Linux: add option for building with system re2.

third_party/re2/re2.gyp

Index: third_party/re2/re2.gyp
diff --git a/third_party/re2/re2.gyp b/third_party/re2/re2.gyp
index fe11a6513d477d533b4d00472cd1055381cec80a..3c1afbedb3cac53e332b4e258c15483fbccf8b85 100644
--- a/third_party/re2/re2.gyp
+++ b/third_party/re2/re2.gyp
@@ -4,83 +4,113 @@
 
 {
   'variables': {
+    'use_system_re2%': 0,
   },
-  'targets': [
-    {
-      'target_name': 're2',
-      'type': 'static_library',
-      'include_dirs': [
-        '.',
-        '<(DEPTH)',
-      ],
-      'direct_dependent_settings': {
-        'include_dirs': [
-          '.',
-          '<(DEPTH)',
-        ],
-      },
-      'dependencies': [
-        '<(DEPTH)/base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
-      ],
-      'sources': [
-        're2/bitstate.cc',
-        're2/compile.cc',
-        're2/dfa.cc',
-        're2/filtered_re2.cc',
-        're2/filtered_re2.h',
-        're2/mimics_pcre.cc',
-        're2/nfa.cc',
-        're2/onepass.cc',
-        're2/parse.cc',
-        're2/perl_groups.cc',
-        're2/prefilter.cc',
-        're2/prefilter.h',
-        're2/prefilter_tree.cc',
-        're2/prefilter_tree.h',
-        're2/prog.cc',
-        're2/prog.h',
-        're2/re2.cc',
-        're2/re2.h',
-        're2/regexp.cc',
-        're2/regexp.h',
-        're2/set.cc',
-        're2/set.h',
-        're2/simplify.cc',
-        're2/stringpiece.h',
-        're2/tostring.cc',
-        're2/unicode_casefold.cc',
-        're2/unicode_casefold.h',
-        're2/unicode_groups.cc',
-        're2/unicode_groups.h',
-        're2/variadic_function.h',
-        're2/walker-inl.h',
-        'util/arena.cc',
-        'util/arena.h',
-        'util/atomicops.h',
-        'util/flags.h',
-        'util/hash.cc',
-        'util/logging.h',
-        'util/mutex.h',
-        'util/rune.cc',
-        'util/sparse_array.h',
-        'util/sparse_set.h',
-        'util/stringpiece.cc',
-        'util/stringprintf.cc',
-        'util/strutil.cc',
-        'util/utf.h',
-        'util/util.h',
-      ],
-      'conditions': [
-        ['OS=="win"', {
+  'conditions': [
+    ['use_system_re2==0', {
+      'targets': [
+        {
+          'target_name': 're2',
+          'type': 'static_library',
+          'include_dirs': [
+            '.',
+            '<(DEPTH)',
+          ],
+          'direct_dependent_settings': {
+            'include_dirs': [
+              '.',
+              '<(DEPTH)',
+            ],
+          },
+          'dependencies': [
+            '<(DEPTH)/base/third_party/dynamic_annotations/dynamic_annotations.gyp:dynamic_annotations',
+          ],
           'sources': [
-            'mswin/stdint.h'
+            're2/bitstate.cc',
+            're2/compile.cc',
+            're2/dfa.cc',
+            're2/filtered_re2.cc',
+            're2/filtered_re2.h',
+            're2/mimics_pcre.cc',
+            're2/nfa.cc',
+            're2/onepass.cc',
+            're2/parse.cc',
+            're2/perl_groups.cc',
+            're2/prefilter.cc',
+            're2/prefilter.h',
+            're2/prefilter_tree.cc',
+            're2/prefilter_tree.h',
+            're2/prog.cc',
+            're2/prog.h',
+            're2/re2.cc',
+            're2/re2.h',
+            're2/regexp.cc',
+            're2/regexp.h',
+            're2/set.cc',
+            're2/set.h',
+            're2/simplify.cc',
+            're2/stringpiece.h',
+            're2/tostring.cc',
+            're2/unicode_casefold.cc',
+            're2/unicode_casefold.h',
+            're2/unicode_groups.cc',
+            're2/unicode_groups.h',
+            're2/variadic_function.h',
+            're2/walker-inl.h',
+            'util/arena.cc',
+            'util/arena.h',
+            'util/atomicops.h',
+            'util/flags.h',
+            'util/hash.cc',
+            'util/logging.h',
+            'util/mutex.h',
+            'util/rune.cc',
+            'util/sparse_array.h',
+            'util/sparse_set.h',
+            'util/stringpiece.cc',
+            'util/stringprintf.cc',
+            'util/strutil.cc',
+            'util/utf.h',
+            'util/util.h',
           ],
-          'include_dirs': [
-            'mswin'
+          'conditions': [
+            ['OS=="win"', {
+              'sources': [
+                'mswin/stdint.h'
+              ],
+              'include_dirs': [
+                'mswin'
+              ],
+              'msvs_disabled_warnings': [ 4018, 4722 ],
+            }]
+          ]
+        },
+      ],
+    }, { # use_system_re2==1
+      'targets': [
+        {
+          'target_name': 're2',
+          'type': 'none',
+          'variables': {
+            'headers_root_path': '.',
+            'header_filenames': [
+              're2/filtered_re2.h',
+              're2/re2.h',
+              're2/set.h',
+              're2/stringpiece.h',
+              're2/variadic_function.h',

[Ryan Sleevi, 2013/01/03 00:38:35]

Can you explain why you do not need to handle prog.h, regexp.h,
prefilter_tree.h, or unicode_groups.h?

I'm just trying to figure out how you determined this set of headers to
represent the 'public' API for shim-ing.

[Paweł Hajdan Jr., 2013/01/03 01:05:43]

This is what re2 snapshot I have installed into /usr/include . Chrome might be
using a different snapshot. For now I'm fine with the list in this CL.

+            ],
+          },
+          'includes': [
+            '../../build/shim_headers.gypi',
           ],
-          'msvs_disabled_warnings': [ 4018, 4722 ],
-        }]
-      ]
-    },
+          'link_settings': {
+            'libraries': [
+              '-lre2',
+            ],
+          },
+        }
+      ],
+    }],
   ],
 }