/* This file is part of GNU Pies.
Copyright (C) 2008, 2009 Sergey Poznyakoff
GNU Pies is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
GNU Pies is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU Pies. If not, see . */
#include "pies.h"
#include
static const char *
meta_expand (struct metadef *def, void *data)
{
if (!def->value)
{
if (def->expand)
return def->expand (def, data);
def->value = "INTERNAL ERROR: NONEXPANDABLE DATA";
}
return def->value;
}
static const char *
find_expansion_char (int c, struct metadef *def, void *data)
{
for (; def->kw; def++)
if (def->kw[1] == 0 && def->kw[0] == c)
return meta_expand (def, data);
return NULL;
}
static const char *
find_expansion_word (const char *kw, size_t len,
struct metadef *def, void *data)
{
for (; def->kw; def++)
if (strlen (def->kw) == len && memcmp (def->kw, kw, len) == 0)
return meta_expand (def, data);
return NULL;
}
char *
meta_expand_string (const char *string, struct metadef *def, void *data)
{
const char *p, *s;
char *res;
struct obstack stk;
if (!string)
return NULL;
obstack_init (&stk);
for (p = string; *p;)
{
char *e;
size_t len = strcspn (p, "$");
obstack_grow (&stk, p, len);
p += len;
if (*p == '$')
{
switch (*++p)
{
case '$':
obstack_grow (&stk, p, 1);
p++;
break;
case '{':
e = strchr (p + 1, '}');
if (e && (s = find_expansion_word (p + 1, e - p - 1, def, data)))
{
obstack_grow (&stk, s, strlen (s));
p = e + 1;
}
else
{
obstack_grow (&stk, p - 1, 2);
p++;
}
break;
default:
if ((s = find_expansion_char (*p, def, data)) != NULL)
len = strlen (s);
else
{
s = p - 1;
len = 1;
}
obstack_grow (&stk, s, len);
p++;
}
}
else
obstack_grow (&stk, p, 1);
}
obstack_1grow (&stk, 0);
res = xstrdup (obstack_finish (&stk));
obstack_free (&stk, NULL);
return res;
}
void
meta_free (struct metadef *def)
{
for (; def->kw; def++)
{
if (def->storage)
{
free (def->storage);
def->value = def->storage = NULL;
}
}
}