Define compat version of mkdtemp for systems lacking it

Solaris 9 doesn't have mkdtemp() so we need to emulate it for the
rsync transport implementation.  Since Solaris 9 is lacking this
function we can also reasonably assume it is not available on
Solaris 8 either.  The new Makfile definition NO_MKDTEMP can be
set to enable the git compat version.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

Makefile

@@ -38,6 +38,8 @@ all::
 #
 # Define NO_SETENV if you don't have setenv in the C library.
 #
+# Define NO_MKDTEMP if you don't have mkdtemp in the C library.
+#
 # Define NO_SYMLINK_HEAD if you never want .git/HEAD to be a symbolic link.
 # Enable it on Windows.  By default, symrefs are still used.
 #
@@ -414,12 +416,14 @@ ifeq ($(uname_S),SunOS)
 		NEEDS_LIBICONV = YesPlease
 		NO_UNSETENV = YesPlease
 		NO_SETENV = YesPlease
+		NO_MKDTEMP = YesPlease
 		NO_C99_FORMAT = YesPlease
 		NO_STRTOUMAX = YesPlease
 	endif
 	ifeq ($(uname_R),5.9)
 		NO_UNSETENV = YesPlease
 		NO_SETENV = YesPlease
+		NO_MKDTEMP = YesPlease
 		NO_C99_FORMAT = YesPlease
 		NO_STRTOUMAX = YesPlease
 	endif
@@ -610,6 +614,10 @@ ifdef NO_SETENV
 	COMPAT_CFLAGS += -DNO_SETENV
 	COMPAT_OBJS += compat/setenv.o
 endif
+ifdef NO_MKDTEMP
+	COMPAT_CFLAGS += -DNO_MKDTEMP
+	COMPAT_OBJS += compat/mkdtemp.o
+endif
 ifdef NO_UNSETENV
 	COMPAT_CFLAGS += -DNO_UNSETENV
 	COMPAT_OBJS += compat/unsetenv.o

compat/mkdtemp.c

@@ -0,0 +1,8 @@
+#include "../git-compat-util.h"
+
+char *gitmkdtemp(char *template)
+{
+	if (!mktemp(template) || mkdir(template, 0700))
+		return NULL;
+	return template;
+}

git-compat-util.h

@@ -147,6 +147,11 @@ extern ssize_t git_pread(int fd, void *buf, size_t count, off_t offset);
 extern int gitsetenv(const char *, const char *, int);
 #endif
 
+#ifdef NO_MKDTEMP
+#define mkdtemp gitmkdtemp
+extern char *gitmkdtemp(char *);
+#endif
+
 #ifdef NO_UNSETENV
 #define unsetenv gitunsetenv
 extern void gitunsetenv(const char *);