static uschar *
checkexpand(uschar *s, address_item *addr, uschar *name, int type)
{
uschar *t;
uschar *ss = expand_string(s);
if (ss == NULL)
{
addr->transport_return = FAIL;
addr->message = string_sprintf("Expansion of \"%s\" failed in %s transport: "
"%s", s, name, expand_string_message);
return NULL;
}
if (type != cke_text) for (t = ss; *t != 0; t++)
{
int c = *t;
if (mac_isprint(c)) continue;
if (type == cke_hdr && c == '\n' && (t[1] == ' ' || t[1] == '\t')) continue;
s = string_printing(s);
addr->transport_return = FAIL;
addr->message = string_sprintf("Expansion of \"%s\" in %s transport "
"contains non-printing character %d", s, name, c);
return NULL;
}
return ss;
}
const uschar *
string_printing2(const uschar *s, BOOL allow_tab)
{
int nonprintcount = 0;
int length = 0;
const uschar *t = s;
uschar *ss, *tt;
while (*t != 0)
{
int c = *t++;
if (!mac_isprint(c) || (!allow_tab && c == '\t')) nonprintcount++;
length++;
}
if (nonprintcount == 0) return s;
/* Get a new block of store guaranteed big enough to hold the
expanded string. */
ss = store_get(length + nonprintcount * 3 + 1);
/* Copy everying, escaping non printers. */
t = s;
tt = ss;
while (*t != 0)
{
int c = *t;
if (mac_isprint(c) && (allow_tab || c != '\t')) *tt++ = *t++;
else
{
*tt++ = '\\';
switch (*t)
{
case '\n':
*tt++ = 'n';
break;
case '\r':
*tt++ = 'r';
break;
case '\b':
*tt++ = 'b';
break;
case '\v':
*tt++ = 'v';
break;
case '\f':
*tt++ = 'f';
break;
case '\t':
*tt++ = 't';
break;
default:
sprintf(CS tt, "%03o", *t);
tt += 3;
break;
}
t++;
}
}
*tt = 0;
return ss;
}