEMUOptionParameter *list, QEMUOptionParameter *dest)
 {
-    QEMUOptionParameter *cur;
     QEMUOptionParameter *allocated = NULL;
     char name[256];
     char value[256];
@@ -379,12 +423,7 @@ QEMUOptionParameter *parse_option_parameters(const char *param,
 
     if (dest == NULL) {
         // Count valid options
-        num_options = 0;
-        cur = list;
-        while (cur->name) {
-            num_options++;
-            cur++;
-        }
+        num_options = count_option_parameters(list);
 
         // Create a copy of the option list to fill in values
         dest = qemu_mallocz((num_options + 1) * sizeof(QEMUOptionParameter));