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, 104 deletions

diff --git a/lib/gnulib.mk.in b/lib/gnulib.mk.in
index 78ecb544c6e..785bdc70c5c 100644
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@@ -157,7 +157,6 @@
 #  stddef \
 #  stdio \
 #  stpcpy \
-#  stpncpy \
 #  strnlen \
 #  strtoimax \
 #  symlink \
@@ -336,7 +335,6 @@ GL_COND_OBJ_SIGDESCR_NP_CONDITION = @GL_COND_OBJ_SIGDESCR_NP_CONDITION@
 GL_COND_OBJ_STDIO_READ_CONDITION = @GL_COND_OBJ_STDIO_READ_CONDITION@
 GL_COND_OBJ_STDIO_WRITE_CONDITION = @GL_COND_OBJ_STDIO_WRITE_CONDITION@
 GL_COND_OBJ_STPCPY_CONDITION = @GL_COND_OBJ_STPCPY_CONDITION@
-GL_COND_OBJ_STPNCPY_CONDITION = @GL_COND_OBJ_STPNCPY_CONDITION@
 GL_COND_OBJ_STRNLEN_CONDITION = @GL_COND_OBJ_STRNLEN_CONDITION@
 GL_COND_OBJ_STRTOIMAX_CONDITION = @GL_COND_OBJ_STRTOIMAX_CONDITION@
 GL_COND_OBJ_STRTOLL_CONDITION = @GL_COND_OBJ_STRTOLL_CONDITION@
@@ -3454,16 +3452,6 @@ endif
 endif
 ## end   gnulib module stpcpy
 
-## begin gnulib module stpncpy
-ifeq (,$(OMIT_GNULIB_MODULE_stpncpy))
-
-ifneq (,$(GL_COND_OBJ_STPNCPY_CONDITION))
-libgnu_a_SOURCES += stpncpy.c
-endif
-
-endif
-## end   gnulib module stpncpy
-
 ## begin gnulib module string
 ifeq (,$(OMIT_GNULIB_MODULE_string))
 
diff --git a/lib/stpncpy.c b/lib/stpncpy.c
deleted file mode 100644
index d1422a927df..00000000000
--- a/lib/stpncpy.c
+++ /dev/null
@@ -1,92 +0,0 @@
-/* Copyright (C) 1993, 1995-1997, 2002-2003, 2005-2007, 2009-2023 Free Software
- * Foundation, Inc.
-
-   NOTE: The canonical source of this file is maintained with the GNU C Library.
-   Bugs can be reported to bug-glibc@gnu.org.
-
-   This file is free software: you can redistribute it and/or modify
-   it under the terms of the GNU Lesser General Public License as
-   published by the Free Software Foundation; either version 2.1 of the
-   License, or (at your option) any later version.
-
-   This file is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-   GNU Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public License
-   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
-
-/* This is almost copied from strncpy.c, written by Torbjorn Granlund.  */
-
-#include <config.h>
-
-/* Specification.  */
-#include <string.h>
-
-#ifndef weak_alias
-# define __stpncpy stpncpy
-#endif
-
-/* Copy no more than N bytes of SRC to DST, returning a pointer past the
-   last non-NUL byte written into DST.  */
-char *
-(__stpncpy) (char *dest, const char *src, size_t n)
-{
-  char c;
-  char *s = dest;
-
-  if (n >= 4)
-    {
-      size_t n4 = n >> 2;
-
-      for (;;)
-        {
-          c = *src++;
-          *dest++ = c;
-          if (c == '\0')
-            break;
-          c = *src++;
-          *dest++ = c;
-          if (c == '\0')
-            break;
-          c = *src++;
-          *dest++ = c;
-          if (c == '\0')
-            break;
-          c = *src++;
-          *dest++ = c;
-          if (c == '\0')
-            break;
-          if (--n4 == 0)
-            goto last_chars;
-        }
-      n -= dest - s;
-      goto zero_fill;
-    }
-
- last_chars:
-  n &= 3;
-  if (n == 0)
-    return dest;
-
-  for (;;)
-    {
-      c = *src++;
-      --n;
-      *dest++ = c;
-      if (c == '\0')
-        break;
-      if (n == 0)
-        return dest;
-    }
-
- zero_fill:
-  while (n-- > 0)
-    dest[n] = '\0';
-
-  return dest - 1;
-}
-#ifdef weak_alias
-weak_alias (__stpncpy, stpncpy)
-#endif