[PATCH v3 2/4] Makefile: define THIRD_PARTY_SOURCES

[Denton Liu <liu.denton@gmail.com>]

Some files in our codebase are borrowed from other projects, and
minimally updated to suit our own needs. We'd sometimes need to tell
our own sources and these third-party sources apart for management
purposes (e.g. we may want to be less strict about coding style and
other issues on third-party files).

Define the $(MAKE) variable THIRD_PARTY_SOURCES that can be used to
match names of third-party sources.

Signed-off-by: Denton Liu <liu.denton@gmail.com>
---
 Makefile | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Makefile b/Makefile
index ea77198247..49839579ec 100644
--- a/Makefile
+++ b/Makefile
@@ -598,6 +598,7 @@ SCRIPT_SH =
 SCRIPT_LIB =
 TEST_BUILTINS_OBJS =
 TEST_PROGRAMS_NEED_X =
+THIRD_PARTY_SOURCES =
 
 # Having this variable in your environment would break pipelines because
 # you cause "cd" to echo its destination to stdout.  It can also take
@@ -1146,6 +1147,17 @@ BUILTIN_OBJS += builtin/verify-tag.o
 BUILTIN_OBJS += builtin/worktree.o
 BUILTIN_OBJS += builtin/write-tree.o
 
+# THIRD_PARTY_SOURCES is a list of patterns compatible with
+# the $(filter) and $(filter-out) family of functions
+THIRD_PARTY_SOURCES += compat/inet_ntop.c
+THIRD_PARTY_SOURCES += compat/inet_pton.c
+THIRD_PARTY_SOURCES += compat/obstack.%
+THIRD_PARTY_SOURCES += compat/nedmalloc/%
+THIRD_PARTY_SOURCES += compat/poll/%
+THIRD_PARTY_SOURCES += compat/regex/%
+THIRD_PARTY_SOURCES += sha1collisiondetection/%
+THIRD_PARTY_SOURCES += sha1dc/%
+
 GITLIBS = common-main.o $(LIB_FILE) $(XDIFF_LIB)
 EXTLIBS =
 
-- 
2.23.0