use quoted-printable or base64 to protect trailing spaces on PGP/MIME signing except for ISO-2022-JP.

git-svn-id: svn://sylpheed.sraoss.jp/sylpheed/trunk@1693 ee746299-78ed-0310-b773-934348b2243d

2 files changed, 38 insertions, 2 deletions

diff --git a/libsylph/procmime.c b/libsylph/procmime.c
index de5c92ba..24fa4441 100644
--- a/libsylph/procmime.c
+++ b/libsylph/procmime.c
@@ -1,6 +1,6 @@
 /*
  * LibSylph -- E-Mail client library
- * Copyright (C) 1999-2006 Hiroyuki Yamamoto
+ * Copyright (C) 1999-2007 Hiroyuki Yamamoto
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -1671,6 +1671,41 @@ EncodingType procmime_get_encoding_for_text_file(const gchar *file)
 	}
 }
 
+EncodingType procmime_get_encoding_for_str(const gchar *str)
+{
+	const guchar *p;
+	size_t octet_chars = 0;
+	size_t total_len = 0;
+	gfloat octet_percentage;
+
+	total_len = strlen(str);
+
+	for (p = str; *p != '\0'; ++p) {
+		if (*p & 0x80)
+			++octet_chars;
+	}
+
+	if (total_len > 0)
+		octet_percentage = (gfloat)octet_chars / (gfloat)total_len;
+	else
+		octet_percentage = 0.0;
+
+	debug_print("procmime_get_encoding_for_str(): "
+		    "8bit chars: %d / %d (%f%%)\n", octet_chars, total_len,
+		    100.0 * octet_percentage);
+
+	if (octet_percentage > 0.20) {
+		debug_print("using BASE64\n");
+		return ENC_BASE64;
+	} else if (octet_chars > 0) {
+		debug_print("using quoted-printable\n");
+		return ENC_QUOTED_PRINTABLE;
+	} else {
+		debug_print("using 7bit\n");
+		return ENC_7BIT;
+	}
+}
+
 const gchar *procmime_get_encoding_str(EncodingType encoding)
 {
 	static const gchar *encoding_str[] = {
diff --git a/libsylph/procmime.h b/libsylph/procmime.h
index 735cef68..8d5b1855 100644
--- a/libsylph/procmime.h
+++ b/libsylph/procmime.h
@@ -1,6 +1,6 @@
 /*
  * LibSylph -- E-Mail client library
- * Copyright (C) 1999-2006 Hiroyuki Yamamoto
+ * Copyright (C) 1999-2007 Hiroyuki Yamamoto
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -197,6 +197,7 @@ gint procmime_execute_open_file		(const gchar	*file,
 
 EncodingType procmime_get_encoding_for_charset	(const gchar	*charset);
 EncodingType procmime_get_encoding_for_text_file(const gchar	*file);
+EncodingType procmime_get_encoding_for_str	(const gchar	*str);
 const gchar *procmime_get_encoding_str		(EncodingType	 encoding);
 
 #endif /* __PROCMIME_H__ */