FS-8736 #resolve [Missing MEMMOVE macro in spandsp autoconf]

libs/spandsp/configure.ac

@@ -37,6 +37,7 @@ m4_include(m4/ax_c99_features.m4)
 m4_include(m4/ax_check_export_capability.m4)
 m4_include(m4/ax_check_arm_neon.m4)
 m4_include(m4/ax_func_aligned_alloc.m4)
+m4_include(m4/memmove.m4)
 
 AC_CONFIG_SRCDIR([src/tone_generate.c])
 AC_CONFIG_AUX_DIR([config])
@@ -152,6 +153,7 @@ AC_FUNC_ERROR_AT_LINE
 AC_FUNC_VPRINTF
 AC_FUNC_MEMCMP
 AC_FUNC_MEMMOVE
+
 if test "${ax_cv_c_compiler_vendor}" = "gnu"
   then
     AC_FUNC_REALLOC

libs/spandsp/m4/memmove.m4

+AC_DEFUN([AC_FUNC_MEMMOVE],
+[AC_CHECK_FUNCS(memmove)
+AC_MSG_CHECKING(for working memmove)
+AC_CACHE_VAL(ac_cv_have_working_memmove,
+[AC_TRY_RUN(
+[#include <stdio.h>
+
+int main(void)
+{
+    char buf[10];
+    strcpy (buf, "01234567");
+    memmove (buf, buf + 2, 3);
+    if (strcmp (buf, "23434567"))
+        exit (1);
+    strcpy (buf, "01234567");
+    memmove (buf + 2, buf, 3);
+    if (strcmp (buf, "01012567"))
+        exit (1);
+    exit (0);
+}], ac_cv_have_working_memmove=yes, ac_cv_have_working_memmove=no, ac_cv_have_working_memmove=cross)])
+AC_MSG_RESULT([$ac_cv_have_working_memmove])
+if test x$ac_cv_have_working_memmove != "xyes"; then
+  AC_LIBOBJ(memmove)
+  AC_MSG_WARN([Replacing missing/broken memmove.])
+  AC_DEFINE(PREFER_PORTABLE_MEMMOVE, 1, "enable replacement memmove if system memmove is broken or missing")
+fi])
+