From 07d66af3b0800764087c4151d4f6562d4f8cce05 Mon Sep 17 00:00:00 2001
From: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Date: Mon, 14 Dec 2020 23:00:33 +0100
Subject: [PATCH] Fix build without threads

Build without threads is broken since version 2.29.0 and
https://github.com/git/git/commit/15b52a44e0c92a0658e891194a5b0610d1f53afc:

In file included from cache.h:4,
                 from blame.c:1:
git-compat-util.h:1238:20: error: static declaration of 'flockfile' follows non-static declaration
 static inline void flockfile(FILE *fh)
                    ^~~~~~~~~
In file included from git-compat-util.h:168,
                 from cache.h:4,
                 from blame.c:1:
/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/arm-buildroot-linux-uclibcgnueabihf/sysroot/usr/include/stdio.h:806:13: note: previous declaration of 'flockfile' was here
 extern void flockfile (FILE *__stream) __THROW;
             ^~~~~~~~~
In file included from cache.h:4,
                 from blame.c:1:
git-compat-util.h:1242:20: error: static declaration of 'funlockfile' follows non-static declaration
 static inline void funlockfile(FILE *fh)
                    ^~~~~~~~~~~
In file included from git-compat-util.h:168,
                 from cache.h:4,
                 from blame.c:1:
/nvme/rc-buildroot-test/scripts/instance-0/output-1/host/arm-buildroot-linux-uclibcgnueabihf/sysroot/usr/include/stdio.h:813:13: note: previous declaration of 'funlockfile' was here
 extern void funlockfile (FILE *__stream) __THROW;
             ^~~~~~~~~~~

To avoid this build failure, check if flockfile is available before
defining flockfile, funlockfile and getc_unlocked

Fixes:
 - http://autobuild.buildroot.org/results/d41638d1ad8e78dd6f654367c905996b838ee649

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
---
 Makefile          | 5 +++++
 configure.ac      | 6 ++++++
 git-compat-util.h | 2 +-
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 6fb86c5862..58d0893a12 100644
--- a/Makefile
+++ b/Makefile
@@ -232,6 +232,8 @@ all::
 # Define NO_STRUCT_ITIMERVAL if you don't have struct itimerval
 # This also implies NO_SETITIMER
 #
+# Define NO_FLOCKFILE if you don't have flockfile()
+#
 # Define NO_FAST_WORKING_DIRECTORY if accessing objects in pack files is
 # generally faster on your platform than accessing the working directory.
 #
@@ -1638,6 +1640,9 @@ endif
 ifdef NO_SETITIMER
 	COMPAT_CFLAGS += -DNO_SETITIMER
 endif
+ifdef NO_FLOCKFILE
+	COMPAT_CFLAGS += -DNO_FLOCKFILE
+endif
 ifdef NO_PREAD
 	COMPAT_CFLAGS += -DNO_PREAD
 	COMPAT_OBJS += compat/pread.o
diff --git a/configure.ac b/configure.ac
index 66aedb9288..d4295b5c69 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1132,6 +1132,12 @@ GIT_CHECK_FUNC(setitimer,
 [NO_SETITIMER=YesPlease])
 GIT_CONF_SUBST([NO_SETITIMER])
 #
+# Define NO_FLOCKFILE if you don't have flockfile.
+GIT_CHECK_FUNC(flockfile,
+[NO_FLOCKFILE=],
+[NO_FLOCKFILE=YesPlease])
+GIT_CONF_SUBST([NO_FLOCKFILE])
+#
 # Define NO_STRCASESTR if you don't have strcasestr.
 GIT_CHECK_FUNC(strcasestr,
 [NO_STRCASESTR=],
diff --git a/git-compat-util.h b/git-compat-util.h
index 7d509c5022..279cdd941e 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -1236,7 +1236,7 @@ int warn_on_fopen_errors(const char *path);
 # define SHELL_PATH "/bin/sh"
 #endif
 
-#ifndef _POSIX_THREAD_SAFE_FUNCTIONS
+#if !defined(_POSIX_THREAD_SAFE_FUNCTIONS) && defined(NO_FLOCKFILE)
 static inline void flockfile(FILE *fh)
 {
 	; /* nothing */
-- 
2.29.2