On synchronous links, typically the following options are set on the command

line: novj noccp noaccomp nopcomp. However, even so, the comp STREAMS module
was always pushed on the stream. This behavior has been changed, such that
when those options are set, the stream will be comp-less. This is not
specific to synchronous cases by the way, as it also applies on async
as well.

diff --git a/pppd/sys-svr4.c b/pppd/sys-svr4.c
index 036eec6c7f78f62b6388a5e79114486becd3746f..0743da189060271b1194ff54726f242d9dc3e1b9 100644 (file)
--- a/pppd/sys-svr4.c
+++ b/pppd/sys-svr4.c
@@ -25,7 +25,7 @@
  * OR MODIFICATIONS.
  */
 
-#define RCSID  "$Id: sys-svr4.c,v 1.40 2000/01/28 01:51:19 masputra Exp $"
+#define RCSID  "$Id: sys-svr4.c,v 1.41 2000/02/11 03:09:19 masputra Exp $"
 
 #include <limits.h>
 #include <stdio.h>
@@ -67,6 +67,10 @@
 #endif
 
 #include "pppd.h"
+#include "fsm.h"
+#include "lcp.h"
+#include "ipcp.h"
+#include "ccp.h"
 
 #if !defined(PPP_DEV_NAME)
 #define PPP_DEV_NAME   "/dev/ppp"
@@ -687,6 +691,27 @@ ppp_available()
     return stat(PPP_DEV_NAME, &buf) >= 0;
 }
 
+/*
+ * any_compressions - see if compression is enabled or not
+ *
+ * In the STREAMS implementation of kernel-portion pppd,
+ * the comp STREAMS module performs the ACFC, PFC, as well
+ * CCP and VJ compressions. However, if the user has explicitly
+ * declare to not enable them from the command line, there is
+ * no point of having the comp module be pushed on the stream.
+ */
+static int
+any_compressions()
+{
+    if ((!lcp_wantoptions[0].neg_accompression) &&
+       (!lcp_wantoptions[0].neg_pcompression) &&
+       (!ccp_protent.enabled_flag) &&
+       (!ipcp_wantoptions[0].neg_vj)) {
+           return 0;
+    }
+    return 1;
+}
+
 /*
  * establish_ppp - Turn the serial port into a ppp interface.
  */
@@ -718,12 +743,21 @@ establish_ppp(fd)
        i = PPPDBG_LOG + PPPDBG_AHDLC;
        strioctl(pppfd, PPPIO_DEBUG, &i, sizeof(int), 0);
     }
-    if (ioctl(fd, I_PUSH, COMP_MOD_NAME) < 0)
-       error("Couldn't push PPP compression module: %m");
-    else
-       ++tty_npushed;
+    /*
+     * There's no need to push comp module if we don't intend
+     * to compress anything
+     */
+    if (any_compressions()) { 
+        if (ioctl(fd, I_PUSH, COMP_MOD_NAME) < 0)
+           error("Couldn't push PPP compression module: %m");
+       else
+           ++tty_npushed;
+    }
+
     if (kdebugflag & 2) {
-       i = PPPDBG_LOG + PPPDBG_COMP;
+       i = PPPDBG_LOG; 
+       if (any_compressions())
+           i += PPPDBG_COMP;
        strioctl(pppfd, PPPIO_DEBUG, &i, sizeof(int), 0);
     }
 
@@ -1294,7 +1328,8 @@ ppp_send_config(unit, mtu, asyncmap, pcomp, accomp)
        }
        cf[0] = (pcomp? COMP_PROT: 0) + (accomp? COMP_AC: 0);
        cf[1] = COMP_PROT | COMP_AC;
-       if (strioctl(pppfd, PPPIO_CFLAGS, cf, sizeof(cf), sizeof(int)) < 0) {
+       if (any_compressions() &&
+           strioctl(pppfd, PPPIO_CFLAGS, cf, sizeof(cf), sizeof(int)) < 0) {
            error("Couldn't set prot/AC compression: %m");
        }
     }
@@ -1367,7 +1402,8 @@ ppp_recv_config(unit, mru, asyncmap, pcomp, accomp)
        }
        cf[0] = (pcomp? DECOMP_PROT: 0) + (accomp? DECOMP_AC: 0);
        cf[1] = DECOMP_PROT | DECOMP_AC;
-       if (strioctl(pppfd, PPPIO_CFLAGS, cf, sizeof(cf), sizeof(int)) < 0) {
+       if (any_compressions() &&
+           strioctl(pppfd, PPPIO_CFLAGS, cf, sizeof(cf), sizeof(int)) < 0) {
            error("Couldn't set prot/AC decompression: %m");
        }
     }