Makefile: always provide a fallback when hardlinks fail

We make hardlinks from "git" to "git-<cmd>" built-ins and have been
careful to avoid cross-device links when linking "git-<cmd>" to
gitexecdir.

However, we were not prepared to deal with a build directory that is
incapable of making hard links within itself. This patch corrects it.

Instead of temporarily linking "git" to gitexecdir, directly link "git-
add", falling back to "cp". Try hardlinking that as "git-<cmd>", falling
back to symlinks or "cp" on error.

While at it, avoid 100+ error messages from hardlink failures when we are
going to fall back to symlinks or "cp" by redirecting the standard error
to /dev/null.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Makefile b/Makefile
index 2cef0187d1d28ef2b466c1231499409f5cc1532f..588bf5aee5763a1e55aa6878166539987f83ec9f 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1099,7 +1099,10 @@ help.o: help.c common-cmds.h GIT-CFLAGS
                '-DGIT_INFO_PATH="$(infodir_SQ)"' $<
 
 $(BUILT_INS): git$X
-       $(QUIET_BUILT_IN)$(RM) $@ && ln git$X $@
+       $(QUIET_BUILT_IN)$(RM) $@ && \
+       ln git$X $@ 2>/dev/null || \
+       ln -s git$X $@ 2>/dev/null || \
+       cp git$X $@
 
 common-cmds.h: ./generate-cmdlist.sh command-list.txt
 
@@ -1364,16 +1367,13 @@ ifneq (,$X)
 endif
        bindir=$$(cd '$(DESTDIR_SQ)$(bindir_SQ)' && pwd) && \
        execdir=$$(cd '$(DESTDIR_SQ)$(gitexec_instdir_SQ)' && pwd) && \
-       if test "z$$bindir" != "z$$execdir"; \
-       then \
-               ln -f "$$bindir/git$X" "$$execdir/git$X" || \
-               cp "$$bindir/git$X" "$$execdir/git$X"; \
-       fi && \
-       { $(foreach p,$(BUILT_INS), $(RM) "$$execdir/$p" && ln "$$execdir/git$X" "$$execdir/$p" ;) } && \
-       if test "z$$bindir" != "z$$execdir"; \
-       then \
-               $(RM) "$$execdir/git$X"; \
-       fi && \
+       { $(RM) "$$execdir/git-add$X" && \
+               ln git-add$X "$$execdir/git-add$X" 2>/dev/null || \
+               cp git-add$X "$$execdir/git-add$X"; } && \
+       { $(foreach p,$(filter-out git-add,$(BUILT_INS)), $(RM) "$$execdir/$p" && \
+               ln "$$execdir/git-add$X" "$$execdir/$p" 2>/dev/null || \
+               ln -s "git-add$X" "$$execdir/$p" 2>/dev/null || \
+               cp "$$execdir/git-add$X" "$$execdir/$p" || exit;) } && \
        ./check_bindir "z$$bindir" "z$$execdir" "$$bindir/git-add$X"
 
 install-doc: