Initial revision

lang/occam/lib/ocm_chan.h

@@ -0,0 +1,47 @@
+/*	channel.h - channel definitions */
+#include <stdio.h>
+#include "parco.h"
+
+typedef union channel {
+	struct {		/* Interprocess channel */
+		char _type;	/* Channel type, see note */
+		char synch;	/* State in channel synchronization */
+		long val;	/* Transmitted value */
+	} c;
+	struct {		/* File channel */
+		char _type;	/* Dummy field, see note */
+		char index;	/* Index in the file array */
+		char flgs;	/* Status flags: in use & readahead */
+		char preread;	/* Possible preread character */
+	} f;
+} chan;
+#define type		c._type	/* Channel type */
+/* Note: The channel type should not be part of each structure in chan. But
+ * the C alignment rules would make chan about 50% bigger if we had done it
+ * the right way. Note that the order of fields in a struct cannot be a problem
+ * as long as struct c is the largest within the union.
+ */
+
+#define C_T_CHAN	0	/* Type of a interprocess channel */
+#define C_T_FILE	1	/* Type of a file channel */
+
+#define C_S_FREE	0	/* IP channel is free */
+#define C_S_ANY		1	/* IP channel contains data */
+#define C_S_ACK		2	/* IP channel data is removed */
+
+#define C_F_EOF		(-1L)	/* File channel returns EOF */
+#define C_F_TEXT	(-2L)	/* File channel becomes line oriented */
+#define C_F_RAW		(-3L)	/* File channel becomes character oriented */
+
+#define C_F_INUSE	0x01	/* File channel is connected to a UNIX file */
+#define C_F_READAHEAD	0x02	/* File channel has a preread character */
+
+extern chan file[_NFILE];	/* Array of file channels */
+extern FILE *unix_file[_NFILE];	/* Pointers to buffered UNIX files */
+
+void c_init();
+
+void chan_in(), cbyte_in(), c_wa_in(), c_ba_in();
+void chan_out(), c_wa_out(), c_ba_out();
+
+int chan_any();