ci ios

[mrobertseidowsky-gpsw]

Description:

This PR allows to:

• Compile ffmpeg sources for different ios host,
• Compile sxplayer sources for different ios host,
• Build libnodegl lib for each target,

One cross compilation file (.ini) per architecture (i.e processor type on the phone) is given as meson input.

Architectures are:

• x86_64: x86 processor 64-bit (ios simulator),
• arm64: arm processor 64-bit (iphone device).

Note that libnodegl tests :

• are compiled but not runned for arm64: they are automatically skipped (error code 77).
• are not compiled and runned for x86_64 because meson try to play it on ios simulator and it fails (signal 6 SIGABRT).

A badge inside README has been also added.

Notes:

• Declare in the cross file the cpp binary compiler (cpp = 'clang++') for arm64 target is mandatory, either it's not found automatically:

  • x86_64:

  C++ compiler for the build machine: c++ (clang 13.0.0 "Apple clang version 13.0.0 (clang-1300.0.29.30)")
  C++ linker for the build machine: c++ ld64 711
  C++ compiler for the host machine: c++ (clang 13.0.0 "Apple clang version 13.0.0 (clang-1300.0.29.30)")
  C++ linker for the host machine: c++ ld64 711
  

  • arm64:

  C++ compiler for the build machine: c++ (clang 13.0.0 "Apple clang version 13.0.0 (clang-1300.0.29.30)")
  C++ linker for the build machine: c++ ld64 711
  meson.build:429:6: ERROR: 'cpp' compiler binary not defined in cross or native file
  

• Declare in the cross file the compiler name for Objective C (objc_args) is mandatory for arm64 and x86_64, either some headers are not found while compiling Objective-C object (<UIKit/UIKit.h> from the UIKit framework which provides the core objects needed to build apps for iOS).

• Declare in the cross file the linker name of Objective C ( objc_link_args) and especially all the required ios frameworks is mandatory for arm64 and x86_64, either we get this kind of errors:

  Undefined symbols for architecture arm64/x86_64:
  "_CVOpenGLESTextureCacheCreate", referenced from:
  

  => CoreVideo framework needed.

  Undefined symbols for architecture arm64/x86_64:
  "_CFBundleGetBundleWithIdentifier", referenced from:
  

  => Foundation framework needed.

  Undefined symbols for architecture arm64/x86_64:
  "_OBJC_CLASS_$_EAGLContext", referenced from:
  

  => OpenGLES framework needed.