petidomo/librfc822/address_sep.c

/*
   $Source$
   $Revision$

   Copyright (C) 2000 by CyberSolutions GmbH, Germany.

   This file is part of OpenPetidomo.

   OpenPetidomo 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 2, or (at your option)
   any later version.

   OpenPetidomo 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.
*/

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#ifdef DEBUG_DMALLOC
#  include <dmalloc.h>
#endif

#include "rfc822.h"

static char *
read_until_next_quote(char * p)
{
    while (*p) {
	if (*p == '"') {
	    p++;
	    break;
	}
	if (*p == '\\' && p[1] != '\0') {
	    p += 2;
	    continue;
	}
	p++;
    }
    return p;
}

static char *
read_until_close_bracket(char * p)
{
    while (*p) {
	if (*p == ')') {
	    p++;
	    break;
	}
	if (*p == '(') {
	    p = read_until_close_bracket(p+1);
	    continue;
	}
	else if (*p == '\\' && p[1] != '\0') {
	    p += 2;
	    continue;
	}
	else if (*p == '"') {
	    p = read_until_next_quote(p+1);
	    continue;
	}
	p++;
    }
    return p;
}

static int
is_source_routing(char * p)
{
    while (*p) {
	if (*p == '(')
	  p = read_until_close_bracket(p+1);

	else if (*p == ' ' || *p == '\t')
	  p++;

	else if (*p == '@' || *p == '<')
	  return 1;

	else
	  return 0;
    }
    return 0;
}

/* Split an RFC822 address line.

   This routine breaks an address line, as specified by RFC822, up
   into separate addresses. The used delimiter is the comma (",").

   The usage of the routine is very similar to strsep(3). More text to
   come.

   AUTHOR: Peter Simons <simons@rhein.de>

 */

char *
rfc822_address_sep(struct rfc822_address_sep_state *   state)
{
    char *   p,
         *   old;
    int      allow_groups;

    /* Sanity checks. */

    assert(state != NULL);
    if (!state) {
	errno = EINVAL;
	return NULL;
    }

    if (*(state->address_line) == '\0')
      return NULL;

    old = p = state->address_line;
    allow_groups = !is_source_routing(p);

    while(*p) {
	if (*p == ',') {
	    *p = '\0';
	    state->address_line = p+1;
	    return old;
	}
	else if (*p == ':' && allow_groups) {
	    old = p+1;
	    state->group_nest++;
	    allow_groups = !is_source_routing(p+1);
	}
	else if (*p == ';') {

	    /* If we are inside an address group, the ';' character is
	       interpreted like a comma. */

	    if (state->group_nest > 0) {
		state->group_nest--;
		*p = ',';
		continue;
	    }
	    else
	      /* do nothing */;
	}
	else if (*p == '(') {
	    p = read_until_close_bracket(p+1);
	    continue;
	}
	else if (*p == '\\' && p[1] != '\0')
	  p++;
	else if (*p == '"') {
	    p = read_until_next_quote(p+1);
	    continue;
	}
	p++;
    }
    state->address_line = p;
    return old;
}