Source Code 1994 March/Source_Code_CD-ROM_Walnut_Creek_March_1994.iso/compsrcs/unix/volume27/clc/part20

Text File | 1993-11-28 | 26.4 KB | 1,159 lines

Newsgroups: comp.sources.unix
From: [e-mail] (Panos Tsirigotis)
Subject: v27i126: clc - C Libraries Collection, Part20/20
References: <[e-mail]>
Sender: [e-mail]
Approved: [e-mail]

Submitted-By: [e-mail] (Panos Tsirigotis)
Posting-Number: Volume 27, Issue 126
Archive-Name: clc/part20

#! /bin/sh
# This is a shell archive.  Remove anything before this line, then unpack
# it by saving it into a file and typing "sh file".  To overwrite existing
# files, type "sh file -c".  You can also feed this as standard input via
# unshar, or by typing "sh <file", e.g..  If this archive is complete, you
# will see the following message at the end:
#        "End of archive 20 (of 20)."
# Contents:  libs/src/sio/siosup.c
# Wrapped by panos@eclipse on Sun Nov 28 14:48:18 1993
PATH=/bin:/usr/bin:/usr/ucb ; export PATH
if test -f 'libs/src/sio/siosup.c' -a "${1}" != "-c" ; then
  echo shar: Will not clobber existing file \"'libs/src/sio/siosup.c'\"
else
echo shar: Extracting \"'libs/src/sio/siosup.c'\" \(24088 characters\)
sed "s/^X//" >'libs/src/sio/siosup.c' <<'END_OF_FILE'
X/*
X * (c) Copyright 1992, 1993 by Panagiotis Tsirigotis
X * All rights reserved.  The file named COPYRIGHT specifies the terms
X * and conditions for redistribution.
X */
X
Xstatic char RCSid[] = "$Id: siosup.c,v 8.4 1993/03/17 07:35:24 panos Exp $" ;
X
X#include <sys/types.h>
X#include <sys/stat.h>
X#include <fcntl.h>
X
X#include "impl.h"
X#include "sio.h"
X
X#ifdef EVENTS
X#include "events.h"
X#endif
X
Xchar *malloc() ;
Xchar *realloc() ;
X
X
Xstatic __sio_descriptor_t static_descriptor_array[ N_SIO_DESCRIPTORS ] ;
Xstatic int n_descriptors = N_SIO_DESCRIPTORS ;
X__sio_descriptor_t *__sio_descriptors = static_descriptor_array ;
X
X#ifdef EVENTS
Xstatic events_s static___sio_events[ N_SIO_DESCRIPTORS ] ;
Xevents_s *__sio_events = static___sio_events ;
X#endif
X
X
X/*
X * Code for finalization
X */
X#ifdef HAS_FINALIZATION_FUNCTION
Xstatic int finalizer_installed ;
X
XSIO_DEFINE_FIN( sio_cleanup )
X{
X   (void) Sflush( SIO_FLUSH_ALL ) ;
X}
X#endif /* HAS_FINALIZATION_FUNCTION */
X
X
X
X#ifdef HAS_MMAP
X
X#define CHAR_NULL                ((char *)0)
X
X/*
X * PAGES_MAPPED gives the size of each map unit in pages
X */
X#define PAGES_MAPPED                2
X
Xstatic size_t map_unit_size = 0 ;            /* bytes */
Xstatic size_t page_size = 0 ;                    /* bytes */
X
Xstatic mapd_s static_mapd_array[ N_SIO_DESCRIPTORS ] ;
Xstatic mapd_s *mmap_descriptors = static_mapd_array ;
X
X#define MDP( fd )                ( mmap_descriptors + (fd) )
X
X
X/*
X * NOTES ON MEMORY MAPPING:
X *
X *     1. Memory mapping works only for file descriptors opened for input
X *        2. Mapping an object to a part of the address space where another
X *            object is mapped will cause the old mapping to disappear (i.e. mmap
X *            will not fail)
X *
X * Memory mapping interface:
X *        SIO_MMAP : maps a file into a portion of the address space.
X *        SIO_MUNMAP: unmap a portion of the address space
X *        SIO_MNEED: indicate to the OS that we will need a portion of
X *                         our address space.
X *
X * The map_unit_size variable defines how much of the file is mapped at
X * a time. It is a multiple of the operating system page size. It is
X * not less than SIO_BUFFER_SIZE unless SIO_BUFFER_SIZE is not a
X * multiple of the page size (so the SIO_BUFFER_SIZE overrides
X * PAGES_MAPPED).
X *
X * NOTE: All memory mapping code is in this file only
X */
X
X
X/*
X * Macros used by the memory mapping code
X */
X#define FIRST_TIME( dp )                    ( dp->buf == NULL )
X#define FATAL_ERROR( msg )                    perror( msg ), exit( 1 )
X
X/*
X * Functions to support memory mapping:
X *
X *            try_memory_mapping
X *            buffer_setup
X *            __sio_switch
X *            initial_map
X *            map_unit
X */
X
X/*
X * try_memory_mapping attempts to setup the specified descriptor
X * for memory mapping.
X * It returns FAILURE if it fails and SUCCESS if it is successful.
X * If HAS_MMAP is not defined, the function is defined to be FAILURE.
X *
X * Sets fields:
X *        memory_mapped:             TRUE or FALSE
X *
X * Also sets the following fields if memory_mapped is TRUE:
X *    file_offset, file_size, buffer_size
X *
X */
XPRIVATE status_e try_memory_mapping( fd, idp, stp )
X    int fd ;
X    register __sio_id_t *idp ;
X    struct stat *stp ;
X{
X    int access ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_TRY_MEMORY_MAPPING ) ;
X#endif
X
X    /*
X     * Do not try memory mapping if:
X     *        1) The file is not a regular file
X     *        2) The file is a regular file but has zero-length
X     *        3) The file pointer is not positioned at the beginning of the file
X     *        4) The fcntl to obtain the file descriptor flags fails
X     *        5) The access mode is not O_RDONLY or O_RDWR
X     *
X     * The operations are done in this order to avoid the system calls
X     * if possible.
X     */
X    if ( ( ( stp->st_mode & S_IFMT ) != S_IFREG ) ||
X          ( stp->st_size == 0 ) ||
X          ( lseek( fd, (long)0, 1 ) != 0 ) ||
X          ( ( access = fcntl( fd, F_GETFL, 0 ) ) == -1 ) ||
X          ( ( access &= 0x3 ) != O_RDONLY && access != O_RDWR ) )
X    {
X        idp->memory_mapped = FALSE ;
X        return( FAILURE ) ;
X    }
X
X    /*
X     * Determine page_size and map_unit_size.
X     * Note that the code works even if PAGES_MAPPED is 0.
X     */
X    if ( page_size == 0 )
X    {
X        page_size = getpagesize() ;
X        map_unit_size = page_size * PAGES_MAPPED ;
X        if ( map_unit_size < SIO_BUFFER_SIZE )
X            if ( map_unit_size > 0 && SIO_BUFFER_SIZE % map_unit_size == 0 )
X                map_unit_size = SIO_BUFFER_SIZE ;
X            else
X                map_unit_size = page_size ;
X    }
X
X    MDP(fd)->file_offset = 0 ;
X    MDP(fd)->file_size = stp->st_size ;
X    idp->buffer_size = map_unit_size ;
X    idp->buf = CHAR_NULL ;
X    idp->memory_mapped = TRUE ;
X
X    return( SUCCESS ) ;
X}
X
X
X/*
X * Copy the current_unit to the primary buffer
X *
X * Sets fields: start, end, nextb
X * Also sets the file pointer
X */
XPRIVATE void buffer_setup( idp, fd, mu_cur, mu_next )
X    __sio_id_t *idp ;
X    int fd ;
X    struct map_unit *mu_cur ;
X    struct map_unit *mu_next ;
X{
X    off_t new_offset ;
X
X    sio_memcopy( mu_cur->addr, idp->buf, mu_cur->valid_bytes ) ;
X    idp->start = idp->buf ;
X    idp->end = idp->buf + mu_cur->valid_bytes ;
X    idp->nextb = idp->buf + ( idp->nextb - mu_cur->addr ) ;
X
X    if ( mu_next->addr != CHAR_NULL )
X        new_offset = MDP(fd)->file_offset - mu_next->valid_bytes ;
X    else
X        new_offset = MDP(fd)->file_offset ;
X    (void) lseek( fd, new_offset, 0 ) ;
X}
X
X
X/*
X * Switch from memory mapping to buffered I/O
X * If any mapping has occured, then the current unit is
X * copied into the buffer that is allocated.
X * Any data in the next unit is ignored.
X * We rely on idp->buf to identify the current unit (so it
X * better be equal to the address of one of the units).
X *
X * Sets fields:
X *            start, end, nextb
X */
Xstatus_e __sio_switch( idp, fd )
X    register __sio_id_t *idp ;
X    int fd ;
X{
X    register mapd_s *mdp = MDP( fd ) ;
X    struct map_unit *mu_cur, *mu_next ;
X    unsigned buffer_size = idp->buffer_size ;
X    char *buf_addr = idp->buf ;
X    int first_time = FIRST_TIME( idp ) ;
X    void buffer_setup() ;
X    status_e setup_read_buffer() ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_SIO_SWITCH ) ;
X#endif
X
X    /*
X     * Initialize stream for buffering
X     */
X    if ( setup_read_buffer( idp, buffer_size ) == FAILURE )
X        return( FAILURE ) ;
X
X    if ( ! first_time )
X    {
X        /*
X         * Find current, next unit
X         */
X        if ( buf_addr == mdp->first_unit.addr )
X        {
X            mu_cur = &mdp->first_unit ;
X            mu_next = &mdp->second_unit ;
X        }
X        else
X        {
X            mu_cur = &mdp->second_unit ;
X            mu_next = &mdp->first_unit ;
X        }
X
X        buffer_setup( idp, fd, mu_cur, mu_next ) ;
X        /*
X         * Destroy all mappings
X         */
X        (void) SIO_MUNMAP( mu_cur->addr, mu_cur->mapped_bytes ) ;
X        if ( mu_next->addr != NULL )
X            (void) SIO_MUNMAP( mu_next->addr, mu_next->mapped_bytes ) ;
X    }
X    else
X        idp->start = idp->end = idp->nextb = idp->buf ;
X
X    idp->memory_mapped = FALSE ;
X    return( SUCCESS ) ;
X}
X
X
X/*
X * initial_map does the first memory map on the file descriptor.
X * It attempts to map both units.
X * The mapping always starts at file offset 0.
X *
X * SETS FIELDS:
X *            first_unit.*, second_unit.*
X *            file_offset
X *
X * Returns:
X *            number of bytes mapped in first_unit
X *    or
X *            0 to indicate that mmap failed.
X */
XPRIVATE int initial_map( mdp, fd )
X    register mapd_s *mdp ;
X    int fd ;
X{
X    register caddr_t addr ;
X    register size_t requested_length = 2 * map_unit_size ;
X    register size_t mapped_length = MIN( mdp->file_size, requested_length ) ;
X    size_t bytes_left ;
X    register size_t bytes_in_unit ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_INITIAL_MAP ) ;
X#endif
X
X    addr = SIO_MMAP( CHAR_NULL, mapped_length, fd, 0 ) ;
X    if ( (int) addr == -1 )
X        return( 0 ) ;
X
X    SIO_MNEED( addr, mapped_length ) ;
X
X    /*
X     * Map as much as possible in the first unit
X     */
X    bytes_in_unit = MIN( mapped_length, map_unit_size ) ;
X    mdp->first_unit.addr             = addr ;
X    mdp->first_unit.mapped_bytes     = bytes_in_unit ;
X    mdp->first_unit.valid_bytes     = bytes_in_unit ;
X
X    /*
X     * If there is more, map it in the second unit.
X     */
X    bytes_left = mapped_length - bytes_in_unit ;
X    if ( bytes_left > 0 )
X    {
X        mdp->second_unit.addr             = addr + bytes_in_unit ;
X        mdp->second_unit.mapped_bytes = bytes_left ;
X        mdp->second_unit.valid_bytes     = bytes_left ;
X    }
X    else
X        mdp->second_unit.addr             = CHAR_NULL ;
X
X    mdp->file_offset = mapped_length ;
X
X    return( mdp->first_unit.valid_bytes ) ;
X}
X
X
X/*
X * ALGORITHM:
X *
X *        if ( there are more bytes in the file )
X *        {
X *            map them at the given unit
X *            update offset
X *            issue SIO_MNEED()
X *        }
X *        else
X *            unmap the unit
X */
XPRIVATE status_e map_unit( mdp, fd, mup )
X    register mapd_s *mdp ;
X    int fd ;
X    register struct map_unit *mup ;
X{
X    register size_t bytes_left = mdp->file_size - mdp->file_offset ;
X    register size_t bytes_to_map = MIN( bytes_left, map_unit_size ) ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_MAP_UNIT ) ;
X#endif
X
X    if ( bytes_to_map > 0 )
X    {
X        if ( (int) SIO_MMAP( mup->addr, bytes_to_map,
X                                                            fd, mdp->file_offset ) == -1 )
X            return( FAILURE ) ;            /* XXX: need to do more ? */
X
X        mup->valid_bytes = bytes_to_map ;
X        ASSERT( mup->valid_bytes <= mup->mapped_bytes ) ;
X        mdp->file_offset += bytes_to_map ;
X        SIO_MNEED( mup->addr, mup->valid_bytes ) ;
X    }
X    else
X    {
X        (void) SIO_MUNMAP( mup->addr, mup->mapped_bytes ) ;
X        mup->addr = CHAR_NULL ;
X    }
X    return( SUCCESS ) ;
X}
X
X#else
X
X#define try_memory_mapping( x, y, z )                FAILURE
X
X#endif /* HAS_MMAP */
X
X
XPRIVATE status_e setup_read_buffer( idp, buf_size )
X    register __sio_id_t *idp ;
X    unsigned buf_size ;
X{
X    register char *buf ;
X
X    /*
X     * First allocate space for 2 buffers: primary and auxiliary
X     */
X    buf = malloc( buf_size * 2 ) ;
X    if ( buf == NULL )
X        return( FAILURE ) ;
X
X    /*
X     * The descriptor buf field should point to the start of the main buffer
X     */
X    idp->buf = buf + buf_size ;
X    idp->buffer_size = buf_size ;
X    return( SUCCESS ) ;
X}
X
X
XPRIVATE status_e init_input_stream( idp, fd, stp )
X    register __sio_id_t *idp ;
X    int fd ;
X    struct stat *stp ;
X{
X#ifdef EVENTS
X    EVENT( fd, EV_INIT_INPUT_STREAM ) ;
X#endif
X
X    /*
X     * First initialize the fields relevant to buffering: buf, buffer_size
X     */
X    if ( try_memory_mapping( fd, idp, stp ) == FAILURE )
X    {
X        /*
X         * Try to use normal buffering
X         */
X        unsigned buf_size = (unsigned)
X                            ( stp->st_blksize ? stp->st_blksize : SIO_BUFFER_SIZE ) ;
X
X        if ( setup_read_buffer( idp, buf_size ) == FAILURE )
X            return( FAILURE ) ;
X    }
X
X     /*
X     * Initialize remaining descriptor fields
X     */
X    idp->max_line_length = 2 * idp->buffer_size - 1 ;
X    idp->start = idp->end = idp->nextb = idp->buf ;
X    idp->tied_fd = SIO_NO_TIED_FD ;
X
X    return( SUCCESS ) ;
X}
X
X
XPRIVATE status_e init_output_stream( odp, fd, stp )
X    register __sio_od_t *odp ;
X    int fd ;
X    struct stat *stp ;
X{
X    register unsigned buf_size ;
X    register char *buf ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_INIT_OUTPUT_STREAM ) ;
X#endif
X
X    buf_size = (unsigned)
X                        ( stp->st_blksize ? stp->st_blksize : SIO_BUFFER_SIZE ) ;
X    buf = malloc( buf_size ) ;
X    if ( buf == NULL )
X        return( FAILURE ) ;
X
X    /*
X     * Initialize buffering fields
X     */
X    odp->buf = buf ;
X    odp->buffer_size = buf_size ;
X    odp->buf_end = odp->buf + buf_size ;
X
X    /*
X     * Initialize remaining fields
X     */
X    odp->start = odp->nextb = odp->buf ;
X    if ( isatty( fd ) )
X        odp->buftype = SIO_LINEBUF ;
X
X    if ( fd == 2 )
X        odp->buftype = SIO_NOBUF ;
X
X    return( SUCCESS ) ;
X}
X
X
X#ifndef HAS_ISATTY
X
X#ifdef HAS_SYSVTTY
X
X#include <termio.h>
X
XPRIVATE int isatty( fd )
X    int fd ;
X{
X    struct termio t ;
X
X    if ( ioctl( fd, TCGETA, &t ) == -1 && errno == ENOTTY )
X        return( FALSE ) ;
X    else
X        return( TRUE ) ;
X}
X#endif    /* HAS_SYSVTTY */
X
X#ifdef HAS_BSDTTY
X
X#include <sgtty.h>
X
XPRIVATE int isatty( fd )
X    int fd ;
X{
X    struct sgttyb s ;
X
X    if ( ioctl( fd, TIOCGETP, &s ) == -1 && errno == ENOTTY )
X        return( FALSE ) ;
X    else
X        return( TRUE ) ;
X}
X#endif    /* HAS_BSDTTY */
X
X#endif    /* ! HAS_ISATTY */
X
X
X/*
X * Initialize stream I/O for a file descriptor.
X *
X * Arguments:
X *        fd:                file descriptor
X *        dp:                descriptor pointer
X *        stream_type:     either __SIO_INPUT_STREAM or __SIO_OUTPUT_STREAM
X *
X * Returns
X *        0             if successful
X *      SIO_ERR    if the file descriptor is not valid (sets errno)
X *   exits        if stream_type is not __SIO_INPUT_STREAM or __SIO_OUTPUT_STREAM
X */
Xint __sio_init( dp, fd, stream_type )
X    register __sio_descriptor_t *dp ;
X    int fd ;
X    enum __sio_stream stream_type ;
X{
X    struct stat st ;
X    void terminate() ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_SIO_INIT ) ;
X#endif
X
X    if ( fstat( fd, &st ) == -1 )
X        return( SIO_ERR ) ;
X
X    switch ( stream_type )
X    {
X        case __SIO_INPUT_STREAM:
X            if ( init_input_stream( IDP( dp ), fd, &st ) == FAILURE )
X                return( SIO_ERR ) ;
X            break ;
X
X        case __SIO_OUTPUT_STREAM:
X            if ( init_output_stream( ODP( dp ), fd, &st ) == FAILURE )
X                return( SIO_ERR ) ;
X            break ;
X
X        default:
X            terminate( "SIO __sio_init: bad stream type (internal error).\n" ) ;
X            /* NOTREACHED */
X    }
X    dp->stream_type = stream_type ;
X    dp->initialized = TRUE ;
X
X#ifdef HAS_FINALIZATION_FUNCTION
X    if ( ! finalizer_installed )
X    {
X        if ( ! SIO_FINALIZE( sio_cleanup ) )
X        {
X            char *s = "SIO __sio_init: finalizer installation failed\n" ;
X
X            (void) write( 2, s, strlen( s ) ) ;
X        }
X        else
X            finalizer_installed = TRUE ;
X    }
X#endif /* HAS_FINALIZATION_FUNCTION */
X
X    return( 0 ) ;
X}
X
X
X/*
X * __sio_writef writes the data in the buffer to the file descriptor.
X *
X * It tries to write as much data as possible until either all data
X * are written or an error occurs. EINTR is the only error that is
X * ignored.
X * In case an error occurs but some data were written, that number
X * is returned instead of SIO_ERR.
X *
X * Fields modified:
X *        When successful: start, nextb
X *        When not successful: start
X *
X * Return value:
X *        Number of bytes written
X *        SIO_ERR, if write(2) fails and no data were written
X */
Xint __sio_writef( odp, fd )
X    register __sio_od_t *odp ;
X    int fd ;
X{
X    register int b_in_buffer ;
X    register int cc_total = 0 ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_SIO_WRITEF ) ;
X#endif
X
X    /*
X     * Make sure we don't exceed the buffer limits
X     *    Maybe we should log this ?            XXX
X     */
X    if ( odp->nextb > odp->buf_end )
X        odp->nextb = odp->buf_end ;
X
X    b_in_buffer = odp->nextb - odp->start ;
X
X    if ( b_in_buffer == 0 )
X        return( 0 ) ;
X
X    for ( ;; )
X    {
X        register int cc ;
X
X        cc = write( fd, odp->start, b_in_buffer ) ;
X        if ( cc == b_in_buffer )
X        {
X            odp->start = odp->nextb = odp->buf ;
X            cc_total += cc ;
X            break ;
X        }
X        else if ( cc == -1 )
X        {
X            if ( errno == EINTR )
X                continue ;
X            else
X                /*
X                 * If some bytes were written, return that number, otherwise
X                 * return SIO_ERR
X                 */
X                return( ( cc_total != 0 ) ? cc_total : SIO_ERR ) ;
X        }
X        else            /* some bytes were written */
X        {
X            odp->start += cc ;            /* advance start of buffer */
X            b_in_buffer -= cc ;            /* decrease number bytes left in buffer */
X            cc_total += cc ;                /* count the bytes that were written */
X        }
X    }
X    return( cc_total ) ;
X}
X
X
X/*
X * __sio_readf reads data from the file descriptor into the buffer.
X * Unlike __sio_writef it does NOT try to read as much data as will fit
X * in the buffer. It ignores EINTR.
X *
X * Returns: # of bytes read or SIO_ERR
X *
X * Fields set:
X *         If it does not return SIO_ERR, it sets start, nextb, end
X *            If it returns SIO_ERR, it does not change anything
X */
Xint __sio_readf( idp, fd )
X    register __sio_id_t *idp ;
X    int fd ;
X{
X    register int cc ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_SIO_READF ) ;
X#endif
X
X    /*
X     * First check for a tied fd and flush the stream if necessary
X     *
X     *         XXX    the return value of __sio_writef is not checked.
X     *                    Is that right ?
X     */
X    if ( idp->tied_fd != SIO_NO_TIED_FD )
X        (void) __sio_writef( &__SIO_OD( idp->tied_fd ), idp->tied_fd ) ;
X
X#ifdef HAS_MMAP
X    if ( idp->memory_mapped )
X    {
X        register mapd_s *mdp = MDP( fd ) ;
X
X        /*
X         * The functions initial_map and map_unit may fail.
X         * In either case, we switch to buffered I/O.
X         * If initial_map fails, we have read no data, so we
X         * should perform a read(2).
X         * If map_unit fails (for the next unit), we still have
X         * the data in the current unit, so we can return.
X         */
X        if ( FIRST_TIME( idp ) )
X        {
X            cc = initial_map( mdp, fd ) ;
X            if ( cc > 0 )
X                idp->buf = mdp->first_unit.addr ;
X            else
X            {
X                if ( __sio_switch( idp, fd ) == FAILURE )
X                    return( SIO_ERR ) ;
X                cc = -1 ;
X            }
X        }
X        else
X        {
X            register struct map_unit *mu_cur, *mu_next ;
X
X            if ( idp->buf == mdp->first_unit.addr )
X            {
X                mu_cur = &mdp->first_unit ;
X                mu_next = &mdp->second_unit ;
X            }
X            else
X            {
X                mu_cur = &mdp->second_unit ;
X                mu_next = &mdp->first_unit ;
X            }
X
X            if ( mu_next->addr != NULL )
X            {
X                idp->buf = mu_next->addr ;
X                cc = mu_next->valid_bytes ;
X                /*
X                 * XXX:  Here we may return SIO_ERR even though there
X                 *           are data in the current unit because the switch
X                 *           fails (possibly because malloc failed).
X                 */
X                if ( map_unit( mdp, fd, mu_cur ) == FAILURE &&
X                                        __sio_switch( idp, fd ) == FAILURE )
X                    return( SIO_ERR ) ;
X            }
X            else
X                cc = 0 ;
X        }
X        if ( cc >= 0 )
X        {
X            idp->end = idp->buf + cc ;
X            idp->start = idp->nextb = idp->buf ;
X            return( cc ) ;
X        }
X    }
X#endif /* HAS_MMAP */
X
X    for ( ;; )
X    {
X        cc = read( fd, idp->buf, (int) idp->buffer_size ) ;
X        if ( cc == -1 )
X            if ( errno == EINTR )
X                continue ;
X            else
X                return( SIO_ERR ) ;
X        else
X            break ;
X    }
X
X    idp->end = idp->buf + cc ;
X    idp->start = idp->nextb = idp->buf ;
X    return( cc ) ;
X}
X
X
X/*
X * __sio_extend_buffer is used by Srdline to extend the buffer
X * If successful, it returns the number of bytes that have been read.
X * If it fails (because of end-of-file or I/O error), it returns 0 or -1.
X *
X * Fields modified:
X *     idp->start points to the start of the buffer area (which is in the
X *     auxiliary buffer)
X *        Also, if successful, idp->nextb is set to idp->buf, idp->end is modified.
X */
Xint __sio_extend_buffer( idp, fd, b_left )
X    register __sio_id_t *idp ;
X    int fd ;
X    register int b_left ;
X{
X    register int b_read ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_SIO_EXTEND_BUFFER ) ;
X#endif
X
X    /*
X     * copy to auxiliary buffer
X     */
X    if ( b_left )
X        sio_memcopy( idp->nextb, idp->buf - b_left, b_left ) ;
X    b_read = __sio_readf( idp, fd ) ;
X    idp->start = idp->buf - b_left ;
X    return( b_read ) ;
X}
X
X
X/*
X * __sio_more tries to read more data from the given file descriptor iff
X * there is free space in the buffer.
X * __sio_more is used only by Srdline and only AFTER __sio_extend_buffer
X * has been called. This implies that
X *        a) this is not a memory mapped file
X *        b) __sio_readf has been called (so we don't need to check for tied fd's
X *
X * Fields modified (only if successful):
X *            idp->end
X *
X * Return value: the number of bytes read.
X */
Xint __sio_more( idp, fd )
X    register __sio_id_t *idp ;
X    int fd ;
X{
X    register int b_left = &idp->buf[ idp->buffer_size ] - idp->end ;
X    register int cc ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_SIO_MORE ) ;
X#endif
X
X    if ( b_left <= 0 )
X        return( 0 ) ;
X
X    for ( ;; )
X    {
X        cc = read( fd, idp->end, b_left ) ;
X        if ( cc >= 0 )
X        {
X            idp->end += cc ;
X            return( cc ) ;
X        }
X        else
X            if ( errno == EINTR )
X                continue ;
X            else
X                return( SIO_ERR ) ;
X    }
X}
X
X
X/*
X * Finalize a buffer by unmapping the file or freeing the malloc'ed memory
X */
Xint Sdone( fd )
X    int fd ;
X{
X    register __sio_descriptor_t *dp = &__sio_descriptors[ fd ] ;
X
X#ifdef EVENTS
X    EVENT( fd, EV_SDONE ) ;
X#endif
X
X    if ( ! DESCRIPTOR_INITIALIZED( dp ) )
X    {
X        errno = EBADF ;
X        return( SIO_ERR ) ;
X    }
X
X    switch ( dp->stream_type )
X    {
X        case __SIO_INPUT_STREAM:
X            {
X                register __sio_id_t *idp = IDP( dp ) ;
X
X#ifdef HAS_MMAP
X                if ( idp->memory_mapped )
X                {
X                    register mapd_s *mdp = MDP( fd ) ;
X
X                    if ( mdp->first_unit.addr != CHAR_NULL )
X                        (void) SIO_MUNMAP( mdp->first_unit.addr,
X                                                        mdp->first_unit.mapped_bytes ) ;
X                    if ( mdp->second_unit.addr != CHAR_NULL )
X                        (void) SIO_MUNMAP( mdp->second_unit.addr,
X                                                        mdp->second_unit.mapped_bytes ) ;
X                    idp->memory_mapped = FALSE ;
X                }
X                else
X#endif    /* HAS_MMAP */
X                    free( idp->buf - idp->buffer_size ) ;
X                    idp->nextb = idp->end = NULL ;
X            }
X            break ;
X
X        case __SIO_OUTPUT_STREAM:
X            {
X                register __sio_od_t *odp = ODP( dp ) ;
X
X                if ( Sflush( fd ) == SIO_ERR )
X                    return( SIO_ERR ) ;
X                free( odp->buf ) ;
X                odp->nextb = odp->buf_end = NULL ;
X            }
X            break ;
X
X        default:
X            terminate( "SIO Sdone: bad stream type\n" ) ;
X    }
X
X    dp->initialized = FALSE ;
X    return( 0 ) ;
X}
X
X
XPRIVATE char *expand( area, old_size, new_size, is_static )
X    char *area ;
X    unsigned old_size, new_size ;
X    int is_static ;
X{
X    char *new_area ;
X
X    if ( is_static )
X    {
X        if ( ( new_area = malloc( new_size ) ) == NULL )
X            return( NULL ) ;
X        sio_memcopy( area, new_area, old_size ) ;
X    }
X    else
X        if ( ( new_area = realloc( area, new_size ) ) == NULL )
X            return( NULL ) ;
X    return( new_area ) ;
X}
X
X
X#include <sys/time.h>
X#include <sys/resource.h>
X
XPRIVATE int get_fd_limit()
X{
X#ifdef RLIMIT_NOFILE
X
X    struct rlimit rl ;
X
X    (void) getrlimit( RLIMIT_NOFILE, &rl ) ;
X    return( rl.rlim_cur ) ;
X
X#else
X
X    return( N_SIO_DESCRIPTORS ) ;
X
X#endif
X}
X
X/*
X * Expand the descriptor array (and if we use memory mapping the
X * memory mapping descriptors). We first expand the memory mapping
X * descriptors.
X * There is no problem if the expansion of the SIO descriptors fails
X * (i.e. there is no need to undo anything).
X */
Xint Smorefds()
X{
X    char *p ;
X    int is_static ;
X    unsigned new_size, old_size ;
X    int n_fds = get_fd_limit() ;
X
X    if ( n_fds <= n_descriptors )
X        return( 0 ) ;
X
X#ifdef EVENTS
X    old_size = n_descriptors * sizeof( events_s ) ;
X    new_size = n_fds * sizeof( events_s ) ;
X    is_static = ( __sio_events == static___sio_events ) ;
X    p = expand( (char *)__sio_events, old_size, new_size, is_static ) ;
X    if ( p == NULL )
X        return( SIO_ERR ) ;
X    __sio_events = (events_s *) p ;
X
X    /*
X     * Clear the codes field of the extra events structs.
X     * We have to do this because a non-null codes field implies that
X     * events recording is on for that fd
X     */
X    {
X        int i ;
X
X        for ( i = n_descriptors ; i < n_fds ; i++ )
X            __sio_events[i].codes = NULL ;
X    }
X#endif    /* EVENTS */
X
X#ifdef HAS_MMAP
X    old_size = n_descriptors * sizeof( mapd_s ) ;
X    new_size = n_fds * sizeof( mapd_s ) ;
X    is_static = ( mmap_descriptors == static_mapd_array ) ;
X    p = expand( (char *)mmap_descriptors, old_size, new_size, is_static ) ;
X    if ( p == NULL )
X        return( SIO_ERR ) ;
X    mmap_descriptors = (mapd_s *) p ;
X#endif    /* HAS_MMAP */
X
X    old_size = n_descriptors * sizeof( __sio_descriptor_t ) ;
X    new_size = n_fds * sizeof( __sio_descriptor_t ) ;
X    is_static =  ( __sio_descriptors == static_descriptor_array ) ;
X    p = expand( (char *)__sio_descriptors, old_size, new_size, is_static ) ;
X    if ( p == NULL )
X        return( SIO_ERR ) ;
X    __sio_descriptors = (__sio_descriptor_t *) p ;
X
X    n_descriptors = n_fds ;
X    return( 0 ) ;
X}
X
X
X#ifdef EVENTS
X
X/*
X * Enable recording of events for the specified file descriptor
X */
Xint __sio_enable_events( fd )
X    int fd ;
X{
X    char *p = malloc( EVENT_ENTRIES * sizeof( short ) ) ;
X
X    if ( p == NULL )
X        return( SIO_ERR ) ;
X
X    __sio_events[ fd ].codes = (short *) p ;
X    return( 0 ) ;
X}
X
X
X/*
X * Disable recording of events for the specified file descriptor
X */
Xvoid __sio_disable_events( fd )
X    int fd ;
X{
X    if ( __sio_events[ fd ].codes != NULL )
X    {
X        free( (char *) __sio_events[ fd ].codes ) ;
X        __sio_events[ fd ].codes = NULL ;
X    }
X}
X
X
X/*
X * Move stored events to buf
X */
Xint __sio_get_events( fd, buf, size )
X    int fd ;
X    char *buf ;
X    int size ;
X{
X    events_s *evp = &__sio_events[ fd ] ;
X    int bufentries ;
X    int range1, range2 ;
X    int diff ;
X    char *p ;
X    int cc ;
X    int cc_total ;
X    int move_entries ;
X
X    if ( evp->codes == NULL )
X        return( 0 ) ;
X
X    diff = evp->next - evp->start ;
X    if ( diff == 0 )
X        return( 0 ) ;
X
X    if ( diff > 0 )
X    {
X        range1 = diff ;
X        range2 = 0 ;
X    }
X    else
X    {
X        range1 = EVENT_ENTRIES - evp->start ;
X        range2 = evp->next ;
X    }
X
X    bufentries = size / sizeof( short ) ;
X    p = buf ;
X    cc_total = 0 ;
X
X    move_entries = MIN( range1, bufentries ) ;
X    cc = move_entries * sizeof( short ) ;
X    sio_memcopy( (char *) &evp->codes[ evp->start ], p, cc ) ;
X    cc_total += cc ;
X    p += cc ;
X    bufentries -= range1 ;
X    ADD( evp->start, move_entries ) ;
X
X    if ( bufentries == 0 || range2 == 0 )
X        return( cc_total ) ;
X
X    move_entries = MIN( range2, bufentries ) ;
X    cc = move_entries * sizeof( short ) ;
X    sio_memcopy(  (char *) &evp->codes[ evp->start ], p, cc ) ;
X    cc_total += cc ;
X    ADD( evp->start, move_entries ) ;
X
X    return( cc_total ) ;
X}
X
X#endif     /* EVENTS */
X
X
X/*
X * Simple function that prints the string s at stderr and then calls
X * exit
X */
XPRIVATE void terminate( s )
X    char *s ;
X{
X    (void) write( 2, s, strlen( s ) ) ;
X    (void) abort() ;
X    exit( 1 ) ;                /* in case abort fails */
X}
X
END_OF_FILE
if test 24088 -ne `wc -c <'libs/src/sio/siosup.c'`; then
    echo shar: \"'libs/src/sio/siosup.c'\" unpacked with wrong size!
fi
# end of 'libs/src/sio/siosup.c'
fi
echo shar: End of archive 20 \(of 20\).
cp /dev/null ark20isdone
MISSING=""
for I in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 ; do
    if test ! -f ark${I}isdone ; then
    MISSING="${MISSING} ${I}"
    fi
done
if test "${MISSING}" = "" ; then
    echo You have unpacked all 20 archives.
    rm -f ark[1-9]isdone ark[1-9][0-9]isdone
else
    echo You still need to unpack the following archives:
    echo "        " ${MISSING}
fi
##  End of shell archive.
exit 0