Add gn_to_bp script for SkQP.

This refactors the current gn_to_bp script and moves the common
components into a utils class.  Both gn_to_bp scripts now also
accept an optional param (--gn <gn_path>) to make it easier to run
within the Android tree where we don't have the DEPS synced.

Change-Id: Idc4de7b3993e63e21a5b7137b1873d82a8e1843e
Reviewed-on: https://skia-review.googlesource.com/102184
Commit-Queue: Derek Sollenberger <djsollen@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>

3 files changed, 342 insertions, 87 deletions

diff --git a/gn/gn_to_bp.py b/gn/gn_to_bp.py
index 5b6b3c7021..3d5dcb6c94 100644
--- a/gn/gn_to_bp.py
+++ b/gn/gn_to_bp.py
@@ -14,6 +14,8 @@ import string
 import subprocess
 import tempfile
 
+import gn_to_bp_utils
+
 # First we start off with a template for Android.bp,
 # with holes for source lists and include directories.
 bp = string.Template('''// This file is autogenerated by gn_to_bp.py.
@@ -213,12 +215,8 @@ gn_args = {
   'target_os':          '"android"',
   'skia_vulkan_header': '"Skia_Vulkan_Android.h"',
 }
-gn_args = ' '.join(sorted('%s=%s' % (k,v) for (k,v) in gn_args.iteritems()))
-
-tmp = tempfile.mkdtemp()
-subprocess.check_call(['gn', 'gen', tmp, '--args=%s' % gn_args, '--ide=json'])
 
-js = json.load(open(os.path.join(tmp, 'project.json')))
+js = gn_to_bp_utils.GenerateJSONFromGN(gn_args)
 
 def strip_slashes(lst):
   return {str(p.lstrip('/')) for p in lst}
@@ -228,6 +226,7 @@ cflags          = strip_slashes(js['targets']['//:skia']['cflags'])
 cflags_cc       = strip_slashes(js['targets']['//:skia']['cflags_cc'])
 local_includes  = strip_slashes(js['targets']['//:skia']['include_dirs'])
 export_includes = strip_slashes(js['targets']['//:public']['include_dirs'])
+defines      = [str(d) for d in js['targets']['//:skia']['defines']]
 
 dm_srcs         = strip_slashes(js['targets']['//:dm']['sources'])
 dm_includes     = strip_slashes(js['targets']['//:dm']['include_dirs'])
@@ -236,81 +235,28 @@ nanobench_target = js['targets']['//:nanobench']
 nanobench_srcs     = strip_slashes(nanobench_target['sources'])
 nanobench_includes = strip_slashes(nanobench_target['include_dirs'])
 
-def GrabDependentSrcs(name, srcs_to_extend, exclude):
-  # Grab the sources from other targets that $name depends on (e.g. optional
-  # Skia components, gms, tests, etc).
-  for dep in js['targets'][name]['deps']:
-    if 'third_party' in dep:
-      continue   # We've handled all third-party DEPS as static or shared_libs.
-    if 'none' in dep:
-      continue   # We'll handle all cpu-specific sources manually later.
-    if exclude and exclude in dep:
-      continue
-    srcs_to_extend.update(strip_slashes(js['targets'][dep].get('sources', [])))
-    GrabDependentSrcs(dep, srcs_to_extend, exclude)
-
-GrabDependentSrcs('//:skia', srcs, None)
-GrabDependentSrcs('//:dm', dm_srcs, 'skia')
-GrabDependentSrcs('//:nanobench', nanobench_srcs, 'skia')
+gn_to_bp_utils.GrabDependentValues(js, '//:skia', 'sources', srcs, None)
+gn_to_bp_utils.GrabDependentValues(js, '//:dm', 'sources', dm_srcs, 'skia')
+gn_to_bp_utils.GrabDependentValues(js, '//:nanobench', 'sources',
+                                   nanobench_srcs, 'skia')
 
 # No need to list headers.
 srcs            = {s for s in srcs           if not s.endswith('.h')}
 dm_srcs         = {s for s in dm_srcs        if not s.endswith('.h')}
 nanobench_srcs  = {s for s in nanobench_srcs if not s.endswith('.h')}
 
-# Only use the generated flags related to warnings.
-cflags          = {s for s in cflags         if s.startswith('-W')}
-cflags_cc       = {s for s in cflags_cc      if s.startswith('-W')}
-# Add the rest of the flags we want.
-cflags = cflags.union([
-    "-fvisibility=hidden",
-    "-D_FORTIFY_SOURCE=1",
-    "-DSKIA_DLL",
-    "-DSKIA_IMPLEMENTATION=1",
-    "-DATRACE_TAG=ATRACE_TAG_VIEW",
-    "-DSK_PRINT_CODEC_MESSAGES",
-])
-cflags_cc.add("-fexceptions")
-
-# We need to undefine FORTIFY_SOURCE before we define it. Insert it at the
-# beginning after sorting.
-cflags = sorted(cflags)
-cflags.insert(0, "-U_FORTIFY_SOURCE")
+cflags = gn_to_bp_utils.CleanupCFlags(cflags)
+cflags_cc = gn_to_bp_utils.CleanupCCFlags(cflags_cc)
 
 # We need to add the include path to the vulkan defines and header file set in
 # then skia_vulkan_header gn arg that is used for framework builds.
 local_includes.add("platform_tools/android/vulkan")
 export_includes.add("platform_tools/android/vulkan")
 
-# Most defines go into SkUserConfig.h, where they're seen by Skia and its users.
-defines = [str(d) for d in js['targets']['//:skia']['defines']]
-defines.remove('NDEBUG')                 # Let the Android build control this.
-defines.remove('SKIA_IMPLEMENTATION=1')  # Only libskia should have this define.
-
-# For architecture specific files, it's easier to just read the same source
-# that GN does (opts.gni) rather than re-run GN once for each architecture.
-
-# This .gni file we want to read is close enough to Python syntax
-# that we can use execfile() if we supply definitions for GN builtins.
-
-def get_path_info(path, kind):
-  assert kind == "abspath"
-  # While we want absolute paths in GN, relative paths work best here.
-  return path
-
-builtins = { 'get_path_info': get_path_info }
-defs = {}
 here = os.path.dirname(__file__)
-execfile(os.path.join(here,                      'opts.gni'), builtins, defs)
+defs = gn_to_bp_utils.GetArchSources(os.path.join(here, 'opts.gni'))
 
-# Turn paths from opts.gni into paths relative to external/skia.
-def scrub(lst):
-  # Perform any string substitutions.
-  for var in defs:
-    if type(defs[var]) is str:
-      lst = [ p.replace('$'+var, defs[var]) for p in lst ]
-  # Relativize paths to top-level skia/ directory.
-  return [os.path.relpath(p, '..') for p in lst]
+gn_to_bp_utils.WriteUserConfig('include/config/SkUserConfig.h', defines)
 
 # Turn a list of strings into the style bpfmt outputs.
 def bpfmt(indent, lst, sort=True):
@@ -327,16 +273,16 @@ with open('Android.bp', 'w') as f:
     'cflags':          bpfmt(8, cflags, False),
     'cflags_cc':       bpfmt(8, cflags_cc),
 
-    'arm_srcs':      bpfmt(16, scrub(defs['armv7'])),
-    'arm_neon_srcs': bpfmt(20, scrub(defs['neon'])),
-    'arm64_srcs':    bpfmt(16, scrub(defs['arm64'] +
-                                     defs['crc32'])),
-    'none_srcs':     bpfmt(16, scrub(defs['none'])),
-    'x86_srcs':      bpfmt(16, scrub(defs['sse2'] +
-                                     defs['ssse3'] +
-                                     defs['sse41'] +
-                                     defs['sse42'] +
-                                     defs['avx'  ])),
+    'arm_srcs':      bpfmt(16, defs['armv7']),
+    'arm_neon_srcs': bpfmt(20, defs['neon']),
+    'arm64_srcs':    bpfmt(16, defs['arm64'] +
+                               defs['crc32']),
+    'none_srcs':     bpfmt(16, defs['none']),
+    'x86_srcs':      bpfmt(16, defs['sse2'] +
+                               defs['ssse3'] +
+                               defs['sse41'] +
+                               defs['sse42'] +
+                               defs['avx'  ]),
 
     'dm_includes'       : bpfmt(8, dm_includes),
     'dm_srcs'           : bpfmt(8, dm_srcs),
@@ -344,14 +290,3 @@ with open('Android.bp', 'w') as f:
     'nanobench_includes'    : bpfmt(8, nanobench_includes),
     'nanobench_srcs'        : bpfmt(8, nanobench_srcs),
   })
-
-#... and all the #defines we want to put in SkUserConfig.h.
-with open('include/config/SkUserConfig.h', 'w') as f:
-  print >>f, '// DO NOT MODIFY! This file is autogenerated by gn_to_bp.py.'
-  print >>f, '// If need to change a define, modify SkUserConfigManual.h'
-  print >>f, '#ifndef SkUserConfig_DEFINED'
-  print >>f, '#define SkUserConfig_DEFINED'
-  print >>f, '#include "SkUserConfigManual.h"'
-  for define in sorted(defines):
-    print >>f, '  #define', define.replace('=', ' ')
-  print >>f, '#endif//SkUserConfig_DEFINED'
diff --git a/gn/gn_to_bp_utils.py b/gn/gn_to_bp_utils.py
new file mode 100644
index 0000000000..65456408cd
--- /dev/null
+++ b/gn/gn_to_bp_utils.py
@@ -0,0 +1,107 @@
+#!/usr/bin/env python
+#
+# Copyright 2018 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# Generate Android.bp for Skia from GN configuration.
+
+import argparse
+import json
+import os
+import pprint
+import string
+import subprocess
+import tempfile
+
+parser = argparse.ArgumentParser(description='Process some cmdline flags.')
+parser.add_argument('--gn', dest='gn_cmd', default='gn')
+args = parser.parse_args()
+
+def GenerateJSONFromGN(gn_args):
+  gn_args = ' '.join(sorted('%s=%s' % (k,v) for (k,v) in gn_args.iteritems()))
+  tmp = tempfile.mkdtemp()
+  subprocess.check_call([args.gn_cmd, 'gen', tmp, '--args=%s' % gn_args,
+                         '--ide=json'])
+  return json.load(open(os.path.join(tmp, 'project.json')))
+
+def _strip_slash(lst):
+  return {str(p.lstrip('/')) for p in lst}
+
+def GrabDependentValues(js, name, value_type, list_to_extend, exclude):
+  # Grab the values from other targets that $name depends on (e.g. optional
+  # Skia components, gms, tests, etc).
+  for dep in js['targets'][name]['deps']:
+    if 'third_party' in dep:
+      continue   # We've handled all third-party DEPS as static or shared_libs.
+    if 'none' in dep:
+      continue   # We'll handle all cpu-specific sources manually later.
+    if exclude and exclude in dep:
+      continue
+    list_to_extend.update(_strip_slash(js['targets'][dep].get(value_type, [])))
+    GrabDependentValues(js, dep, value_type, list_to_extend, exclude)
+
+def CleanupCFlags(cflags):
+  # Only use the generated flags related to warnings.
+  cflags = {s for s in cflags if s.startswith('-W')}
+  # Add the rest of the flags we want.
+  cflags = cflags.union([
+    "-fvisibility=hidden",
+    "-D_FORTIFY_SOURCE=1",
+    "-DSKIA_DLL",
+    "-DSKIA_IMPLEMENTATION=1",
+    "-DATRACE_TAG=ATRACE_TAG_VIEW",
+    "-DSK_PRINT_CODEC_MESSAGES",
+  ])
+
+  # We need to undefine FORTIFY_SOURCE before we define it. Insert it at the
+  # beginning after sorting.
+  cflags = sorted(cflags)
+  cflags.insert(0, "-U_FORTIFY_SOURCE")
+  return cflags
+
+def CleanupCCFlags(cflags_cc):
+  # Only use the generated flags related to warnings.
+  cflags_cc       = {s for s in cflags_cc      if s.startswith('-W')}
+  # Add the rest of the flags we want.
+  cflags_cc.add("-fexceptions")
+  return cflags_cc
+
+def _get_path_info(path, kind):
+  assert path == "../src"
+  assert kind == "abspath"
+  # While we want absolute paths in GN, relative paths work best here.
+  return "src"
+
+def GetArchSources(opts_file):
+  # For architecture specific files, it's easier to just read the same source
+  # that GN does (opts.gni) rather than re-run GN once for each architecture.
+
+  # This .gni file we want to read is close enough to Python syntax
+  # that we can use execfile() if we supply definitions for GN builtins.
+  builtins = { 'get_path_info': _get_path_info }
+  defs = {}
+  execfile(opts_file, builtins, defs)
+
+  # Perform any string substitutions.
+  for arch in defs:
+    defs[arch] = [ p.replace('$_src', 'src') for p in defs[arch]]
+
+  return defs
+
+def WriteUserConfig(userConfigPath, defines):
+  # Most defines go into SkUserConfig.h
+  defines.remove('NDEBUG')                 # Controlled by the Android build
+  defines.remove('SKIA_IMPLEMENTATION=1')  # don't export this define.
+
+  #... and all the #defines we want to put in SkUserConfig.h.
+  with open(userConfigPath, 'w') as f:
+    print >>f, '// DO NOT MODIFY! This file is autogenerated by gn_to_bp.py.'
+    print >>f, '// If need to change a define, modify SkUserConfigManual.h'
+    print >>f, '#ifndef SkUserConfig_DEFINED'
+    print >>f, '#define SkUserConfig_DEFINED'
+    print >>f, '#include "SkUserConfigManual.h"'
+    for define in sorted(defines):
+      print >>f, '  #define', define.replace('=', ' ')
+    print >>f, '#endif//SkUserConfig_DEFINED'
diff --git a/tools/skqp/gn_to_bp.py b/tools/skqp/gn_to_bp.py
new file mode 100644
index 0000000000..5f0ac9a26b
--- /dev/null
+++ b/tools/skqp/gn_to_bp.py
@@ -0,0 +1,213 @@
+#!/usr/bin/env python
+#
+# Copyright 2016 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# Generate Android.bp for Skia from GN configuration.
+
+import argparse
+import json
+import os
+import pprint
+import string
+import subprocess
+import sys
+import tempfile
+
+root_dir = os.path.join(os.path.dirname(os.path.abspath(__file__)),
+                        os.pardir, os.pardir)
+skia_gn_dir = os.path.join(root_dir, 'gn')
+sys.path.insert(0, skia_gn_dir)
+
+import gn_to_bp_utils
+
+# First we start off with a template for Android.bp,
+# with holes for source lists and include directories.
+bp = string.Template('''// This file is autogenerated by tools/skqp/gn_to_bp.py.
+
+cc_library_shared {
+    name: "libskqp_app",
+    sdk_version: "26",
+    stl: "libc++_static",
+    tags: ["tests", "optional"],
+
+    cflags: [
+        $cflags
+        "-Wno-unused-parameter",
+        "-Wno-unused-variable",
+    ],
+
+    cppflags:[
+        $cflags_cc
+    ],
+
+    local_include_dirs: [
+        $local_includes
+    ],
+
+    srcs: [
+        $srcs
+    ],
+
+    arch: {
+        arm: {
+            srcs: [
+                $arm_srcs
+            ],
+
+            neon: {
+                srcs: [
+                    $arm_neon_srcs
+                ],
+            },
+        },
+
+        arm64: {
+            srcs: [
+                $arm64_srcs
+            ],
+        },
+
+        mips: {
+            srcs: [
+                $none_srcs
+            ],
+        },
+
+        mips64: {
+            srcs: [
+                $none_srcs
+            ],
+        },
+
+        x86: {
+            srcs: [
+                $x86_srcs
+            ],
+            cflags: [
+                // Clang seems to think new/malloc will only be 4-byte aligned
+                // on x86 Android. We're pretty sure it's actually 8-byte
+                // alignment. tests/OverAlignedTest.cpp has more information,
+                // and should fail if we're wrong.
+                "-Wno-over-aligned"
+            ],
+        },
+
+        x86_64: {
+            srcs: [
+                $x86_srcs
+            ],
+        },
+    },
+
+    shared_libs: [
+          "libandroid",
+          "libEGL",
+          "libGLESv2",
+          "liblog",
+          "libvulkan",
+          "libz",
+    ],
+    static_libs: [
+          "libjpeg_static_ndk",
+          "libjsoncpp",
+          "libpng_ndk",
+          "libwebp-decode",
+          "libwebp-encode",
+    ]
+}''')
+
+# We'll run GN to get the main source lists and include directories for Skia.
+gn_args = {
+  'is_debug':   'false',
+  'target_cpu': '"none"',
+  'target_os':  '"android"',
+  'ndk_api':    '26',
+
+  # setup vulkan
+  'skia_use_vulkan':    'true',
+  'skia_vulkan_header': '"Skia_Vulkan_Android.h"',
+
+  # enable/disable skia subsystems
+  'skia_enable_fontmgr_empty': 'true',
+  'skia_enable_pdf':           'false',
+  'skia_use_expat':            'false',
+  'skia_use_dng_sdk':          'false',
+  'skia_use_icu':              'false',
+  'skia_use_lua':              'false',
+  'skia_use_piex':             'false',
+  'skia_use_skcms':            'false',
+
+  # specify that the Android.bp will supply the necessary components
+  'skia_use_system_expat':         'true', # removed this when gn is fixed
+  'skia_use_system_libpng':        'true',
+  'skia_use_system_jsoncpp':       'true',
+  'skia_use_system_libwebp':       'true',
+  'skia_use_system_libjpeg_turbo': 'true',
+  'skia_use_system_zlib':          'true',
+}
+
+js = gn_to_bp_utils.GenerateJSONFromGN(gn_args)
+
+def strip_slashes(lst):
+  return {str(p.lstrip('/')) for p in lst}
+
+srcs            = strip_slashes(js['targets']['//:libskqp_app']['sources'])
+cflags          = strip_slashes(js['targets']['//:libskqp_app']['cflags'])
+cflags_cc       = strip_slashes(js['targets']['//:libskqp_app']['cflags_cc'])
+local_includes  = strip_slashes(js['targets']['//:libskqp_app']['include_dirs'])
+defines      = {str(d) for d in js['targets']['//:libskqp_app']['defines']}
+
+gn_to_bp_utils.GrabDependentValues(js, '//:libskqp_app', 'sources', srcs, None)
+gn_to_bp_utils.GrabDependentValues(js, '//:libskqp_app', 'include_dirs',
+                                   local_includes, 'freetype')
+gn_to_bp_utils.GrabDependentValues(js, '//:libskqp_app', 'defines',
+                                   defines, None)
+
+# No need to list headers or other extra flags.
+srcs = {s for s in srcs           if not s.endswith('.h')}
+cflags = gn_to_bp_utils.CleanupCFlags(cflags)
+cflags_cc = gn_to_bp_utils.CleanupCCFlags(cflags_cc)
+
+# We need to add the include path to the vulkan defines and header file set in
+# then skia_vulkan_header gn arg that is used for framework builds.
+local_includes.add("platform_tools/android/vulkan")
+
+# Get architecture specific source files
+defs = gn_to_bp_utils.GetArchSources(os.path.join(skia_gn_dir, 'opts.gni'))
+
+# Add source file until fix lands in
+# https://skia-review.googlesource.com/c/skia/+/101820
+srcs.add("src/ports/SkFontMgr_empty_factory.cpp")
+
+# Turn a list of strings into the style bpfmt outputs.
+def bpfmt(indent, lst, sort=True):
+  if sort:
+    lst = sorted(lst)
+  return ('\n' + ' '*indent).join('"%s",' % v for v in lst)
+
+# Most defines go into SkUserConfig.h, where they're seen by Skia and its users.
+gn_to_bp_utils.WriteUserConfig('include/config/SkUserConfig.h', defines)
+
+# OK!  We have everything to fill in Android.bp...
+with open('Android.bp', 'w') as f:
+  print >>f, bp.substitute({
+    'local_includes': bpfmt(8, local_includes),
+    'srcs':           bpfmt(8, srcs),
+    'cflags':         bpfmt(8, cflags, False),
+    'cflags_cc':      bpfmt(8, cflags_cc),
+
+    'arm_srcs':       bpfmt(16, defs['armv7']),
+    'arm_neon_srcs':  bpfmt(20, defs['neon']),
+    'arm64_srcs':     bpfmt(16, defs['arm64'] +
+                                defs['crc32']),
+    'none_srcs':      bpfmt(16, defs['none']),
+    'x86_srcs':       bpfmt(16, defs['sse2'] +
+                                defs['ssse3'] +
+                                defs['sse41'] +
+                                defs['sse42'] +
+                                defs['avx'  ]),
+  })
+