diff options
Diffstat (limited to 'sunrpc/xdr_rec.c')
| -rw-r--r-- | sunrpc/xdr_rec.c | 580 |
1 files changed, 580 insertions, 0 deletions
diff --git a/sunrpc/xdr_rec.c b/sunrpc/xdr_rec.c new file mode 100644 index 0000000000..4d0d4ecfb3 --- /dev/null +++ b/sunrpc/xdr_rec.c @@ -0,0 +1,580 @@ +/* @(#)xdr_rec.c 2.2 88/08/01 4.0 RPCSRC */ +/* + * Sun RPC is a product of Sun Microsystems, Inc. and is provided for + * unrestricted use provided that this legend is included on all tape + * media and as a part of the software program in whole or part. Users + * may copy or modify Sun RPC without charge, but are not authorized + * to license or distribute it to anyone else except as part of a product or + * program developed by the user. + * + * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE + * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR + * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. + * + * Sun RPC is provided with no support and without any obligation on the + * part of Sun Microsystems, Inc. to assist in its use, correction, + * modification or enhancement. + * + * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE + * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC + * OR ANY PART THEREOF. + * + * In no event will Sun Microsystems, Inc. be liable for any lost revenue + * or profits or other special, indirect and consequential damages, even if + * Sun has been advised of the possibility of such damages. + * + * Sun Microsystems, Inc. + * 2550 Garcia Avenue + * Mountain View, California 94043 + */ +#if !defined(lint) && defined(SCCSIDS) +static char sccsid[] = "@(#)xdr_rec.c 1.21 87/08/11 Copyr 1984 Sun Micro"; +#endif + +/* + * xdr_rec.c, Implements TCP/IP based XDR streams with a "record marking" + * layer above tcp (for rpc's use). + * + * Copyright (C) 1984, Sun Microsystems, Inc. + * + * These routines interface XDRSTREAMS to a tcp/ip connection. + * There is a record marking layer between the xdr stream + * and the tcp transport level. A record is composed on one or more + * record fragments. A record fragment is a thirty-two bit header followed + * by n bytes of data, where n is contained in the header. The header + * is represented as a htonl(u_long). Thegh order bit encodes + * whether or not the fragment is the last fragment of the record + * (1 => fragment is last, 0 => more fragments to follow. + * The other 31 bits encode the byte length of the fragment. + */ + +#include <stdio.h> +#include <rpc/types.h> +#include <rpc/xdr.h> +#include <netinet/in.h> + +extern long lseek(); + +static u_int fix_buf_size(); + +static bool_t xdrrec_getlong(); +static bool_t xdrrec_putlong(); +static bool_t xdrrec_getbytes(); +static bool_t xdrrec_putbytes(); +static u_int xdrrec_getpos(); +static bool_t xdrrec_setpos(); +static long * xdrrec_inline(); +static void xdrrec_destroy(); + +static struct xdr_ops xdrrec_ops = { + xdrrec_getlong, + xdrrec_putlong, + xdrrec_getbytes, + xdrrec_putbytes, + xdrrec_getpos, + xdrrec_setpos, + xdrrec_inline, + xdrrec_destroy +}; + +/* + * A record is composed of one or more record fragments. + * A record fragment is a two-byte header followed by zero to + * 2**32-1 bytes. The header is treated as a long unsigned and is + * encode/decoded to the network via htonl/ntohl. The low order 31 bits + * are a byte count of the fragment. The highest order bit is a boolean: + * 1 => this fragment is the last fragment of the record, + * 0 => this fragment is followed by more fragment(s). + * + * The fragment/record machinery is not general; it is constructed to + * meet the needs of xdr and rpc based on tcp. + */ + +#define LAST_FRAG ((u_long)(1 << 31)) + +typedef struct rec_strm { + caddr_t tcp_handle; + caddr_t the_buffer; + /* + * out-goung bits + */ + int (*writeit)(); + caddr_t out_base; /* output buffer (points to frag header) */ + caddr_t out_finger; /* next output position */ + caddr_t out_boundry; /* data cannot up to this address */ + u_long *frag_header; /* beginning of curren fragment */ + bool_t frag_sent; /* true if buffer sent in middle of record */ + /* + * in-coming bits + */ + int (*readit)(); + u_long in_size; /* fixed size of the input buffer */ + caddr_t in_base; + caddr_t in_finger; /* location of next byte to be had */ + caddr_t in_boundry; /* can read up to this location */ + long fbtbc; /* fragment bytes to be consumed */ + bool_t last_frag; + u_int sendsize; + u_int recvsize; +} RECSTREAM; + + +/* + * Create an xdr handle for xdrrec + * xdrrec_create fills in xdrs. Sendsize and recvsize are + * send and recv buffer sizes (0 => use default). + * tcp_handle is an opaque handle that is passed as the first parameter to + * the procedures readit and writeit. Readit and writeit are read and + * write respectively. They are like the system + * calls expect that they take an opaque handle rather than an fd. + */ +void +xdrrec_create(xdrs, sendsize, recvsize, tcp_handle, readit, writeit) + register XDR *xdrs; + register u_int sendsize; + register u_int recvsize; + caddr_t tcp_handle; + int (*readit)(); /* like read, but pass it a tcp_handle, not sock */ + int (*writeit)(); /* like write, but pass it a tcp_handle, not sock */ +{ + register RECSTREAM *rstrm = + (RECSTREAM *)mem_alloc(sizeof(RECSTREAM)); + + if (rstrm == NULL) { + (void)fprintf(stderr, "xdrrec_create: out of memory\n"); + /* + * This is bad. Should rework xdrrec_create to + * return a handle, and in this case return NULL + */ + return; + } + /* + * adjust sizes and allocate buffer quad byte aligned + */ + rstrm->sendsize = sendsize = fix_buf_size(sendsize); + rstrm->recvsize = recvsize = fix_buf_size(recvsize); + rstrm->the_buffer = mem_alloc(sendsize + recvsize + BYTES_PER_XDR_UNIT); + if (rstrm->the_buffer == NULL) { + (void)fprintf(stderr, "xdrrec_create: out of memory\n"); + return; + } + for (rstrm->out_base = rstrm->the_buffer; + (u_int)rstrm->out_base % BYTES_PER_XDR_UNIT != 0; + rstrm->out_base++); + rstrm->in_base = rstrm->out_base + sendsize; + /* + * now the rest ... + */ + xdrs->x_ops = &xdrrec_ops; + xdrs->x_private = (caddr_t)rstrm; + rstrm->tcp_handle = tcp_handle; + rstrm->readit = readit; + rstrm->writeit = writeit; + rstrm->out_finger = rstrm->out_boundry = rstrm->out_base; + rstrm->frag_header = (u_long *)rstrm->out_base; + rstrm->out_finger += sizeof(u_long); + rstrm->out_boundry += sendsize; + rstrm->frag_sent = FALSE; + rstrm->in_size = recvsize; + rstrm->in_boundry = rstrm->in_base; + rstrm->in_finger = (rstrm->in_boundry += recvsize); + rstrm->fbtbc = 0; + rstrm->last_frag = TRUE; +} + + +/* + * The reoutines defined below are the xdr ops which will go into the + * xdr handle filled in by xdrrec_create. + */ + +static bool_t +xdrrec_getlong(xdrs, lp) + XDR *xdrs; + long *lp; +{ + register RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); + register long *buflp = (long *)(rstrm->in_finger); + long mylong; + + /* first try the inline, fast case */ + if ((rstrm->fbtbc >= sizeof(long)) && + (((int)rstrm->in_boundry - (int)buflp) >= sizeof(long))) { + *lp = (long)ntohl((u_long)(*buflp)); + rstrm->fbtbc -= sizeof(long); + rstrm->in_finger += sizeof(long); + } else { + if (! xdrrec_getbytes(xdrs, (caddr_t)&mylong, sizeof(long))) + return (FALSE); + *lp = (long)ntohl((u_long)mylong); + } + return (TRUE); +} + +static bool_t +xdrrec_putlong(xdrs, lp) + XDR *xdrs; + long *lp; +{ + register RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); + register long *dest_lp = ((long *)(rstrm->out_finger)); + + if ((rstrm->out_finger += sizeof(long)) > rstrm->out_boundry) { + /* + * this case should almost never happen so the code is + * inefficient + */ + rstrm->out_finger -= sizeof(long); + rstrm->frag_sent = TRUE; + if (! flush_out(rstrm, FALSE)) + return (FALSE); + dest_lp = ((long *)(rstrm->out_finger)); + rstrm->out_finger += sizeof(long); + } + *dest_lp = (long)htonl((u_long)(*lp)); + return (TRUE); +} + +static bool_t /* must manage buffers, fragments, and records */ +xdrrec_getbytes(xdrs, addr, len) + XDR *xdrs; + register caddr_t addr; + register u_int len; +{ + register RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); + register int current; + + while (len > 0) { + current = rstrm->fbtbc; + if (current == 0) { + if (rstrm->last_frag) + return (FALSE); + if (! set_input_fragment(rstrm)) + return (FALSE); + continue; + } + current = (len < current) ? len : current; + if (! get_input_bytes(rstrm, addr, current)) + return (FALSE); + addr += current; + rstrm->fbtbc -= current; + len -= current; + } + return (TRUE); +} + +static bool_t +xdrrec_putbytes(xdrs, addr, len) + XDR *xdrs; + register caddr_t addr; + register u_int len; +{ + register RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); + register int current; + + while (len > 0) { + current = (u_int)rstrm->out_boundry - (u_int)rstrm->out_finger; + current = (len < current) ? len : current; + bcopy(addr, rstrm->out_finger, current); + rstrm->out_finger += current; + addr += current; + len -= current; + if (rstrm->out_finger == rstrm->out_boundry) { + rstrm->frag_sent = TRUE; + if (! flush_out(rstrm, FALSE)) + return (FALSE); + } + } + return (TRUE); +} + +static u_int +xdrrec_getpos(xdrs) + register XDR *xdrs; +{ + register RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; + register long pos; + + pos = lseek((int)rstrm->tcp_handle, (long) 0, 1); + if (pos != -1) + switch (xdrs->x_op) { + + case XDR_ENCODE: + pos += rstrm->out_finger - rstrm->out_base; + break; + + case XDR_DECODE: + pos -= rstrm->in_boundry - rstrm->in_finger; + break; + + default: + pos = (u_int) -1; + break; + } + return ((u_int) pos); +} + +static bool_t +xdrrec_setpos(xdrs, pos) + register XDR *xdrs; + u_int pos; +{ + register RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; + u_int currpos = xdrrec_getpos(xdrs); + int delta = currpos - pos; + caddr_t newpos; + + if ((int)currpos != -1) + switch (xdrs->x_op) { + + case XDR_ENCODE: + newpos = rstrm->out_finger - delta; + if ((newpos > (caddr_t)(rstrm->frag_header)) && + (newpos < rstrm->out_boundry)) { + rstrm->out_finger = newpos; + return (TRUE); + } + break; + + case XDR_DECODE: + newpos = rstrm->in_finger - delta; + if ((delta < (int)(rstrm->fbtbc)) && + (newpos <= rstrm->in_boundry) && + (newpos >= rstrm->in_base)) { + rstrm->in_finger = newpos; + rstrm->fbtbc -= delta; + return (TRUE); + } + break; + } + return (FALSE); +} + +static long * +xdrrec_inline(xdrs, len) + register XDR *xdrs; + int len; +{ + register RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; + long * buf = NULL; + + switch (xdrs->x_op) { + + case XDR_ENCODE: + if ((rstrm->out_finger + len) <= rstrm->out_boundry) { + buf = (long *) rstrm->out_finger; + rstrm->out_finger += len; + } + break; + + case XDR_DECODE: + if ((len <= rstrm->fbtbc) && + ((rstrm->in_finger + len) <= rstrm->in_boundry)) { + buf = (long *) rstrm->in_finger; + rstrm->fbtbc -= len; + rstrm->in_finger += len; + } + break; + } + return (buf); +} + +static void +xdrrec_destroy(xdrs) + register XDR *xdrs; +{ + register RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; + + mem_free(rstrm->the_buffer, + rstrm->sendsize + rstrm->recvsize + BYTES_PER_XDR_UNIT); + mem_free((caddr_t)rstrm, sizeof(RECSTREAM)); +} + + +/* + * Exported routines to manage xdr records + */ + +/* + * Before reading (deserializing from the stream, one should always call + * this procedure to guarantee proper record alignment. + */ +bool_t +xdrrec_skiprecord(xdrs) + XDR *xdrs; +{ + register RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); + + while (rstrm->fbtbc > 0 || (! rstrm->last_frag)) { + if (! skip_input_bytes(rstrm, rstrm->fbtbc)) + return (FALSE); + rstrm->fbtbc = 0; + if ((! rstrm->last_frag) && (! set_input_fragment(rstrm))) + return (FALSE); + } + rstrm->last_frag = FALSE; + return (TRUE); +} + +/* + * Look ahead fuction. + * Returns TRUE iff there is no more input in the buffer + * after consuming the rest of the current record. + */ +bool_t +xdrrec_eof(xdrs) + XDR *xdrs; +{ + register RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); + + while (rstrm->fbtbc > 0 || (! rstrm->last_frag)) { + if (! skip_input_bytes(rstrm, rstrm->fbtbc)) + return (TRUE); + rstrm->fbtbc = 0; + if ((! rstrm->last_frag) && (! set_input_fragment(rstrm))) + return (TRUE); + } + if (rstrm->in_finger == rstrm->in_boundry) + return (TRUE); + return (FALSE); +} + +/* + * The client must tell the package when an end-of-record has occurred. + * The second paraemters tells whether the record should be flushed to the + * (output) tcp stream. (This let's the package support batched or + * pipelined procedure calls.) TRUE => immmediate flush to tcp connection. + */ +bool_t +xdrrec_endofrecord(xdrs, sendnow) + XDR *xdrs; + bool_t sendnow; +{ + register RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); + register u_long len; /* fragment length */ + + if (sendnow || rstrm->frag_sent || + ((u_long)rstrm->out_finger + sizeof(u_long) >= + (u_long)rstrm->out_boundry)) { + rstrm->frag_sent = FALSE; + return (flush_out(rstrm, TRUE)); + } + len = (u_long)(rstrm->out_finger) - (u_long)(rstrm->frag_header) - + sizeof(u_long); + *(rstrm->frag_header) = htonl((u_long)len | LAST_FRAG); + rstrm->frag_header = (u_long *)rstrm->out_finger; + rstrm->out_finger += sizeof(u_long); + return (TRUE); +} + + +/* + * Internal useful routines + */ +static bool_t +flush_out(rstrm, eor) + register RECSTREAM *rstrm; + bool_t eor; +{ + register u_long eormask = (eor == TRUE) ? LAST_FRAG : 0; + register u_long len = (u_long)(rstrm->out_finger) - + (u_long)(rstrm->frag_header) - sizeof(u_long); + + *(rstrm->frag_header) = htonl(len | eormask); + len = (u_long)(rstrm->out_finger) - (u_long)(rstrm->out_base); + if ((*(rstrm->writeit))(rstrm->tcp_handle, rstrm->out_base, (int)len) + != (int)len) + return (FALSE); + rstrm->frag_header = (u_long *)rstrm->out_base; + rstrm->out_finger = (caddr_t)rstrm->out_base + sizeof(u_long); + return (TRUE); +} + +static bool_t /* knows nothing about records! Only about input buffers */ +fill_input_buf(rstrm) + register RECSTREAM *rstrm; +{ + register caddr_t where; + u_int i; + register int len; + + where = rstrm->in_base; + i = (u_int)rstrm->in_boundry % BYTES_PER_XDR_UNIT; + where += i; + len = rstrm->in_size - i; + if ((len = (*(rstrm->readit))(rstrm->tcp_handle, where, len)) == -1) + return (FALSE); + rstrm->in_finger = where; + where += len; + rstrm->in_boundry = where; + return (TRUE); +} + +static bool_t /* knows nothing about records! Only about input buffers */ +get_input_bytes(rstrm, addr, len) + register RECSTREAM *rstrm; + register caddr_t addr; + register int len; +{ + register int current; + + while (len > 0) { + current = (int)rstrm->in_boundry - (int)rstrm->in_finger; + if (current == 0) { + if (! fill_input_buf(rstrm)) + return (FALSE); + continue; + } + current = (len < current) ? len : current; + bcopy(rstrm->in_finger, addr, current); + rstrm->in_finger += current; + addr += current; + len -= current; + } + return (TRUE); +} + +static bool_t /* next two bytes of the input stream are treated as a header */ +set_input_fragment(rstrm) + register RECSTREAM *rstrm; +{ + u_long header; + + if (! get_input_bytes(rstrm, (caddr_t)&header, sizeof(header))) + return (FALSE); + header = (long)ntohl(header); + rstrm->last_frag = ((header & LAST_FRAG) == 0) ? FALSE : TRUE; + rstrm->fbtbc = header & (~LAST_FRAG); + return (TRUE); +} + +static bool_t /* consumes input bytes; knows nothing about records! */ +skip_input_bytes(rstrm, cnt) + register RECSTREAM *rstrm; + long cnt; +{ + register int current; + + while (cnt > 0) { + current = (int)rstrm->in_boundry - (int)rstrm->in_finger; + if (current == 0) { + if (! fill_input_buf(rstrm)) + return (FALSE); + continue; + } + current = (cnt < current) ? cnt : current; + rstrm->in_finger += current; + cnt -= current; + } + return (TRUE); +} + +static u_int +fix_buf_size(s) + register u_int s; +{ + + if (s < 100) + s = 4000; + return (RNDUP(s)); +} |