Added full RT-Linux POSIX interface to LinCAN driver, needs preparation of RT tests.

[lincan.git] / lincan / src / read_rtl.c

diff --git a/lincan/src/read_rtl.c b/lincan/src/read_rtl.c
new file mode 100644 (file)
index 0000000..807f572
--- /dev/null
+++ b/lincan/src/read_rtl.c
@@ -0,0 +1,93 @@
+/* read.c
+ * Linux CAN-bus device driver.
+ * Written by Arnaud Westenberg email:arnaud@wanadoo.nl
+ * Rewritten for new CAN queues by Pavel Pisa - OCERA team member
+ * email:pisa@cmp.felk.cvut.cz
+ * This software is released under the GPL-License.
+ * Version lincan-0.2  9 Jul 2003
+ */
+
+#ifdef CAN_WITH_RTL
+
+#include "../include/can.h"
+#include "../include/can_sysdep.h"
+#include "../include/main.h"
+
+#include <rtl_posixio.h>
+#include "../include/can_iortl.h"
+
+/* This is the 'Normal' read handler for normal transmission messages */
+static inline 
+ssize_t can_std_read_rtl(struct canque_ends_t *qends, int nonblock_fl, 
+                       char *buffer, size_t length)
+{
+       int ret;
+       struct canmsg_t *msg_buff = (struct canmsg_t *)buffer;
+       int bytes_to_copy;
+       struct canque_edge_t *qedge;
+       struct canque_slot_t *slot;
+       
+       ret=canque_test_outslot(qends, &qedge, &slot);
+       if(ret<0){
+               if (nonblock_fl) {
+                       return -EAGAIN;
+               }
+               ret=canque_get_outslot_wait_rtl(qends, &qedge, &slot);
+               if(ret<0){
+                       if (ret==-1) {
+                               DEBUGMSG("Rx interrupted\n");
+                               return -EINTR;
+                       }
+
+                       return -EIO;
+               }
+       }
+       *(msg_buff++)=slot->msg;
+       canque_free_outslot(qends, qedge, slot);
+       bytes_to_copy = length-sizeof(struct canmsg_t);
+       
+       while (bytes_to_copy > 0) {
+               ret=canque_test_outslot(qends, &qedge, &slot);
+               if(ret<0)
+                       break;
+               *(msg_buff++)=slot->msg;
+               canque_free_outslot(qends, qedge, slot);
+               bytes_to_copy -= sizeof(struct canmsg_t);
+       }
+
+       return length-bytes_to_copy;
+}
+
+
+ssize_t can_read_rtl_posix(struct rtl_file *fptr, char *buffer,
+                               size_t length, loff_t *ppos)
+{
+       struct canuser_t *canuser = 
+               (struct canuser_t *)can_get_rtl_file_private_data(fptr);
+       struct canque_ends_t *qends;
+       int      ret;
+
+       if(!canuser || (canuser->magic != CAN_USER_MAGIC)){
+               CANMSG("can_read_rtl_posix: bad canuser magic\n");
+               return -ENODEV;
+       }
+
+       if (length < sizeof(struct canmsg_t)) {
+               DEBUGMSG("Trying to read less bytes than a CAN message, \n");
+               DEBUGMSG("this will always return zero.\n");
+               return 0;
+       }
+
+       qends = canuser->qends;
+
+       /*if (((struct canmsg_t *)buffer)->flags & MSG_RTR)
+               ret = can_rtr_read(chip, obj, buffer);
+       else*/
+               ret = can_std_read_rtl(qends, fptr->f_flags & O_NONBLOCK,
+                       buffer, length);
+
+       return ret;
+}
+
+#endif /*CAN_WITH_RTL*/
+