rfc822.c

mgcp协议源代码。支持多种编码：g711

  PARAMETER **param;
  if (body) switch (body->type) {
  case TYPEMULTIPART:		/* multi-part */
    for (param = &body->parameter;
	 *param && strcmp ((*param)->attribute,"BOUNDARY");
	 param = &(*param)->next);
    if (!*param) {		/* cookie not set up yet? */
      char tmp[MAILTMPLEN];	/* make cookie not in BASE64 or QUOTEPRINT*/
      sprintf (tmp,"%ld-%ld-%ld=:%ld",(long) gethostid (),random (),time (0),
	       (long) getpid ());
      (*param) = mail_newbody_parameter ();
      (*param)->attribute = cpystr ("BOUNDARY");
      (*param)->value = cpystr (tmp);
    }
    part = body->nested.part;	/* encode body parts */
    do rfc822_encode_body_7bit (env,&part->body);
    while (part = part->next);	/* until done */
    break;
  case TYPEMESSAGE:		/* encapsulated message */
    switch (body->encoding) {
    case ENC7BIT:
      break;
    case ENC8BIT:
      mm_log ("8-bit included message in 7-bit message body",WARN);
      break;
    case ENCBINARY:
      mm_log ("Binary included message in 7-bit message body",WARN);
      break;
    default:
      fatal ("Invalid rfc822_encode_body_7bit message encoding");
    }
    break;			/* can't change encoding */
  default:			/* all else has some encoding */
    switch (body->encoding) {
    case ENC8BIT:		/* encode 8BIT into QUOTED-PRINTABLE */
				/* remember old 8-bit contents */
      f = (void *) body->contents.text.data;
      body->contents.text.data =
	rfc822_8bit (body->contents.text.data,
		     body->contents.text.size,&body->contents.text.size);
      body->encoding = ENCQUOTEDPRINTABLE;
      fs_give (&f);		/* flush old binary contents */
      break;
    case ENCBINARY:		/* encode binary into BASE64 */
				/* remember old binary contents */
      f = (void *) body->contents.text.data;
      body->contents.text.data =
	rfc822_binary ((void *) body->contents.text.data,
		       body->contents.text.size,&body->contents.text.size);
      body->encoding = ENCBASE64;
      fs_give (&f);		/* flush old binary contents */
    default:			/* otherwise OK */
      break;
    }
    break;
  }
}

/* Encode a body for 8BIT transmittal
 * Accepts: envelope
 *	    body
 */

void rfc822_encode_body_8bit (ENVELOPE *env,BODY *body)
{
  void *f;
  PART *part;
  PARAMETER **param;
  if (body) switch (body->type) {
  case TYPEMULTIPART:		/* multi-part */
    for (param = &body->parameter;
	 *param && strcmp ((*param)->attribute,"BOUNDARY");
	 param = &(*param)->next);
    if (!*param) {		/* cookie not set up yet? */
      char tmp[MAILTMPLEN];	/* make cookie not in BASE64 or QUOTEPRINT*/
      sprintf (tmp,"%ld-%ld-%ld=:%ld",(long) gethostid (),random (),time (0),
	       (long) getpid ());
      (*param) = mail_newbody_parameter ();
      (*param)->attribute = cpystr ("BOUNDARY");
      (*param)->value = cpystr (tmp);
    }
    part = body->nested.part;	/* encode body parts */
    do rfc822_encode_body_8bit (env,&part->body);
    while (part = part->next);	/* until done */
    break;
  case TYPEMESSAGE:		/* encapsulated message */
    switch (body->encoding) {
    case ENC7BIT:
    case ENC8BIT:
      break;
    case ENCBINARY:
      mm_log ("Binary included message in 8-bit message body",WARN);
      break;
    default:
      fatal ("Invalid rfc822_encode_body_7bit message encoding");
    }
    break;			/* can't change encoding */
  default:			/* other type, encode binary into BASE64 */
    if (body->encoding == ENCBINARY) {
				/* remember old binary contents */
      f = (void *) body->contents.text.data;
      body->contents.text.data =
	rfc822_binary ((void *) body->contents.text.data,
		       body->contents.text.size,&body->contents.text.size);
      body->encoding = ENCBASE64;
      fs_give (&f);		/* flush old binary contents */
    }
    break;
  }
}

/* Output RFC 822 body
 * Accepts: body
 *	    I/O routine
 *	    stream for I/O routine
 * Returns: T if successful, NIL if failure
 */

long rfc822_output_body (BODY *body,soutr_t f,void *s)
{
  PART *part;
  PARAMETER *param;
  char *cookie = NIL;
  char tmp[MAILTMPLEN];
  char *t;
  switch (body->type) {
  case TYPEMULTIPART:		/* multipart gets special handling */
    part = body->nested.part;	/* first body part */
				/* find cookie */
    for (param = body->parameter; param && !cookie; param = param->next)
      if (!strcmp (param->attribute,"BOUNDARY")) cookie = param->value;
    if (!cookie) cookie = "-";	/* yucky default */
    do {			/* for each part */
				/* build cookie */
      sprintf (t = tmp,"--%s\015\012",cookie);
				/* append mini-header */
      rfc822_write_body_header (&t,&part->body);
      strcat (t,"\015\012");	/* write terminating blank line */
				/* output cookie, mini-header, and contents */
      if (!((*f) (s,tmp) && rfc822_output_body (&part->body,f,s))) return NIL;
    } while (part = part->next);/* until done */
				/* output trailing cookie */
    sprintf (t = tmp,"--%s--",cookie);
    break;
  default:			/* all else is text now */
    t = (char *) body->contents.text.data;
    break;
  }
				/* output final stuff */
  if (t && *t && !((*f) (s,t) && (*f) (s,"\015\012"))) return NIL;
  return LONGT;
}

/* Convert BASE64 contents to binary
 * Accepts: source
 *	    length of source
 *	    pointer to return destination length
 * Returns: destination as binary or NIL if error
 */

void *rfc822_base64 (unsigned char *src,unsigned long srcl,unsigned long *len)
{
  char c;
  void *ret = fs_get ((size_t) (*len = 4 + ((srcl * 3) / 4)));
  char *d = (char *) ret;
  int e = 0;
  memset (ret,0,(size_t) *len);	/* initialize block */
  *len = 0;			/* in case we return an error */
  while (srcl--) {		/* until run out of characters */
    c = *src++;			/* simple-minded decode */
    if (isupper (c)) c -= 'A';
    else if (islower (c)) c -= 'a' - 26;
    else if (isdigit (c)) c -= '0' - 52;
    else if (c == '+') c = 62;
    else if (c == '/') c = 63;
    else if (c == '=') {	/* padding */
      switch (e++) {		/* check quantum position */
      case 3:
	e = 0;			/* restart quantum */
	break;
      case 2:
	if (*src == '=') break;
      default:			/* impossible quantum position */
	fs_give (&ret);
	return NIL;
      }
      continue;
    }
    else continue;		/* junk character */
    switch (e++) {		/* install based on quantum position */
    case 0:
      *d = c << 2;		/* byte 1: high 6 bits */
      break;
    case 1:
      *d++ |= c >> 4;		/* byte 1: low 2 bits */
      *d = c << 4;		/* byte 2: high 4 bits */
      break;
    case 2:
      *d++ |= c >> 2;		/* byte 2: low 4 bits */
      *d = c << 6;		/* byte 3: high 2 bits */
      break;
    case 3:
      *d++ |= c;		/* byte 3: low 6 bits */
      e = 0;			/* reinitialize mechanism */
      break;
    }
  }
  *len = d - (char *) ret;	/* calculate data length */
  return ret;			/* return the string */
}

/* Convert binary contents to BASE64
 * Accepts: source
 *	    length of source
 *	    pointer to return destination length
 * Returns: destination as BASE64
 */

unsigned char *rfc822_binary (void *src,unsigned long srcl,unsigned long *len)
{
  unsigned char *ret,*d;
  unsigned char *s = (unsigned char *) src;
  char *v = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  unsigned long i = ((srcl + 2) / 3) * 4;
  *len = i += 2 * ((i / 60) + 1);
  d = ret = (unsigned char *) fs_get ((size_t) ++i);
  for (i = 0; srcl; s += 3) {	/* process tuplets */
    *d++ = v[s[0] >> 2];	/* byte 1: high 6 bits (1) */
				/* byte 2: low 2 bits (1), high 4 bits (2) */
    *d++ = v[((s[0] << 4) + (--srcl ? (s[1] >> 4) : 0)) & 0x3f];
				/* byte 3: low 4 bits (2), high 2 bits (3) */
    *d++ = srcl ? v[((s[1] << 2) + (--srcl ? (s[2] >> 6) : 0)) & 0x3f] : '=';
				/* byte 4: low 6 bits (3) */
    *d++ = srcl ? v[s[2] & 0x3f] : '=';
    if (srcl) srcl--;		/* count third character if processed */
    if ((++i) == 15) {		/* output 60 characters? */
      i = 0;			/* restart line break count, insert CRLF */
      *d++ = '\015'; *d++ = '\012';
    }
  }
  *d++ = '\015'; *d++ = '\012';	/* insert final CRLF */
  *d = '\0';			/* tie off string */
  if (((unsigned long) (d - ret)) != *len) fatal ("rfc822_binary logic flaw");
  return ret;			/* return the resulting string */
}

/* Convert QUOTED-PRINTABLE contents to 8BIT
 * Accepts: source
 *	    length of source
 * 	    pointer to return destination length
 * Returns: destination as 8-bit text or NIL if error
 */

unsigned char *rfc822_qprint (unsigned char *src,unsigned long srcl,
			      unsigned long *len)
{
  unsigned char *ret = (unsigned char *) fs_get ((size_t) srcl + 1);
  unsigned char *d = ret;
  unsigned char *t = d;
  unsigned char *s = src;
  unsigned char c,e;
  *len = 0;			/* in case we return an error */
				/* until run out of characters */
  while (((unsigned long) (s - src)) < srcl) {
    switch (c = *s++) {		/* what type of character is it? */
    case '=':			/* quoting character */
      if (((unsigned long) (s - src)) < srcl) switch (c = *s++) {
      case '\0':		/* end of data */
	s--;			/* back up pointer */
	break;
      case '\015':		/* non-significant line break */
	t = d;			/* accept any leading spaces */
	if ((((unsigned long) (s - src)) < srcl) && (*s == '\012')) s++;
	break;
      default:			/* two hex digits then */
	if (!(isxdigit (c) && (((unsigned long) (s - src)) < srcl) &&
	      (e = *s++) && isxdigit (e))) {
	  fs_give ((void **) &ret);
	  return NIL;
	}
	if (isdigit (c)) c -= '0';
	else c -= (isupper (c) ? 'A' - 10 : 'a' - 10);
	if (isdigit (e)) e -= '0';
	else e -= (isupper (e) ? 'A' - 10 : 'a' - 10);
	*d++ = e + (c << 4);	/* merge the two hex digits */
	t = d;			/* note point of non-space */
	break;
      }
      break;
    case ' ':			/* space, possibly bogus */
      *d++ = c;			/* stash the space but don't update s */
      break;
    case '\015':		/* end of line */
      d = t;			/* slide back to last non-space, drop in */
    default:
      *d++ = c;			/* stash the character */
      t = d;			/* note point of non-space */
    }      
  }
  *d = '\0';			/* tie off results */
  *len = d - ret;		/* calculate length */
  return ret;			/* return the string */
}

/* Convert 8BIT contents to QUOTED-PRINTABLE
 * Accepts: source
 *	    length of source
 * 	    pointer to return destination length
 * Returns: destination as quoted-printable text
 */

#define MAXL (size_t) 75	/* 76th position only used by continuation = */

unsigned char *rfc822_8bit (unsigned char *src,unsigned long srcl,
			    unsigned long *len)
{
  unsigned long lp = 0;
  unsigned char *ret = (unsigned char *)
    fs_get ((size_t) (3*srcl + (6*srcl)/MAXL + 3));
  unsigned char *d = ret;
  char *hex = "0123456789ABCDEF";
  unsigned char c;
  while (srcl--) {		/* for each character */
				/* true line break? */
    if (((c = *src++) == '\015') && (*src == '\012') && srcl) {
      *d++ = '\015'; *d++ = *src++; srcl--;
      lp = 0;			/* reset line count */
    }
    else {			/* not a line break */
				/* quoting required? */
      if (iscntrl (c) || (c == 0x7f) || (c & 0x80) || (c == '=') ||
	  ((c == ' ') && (*src == '\015'))) {
	if ((lp += 3) > MAXL) {	/* yes, would line overflow? */
	  *d++ = '='; *d++ = '\015'; *d++ = '\012';
	  lp = 3;		/* set line count */
	}
	*d++ = '=';		/* quote character */
	*d++ = hex[c >> 4];	/* high order 4 bits */
	*d++ = hex[c & 0xf];	/* low order 4 bits */
      }
      else {			/* ordinary character */
	if ((++lp) > MAXL) {	/* would line overflow? */
	  *d++ = '='; *d++ = '\015'; *d++ = '\012';
	  lp = 1;		/* set line count */
	}
	*d++ = c;		/* ordinary character */
      }
    }
  }
  *d = '\0';			/* tie off destination */
  *len = d - ret;		/* calculate true size */
				/* try to give some space back */
  fs_resize ((void **) &ret,(size_t) *len + 1);
  return ret;
}