fix(plugins): make list_fields return a const pointer

The fields returned by a plugin can be a static string and the plugin framework doesn't have any business in modifying it so let's make it const (to avoid a copy for plugins that can return a static string). Note: I only bump the plugin API version by 0.0.1 since the changes in this PR do not affect binary compatibility in any way. Signed-off-by: Grzegorz Nosek <[email protected]>
falcosecurity · Mar 8, 2024 · 5f4f7ec · 5f4f7ec
1 parent 4abc96d
commit 5f4f7ec
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Showing 3 changed files with 6 additions and 6 deletions.
diff --git a/userspace/libsinsp/plugin_table_api.cpp b/userspace/libsinsp/plugin_table_api.cpp
@@ -734,7 +734,7 @@ struct sinsp_table_wrapper
 	const sinsp_plugin* m_table_plugin_owner;
 	ss_plugin_table_input* m_table_plugin_input;
 
-	static ss_plugin_table_fieldinfo* list_fields(ss_plugin_table_t* _t, uint32_t* nfields)
+	static const ss_plugin_table_fieldinfo* list_fields(ss_plugin_table_t* _t, uint32_t* nfields)
 	{
 		auto t = static_cast<sinsp_table_wrapper*>(_t);
 
@@ -1231,7 +1231,7 @@ ss_plugin_rc sinsp_table_wrapper::write_entry_field(ss_plugin_table_t* _t, ss_pl
 // For sinsp-defined tables, the ss_plugin_table_input is a wrapper around
 // the libsinsp::state::table interface. For plugin-defined tables, the
 // ss_plugin_table_input is provided by the table-owner plugin itself.
-static ss_plugin_table_fieldinfo* dispatch_list_fields(ss_plugin_table_t *_t, uint32_t *nfields)
+static const ss_plugin_table_fieldinfo* dispatch_list_fields(ss_plugin_table_t *_t, uint32_t *nfields)
 {
 	auto t = static_cast<ss_plugin_table_input*>(_t);
 	return t->fields_ext->list_table_fields(t->table, nfields);

diff --git a/userspace/libsinsp/test/plugins/sample_table.h b/userspace/libsinsp/test/plugins/sample_table.h
@@ -74,7 +74,7 @@ class sample_table
         return t->entries.size();
     }
 
-    static ss_plugin_table_fieldinfo* list_fields(ss_plugin_table_t* _t, uint32_t* nfields)
+    static const ss_plugin_table_fieldinfo* list_fields(ss_plugin_table_t* _t, uint32_t* nfields)
     {
         auto t = static_cast<sample_table*>(_t);
         *nfields = (uint32_t) t->fields.size();

diff --git a/userspace/plugin/plugin_api.h b/userspace/plugin/plugin_api.h
@@ -31,7 +31,7 @@ extern "C" {
 // todo(jasondellaluce): when/if major changes to v4, check and solve all todos
 #define PLUGIN_API_VERSION_MAJOR 3
 #define PLUGIN_API_VERSION_MINOR 4
-#define PLUGIN_API_VERSION_PATCH 0
+#define PLUGIN_API_VERSION_PATCH 1
 
 //
 // Just some not so smart defines to retrieve plugin api version as string
@@ -51,7 +51,7 @@ extern "C" {
 // give this name to the associated *_ext struct.
 typedef struct
 {
-	ss_plugin_table_fieldinfo* (*list_table_fields)(ss_plugin_table_t* t, uint32_t* nfields);
+	const ss_plugin_table_fieldinfo* (*list_table_fields)(ss_plugin_table_t* t, uint32_t* nfields);
 	ss_plugin_table_field_t* (*get_table_field)(ss_plugin_table_t* t, const char* name, ss_plugin_state_type data_type);
 	ss_plugin_table_field_t* (*add_table_field)(ss_plugin_table_t* t, const char* name, ss_plugin_state_type data_type);
 } ss_plugin_table_fields_vtable;
@@ -66,7 +66,7 @@ typedef struct
 	// available in the entries of the table. nfields will be filled with the number
 	// of elements of the returned array. The array's memory is owned by the
 	// tables's owner. Returns NULL in case of error.
-	ss_plugin_table_fieldinfo* (*list_table_fields)(ss_plugin_table_t* t, uint32_t* nfields);
+	const ss_plugin_table_fieldinfo* (*list_table_fields)(ss_plugin_table_t* t, uint32_t* nfields);
 	//
 	// Returns an opaque pointer representing an accessor to a data field
 	// present in all entries of the table, given its name and type.