[PATCH v3] Replace hard-coded path with one from <paths.h>

[Chris Webb <chris@arachsys.com>]

In exec_cmd.c, git hard-codes a default path of /usr/local/bin:/usr/bin:/bin.
Get an appropriate value for the system from <paths.h> if possible instead. We
only try to include <paths.h> on Linux, FreeBSD, NetBSD, OpenBSD and GNU where
it is known to exist.

Signed-off-by: Chris Webb <chris@arachsys.com>
---
 Makefile          |   10 ++++++++++
 exec_cmd.c        |    2 +-
 git-compat-util.h |    6 ++++++
 3 files changed, 17 insertions(+), 1 deletions(-)

diff --git a/Makefile b/Makefile
index 910f471..f4fe941 100644
--- a/Makefile
+++ b/Makefile
@@ -735,10 +735,12 @@ EXTLIBS =
 ifeq ($(uname_S),Linux)
 	NO_STRLCPY = YesPlease
 	NO_MKSTEMPS = YesPlease
+	HAVE_PATHS_H = YesPlease
 endif
 ifeq ($(uname_S),GNU/kFreeBSD)
 	NO_STRLCPY = YesPlease
 	NO_MKSTEMPS = YesPlease
+	HAVE_PATHS_H = YesPlease
 endif
 ifeq ($(uname_S),UnixWare)
 	CC = cc
@@ -867,6 +869,7 @@ ifeq ($(uname_S),FreeBSD)
 		NO_STRTOUMAX = YesPlease
 	endif
 	PYTHON_PATH = /usr/local/bin/python
+	HAVE_PATHS_H = YesPlease
 endif
 ifeq ($(uname_S),OpenBSD)
 	NO_STRCASESTR = YesPlease
@@ -875,6 +878,7 @@ ifeq ($(uname_S),OpenBSD)
 	NEEDS_LIBICONV = YesPlease
 	BASIC_CFLAGS += -I/usr/local/include
 	BASIC_LDFLAGS += -L/usr/local/lib
+	HAVE_PATHS_H = YesPlease
 endif
 ifeq ($(uname_S),NetBSD)
 	ifeq ($(shell expr "$(uname_R)" : '[01]\.'),2)
@@ -884,6 +888,7 @@ ifeq ($(uname_S),NetBSD)
 	BASIC_LDFLAGS += -L/usr/pkg/lib $(CC_LD_DYNPATH)/usr/pkg/lib
 	USE_ST_TIMESPEC = YesPlease
 	NO_MKSTEMPS = YesPlease
+	HAVE_PATHS_H = YesPlease
 endif
 ifeq ($(uname_S),AIX)
 	NO_STRCASESTR=YesPlease
@@ -904,6 +909,7 @@ ifeq ($(uname_S),GNU)
 	# GNU/Hurd
 	NO_STRLCPY=YesPlease
 	NO_MKSTEMPS = YesPlease
+	HAVE_PATHS_H = YesPlease
 endif
 ifeq ($(uname_S),IRIX)
 	NO_SETENV = YesPlease
@@ -1353,6 +1359,10 @@ else
 	LIB_OBJS += thread-utils.o
 endif
 
+ifdef HAVE_PATHS_H
+	BASIC_CFLAGS += -DHAVE_PATHS_H
+endif
+
 ifdef DIR_HAS_BSD_GROUP_SEMANTICS
 	COMPAT_CFLAGS += -DDIR_HAS_BSD_GROUP_SEMANTICS
 endif
diff --git a/exec_cmd.c b/exec_cmd.c
index b2c07c7..bf22570 100644
--- a/exec_cmd.c
+++ b/exec_cmd.c
@@ -107,7 +107,7 @@ void setup_path(void)
 	if (old_path)
 		strbuf_addstr(&new_path, old_path);
 	else
-		strbuf_addstr(&new_path, "/usr/local/bin:/usr/bin:/bin");
+		strbuf_addstr(&new_path, _PATH_DEFPATH);
 
 	setenv("PATH", new_path.buf, 1);
 
diff --git a/git-compat-util.h b/git-compat-util.h
index 7e62b55..ed1accc 100644
--- a/git-compat-util.h
+++ b/git-compat-util.h
@@ -164,6 +164,12 @@ extern char *gitbasename(char *);
 #define PATH_SEP ':'
 #endif
 
+#ifdef HAVE_PATHS_H
+#include <paths.h>
+#else
+#define _PATH_DEFPATH "/usr/local/bin:/usr/bin:/bin"
+#endif
+
 #ifndef STRIP_EXTENSION
 #define STRIP_EXTENSION ""
 #endif
-- 
1.7.0.3