Add support for duplicate "charset" parameters with matching values (a11c9934) · Commits · e / os / Mail

mail/common/src/main/java/com/fsck/k9/mail/internet/MessageExtractor.java

+1 −2

Original line number	Diff line number	Diff line
		@@ -23,7 +23,6 @@ import org.apache.commons.io.input.BoundedInputStream;
		import timber.log.Timber;

		import static com.fsck.k9.mail.internet.CharsetSupport.fixupCharset;
		import static com.fsck.k9.mail.internet.MimeUtility.getHeaderParameter;
		import static com.fsck.k9.mail.internet.MimeUtility.isSameMimeType;
		import static com.fsck.k9.mail.internet.Viewable.Alternative;
		import static com.fsck.k9.mail.internet.Viewable.Html;
		@@ -77,7 +76,7 @@ public class MessageExtractor {
		/*
		* We've got a text part, so let's see if it needs to be processed further.
		*/
		String charset = getHeaderParameter(part.getContentType(), "charset");
		String charset = PartExtensions.getCharset(part);
		/*
		* determine the charset from HTML message.
		*/

mail/common/src/main/java/com/fsck/k9/mail/internet/MimeParameterDecoder.kt

+20 −0

Original line number	Diff line number	Diff line
		@@ -54,6 +54,26 @@ object MimeParameterDecoder {
		)
		}

		fun decodeBasic(headerBody: String): MimeValue {
		val parser = MimeHeaderParser(headerBody)

		val value = parser.readHeaderValue()
		parser.skipCFWS()
		if (parser.endReached()) {
		return MimeValue(value)
		}

		val (basicParameters, duplicateParameters, parserErrorIndex) = readBasicParameters(parser)
		val parameters = basicParameters.mapValues { (_, parameterValue) -> parameterValue.value }

		return MimeValue(
		value = value,
		parameters = parameters,
		ignoredParameters = duplicateParameters,
		parserErrorIndex = parserErrorIndex
		)
		}

		@JvmStatic
		fun extractHeaderValue(headerBody: String): String {
		val parser = MimeHeaderParser(headerBody)

mail/common/src/main/java/com/fsck/k9/mail/internet/PartExtensions.kt

0 → 100644

+24 −0

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		@file:JvmName("PartExtensions")
		package com.fsck.k9.mail.internet

		import com.fsck.k9.mail.Part

		/**
		* Return the `charset` parameter value of this [Part]'s `Content-Type` header.
		*/
		val Part.charset: String?
		get() {
		val contentTypeHeader = this.contentType ?: return null
		val (_, parameters, duplicateParameters) = MimeParameterDecoder.decodeBasic(contentTypeHeader)
		return parameters["charset"] ?: extractNonConflictingCharsetValue(duplicateParameters)
		}

		// If there are multiple "charset" parameters, but they all agree on the value, we use that value.
		private fun extractNonConflictingCharsetValue(duplicateParameters: List<Pair<String, String>>): String? {
		val charsets = duplicateParameters.asSequence()
		.filter { (parameterName, _) -> parameterName == "charset" }
		.map { (_, charset) -> charset.lowercase() }
		.toSet()

		return if (charsets.size == 1) charsets.first() else null
		}

mail/common/src/test/java/com/fsck/k9/mail/internet/PartExtensionsTest.kt

0 → 100644

+54 −0

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		package com.fsck.k9.mail.internet

		import com.google.common.truth.Truth.assertThat
		import org.junit.Test

		class PartExtensionsTest {
		@Test
		fun `get charset without charset parameter`() {
		assertGetCharset(headerValue = "text/plain", expectedCharset = null)
		}

		@Test
		fun `get charset with single charset parameter`() {
		assertGetCharset(headerValue = "text/plain; charset=UTF-8", expectedCharset = "utf-8")
		}

		@Test
		fun `get charset with single quoted charset parameter`() {
		assertGetCharset(headerValue = "text/plain; charset=\"iso-8859-1\"", expectedCharset = "ISO-8859-1")
		}

		@Test
		fun `get charset with two charset parameters where values match exactly`() {
		assertGetCharset(headerValue = "text/plain; charset=utf-8; charset=utf-8", expectedCharset = "utf-8")
		}

		@Test
		fun `get charset with two charset parameters where values differ in case`() {
		assertGetCharset(headerValue = "text/plain; charset=utf-8; charset=UTF-8", expectedCharset = "utf-8")
		}

		@Test
		fun `get charset with two charset parameters where values differ in quoting`() {
		assertGetCharset(headerValue = "text/plain; charset=utf-8; charset=\"utf-8\"", expectedCharset = "utf-8")
		}

		@Test
		fun `get charset with two charset parameters with conflicting values`() {
		assertGetCharset(headerValue = "text/plain; charset=utf-8; charset=iso-8859-1", expectedCharset = null)
		}

		@Test
		fun `get charset with extended parameter syntax`() {
		assertGetCharset(headerValue = "text/plain; charset*=us-ascii'en-us'utf-8", expectedCharset = null)
		}

		private fun assertGetCharset(headerValue: String, expectedCharset: String?) {
		val part = MimeBodyPart.create(null, headerValue)

		val charset = part.charset

		assertThat(charset).ignoringCase().isEqualTo(expectedCharset)
		}
		}