ioctl restructuring.

lib/c/labcomm.c

@@ -446,15 +446,23 @@ int labcomm_encoder_ioctl(struct labcomm_encoder *encoder,
                            int action,
                            ...)
 {
-  int result = -ENOTSUP;
-  
-  if (encoder->writer->action->ioctl != NULL) {
-    va_list va;
+  int result;
+  va_list va;
     
-    va_start(va, action);
-    result = encoder->writer->action->ioctl(encoder->writer, action, NULL, va);
-    va_end(va);
+  if (encoder->writer->action->ioctl == NULL) {
+    result = -ENOTSUP;
+    goto out;
+  }
+  if (LABCOMM_IOC_SIG(action) != LABCOMM_IOC_NOSIG) {
+    result = -EINVAL;
+    goto out;
   }
+    
+  va_start(va, action);
+  result = encoder->writer->action->ioctl(encoder->writer, action, NULL, va);
+  va_end(va);
+
+out:
   return result;
 }
 
@@ -462,15 +470,22 @@ static int labcomm_writer_ioctl(struct labcomm_writer *writer,
 				int action,
 				...)
 {
-  int result = -ENOTSUP;
-  
-  if (writer->action->ioctl != NULL) {
-    va_list va;
-    
-    va_start(va, action);
-    result = writer->action->ioctl(writer, action, NULL, va);
-    va_end(va);
+  int result;
+  va_list va;
+
+  if (writer->action->ioctl == NULL) {
+    result = -ENOTSUP;
+    goto out;
+  }
+  if (LABCOMM_IOC_SIG(action) != LABCOMM_IOC_NOSIG) {
+    result = -EINVAL;
+    goto out;
   }
+  
+  va_start(va, action);
+  result = writer->action->ioctl(writer, action, NULL, va);
+  va_end(va);
+out:
   return result;
 }
 

lib/c/labcomm_ioctl.h

+#ifndef __LABCOMM_IOCTL_H__
+#define __LABCOMM_IOCTL_H__
+
 #include "labcomm.h"
 
+/*
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ * | |   |                         |               |               |  
+ * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  | |   |                         |               |
+ *  | |   |                         |               +- number    (8)
+ *  | |   |                         +----------------- type      (8)
+ *  | |   +------------------------------------------- size      (13)
+ *  | +----------------------------------------------- direction (2)
+ *  +------------------------------------------------- signature (1)
+ *  
+ * type 0-31     are reserved for labcomm library use
+ */
+
+
+#define LABCOMM_IOC_NRBITS      8
+#define LABCOMM_IOC_TYPEBITS    8
+#define LABCOMM_IOC_SIZEBITS   13
+#define LABCOMM_IOC_DIRBITS     2
+#define LABCOMM_IOC_SIGBITS     1
+#define LABCOMM_IOC_NRMASK     ((1 << LABCOMM_IOC_NRBITS)-1)
+#define LABCOMM_IOC_TYPEMASK   ((1 << LABCOMM_IOC_TYPEBITS)-1)
+#define LABCOMM_IOC_SIZEMASK   ((1 << LABCOMM_IOC_SIZEBITS)-1)
+#define LABCOMM_IOC_DIRMASK    ((1 << LABCOMM_IOC_DIRBITS)-1)
+#define LABCOMM_IOC_SIGMASK    ((1 << LABCOMM_IOC_SIGBITS)-1)
+#define LABCOMM_IOC_NRSHIFT    0
+#define LABCOMM_IOC_TYPESHIFT  (LABCOMM_IOC_NRSHIFT+LABCOMM_IOC_NRBITS)
+#define LABCOMM_IOC_SIZESHIFT  (LABCOMM_IOC_TYPESHIFT+LABCOMM_IOC_TYPEBITS)
+#define LABCOMM_IOC_DIRSHIFT   (LABCOMM_IOC_SIZESHIFT+LABCOMM_IOC_SIZEBITS)
+#define LABCOMM_IOC_SIGSHIFT   (LABCOMM_IOC_DIRSHIFT+LABCOMM_IOC_DIRBITS)
+
+#define LABCOMM_IOC_NOSIG       0U
+#define LABCOMM_IOC_USESIG      1U
+
+#define LABCOMM_IOC_NONE        0U
+#define LABCOMM_IOC_WRITE       1U
+#define LABCOMM_IOC_READ        2U
+
+#define LABCOMM_IOC(signature,dir,type,nr,size)	  \
+  (((signature) << LABCOMM_IOC_SIGSHIFT) |	  \
+   ((dir)       << LABCOMM_IOC_DIRSHIFT) |	  \
+   ((size)      << LABCOMM_IOC_SIZESHIFT) |	  \
+   ((type)      << LABCOMM_IOC_TYPESHIFT) |	  \
+   ((nr)        << LABCOMM_IOC_NRSHIFT))	  
+
+#define LABCOMM_IOC_SIG(nr) \
+  (((nr) >> LABCOMM_IOC_SIGSHIFT) & LABCOMM_IOC_SIGMASK)
+#define LABCOMM_IOC_DIR(nr) \
+  (((nr) >> LABCOMM_IOC_DIRSHIFT) & LABCOMM_IOC_DIRMASK)
+#define LABCOMM_IOC_SIZE(nr) \
+  (((nr) >> LABCOMM_IOC_SIZESHIFT) & LABCOMM_IOC_SIZEMASK)
+#define LABCOMM_IOC_TYPE(nr) \
+  (((nr) >> LABCOMM_IOC_TYPESHIFT) & LABCOMM_IOC_TYPEMASK)
+#define LABCOMM_IOC_NR(nr) \
+  (((nr) >> LABCOMM_IOC_NRSHIFT) & LABCOMM_IOC_NRMASK)
+
+#define LABCOMM_IO(type,nr)						\
+  LABCOMM_IOC(LABCOMM_IOC_NOSIG,LABCOMM_IOC_NONE,type,nr,0)
+#define LABCOMM_IOR(type,nr,size)					\
+  LABCOMM_IOC(LABCOMM_IOC_NOSIG,LABCOMM_IOC_READ,type,nr,sizeof(size))
+#define LABCOMM_IOW(type,nr,size)					\
+  LABCOMM_IOC(LABCOMM_IOC_NOSIG,LABCOMM_IOC_WRITE,type,nr,sizeof(size))
+#define LABCOMM_IOS(type,nr)					\
+  LABCOMM_IOC(LABCOMM_IOC_USESIG,LABCOMM_IOC_READ,type,nr,0)
+#define LABCOMM_IOSR(type,nr,size)					\
+  LABCOMM_IOC(LABCOMM_IOC_USESIG,LABCOMM_IOC_READ,type,nr,sizeof(size))
+#define LABCOMM_IOSW(type,nr,size)					\
+  LABCOMM_IOC(LABCOMM_IOC_USESIG,LABCOMM_IOC_WRITE,type,nr,sizeof(size))
+
 struct labcomm_ioctl_register_signature {
   int index;
   struct labcomm_signature *signature;
 };
 
-#define LABCOMM_IOCTL_REGISTER_SIGNATURE         0x0001
-#define LABCOMM_IOCTL_WRITER_GET_BYTES_WRITTEN   0x0002
-#define LABCOMM_IOCTL_WRITER_GET_BYTE_POINTER    0x0003
-#define LABCOMM_IOCTL_WRITER_COPY_BYTES          0x0004
+#define LABCOMM_IOCTL_REGISTER_SIGNATURE \
+  LABCOMM_IOW(0,1,struct labcomm_ioctl_register_signature)
+#define LABCOMM_IOCTL_WRITER_GET_BYTES_WRITTEN \
+  LABCOMM_IOR(0,2,int)
+#define LABCOMM_IOCTL_WRITER_GET_BYTE_POINTER \
+  LABCOMM_IOR(0,3,void*)
+
+#endif