Quelle sockets.c Sprache: C

/*---------------------------------------------------------------
* Copyright (c) 1999,2000,2001,2002,2003
* The Board of Trustees of the University of Illinois
* All Rights Reserved.
*---------------------------------------------------------------
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software (Iperf) and associated
* documentation files (the "Software"), to deal in the Software
* without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute,
* sublicense, and/or sell copies of the Software, and to permit
* persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
*
* Redistributions of source code must retain the above
* copyright notice, this list of conditions and
* the following disclaimers.
*
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimers in the documentation and/or other materials
* provided with the distribution.
*
*
* Neither the names of the University of Illinois, NCSA,
* nor the names of its contributors may be used to endorse
* or promote products derived from this Software without
* specific prior written permission.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE CONTIBUTORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
* ________________________________________________________________
* National Laboratory for Applied Network Research
* National Center for Supercomputing Applications
* University of Illinois at Urbana-Champaign
* http://www.ncsa.uiuc.edu
* ________________________________________________________________
*
* socket.c
* by Mark Gates <mgates@nlanr.net>
* -------------------------------------------------------------------
* set/getsockopt and read/write wrappers
* ------------------------------------------------------------------- */

#include "headers.h"
#include "util.h"

#ifdef __cplusplus
extern "C" {
#endif

/* -------------------------------------------------------------------
* If inMSS > 0, set the TCP maximum segment size  for inSock.
* Otherwise leave it as the system default.
* ------------------------------------------------------------------- */

const char warn_mss_fail[] = "\
WARNING: attempt to set TCP maxmimum segment size to %d failed.\n\
Setting the MSS may not be implemented on this OS.\n";

const char warn_mss_notset[] =
"WARNING: attempt to set TCP maximum segment size to %d, but got %d\n";

void setsock_tcp_mss( int inSock, int inMSS ) {
#ifdef TCP_MAXSEG
    int rc;
    int newMSS;
    Socklen_t len;

    assert( inSock != INVALID_SOCKET );

    if ( inMSS > 0 ) {
        /* set */
        newMSS = inMSS;
        len = sizeof( newMSS );
        rc = setsockopt( inSock, IPPROTO_TCP, TCP_MAXSEG, (char*) &newMSS,  len );
        if ( rc == SOCKET_ERROR ) {
            fprintf( stderr, warn_mss_fail, newMSS );
            return;
        }

        /* verify results */
        rc = getsockopt( inSock, IPPROTO_TCP, TCP_MAXSEG, (char*) &newMSS, &len );
        WARN_errno( rc == SOCKET_ERROR, "getsockopt TCP_MAXSEG" );
        if ( newMSS != inMSS ) {
            fprintf( stderr, warn_mss_notset, inMSS, newMSS );
        }
    }
#endif
} /* end setsock_tcp_mss */

/* -------------------------------------------------------------------
* returns the TCP maximum segment size
* ------------------------------------------------------------------- */

int getsock_tcp_mss( int inSock ) {
    int theMSS = 0;

#ifdef TCP_MAXSEG
    int rc;
    Socklen_t len;
    assert( inSock >= 0 );

    /* query for MSS */
    len = sizeof( theMSS );
    rc = getsockopt( inSock, IPPROTO_TCP, TCP_MAXSEG, (char*) &theMSS, &len );
    WARN_errno( rc == SOCKET_ERROR, "getsockopt TCP_MAXSEG" );
#endif

    return theMSS;
} /* end getsock_tcp_mss */

/* -------------------------------------------------------------------
* Attempts to reads n bytes from a socket.
* Returns number actually read, or -1 on error.
* If number read < inLen then we reached EOF.
*
* from Stevens, 1998, section 3.9
* ------------------------------------------------------------------- */

ssize_t readn( int inSock, void *outBuf, size_t inLen ) {
    size_t  nleft;
    ssize_t nread;
    char *ptr;

    assert( inSock >= 0 );
    assert( outBuf != NULL );
    assert( inLen > 0 );

    ptr   = (char*) outBuf;
    nleft = inLen;

    while ( nleft > 0 ) {
        nread = read( inSock, ptr, nleft );
        if ( nread < 0 ) {
            if ( errno == EINTR )
                nread = 0;  /* interupted, call read again */
            else
                return -1;  /* error */
        } else if ( nread == 0 )
            break;        /* EOF */

        nleft -= nread;
        ptr   += nread;
    }

    return(inLen - nleft);
} /* end readn */

/* -------------------------------------------------------------------
* Attempts to write  n bytes to a socket.
* returns number actually written, or -1 on error.
* number written is always inLen if there is not an error.
*
* from Stevens, 1998, section 3.9
* ------------------------------------------------------------------- */

ssize_t writen( int inSock, const void *inBuf, size_t inLen ) {
    size_t  nleft;
    ssize_t nwritten;
    const char *ptr;

    assert( inSock >= 0 );
    assert( inBuf != NULL );
    assert( inLen > 0 );

    ptr   = (char*) inBuf;
    nleft = inLen;

    while ( nleft > 0 ) {
        nwritten = write( inSock, ptr, nleft );
        if ( nwritten <= 0 ) {
            if ( errno == EINTR )
                nwritten = 0; /* interupted, call write again */
            else
                return -1;    /* error */
        }

        nleft -= nwritten;
        ptr   += nwritten;
    }

    return inLen;
} /* end writen */

#ifdef __cplusplus
} /* end extern "C" */
#endif

quality93%

¤ Dauer der Verarbeitung: 0.1 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.