capstone: Convert Makefile bits to meson bits

There are better ways to do this, e.g. meson cmake subproject,
but that requires cmake 3.7 and some of our CI environments
only provide cmake 3.5.

Nor can we add a meson.build file to capstone/, because the git
submodule would then always report "untracked files".  Fixing that
would require creating our own branch on the qemu git mirror, at
which point we could just as easily create a native meson subproject.

Instead, build the library via the main meson.build.

This improves the current state of affairs in that we will re-link
the qemu executables against a changed libcapstone.a, which we wouldn't
do before-hand.  In addition, the use of the configuration header file
instead of command-line -DEFINES means that we will rebuild the
capstone objects with changes to meson.build.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 103 insertions, 7 deletions

diff --git a/meson.build b/meson.build
index 3161c1f037..b9f6e84c2b 100644
--- a/meson.build
+++ b/meson.build
@@ -10,6 +10,7 @@ else
   keyval = import('unstable-keyval')
 endif
 ss = import('sourceset')
+fs = import('fs')
 
 sh = find_program('sh')
 cc = meson.get_compiler('c')
@@ -495,11 +496,6 @@ if 'CONFIG_USB_LIBUSB' in config_host
   libusb = declare_dependency(compile_args: config_host['LIBUSB_CFLAGS'].split(),
                               link_args: config_host['LIBUSB_LIBS'].split())
 endif
-capstone = not_found
-if 'CONFIG_CAPSTONE' in config_host
-  capstone = declare_dependency(compile_args: config_host['CAPSTONE_CFLAGS'].split(),
-                                link_args: config_host['CAPSTONE_LIBS'].split())
-endif
 libpmem = not_found
 if 'CONFIG_LIBPMEM' in config_host
   libpmem = declare_dependency(compile_args: config_host['LIBPMEM_CFLAGS'].split(),
@@ -581,7 +577,6 @@ foreach k, v: config_host
     config_host_data.set(k, v == 'y' ? 1 : v)
   endif
 endforeach
-genh += configure_file(output: 'config-host.h', configuration: config_host_data)
 
 minikconf = find_program('scripts/minikconf.py')
 config_all = {}
@@ -736,6 +731,107 @@ config_all += {
   'CONFIG_ALL': true,
 }
 
+# Submodules
+
+capstone = not_found
+capstone_opt = get_option('capstone')
+if capstone_opt in ['enabled', 'auto', 'system']
+  have_internal = fs.exists(meson.current_source_dir() / 'capstone/Makefile')
+  capstone = dependency('capstone', static: enable_static,
+                        method: 'pkg-config',
+                        required: capstone_opt == 'system' or
+                                  capstone_opt == 'enabled' and not have_internal)
+  if capstone.found()
+    capstone_opt = 'system'
+  elif have_internal
+    capstone_opt = 'internal'
+  else
+    capstone_opt = 'disabled'
+  endif
+endif
+if capstone_opt == 'internal'
+  capstone_data = configuration_data()
+  capstone_data.set('CAPSTONE_USE_SYS_DYN_MEM', '1')
+
+  capstone_files = files(
+    'capstone/cs.c',
+    'capstone/MCInst.c',
+    'capstone/MCInstrDesc.c',
+    'capstone/MCRegisterInfo.c',
+    'capstone/SStream.c',
+    'capstone/utils.c'
+  )
+
+  if 'CONFIG_ARM_DIS' in config_all_disas
+    capstone_data.set('CAPSTONE_HAS_ARM', '1')
+    capstone_files += files(
+      'capstone/arch/ARM/ARMDisassembler.c',
+      'capstone/arch/ARM/ARMInstPrinter.c',
+      'capstone/arch/ARM/ARMMapping.c',
+      'capstone/arch/ARM/ARMModule.c'
+    )
+  endif
+
+  # FIXME: This config entry currently depends on a c++ compiler.
+  # Which is needed for building libvixl, but not for capstone.
+  if 'CONFIG_ARM_A64_DIS' in config_all_disas
+    capstone_data.set('CAPSTONE_HAS_ARM64', '1')
+    capstone_files += files(
+      'capstone/arch/AArch64/AArch64BaseInfo.c',
+      'capstone/arch/AArch64/AArch64Disassembler.c',
+      'capstone/arch/AArch64/AArch64InstPrinter.c',
+      'capstone/arch/AArch64/AArch64Mapping.c',
+      'capstone/arch/AArch64/AArch64Module.c'
+    )
+  endif
+
+  if 'CONFIG_PPC_DIS' in config_all_disas
+    capstone_data.set('CAPSTONE_HAS_POWERPC', '1')
+    capstone_files += files(
+      'capstone/arch/PowerPC/PPCDisassembler.c',
+      'capstone/arch/PowerPC/PPCInstPrinter.c',
+      'capstone/arch/PowerPC/PPCMapping.c',
+      'capstone/arch/PowerPC/PPCModule.c'
+    )
+  endif
+
+  if 'CONFIG_I386_DIS' in config_all_disas
+    capstone_data.set('CAPSTONE_HAS_X86', 1)
+    capstone_files += files(
+      'capstone/arch/X86/X86Disassembler.c',
+      'capstone/arch/X86/X86DisassemblerDecoder.c',
+      'capstone/arch/X86/X86ATTInstPrinter.c',
+      'capstone/arch/X86/X86IntelInstPrinter.c',
+      'capstone/arch/X86/X86Mapping.c',
+      'capstone/arch/X86/X86Module.c'
+    )
+  endif
+
+  configure_file(output: 'capstone-defs.h', configuration: capstone_data)
+
+  capstone_cargs = [
+    # FIXME: There does not seem to be a way to completely replace the c_args
+    # that come from add_project_arguments() -- we can only add to them.
+    # So: disable all warnings with a big hammer.
+    '-Wno-error', '-w',
+
+    # Include all configuration defines via a header file, which will wind up
+    # as a dependency on the object file, and thus changes here will result
+    # in a rebuild.
+    '-include', 'capstone-defs.h'
+  ]
+
+  libcapstone = static_library('capstone',
+                               sources: capstone_files,
+                               c_args: capstone_cargs,
+                               include_directories: 'capstone/include')
+  capstone = declare_dependency(link_with: libcapstone,
+                                include_directories: 'capstone/include')
+endif
+config_host_data.set('CONFIG_CAPSTONE', capstone.found())
+
+genh += configure_file(output: 'config-host.h', configuration: config_host_data)
+
 # Generators
 
 hxtool = find_program('scripts/hxtool')
@@ -1566,7 +1662,7 @@ summary_info += {'vvfat support':     config_host.has_key('CONFIG_VVFAT')}
 summary_info += {'qed support':       config_host.has_key('CONFIG_QED')}
 summary_info += {'parallels support': config_host.has_key('CONFIG_PARALLELS')}
 summary_info += {'sheepdog support':  config_host.has_key('CONFIG_SHEEPDOG')}
-summary_info += {'capstone':          config_host.has_key('CONFIG_CAPSTONE')}
+summary_info += {'capstone':          capstone_opt == 'disabled' ? false : capstone_opt}
 summary_info += {'libpmem support':   config_host.has_key('CONFIG_LIBPMEM')}
 summary_info += {'libdaxctl support': config_host.has_key('CONFIG_LIBDAXCTL')}
 summary_info += {'libudev':           libudev.found()}