util/MimeType: add ParseMimeTypeParameters()

src/util/MimeType.cxx

@@ -18,6 +18,7 @@
  */
 
 #include "MimeType.hxx"
+#include "SplitString.hxx"
 
 #include <string.h>
 
@@ -29,3 +30,24 @@ GetMimeTypeBase(const char *s)
 		? std::string(s, semicolon)
 		: std::string(s);
 }
+
+std::map<std::string, std::string>
+ParseMimeTypeParameters(const char *s)
+{
+	std::map<std::string, std::string> result;
+
+	auto l = SplitString(s, ';', true);
+	if (!l.empty())
+		l.pop_front();
+
+	for (const auto &i : l) {
+		const auto eq = i.find('=');
+		if (eq == i.npos)
+			continue;
+
+		result.insert(std::make_pair(std::string(&i.front(), eq),
+					     std::string(&i[eq + 1])));
+	}
+
+	return result;
+}

src/util/MimeType.hxx

@@ -21,6 +21,7 @@
 #define MPD_MIME_TYPE_HXX
 
 #include <string>
+#include <map>
 
 /**
  * Extract the part of the MIME type before the parameters, i.e. the
@@ -30,4 +31,13 @@
 std::string
 GetMimeTypeBase(const char *s);
 
+/**
+ * Parse the parameters from a MIME type string.  Parameters are
+ * separated by semicolon.  Example:
+ *
+ * "foo/bar; param1=value1; param2=value2"
+ */
+std::map<std::string, std::string>
+ParseMimeTypeParameters(const char *s);
+
 #endif

test/MimeTypeTest.hxx

@@ -13,6 +13,7 @@
 class MimeTypeTest : public CppUnit::TestFixture {
 	CPPUNIT_TEST_SUITE(MimeTypeTest);
 	CPPUNIT_TEST(TestBase);
+	CPPUNIT_TEST(TestParameters);
 	CPPUNIT_TEST_SUITE_END();
 
 public:
@@ -25,4 +26,24 @@ public:
 		CPPUNIT_ASSERT("foo/bar" == GetMimeTypeBase("foo/bar; x=y"));
 		CPPUNIT_ASSERT("foo/bar" == GetMimeTypeBase("foo/bar;x=y"));
 	}
+
+	void TestParameters() {
+		CPPUNIT_ASSERT(ParseMimeTypeParameters("").empty());
+		CPPUNIT_ASSERT(ParseMimeTypeParameters("foo/bar").empty());
+		CPPUNIT_ASSERT(ParseMimeTypeParameters("foo/bar;").empty());
+		CPPUNIT_ASSERT(ParseMimeTypeParameters("foo/bar;garbage").empty());
+		CPPUNIT_ASSERT(ParseMimeTypeParameters("foo/bar; garbage").empty());
+
+		auto p = ParseMimeTypeParameters("foo/bar;a=b");
+		CPPUNIT_ASSERT(!p.empty());
+		CPPUNIT_ASSERT(p["a"] == "b");
+		CPPUNIT_ASSERT(p.size() == 1);
+
+		p = ParseMimeTypeParameters("foo/bar; a=b;c;d=e ; f=g ");
+		CPPUNIT_ASSERT(!p.empty());
+		CPPUNIT_ASSERT(p["a"] == "b");
+		CPPUNIT_ASSERT(p["d"] == "e");
+		CPPUNIT_ASSERT(p["f"] == "g");
+		CPPUNIT_ASSERT(p.size() == 3);
+	}
 };