mutt / parse.c

/*
 * Copyright (C) 1996-2000,2012-2013 Michael R. Elkins <[e-mail]>
 * 
 *     This program 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 of the License, or
 *     (at your option) any later version.
 * 
 *     This program 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 this program; if not, write to the Free Software
 *     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */ 

#if HAVE_CONFIG_H
# include "config.h"
#endif

#include "mutt.h"
#include "mutt_regex.h"
#include "mailbox.h"
#include "mime.h"
#include "rfc2047.h"
#include "rfc2231.h"
#include "mutt_crypt.h"
#include "url.h"

#include <string.h>
#include <ctype.h>
#include <sys/stat.h>
#include <stdlib.h>

/* Reads an arbitrarily long header field, and looks ahead for continuation
 * lines.  ``line'' must point to a dynamically allocated string; it is
 * increased if more space is required to fit the whole line.
 */
char *mutt_read_rfc822_line (FILE *f, char *line, size_t *linelen)
{
  char *buf = line;
  int ch;
  size_t offset = 0;
  size_t len = 0;

  FOREVER
  {
    if (fgets (buf, *linelen - offset, f) == NULL ||	/* end of file or */
	(ISSPACE (*line) && !offset))			/* end of headers */ 
    {
      *line = 0;
      return (line);
    }

    len = mutt_strlen (buf);
    if (! len)
      return (line);

    buf += len - 1;
    if (*buf == '\n')
    {
      /* we did get a full line. remove trailing space */
      while (ISSPACE (*buf))
	*buf-- = 0;	/* we cannot come beyond line's beginning because
			 * it begins with a non-space */

      /* check to see if the next line is a continuation line */
      if ((ch = fgetc (f)) != ' ' && ch != '\t')
      {
	ungetc (ch, f);
	return (line); /* next line is a separate header field or EOH */
      }

      /* eat tabs and spaces from the beginning of the continuation line */
      while ((ch = fgetc (f)) == ' ' || ch == '\t')
	;
      ungetc (ch, f);
      *++buf = ' '; /* string is still terminated because we removed
		       at least one whitespace char above */
    }

    buf++;
    offset = buf - line;
    if (*linelen < offset + STRING)
    {
      /* grow the buffer */
      *linelen += STRING;
      safe_realloc (&line, *linelen);
      buf = line + offset;
    }
  }
  /* not reached */
}

static LIST *mutt_parse_references (char *s, int in_reply_to)
{
  LIST *t, *lst = NULL;
  char *m;
  const char *sp;

  m = mutt_extract_message_id (s, &sp);
  while (m)
  {
    t = safe_malloc (sizeof (LIST));
    t->data = m;
    t->next = lst;
    lst = t;

    m = mutt_extract_message_id (NULL, &sp);
  }

  return lst;
}

int mutt_check_encoding (const char *c)
{
  if (ascii_strncasecmp ("7bit", c, sizeof ("7bit")-1) == 0)
    return (ENC7BIT);
  else if (ascii_strncasecmp ("8bit", c, sizeof ("8bit")-1) == 0)
    return (ENC8BIT);
  else if (ascii_strncasecmp ("binary", c, sizeof ("binary")-1) == 0)
    return (ENCBINARY);
  else if (ascii_strncasecmp ("quoted-printable", c, sizeof ("quoted-printable")-1) == 0)
    return (ENCQUOTEDPRINTABLE);
  else if (ascii_strncasecmp ("base64", c, sizeof("base64")-1) == 0)
    return (ENCBASE64);
  else if (ascii_strncasecmp ("x-uuencode", c, sizeof("x-uuencode")-1) == 0)
    return (ENCUUENCODED);
#ifdef SUN_ATTACHMENT
  else if (ascii_strncasecmp ("uuencode", c, sizeof("uuencode")-1) == 0)
    return (ENCUUENCODED);
#endif
  else
    return (ENCOTHER);
}

static PARAMETER *parse_parameters (const char *s)
{
  PARAMETER *head = 0, *cur = 0, *new;
  char buffer[LONG_STRING];
  const char *p;
  size_t i;

  dprint (2, (debugfile, "parse_parameters: `%s'\n", s));
  
  while (*s)
  {
    if ((p = strpbrk (s, "=;")) == NULL)
    {
      dprint(1, (debugfile, "parse_parameters: malformed parameter: %s\n", s));
      goto bail;
    }

    /* if we hit a ; now the parameter has no value, just skip it */
    if (*p != ';')
    {
      i = p - s;
      /* remove whitespace from the end of the attribute name */
      while (i > 0 && is_email_wsp(s[i-1]))
	--i;

      /* the check for the missing parameter token is here so that we can skip
       * over any quoted value that may be present.
       */
      if (i == 0)
      {
	dprint(1, (debugfile, "parse_parameters: missing attribute: %s\n", s));
	new = NULL;
      }
      else
      {
	new = mutt_new_parameter ();
	new->attribute = mutt_substrdup(s, s + i);
      }

      s = skip_email_wsp(p + 1); /* skip over the = */

      if (*s == '"')
      {
        int state_ascii = 1;
	s++;
	for (i=0; *s && i < sizeof (buffer) - 1; i++, s++)
	{
	  if (AssumedCharset && *AssumedCharset) {
            /* As iso-2022-* has a character of '"' with non-ascii state,
	     * ignore it. */
            if (*s == 0x1b && i < sizeof (buffer) - 2)
            {
              if (s[1] == '(' && (s[2] == 'B' || s[2] == 'J'))
                state_ascii = 1;
              else
                state_ascii = 0;
            }
          }
          if (state_ascii && *s == '"')
            break;
	  if (*s == '\\')
	  {
	    /* Quote the next character */
	    buffer[i] = s[1];
	    if (!*++s)
	      break;
	  }
	  else
	    buffer[i] = *s;
	}
	buffer[i] = 0;
	if (*s)
	  s++; /* skip over the " */
      }
      else
      {
	for (i=0; *s && *s != ' ' && *s != ';' && i < sizeof (buffer) - 1; i++, s++)
	  buffer[i] = *s;
	buffer[i] = 0;
      }

      /* if the attribute token was missing, 'new' will be NULL */
      if (new)
      {
	new->value = safe_strdup (buffer);

	dprint (2, (debugfile, "parse_parameter: `%s' = `%s'\n",
	      new->attribute ? new->attribute : "",
	      new->value ? new->value : ""));

	/* Add this parameter to the list */
	if (head)
	{
	  cur->next = new;
	  cur = cur->next;
	}
	else
	  head = cur = new;
      }
    }
    else
    {
      dprint (1, (debugfile, "parse_parameters(): parameter with no value: %s\n", s));
      s = p;
    }

    /* Find the next parameter */
    if (*s != ';' && (s = strchr (s, ';')) == NULL)
      break; /* no more parameters */

    do
    {
      /* Move past any leading whitespace. the +1 skips over the semicolon */
      s = skip_email_wsp(s + 1);
    }
    while (*s == ';'); /* skip empty parameters */
  }    

bail:

  rfc2231_decode_parameters (&head);
  return (head);
}

int mutt_check_mime_type (const char *s)
{
  if (ascii_strcasecmp ("text", s) == 0)
    return TYPETEXT;
  else if (ascii_strcasecmp ("multipart", s) == 0)
    return TYPEMULTIPART;
#ifdef SUN_ATTACHMENT 
  else if (ascii_strcasecmp ("x-sun-attachment", s) == 0)
    return TYPEMULTIPART;
#endif
  else if (ascii_strcasecmp ("application", s) == 0)
    return TYPEAPPLICATION;
  else if (ascii_strcasecmp ("message", s) == 0)
    return TYPEMESSAGE;
  else if (ascii_strcasecmp ("image", s) == 0)
    return TYPEIMAGE;
  else if (ascii_strcasecmp ("audio", s) == 0)
    return TYPEAUDIO;
  else if (ascii_strcasecmp ("video", s) == 0)
    return TYPEVIDEO;
  else if (ascii_strcasecmp ("model", s) == 0)
    return TYPEMODEL;
  else if (ascii_strcasecmp ("*", s) == 0)
    return TYPEANY;
  else if (ascii_strcasecmp (".*", s) == 0)
    return TYPEANY;
  else
    return TYPEOTHER;
}

void mutt_parse_content_type (char *s, BODY *ct)
{
  char *pc;
  char *subtype;

  FREE (&ct->subtype);
  mutt_free_parameter(&ct->parameter);

  /* First extract any existing parameters */
  if ((pc = strchr(s, ';')) != NULL)
  {
    *pc++ = 0;
    while (*pc && ISSPACE (*pc))
      pc++;
    ct->parameter = parse_parameters(pc);

    /* Some pre-RFC1521 gateways still use the "name=filename" convention,
     * but if a filename has already been set in the content-disposition,
     * let that take precedence, and don't set it here */
    if ((pc = mutt_get_parameter( "name", ct->parameter)) && !ct->filename)
      ct->filename = safe_strdup(pc);
    
#ifdef SUN_ATTACHMENT
    /* this is deep and utter perversion */
    if ((pc = mutt_get_parameter ("conversions", ct->parameter)))
      ct->encoding = mutt_check_encoding (pc);
#endif
    
  }
  
  /* Now get the subtype */
  if ((subtype = strchr(s, '/')))
  {
    *subtype++ = '\0';
    for(pc = subtype; *pc && !ISSPACE(*pc) && *pc != ';'; pc++)
      ;
    *pc = '\0';
    ct->subtype = safe_strdup (subtype);
  }

  /* Finally, get the major type */
  ct->type = mutt_check_mime_type (s);

#ifdef SUN_ATTACHMENT
  if (ascii_strcasecmp ("x-sun-attachment", s) == 0)
      ct->subtype = safe_strdup ("x-sun-attachment");
#endif

  if (ct->type == TYPEOTHER)
  {
    ct->xtype = safe_strdup (s);
  }

  if (ct->subtype == NULL)
  {
    /* Some older non-MIME mailers (i.e., mailtool, elm) have a content-type
     * field, so we can attempt to convert the type to BODY here.
     */
    if (ct->type == TYPETEXT)
      ct->subtype = safe_strdup ("plain");
    else if (ct->type == TYPEAUDIO)
      ct->subtype = safe_strdup ("basic");
    else if (ct->type == TYPEMESSAGE)
      ct->subtype = safe_strdup ("rfc822");
    else if (ct->type == TYPEOTHER)
    {
      char buffer[SHORT_STRING];

      ct->type = TYPEAPPLICATION;
      snprintf (buffer, sizeof (buffer), "x-%s", s);
      ct->subtype = safe_strdup (buffer);
    }
    else
      ct->subtype = safe_strdup ("x-unknown");
  }

  /* Default character set for text types. */
  if (ct->type == TYPETEXT)
  {
    if (!(pc = mutt_get_parameter ("charset", ct->parameter)))
      mutt_set_parameter ("charset", (AssumedCharset && *AssumedCharset) ?
                         (const char *) mutt_get_default_charset ()
                         : "us-ascii", &ct->parameter);
  }

}

static void parse_content_disposition (const char *s, BODY *ct)
{
  PARAMETER *parms;

  if (!ascii_strncasecmp ("inline", s, 6))
    ct->disposition = DISPINLINE;
  else if (!ascii_strncasecmp ("form-data", s, 9))
    ct->disposition = DISPFORMDATA;
  else
    ct->disposition = DISPATTACH;

  /* Check to see if a default filename was given */
  if ((s = strchr (s, ';')) != NULL)
  {
    s = skip_email_wsp(s + 1);
    if ((s = mutt_get_parameter ("filename", (parms = parse_parameters (s)))))
      mutt_str_replace (&ct->filename, s);
    if ((s = mutt_get_parameter ("name", parms)))
      ct->form_name = safe_strdup (s);
    mutt_free_parameter (&parms);
  }
}

/* args:
 *	fp	stream to read from
 *
 *	digest	1 if reading subparts of a multipart/digest, 0
 *		otherwise
 */

BODY *mutt_read_mime_header (FILE *fp, int digest)
{
  BODY *p = mutt_new_body();
  char *c;
  char *line = safe_malloc (LONG_STRING);
  size_t linelen = LONG_STRING;
  
  p->hdr_offset  = ftello (fp);

  p->encoding    = ENC7BIT; /* default from RFC1521 */
  p->type        = digest ? TYPEMESSAGE : TYPETEXT;
  p->disposition = DISPINLINE;
  
  while (*(line = mutt_read_rfc822_line (fp, line, &linelen)) != 0)
  {
    /* Find the value of the current header */
    if ((c = strchr (line, ':')))
    {
      *c = 0;
      c = skip_email_wsp(c + 1);
      if (!*c)
      {
	dprint (1, (debugfile, "mutt_read_mime_header(): skipping empty header field: %s\n", line));
	continue;
      }
    }
    else
    {
      dprint (1, (debugfile, "read_mime_header: bogus MIME header: %s\n", line));
      break;
    }

    if (!ascii_strncasecmp ("content-", line, 8))
    {
      if (!ascii_strcasecmp ("type", line + 8))
	mutt_parse_content_type (c, p);
      else if (!ascii_strcasecmp ("transfer-encoding", line + 8))
	p->encoding = mutt_check_encoding (c);
      else if (!ascii_strcasecmp ("disposition", line + 8))
	parse_content_disposition (c, p);
      else if (!ascii_strcasecmp ("description", line + 8))
      {
	mutt_str_replace (&p->description, c);
	rfc2047_decode (&p->description);
      }
    } 
#ifdef SUN_ATTACHMENT
    else if (!ascii_strncasecmp ("x-sun-", line, 6))
    {
      if (!ascii_strcasecmp ("data-type", line + 6))
        mutt_parse_content_type (c, p);
      else if (!ascii_strcasecmp ("encoding-info", line + 6))
        p->encoding = mutt_check_encoding (c);
      else if (!ascii_strcasecmp ("content-lines", line + 6))
        mutt_set_parameter ("content-lines", c, &(p->parameter));
      else if (!ascii_strcasecmp ("data-description", line + 6))
      {
	mutt_str_replace (&p->description, c);
        rfc2047_decode (&p->description);
      }
    }
#endif
  }
  p->offset = ftello (fp); /* Mark the start of the real data */
  if (p->type == TYPETEXT && !p->subtype)
    p->subtype = safe_strdup ("plain");
  else if (p->type == TYPEMESSAGE && !p->subtype)
    p->subtype = safe_strdup ("rfc822");

  FREE (&line);

  return (p);
}

void mutt_parse_part (FILE *fp, BODY *b)
{
  char *bound = 0;

  switch (b->type)
  {
    case TYPEMULTIPART:
#ifdef SUN_ATTACHMENT
      if ( !ascii_strcasecmp (b->subtype, "x-sun-attachment") )
          bound = "--------";
      else
#endif
          bound = mutt_get_parameter ("boundary", b->parameter);

      fseeko (fp, b->offset, SEEK_SET);
      b->parts =  mutt_parse_multipart (fp, bound, 
					b->offset + b->length,
					ascii_strcasecmp ("digest", b->subtype) == 0);
      break;

    case TYPEMESSAGE:
      if (b->subtype)
      {
	fseeko (fp, b->offset, SEEK_SET);
	if (mutt_is_message_type(b->type, b->subtype))
	  b->parts = mutt_parse_messageRFC822 (fp, b);
	else if (ascii_strcasecmp (b->subtype, "external-body") == 0)
	  b->parts = mutt_read_mime_header (fp, 0);
	else
	  return;
      }
      break;

    default:
      return;
  }

  /* try to recover from parsing error */
  if (!b->parts)
  {
    b->type = TYPETEXT;
    mutt_str_replace (&b->subtype, "plain");
  }
}

/* parse a MESSAGE/RFC822 body
 *
 * args:
 *	fp		stream to read from
 *
 *	parent		structure which contains info about the message/rfc822
 *			body part
 *
 * NOTE: this assumes that `parent->length' has been set!
 */

BODY *mutt_parse_messageRFC822 (FILE *fp, BODY *parent)
{
  BODY *msg;

  parent->hdr = mutt_new_header ();
  parent->hdr->offset = ftello (fp);
  parent->hdr->env = mutt_read_rfc822_header (fp, parent->hdr, 0, 0);
  msg = parent->hdr->content;

  /* ignore the length given in the content-length since it could be wrong
     and we already have the info to calculate the correct length */
  /* if (msg->length == -1) */
  msg->length = parent->length - (msg->offset - parent->offset);

  /* if body of this message is empty, we can end up with a negative length */
  if (msg->length < 0)
    msg->length = 0;

  mutt_parse_part(fp, msg);
  return (msg);
}

/* parse a multipart structure
 *
 * args:
 *	fp		stream to read from
 *
 *	boundary	body separator
 *
 *	end_off		length of the multipart body (used when the final
 *			boundary is missing to avoid reading too far)
 *
 *	digest		1 if reading a multipart/digest, 0 otherwise
 */

BODY *mutt_parse_multipart (FILE *fp, const char *boundary, LOFF_T end_off, int digest)
{
#ifdef SUN_ATTACHMENT
  int lines;
#endif
  int blen, len, crlf = 0;
  char buffer[LONG_STRING];
  BODY *head = 0, *last = 0, *new = 0;
  int i;
  int final = 0; /* did we see the ending boundary? */

  if (!boundary)
  {
    mutt_error _("multipart message has no boundary parameter!");
    return (NULL);
  }

  blen = mutt_strlen (boundary);
  while (ftello (fp) < end_off && fgets (buffer, LONG_STRING, fp) != NULL)
  {
    len = mutt_strlen (buffer);

    crlf =  (len > 1 && buffer[len - 2] == '\r') ? 1 : 0;

    if (buffer[0] == '-' && buffer[1] == '-' &&
	mutt_strncmp (buffer + 2, boundary, blen) == 0)
    {
      if (last)
      {
	last->length = ftello (fp) - last->offset - len - 1 - crlf;
	if (last->parts && last->parts->length == 0)
	  last->parts->length = ftello (fp) - last->parts->offset - len - 1 - crlf;
	/* if the body is empty, we can end up with a -1 length */
	if (last->length < 0)
	  last->length = 0;
      }

      /* Remove any trailing whitespace, up to the length of the boundary */
      for (i = len - 1; ISSPACE (buffer[i]) && i >= blen + 2; i--)
        buffer[i] = 0;

      /* Check for the end boundary */
      if (mutt_strcmp (buffer + blen + 2, "--") == 0)
      {
	final = 1;
	break; /* done parsing */
      }
      else if (buffer[2 + blen] == 0)
      {
	new = mutt_read_mime_header (fp, digest);

#ifdef SUN_ATTACHMENT
        if (mutt_get_parameter ("content-lines", new->parameter)) {
	  mutt_atoi (mutt_get_parameter ("content-lines", new->parameter), &lines);
	  for ( ; lines; lines-- )
	     if (ftello (fp) >= end_off || fgets (buffer, LONG_STRING, fp) == NULL)
	       break;
	}
#endif
	
	/*
	 * Consistency checking - catch
	 * bad attachment end boundaries
	 */
	
	if(new->offset > end_off)
	{
	  mutt_free_body(&new);
	  break;
	}
	if (head)
	{
	  last->next = new;
	  last = new;
	}
	else
	  last = head = new;
      }
    }
  }

  /* in case of missing end boundary, set the length to something reasonable */
  if (last && last->length == 0 && !final)
    last->length = end_off - last->offset;

  /* parse recursive MIME parts */
  for(last = head; last; last = last->next)
    mutt_parse_part(fp, last);
  
  return (head);
}

static const char *uncomment_timezone (char *buf, size_t buflen, const char *tz)
{
  char *p;
  size_t len;

  if (*tz != '(')
    return tz; /* no need to do anything */
  tz = skip_email_wsp(tz + 1);
  if ((p = strpbrk (tz, " )")) == NULL)
    return tz;
  len = p - tz;
  if (len > buflen - 1)
    len = buflen - 1;
  memcpy (buf, tz, len);
  buf[len] = 0;
  return buf;
}

static const struct tz_t
{
  char tzname[5];
  unsigned char zhours;
  unsigned char zminutes;
  unsigned char zoccident; /* west of UTC? */
}
TimeZones[] =
{
  { "aat",   1,  0, 1 }, /* Atlantic Africa Time */
  { "adt",   4,  0, 0 }, /* Arabia DST */
  { "ast",   3,  0, 0 }, /* Arabia */
/*{ "ast",   4,  0, 1 },*/ /* Atlantic */
  { "bst",   1,  0, 0 }, /* British DST */
  { "cat",   1,  0, 0 }, /* Central Africa */
  { "cdt",   5,  0, 1 },
  { "cest",  2,  0, 0 }, /* Central Europe DST */
  { "cet",   1,  0, 0 }, /* Central Europe */
  { "cst",   6,  0, 1 },
/*{ "cst",   8,  0, 0 },*/ /* China */
/*{ "cst",   9, 30, 0 },*/ /* Australian Central Standard Time */
  { "eat",   3,  0, 0 }, /* East Africa */
  { "edt",   4,  0, 1 },
  { "eest",  3,  0, 0 }, /* Eastern Europe DST */
  { "eet",   2,  0, 0 }, /* Eastern Europe */
  { "egst",  0,  0, 0 }, /* Eastern Greenland DST */
  { "egt",   1,  0, 1 }, /* Eastern Greenland */
  { "est",   5,  0, 1 },
  { "gmt",   0,  0, 0 },
  { "gst",   4,  0, 0 }, /* Presian Gulf */
  { "hkt",   8,  0, 0 }, /* Hong Kong */
  { "ict",   7,  0, 0 }, /* Indochina */
  { "idt",   3,  0, 0 }, /* Israel DST */
  { "ist",   2,  0, 0 }, /* Israel */
/*{ "ist",   5, 30, 0 },*/ /* India */
  { "jst",   9,  0, 0 }, /* Japan */
  { "kst",   9,  0, 0 }, /* Korea */
  { "mdt",   6,  0, 1 },
  { "met",   1,  0, 0 }, /* this is now officially CET */
  { "msd",   4,  0, 0 }, /* Moscow DST */
  { "msk",   3,  0, 0 }, /* Moscow */
  { "mst",   7,  0, 1 },
  { "nzdt", 13,  0, 0 }, /* New Zealand DST */
  { "nzst", 12,  0, 0 }, /* New Zealand */
  { "pdt",   7,  0, 1 },
  { "pst",   8,  0, 1 },
  { "sat",   2,  0, 0 }, /* South Africa */
  { "smt",   4,  0, 0 }, /* Seychelles */
  { "sst",  11,  0, 1 }, /* Samoa */
/*{ "sst",   8,  0, 0 },*/ /* Singapore */
  { "utc",   0,  0, 0 },
  { "wat",   0,  0, 0 }, /* West Africa */
  { "west",  1,  0, 0 }, /* Western Europe DST */
  { "wet",   0,  0, 0 }, /* Western Europe */
  { "wgst",  2,  0, 1 }, /* Western Greenland DST */
  { "wgt",   3,  0, 1 }, /* Western Greenland */
  { "wst",   8,  0, 0 }, /* Western Australia */
};

/* parses a date string in RFC822 format:
 *
 * Date: [ weekday , ] day-of-month month year hour:minute:second timezone
 *
 * This routine assumes that `h' has been initialized to 0.  the `timezone'
 * field is optional, defaulting to +0000 if missing.
 */
time_t mutt_parse_date (const char *s, HEADER *h)
{
  int count = 0;
  char *t;
  int hour, min, sec;
  struct tm tm;
  int i;
  int tz_offset = 0;
  int zhours = 0;
  int zminutes = 0;
  int zoccident = 0;
  const char *ptz;
  char tzstr[SHORT_STRING];
  char scratch[SHORT_STRING];

  /* Don't modify our argument. Fixed-size buffer is ok here since
   * the date format imposes a natural limit. 
   */

  strfcpy (scratch, s, sizeof (scratch));
  
  /* kill the day of the week, if it exists. */
  if ((t = strchr (scratch, ',')))
    t++;
  else
    t = scratch;
  t = skip_email_wsp(t);

  memset (&tm, 0, sizeof (tm));

  while ((t = strtok (t, " \t")) != NULL)
  {
    switch (count)
    {
      case 0: /* day of the month */
	if (mutt_atoi (t, &tm.tm_mday) < 0 || tm.tm_mday < 0)
	  return (-1);
	if (tm.tm_mday > 31)
	  return (-1);
	break;

      case 1: /* month of the year */
	if ((i = mutt_check_month (t)) < 0)
	  return (-1);
	tm.tm_mon = i;
	break;

      case 2: /* year */
	if (mutt_atoi (t, &tm.tm_year) < 0 || tm.tm_year < 0)
	  return (-1);
        if (tm.tm_year < 50)
	  tm.tm_year += 100;
        else if (tm.tm_year >= 1900)
	  tm.tm_year -= 1900;
	break;

      case 3: /* time of day */
	if (sscanf (t, "%d:%d:%d", &hour, &min, &sec) == 3)
	  ;
	else if (sscanf (t, "%d:%d", &hour, &min) == 2)
	  sec = 0;
	else
	{
	  dprint(1, (debugfile, "parse_date: could not process time format: %s\n", t));
	  return(-1);
	}
	tm.tm_hour = hour;
	tm.tm_min = min;
	tm.tm_sec = sec;
	break;

      case 4: /* timezone */
	/* sometimes we see things like (MST) or (-0700) so attempt to
	 * compensate by uncommenting the string if non-RFC822 compliant
	 */
	ptz = uncomment_timezone (tzstr, sizeof (tzstr), t);

	if (*ptz == '+' || *ptz == '-')
	{
	  if (ptz[1] && ptz[2] && ptz[3] && ptz[4]
	      && isdigit ((unsigned char) ptz[1]) && isdigit ((unsigned char) ptz[2])
	      && isdigit ((unsigned char) ptz[3]) && isdigit ((unsigned char) ptz[4]))
	  {
	    zhours = (ptz[1] - '0') * 10 + (ptz[2] - '0');
	    zminutes = (ptz[3] - '0') * 10 + (ptz[4] - '0');

	    if (ptz[0] == '-')
	      zoccident = 1;
	  }
	}
	else
	{
	  struct tz_t *tz;

	  tz = bsearch (ptz, TimeZones, sizeof TimeZones/sizeof (struct tz_t),
			sizeof (struct tz_t),
			(int (*)(const void *, const void *)) ascii_strcasecmp
			/* This is safe to do: A pointer to a struct equals
			 * a pointer to its first element*/);

	  if (tz)
	  {
	    zhours = tz->zhours;
	    zminutes = tz->zminutes;
	    zoccident = tz->zoccident;
	  }

	  /* ad hoc support for the European MET (now officially CET) TZ */
	  if (ascii_strcasecmp (t, "MET") == 0)
	  {
	    if ((t = strtok (NULL, " \t")) != NULL)
	    {
	      if (!ascii_strcasecmp (t, "DST"))
		zhours++;
	    }
	  }
	}
	tz_offset = zhours * 3600 + zminutes * 60;
	if (!zoccident)
	  tz_offset = -tz_offset;
	break;
    }
    count++;
    t = 0;
  }

  if (count < 4) /* don't check for missing timezone */
  {
    dprint(1,(debugfile, "parse_date(): error parsing date format, using received time\n"));
    return (-1);
  }

  if (h)
  {
    h->zhours = zhours;
    h->zminutes = zminutes;
    h->zoccident = zoccident;
  }

  return (mutt_mktime (&tm, 0) + tz_offset);
}

/* extract the first substring that looks like a message-id.
 * call back with NULL for more (like strtok).
 */
char *mutt_extract_message_id (const char *s, const char **saveptr)
{
  const char *o, *onull, *p;
  char *ret = NULL;

  if (s)
    p = s;
  else if (saveptr)
    p = *saveptr;
  else
    return NULL;

  for (s = NULL, o = NULL, onull = NULL;
       (p = strpbrk (p, "<> \t;")) != NULL; ++p)
  {
    if (*p == '<')
    {
      s = p; 
      o = onull = NULL;
      continue;
    }

    if (!s)
      continue;

    if (*p == '>')
    {
      size_t olen = onull - o, slen = p - s + 1;
      ret = safe_malloc (olen + slen + 1);
      if (o)
	memcpy (ret, o, olen);
      memcpy (ret + olen, s, slen);
      ret[olen + slen] = '\0';
      if (saveptr)
	*saveptr = p + 1; /* next call starts after '>' */
      return ret;
    }

    /* some idiotic clients break their message-ids between lines */
    if (s == p) 
      /* step past another whitespace */
      s = p + 1;
    else if (o)
      /* more than two lines, give up */
      s = o = onull = NULL;
    else
    {
      /* remember the first line, start looking for the second */
      o = s;
      onull = p;
      s = p + 1;
    }
  }

  return NULL;
}

void mutt_parse_mime_message (CONTEXT *ctx, HEADER *cur)
{
  MESSAGE *msg;

  do {
    if (cur->content->type != TYPEMESSAGE &&
        cur->content->type != TYPEMULTIPART)
      break; /* nothing to do */

    if (cur->content->parts)
      break; /* The message was parsed earlier. */

    if ((msg = mx_open_message (ctx, cur->msgno)))
    {
      mutt_parse_part (msg->fp, cur->content);

      if (WithCrypto)
        cur->security = crypt_query (cur->content);

      mx_close_message (ctx, &msg);
    }
  } while (0);

  cur->attach_valid = 0;
}

int mutt_parse_rfc822_line (ENVELOPE *e, HEADER *hdr, char *line, char *p, short user_hdrs, short weed,
			    short do_2047, LIST **lastp)
{
  int matched = 0;
  LIST *last = NULL;
  
  if (lastp)
    last = *lastp;
  
  switch (ascii_tolower (line[0]))
  {
    case 'a':
    if (ascii_strcasecmp (line+1, "pparently-to") == 0)
    {
      e->to = rfc822_parse_adrlist (e->to, p);
      matched = 1;
    }
    else if (ascii_strcasecmp (line+1, "pparently-from") == 0)
    {
      e->from = rfc822_parse_adrlist (e->from, p);
      matched = 1;
    }
    break;
    
    case 'b':
    if (ascii_strcasecmp (line+1, "cc") == 0)
    {
      e->bcc = rfc822_parse_adrlist (e->bcc, p);
      matched = 1;
    }
    break;
    
    case 'c':
    if (ascii_strcasecmp (line+1, "c") == 0)
    {
      e->cc = rfc822_parse_adrlist (e->cc, p);
      matched = 1;
    }
    else if (ascii_strncasecmp (line + 1, "ontent-", 7) == 0)
    {
      if (ascii_strcasecmp (line+8, "type") == 0)
      {
	if (hdr)
	  mutt_parse_content_type (p, hdr->content);
	matched = 1;
      }
      else if (ascii_strcasecmp (line+8, "transfer-encoding") == 0)
      {
	if (hdr)
	  hdr->content->encoding = mutt_check_encoding (p);
	matched = 1;
      }
      else if (ascii_strcasecmp (line+8, "length") == 0)
      {
	if (hdr)
	{
	  if ((hdr->content->length = atol (p)) < 0)
	    hdr->content->length = -1;
	}
	matched = 1;
      }
      else if (ascii_strcasecmp (line+8, "description") == 0)
      {
	if (hdr)
	{
	  mutt_str_replace (&hdr->content->description, p);
	  rfc2047_decode (&hdr->content->description);
	}
	matched = 1;
      }
      else if (ascii_strcasecmp (line+8, "disposition") == 0)
      {
	if (hdr)
	  parse_content_disposition (p, hdr->content);
	matched = 1;
      }
    }
    break;
    
    case 'd':
    if (!ascii_strcasecmp ("ate", line + 1))
    {
      mutt_str_replace (&e->date, p);
      if (hdr)
	hdr->date_sent = mutt_parse_date (p, hdr);
      matched = 1;
    }
    break;
    
    case 'e':
    if (!ascii_strcasecmp ("xpires", line + 1) &&
	hdr && mutt_parse_date (p, NULL) < time (NULL))
      hdr->expired = 1;
    break;
    
    case 'f':
    if (!ascii_strcasecmp ("rom", line + 1))
    {
      e->from = rfc822_parse_adrlist (e->from, p);
      matched = 1;
    }
    break;
    
    case 'i':
    if (!ascii_strcasecmp (line+1, "n-reply-to"))
    {
      mutt_free_list (&e->in_reply_to);
      e->in_reply_to = mutt_parse_references (p, 1);
      matched = 1;
    }
    break;
    
    case 'l':
    if (!ascii_strcasecmp (line + 1, "ines"))
    {
      if (hdr)
      {
	/* 
	 * HACK - mutt has, for a very short time, produced negative
	 * Lines header values.  Ignore them. 
	 */
	if (mutt_atoi (p, &hdr->lines) < 0 || hdr->lines < 0)
	  hdr->lines = 0;
      }

      matched = 1;
    }
    else if (!ascii_strcasecmp (line + 1, "ist-Post"))
    {
      /* RFC 2369.  FIXME: We should ignore whitespace, but don't. */
      if (strncmp (p, "NO", 2))
      {
	char *beg, *end;
	for (beg = strchr (p, '<'); beg; beg = strchr (end, ','))
	{
	  ++beg;
	  if (!(end = strchr (beg, '>')))
	    break;
	  
	  /* Take the first mailto URL */
	  if (url_check_scheme (beg) == U_MAILTO)
	  {
	    FREE (&e->list_post);
	    e->list_post = mutt_substrdup (beg, end);
	    break;
	  }
	}
      }
      matched = 1;
    }
    break;
    
    case 'm':
    if (!ascii_strcasecmp (line + 1, "ime-version"))
    {
      if (hdr)
	hdr->mime = 1;
      matched = 1;
    }
    else if (!ascii_strcasecmp (line + 1, "essage-id"))
    {
      /* We add a new "Message-ID:" when building a message */
      FREE (&e->message_id);
      e->message_id = mutt_extract_message_id (p, NULL);
      matched = 1;
    }
    else if (!ascii_strncasecmp (line + 1, "ail-", 4))
    {
      if (!ascii_strcasecmp (line + 5, "reply-to"))
      {
	/* override the Reply-To: field */
	rfc822_free_address (&e->reply_to);
	e->reply_to = rfc822_parse_adrlist (e->reply_to, p);
	matched = 1;
      }
      else if (!ascii_strcasecmp (line + 5, "followup-to"))
      {
	e->mail_followup_to = rfc822_parse_adrlist (e->mail_followup_to, p);
	matched = 1;
      }
    }
    break;
    
    case 'r':
    if (!ascii_strcasecmp (line + 1, "eferences"))
    {
      mutt_free_list (&e->references);
      e->references = mutt_parse_references (p, 0);
      matched = 1;
    }
    else if (!ascii_strcasecmp (line + 1, "eply-to"))
    {
      e->reply_to = rfc822_parse_adrlist (e->reply_to, p);
      matched = 1;
    }
    else if (!ascii_strcasecmp (line + 1, "eturn-path"))
    {
      e->return_path = rfc822_parse_adrlist (e->return_path, p);
      matched = 1;
    }
    else if (!ascii_strcasecmp (line + 1, "eceived"))
    {
      if (hdr && !hdr->received)
      {
	char *d = strrchr (p, ';');
	
	if (d)
	  hdr->received = mutt_parse_date (d + 1, NULL);
      }
    }
    break;
    
    case 's':
    if (!ascii_strcasecmp (line + 1, "ubject"))
    {
      if (!e->subject)
	e->subject = safe_strdup (p);
      matched = 1;
    }
    else if (!ascii_strcasecmp (line + 1, "ender"))
    {
      e->sender = rfc822_parse_adrlist (e->sender, p);
      matched = 1;
    }
    else if (!ascii_strcasecmp (line + 1, "tatus"))
    {
      if (hdr)
      {
	while (*p)
	{
	  switch(*p)
	  {
	    case 'r':
	    hdr->replied = 1;
	    break;
	    case 'O':
	      hdr->old = 1;
	    break;
	    case 'R':
	    hdr->read = 1;
	    break;
	  }
	  p++;
	}
      }
      matched = 1;
    }
    else if ((!ascii_strcasecmp ("upersedes", line + 1) ||
	      !ascii_strcasecmp ("upercedes", line + 1)) && hdr)
    {
      FREE(&e->supersedes);
      e->supersedes = safe_strdup (p);
    }
    break;
    
    case 't':
    if (ascii_strcasecmp (line+1, "o") == 0)
    {
      e->to = rfc822_parse_adrlist (e->to, p);
      matched = 1;
    }
    break;
    
    case 'x':
    if (ascii_strcasecmp (line+1, "-status") == 0)
    {
      if (hdr)
      {
	while (*p)
	{
	  switch (*p)
	  {
	    case 'A':
	    hdr->replied = 1;
	    break;
	    case 'D':
	    hdr->deleted = 1;
	    break;
	    case 'F':
	    hdr->flagged = 1;
	    break;
	    default:
	    break;
	  }
	  p++;
	}
      }
      matched = 1;
    }
    else if (ascii_strcasecmp (line+1, "-label") == 0)
    {
      FREE(&e->x_label);
      e->x_label = safe_strdup(p);
      matched = 1;
    }
    
    default:
    break;
  }
  
  /* Keep track of the user-defined headers */
  if (!matched && user_hdrs)
  {
    /* restore the original line */
    line[strlen (line)] = ':';
    
    if (weed && option (OPTWEED) && mutt_matches_ignore (line, Ignore)
	&& !mutt_matches_ignore (line, UnIgnore))
      goto done;

    if (last)
    {
      last->next = mutt_new_list ();
      last = last->next;
    }
    else
      last = e->userhdrs = mutt_new_list ();
    last->data = safe_strdup (line);
    if (do_2047)
      rfc2047_decode (&last->data);
  }

  done:
  
  *lastp = last;
  return matched;
}
  
  
/* mutt_read_rfc822_header() -- parses a RFC822 header
 *
 * Args:
 *
 * f		stream to read from
 *
 * hdr		header structure of current message (optional).
 * 
 * user_hdrs	If set, store user headers.  Used for recall-message and
 * 		postpone modes.
 * 
 * weed		If this parameter is set and the user has activated the
 * 		$weed option, honor the header weed list for user headers.
 * 	        Used for recall-message.
 * 
 * Returns:     newly allocated envelope structure.  You should free it by
 *              mutt_free_envelope() when envelope stay unneeded.
 */
ENVELOPE *mutt_read_rfc822_header (FILE *f, HEADER *hdr, short user_hdrs,
				   short weed)
{
  ENVELOPE *e = mutt_new_envelope();
  LIST *last = NULL;
  char *line = safe_malloc (LONG_STRING);
  char *p;
  LOFF_T loc;
  size_t linelen = LONG_STRING;
  char buf[LONG_STRING+1];

  if (hdr)
  {
    if (hdr->content == NULL)
    {
      hdr->content = mutt_new_body ();

      /* set the defaults from RFC1521 */
      hdr->content->type        = TYPETEXT;
      hdr->content->subtype     = safe_strdup ("plain");
      hdr->content->encoding    = ENC7BIT;
      hdr->content->length      = -1;

      /* RFC 2183 says this is arbitrary */
      hdr->content->disposition = DISPINLINE;
    }
  }

  while ((loc = ftello (f)),
	  *(line = mutt_read_rfc822_line (f, line, &linelen)) != 0)
  {
    if ((p = strpbrk (line, ": \t")) == NULL || *p != ':')
    {
      char return_path[LONG_STRING];
      time_t t;

      /* some bogus MTAs will quote the original "From " line */
      if (mutt_strncmp (">From ", line, 6) == 0)
	continue; /* just ignore */
      else if (is_from (line, return_path, sizeof (return_path), &t))
      {
	/* MH sometimes has the From_ line in the middle of the header! */
	if (hdr && !hdr->received)
	  hdr->received = t - mutt_local_tz (t);
	continue;
      }

      fseeko (f, loc, 0);
      break; /* end of header */
    }

    *buf = '\0';

    if (mutt_match_spam_list(line, SpamList, buf, sizeof(buf)))
    {
      if (!mutt_match_rx_list(line, NoSpamList))
      {

	/* if spam tag already exists, figure out how to amend it */
	if (e->spam && *buf)
	{
	  /* If SpamSep defined, append with separator */
	  if (SpamSep)
	  {
	    mutt_buffer_addstr(e->spam, SpamSep);
	    mutt_buffer_addstr(e->spam, buf);
	  }

	  /* else overwrite */
	  else
	  {
	    e->spam->dptr = e->spam->data;
	    *e->spam->dptr = '\0';
	    mutt_buffer_addstr(e->spam, buf);
	  }
	}

	/* spam tag is new, and match expr is non-empty; copy */
	else if (!e->spam && *buf)
	{
	  e->spam = mutt_buffer_from (buf);
	}

	/* match expr is empty; plug in null string if no existing tag */
	else if (!e->spam)
	{
	  e->spam = mutt_buffer_from("");
	}

	if (e->spam && e->spam->data)
          dprint(5, (debugfile, "p822: spam = %s\n", e->spam->data));
      }
    }

    *p = 0;
    p = skip_email_wsp(p + 1);
    if (!*p)
      continue; /* skip empty header fields */

    mutt_parse_rfc822_line (e, hdr, line, p, user_hdrs, weed, 1, &last);
  }

  FREE (&line);

  if (hdr)
  {
    hdr->content->hdr_offset = hdr->offset;
    hdr->content->offset = ftello (f);

    /* do RFC2047 decoding */
    rfc2047_decode_adrlist (e->from);
    rfc2047_decode_adrlist (e->to);
    rfc2047_decode_adrlist (e->cc);
    rfc2047_decode_adrlist (e->bcc);
    rfc2047_decode_adrlist (e->reply_to);
    rfc2047_decode_adrlist (e->mail_followup_to);
    rfc2047_decode_adrlist (e->return_path);
    rfc2047_decode_adrlist (e->sender);
    rfc2047_decode (&e->x_label);

    if (e->subject)
    {
      regmatch_t pmatch[1];

      rfc2047_decode (&e->subject);

      if (regexec (ReplyRegexp.rx, e->subject, 1, pmatch, 0) == 0)
	e->real_subj = e->subject + pmatch[0].rm_eo;
      else
	e->real_subj = e->subject;
    }

    if (hdr->received < 0)
    {
      dprint(1,(debugfile,"read_rfc822_header(): resetting invalid received time to 0\n"));
      hdr->received = 0;
    }

    /* check for missing or invalid date */
    if (hdr->date_sent <= 0)
    {
      dprint(1,(debugfile,"read_rfc822_header(): no date found, using received time from msg separator\n"));
      hdr->date_sent = hdr->received;
    }
  }

  return (e);
}

ADDRESS *mutt_parse_adrlist (ADDRESS *p, const char *s)
{
  const char *q;

  /* check for a simple whitespace separated list of addresses */
  if ((q = strpbrk (s, "\"<>():;,\\")) == NULL)
  {
    char tmp[HUGE_STRING];
    char *r;

    strfcpy (tmp, s, sizeof (tmp));
    r = tmp;
    while ((r = strtok (r, " \t")) != NULL)
    {
      p = rfc822_parse_adrlist (p, r);
      r = NULL;
    }
  }
  else
    p = rfc822_parse_adrlist (p, s);
  
  return p;
}

/* Compares mime types to the ok and except lists */
static int count_body_parts_check(LIST **checklist, BODY *b, int dflt)
{
  LIST *type;
  ATTACH_MATCH *a;

  /* If list is null, use default behavior. */
  if (! *checklist)
  {
    /*return dflt;*/
    return 0;
  }

  for (type = *checklist; type; type = type->next)
  {
    a = (ATTACH_MATCH *)type->data;
    dprint(5, (debugfile, "cbpc: %s %d/%s ?? %s/%s [%d]... ",
		dflt ? "[OK]   " : "[EXCL] ",
		b->type, b->subtype, a->major, a->minor, a->major_int));
    if ((a->major_int == TYPEANY || a->major_int == b->type) &&
	!regexec(&a->minor_rx, b->subtype, 0, NULL, 0))
    {
      dprint(5, (debugfile, "yes\n"));
      return 1;
    }
    else
    {
      dprint(5, (debugfile, "no\n"));
    }
  }

  return 0;
}

#define AT_COUNT(why)   { shallcount = 1; }
#define AT_NOCOUNT(why) { shallcount = 0; }

static int count_body_parts (BODY *body, int flags)
{
  int count = 0;
  int shallcount, shallrecurse;
  BODY *bp;

  if (body == NULL)
    return 0;

  for (bp = body; bp != NULL; bp = bp->next)
  {
    /* Initial disposition is to count and not to recurse this part. */
    AT_COUNT("default");
    shallrecurse = 0;

    dprint(5, (debugfile, "bp: desc=\"%s\"; fn=\"%s\", type=\"%d/%s\"\n",
	   bp->description ? bp->description : ("none"),
	   bp->filename ? bp->filename :
			bp->d_filename ? bp->d_filename : "(none)",
	   bp->type, bp->subtype ? bp->subtype : "*"));

    if (bp->type == TYPEMESSAGE)
    {
      shallrecurse = 1;

      /* If it's an external body pointer, don't recurse it. */
      if (!ascii_strcasecmp (bp->subtype, "external-body"))
	shallrecurse = 0;

      /* Don't count containers if they're top-level. */
      if (flags & MUTT_PARTS_TOPLEVEL)
	AT_NOCOUNT("top-level message/*");
    }
    else if (bp->type == TYPEMULTIPART)
    {
      /* Always recurse multiparts, except multipart/alternative. */
      shallrecurse = 1;
      if (!ascii_strcasecmp(bp->subtype, "alternative"))
        shallrecurse = 0;

      /* Don't count containers if they're top-level. */
      if (flags & MUTT_PARTS_TOPLEVEL)
	AT_NOCOUNT("top-level multipart");
    }

    if (bp->disposition == DISPINLINE &&
        bp->type != TYPEMULTIPART && bp->type != TYPEMESSAGE && bp == body)
      AT_NOCOUNT("ignore fundamental inlines");

    /* If this body isn't scheduled for enumeration already, don't bother
     * profiling it further.
     */
    if (shallcount)
    {
      /* Turn off shallcount if message type is not in ok list,
       * or if it is in except list. Check is done separately for
       * inlines vs. attachments.
       */

      if (bp->disposition == DISPATTACH)
      {
        if (!count_body_parts_check(&AttachAllow, bp, 1))
	  AT_NOCOUNT("attach not allowed");
        if (count_body_parts_check(&AttachExclude, bp, 0))
	  AT_NOCOUNT("attach excluded");
      }
      else
      {
        if (!count_body_parts_check(&InlineAllow, bp, 1))
	  AT_NOCOUNT("inline not allowed");
        if (count_body_parts_check(&InlineExclude, bp, 0))
	  AT_NOCOUNT("excluded");
      }
    }

    if (shallcount)
      count++;
    bp->attach_qualifies = shallcount ? 1 : 0;

    dprint(5, (debugfile, "cbp: %p shallcount = %d\n", (void *)bp, shallcount));

    if (shallrecurse)
    {
      dprint(5, (debugfile, "cbp: %p pre count = %d\n", (void *)bp, count));
      bp->attach_count = count_body_parts(bp->parts, flags & ~MUTT_PARTS_TOPLEVEL);
      count += bp->attach_count;
      dprint(5, (debugfile, "cbp: %p post count = %d\n", (void *)bp, count));
    }
  }

  dprint(5, (debugfile, "bp: return %d\n", count < 0 ? 0 : count));
  return count < 0 ? 0 : count;
}

int mutt_count_body_parts (CONTEXT *ctx, HEADER *hdr)
{
  short keep_parts = 0;

  if (hdr->attach_valid)
    return hdr->attach_total;
  
  if (hdr->content->parts)
    keep_parts = 1;
  else
    mutt_parse_mime_message (ctx, hdr);
  
  if (AttachAllow || AttachExclude || InlineAllow || InlineExclude)
    hdr->attach_total = count_body_parts(hdr->content, MUTT_PARTS_TOPLEVEL);
  else
    hdr->attach_total = 0;

  hdr->attach_valid = 1;
  
  if (!keep_parts)
    mutt_free_body (&hdr->content->parts);
  
  return hdr->attach_total;
}