wrapper: make inclusion of Windows csprng header tightly scoped

Including NTSecAPI.h in git-compat-util.h causes build errors in any
other file that includes winternl.h. NTSecAPI.h was included in order to
get access to the RtlGenRandom cryptographically secure PRNG. This
change scopes the inclusion of ntsecapi.h to wrapper.c, which is the only
place that it's actually needed.

The build breakage is due to the definition of UNICODE_STRING in
NtSecApi.h:
    #ifndef _NTDEF_
    typedef LSA_UNICODE_STRING UNICODE_STRING, *PUNICODE_STRING;
    typedef LSA_STRING STRING, *PSTRING ;
    #endif

LsaLookup.h:
    typedef struct _LSA_UNICODE_STRING {
        USHORT Length;
        USHORT MaximumLength;
    #ifdef MIDL_PASS
        [size_is(MaximumLength/2), length_is(Length/2)]
    #endif // MIDL_PASS
        PWSTR  Buffer;
    } LSA_UNICODE_STRING, *PLSA_UNICODE_STRING;

winternl.h also defines UNICODE_STRING:
    typedef struct _UNICODE_STRING {
        USHORT Length;
        USHORT MaximumLength;
        PWSTR  Buffer;
    } UNICODE_STRING;
    typedef UNICODE_STRING *PUNICODE_STRING;

Both definitions have equivalent layouts. Apparently these internal
Windows headers aren't designed to be included together. This is
an oversight in the headers and does not represent an incompatibility
between the APIs.

Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/compat/winansi.c b/compat/winansi.c
index 936a80a5f007d4d6e764f6dc68d649ea1e72094e..3abe8dd5a2711b5268cb5efe623d8c027f0d3d83 100644 (file)
--- a/compat/winansi.c
+++ b/compat/winansi.c
@@ -4,11 +4,6 @@
 
 #undef NOGDI
 
-/*
- * Including the appropriate header file for RtlGenRandom causes MSVC to see a
- * redefinition of types in an incompatible way when including headers below.
- */
-#undef HAVE_RTLGENRANDOM
 #include "../git-compat-util.h"
 #include <wingdi.h>
 #include <winreg.h>

diff --git a/git-compat-util.h b/git-compat-util.h
index 876907b9df4461059422797aea45385bf1d05de9..d210cff058c9aa92549b42ed90613143ac9347cb 100644 (file)
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -197,12 +197,6 @@
 #endif
 #include <windows.h>
 #define GIT_WINDOWS_NATIVE
-#ifdef HAVE_RTLGENRANDOM
-/* This is required to get access to RtlGenRandom. */
-#define SystemFunction036 NTAPI SystemFunction036
-#include <NTSecAPI.h>
-#undef SystemFunction036
-#endif
 #endif
 
 #include <unistd.h>

diff --git a/wrapper.c b/wrapper.c
index 3258cdb171f5181b869f547a607a5e35733333c8..1108e4840a4f501e57c6beb4c5e151f86f518f06 100644 (file)
--- a/wrapper.c
+++ b/wrapper.c
@@ -4,6 +4,13 @@
 #include "cache.h"
 #include "config.h"
 
+#ifdef HAVE_RTLGENRANDOM
+/* This is required to get access to RtlGenRandom. */
+#define SystemFunction036 NTAPI SystemFunction036
+#include <NTSecAPI.h>
+#undef SystemFunction036
+#endif
+
 static int memory_limit_check(size_t size, int gentle)
 {
        static size_t limit = 0;