add support for the SUA layer (interix; windows)

* add required build options to Makefile.
* introduce new NO_INTTYPES_H for systems lacking inttypes; code
  includes stdint.h instead, if this is set.
* introduce new NO_SYS_POLL_H for systems lacking sys/poll.h; code
  includes poll.h instead, if this is set.
* introduce NO_INITGROUPS. initgroups() call is simply omitted.

Signed-off-by: Markus Duft <mduft@gentoo.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Makefile

@@ -1096,6 +1096,25 @@ else
 endif
 	X = .exe
 endif
+ifeq ($(uname_S),Interix)
+	NO_SYS_POLL_H = YesPlease
+	NO_INTTYPES_H = YesPlease
+	NO_INITGROUPS = YesPlease
+	NO_IPV6 = YesPlease
+	NO_MEMMEM = YesPlease
+	NO_MKDTEMP = YesPlease
+	NO_STRTOUMAX = YesPlease
+	NO_NSEC = YesPlease
+	NO_MKSTEMPS = YesPlease
+	ifeq ($(uname_R),3.5)
+		NO_INET_NTOP = YesPlease
+		NO_INET_PTON = YesPlease
+	endif
+	ifeq ($(uname_R),5.2)
+		NO_INET_NTOP = YesPlease
+		NO_INET_PTON = YesPlease
+	endif
+endif
 ifneq (,$(findstring MINGW,$(uname_S)))
 	pathsep = ;
 	NO_PREAD = YesPlease
@@ -1360,6 +1379,15 @@ endif
 ifdef NO_SYS_SELECT_H
 	BASIC_CFLAGS += -DNO_SYS_SELECT_H
 endif
+ifdef NO_SYS_POLL_H
+	BASIC_CFLAGS += -DNO_SYS_POLL_H
+endif
+ifdef NO_INTTYPES_H
+	BASIC_CFLAGS += -DNO_INTTYPES_H
+endif
+ifdef NO_INITGROUPS
+	BASIC_CFLAGS += -DNO_INITGROUPS
+endif
 ifdef NO_MMAP
 	COMPAT_CFLAGS += -DNO_MMAP
 	COMPAT_OBJS += compat/mmap.o

daemon.c

@@ -15,6 +15,10 @@
 #define NI_MAXSERV 32
 #endif
 
+#ifdef NO_INITGROUPS
+#define initgroups(x, y) (0) /* nothing */
+#endif
+
 static int log_syslog;
 static int verbose;
 static int reuseaddr;

git-compat-util.h

@@ -106,7 +106,11 @@
 #include <utime.h>
 #ifndef __MINGW32__
 #include <sys/wait.h>
+#ifndef NO_SYS_POLL_H
 #include <sys/poll.h>
+#else
+#include <poll.h>
+#endif
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <termios.h>
@@ -118,7 +122,11 @@
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <pwd.h>
+#ifndef NO_INTTYPES_H
 #include <inttypes.h>
+#else
+#include <stdint.h>
+#endif
 #if defined(__CYGWIN__)
 #undef _XOPEN_SOURCE
 #include <grp.h>