core: added lt_dlinit(), lt_dlexit() [global reference-counting].

4 files changed, 46 insertions, 0 deletions

diff --git a/include/sltdl/sltdl.h b/include/sltdl/sltdl.h
index f2898e0..ea72338 100644
--- a/include/sltdl/sltdl.h
+++ b/include/sltdl/sltdl.h
@@ -22,6 +22,10 @@ extern "C" {
 
 typedef struct lt_modctx * lt_dlhandle;
 
+/* global reference-counting */
+lt_api int lt_dlinit(void);
+lt_api int lt_dlexit(void);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/project/common.mk b/project/common.mk
index 4b72987..0c11081 100644
--- a/project/common.mk
+++ b/project/common.mk
@@ -1,4 +1,5 @@
 API_SRCS = \
+	src/core/lt_core.c \
 
 INTERNAL_SRCS = \
 
diff --git a/project/tree.mk b/project/tree.mk
index 20f0861..aa7580b 100644
--- a/project/tree.mk
+++ b/project/tree.mk
@@ -1,3 +1,4 @@
 tree.tag:
 		mkdir -p src
+		mkdir -p src/core
 		touch tree.tag
diff --git a/src/core/lt_core.c b/src/core/lt_core.c
new file mode 100644
index 0000000..b0c3952
--- /dev/null
+++ b/src/core/lt_core.c
@@ -0,0 +1,40 @@
+/*******************************************************************/
+/*  sltdl: a surrogate ltdl implementation                         */
+/*  Copyright (C) 2019 Z. Gilboa                                   */
+/*  Released under the Standard MIT License; see COPYING.SLTDL.    */
+/*******************************************************************/
+
+#include <limits.h>
+#include <pthread.h>
+#include <sltdl/sltdl.h>
+
+static int             lt_refs = 0;
+static pthread_mutex_t lt_lock = PTHREAD_MUTEX_INITIALIZER;
+
+int lt_dlinit(void)
+{
+	if (pthread_mutex_lock(&lt_lock))
+		return 1;
+
+	lt_refs++;
+	pthread_mutex_unlock(&lt_lock);
+
+	return 0;
+}
+
+int lt_dlexit(void)
+{
+	if (pthread_mutex_lock(&lt_lock))
+		return 1;
+
+	if (!lt_refs) {
+		pthread_mutex_unlock(&lt_lock);
+		return 1;
+	}
+
+	lt_refs--;
+
+	pthread_mutex_unlock(&lt_lock);
+
+	return 0;
+}