Measure free space on Android using statfs()

Android.mk

@@ -29,7 +29,7 @@ SERVALD_LOCAL_CFLAGS = \
 	-DHAVE_JNI_H=1 -DHAVE_STRUCT_UCRED=1 -DHAVE_CRYPTO_SIGN_NACL_GE25519_H=1 \
         -DBYTE_ORDER=_BYTE_ORDER -DHAVE_LINUX_STRUCT_UCRED -DUSE_ABSTRACT_NAMESPACE \
         -DHAVE_BCOPY -DHAVE_BZERO -DHAVE_NETINET_IN_H -DHAVE_LSEEK64 -DSIZEOF_OFF_T=4 \
-        -DHAVE_LINUX_IF_H -DSQLITE_THREADSAFE=0 \
+        -DHAVE_LINUX_IF_H -DHAVE_SYS_STAT_H -DHAVE_SYS_VFS_H -DSQLITE_THREADSAFE=0 \
 	-I$(NACL_INC) \
 	-I$(SQLITE3_INC)
 

configure.in

@@ -93,6 +93,7 @@ AC_CHECK_HEADERS(
     sys/time.h \
     sys/ucred.h \
     sys/statvfs.h \
+    sys/stat.h \
     sys/vfs.h \
     poll.h \
     netdb.h \

rhizome_store.c

@@ -21,6 +21,12 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include <assert.h>
 #ifdef HAVE_SYS_STATVFS_H
 #  include <sys/statvfs.h>
+#else
+#  if defined(HAVE_SYS_STAT_H) && defined(HAVE_SYS_VFS_H)
+#    include <sys/stat.h>
+#    include <sys/vfs.h>
+#    define statvfs statfs
+#  endif
 #endif
 #include "serval.h"
 #include "rhizome.h"
@@ -158,7 +164,7 @@ static uint64_t store_get_free_space()
   const char *fake_space = getenv("SERVALD_FREE_SPACE");
   if (fake_space)
     return atol(fake_space);
-#ifdef HAVE_SYS_STATVFS_H
+#if defined(HAVE_SYS_STATVFS_H) || (defined(HAVE_SYS_STAT_H) && defined(HAVE_SYS_VFS_H))
   char store_path[1024];
   if (!FORMF_RHIZOME_STORE_PATH(store_path, "rhizome.db"))
     return UINT64_MAX;