[build] Adding Autoconf file

configure.ac

@@ -0,0 +1,54 @@
+#                                               -*- Autoconf -*-
+# Process this file with autoconf to produce a configure script.
+
+AC_PREREQ([2.69])
+AC_INIT([libpostal], [0.1])
+AM_INIT_AUTOMAKE([foreign subdir-objects])
+LT_PREREQ([2.2])
+LT_INIT([shared])
+AC_CONFIG_SRCDIR([src])
+AC_CONFIG_HEADERS([config.h])
+
+# Checks for programs.
+AC_PROG_CC_C99
+AC_PROG_INSTALL
+
+# Checks for libraries.
+AC_SEARCH_LIBS([snappy_compress],
+  [snappy],,[AC_MSG_ERROR([Could not find snappy])
+])
+
+# Checks for header files.
+AC_HEADER_STDC
+AC_CHECK_HEADERS([fcntl.h float.h inttypes.h limits.h locale.h malloc.h memory.h stddef.h stdint.h stdlib.h string.h sys/time.h unistd.h])
+
+# Checks for typedefs, structures, and compiler characteristics.
+AC_CHECK_HEADER_STDBOOL
+AC_C_INLINE
+AC_TYPE_INT16_T
+AC_TYPE_INT32_T
+AC_TYPE_INT64_T
+AC_TYPE_INT8_T
+AC_TYPE_OFF_T
+AC_TYPE_SIZE_T
+AC_TYPE_SSIZE_T
+AC_TYPE_UINT16_T
+AC_TYPE_UINT32_T
+AC_TYPE_UINT64_T
+AC_TYPE_UINT8_T
+AC_CHECK_TYPES([ptrdiff_t])
+
+# Checks for library functions.
+AC_FUNC_MALLOC
+AC_FUNC_MMAP
+AC_FUNC_REALLOC
+AC_CHECK_FUNCS([getcwd gettimeofday memmove memset munmap regcomp setlocale sqrt strdup strndup])
+
+AC_CONFIG_FILES([Makefile
+                 src/Makefile
+                 src/sparkey/Makefile])
+
+AM_CONDITIONAL([USE_DATE_STAT], [date -r . >/dev/null 2>&1])
+AM_CONDITIONAL([USE_STAT], [stat -f %Sm . >/dev/null 2>&1])
+
+AC_OUTPUT