[src/trunk]: src/sys/net Clarify two functions.

[maxv <maxv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/39840285599a
branches:  trunk
changeset: 365387:39840285599a
user:      maxv <maxv%NetBSD.org@localhost>
date:      Mon Aug 13 09:29:13 2018 +0000

description:
Clarify two functions.

diffstat:

 sys/net/if_pppoe.c |  59 +++++++++++++++++++++++++++++++----------------------
 1 files changed, 34 insertions(+), 25 deletions(-)

diffs (147 lines):

diff -r ac1ceb9410a0 -r 39840285599a sys/net/if_pppoe.c
--- a/sys/net/if_pppoe.c        Mon Aug 13 09:25:22 2018 +0000
+++ b/sys/net/if_pppoe.c        Mon Aug 13 09:29:13 2018 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: if_pppoe.c,v 1.141 2018/06/26 06:48:02 msaitoh Exp $ */
+/* $NetBSD: if_pppoe.c,v 1.142 2018/08/13 09:29:13 maxv Exp $ */
 
 /*-
  * Copyright (c) 2002, 2008 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_pppoe.c,v 1.141 2018/06/26 06:48:02 msaitoh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_pppoe.c,v 1.142 2018/08/13 09:29:13 maxv Exp $");
 
 #ifdef _KERNEL_OPT
 #include "pppoe.h"
@@ -1329,32 +1329,33 @@
 pppoe_send_padi(struct pppoe_softc *sc)
 {
        struct mbuf *m0;
-       int len, l1 = 0, l2 = 0; /* XXX: gcc */
+       int len, l1 = 0, l2 = 0;
        uint8_t *p;
 
-       if (sc->sc_state >PPPOE_STATE_PADI_SENT)
+       if (sc->sc_state > PPPOE_STATE_PADI_SENT)
                panic("pppoe_send_padi in state %d", sc->sc_state);
 
-       /* calculate length of frame (excluding ethernet header + pppoe header) */
-       len = 2 + 2 + 2 + 2 + sizeof sc;        /* service name tag is required, host unique is send too */
+       /* Compute packet length. */
+       len = sizeof(struct pppoetag);
        if (sc->sc_service_name != NULL) {
                l1 = strlen(sc->sc_service_name);
                len += l1;
        }
        if (sc->sc_concentrator_name != NULL) {
                l2 = strlen(sc->sc_concentrator_name);
-               len += 2 + 2 + l2;
+               len += sizeof(struct pppoetag) + l2;
        }
+       len += sizeof(struct pppoetag) + sizeof(sc);
        if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MAXMTU) {
-               len += 2 + 2 + 2;
+               len += sizeof(struct pppoetag) + 2;
        }
 
-       /* allocate a buffer */
-       m0 = pppoe_get_mbuf(len + PPPOE_HEADERLEN);     /* header len + payload len */
-       if (!m0)
+       /* Allocate packet. */
+       m0 = pppoe_get_mbuf(len + PPPOE_HEADERLEN);
+       if (m0 == NULL)
                return ENOBUFS;
 
-       /* fill in pkt */
+       /* Fill in packet. */
        p = mtod(m0, uint8_t *);
        PPPOE_ADD_HEADER(p, PPPOE_CODE_PADI, 0, len);
        PPPOE_ADD_16(p, PPPOE_TAG_SNAME);
@@ -1373,7 +1374,7 @@
        }
        PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
        PPPOE_ADD_16(p, sizeof(sc));
-       memcpy(p, &sc, sizeof sc);
+       memcpy(p, &sc, sizeof(sc));
        p += sizeof(sc);
 
        if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MAXMTU) {
@@ -1388,7 +1389,7 @@
                    (long)(len + PPPOE_HEADERLEN), (long)(p - mtod(m0, uint8_t *)));
 #endif
 
-       /* send pkt */
+       /* Send packet. */
        return pppoe_output(sc, m0);
 }
 
@@ -1598,32 +1599,39 @@
        sc->sc_state = PPPOE_STATE_INITIAL;
 }
 
-/* Send a PADR packet */
 static int
 pppoe_send_padr(struct pppoe_softc *sc)
 {
        struct mbuf *m0;
        uint8_t *p;
-       size_t len, l1 = 0; /* XXX: gcc */
+       size_t len, l1 = 0;
 
        if (sc->sc_state != PPPOE_STATE_PADR_SENT)
                return EIO;
 
-       len = 2 + 2 + 2 + 2 + sizeof(sc);               /* service name, host unique */
-       if (sc->sc_service_name != NULL) {              /* service name tag maybe empty */
+       /* Compute packet length. */
+       len = sizeof(struct pppoetag);
+       if (sc->sc_service_name != NULL) {
                l1 = strlen(sc->sc_service_name);
                len += l1;
        }
-       if (sc->sc_ac_cookie_len > 0)
-               len += 2 + 2 + sc->sc_ac_cookie_len;    /* AC cookie */
-       if (sc->sc_relay_sid_len > 0)
-               len += 2 + 2 + sc->sc_relay_sid_len;    /* Relay SID */
+       if (sc->sc_ac_cookie_len > 0) {
+               len += sizeof(struct pppoetag) + sc->sc_ac_cookie_len;
+       }
+       if (sc->sc_relay_sid_len > 0) {
+               len += sizeof(struct pppoetag) + sc->sc_relay_sid_len;
+       }
+       len += sizeof(struct pppoetag) + sizeof(sc);
        if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MAXMTU) {
-               len += 2 + 2 + 2;
+               len += sizeof(struct pppoetag) + 2;
        }
+
+       /* Allocate packet. */
        m0 = pppoe_get_mbuf(len + PPPOE_HEADERLEN);
-       if (!m0)
+       if (m0 == NULL)
                return ENOBUFS;
+
+       /* Fill in packet. */
        p = mtod(m0, uint8_t *);
        PPPOE_ADD_HEADER(p, PPPOE_CODE_PADR, 0, len);
        PPPOE_ADD_16(p, PPPOE_TAG_SNAME);
@@ -1648,7 +1656,7 @@
        }
        PPPOE_ADD_16(p, PPPOE_TAG_HUNIQUE);
        PPPOE_ADD_16(p, sizeof(sc));
-       memcpy(p, &sc, sizeof sc);
+       memcpy(p, &sc, sizeof(sc));
        p += sizeof(sc);
 
        if (sc->sc_sppp.pp_if.if_mtu > PPPOE_MAXMTU) {
@@ -1663,6 +1671,7 @@
                        (long)(len + PPPOE_HEADERLEN), (long)(p - mtod(m0, uint8_t *)));
 #endif
 
+       /* Send packet. */
        return pppoe_output(sc, m0);
 }