Initial revision

1 files changed, 108 insertions, 0 deletions

diff --git a/zwgc/port.h b/zwgc/port.h
new file mode 100644
index 0000000..886f573
--- /dev/null
+++ b/zwgc/port.h
@@ -0,0 +1,108 @@
+#ifndef port_TYPE
+#define port_TYPE
+
+#include <stdio.h>
+#include "new_string.h"
+#include "string_stack.h"
+
+union port__data {
+    struct {
+	FILE *input_connector;
+	FILE *output_connector;
+    } file;
+    struct {
+	string_stack waiting_packets;
+	string (*filter)();
+    } filter;
+    struct {
+	char *(*output)();
+    } output;
+};
+
+typedef struct {                /* PRIVATE */
+    char *(*get)();
+    char *(*put)();
+    char *(*close_input)();
+    char *(*close_output)();
+#define  INPUT_CLOSED   0x1
+#define  OUTPUT_CLOSED  0x2
+#define  PORT_CLOSED    0x3
+    int status;
+    union port__data data;
+} port;
+
+/*
+ *    void init_ports()
+ *        Modifies: all ports
+ *        Effects: Closes all existing ports.  Must be called before
+ *                 any other port call is made.
+ */
+
+extern void init_ports();
+
+/*
+ *    string read_from_port(string name)
+ *        Requires: init_ports has been called
+ *        Modifies: the port named name if any, $error
+ *        Effects: If a port by name name does not exist, sets $error to
+ *                 "No such port" & returns "".  Otherwise, attempts to
+ *                 read from that port.  If an error occurs, $error is
+ *                 set to the error message and "" returned.  Otherwise
+ *                 the read string is returned.  The returned string is
+ *                 on the heap & must be eventually freed.
+ */
+
+extern string read_from_port();
+
+/*
+ *    void write_on_port(string name, char *text, int length)
+ *        Requires: init_ports has been called, length>=0
+ *        Modifies: the port named name if any, $error
+ *        Effects: If a port by name name does not exist, sets $error to
+ *                 "No such port" & returns.  Otherwise, attempts to
+ *                 write text[0..length-1] on that port.  If an error
+ *                 occurs, $error is set to the error message.
+ */
+
+extern void write_on_port();
+
+/*
+ *    void close_port_input(string name)
+ *        Requires: init_ports has been called
+ *        Modifies: the port named name if any, $error
+ *        Effects: If a port by name name does not exist, sets $error to
+ *                 "No such port" & returns.  Otherwise, closes the
+ *                 input part of the port by name name.  When both a
+ *                 port's input & output parts have been closed, the
+ *                 port is deleted to save space.  If an error
+ *                 occurs, $error is set to the error message.
+ */
+
+extern void close_port_input();
+
+/*
+ *    void close_port_output(string name)
+ *        Requires: init_ports has been called
+ *        Modifies: the port named name if any, $error
+ *        Effects: If a port by name name does not exist, sets $error to
+ *                 "No such port" & returns.  Otherwise, closes the
+ *                 output part of the port by name name.  When both a
+ *                 port's input & output parts have been closed, the
+ *                 port is deleted to save space.  If an error
+ *                 occurs, $error is set to the error message.
+ */
+
+extern void close_port_output();
+
+
+extern void create_subprocess_port();
+extern void create_file_append_port();
+extern void create_file_input_port();
+extern void create_file_output_port();
+extern void create_port_from_filter();
+extern void create_port_from_output_proc();
+
+extern void init_standard_ports();
+extern void create_port_from_files();
+
+#endif