C++ DEBUG_CALL函数代码示例

/*
 * Send NDP Router Advertisement
 */
void ndp_send_ra(Slirp *slirp)
{
    DEBUG_CALL("ndp_send_ra");

    /* Build IPv6 packet */
    struct mbuf *t = m_get(slirp);
    struct ip6 *rip = mtod(t, struct ip6 *);
    rip->ip_src = (struct in6_addr)LINKLOCAL_ADDR;
    rip->ip_dst = (struct in6_addr)ALLNODES_MULTICAST;
    rip->ip_nh = IPPROTO_ICMPV6;
    rip->ip_pl = htons(ICMP6_NDP_RA_MINLEN
                        + NDPOPT_LINKLAYER_LEN
                        + NDPOPT_PREFIXINFO_LEN);
    t->m_len = sizeof(struct ip6) + ntohs(rip->ip_pl);

    /* Build ICMPv6 packet */
    t->m_data += sizeof(struct ip6);
    struct icmp6 *ricmp = mtod(t, struct icmp6 *);
    ricmp->icmp6_type = ICMP6_NDP_RA;
    ricmp->icmp6_code = 0;
    ricmp->icmp6_cksum = 0;

    /* NDP */
    ricmp->icmp6_nra.chl = NDP_AdvCurHopLimit;
    ricmp->icmp6_nra.M = NDP_AdvManagedFlag;
    ricmp->icmp6_nra.O = NDP_AdvOtherConfigFlag;
    ricmp->icmp6_nra.reserved = 0;
    ricmp->icmp6_nra.lifetime = htons(NDP_AdvDefaultLifetime);
    ricmp->icmp6_nra.reach_time = htonl(NDP_AdvReachableTime);
    ricmp->icmp6_nra.retrans_time = htonl(NDP_AdvRetransTime);

    /* Source link-layer address (NDP option) */
    t->m_data += ICMP6_NDP_RA_MINLEN;
    struct ndpopt *opt = mtod(t, struct ndpopt *);
    opt->ndpopt_type = NDPOPT_LINKLAYER_SOURCE;
    opt->ndpopt_len = NDPOPT_LINKLAYER_LEN / 8;
    in6_compute_ethaddr(rip->ip_src, opt->ndpopt_linklayer);

    /* Prefix information (NDP option) */
    t->m_data += NDPOPT_LINKLAYER_LEN;
    struct ndpopt *opt2 = mtod(t, struct ndpopt *);
    opt2->ndpopt_type = NDPOPT_PREFIX_INFO;
    opt2->ndpopt_len = NDPOPT_PREFIXINFO_LEN / 8;
    opt2->ndpopt_prefixinfo.prefix_length = slirp->vprefix_len;
    opt2->ndpopt_prefixinfo.L = 1;
    opt2->ndpopt_prefixinfo.A = 1;
    opt2->ndpopt_prefixinfo.reserved1 = 0;
    opt2->ndpopt_prefixinfo.valid_lt = htonl(NDP_AdvValidLifetime);
    opt2->ndpopt_prefixinfo.pref_lt = htonl(NDP_AdvPrefLifetime);
    opt2->ndpopt_prefixinfo.reserved2 = 0;
    opt2->ndpopt_prefixinfo.prefix = slirp->vprefix_addr6;

    /* ICMPv6 Checksum */
    t->m_data -= NDPOPT_LINKLAYER_LEN;
    t->m_data -= ICMP6_NDP_RA_MINLEN;
    t->m_data -= sizeof(struct ip6);
    ricmp->icmp6_cksum = ip6_cksum(t);

    ip6_output(NULL, t, 0);
}

/*
 * Get urgent data
 *
 * When the socket is created, we set it SO_OOBINLINE,
 * so when OOB data arrives, we soread() it and everything
 * in the send buffer is sent as urgent data
 */
int
sorecvoob(struct socket *so)
{
	struct tcpcb *tp = sototcpcb(so);
	int ret;

	DEBUG_CALL("sorecvoob");
	DEBUG_ARG("so = %p", so);

	/*
	 * We take a guess at how much urgent data has arrived.
	 * In most situations, when urgent data arrives, the next
	 * read() should get all the urgent data.  This guess will
	 * be wrong however if more data arrives just after the
	 * urgent data, or the read() doesn't return all the
	 * urgent data.
	 */
	ret = soread(so);
	if (ret > 0) {
	    tp->snd_up = tp->snd_una + so->so_snd.sb_cc;
	    tp->t_force = 1;
	    tcp_output(tp);
	    tp->t_force = 0;
	}

	return ret;
}

static int
mount_local_read (const char *path, char *buf, size_t size, off_t offset,
                  struct fuse_file_info *fi)
{
  char *r;
  size_t rsize;
  const size_t limit = 2 * 1024 * 1024;
  DECL_G ();
  DEBUG_CALL ("%s, %p, %zu, %ld", path, buf, size, (long) offset);

  /* The guestfs protocol limits size to somewhere over 2MB.  We just
   * reduce the requested size here accordingly and push the problem
   * up to every user.  http://www.jwz.org/doc/worse-is-better.html
   */
  if (size > limit)
    size = limit;

  r = guestfs_pread (g, path, size, offset, &rsize);
  if (r == NULL)
    RETURN_ERRNO;

  /* This should never happen, but at least it stops us overflowing
   * the output buffer if it does happen.
   */
  if (rsize > size)
    rsize = size;

  memcpy (buf, r, rsize);
  free (r);

  return rsize;
}

static int
mount_local_statfs (const char *path, struct statvfs *stbuf)
{
  CLEANUP_FREE_STATVFS struct guestfs_statvfs *r;
  DECL_G ();
  DEBUG_CALL ("%s, %p", path, stbuf);

  r = guestfs_statvfs (g, path);
  if (r == NULL)
    RETURN_ERRNO;

  stbuf->f_bsize = r->bsize;
  stbuf->f_frsize = r->frsize;
  stbuf->f_blocks = r->blocks;
  stbuf->f_bfree = r->bfree;
  stbuf->f_bavail = r->bavail;
  stbuf->f_files = r->files;
  stbuf->f_ffree = r->ffree;
  stbuf->f_favail = r->favail;
  stbuf->f_fsid = r->fsid;
  stbuf->f_flag = r->flag;
  stbuf->f_namemax = r->namemax;

  return 0;
}

/* Nautilus loves to use access(2) to test everything about a file,
 * such as whether it's executable.  Therefore treat this a lot like
 * mount_local_getattr.
 */
static int
mount_local_access (const char *path, int mask)
{
  struct stat statbuf;
  int r;
  struct fuse_context *fuse;
  int ok = 1;
  DECL_G ();
  DEBUG_CALL ("%s, %d", path, mask);

  if (g->ml_read_only && (mask & W_OK))
    return -EROFS;

  r = mount_local_getattr (path, &statbuf);
  if (r < 0 || mask == F_OK) {
    debug (g, "%s: mount_local_getattr returned r = %d", path, r);
    return r;
  }

  fuse = fuse_get_context ();

  /* Root user should be able to access everything, so only bother
   * with these fine-grained tests for non-root.  (RHBZ#1106548).
   */
  if (fuse->uid != 0) {
    if (mask & R_OK)
      ok = ok &&
        (  fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IRUSR
           : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IRGRP
           : statbuf.st_mode & S_IROTH);
    if (mask & W_OK)
      ok = ok &&
        (  fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IWUSR
           : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IWGRP
           : statbuf.st_mode & S_IWOTH);
    if (mask & X_OK)
      ok = ok &&
        (  fuse->uid == statbuf.st_uid ? statbuf.st_mode & S_IXUSR
           : fuse->gid == statbuf.st_gid ? statbuf.st_mode & S_IXGRP
           : statbuf.st_mode & S_IXOTH);
  }

  debug (g, "%s: "
         "testing access mask%s%s%s%s: "
         "caller UID:GID = %ju:%ju, "
         "file UID:GID = %ju:%ju, "
         "file mode = %o, "
         "result = %s",
         path,
         mask & R_OK ? " R_OK" : "",
         mask & W_OK ? " W_OK" : "",
         mask & X_OK ? " X_OK" : "",
         mask == 0 ? " 0" : "",
         (uintmax_t) fuse->uid, (uintmax_t) fuse->gid,
         (uintmax_t) statbuf.st_uid, (uintmax_t) statbuf.st_gid,
         statbuf.st_mode,
         ok ? "OK" : "EACCESS");

  return ok ? 0 : -EACCES;
}

static int
mount_local_readlink (const char *path, char *buf, size_t size)
{
  const char *r;
  int free_it = 0;
  size_t len;
  DECL_G ();
  DEBUG_CALL ("%s, %p, %zu", path, buf, size);

  r = rlc_lookup (g, path);
  if (!r) {
    r = guestfs_readlink (g, path);
    if (r == NULL)
      RETURN_ERRNO;
    free_it = 1;
  }

  /* Note this is different from the real readlink(2) syscall.  FUSE wants
   * the string to be always nul-terminated, even if truncated.
   */
  len = strlen (r);
  if (len > size - 1)
    len = size - 1;

  memcpy (buf, r, len);
  buf[len] = '\0';

  if (free_it) {
    char *tmp = (char *) r;
    free (tmp);
  }

  return 0;
}

void
m_free(struct mbuf *m)
{

  DEBUG_CALL("m_free");
  DEBUG_ARG("m = %lx", (long )m);

  if(m) {
	/* Remove from m_usedlist */
	if (m->m_flags & M_USEDLIST)
	   remque(m);

	/* If it's M_EXT, free() it */
	if (m->m_flags & M_EXT)
	   free(m->m_ext);

	/*
	 * Either free() it or put it on the free list
	 */
	if (m->m_flags & M_DOFREE) {
		m->slirp->mbuf_alloced--;
		free(m);
	} else if ((m->m_flags & M_FREELIST) == 0) {
		insque(m,&m->slirp->m_freelist);
		m->m_flags = M_FREELIST; /* Clobber other flags */
	}
  } /* if(m) */
}

void
tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m,
            tcp_seq ack, tcp_seq seq, int flags)
{
	register int tlen;
	int win = 0;

	DEBUG_CALL("tcp_respond");
	DEBUG_ARG("tp = %lx", (long)tp);
	DEBUG_ARG("ti = %lx", (long)ti);
	DEBUG_ARG("m = %lx", (long)m);
	DEBUG_ARG("ack = %u", ack);
	DEBUG_ARG("seq = %u", seq);
	DEBUG_ARG("flags = %x", flags);

	if (tp)
		win = sbspace(&tp->t_socket->so_rcv);
        if (m == NULL) {
		if ((m = m_get()) == NULL)
			return;
#ifdef TCP_COMPAT_42
		tlen = 1;
#else
		tlen = 0;
#endif
		m->m_data += IF_MAXLINKHDR;
		*mtod(m, struct tcpiphdr *) = *ti;
		ti = mtod(m, struct tcpiphdr *);
		flags = TH_ACK;
	} else {

/*
 * Read from so's socket into sb_snd, updating all relevant sbuf fields
 * NOTE: This will only be called if it is select()ed for reading, so
 * a read() of 0 (or less) means it's disconnected
 */
int
soread(struct socket *so)
{
	int n, nn;
	struct sbuf *sb = &so->so_snd;
	struct iovec iov[2];

	DEBUG_CALL("soread");
	DEBUG_ARG("so = %p", so);

	/*
	 * No need to check if there's enough room to read.
	 * soread wouldn't have been called if there weren't
	 */
	sopreprbuf(so, iov, &n);

#ifdef HAVE_READV
	nn = readv(so->s, (struct iovec *)iov, n);
	DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
#else
	nn = qemu_recv(so->s, iov[0].iov_base, iov[0].iov_len,0);
#endif
	if (nn <= 0) {
		if (nn < 0 && (errno == EINTR || errno == EAGAIN))
			return 0;
		else {
			DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));
			sofcantrcvmore(so);
			tcp_sockclosed(sototcpcb(so));
			return -1;
		}
	}

#ifndef HAVE_READV
	/*
	 * If there was no error, try and read the second time round
	 * We read again if n = 2 (ie, there's another part of the buffer)
	 * and we read as much as we could in the first read
	 * We don't test for <= 0 this time, because there legitimately
	 * might not be any more data (since the socket is non-blocking),
	 * a close will be detected on next iteration.
	 * A return of -1 wont (shouldn't) happen, since it didn't happen above
	 */
	if (n == 2 && nn == iov[0].iov_len) {
            int ret;
            ret = qemu_recv(so->s, iov[1].iov_base, iov[1].iov_len,0);
            if (ret > 0)
                nn += ret;
        }

	DEBUG_MISC((dfd, " ... read nn = %d bytes\n", nn));
#endif

	/* Update fields */
	sb->sb_cc += nn;
	sb->sb_wptr += nn;
	if (sb->sb_wptr >= (sb->sb_data + sb->sb_datalen))
		sb->sb_wptr -= sb->sb_datalen;
	return nn;
}

/*
 * Send a single message to the TCP at address specified by
 * the given TCP/IP header.  If m == 0, then we make a copy
 * of the tcpiphdr at ti and send directly to the addressed host.
 * This is used to force keep alive messages out using the TCP
 * template for a connection tp->t_template.  If flags are given
 * then we send a message back to the TCP which originated the
 * segment ti, and discard the mbuf containing it and any other
 * attached mbufs.
 *
 * In any case the ack and sequence number of the transmitted
 * segment are as specified by the parameters.
 */
void
tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti, struct mbuf *m,
            tcp_seq ack, tcp_seq seq, int flags)
{
	register int tlen;
	int win = 0;

	DEBUG_CALL("tcp_respond");
	DEBUG_ARG("tp = %p", tp);
	DEBUG_ARG("ti = %p", ti);
	DEBUG_ARG("m = %p", m);
	DEBUG_ARG("ack = %u", ack);
	DEBUG_ARG("seq = %u", seq);
	DEBUG_ARG("flags = %x", flags);

	if (tp)
		win = sbspace(&tp->t_socket->so_rcv);
        if (m == NULL) {
		if (!tp || (m = m_get(tp->t_socket->slirp)) == NULL)
			return;
		tlen = 0;
		m->m_data += IF_MAXLINKHDR;
		*mtod(m, struct tcpiphdr *) = *ti;
		ti = mtod(m, struct tcpiphdr *);
		flags = TH_ACK;
	} else {

size_t sopreprbuf(struct socket *so, struct iovec *iov, int *np)
{
    int n, lss, total;
    struct sbuf *sb = &so->so_snd;
    int len = sb->sb_datalen - sb->sb_cc;
    int mss = so->so_tcpcb->t_maxseg;

    DEBUG_CALL("sopreprbuf");
    DEBUG_ARG("so = %lx", (long )so);

    len = sb->sb_datalen - sb->sb_cc;

    if (len <= 0)
        return 0;

    iov[0].iov_base = sb->sb_wptr;
    iov[1].iov_base = NULL;
    iov[1].iov_len = 0;
    if (sb->sb_wptr < sb->sb_rptr) {
        iov[0].iov_len = sb->sb_rptr - sb->sb_wptr;
        /* Should never succeed, but... */
        if (iov[0].iov_len > len)
            iov[0].iov_len = len;
        if (iov[0].iov_len > mss)
            iov[0].iov_len -= iov[0].iov_len%mss;
        n = 1;
    } else {
        iov[0].iov_len = (sb->sb_data + sb->sb_datalen) - sb->sb_wptr;
        /* Should never succeed, but... */
        if (iov[0].iov_len > len) iov[0].iov_len = len;
        len -= iov[0].iov_len;
        if (len) {
            iov[1].iov_base = sb->sb_data;
            iov[1].iov_len = sb->sb_rptr - sb->sb_data;
            if(iov[1].iov_len > len)
                iov[1].iov_len = len;
            total = iov[0].iov_len + iov[1].iov_len;
            if (total > mss) {
                lss = total%mss;
                if (iov[1].iov_len > lss) {
                    iov[1].iov_len -= lss;
                    n = 2;
                } else {
                    lss -= iov[1].iov_len;
                    iov[0].iov_len -= lss;
                    n = 1;
                }
            } else
                n = 2;
        } else {
            if (iov[0].iov_len > mss)
                iov[0].iov_len -= iov[0].iov_len%mss;
            n = 1;
        }
    }
    if (np)
        *np = n;

    return iov[0].iov_len + (n - 1) * iov[1].iov_len;
}

static int lpx_USER_attach( struct socket *so,
                            int proto,
                            struct proc *td )
{
    int error;
    int s;
    struct lpxpcb *lpxp = sotolpxpcb(so);

    if (lpxp != NULL)
        return (EINVAL);
    s = splnet();
    error = Lpx_PCB_alloc(so, &lpxpcb, td);
    splx(s);
    if (error == 0) {
        int lpxsends, lpxrecvs;

        lpxsends = 256 * 1024;
        lpxrecvs = 256 * 1024;

        while(lpxsends > 0 && lpxrecvs > 0) {
            error = soreserve(so, lpxsends, lpxrecvs);
            if(error == 0)
                break;
            lpxsends -= (1024*2);
            lpxrecvs -= (1024*2);
        }

        DEBUG_CALL(4, ("lpxsends = %d\n", lpxsends/1024));
    
        //        error = soreserve(so, lpxsendspace, lpxrecvspace);
    }
    
    return (error);
}

struct mbuf *
m_get(void)
{
	register struct mbuf *m;
	int flags = 0;

	DEBUG_CALL("m_get");

	if (m_freelist.m_next == &m_freelist) {
		m = (struct mbuf *)malloc(SLIRP_MSIZE);
		if (m == NULL) goto end_error;
		mbuf_alloced++;
		if (mbuf_alloced > MBUF_THRESH)
			flags = M_DOFREE;
		if (mbuf_alloced > mbuf_max)
			mbuf_max = mbuf_alloced;
	} else {
		m = m_freelist.m_next;
		remque(m);
	}

	
	insque(m,&m_usedlist);
	m->m_flags = (flags | M_USEDLIST);

	
	m->m_size = SLIRP_MSIZE - sizeof(struct m_hdr);
	m->m_data = m->m_dat;
	m->m_len = 0;
        m->m_nextpkt = NULL;
        m->m_prevpkt = NULL;
end_error:
	DEBUG_ARG("m = %lx", (long )m);
	return m;
}

/* Ditto as above. */
static int
mount_local_listxattr (const char *path, char *list, size_t size)
{
  DECL_G ();
  DEBUG_CALL ("%s, %p, %zu", path, list, size);

  const struct guestfs_xattr_list *xattrs;
  int free_attrs = 0;

  xattrs = xac_lookup (g, path);
  if (xattrs == NULL) {
    xattrs = guestfs_lgetxattrs (g, path);
    if (xattrs == NULL)
      RETURN_ERRNO;
    free_attrs = 1;
  }

  /* Calculate how much space is required to hold the result. */
  size_t space = 0;
  size_t len;
  size_t i;
  for (i = 0; i < xattrs->len; ++i) {
    len = strlen (xattrs->val[i].attrname) + 1;
    space += len;
  }

  /* The listxattr man page is unclear, but if list == NULL then we
   * return the space required (the caller then makes a second syscall
   * after allocating the required amount of space).  If list != NULL
   * then it's not clear what we should do, but it appears we should
   * copy as much as possible and return -ERANGE if there's not enough
   * space in the buffer.
   */
  ssize_t r;
  if (list == NULL) {
    r = space;
    goto out;
  }

  r = 0;
  for (i = 0; i < xattrs->len; ++i) {
    len = strlen (xattrs->val[i].attrname) + 1;
    if (size >= len) {
      memcpy (list, xattrs->val[i].attrname, len);
      size -= len;
      list += len;
      r += len;
    } else {
      r = -ERANGE;
      break;
    }
  }

 out:
  if (free_attrs)
    guestfs_free_xattr_list ((struct guestfs_xattr_list *) xattrs);

  return r;
}

int udp_output2_(struct socket *so, struct mbuf *m,
                 const SockAddress*  saddr, 
                 const SockAddress*  daddr,
                 int iptos)
{
    register struct udpiphdr *ui;
    uint32_t  saddr_ip = sock_address_get_ip(saddr);
    uint32_t  daddr_ip = sock_address_get_ip(daddr);
    int       saddr_port = sock_address_get_port(saddr);
    int       daddr_port = sock_address_get_port(daddr);
    int error = 0;

    DEBUG_CALL("udp_output");
	DEBUG_ARG("so = %lx", (long)so);
	DEBUG_ARG("m = %lx", (long)m);
    DEBUG_ARG("saddr = %lx", (long) saddr_ip);
    DEBUG_ARG("daddr = %lx", (long) daddr_ip);

	/*
	 * Adjust for header
	 */
	m->m_data -= sizeof(struct udpiphdr);
	m->m_len += sizeof(struct udpiphdr);

	/*
	 * Fill in mbuf with extended UDP header
	 * and addresses and length put into network format.
	 */
	ui = mtod(m, struct udpiphdr *);
    memset(&ui->ui_i.ih_mbuf, 0 , sizeof(struct mbuf_ptr));
	ui->ui_x1 = 0;
	ui->ui_pr = IPPROTO_UDP;
	ui->ui_len = htons(m->m_len - sizeof(struct ip)); /* + sizeof (struct udphdr)); */
	/* XXXXX Check for from-one-location sockets, or from-any-location sockets */
    ui->ui_src   = ip_seth(saddr_ip);
    ui->ui_dst   = ip_seth(daddr_ip);
    ui->ui_sport = port_seth(saddr_port);
    ui->ui_dport = port_seth(daddr_port);
	ui->ui_ulen = ui->ui_len;

	/*
	 * Stuff checksum and output datagram.
	 */
	ui->ui_sum = 0;
	if (UDPCKSUM) {
	    if ((ui->ui_sum = cksum(m, /* sizeof (struct udpiphdr) + */ m->m_len)) == 0)
		ui->ui_sum = 0xffff;
	}
	((struct ip *)ui)->ip_len = m->m_len;

	((struct ip *)ui)->ip_ttl = IPDEFTTL;
	((struct ip *)ui)->ip_tos = iptos;

	STAT(udpstat.udps_opackets++);

	error = ip_output(so, m);

	return (error);
}