solanum/ircd/substitution.c
2021-06-01 12:40:02 -04:00

145 lines
4.1 KiB
C

/*
* Solanum: a slightly advanced ircd
* substitution.c: parses substitution-keyword expansions
*
* Copyright (c) 2006-2007 Ariadne Conill <ariadne@dereferenced.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. 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.
*
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include "stdinc.h"
#include "s_user.h"
#include "snomask.h"
#include "match.h"
#include "substitution.h"
#include "s_assert.h"
/*
* Simple mappings for $foo -> 'bar'.
* Everything is a string, so typing doesn't really matter too
* horribly much right now.
*/
struct substitution_variable
{
char *name;
char *value;
};
/*
* substitution_append_var
*
* Inputs - A variable list (rb_dlink_list), name -> value for mapping to make
* Output - none
* Side Effects - Adds a name->value mapping to a list.
*/
void substitution_append_var(rb_dlink_list *varlist, const char *name, const char *value)
{
struct substitution_variable *tmp = rb_malloc(sizeof(struct substitution_variable));
tmp->name = rb_strdup(name);
tmp->value = rb_strdup(value);
rb_dlinkAddAlloc(tmp, varlist);
}
/*
* substitution_free
*
* Inputs - A rb_dlink_list of markup variables to free.
* Outputs - none
* Side Effects - Empties a list of markup variables.
*/
void substitution_free(rb_dlink_list *varlist)
{
rb_dlink_node *nptr, *nptr2;
RB_DLINK_FOREACH_SAFE(nptr, nptr2, varlist->head)
{
struct substitution_variable *tmp = (struct substitution_variable *) nptr->data;
rb_dlinkDestroy(nptr, varlist);
rb_free(tmp->name);
rb_free(tmp->value);
rb_free(tmp);
}
}
/*
* substitution_parse
*
* Inputs - A markup string, rb_dlink-list of markup values
* Output - A string which has been markup-replaced.
* Side Effects - Strings larger than BUFSIZE are terminated.
*/
char *substitution_parse(const char *fmt, rb_dlink_list *varlist)
{
static char buf[BUFSIZE];
const char *ptr;
char *bptr = buf;
for (ptr = fmt; *ptr != '\0' && bptr - buf < BUFSIZE; ptr++) {
if (*ptr != '$') {
*bptr++ = *ptr;
} else if (*(ptr + 1) == '{') {
char varname[BUFSIZE] = { 0 };
char *vptr = varname;
rb_dlink_node *nptr;
/* break out ${var} */
for (ptr += 2; *ptr != '\0'; ptr++) {
if (*ptr == '$') {
ptr--;
break;
} else if (*ptr == '}') {
break;
} else if (vptr < &varname[sizeof(varname) - 1]) {
*vptr++ = *ptr;
}
}
RB_DLINK_FOREACH(nptr, varlist->head) {
struct substitution_variable *val = (struct substitution_variable *) nptr->data;
if (!rb_strcasecmp(varname, val->name)) {
rb_strlcpy(bptr, val->value, sizeof(buf) - (bptr - buf));
bptr += strlen(val->value);
if (bptr >= &buf[sizeof(buf)]) {
bptr = &buf[sizeof(buf) - 1];
}
break;
}
}
/* don't increment ptr into a following string if the '}' is missing */
if (*ptr == '\0')
break;
}
}
*bptr = '\0';
return buf;
}