RE: [PATCH v4] Support for setitimer() on platforms lacking it

["Joachim Schmitz" <jojo@schmitz-digital.de>]

HP NonStop (currently) doesn't have setitimer().
As setitimer() is only used in cases of perceived latency and it doesn't affect
correctness, it gets disabled entirely if NO_SETITIMER is set.
HP NonStop does provide struct itimerval, but other platforms may not, so this
is taken care of in this commit too, by setting NO_STRUCT_ITIMERVAL.

Signed-off-by: Joachim Schmitz <jojo@schmitz-digital.de>
---
 Makefile          | 12 ++++++++++++
 git-compat-util.h | 11 +++++++++++
 2 files changed, 23 insertions(+), 0 deletions(-)

diff --git a/Makefile b/Makefile
index ac49320..7be555b 100644
--- a/Makefile
+++ b/Makefile
@@ -157,6 +157,11 @@ all::
 # Define NO_PREAD if you have a problem with pread() system call (e.g.
 # cygwin1.dll before v1.5.22).
 #
+# Define NO_SETITIMER if you don't have setitimer()
+#
+# Define NO_STRUCT_ITIMERVAL if you don't have struct itimerval
+# This also implies NO_SETITIMER
+#
 # Define NO_THREAD_SAFE_PREAD if your pread() implementation is not
 # thread-safe. (e.g. compat/pread.c or cygwin)
 #
@@ -1647,6 +1652,13 @@
 ifdef OBJECT_CREATION_USES_RENAMES
 	COMPAT_CFLAGS += -DOBJECT_CREATION_MODE=1
 endif
+ifdef NO_STRUCT_ITIMERVAL
+	COMPAT_CFLAGS += -DNO_STRUCT_ITIMERVAL
+	NO_SETITIMER=YesPlease
+endif
+ifdef NO_SETITIMER
+	COMPAT_CFLAGS += -DNO_SETITIMER
+endif
 ifdef NO_PREAD
 	COMPAT_CFLAGS += -DNO_PREAD
 	COMPAT_OBJS += compat/pread.o
diff --git a/git-compat-util.h b/git-compat-util.h
index 18089f0..4628d7a 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -162,6 +162,17 @@
 #define probe_utf8_pathname_composition(a,b)
 #endif
 
+#ifdef NO_STRUCT_ITIMERVAL
+struct itimerval {
+	struct timeval it_interval;
+	struct timeval it_value;
+}
+#endif
+
+#ifdef NO_SETITIMER
+#define setitimer(which,value,ovalue)
+#endif
+
 #ifdef MKDIR_WO_TRAILING_SLASH
 #define mkdir(a,b) compat_mkdir_wo_trailing_slash((a),(b))
 extern int compat_mkdir_wo_trailing_slash(const char*, mode_t);
-- 
1.7.12