Implement RFC 2231.

1 files changed, 312 insertions, 0 deletions

diff --git a/rfc2231.c b/rfc2231.c
new file mode 100644
index 00000000..2ef80b14
--- /dev/null
+++ b/rfc2231.c
@@ -0,0 +1,312 @@
+/*
+ * Copyright (C) 1999 Thomas Roessler <roessler@guug.de>
+ *
+ *     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., 675 Mass Ave, Cambridge, MA
+ *     02139, USA.
+ */
+
+/*
+ * Yet another MIME encoding for header data.  This time, it's
+ * parameters, specified in RFC 2231, and modeled after the
+ * encoding used in URLs.
+ * 
+ * Additionally, continuations and encoding are mixed in an, errrm,
+ * interesting manner.
+ *
+ */
+
+#include "mutt.h"
+#include "mime.h"
+#include "charset.h"
+#include "rfc2047.h"
+#include "rfc2231.h"
+
+#include <ctype.h>
+#include <string.h>
+#include <stdlib.h>
+
+struct rfc2231_parameter
+{
+  char *attribute;
+  char *value;
+  int  index;
+  int  encoded;
+  struct rfc2231_parameter 
+       *next;
+};
+
+static char *rfc2231_get_charset (char *, char *, size_t);
+static struct rfc2231_parameter *rfc2231_new_parameter (void);
+static void rfc2231_decode_one (char *, char *, char *);
+static void rfc2231_free_parameter (struct rfc2231_parameter **);
+static void rfc2231_join_continuations (PARAMETER **, struct rfc2231_parameter *);
+static void rfc2231_list_insert (struct rfc2231_parameter **, struct rfc2231_parameter *);
+
+void rfc2231_decode_parameters (PARAMETER **headp)
+{
+  PARAMETER *head = NULL;
+  PARAMETER **last;
+  PARAMETER *p, *q;
+
+  struct rfc2231_parameter *conthead = NULL;
+  struct rfc2231_parameter *conttmp;
+
+  char *s, *t;
+  char charset[STRING];
+
+  int encoded;
+  int index;
+  
+  if (!headp) return;
+  
+  for (last = &head, p = *headp; p; p = q)
+  {
+    q = p->next;
+
+    if (!(s = strchr (p->attribute, '*')))
+    {
+
+      /* 
+       * Using RFC 2047 encoding in MIME parameters is explicitly
+       * forbidden by that document.  Nevertheless, it's being
+       * generated by some software, including certain Lotus Notes to 
+       * Internet Gateways.  So we actually decode it.
+       */
+
+      if (option (OPTRFC2047PARAMS) && strstr (p->value, "=?"))
+	rfc2047_decode (p->value, p->value, strlen (p->value) + 1);
+
+      *last = p;
+      last = &p->next;
+      p->next = NULL;
+    }
+    else if (*(s + 1) == '\0')
+    {
+      *s = '\0';
+      
+      s = rfc2231_get_charset (p->value, charset, sizeof (charset));
+      rfc2231_decode_one (p->value, s, charset);
+
+      *last = p;
+      last = &p->next;
+      p->next = NULL;
+    }
+    else
+    {
+      *s = '\0'; s++; /* let s point to the first character of index. */
+      for (t = s; *t && isdigit (*t); t++)
+	;
+      encoded = (*t == '*');
+      *t = '\0';
+
+      index = atoi (s);
+
+      conttmp = rfc2231_new_parameter ();
+      conttmp->attribute = p->attribute;
+      conttmp->value = p->value;
+      conttmp->encoded = encoded;
+      conttmp->index = index;
+      
+      p->attribute = NULL;
+      p->value = NULL;
+      safe_free ((void **) &p);
+
+      rfc2231_list_insert (&conthead, conttmp);
+
+    }
+  }
+
+  if (conthead)
+    rfc2231_join_continuations (last, conthead);
+  
+  *headp = head;
+}
+  
+static struct rfc2231_parameter *rfc2231_new_parameter (void)
+{
+  return safe_calloc (sizeof (struct rfc2231_parameter), 1);
+}
+
+static void rfc2231_free_parameter (struct rfc2231_parameter **p)
+{
+  if (*p)
+  {
+    safe_free ((void **) &(*p)->attribute);
+    safe_free ((void **) &(*p)->value);
+    safe_free ((void **) p);
+  }
+}
+
+static char *rfc2231_get_charset (char *value, char *charset, size_t chslen)
+{
+  char *t, *u;
+  
+  if (!(t = strchr (value, '\'')))
+  {
+    charset[0] = '\0';
+    return value;
+  }
+  
+  *t = '\0';
+  strfcpy (charset, value, chslen);
+  
+  if ((u = strchr (t + 1, '\'')))
+    return u + 1;
+  else
+    return t + 1;
+}
+
+static void rfc2231_decode_one (char *dest, char *src, char *chs)
+{
+  char *d;
+
+  for (d = dest; *src; src++)
+  {
+    if (*src == '%' && isxdigit (*(src + 1)) && isxdigit (*(src + 2)))
+    {
+      *d++ = (hexval (*(src + 1)) << 4) | (hexval (*(src + 2)));
+      src += 2;
+    }
+    else
+      *d++ = *src;
+  }
+  
+  *d = '\0';
+  
+  if (chs && strcmp (chs, "us-ascii") && strcmp (chs, Charset))
+    mutt_display_string (dest, mutt_get_translation (chs, Charset));
+}
+
+/* insert parameter into an ordered list.
+ * 
+ * Primary sorting key: attribute
+ * Secondary sorting key: index
+ */
+
+static void rfc2231_list_insert (struct rfc2231_parameter **list,
+				 struct rfc2231_parameter *par)
+{
+  struct rfc2231_parameter **last = list;
+  struct rfc2231_parameter *p = *list, *q;
+  int c;
+  
+  while (p)
+  {
+    last = &p->next;
+    q = p; p = p->next;
+
+    c = strcmp (par->value, q->value);
+    if ((c > 0) || (c == 0 && par->index >= q->index))
+      break;
+  }
+  
+  par->next = p;
+  *last = par;
+}
+
+/* process continuation parameters */
+
+static void rfc2231_join_continuations (PARAMETER **head,
+					struct rfc2231_parameter *par)
+{
+  struct rfc2231_parameter *q;
+
+  char attribute[STRING];
+  char charset[STRING];
+  char *value = NULL;
+  char *valp;
+  int encoded;
+
+  size_t l, vl;
+  
+  while (par)
+  {
+    value = NULL; l = 0;
+    
+    strfcpy (attribute, par->attribute, sizeof (attribute));
+
+    if ((encoded = par->encoded))
+      valp = rfc2231_get_charset (par->value, charset, sizeof (charset));
+    else
+      valp = par->value;
+
+    do 
+    {
+      if (encoded && par->encoded)
+	rfc2231_decode_one (par->value, valp, charset);
+      
+      vl = strlen (par->value);
+      
+      safe_realloc ((void **) &value, l + vl + 1);
+      strcpy (value + l, par->value);
+      l += vl;
+
+      q = par->next;
+      rfc2231_free_parameter (&par);
+      if ((par = q))
+	valp = par->value;
+    } while (par && !strcmp (par->attribute, attribute));
+    
+    if (value)
+    {
+      *head = mutt_new_parameter ();
+      (*head)->attribute = safe_strdup (attribute);
+      (*head)->value = value;
+      head = &(*head)->next;
+    }
+  }
+}
+
+int rfc2231_encode (char *dest, size_t l, unsigned char *src)
+{
+  char buff[LONG_STRING];
+  unsigned char *s;
+  char *t;
+  int encode = 0;
+
+  for (s = src; *s && !encode; s++)
+  {
+    if (*s & 0x80)
+      encode = 1;
+  }
+
+  if (!encode)
+    strfcpy (dest, (char *) src, l);
+  else
+  {
+    for (s = src, t = buff; *s && (t - buff) < sizeof (buff) - 4; s++)
+    {
+      if ((*s & 0x80) || *s == '\'')
+      {
+	sprintf ((char *) t, "%%%02x", (unsigned int) *s);
+	t += 3;
+      }
+      else
+	*t++ = *s;
+    }
+    *t = '\0';
+    
+    if (Charset && SendCharset && mutt_strcasecmp (Charset, SendCharset))
+      mutt_display_string (buff, mutt_get_translation (Charset, SendCharset));
+
+    snprintf (dest, l, "%s''%s", SendCharset ? SendCharset :
+	      (Charset ? Charset : "unknown-8bit"), buff);
+  }
+
+  return encode;
+}
+