X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=svr4%2Fppp_ahdlc.c;fp=svr4%2Fppp_ahdlc.c;h=0000000000000000000000000000000000000000;hb=c3183b45104c236f662e083876812680a7a6e92c;hp=ffbe12078fa435a1b7b38af1a98adcd3b2cae75f;hpb=bfee5a891194098d34e3537de455b832a4c5d36d;p=ppp.git diff --git a/svr4/ppp_ahdlc.c b/svr4/ppp_ahdlc.c deleted file mode 100644 index ffbe120..0000000 --- a/svr4/ppp_ahdlc.c +++ /dev/null @@ -1,775 +0,0 @@ -/* - * ppp_ahdlc.c - STREAMS module for doing PPP asynchronous HDLC. - * - * Copyright (c) 1994 The Australian National University. - * All rights reserved. - * - * Permission to use, copy, modify, and distribute this software and its - * documentation is hereby granted, provided that the above copyright - * notice appears in all copies. This software is provided without any - * warranty, express or implied. The Australian National University - * makes no representations about the suitability of this software for - * any purpose. - * - * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY - * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES - * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF - * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY - * OF SUCH DAMAGE. - * - * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES, - * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS - * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO - * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, - * OR MODIFICATIONS. - * - * $Id: ppp_ahdlc.c,v 1.5 1995/10/27 03:57:10 paulus Exp $ - */ - -/* - * This file is used under Solaris 2. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#ifdef sun -#include -#include -#endif -#include -#include - -#define IFRAME_BSIZE 512 /* Block size to allocate for input */ -#define OFRAME_BSIZE 4096 /* Don't allocb more than this for output */ - -static int ahdlc_open __P((queue_t *, dev_t *, int, int, cred_t *)); -static int ahdlc_close __P((queue_t *, int, cred_t *)); -static int ahdlc_wput __P((queue_t *, mblk_t *)); -static int ahdlc_rput __P((queue_t *, mblk_t *)); -static void stuff_frame __P((queue_t *, mblk_t *)); -static void unstuff_chars __P((queue_t *, mblk_t *)); -static int msg_copy __P((uchar_t *, mblk_t *, int)); - -static struct module_info minfo = { - 0x7d23, "ppp_ahdl", 0, INFPSZ, 4096, 128 -}; - -static struct qinit rinit = { - ahdlc_rput, NULL, ahdlc_open, ahdlc_close, NULL, &minfo, NULL -}; - -static struct qinit winit = { - ahdlc_wput, NULL, NULL, NULL, NULL, &minfo, NULL -}; - -static struct streamtab ahdlc_info = { - &rinit, &winit, NULL, NULL -}; - -#ifdef sun -static struct fmodsw fsw = { - "ppp_ahdl", - &ahdlc_info, - D_NEW | D_MP | D_MTQPAIR -}; - -extern struct mod_ops mod_strmodops; - -static struct modlstrmod modlstrmod = { - &mod_strmodops, - "PPP async HDLC module", - &fsw -}; - -static struct modlinkage modlinkage = { - MODREV_1, - (void *) &modlstrmod, - NULL -}; -#endif /* sun */ - -typedef struct ahdlc_state { - int flags; - mblk_t *cur_frame; - mblk_t *cur_blk; - int inlen; - ushort infcs; - u_int32_t xaccm[8]; - u_int32_t raccm; - int mtu; - int mru; - int unit; - struct pppstat stats; -} ahdlc_state_t; - -/* Values for flags */ -#define ESCAPED 0x100 /* last saw escape char on input */ -#define IFLUSH 0x200 /* flushing input due to error */ - -/* RCV_B7_1, etc., defined in net/pppio.h, are stored in flags also. */ -#define RCV_FLAGS (RCV_B7_1|RCV_B7_0|RCV_ODDP|RCV_EVNP) - -#ifndef sun -# define qprocson(q) -# define qprocsoff(q) -#endif - -/* - * FCS lookup table as calculated by genfcstab. - */ -static u_short fcstab[256] = { - 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, - 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, - 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, - 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, - 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, - 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, - 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, - 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, - 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, - 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, - 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, - 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, - 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, - 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, - 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, - 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, - 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, - 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, - 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, - 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, - 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, - 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, - 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, - 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, - 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, - 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, - 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, - 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, - 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, - 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, - 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, - 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78 -}; - -#ifdef sun -/* - * Entry points for modloading. - */ -int -_init(void) -{ - return mod_install(&modlinkage); -} - -int -_fini(void) -{ - return mod_remove(&modlinkage); -} - -int -_info(mip) - struct modinfo *mip; -{ - return mod_info(&modlinkage, mip); -} -#endif - -/* - * STREAMS module entry points. - */ -static int -ahdlc_open(q, devp, flag, sflag, credp) - queue_t *q; - dev_t *devp; - int flag, sflag; - cred_t *credp; -{ - ahdlc_state_t *sp; - - if (q->q_ptr == 0) { - sp = (ahdlc_state_t *) kmem_zalloc(sizeof(ahdlc_state_t), KM_SLEEP); - if (sp == 0) - return ENOSR; - q->q_ptr = sp; - WR(q)->q_ptr = sp; - sp->xaccm[0] = ~0; - sp->xaccm[3] = 0x60000000; - sp->mru = 1500; - qprocson(q); - } - return 0; -} - -static int -ahdlc_close(q, flag, credp) - queue_t *q; - int flag; - cred_t *credp; -{ - ahdlc_state_t *state; - - qprocsoff(q); - if (q->q_ptr != 0) { - state = (ahdlc_state_t *) q->q_ptr; - if (state->cur_frame != 0) { - freemsg(state->cur_frame); - state->cur_frame = 0; - } - kmem_free(q->q_ptr, sizeof(ahdlc_state_t)); - } - return 0; -} - -static int -ahdlc_wput(q, mp) - queue_t *q; - mblk_t *mp; -{ - ahdlc_state_t *state; - struct iocblk *iop; - int error; - mblk_t *np; - struct ppp_stats *psp; - - state = (ahdlc_state_t *) q->q_ptr; - switch (mp->b_datap->db_type) { - case M_DATA: - /* - * A data packet - do character-stuffing and FCS, and - * send it onwards. - */ - stuff_frame(q, mp); - freemsg(mp); - break; - - case M_IOCTL: - iop = (struct iocblk *) mp->b_rptr; - error = EINVAL; - switch (iop->ioc_cmd) { - case PPPIO_XACCM: - if (iop->ioc_count < sizeof(u_int32_t) - || iop->ioc_count > sizeof(ext_accm)) - break; - bcopy(mp->b_cont->b_rptr, (caddr_t)state->xaccm, iop->ioc_count); - state->xaccm[2] &= 0x40000000; /* don't escape 0x5e */ - state->xaccm[3] |= 0x60000000; /* do escape 0x7d, 0x7e */ - iop->ioc_count = 0; - error = 0; - break; - - case PPPIO_RACCM: - if (iop->ioc_count != sizeof(u_int32_t)) - break; - bcopy(mp->b_cont->b_rptr, (caddr_t)&state->raccm, - sizeof(u_int32_t)); - iop->ioc_count = 0; - error = 0; - break; - - case PPPIO_GCLEAN: - np = allocb(sizeof(int), BPRI_HI); - if (np == 0) { - error = ENOSR; - break; - } - if (mp->b_cont != 0) - freemsg(mp->b_cont); - mp->b_cont = np; - *(int *)np->b_wptr = state->flags & RCV_FLAGS; - np->b_wptr += sizeof(int); - iop->ioc_count = sizeof(int); - error = 0; - break; - - case PPPIO_GETSTAT: - np = allocb(sizeof(struct ppp_stats), BPRI_HI); - if (np == 0) { - error = ENOSR; - break; - } - if (mp->b_cont != 0) - freemsg(mp->b_cont); - mp->b_cont = np; - psp = (struct ppp_stats *) np->b_wptr; - np->b_wptr += sizeof(struct ppp_stats); - bzero((caddr_t)psp, sizeof(struct ppp_stats)); - psp->p = state->stats; - iop->ioc_count = sizeof(struct ppp_stats); - error = 0; - break; - - case PPPIO_LASTMOD: - /* we knew this anyway */ - error = 0; - break; - - default: - error = -1; - break; - } - - if (error < 0) - putnext(q, mp); - else if (error == 0) { - mp->b_datap->db_type = M_IOCACK; - qreply(q, mp); - } else { - mp->b_datap->db_type = M_IOCNAK; - iop->ioc_count = 0; - iop->ioc_error = error; - qreply(q, mp); - } - break; - - case M_CTL: - switch (*mp->b_rptr) { - case PPPCTL_MTU: - state->mtu = ((unsigned short *)mp->b_rptr)[1]; - freemsg(mp); - break; - case PPPCTL_MRU: - state->mru = ((unsigned short *)mp->b_rptr)[1]; - freemsg(mp); - break; - case PPPCTL_UNIT: - state->unit = mp->b_rptr[1]; - break; - default: - putnext(q, mp); - } - break; - - default: - putnext(q, mp); - } - return 0; -} - -static int -ahdlc_rput(q, mp) - queue_t *q; - mblk_t *mp; -{ - mblk_t *np; - uchar_t *cp; - ahdlc_state_t *state; - - switch (mp->b_datap->db_type) { - case M_DATA: - unstuff_chars(q, mp); - freemsg(mp); - break; - - case M_HANGUP: - state = (ahdlc_state_t *) q->q_ptr; - if (state->cur_frame != 0) { - /* XXX would like to send this up for debugging */ - freemsg(state->cur_frame); - state->cur_frame = 0; - state->cur_blk = 0; - } - state->inlen = 0; - state->flags = IFLUSH; - putnext(q, mp); - break; - - default: - putnext(q, mp); - } - return 0; -} - -/* Extract bit c from map m, to determine if c needs to be escaped. */ -#define ESCAPE(c, m) ((m)[(c) >> 5] & (1 << ((c) & 0x1f))) - -static void -stuff_frame(q, mp) - queue_t *q; - mblk_t *mp; -{ - ahdlc_state_t *state; - int ilen, olen, c, extra, i; - mblk_t *omsg, *op, *np; - uchar_t *sp, *sp0, *dp, *dp0, *spend; - ushort_t fcs; - u_int32_t *xaccm, lcp_xaccm[8]; - static uchar_t lcphdr[PPP_HDRLEN] = { 0xff, 0x03, 0xc0, 0x21 }; - uchar_t ppphdr[PPP_HDRLEN]; - - state = (ahdlc_state_t *) q->q_ptr; - ilen = msgdsize(mp); - - /* - * We estimate the length of the output packet as - * 1.25 * input length + 16 (for initial flag, FCS, final flag, slop). - */ - olen = ilen + (ilen >> 2) + 16; - if (olen > OFRAME_BSIZE) - olen = OFRAME_BSIZE; - omsg = op = allocb(olen, BPRI_MED); - if (omsg == 0) - goto bomb; - - /* - * Put in an initial flag for now. We'll remove it later - * if we decide we don't need it. - */ - dp = op->b_wptr; - *dp++ = PPP_FLAG; - --olen; - - /* - * For LCP packets, we must escape all control characters. - * Inspect the first PPP_HDRLEN bytes of the message to - * see whether it is an LCP packet. - * LCP packets must not be A/C or protocol compressed. - */ - xaccm = state->xaccm; - if (msg_copy(ppphdr, mp, PPP_HDRLEN) == PPP_HDRLEN - && bcmp((caddr_t) ppphdr, (caddr_t) lcphdr, PPP_HDRLEN) == 0) { - bcopy((caddr_t) state->xaccm, (caddr_t) lcp_xaccm, sizeof(lcp_xaccm)); - lcp_xaccm[0] = ~0; - xaccm = lcp_xaccm; - } - - sp = mp->b_rptr; - fcs = PPP_INITFCS; - for (;;) { - spend = mp->b_wptr; - extra = sp + olen - spend; - if (extra < 0) { - spend = sp + olen; - extra = 0; - } - /* - * We can safely process the input up to `spend' - * without overrunning the output, provided we don't - * hit more than `extra' characters which need to be escaped. - */ - sp0 = sp; - dp0 = dp; - while (sp < spend) { - c = *sp; - if (ESCAPE(c, xaccm)) { - if (extra > 0) - --extra; - else if (sp < spend - 1) - --spend; - else - break; - fcs = PPP_FCS(fcs, c); - *dp++ = PPP_ESCAPE; - c ^= PPP_TRANS; - } else - fcs = PPP_FCS(fcs, c); - *dp++ = c; - ++sp; - } - ilen -= sp - sp0; - olen -= dp - dp0; - - /* - * At this point, we have emptied an input block - * and/or filled an output block. - */ - if (sp >= mp->b_wptr) { - /* - * We've emptied an input block. Advance to the next. - */ - mp = mp->b_cont; - if (mp == 0) - break; /* all done */ - sp = mp->b_rptr; - } - if (olen < 2) { - /* - * The output block is full. Allocate a new one. - */ - op->b_wptr = dp; - olen = 2 * ilen + 5; - if (olen > OFRAME_BSIZE) - olen = OFRAME_BSIZE; - np = allocb(olen, BPRI_MED); - if (np == 0) - goto bomb; - op->b_cont = np; - op = np; - dp = op->b_wptr; - } - } - - /* - * Append the FCS and closing flag. - * This could require up to 5 characters. - */ - if (olen < 5) { - /* Sigh. Need another block. */ - op->b_wptr = dp; - np = allocb(5, BPRI_MED); - if (np == 0) - goto bomb; - op->b_cont = np; - op = np; - dp = op->b_wptr; - } - c = ~fcs & 0xff; - if (ESCAPE(c, xaccm)) { - *dp++ = PPP_ESCAPE; - c ^= PPP_TRANS; - } - *dp++ = c; - c = (~fcs >> 8) & 0xff; - if (ESCAPE(c, xaccm)) { - *dp++ = PPP_ESCAPE; - c ^= PPP_TRANS; - } - *dp++ = c; - *dp++ = PPP_FLAG; - op->b_wptr = dp; - - /* - * Remove the initial flag, if possible. - */ - if (qsize(q->q_next) > 0) - ++omsg->b_rptr; - - /* - * Update statistics. - */ - state->stats.ppp_obytes += msgdsize(omsg); - state->stats.ppp_opackets++; - - /* - * Send it on. - */ - putnext(q, omsg); - return; - - bomb: - if (omsg != 0) - freemsg(omsg); - state->stats.ppp_oerrors++; - putctl1(RD(q)->q_next, M_CTL, PPPCTL_OERROR); -} - -static unsigned paritytab[8] = { - 0x96696996, 0x69969669, 0x69969669, 0x96696996, - 0x69969669, 0x96696996, 0x96696996, 0x69969669 -}; - -#define UPDATE_FLAGS(c) { \ - if ((c) & 0x80) \ - state->flags |= RCV_B7_1; \ - else \ - state->flags |= RCV_B7_0; \ - if (paritytab[(c) >> 5] & (1 << ((c) & 0x1F))) \ - state->flags |= RCV_ODDP; \ - else \ - state->flags |= RCV_EVNP; \ -} - -/* - * Process received characters. - */ -static void -unstuff_chars(q, mp) - queue_t *q; - mblk_t *mp; -{ - ahdlc_state_t *state; - mblk_t *om; - uchar_t *cp, *cpend, *dp, *dp0; - int c, len, extra, offset; - ushort_t fcs; - - state = (ahdlc_state_t *) q->q_ptr; - state->stats.ppp_ibytes += msgdsize(mp); - cp = mp->b_rptr; - for (;;) { - /* - * Advance to next input block if necessary. - */ - if (cp >= mp->b_wptr) { - mp = mp->b_cont; - if (mp == 0) - break; - cp = mp->b_rptr; - continue; - } - - if ((state->flags & (IFLUSH|ESCAPED)) == 0 - && state->inlen > 0 && (om = state->cur_blk) != 0) { - /* - * Process bulk chars as quickly as possible. - */ - dp = om->b_wptr; - len = om->b_datap->db_lim - dp; /* max # output bytes */ - extra = (mp->b_wptr - cp) - len;/* #input chars - #output bytes */ - if (extra < 0) { - len += extra; /* we'll run out of input first */ - extra = 0; - } - cpend = cp + len; - dp0 = dp; - fcs = state->infcs; - while (cp < cpend) { - c = *cp; - if (c == PPP_FLAG) - break; - ++cp; - UPDATE_FLAGS(c); - if (c == PPP_ESCAPE) { - if (extra > 0) { - --extra; - ++cpend; - } - if (cp >= cpend || (c = *cp) == PPP_FLAG) { - state->flags |= ESCAPED; - break; - } - ++cp; - UPDATE_FLAGS(c); - c ^= PPP_TRANS; - } - *dp++ = c; - fcs = PPP_FCS(fcs, c); - } - state->inlen += dp - dp0; - state->infcs = fcs; - om->b_wptr = dp; - if (cp >= mp->b_wptr) - continue; /* advance to the next mblk */ - } - - c = *cp++; - UPDATE_FLAGS(c); - if (c == PPP_FLAG) { - /* - * End of a frame. - * If the ESCAPE flag is set, the frame ended with - * the frame abort sequence "}~". - */ - om = state->cur_frame; - len = state->inlen; - state->cur_frame = 0; - state->inlen = 0; - if (len == 0 && (state->flags & IFLUSH) == 0) - continue; - state->stats.ppp_ipackets++; - if (om != 0 && (state->flags & (IFLUSH|ESCAPED)) == 0 - && len > PPP_FCSLEN) { - if (state->infcs == PPP_GOODFCS) { - adjmsg(om, -PPP_FCSLEN); /* chop off fcs */ - putnext(q, om); /* bombs away! */ - continue; - } -#if DEBUG - cmn_err(CE_CONT, "ppp_ahdl: bad fcs %x\n", state->infcs); -#endif - } - if (om != 0) - freemsg(om); - state->stats.ppp_ierrors++; - putctl1(q->q_next, M_CTL, PPPCTL_IERROR); - continue; - } - - if (state->flags & IFLUSH) - continue; - if (state->flags & ESCAPED) { - c ^= PPP_TRANS; - state->flags &= ~ESCAPED; - } else if (c == PPP_ESCAPE) { - state->flags |= ESCAPED; - continue; - } - if (state->inlen == 0) { - /* - * First byte of the frame: allocate the first message block. - */ - om = allocb(IFRAME_BSIZE, BPRI_MED); - if (om == 0) { - state->flags |= IFLUSH; - continue; - } - state->cur_frame = om; - state->cur_blk = om; - state->infcs = PPP_INITFCS; - } else { - om = state->cur_blk; - if (om->b_wptr >= om->b_datap->db_lim) { - /* - * Current message block is full. Allocate another one, - * unless we have run out of MRU. - */ - if (state->inlen >= state->mru + PPP_HDRLEN + PPP_FCSLEN) { -#if DEBUG - cmn_err(CE_CONT, "ppp_ahdl: frame too long (%d)\n", - state->inlen); -#endif - state->flags |= IFLUSH; - continue; - } - om = allocb(IFRAME_BSIZE, BPRI_MED); - if (om == 0) { - state->flags |= IFLUSH; - continue; - } - state->cur_blk->b_cont = om; - state->cur_blk = om; - } - } - - if (state->inlen == 0) { - /* - * We don't do address/control & protocol decompression here, - * but we try to put the first byte at an offset such that - * the info field starts on a word boundary. The code here - * will do this except for packets with protocol compression - * but not address/control compression. - */ - if (c != PPP_ALLSTATIONS) { - om->b_wptr += 2; - if (c & 1) - ++om->b_wptr; - om->b_rptr = om->b_wptr; - } - } - - *om->b_wptr++ = c; - ++state->inlen; - state->infcs = PPP_FCS(state->infcs, c); - } -} - -static int -msg_copy(buf, mp, n) - uchar_t *buf; - mblk_t *mp; - int n; -{ - int i; - uchar_t *cp; - - cp = mp->b_rptr; - for (i = 0; i < n; ++i) { - if (cp >= mp->b_wptr) { - do { - if ((mp = mp->b_cont) == 0) - return i; - } while (mp->b_rptr >= mp->b_wptr); - cp = mp->b_rptr; - } - buf[i] = *cp++; - } - return n; -}