break out special local mail processing (e.g., mapping to the

[unix-history] / usr / src / usr.bin / telnet / ring.c

diff --git a/usr/src/usr.bin/telnet/ring.c b/usr/src/usr.bin/telnet/ring.c
index a738708..cf076db 100644 (file)
--- a/usr/src/usr.bin/telnet/ring.c
+++ b/usr/src/usr.bin/telnet/ring.c
@@ -1,3 +1,14 @@
+/*
+ * Copyright (c) 1988, 1993
+ *     The Regents of the University of California.  All rights reserved.
+ *
+ * %sccs.include.redist.c%
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)ring.c     8.1 (Berkeley) %G%";
+#endif /* not lint */
+

 /*
  * This defines a structure for a ring buffer.
  *
 /*
  * This defines a structure for a ring buffer.
  *


@@ -17,7 +28,9 @@
 #endif
 
 #include       <sys/types.h>
 #endif
 
 #include       <sys/types.h>

+#ifndef        FILIO_H

 #include       <sys/ioctl.h>
 #include       <sys/ioctl.h>

+#endif

 #include       <sys/socket.h>
 
 #include       "ring.h"
 #include       <sys/socket.h>
 
 #include       "ring.h"


@@ -29,12 +42,15 @@
 #define        MIN(a,b)        (((a)<(b))? (a):(b))
 #endif /* !defined(MIN) */
 
 #define        MIN(a,b)        (((a)<(b))? (a):(b))
 #endif /* !defined(MIN) */
 

-#define        ring_subtract(d,a,b)    ((((int)(a))-((int)(b)) >= 0)? \
+#define        ring_subtract(d,a,b)    (((a)-(b) >= 0)? \

                                        (a)-(b): (((a)-(b))+(d)->size))
 
 #define        ring_increment(d,a,c)   (((a)+(c) < (d)->top)? \
                                        (a)+(c) : (((a)+(c))-(d)->size))
 
                                        (a)-(b): (((a)-(b))+(d)->size))
 
 #define        ring_increment(d,a,c)   (((a)+(c) < (d)->top)? \
                                        (a)+(c) : (((a)+(c))-(d)->size))
 

+#define        ring_decrement(d,a,c)   (((a)-(c) >= (d)->bottom)? \
+                                       (a)-(c) : (((a)-(c))-(d)->size))
+

 
 /*
  * The following is a clock, used to determine full, empty, etc.
 
 /*
  * The following is a clock, used to determine full, empty, etc.


@@ -57,10 +73,10 @@ static u_long ring_clock = 0;
 
 /* Buffer state transition routines */
 
 
 /* Buffer state transition routines */
 

-ring_init(ring, buffer, count)
+    ring_init(ring, buffer, count)

 Ring *ring;
 Ring *ring;

-char *buffer;
-int count;
+    unsigned char *buffer;
+    int count;

 {
     memset((char *)ring, 0, sizeof *ring);
 
 {
     memset((char *)ring, 0, sizeof *ring);
 


@@ -70,16 +86,59 @@ int count;
 
     ring->top = ring->bottom+ring->size;
 
 
     ring->top = ring->bottom+ring->size;
 

+#ifdef ENCRYPTION
+    ring->clearto = 0;
+#endif /* ENCRYPTION */
+

     return 1;
 }
 
     return 1;
 }
 

+/* Mark routines */
+
+/*
+ * Mark the most recently supplied byte.
+ */
+
+    void
+ring_mark(ring)
+    Ring *ring;
+{
+    ring->mark = ring_decrement(ring, ring->supply, 1);
+}
+
+/*
+ * Is the ring pointing to the mark?
+ */
+
+    int
+ring_at_mark(ring)
+    Ring *ring;
+{
+    if (ring->mark == ring->consume) {
+       return 1;
+    } else {
+       return 0;
+    }
+}
+
+/*
+ * Clear any mark set on the ring.
+ */
+
+    void
+ring_clear_mark(ring)
+    Ring *ring;
+{
+    ring->mark = 0;
+}
+

 /*
  * Add characters from current segment to ring buffer.
  */
 /*
  * Add characters from current segment to ring buffer.
  */

-void
+    void

 ring_supplied(ring, count)
 ring_supplied(ring, count)

-Ring *ring;
-int count;
+    Ring *ring;
+    int count;

 {
     ring->supply = ring_increment(ring, ring->supply, count);
     ring->supplytime = ++ring_clock;
 {
     ring->supply = ring_increment(ring, ring->supply, count);
     ring->supplytime = ++ring_clock;


@@ -88,11 +147,27 @@ int count;
 /*
  * We have just consumed "c" bytes.
  */
 /*
  * We have just consumed "c" bytes.
  */

-void
+    void

 ring_consumed(ring, count)
 ring_consumed(ring, count)

-Ring *ring;
-int count;
+    Ring *ring;
+    int count;

 {
 {

+    if (count == 0)    /* don't update anything */
+       return;
+
+    if (ring->mark &&
+               (ring_subtract(ring, ring->mark, ring->consume) < count)) {
+       ring->mark = 0;
+    }
+#ifdef ENCRYPTION
+    if (ring->consume < ring->clearto &&
+               ring->clearto <= ring->consume + count)
+       ring->clearto = 0;
+    else if (ring->consume + count > ring->top &&
+               ring->bottom <= ring->clearto &&
+               ring->bottom + ((ring->consume + count) - ring->top))
+       ring->clearto = 0;
+#endif /* ENCRYPTION */

     ring->consume = ring_increment(ring, ring->consume, count);
     ring->consumetime = ++ring_clock;
     /*
     ring->consume = ring_increment(ring, ring->consume, count);
     ring->consumetime = ++ring_clock;
     /*


@@ -109,9 +184,9 @@ int count;
 
 
 /* Number of bytes that may be supplied */
 
 
 /* Number of bytes that may be supplied */

-int
+    int

 ring_empty_count(ring)
 ring_empty_count(ring)

-Ring *ring;
+    Ring *ring;

 {
     if (ring_empty(ring)) {    /* if empty */
            return ring->size;
 {
     if (ring_empty(ring)) {    /* if empty */
            return ring->size;


@@ -121,9 +196,9 @@ Ring *ring;
 }
 
 /* number of CONSECUTIVE bytes that may be supplied */
 }
 
 /* number of CONSECUTIVE bytes that may be supplied */

-int
+    int

 ring_empty_consecutive(ring)
 ring_empty_consecutive(ring)

-Ring *ring;
+    Ring *ring;

 {
     if ((ring->consume < ring->supply) || ring_empty(ring)) {
                            /*
 {
     if ((ring->consume < ring->supply) || ring_empty(ring)) {
                            /*


@@ -139,38 +214,56 @@ Ring *ring;
     }
 }
 
     }
 }
 

-/* number of bytes that are available for consuming */
-int
+/* Return the number of bytes that are available for consuming
+ * (but don't give more than enough to get to cross over set mark)
+ */
+
+    int

 ring_full_count(ring)
 ring_full_count(ring)

-Ring *ring;
+    Ring *ring;

 {
 {

-    if (ring_full(ring)) {
-       return ring->size;      /* nothing consumed, but full */
+    if ((ring->mark == 0) || (ring->mark == ring->consume)) {
+       if (ring_full(ring)) {
+           return ring->size;  /* nothing consumed, but full */
+       } else {
+           return ring_subtract(ring, ring->supply, ring->consume);
+       }

     } else {
     } else {

-       return ring_subtract(ring, ring->supply, ring->consume);
+       return ring_subtract(ring, ring->mark, ring->consume);

     }
 }
 
     }
 }
 

-/* number of CONSECUTIVE bytes available for consuming */
-int
+/*
+ * Return the number of CONSECUTIVE bytes available for consuming.
+ * However, don't return more than enough to cross over set mark.
+ */
+    int

 ring_full_consecutive(ring)
 ring_full_consecutive(ring)

-Ring *ring;
+    Ring *ring;

 {
 {

-    if ((ring->supply < ring->consume) || ring_full(ring)) {
-       return ring_subtract(ring, ring->top, ring->consume);
+    if ((ring->mark == 0) || (ring->mark == ring->consume)) {
+       if ((ring->supply < ring->consume) || ring_full(ring)) {
+           return ring_subtract(ring, ring->top, ring->consume);
+       } else {
+           return ring_subtract(ring, ring->supply, ring->consume);
+       }

     } else {
     } else {

-       return ring_subtract(ring, ring->supply, ring->consume);
+       if (ring->mark < ring->consume) {
+           return ring_subtract(ring, ring->top, ring->consume);
+       } else {        /* Else, distance to mark */
+           return ring_subtract(ring, ring->mark, ring->consume);
+       }

     }
 }
 
 /*
  * Move data into the "supply" portion of of the ring buffer.
  */
     }
 }
 
 /*
  * Move data into the "supply" portion of of the ring buffer.
  */

-void
+    void

 ring_supply_data(ring, buffer, count)
 ring_supply_data(ring, buffer, count)

-Ring *ring;
-char *buffer;
-int count;
+    Ring *ring;
+    unsigned char *buffer;
+    int count;

 {
     int i;
 
 {
     int i;
 


@@ -183,15 +276,16 @@ int count;
     }
 }
 
     }
 }
 

+#ifdef notdef

 
 /*
  * Move data from the "consume" portion of the ring buffer
  */
 
 /*
  * Move data from the "consume" portion of the ring buffer
  */

-void
+    void

 ring_consume_data(ring, buffer, count)
 ring_consume_data(ring, buffer, count)

-Ring *ring;
-char *buffer;
-int count;
+    Ring *ring;
+    unsigned char *buffer;
+    int count;

 {
     int i;
 
 {
     int i;
 


@@ -203,25 +297,40 @@ int count;
        buffer += i;
     }
 }
        buffer += i;
     }
 }

+#endif

 
 

-/* Mark routines */
-
-/* XXX do something here */
-void
-ring_mark(ring)
-Ring *ring;
+#ifdef ENCRYPTION
+    void
+ring_encrypt(ring, encryptor)
+    Ring *ring;
+    void (*encryptor)();

 {
 {

-}
+    unsigned char *s, *c;

 
 

-int
-ring_at_mark(ring)
-Ring *ring;
-{
-    return 0;
+    if (ring_empty(ring) || ring->clearto == ring->supply)
+       return;
+
+    if (!(c = ring->clearto))
+       c = ring->consume;
+
+    s = ring->supply;
+
+    if (s <= c) {
+       (*encryptor)(c, ring->top - c);
+       (*encryptor)(ring->bottom, s - ring->bottom);
+    } else
+       (*encryptor)(c, s - c);
+
+    ring->clearto = ring->supply;

 }
 
 }
 

-void
-ring_clear_mark(ring)
-Ring *ring;
+    void
+ring_clearto(ring)
+    Ring *ring;

 {
 {

+    if (!ring_empty(ring))
+       ring->clearto = ring->supply;
+    else
+       ring->clearto = 0;

 }
 }

+#endif /* ENCRYPTION */