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Diffstat (limited to '')
-rw-r--r-- | m4/strndup.m4 | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/m4/strndup.m4 b/m4/strndup.m4 new file mode 100644 index 0000000..a239d45 --- /dev/null +++ b/m4/strndup.m4 @@ -0,0 +1,58 @@ +# strndup.m4 serial 23 +dnl Copyright (C) 2002-2003, 2005-2022 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +AC_DEFUN([gl_FUNC_STRNDUP], +[ + dnl Persuade glibc <string.h> to declare strndup(). + AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS]) + + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_REQUIRE([gl_STRING_H_DEFAULTS]) + AC_CHECK_DECLS_ONCE([strndup]) + AC_CHECK_FUNCS_ONCE([strndup]) + if test $ac_cv_have_decl_strndup = no; then + HAVE_DECL_STRNDUP=0 + fi + + if test $ac_cv_func_strndup = yes; then + HAVE_STRNDUP=1 + # AIX 4.3.3, AIX 5.1 have a function that fails to add the terminating '\0'. + AC_CACHE_CHECK([for working strndup], [gl_cv_func_strndup_works], + [AC_RUN_IFELSE([ + AC_LANG_PROGRAM([[#include <string.h> + #include <stdlib.h>]], [[ +#if !HAVE_DECL_STRNDUP + extern + #ifdef __cplusplus + "C" + #endif + char *strndup (const char *, size_t); +#endif + int result; + char *s; + s = strndup ("some longer string", 15); + free (s); + s = strndup ("shorter string", 13); + result = s[13] != '\0'; + free (s); + return result;]])], + [gl_cv_func_strndup_works=yes], + [gl_cv_func_strndup_works=no], + [ +changequote(,)dnl + case $host_os in + aix | aix[3-6]*) gl_cv_func_strndup_works="guessing no";; + *) gl_cv_func_strndup_works="guessing yes";; + esac +changequote([,])dnl + ])]) + case $gl_cv_func_strndup_works in + *no) REPLACE_STRNDUP=1 ;; + esac + else + HAVE_STRNDUP=0 + fi +]) |