From: Stephan Bosch <stephan@dovecot.fi>
Date: Sat, 6 Aug 2016 15:59:10 +0000 (+0200)
Subject: istream-base64-encoder: Implemented proper stat function that returns the encoded... 
X-Git-Tag: 2.3.0.rc1~3233
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0b9667003a1d54aec1ef60dd8adedb80c5775b3a;p=thirdparty%2Fdovecot%2Fcore.git

istream-base64-encoder: Implemented proper stat function that returns the encoded size of the stream.

For Base64 encoding, the size of the encoded data can be determined from the input data size exactly.
---

diff --git a/src/lib/istream-base64-encoder.c b/src/lib/istream-base64-encoder.c
index 2b7b5670a2..b63c12e32b 100644
--- a/src/lib/istream-base64-encoder.c
+++ b/src/lib/istream-base64-encoder.c
@@ -143,6 +143,35 @@ i_stream_base64_encoder_seek(struct istream_private *stream,
 	i_stream_default_seek_nonseekable(stream, v_offset, mark);
 }
 
+static int
+i_stream_base64_encoder_stat(struct istream_private *stream,
+	bool exact ATTR_UNUSED)
+{
+	struct base64_encoder_istream *bstream =
+		(struct base64_encoder_istream *)stream;
+	const struct stat *st;
+	off_t newlines, size;
+
+	if (i_stream_stat(stream->parent, exact, &st) < 0) {
+		stream->istream.stream_errno = stream->parent->stream_errno;
+		return -1;
+	}
+
+	stream->statbuf = *st;
+	
+	/* calculate size of encoded data */
+	size = (st->st_size / 3) * 4 +
+		((st->st_size % 3) == 0 ? 0 : 4);
+
+	/* update size with added newlines */
+	newlines = (size / bstream->chars_per_line - 1) +
+		((size % bstream->chars_per_line) == 0 ? 0 : 1);
+	size += newlines * (bstream->crlf ? 2 : 1);
+
+	stream->statbuf.st_size = size;
+	return 0;
+}
+
 struct istream *
 i_stream_create_base64_encoder(struct istream *input,
 			       unsigned int chars_per_line, bool crlf)
@@ -158,6 +187,7 @@ i_stream_create_base64_encoder(struct istream *input,
 
 	bstream->istream.read = i_stream_base64_encoder_read;
 	bstream->istream.seek = i_stream_base64_encoder_seek;
+	bstream->istream.stat = i_stream_base64_encoder_stat;
 
 	bstream->istream.istream.readable_fd = FALSE;
 	bstream->istream.istream.blocking = input->blocking;
diff --git a/src/lib/test-istream-base64-encoder.c b/src/lib/test-istream-base64-encoder.c
index dcc564e786..e158078d1b 100644
--- a/src/lib/test-istream-base64-encoder.c
+++ b/src/lib/test-istream-base64-encoder.c
@@ -13,9 +13,22 @@ static struct test {
 } tests[] = {
 	{ "hello world", 80, FALSE, "aGVsbG8gd29ybGQ=" },
 	{ "hello world", 4, FALSE, "aGVs\nbG8g\nd29y\nbGQ=" },
-	{ "hello world", 4, TRUE, "aGVs\r\nbG8g\r\nd29y\r\nbGQ=", },
+	{ "hello world", 4, TRUE, "aGVs\r\nbG8g\r\nd29y\r\nbGQ=" },
+	{ "hello worlds", 80, FALSE, "aGVsbG8gd29ybGRz" },
+	{ "hello worlds", 4, FALSE, "aGVs\nbG8g\nd29y\nbGRz" },
+	{ "hello worlds", 4, TRUE, "aGVs\r\nbG8g\r\nd29y\r\nbGRz" },
+	{ "hell world", 80, FALSE, "aGVsbCB3b3JsZA==" },
+	{ "hell world", 4, FALSE, "aGVs\nbCB3\nb3Js\nZA==" },
+	{ "hell world", 4, TRUE, "aGVs\r\nbCB3\r\nb3Js\r\nZA==" },
+	{ "hello to the world!!", 80, FALSE,
+		"aGVsbG8gdG8gdGhlIHdvcmxkISE=" },
+	{ "hello to the world!!", 8, FALSE,
+		"aGVsbG8g\ndG8gdGhl\nIHdvcmxk\nISE=" },
+	{ "hello to the world!!", 8, TRUE,
+		"aGVsbG8g\r\ndG8gdGhl\r\nIHdvcmxk\r\nISE=" },
 };
 
+
 static const char *hello = "hello world";
 
 static void encode_test(const char *text, unsigned int chars_per_line,
@@ -24,6 +37,7 @@ static void encode_test(const char *text, unsigned int chars_per_line,
 	unsigned int i, text_len = strlen(text);
 	struct istream *input, *input_data;
 	const unsigned char *data;
+	uoff_t stream_size;
 	size_t size;
 	ssize_t ret;
 
@@ -43,6 +57,10 @@ static void encode_test(const char *text, unsigned int chars_per_line,
 	data = i_stream_get_data(input, &size);
 	test_assert(size == strlen(output) && memcmp(data, output, size) == 0);
 
+	ret = i_stream_get_size(input, TRUE, &stream_size);
+	test_assert(ret > 0);
+	test_assert(size == stream_size);
+
 	i_stream_unref(&input);
 	i_stream_unref(&input_data);
 }