Add 'resource' keeper.

Signed-off-by: Florent Bruneau <florent.bruneau@polytechnique.org>

diff --git a/postlicyd/resources.c b/postlicyd/resources.c
new file mode 100644 (file)
index 0000000..759c717
--- /dev/null
+++ b/postlicyd/resources.c
@@ -0,0 +1,141 @@
+/******************************************************************************/
+/*          pfixtools: a collection of postfix related tools                  */
+/*          ~~~~~~~~~                                                         */
+/*  ________________________________________________________________________  */
+/*                                                                            */
+/*  Redistribution and use in source and binary forms, with or without        */
+/*  modification, are permitted provided that the following conditions        */
+/*  are met:                                                                  */
+/*                                                                            */
+/*  1. Redistributions of source code must retain the above copyright         */
+/*     notice, this list of conditions and the following disclaimer.          */
+/*  2. Redistributions in binary form must reproduce the above copyright      */
+/*     notice, this list of conditions and the following disclaimer in the    */
+/*     documentation and/or other materials provided with the distribution.   */
+/*  3. The names of its contributors may not be used to endorse or promote    */
+/*     products derived from this software without specific prior written     */
+/*     permission.                                                            */
+/*                                                                            */
+/*  THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND   */
+/*  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE     */
+/*  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR        */
+/*  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS    */
+/*  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR    */
+/*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF      */
+/*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  */
+/*  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN   */
+/*  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)   */
+/*  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF    */
+/*  THE POSSIBILITY OF SUCH DAMAGE.                                           */
+/******************************************************************************/
+
+/*
+ * Copyright © 2008 Florent Bruneau
+ */
+
+#include "str.h"
+#include "array.h"
+#include "resources.h"
+
+typedef struct resource_t {
+    char *key;
+    void *data;
+    int  refcount;
+    resource_destructor_t destructor;
+} resource_t;
+ARRAY(resource_t);
+
+#define RESOURCE_INIT { NULL, NULL, 0, NULL }
+
+static A(resource_t) resources = ARRAY_INIT;
+
+#define RESOURCE_KEY                                                           \
+    char rskey[BUFSIZ];                                                        \
+    m_strcpy(rskey, BUFSIZ, ns);                                               \
+    m_strcat(rskey, BUFSIZ, "@@");                                             \
+    m_strcat(rskey, BUFSIZ, key);
+
+static inline void resource_wipe(resource_t *res)
+{
+    static const resource_t vr = RESOURCE_INIT;
+    if (res->destructor) {
+        res->destructor(res->data);
+    }
+    p_delete(&res->key);
+    *res = vr;
+}
+
+static inline resource_t *resource_find(const char *key, bool create)
+{
+    foreach (resource_t* res, resources) {
+        if (strcmp(res->key, key) == 0) {
+            return res;
+        }
+    }}
+    if (create) {
+        resource_t res = RESOURCE_INIT;
+        res.key = m_strdup(key);
+        array_add(resources, res);
+        return &array_last(resources);
+    }
+    return NULL;
+}
+
+void *resource_get(const char *ns, const char *key)
+{
+    RESOURCE_KEY;
+    resource_t *entry = resource_find(rskey, false);
+    if (entry == NULL) {
+        return NULL;
+    } else {
+        ++entry->refcount;
+        return entry->data;
+    }
+}
+
+bool resource_set(const char *ns, const char *key, void *data,
+                  resource_destructor_t destructor) {
+    RESOURCE_KEY;
+    resource_t *entry = resource_find(rskey, true);
+    if (entry->data != NULL) {
+        if (entry->destructor) {
+            entry->destructor(entry->data);
+        }
+    }
+    entry->refcount  += 1;
+    entry->data       = data;
+    entry->destructor = destructor;
+    return true;
+}
+
+void resource_release(const char *ns, const char *key)
+{
+    RESOURCE_KEY;
+    resource_t *entry = resource_find(rskey, false);
+    if (entry != NULL) {
+        assert(entry->refcount > 0);
+        --entry->refcount;
+    }
+}
+
+void resource_garbage_collect(void)
+{
+    uint32_t used = 0;
+    foreach (resource_t *res, resources) {
+        if (res->key != NULL && res->refcount == 0) {
+            resource_wipe(res);
+        } else if (res->key != NULL) {
+            if (used < __Ai) {
+                array_elt(resources, used) = *res;
+            }
+            ++used;
+        }
+    }}
+    array_len(resources) = used;
+}
+
+static void resources_exit(void)
+{
+    array_deep_wipe(resources, resource_wipe);
+}
+module_exit(resources_exit);

diff --git a/postlicyd/resources.h b/postlicyd/resources.h
new file mode 100644 (file)
index 0000000..973a608
--- /dev/null
+++ b/postlicyd/resources.h
@@ -0,0 +1,55 @@
+/******************************************************************************/
+/*          pfixtools: a collection of postfix related tools                  */
+/*          ~~~~~~~~~                                                         */
+/*  ________________________________________________________________________  */
+/*                                                                            */
+/*  Redistribution and use in source and binary forms, with or without        */
+/*  modification, are permitted provided that the following conditions        */
+/*  are met:                                                                  */
+/*                                                                            */
+/*  1. Redistributions of source code must retain the above copyright         */
+/*     notice, this list of conditions and the following disclaimer.          */
+/*  2. Redistributions in binary form must reproduce the above copyright      */
+/*     notice, this list of conditions and the following disclaimer in the    */
+/*     documentation and/or other materials provided with the distribution.   */
+/*  3. The names of its contributors may not be used to endorse or promote    */
+/*     products derived from this software without specific prior written     */
+/*     permission.                                                            */
+/*                                                                            */
+/*  THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND   */
+/*  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE     */
+/*  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR        */
+/*  PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS    */
+/*  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR    */
+/*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF      */
+/*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  */
+/*  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN   */
+/*  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)   */
+/*  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF    */
+/*  THE POSSIBILITY OF SUCH DAMAGE.                                           */
+/******************************************************************************/
+
+/*
+ * Copyright © 2008 Florent Bruneau
+ */
+
+#ifndef PFIXTOOLS_RESOURCES_H
+#define PFIXTOOLS_RESOURCES_H
+
+#include "common.h"
+
+typedef void (*resource_destructor_t)(void *);
+
+__attribute__((nonnull(2)))
+void *resource_get(const char *ns, const char *key);
+
+__attribute__((nonnull(2,3)))
+bool resource_set(const char *ns, const char *key, void *data,
+                  resource_destructor_t destructor);
+
+__attribute__((nonnull(1)))
+void resource_release(const char *ns, const char *key);
+
+void resource_garbage_collect(void);
+
+#endif