[RFC 2/3] modules: Implement module_is_loaded function

[Jose R. Ziviani]

The function module_load_one() fills a hash table will all modules that
were successfuly loaded. However, that table is a static variable of
module_load_one(). This patch changes it and creates a function that
informs whether a given module was loaded or not.

Signed-off-by: Jose R. Ziviani <jziviani@suse.de>
---
 include/qemu/module.h |  3 +++
 util/module.c         | 28 +++++++++++++++++++++-------
 2 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/include/qemu/module.h b/include/qemu/module.h
index 456e190a55..01779cc7fb 100644
--- a/include/qemu/module.h
+++ b/include/qemu/module.h
@@ -14,6 +14,7 @@
 #ifndef QEMU_MODULE_H
 #define QEMU_MODULE_H
 
+#include <stdbool.h>
 
 #define DSO_STAMP_FUN         glue(qemu_stamp, CONFIG_STAMP)
 #define DSO_STAMP_FUN_STR     stringify(DSO_STAMP_FUN)
@@ -74,6 +75,8 @@ void module_load_qom_one(const char *type);
 void module_load_qom_all(void);
 void module_allow_arch(const char *arch);
 
+bool module_is_loaded(const char *name);
+
 /**
  * DOC: module info annotation macros
  *
diff --git a/util/module.c b/util/module.c
index 6bb4ad915a..64307b7a25 100644
--- a/util/module.c
+++ b/util/module.c
@@ -119,6 +119,8 @@ static const QemuModinfo module_info_stub[] = { {
 static const QemuModinfo *module_info = module_info_stub;
 static const char *module_arch;
 
+static GHashTable *loaded_modules;
+
 void module_init_info(const QemuModinfo *info)
 {
     module_info = info;
@@ -206,13 +208,10 @@ static int module_load_file(const char *fname, bool 
mayfail, bool export_symbols
 out:
     return ret;
 }
-#endif
 
 bool module_load_one(const char *prefix, const char *lib_name, bool mayfail)
 {
     bool success = false;
-
-#ifdef CONFIG_MODULES
     char *fname = NULL;
 #ifdef CONFIG_MODULE_UPGRADES
     char *version_dir;
@@ -223,7 +222,6 @@ bool module_load_one(const char *prefix, const char 
*lib_name, bool mayfail)
     int i = 0, n_dirs = 0;
     int ret;
     bool export_symbols = false;
-    static GHashTable *loaded_modules;
     const QemuModinfo *modinfo;
     const char **sl;
 
@@ -307,12 +305,9 @@ bool module_load_one(const char *prefix, const char 
*lib_name, bool mayfail)
         g_free(dirs[i]);
     }
 
-#endif
     return success;
 }
 
-#ifdef CONFIG_MODULES
-
 static bool module_loaded_qom_all;
 
 void module_load_qom_one(const char *type)
@@ -377,6 +372,15 @@ void qemu_load_module_for_opts(const char *group)
     }
 }
 
+bool module_is_loaded(const char *name)
+{
+    if (!loaded_modules || !g_hash_table_contains(loaded_modules, name)) {
+        return false;
+    }
+
+    return true;
+}
+
 #else
 
 void module_allow_arch(const char *arch) {}
@@ -384,4 +388,14 @@ void qemu_load_module_for_opts(const char *group) {}
 void module_load_qom_one(const char *type) {}
 void module_load_qom_all(void) {}
 
+bool module_load_one(const char *prefix, const char *lib_name, bool mayfail)
+{
+    return false;
+}
+
+bool module_is_loaded(const char *name)
+{
+    return false;
+}
+
 #endif
-- 
2.32.0