src/server/util/netbuf.c

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
 *
 * THE BSD LICENSE
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the  nor the names of its contributors may be
 * used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * netbuf.c: Handles buffered I/O on network sockets
 *
 * Rob McCool
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

//include "nspr.h"
#include "../public/nsapi.h"
#include "io.h"

//include "buffer.h"


#define NETBUF_RDTIMEOUT 120


/* ----------------------------- netbuf_open ------------------------------ */


NSAPI_PUBLIC netbuf *netbuf_open(SYS_NETFD sd, int sz) {
    netbuf *buf = (netbuf *) malloc(sizeof(netbuf));

    buf->rdtimeout = NETBUF_RDTIMEOUT;
    buf->pos = sz;
    buf->cursize = sz; /* force buffer_next on first getc */
    buf->maxsize = sz;
    buf->sd = sd;

    buf->inbuf = NULL;
    buf->errmsg = NULL;

    return buf;
}


/* ----------------------------- netbuf_close ----------------------------- */


NSAPI_PUBLIC void netbuf_close(netbuf *buf) {
    if(buf->inbuf)
        free(buf->inbuf);
    free(buf);
}


/* ----------------------------- netbuf_replace --------------------------- */


NSAPI_PUBLIC unsigned char * netbuf_replace(netbuf *buf,
    unsigned char *inbuf, int pos, int cursize, int maxsize)
{
    unsigned char *oldbuf = buf->inbuf;

    buf->inbuf = inbuf;
    buf->pos = pos;
    buf->cursize = cursize;
    buf->maxsize = maxsize;

    return oldbuf;
}


/* ----------------------------- netbuf_next ------------------------------ */


NSAPI_PUBLIC int netbuf_next(netbuf *buf, int advance) {
    int n;

    if(!buf->inbuf)
        buf->inbuf = (unsigned char *) malloc(buf->maxsize);

    while(1) {
        switch(n = net_read(buf->sd, (char *)(buf->inbuf), buf->maxsize)) {
        //case IO_EOF:
        case 0:
            return IO_EOF;
        case -1:
            return IO_ERROR;
        //case IO_ERROR:
            //buf->errmsg = system_errmsg();
        //    return IO_ERROR;
        default:
            buf->pos = advance;
            buf->cursize = n;
            return buf->inbuf[0];
        }
    }
}

NSAPI_PUBLIC int netbuf_getbytes(netbuf *buf, char *buffer, int size)
{
    int bytes;

    if (!buf->inbuf) {
        buf->inbuf = (unsigned char *) malloc(buf->maxsize);
    } else {
        if (buf->pos < buf->cursize) {
            int bytes_in_buffer = buf->cursize - buf->pos;

            if (bytes_in_buffer > size)
                bytes_in_buffer = size;

            memcpy(buffer, &(buf->inbuf[buf->pos]), bytes_in_buffer);

            buf->pos += bytes_in_buffer;
            return bytes_in_buffer;
        } else if(buf->pos >= buf->maxsize) {
            return NETBUF_EOF;
        }
    }
    
    if(!buf->sd) {
        return NETBUF_EOF;
    }
    
    /* The netbuf is empty.  Read data directly into the caller's buffer */
    bytes = net_read(buf->sd, buffer, size);
    if (bytes == 0)
        return NETBUF_EOF;
    if (bytes < 0) {
        //buf->errmsg = system_errmsg();
        return NETBUF_ERROR;
    }
    return bytes;
}


/* ----------------------------- netbuf_grab ------------------------------ */


NSAPI_PUBLIC int netbuf_grab(netbuf *buf, int sz) {
    int n;
    
    if(!buf->inbuf) {
        buf->inbuf = (unsigned char *) malloc(sz);
        buf->maxsize = sz;
    }
    else if(sz > buf->maxsize) {
        buf->inbuf = (unsigned char *) realloc(buf->inbuf, sz);
        buf->maxsize = sz;
    }

    //PR_ASSERT(buf->pos == buf->cursize); // TODO
    buf->pos = 0;
    buf->cursize = 0;

    while(1) {
        switch(n = net_read(buf->sd, (char *)(buf->inbuf), sz)) {
        case 0:
            return IO_EOF;
        case -1: {
            //buf->errmsg = system_errmsg();
            return IO_ERROR;
        }
        default:
            buf->cursize = n;
            return n;
        }
    }
}