• Tor Lillqvist's avatar
    Re-think cppu::throwException() and the C++/UNO bridge on iOS · 7d6be61a
    Tor Lillqvist yazdı
    It seems that on iOS, where we don't have any Java, Python, BASIC, or
    other scripting, the only thing that would use the C++/UNO bridge
    functionality that invokes codeSnippet() was cppu::throwException().
    
    codeSnippet() is part of what corresponds to the code that uses
    run-time-generated machine code on other platforms. We can't generate
    code at run-time on iOS, that has been known forever. Instead we have
    used some manually written assembler to handle it instead. We used to
    have a Perl script to generate a set of code snippets for different
    cases, different numbers of parameters of the called function and
    whatnot, but that went away at some stage some year ago. (It is
    unclear whether that broke the C++/UNO bridge on iOS, or whether the
    stuff continued to work even after that.)
    
    Anyway, this handwritten assembly, or the manual construction of
    internal data structures for exceptions, or something else, seemed to
    have bit-rotten. Exceptions thrown with cppu::throwException() were
    not catchable properly any longer.
    
    Instead of digging in and trying to understand what is wrong, I chose
    another solution. It turns out that the number of types of exception
    objects thrown by cppu::throwException() is fairly small. During
    startup of the LibreOffice code, and loading of an .odt document, only
    one kind of exception is thrown this way... (The lovely
    css::ucb:InteractiveAugmentedIOException.)
    
    So we can simply have code that checks what the type of object being
    thrown is, and explicitgly throws such an object then with a normal
    C++ throw statement. Seems to work.
    
    Sadly the cppu::getCaughtException() API still needs some inline
    assembly in the C++/UNO brige. That seems to work though, knock on
    wood.
    
    This commit also adds a small "unit test" for iOS, copied from
    cppuhelperm to ImplSVMain(). Ideally we should not copy code around of
    course, but have a separate unit test app for iOS that would somehow
    include relevant unit tests from source files all over the place.
    Later.
    
    Change-Id: Ib6d9d5b6fb8cc684ec15c97a312ca2f720e87069
    Reviewed-on: https://gerrit.libreoffice.org/60506
    Tested-by: Jenkins
    Reviewed-by: 's avatarTor Lillqvist <tml@collabora.com>
    7d6be61a
Module_ios.mk 622 Bytes