mirror/taglib
1
0
Fork 0
mirror of https://github.com/taglib/taglib.git synced 2025-05-27 21:20:26 -04:00
Code Issues Packages Projects Releases Wiki Activity

Proper handling of MP4 atoms with zero length.

Browse Source 
If the size of an atom is 0, it designates the last atom which extends to the end of the file.
This commit is contained in:
Tsuda Kageyu 2016-11-02 15:44:50 +09:00
parent eb6d058ab9
commit f5ca097379
3 changed files with 18 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
taglib/mp4/mp4atom.cpp
View File

@ -54,10 +54,15 @@ MP4::Atom::Atom(File *file)
length = header.toUInt();
if(length == 1) {
if(length == 0) {
// The last atom which extends to the end of the file.
length = file->length() - offset;
}
else if(length == 1) {
// The atom has a 64-bit length.
const long long longLength = file->readBlock(8).toLongLong();
if(longLength <= LONG_MAX) {
// The atom has a 64-bit length, but it's actually a 31-bit value or long is 64-bit.
// The actual length fits in long. That's always the case if long is 64-bit.
length = static_cast<long>(longLength);
}
else {
@ -67,6 +72,7 @@ MP4::Atom::Atom(File *file)
return;
}
}
if(length < 8) {
debug("MP4: Invalid atom size");
length = 0;

BIN
tests/data/zero-length-mdat.m4a Normal file
View File

Binary file not shown.

10
tests/test_mp4.cpp
View File

@ -57,6 +57,7 @@ class TestMP4 : public CppUnit::TestFixture
CPPUNIT_TEST(testProperties);
CPPUNIT_TEST(testFuzzedFile);
CPPUNIT_TEST(testRepeatedSave);
CPPUNIT_TEST(testWithZeroLengthAtom);
CPPUNIT_TEST_SUITE_END();
public:
@ -395,6 +396,15 @@ public:
CPPUNIT_ASSERT_EQUAL(2862L, f.find("0123456789"));
CPPUNIT_ASSERT_EQUAL(-1L, f.find("0123456789", 2863));
}
void testWithZeroLengthAtom()
{
MP4::File f(TEST_FILE_PATH_C("zero-length-mdat.m4a"));
CPPUNIT_ASSERT(f.isValid());
CPPUNIT_ASSERT_EQUAL(1115, f.audioProperties()->lengthInMilliseconds());
CPPUNIT_ASSERT_EQUAL(22050, f.audioProperties()->sampleRate());
}
};
CPPUNIT_TEST_SUITE_REGISTRATION(TestMP4);