[PATCH] cache.h: avoid deprecation warnings on OS X 10.8

[David Aguilar <davvid@gmail.com>]

Mac OS X Mountain Lion prints warnings when building git:

	warning: 'SHA1_Init' is deprecated
	(declared at /usr/include/openssl/sha.h:121)

Silence the warnings by using the Common Digest SHA-1
functions for SHA1_Init(), SHA1_Update(), and SHA1_Final().

Add a COMMON_DIGEST_SHA1 knob to the Makefile to allow
choosing this implementation and define it by default on Darwin.

Signed-off-by: David Aguilar <davvid@gmail.com>
---
This implements the suggestion from John Keeping instead
of blindly setting NO_OPENSSL on Darwin.

 Makefile | 4 ++++
 cache.h  | 6 ++++++
 2 files changed, 10 insertions(+)

diff --git a/Makefile b/Makefile
index 0f931a2..ce62002 100644
--- a/Makefile
+++ b/Makefile
@@ -1054,6 +1054,7 @@ ifeq ($(uname_S),Darwin)
 			BASIC_LDFLAGS += -L/opt/local/lib
 		endif
 	endif
+	COMMON_DIGEST_SHA1 = YesPlease
 	PTHREAD_LIBS =
 endif
 
@@ -1390,6 +1391,9 @@ ifdef PPC_SHA1
 else
 	SHA1_HEADER = <openssl/sha.h>
 	EXTLIBS += $(LIB_4_CRYPTO)
+ifdef COMMON_DIGEST_SHA1
+	BASIC_CFLAGS += -DCOMMON_DIGEST_FOR_SHA1=1
+endif
 endif
 endif
 ifdef NO_PERL_MAKEMAKER
diff --git a/cache.h b/cache.h
index 94ca1ac..f137fd4 100644
--- a/cache.h
+++ b/cache.h
@@ -11,10 +11,16 @@
 #include SHA1_HEADER
 #ifndef git_SHA_CTX
 #define git_SHA_CTX	SHA_CTX
+#ifdef COMMON_DIGEST_FOR_SHA1
+#define git_SHA1_Init	CC_SHA1_Init
+#define git_SHA1_Update	CC_SHA1_Update
+#define git_SHA1_Final	CC_SHA1_Final
+#else
 #define git_SHA1_Init	SHA1_Init
 #define git_SHA1_Update	SHA1_Update
 #define git_SHA1_Final	SHA1_Final
 #endif
+#endif
 
 #include <zlib.h>
 typedef struct git_zstream {
-- 
1.8.3.rc1.44.gb387c77.dirty