dsslib/html/html.c

/***********************************************************************
*                                                                      *
*               This software is part of the ast package               *
*          Copyright (c) 2010-2011 AT&T Intellectual Property          *
*                      and is licensed under the                       *
*                 Eclipse Public License, Version 1.0                  *
*                    by AT&T Intellectual Property                     *
*                                                                      *
*                A copy of the License is available at                 *
*          http://www.eclipse.org/org/documents/epl-v10.html           *
*         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
*                                                                      *
*              Information and Software Systems Research               *
*                            AT&T Research                             *
*                           Florham Park NJ                            *
*                                                                      *
*                 Glenn Fowler <gsf@research.att.com>                  *
*                                                                      *
***********************************************************************/
#pragma prototyped
/*
 * dss html type library
 *
 * Glenn Fowler
 * AT&T Research
 */

#include <dsslib.h>

static int
html_ref_F(Cx_t* cx, Cxvariable_t* var, Cxoperand_t* ret, Cxoperand_t* arg, int n, void* data, Cxdisc_t* disc)
{
    register char*      s;
    register char*      t;
    register char*      v;
    register int        i;
    register int        c;
    register int        k;
    register int        q;
    char*           b;

    if (!(t = vmnewof(cx->em, 0, char, arg->value.string.size, 1)))
    {
        if (disc->errorf)
            (*disc->errorf)(NiL, disc, ERROR_SYSTEM|2, "out of space");
        return -1;
    }
    b = t;
    i = 0;
    k = 0;
    q = 0;
    v = 0;
    s = arg->value.string.data;
    while (c = *s++)
    {
        if (!i)
        {
            if (c == '<')
                i = 1;
        }
        else if (c == '"')
        {
            if (!(q = !q))
                k = 0;
            else if (k && t > b)
                *t++ = ' ';
        }
        else if (!q)
        {
            if (c == '>')
                i = 0;
            else if (isspace(c))
                v = 0;
            else if (c == '=')
            {
                if (v)
                {
                    n = s - v - 1;
                    if (n == 4 && !strncasecmp(v, "href", 4) || n == 3 && !strncasecmp(v, "src", 3))
                        k = 1;
                }
            }
            else if (!v)
                v = s - 1;
        }
        else if (k)
            *t++ = c;
    }
    if (t > b)
    {
        *t = 0;
        ret->value.string.size = t - b;
        ret->value.string.data = b;
    }
    else
        ret->value = arg->value;
    return 0;
}

static Cxvariable_t dss_functions[] =
{
    CXF("html::ref",    "string",   html_ref_F, "string",
        "Return a space separated list of referenced resources from the HTML tags in the string argument.")
    0
};

Dsslib_t dss_lib_html =
{
    "html",
    "html function support"
    "[-?\n@(#)$Id: dss html function library (AT&T Research) 2010-04-22 $\n]"
    USAGE_LICENSE,
    CXH,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
    &dss_functions[0]
};