[PATCH 2/4] devPrivates rework (v2): interface

[Eamon Walsh]

Adds dix header privates.h containing new interface.

--

 privates.h |  159 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 159 insertions(+)

--
diff --git a/include/privates.h b/include/privates.h
new file mode 100644
index 0000000..898fdd9
--- /dev/null
+++ b/include/privates.h
@@ -0,0 +1,159 @@
+/***********************************************************
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+******************************************************************/
+
+#ifndef PRIVATES_H
+#define PRIVATES_H 1
+
+#include "dix.h"
+#include "resource.h"
+
+/*****************************************************************
+ * STUFF FOR PRIVATES
+ *****************************************************************/
+
+typedef struct _PrivateKey {
+    int unused;
+} devprivate_key_t;
+
+typedef struct _Private {
+    devprivate_key_t	*key;
+    int			dontfree;
+    pointer		value;
+    struct _Private	*next;
+} PrivateRec;
+
+/*
+ * Request pre-allocated private space for your driver/module.
+ * A non-null pScreen argument restricts to objects on a given screen.
+ */
+extern int
+dixRequestPrivate(RESTYPE type, devprivate_key_t *const key,
+		  unsigned size, pointer pScreen);
+
+/*
+ * Allocates a new private and attaches it to an existing object.
+ */
+extern pointer *
+dixAllocatePrivate(PrivateRec **privates, devprivate_key_t *const key);
+
+/*
+ * Look up a private pointer.
+ */
+static _X_INLINE pointer
+dixLookupPrivate(PrivateRec **privates, devprivate_key_t *const key)
+{
+    PrivateRec *rec = *privates;
+    pointer *ptr;
+
+    while (rec) {
+	if (rec->key == key)
+	    return rec->value;
+	rec = rec->next;
+    }
+
+    ptr = dixAllocatePrivate(privates, key);
+    return ptr ? *ptr : NULL;
+}
+
+/*
+ * Look up the address of a private pointer.
+ */
+static _X_INLINE pointer *
+dixLookupPrivateAddr(PrivateRec **privates, devprivate_key_t *const key)
+{
+    PrivateRec *rec = *privates;
+
+    while (rec) {
+	if (rec->key == key)
+	    return &rec->value;
+	rec = rec->next;
+    }
+
+    return dixAllocatePrivate(privates, key);
+}
+
+/*
+ * Set a private pointer.
+ */
+static _X_INLINE int
+dixSetPrivate(PrivateRec **privates, devprivate_key_t *const key, pointer val)
+{
+    PrivateRec *rec;
+
+ top:
+    rec = *privates;
+    while (rec) {
+	if (rec->key == key) {
+	    rec->value = val;
+	    return TRUE;
+	}
+	rec = rec->next;
+    }
+
+    if (!dixAllocatePrivate(privates, key))
+	return FALSE;
+    goto top;
+}
+
+/*
+ * Register callbacks to be called on private allocation/freeing.
+ * The calldata argument to the callbacks is a PrivateCallbackPtr.
+ */
+typedef struct _PrivateCallback {
+    devprivate_key_t *key;	/* private registration key */
+    pointer value;		/* pointer to private */
+} PrivateCallbackRec;
+
+extern int
+dixRegisterPrivateInitFunc(devprivate_key_t *const key,
+			   CallbackProcPtr callback, pointer userdata);
+
+extern int
+dixRegisterPrivateDeleteFunc(devprivate_key_t *const key,
+			     CallbackProcPtr callback, pointer userdata);
+
+/*
+ * Allocates all pre-requested private space in one chunk.
+ */
+extern PrivateRec *
+dixAllocatePrivates(RESTYPE type, pointer parent);
+
+/*
+ * Frees any private space that is not part of an object.
+ */
+extern void
+dixFreePrivates(PrivateRec *privates);
+
+/*
+ * Resets the subsystem, called from the main loop.
+ */
+extern int
+dixResetPrivates(void);
+
+/*
+ * These next two functions are necessary because the position of
+ * the devPrivates field varies by structure and calling code might
+ * only know the resource type, not the structure definition.
+ */
+
+/*
+ * Looks up the offset where the devPrivates field is located by type.
+ */
+extern unsigned
+dixLookupPrivateOffset(RESTYPE type);
+
+/*
+ * Specifies the offset where the devPrivates field is located.
+ */
+extern int
+dixRegisterPrivateOffset(RESTYPE type, unsigned offset);
+
+#endif /* PRIVATES_H */