lib/pb-config: Implement config_set

This change adds config_set, to allow the configuration to be updated,
but calling the storage backend's save() method.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

3 files changed, 36 insertions, 4 deletions

diff --git a/lib/pb-config/pb-config.c b/lib/pb-config/pb-config.c
index b6f26c7..1e53256 100644
--- a/lib/pb-config/pb-config.c
+++ b/lib/pb-config/pb-config.c
@@ -7,11 +7,12 @@
 
 #include "storage.h"
 
+void				*config_ctx;
 static struct config		*config;
 static struct config_storage	*storage;
 
 
-static void config_set_defaults(struct config *config)
+void config_set_defaults(struct config *config)
 {
 	config->autoboot_enabled = true;
 	config->autoboot_timeout_sec = 10;
@@ -28,7 +29,8 @@ static void config_set_defaults(struct config *config)
 
 }
 
-static void dump_config(struct config *config)
+void dump_config(struct config *config);
+void dump_config(struct config *config)
 {
 	int i;
 
@@ -73,7 +75,9 @@ static void dump_config(struct config *config)
 
 int config_init(void *ctx)
 {
-	config = talloc(ctx, struct config);
+	config_ctx = talloc_new(ctx);
+
+	config = talloc(config_ctx, struct config);
 	config_set_defaults(config);
 
 	storage = create_powerpc_nvram_storage(config);
@@ -85,6 +89,29 @@ int config_init(void *ctx)
 	return 0;
 }
 
+int config_set(struct config *newconfig)
+{
+	int rc;
+
+	if (!storage || !storage->save)
+		return -1;
+
+	if (newconfig == config)
+		return 0;
+
+	pb_log("new configuration data received\n");
+	dump_config(config);
+
+	rc = storage->save(storage, config);
+
+	if (!rc)
+		config = talloc_steal(config_ctx, newconfig);
+	else
+		pb_log("error saving new configuration; changes lost\n");
+
+	return rc;
+}
+
 /* A non-exported function to allow the test infrastructure to initialise
  * (and change) the configuration variables */
 struct parser_test;
@@ -112,6 +139,6 @@ void config_set_autoboot(bool autoboot_enabled)
 
 int config_fini(void)
 {
-	talloc_free(config);
+	talloc_free(config_ctx);
 	return 0;
 }
diff --git a/lib/pb-config/pb-config.h b/lib/pb-config/pb-config.h
index 523cada..90babaa 100644
--- a/lib/pb-config/pb-config.h
+++ b/lib/pb-config/pb-config.h
@@ -47,8 +47,12 @@ struct config {
 
 int config_init(void *ctx);
 const struct config *config_get(void);
+int config_set(struct config *config);
 void config_set_autoboot(bool autoboot_enabled);
 int config_fini(void);
 
+/* for use by the storage backends */
+void config_set_defaults(struct config *config);
+
 #endif /* CONFIGURATION_H */
 
diff --git a/lib/pb-config/storage.h b/lib/pb-config/storage.h
index a1d5269..5b4af56 100644
--- a/lib/pb-config/storage.h
+++ b/lib/pb-config/storage.h
@@ -7,6 +7,7 @@ struct config;
 
 struct config_storage {
 	int	(*load)(struct config_storage *st, struct config *config);
+	int	(*save)(struct config_storage *st, struct config *config);
 };
 
 struct config_storage *create_powerpc_nvram_storage(void *ctx);