Initial support for serialization

[jchv]

Implements write support for some of the primitives, at least enough to write basic seqs. The API had to be shifted over a bit, but it should be API compatible, though this certainly breaks ABI compatibility. Does this matter? Is there any kind of major version bump to do? I do not think there is a practical way to avoid the ABI compatibility issue.

Currently the code here seems to build just fine, but I'm putting this PR in draft mode since I desire to do more testing and make sure it compiles with existing generated code.

Fixes #29.

[jchv]

Because unit tests hardcode the paths to the cpp files in the runtime, it is necessary to patch the test CMakeLists files.

diff --git a/spec/cpp_stl_11/CMakeLists.txt b/spec/cpp_stl_11/CMakeLists.txt
index 1176dab..8b411e6 100644
--- a/spec/cpp_stl_11/CMakeLists.txt
+++ b/spec/cpp_stl_11/CMakeLists.txt
@@ -26,7 +26,9 @@ set(PREREQ_SOURCES
 )
 
 set(RUNTIME_SOURCES
-       ${RUNTIME_SRC_PATH}/kaitai/kaitaistream.cpp
+       ${RUNTIME_SRC_PATH}/kaitai/kio.cpp
+       ${RUNTIME_SRC_PATH}/kaitai/kistream.cpp
+       ${RUNTIME_SRC_PATH}/kaitai/kostream.cpp
 )
 
 add_executable (ks_tests
diff --git a/spec/cpp_stl_98/CMakeLists.txt b/spec/cpp_stl_98/CMakeLists.txt
index f0ae8e8..069f867 100644
--- a/spec/cpp_stl_98/CMakeLists.txt
+++ b/spec/cpp_stl_98/CMakeLists.txt
@@ -22,7 +22,9 @@ set(PREREQ_SOURCES
 )
 
 set(RUNTIME_SOURCES
-       ${RUNTIME_SRC_PATH}/kaitai/kaitaistream.cpp
+       ${RUNTIME_SRC_PATH}/kaitai/kio.cpp
+       ${RUNTIME_SRC_PATH}/kaitai/kistream.cpp
+       ${RUNTIME_SRC_PATH}/kaitai/kostream.cpp
 )
 
 add_executable (ks_tests

For me locally, there are some tests that do not compile and one test that fails at master. However, that happens exactly the same regardless of whether I am using this version of the runtime or not, and are evidently fairly unrelated errors, so this PR is probably not broken.

Alternative solutions:

• kaitaistream.cpp file that includes the other cpp files.
• Linking to the other CMake project in a more regular fashion (may be ugly)
• Making C++ runtime header-only (I actually wonder why it isn't? This would definitely fix the ABI breakage problem.)

[JPenuchot]

Hello,

Any hope to see these merged in Kaitai someday ? This would pave the way for fixing an old issue in Mixxx (here).

Regards,
Jules

[jchv]

@JPenuchot: For what it's worth, this would only implement runtime primitives necessary for adding basic serialization support into Kaitai Struct for C++. Merging this would be a start, but we would also need to add support into the Kaitai Struct code generation portion as well.

[eoan-ermine]

@jchv @GreyCat

So, what's with this pull request? I saw that the code was reviewed, but it was not merged after that. Is there some kind of blocker?