Re: check_version

[Simon Josefsson]

Paul Eggert <address@hidden> writes:

> Simon Josefsson <address@hidden> writes:
>
>>        /* Check version of libgcrypt. */
>>        if (!gcry_check_version (GCRYPT_VERSION))
>>          die ("version mismatch\n");
>
> Can't you use strverscmp for this?  E.g.:
>
>     if (strverscmp (GCRYPT_VERSION, VERSION) < 0)
>       die ("version mismatch\n");
>
> Even if strverscmp itself can't be used directly, it seems to me that
> its use would greatly simplify this package, and avoid the
> integer-overflow glitches Jim mentioned.

Good idea!  How about this?

2005-06-25  Simon Josefsson  <address@hidden>

        * modules/check_version: New file.

2005-06-25  Simon Josefsson  <address@hidden>

        * check_version.h, check_version.c: New file.

Index: lib/check_version.c
===================================================================
RCS file: lib/check_version.c
diff -N lib/check_version.c
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ lib/check_version.c 27 Jun 2005 22:23:39 -0000
@@ -0,0 +1,47 @@
+/* check_version.h --- Check version string compatibility.
+   Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free
+   Software Foundation, Inc.
+
+   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; either version 2, 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, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+/* Written by Simon Josefsson.  This interface is influenced by
+   gcry_check_version from Werner Koch's Libgcrypt.  Paul Eggert
+   suggested the use of strverscmp to simplify implementation. */
+
+#if HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <stddef.h>
+#include <strverscmp.h>
+
+/* Get specification. */
+#include "check_version.h"
+
+/* Check that the the version of the library (i.e., the CPP symbol
+ * VERSION) is at minimum the requested one in REQ_VERSION (typically
+ * found in a header file) and return the version string.  Return NULL
+ * if the condition is not satisfied.  If a NULL is passed to this
+ * function, no check is done, but the version string is simply
+ * returned.
+ */
+const char *
+check_version (const char *req_version)
+{
+  if (!req_version || strverscmp (req_version, VERSION) < 0)
+    return VERSION;
+
+  return NULL;
+}
Index: lib/check_version.h
===================================================================
RCS file: lib/check_version.h
diff -N lib/check_version.h
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ lib/check_version.h 27 Jun 2005 22:23:39 -0000
@@ -0,0 +1,26 @@
+/* check_version.h --- Check version string compatibility.
+   Copyright (C) 2005 Free Software Foundation, Inc.
+
+   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; either version 2, 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, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+/* Written by Simon Josefsson. */
+
+#ifndef CHECK_VERSION_H
+# define CHECK_VERSION_H
+
+extern const char *
+check_version (const char *req_version);
+
+#endif /* CHECK_VERSION_H */
Index: modules/check_version
===================================================================
RCS file: modules/check_version
diff -N modules/check_version
--- /dev/null   1 Jan 1970 00:00:00 -0000
+++ modules/check_version       27 Jun 2005 22:23:39 -0000
@@ -0,0 +1,23 @@
+Description:
+Check version string compatibility.
+
+Files:
+lib/check_version.h
+lib/check_version.c
+
+Depends-on:
+strverscmp
+
+configure.ac:
+
+Makefile.am:
+lib_SOURCES += check_version.h check_version.c
+
+Include:
+"check_version.h"
+
+License:
+LGPL
+
+Maintainer:
+Simon Josefsson