/*
  The oSIP library implements the Session Initiation Protocol (SIP -rfc3261-)
  Copyright (C) 2001,2002,2003,2004,2005,2006,2007 Aymeric MOIZARD jack@atosc.org
  
  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.
  
  This library 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
  Lesser General Public License for more details.
  
  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <osipparser2/osip_port.h>
#include <osipparser2/osip_message.h>
#include <stdlib.h>
#include <stdio.h>

/* allocate a new url structure */
/* OUTPUT: osip_uri_t *url | structure to save results.   */
/* OUTPUT: err_t *err | structure to store error.   */
/* return -1 on error */
int
osip_uri_init (osip_uri_t ** url)
{
  *url = (osip_uri_t *) osip_malloc (sizeof (osip_uri_t));
  if (*url == NULL)
    return -1;
  (*url)->scheme = NULL;
  (*url)->username = NULL;
  (*url)->password = NULL;
  (*url)->host = NULL;
  (*url)->port = NULL;

  osip_list_init (&(*url)->url_params);

  osip_list_init (&(*url)->url_headers);

  (*url)->string = NULL;
  return 0;
}

/* examples:
   sip:j.doe@big.com;maddr=239.255.255.1;ttl=15
   sip:j.doe@big.com
   sip:j.doe:secret@big.com;transport=tcp
   sip:j.doe@big.com?subject=project
   sip:+1-212-555-1212:1234@gateway.com;user=phone
   sip:1212@gateway.com
   sip:alice@10.1.2.3
   sip:alice@example.com
   sip:alice@registrar.com;method=REGISTER

   NOT EQUIVALENT:
   SIP:JUSER@ExAmPlE.CoM;Transport=udp
   sip:juser@ExAmPlE.CoM;Transport=UDP
*/

/* this method search for the separator and   */
/* return it only if it is located before the */
/* second separator. */
char *
next_separator (const char *ch, int separator_osip_to_find, int before_separator)
{
  char *ind;
  char *tmp;

  ind = strchr (ch, separator_osip_to_find);
  if (ind == NULL)
    return NULL;

  tmp = NULL;
  if (before_separator != 0)
    tmp = strchr (ch, before_separator);

  if (tmp != NULL)
    {
      if (ind < tmp)
        return ind;
  } else
    return ind;

  return NULL;
}

/* parse the sip url.                                */
/* INPUT : char *buf | url to be parsed.*/
/* OUTPUT: osip_uri_t *url | structure to save results.   */
/* OUTPUT: err_t *err | structure to store error.   */
/* return -1 on error */
int
osip_uri_parse (osip_uri_t * url, const char *buf)
{
  char *username;
  char *password;
  char *host;
  const char *port;
  const char *params;
  const char *headers;
  const char *tmp;

  /* basic tests */
  if (buf == NULL || buf[0] == '\0')
    return -1;

  tmp = strchr (buf, ':');
  if (tmp == NULL)
    return -1;

  if (tmp - buf < 2)
    return -1;
  url->scheme = (char *) osip_malloc (tmp - buf + 1);
  if (url->scheme == NULL)
    return -1;
  osip_strncpy (url->scheme, buf, tmp - buf);

  if (strlen (url->scheme) < 3 ||
      (0 != osip_strncasecmp (url->scheme, "sip", 3)
       && 0 != osip_strncasecmp (url->scheme, "sips", 4)))
    {                           /* Is not a sipurl ! */
      size_t i = strlen (tmp + 1);

      if (i < 2)
        return -1;
      url->string = (char *) osip_malloc (i + 1);
      if (url->string == NULL)
        return -1;
      osip_strncpy (url->string, tmp + 1, i);
      return 0;
    }

  /*  law number 1:
     if ('?' exists && is_located_after '@')
     or   if ('?' exists && '@' is not there -no username-)
     =====>  HEADER_PARAM EXIST
     =====>  start at index(?)
     =====>  end at the end of url
   */

  /* find the beginning of host */
  username = strchr (buf, ':');
  /* if ':' does not exist, the url is not valid */
  if (username == NULL)
    return -1;

  host = strchr (buf, '@');

  if (host == NULL)
    host = username;
  else if (username[1] == '@')  /* username is empty */
    host = username + 1;
  else
    /* username exists */
    {
      password = next_separator (username + 1, ':', '@');
      if (password == NULL)
        password = host;
      else
        /* password exists */
        {
          if (host - password < 2)
            return -1;
          url->password = (char *) osip_malloc (host - password);
          if (url->password == NULL)
            return -1;
          osip_strncpy (url->password, password + 1, host - password - 1);
          __osip_uri_unescape (url->password);
        }
      if (password - username < 2)
        return -1;
      {
        url->username = (char *) osip_malloc (password - username);
        if (url->username == NULL)
          return -1;
        osip_strncpy (url->username, username + 1, password - username - 1);
        __osip_uri_unescape (url->username);
      }
    }


  /* search for header after host */
  headers = strchr (host, '?');

  if (headers == NULL)
    headers = buf + strlen (buf);
  else
    /* headers exist */
    osip_uri_parse_headers (url, headers);


  /* search for params after host */
  params = strchr (host, ';');  /* search for params after host */
  if (params == NULL)
    params = headers;
  else
    /* params exist */
    {
      char *tmpbuf;

      if (headers - params + 1 < 2)
        return -1;
      tmpbuf = osip_malloc (headers - params + 1);
      if (tmpbuf == NULL)
        return -1;
      tmpbuf = osip_strncpy (tmpbuf, params, headers - params);
      osip_uri_parse_params (url, tmpbuf);
      osip_free (tmpbuf);
    }

  port = params - 1;
  while (port > host && *port != ']' && *port != ':')
    port--;
  if (*port == ':')
    {
      if (host == port)
        port = params;
      else
        {
          if ((params - port < 2) || (params - port > 8))
            return -1;          /* error cases */
          url->port = (char *) osip_malloc (params - port);
          if (url->port == NULL)
            return -1;
          osip_clrncpy (url->port, port + 1, params - port - 1);
        }
  } else
    port = params;
  /* adjust port for ipv6 address */
  tmp = port;
  while (tmp > host && *tmp != ']')
    tmp--;
  if (*tmp == ']')
    {
      port = tmp;
      while (host < port && *host != '[')
        host++;
      if (host >= port)
        return -1;
    }

  if (port - host < 2)
    return -1;
  url->host = (char *) osip_malloc (port - host);
  if (url->host == NULL)
    return -1;
  osip_clrncpy (url->host, host + 1, port - host - 1);

  return 0;
}

void
osip_uri_set_scheme (osip_uri_t * url, char *scheme)
{
  if (url == NULL)
    return;
  url->scheme = scheme;
}

char *
osip_uri_get_scheme (osip_uri_t * url)
{
  if (url == NULL)
    return NULL;
  return url->scheme;
}

void
osip_uri_set_username (osip_uri_t * url, char *username)
{
  if (url == NULL)
    return;
  url->username = username;
}

char *
osip_uri_get_username (osip_uri_t * url)
{
  if (url == NULL)
    return NULL;
  return url->username;
}

void
osip_uri_set_password (osip_uri_t * url, char *password)
{
  if (url == NULL)
    return;
  url->password = password;
}

char *
osip_uri_get_password (osip_uri_t * url)
{
  if (url == NULL)
    return NULL;
  return url->password;
}

void
osip_uri_set_host (osip_uri_t * url, char *host)
{
  if (url == NULL)
    return;
  url->host = host;
}

char *
osip_uri_get_host (osip_uri_t * url)
{
  if (url == NULL)
    return NULL;
  return url->host;
}

void
osip_uri_set_port (osip_uri_t * url, char *port)
{
  if (url == NULL)
    return;
  url->port = port;
}

char *
osip_uri_get_port (osip_uri_t * url)
{
  if (url == NULL)
    return NULL;
  return url->port;
}


int
osip_uri_parse_headers (osip_uri_t * url, const char *headers)
{
  char *and;
  char *equal;

  /* find '=' wich is the separator for one header */
  /* find ';' wich is the separator for multiple headers */

  equal = strchr (headers, '=');
  and = strchr (headers + 1, '&');

  if (equal == NULL)            /* each header MUST have a value */
    return -1;

  do
    {
      char *hname;
      char *hvalue;

      hname = (char *) osip_malloc (equal - headers);
      if (hname == NULL)
        return -1;
      osip_strncpy (hname, headers + 1, equal - headers - 1);
      __osip_uri_unescape (hname);

      if (and != NULL)
        {
          if (and - equal < 2)
            {
              osip_free (hname);
              return -1;
            }
          hvalue = (char *) osip_malloc (and - equal);
          if (hvalue == NULL)
            {
              osip_free (hname);
              return -1;
            }
          osip_strncpy (hvalue, equal + 1, and - equal - 1);
          __osip_uri_unescape (hvalue);
      } else
        {                       /* this is for the last header (no and...) */
          if (headers + strlen (headers) - equal + 1 < 2)
            {
              osip_free (hname);
              return -1;
            }
          hvalue = (char *) osip_malloc (headers + strlen (headers) - equal + 1);
          if (hvalue == NULL)
            {
              osip_free (hname);
              return -1;
            }
          osip_strncpy (hvalue, equal + 1, headers + strlen (headers) - equal);
          __osip_uri_unescape (hvalue);
        }

      osip_uri_uheader_add (url, hname, hvalue);

      if (and == NULL)          /* we just set the last header */
        equal = NULL;
      else                      /* continue on next header */
        {
          headers = and;
          equal = strchr (headers, '=');
          and = strchr (headers + 1, '&');
          if (equal == NULL)    /* each header MUST have a value */
            return -1;
        }
    }
  while (equal != NULL);
  return 0;
}

int
osip_uri_parse_params (osip_uri_t * url, const char *params)
{
  char *pname;
  char *pvalue;

  const char *comma;
  const char *equal;

  /* find '=' wich is the separator for one param */
  /* find ';' wich is the separator for multiple params */

  equal = next_separator (params + 1, '=', ';');
  comma = strchr (params + 1, ';');

  while (comma != NULL)
    {
      if (equal == NULL)
        {
          equal = comma;
          pvalue = NULL;
      } else
        {
          if (comma - equal < 2)
            return -1;
          pvalue = (char *) osip_malloc (comma - equal);
          if (pvalue == NULL)
            return -1;
          osip_strncpy (pvalue, equal + 1, comma - equal - 1);
          __osip_uri_unescape (pvalue);
        }

      if (equal - params < 2)
        {
          osip_free (pvalue);
          return -1;
        }
      pname = (char *) osip_malloc (equal - params);
      if (pname == NULL)
        {
          osip_free (pvalue);
          return -1;
        }
      osip_strncpy (pname, params + 1, equal - params - 1);
      __osip_uri_unescape (pname);

      osip_uri_uparam_add (url, pname, pvalue);

      params = comma;
      equal = next_separator (params + 1, '=', ';');
      comma = strchr (params + 1, ';');
    }

  /* this is the last header (comma==NULL) */
  comma = params + strlen (params);

  if (equal == NULL)
    {
      equal = comma;            /* at the end */
      pvalue = NULL;
  } else
    {
      if (comma - equal < 2)
        return -1;
      pvalue = (char *) osip_malloc (comma - equal);
      if (pvalue == NULL)
        return -1;
      osip_strncpy (pvalue, equal + 1, comma - equal - 1);
    }

  if (equal - params < 2)
    {
      osip_free (pvalue);
      return -1;
    }
  pname = (char *) osip_malloc (equal - params);
  if (pname == NULL)
    {
      osip_free (pvalue);
      return -1;
    }
  osip_strncpy (pname, params + 1, equal - params - 1);

  osip_uri_uparam_add (url, pname, pvalue);

  return 0;
}

int
osip_uri_to_str (const osip_uri_t * url, char **dest)
{
  char *buf;
  size_t len;
  size_t plen;
  char *tmp;
  const char *scheme;

  *dest = NULL;
  if (url == NULL)
    return -1;
  if (url->host == NULL && url->string == NULL)
    return -1;
  if (url->scheme == NULL && url->string != NULL)
    return -1;
  if (url->string == NULL && url->scheme == NULL)
    scheme = "sip";             /* default is sipurl */
  else
    scheme = url->scheme;

  if (url->string != NULL)
    {
      buf = (char *) osip_malloc (strlen (scheme) + strlen (url->string) + 3);
      if (buf == NULL)
        return -1;
      *dest = buf;
      sprintf (buf, "%s:", scheme);
      buf = buf + strlen (scheme) + 1;
      sprintf (buf, "%s", url->string);
      buf = buf + strlen (url->string);
      return 0;
    }

  len = strlen (scheme) + 1 + strlen (url->host) + 5;
  if (url->username != NULL)
    len = len + (strlen (url->username) * 3) + 1;       /* count escaped char */
  if (url->password != NULL)
    len = len + (strlen (url->password) * 3) + 1;
  if (url->port != NULL)
    len = len + strlen (url->port) + 3;

  buf = (char *) osip_malloc (len);
  if (buf == NULL)
    return -1;
  tmp = buf;

  sprintf (tmp, "%s:", scheme);
  tmp = tmp + strlen (tmp);

  if (url->username != NULL)
    {
      char *tmp2 = __osip_uri_escape_userinfo (url->username);

      sprintf (tmp, "%s", tmp2);
      osip_free (tmp2);
      tmp = tmp + strlen (tmp);
    }
  if ((url->password != NULL) && (url->username != NULL))
    {                           /* be sure that when a password is given, a username is also given */
      char *tmp2 = __osip_uri_escape_password (url->password);

      sprintf (tmp, ":%s", tmp2);
      osip_free (tmp2);
      tmp = tmp + strlen (tmp);
    }
  if (url->username != NULL)
    {                           /* we add a '@' only when username is present... */
      sprintf (tmp, "@");
      tmp++;
    }
  if (strchr (url->host, ':') != NULL)
    {
      sprintf (tmp, "[%s]", url->host);
      tmp = tmp + strlen (tmp);
  } else
    {
      sprintf (tmp, "%s", url->host);
      tmp = tmp + strlen (tmp);
    }
  if (url->port != NULL)
    {
      sprintf (tmp, ":%s", url->port);
      tmp = tmp + strlen (tmp);
    }

  {
    int pos = 0;
    osip_uri_param_t *u_param;

    while (!osip_list_eol (&url->url_params, pos))
      {
        char *tmp1;
        char *tmp2 = NULL;

        u_param = (osip_uri_param_t *) osip_list_get (&url->url_params, pos);

        tmp1 = __osip_uri_escape_uri_param (u_param->gname);
        if (u_param->gvalue == NULL)
          plen = strlen (tmp1) + 2;
        else
          {
            tmp2 = __osip_uri_escape_uri_param (u_param->gvalue);
            plen = strlen (tmp1) + strlen (tmp2) + 3;
          }
        len = len + plen;
        buf = (char *) osip_realloc (buf, len);
        tmp = buf;
        tmp = tmp + strlen (tmp);
        if (u_param->gvalue == NULL)
          sprintf (tmp, ";%s", tmp1);
        else
          {
            sprintf (tmp, ";%s=%s", tmp1, tmp2);
            osip_free (tmp2);
          }
        osip_free (tmp1);
        pos++;
      }
  }

  {
    int pos = 0;
    osip_uri_header_t *u_header;

    while (!osip_list_eol (&url->url_headers, pos))
      {
        char *tmp1;
        char *tmp2;

        u_header = (osip_uri_header_t *) osip_list_get (&url->url_headers, pos);
        tmp1 = __osip_uri_escape_header_param (u_header->gname);

        if (tmp1 == NULL)
          {
            osip_free (buf);
            return -1;
          }

        tmp2 = __osip_uri_escape_header_param (u_header->gvalue);

        if (tmp2 == NULL)
          {
            osip_free (tmp1);
            osip_free (buf);
            return -1;
          }
        plen = strlen (tmp1) + strlen (tmp2) + 4;

        len = len + plen;
        buf = (char *) osip_realloc (buf, len);
        tmp = buf;
        tmp = tmp + strlen (tmp);
        if (pos == 0)
          sprintf (tmp, "?%s=%s", tmp1, tmp2);
        else
          sprintf (tmp, "&%s=%s", tmp1, tmp2);
        osip_free (tmp1);
        osip_free (tmp2);
        pos++;
      }
  }

  *dest = buf;
  return 0;
}


void
osip_uri_free (osip_uri_t * url)
{
  int pos = 0;

  if (url == NULL)
    return;
  osip_free (url->scheme);
  osip_free (url->username);
  osip_free (url->password);
  osip_free (url->host);
  osip_free (url->port);

  osip_uri_param_freelist (&url->url_params);

  {
    osip_uri_header_t *u_header;

    while (!osip_list_eol (&url->url_headers, pos))
      {
        u_header = (osip_uri_header_t *) osip_list_get (&url->url_headers, pos);
        osip_list_remove (&url->url_headers, pos);
        osip_uri_header_free (u_header);
      }
  }

  osip_free (url->string);

  osip_free (url);
}

int
osip_uri_clone (const osip_uri_t * url, osip_uri_t ** dest)
{
  int i;
  osip_uri_t *ur;

  *dest = NULL;
  if (url == NULL)
    return -1;
  if (url->host == NULL && url->string == NULL)
    return -1;

  i = osip_uri_init (&ur);
  if (i == -1)                  /* allocation failed */
    return -1;
  if (url->scheme != NULL)
    ur->scheme = osip_strdup (url->scheme);
  if (url->username != NULL)
    ur->username = osip_strdup (url->username);
  if (url->password != NULL)
    ur->password = osip_strdup (url->password);
  if (url->host != NULL)
    ur->host = osip_strdup (url->host);
  if (url->port != NULL)
    ur->port = osip_strdup (url->port);
  if (url->string != NULL)
    ur->string = osip_strdup (url->string);

  i = osip_list_clone(&url->url_params, &ur->url_params, (int *(*)(void *, void *)) &osip_uri_param_clone);
  if (i != 0)
    {
      osip_uri_free(ur);
      return -1;
    }
  i = osip_list_clone(&url->url_headers, &ur->url_headers, (int *(*)(void *, void *)) &osip_uri_param_clone);
  if (i != 0)
    {
      osip_uri_free(ur);
      return -1;
    }
  *dest = ur;
  return 0;
}

int
osip_uri_param_init (osip_uri_param_t ** url_param)
{
  *url_param = (osip_uri_param_t *) osip_malloc (sizeof (osip_uri_param_t));
  (*url_param)->gname = NULL;
  (*url_param)->gvalue = NULL;
  return 0;
}

void
osip_uri_param_free (osip_uri_param_t * url_param)
{
  osip_free (url_param->gname);
  osip_free (url_param->gvalue);
  osip_free (url_param);
}

int
osip_uri_param_set (osip_uri_param_t * url_param, char *pname, char *pvalue)
{
  url_param->gname = pname;
  /* not needed for url, but for all other generic params */
  osip_clrspace (url_param->gname);
  url_param->gvalue = pvalue;
  if (url_param->gvalue != NULL)
    osip_clrspace (url_param->gvalue);
  return 0;
}

int
osip_uri_param_add (osip_list_t * url_params, char *pname, char *pvalue)
{
  int i;
  osip_uri_param_t *url_param;

  i = osip_uri_param_init (&url_param);
  if (i != 0)
    return -1;
  i = osip_uri_param_set (url_param, pname, pvalue);
  if (i != 0)
    {
      osip_uri_param_free (url_param);
      return -1;
    }
  osip_list_add (url_params, url_param, -1);
  return 0;
}

void
osip_uri_param_freelist (osip_list_t * params)
{
  osip_uri_param_t *u_param;

  while (!osip_list_eol (params, 0))
    {
      u_param = (osip_uri_param_t *) osip_list_get (params, 0);
      osip_list_remove (params, 0);
      osip_uri_param_free (u_param);
    }
}

int
osip_uri_param_get_byname (osip_list_t * params, char *pname,
                           osip_uri_param_t ** url_param)
{
  int pos = 0;
  size_t pname_len;
  osip_uri_param_t *u_param;

  *url_param = NULL;
  if (pname == NULL)
    return -1;
  pname_len = strlen (pname);
  if (pname_len <= 0)
    return -1;
  while (!osip_list_eol (params, pos))
    {
      size_t len;

      u_param = (osip_uri_param_t *) osip_list_get (params, pos);
      len = strlen (u_param->gname);
      if (pname_len == len
          && osip_strncasecmp (u_param->gname, pname, strlen (pname)) == 0)
        {
          *url_param = u_param;
          return 0;
        }
      pos++;
    }
  return -1;
}

int
osip_uri_param_clone (const osip_uri_param_t * uparam, osip_uri_param_t ** dest)
{
  int i;
  osip_uri_param_t *up;

  *dest = NULL;
  if (uparam == NULL)
    return -1;
  if (uparam->gname == NULL)
    return -1;                  /* name is mandatory */

  i = osip_uri_param_init (&up);
  if (i != 0)                   /* allocation failed */
    return -1;
  up->gname = osip_strdup (uparam->gname);
  if (uparam->gvalue != NULL)
    up->gvalue = osip_strdup (uparam->gvalue);
  else
    up->gvalue = NULL;
  *dest = up;
  return 0;
}


#define _ALPHANUM_ "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890\0"
#define _RESERVED_ ";/?:@&=+$\0"
#define _MARK_ "-_.!~*'()\0"

#define _MARK__USER_UNRESERVED_ "-_.!~*'()&=+$,;?/\0"
#define _MARK__PWORD_UNRESERVED_ "-_.!~*'()&=+$,\0"
#define _MARK__URI_PARAM_UNRESERVED_ "-_.!~*'()[]/:&+$\0"
#define _MARK__HEADER_PARAM_UNRESERVED_ "-_.!~*'()[]/?:+$\0"

#define osip_is_alphanum(in) (  \
       (in >= 'a' && in <= 'z') || \
       (in >= 'A' && in <= 'Z') || \
       (in >= '0' && in <= '9'))

char *
__osip_uri_escape_nonascii_and_nondef (const char *string, const char *def)
{
  size_t alloc = strlen (string) + 1;
  size_t length;
  char *ns = osip_malloc (alloc);
  unsigned char in;
  size_t newlen = alloc;
  int index = 0;
  const char *tmp;
  int i;

  length = alloc - 1;
  while (length--)
    {
      in = *string;

      i = 0;
      tmp = NULL;
      if (osip_is_alphanum (in))
        tmp = string;
      else
        {
          for (; def[i] != '\0' && def[i] != in; i++)
            {
            }
          if (def[i] != '\0')
            tmp = string;
        }
      if (tmp == NULL)
        {
          /* encode it */
          newlen += 2;          /* the size grows with two, since this'll become a %XX */
          if (newlen > alloc)
            {
              alloc *= 2;
              ns = osip_realloc (ns, alloc);
              if (!ns)
                return NULL;
            }
          sprintf (&ns[index], "%%%02X", in);
          index += 3;
      } else
        {
          /* just copy this */
          ns[index++] = in;
        }
      string++;
    }
  ns[index] = 0;                /* terminate it */
  return ns;
}

/* user =  *( unreserved / escaped / user-unreserved ) */
const char *userinfo_def = /* implied _ALPHANUM_ */ _MARK__USER_UNRESERVED_;
char *
__osip_uri_escape_userinfo (const char *string)
{
  return __osip_uri_escape_nonascii_and_nondef (string, userinfo_def);
}

/* user =  *( unreserved / escaped / user-unreserved ) */
const char *password_def = _MARK__PWORD_UNRESERVED_;
char *
__osip_uri_escape_password (const char *string)
{
  return __osip_uri_escape_nonascii_and_nondef (string, password_def);
}

const char *uri_param_def = _MARK__URI_PARAM_UNRESERVED_;
char *
__osip_uri_escape_uri_param (char *string)
{
  return __osip_uri_escape_nonascii_and_nondef (string, uri_param_def);
}

const char *header_param_def = _MARK__HEADER_PARAM_UNRESERVED_;
char *
__osip_uri_escape_header_param (char *string)
{
  return __osip_uri_escape_nonascii_and_nondef (string, header_param_def);
}

void
__osip_uri_unescape (char *string)
{
  size_t alloc = strlen (string) + 1;
  unsigned char in;
  int index = 0;
  unsigned int hex;
  char *ptr;

  ptr = string;
  while (--alloc > 0)
    {
      in = *ptr;
      if ('%' == in)
        {
          /* encoded part */
          if (alloc > 2 && sscanf (ptr + 1, "%02X", &hex) == 1)
            {
              in = (unsigned char) hex;
              if (*(ptr + 2) &&
                  ((*(ptr + 2) >= '0' && *(ptr + 2) <= '9') ||
                   (*(ptr + 2) >= 'a' && *(ptr + 2) <= 'f') ||
                   (*(ptr + 2) >= 'A' && *(ptr + 2) <= 'F')))
                {
                  alloc -= 2;
                  ptr += 2;
              } else
                {
                  alloc -= 1;
                  ptr += 1;
                }
            }
          else
            {
              break;
            }
        }

      string[index++] = in;
      ptr++;
    }
  string[index] = 0;            /* terminate it */
}


/* RFC3261 16.5 
 */
int
osip_uri_to_str_canonical (const osip_uri_t * url, char **dest)
{
  int result;

  *dest = NULL;
  result = osip_uri_to_str (url, dest);
  if (result == 0)
    {
      /*
         tmp = strchr(*dest, ";");
         if (tmp !=NULL) {
         buf=strndup(*dest, tmp-(*dest));
         osip_free(*dest);
         *dest=buf;
         }
       */
      __osip_uri_unescape (*dest);
    }
  return result;
}
