Avoid stpncpy

It’s not worth the porting hassle, and as the glibc manual says,
“this function is generally a poor choice for processing strings”.
* admin/merge-gnulib (GNULIB_MODULES): Remove stpncpy.
* exec/configure.ac: Do not check for stpncpy.
* exec/exec.c (rpl_stpncpy, stpncpy): Remove this replacement.
(exec_0): Properly clear buffer1.  Use memcpy instead of
stpncpy to add the trailing name.  This code is clearly
still suboptimal but efficiency is not that important here
and I tried to minimize the change.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.

2 files changed, 0 insertions, 118 deletions

diff --git a/m4/gnulib-comp.m4 b/m4/gnulib-comp.m4
index 72adcf90d5e..3382e9bc241 100644
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@@ -181,7 +181,6 @@ AC_DEFUN([gl_EARLY],
   gl_STDIO_H_EARLY
   # Code from module stdlib:
   # Code from module stpcpy:
-  # Code from module stpncpy:
   # Code from module string:
   # Code from module strnlen:
   # Code from module strtoimax:
@@ -567,13 +566,6 @@ AC_DEFUN([gl_INIT],
     gl_PREREQ_STPCPY
   ])
   gl_STRING_MODULE_INDICATOR([stpcpy])
-  gl_FUNC_STPNCPY
-  gl_CONDITIONAL([GL_COND_OBJ_STPNCPY],
-                 [test $HAVE_STPNCPY = 0 || test $REPLACE_STPNCPY = 1])
-  AM_COND_IF([GL_COND_OBJ_STPNCPY], [
-    gl_PREREQ_STPNCPY
-  ])
-  gl_STRING_MODULE_INDICATOR([stpncpy])
   gl_STRING_H
   gl_STRING_H_REQUIRE_DEFAULTS
   AC_PROG_MKDIR_P
@@ -1422,7 +1414,6 @@ AC_DEFUN([gl_FILE_LIST], [
   lib/stdio.in.h
   lib/stdlib.in.h
   lib/stpcpy.c
-  lib/stpncpy.c
   lib/str-two-way.h
   lib/strftime.h
   lib/string.in.h
@@ -1569,7 +1560,6 @@ AC_DEFUN([gl_FILE_LIST], [
   m4/stdio_h.m4
   m4/stdlib_h.m4
   m4/stpcpy.m4
-  m4/stpncpy.m4
   m4/string_h.m4
   m4/strnlen.m4
   m4/strtoimax.m4
diff --git a/m4/stpncpy.m4 b/m4/stpncpy.m4
deleted file mode 100644
index 073607004be..00000000000
--- a/m4/stpncpy.m4
+++ /dev/null
@@ -1,108 +0,0 @@
-# stpncpy.m4 serial 22
-dnl Copyright (C) 2002-2003, 2005-2007, 2009-2023 Free Software Foundation,
-dnl 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_STPNCPY],
-[
-  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
-
-  dnl Persuade glibc <string.h> to declare stpncpy().
-  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
-
-  dnl The stpncpy() declaration in lib/string.in.h uses 'restrict'.
-  AC_REQUIRE([AC_C_RESTRICT])
-
-  AC_REQUIRE([gl_STRING_H_DEFAULTS])
-
-  dnl Both glibc and AIX (4.3.3, 5.1) have an stpncpy() function
-  dnl declared in <string.h>. Its side effects are the same as those
-  dnl of strncpy():
-  dnl      stpncpy (dest, src, n)
-  dnl overwrites dest[0..n-1], min(strlen(src),n) bytes coming from src,
-  dnl and the remaining bytes being NULs.  However, the return value is
-  dnl   in glibc:   dest + min(strlen(src),n)
-  dnl   in AIX:     dest + max(0,n-1)
-  dnl Only the glibc return value is useful in practice.
-
-  AC_CHECK_DECLS_ONCE([stpncpy])
-  gl_CHECK_FUNCS_ANDROID([stpncpy], [[#include <string.h>]])
-  if test $ac_cv_func_stpncpy = yes; then
-    AC_CACHE_CHECK([for working stpncpy], [gl_cv_func_stpncpy], [
-      AC_RUN_IFELSE(
-        [AC_LANG_SOURCE([[
-#include <stdlib.h>
-#include <string.h> /* for strcpy */
-/* The stpncpy prototype is missing in <string.h> on AIX 4.  */
-#if !HAVE_DECL_STPNCPY
-extern
-# ifdef __cplusplus
-"C"
-# endif
-char *stpncpy (char *dest, const char *src, size_t n);
-#endif
-int main ()
-{
-  int result = 0;
-  const char *src = "Hello";
-  char dest[10];
-  /* AIX 4.3.3 and AIX 5.1 stpncpy() returns dest+1 here.  */
-  {
-    strcpy (dest, "\377\377\377\377\377\377");
-    if (stpncpy (dest, src, 2) != dest + 2)
-      result |= 1;
-  }
-  /* AIX 4.3.3 and AIX 5.1 stpncpy() returns dest+4 here.  */
-  {
-    strcpy (dest, "\377\377\377\377\377\377");
-    if (stpncpy (dest, src, 5) != dest + 5)
-      result |= 2;
-  }
-  /* AIX 4.3.3 and AIX 5.1 stpncpy() returns dest+6 here.  */
-  {
-    strcpy (dest, "\377\377\377\377\377\377");
-    if (stpncpy (dest, src, 7) != dest + 5)
-      result |= 4;
-  }
-  return result;
-}
-]])],
-        [gl_cv_func_stpncpy=yes],
-        [gl_cv_func_stpncpy=no],
-        [dnl Guess yes on glibc systems and musl systems.
-         AC_EGREP_CPP([Thanks for using GNU], [
-#include <features.h>
-#ifdef __GNU_LIBRARY__
-  Thanks for using GNU
-#endif
-],         [gl_cv_func_stpncpy="guessing yes"],
-           [case "$host_os" in
-              *-musl* | midipix*) gl_cv_func_stpncpy="guessing yes" ;;
-              *)                  gl_cv_func_stpncpy="$gl_cross_guess_normal" ;;
-            esac
-           ])
-        ])
-    ])
-    case "$gl_cv_func_stpncpy" in
-      *yes)
-        AC_DEFINE([HAVE_STPNCPY], [1],
-          [Define if you have the stpncpy() function and it works.])
-        ;;
-      *)
-        REPLACE_STPNCPY=1
-        ;;
-    esac
-  else
-    HAVE_STPNCPY=0
-    case "$gl_cv_onwards_func_stpncpy" in
-      future*) REPLACE_STPNCPY=1 ;;
-    esac
-  fi
-])
-
-# Prerequisites of lib/stpncpy.c.
-AC_DEFUN([gl_PREREQ_STPNCPY], [
-  :
-])