ldconfig: Move endswithn into a new header file

is_gdb_python_file is doing a similar test, so it can use this helper
function as well.

Signed-off-by: Adam Sampson <ats@offog.org>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

3 files changed, 36 insertions, 12 deletions

diff --git a/elf/endswith.h b/elf/endswith.h
new file mode 100644
index 0000000..c6430c4
--- /dev/null
+++ b/elf/endswith.h
@@ -0,0 +1,33 @@
+/* Copyright (C) 2023-2024 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published
+   by the Free Software Foundation; version 2 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <https://www.gnu.org/licenses/>.  */
+
+#ifndef _ENDSWITH_H
+#define _ENDSWITH_H
+
+#include <string.h>
+
+/* Return true if the N bytes at NAME end with with the characters in
+   the string SUFFIX.  (NAME[N + 1] does not have to be a null byte.)
+   Expected to be called with a string literal for SUFFIX.  */
+static inline bool
+endswithn (const char *name, size_t n, const char *suffix)
+{
+  return (n >= strlen (suffix)
+	  && memcmp (name + n - strlen (suffix), suffix,
+		     strlen (suffix)) == 0);
+}
+
+#endif /* _ENDSWITH_H */
diff --git a/elf/ldconfig.c b/elf/ldconfig.c
index b64c54b..0f3ef70 100644
--- a/elf/ldconfig.c
+++ b/elf/ldconfig.c
@@ -40,6 +40,7 @@
 #include <libgen.h>
 
 #include <ldconfig.h>
+#include <endswith.h>
 #include <dl-cache.h>
 #include <dl-hwcaps.h>
 #include <dl-is_dso.h>
@@ -661,17 +662,6 @@ struct dlib_entry
   struct dlib_entry *next;
 };
 
-/* Return true if the N bytes at NAME end with with the characters in
-   the string SUFFIX.  (NAME[N + 1] does not have to be a null byte.)
-   Expected to be called with a string literal for SUFFIX.  */
-static inline bool
-endswithn (const char *name, size_t n, const char *suffix)
-{
-  return (n >= strlen (suffix)
-	  && memcmp (name + n - strlen (suffix), suffix,
-		     strlen (suffix)) == 0);
-}
-
 /* Skip some temporary DSO files.  These files may be partially written
    and lead to ldconfig crashes when examined.  */
 static bool
diff --git a/elf/readlib.c b/elf/readlib.c
index 4d67c74..32e8b8e 100644
--- a/elf/readlib.c
+++ b/elf/readlib.c
@@ -33,6 +33,7 @@
 #include <gnu/lib-names.h>
 
 #include <ldconfig.h>
+#include <endswith.h>
 
 #define Elf32_CLASS ELFCLASS32
 #define Elf64_CLASS ELFCLASS64
@@ -48,7 +49,7 @@ static bool
 is_gdb_python_file (const char *name)
 {
   size_t len = strlen (name);
-  return len > 7 && strcmp (name + len - 7, "-gdb.py") == 0;
+  return endswithn (name, len, "-gdb.py");
 }
 
 /* Returns 0 if everything is ok, != 0 in case of error.  */