[PATCH 2/4] style: make conversion of version string to int public

* src/parse-gram.y (str_to_version): Rename as/move to...
* src/strversion.h, src/strversion.c (strversion_to_int): these new
files.
---
 src/local.mk     |  2 ++
 src/parse-gram.y | 50 ++----------------------------------
 src/strversion.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++
 src/strversion.h | 28 ++++++++++++++++++++
 4 files changed, 99 insertions(+), 48 deletions(-)
 create mode 100644 src/strversion.c
 create mode 100644 src/strversion.h

diff --git a/src/local.mk b/src/local.mk
index 32d09d10..08ff62be 100644
--- a/src/local.mk
+++ b/src/local.mk
@@ -103,6 +103,8 @@ src_bison_SOURCES =                             \
   src/state.h                                   \
   src/state-item.c                              \
   src/state-item.h                              \
+  src/strversion.c                              \
+  src/strversion.h                              \
   src/symlist.c                                 \
   src/symlist.h                                 \
   src/symtab.c                                  \
diff --git a/src/parse-gram.y b/src/parse-gram.y
index dc776130..7c146ea3 100644
--- a/src/parse-gram.y
+++ b/src/parse-gram.y
@@ -42,8 +42,6 @@
   #include "system.h"
 
   #include <c-ctype.h>
-  #include <errno.h>
-  #include <intprops.h>
   #include <quotearg.h>
   #include <vasnprintf.h>
   #include <xmemdup0.h>
@@ -57,6 +55,7 @@
   #include "reader.h"
   #include "scan-code.h"
   #include "scan-gram.h"
+  #include "strversion.h"
 
   /* Pretend to be at least that version, to check features published
      in that version while developping it.  */
@@ -1043,56 +1042,11 @@ handle_pure_parser (location const *loc, char const *directive)
 }
 
 
-/* Convert VERSION into an int (MAJOR * 10000 + MINOR * 100 + MICRO).
-   E.g., "3.7.4" => 30704, "3.8" => 30800.
-   Return -1 on errors. */
-static int
-str_to_version (char const *version)
-{
-  IGNORE_TYPE_LIMITS_BEGIN
-  int res = 0;
-  errno = 0;
-  char *cp = NULL;
-
-  {
-    long major = strtol (version, &cp, 10);
-    if (errno || cp == version || *cp != '.' || major < 0
-        || INT_MULTIPLY_WRAPV (major, 10000, &res))
-      return -1;
-  }
-
-  {
-    ++cp;
-    char *prev = cp;
-    long minor = strtol (cp, &cp, 10);
-    if (errno || cp == prev || (*cp != '\0' && *cp != '.')
-        || ! (0 <= minor && minor < 100)
-        || INT_MULTIPLY_WRAPV (minor, 100, &minor)
-        || INT_ADD_WRAPV (minor, res, &res))
-      return -1;
-  }
-
-  if (*cp == '.')
-    {
-      ++cp;
-      char *prev = cp;
-      long micro = strtol (cp, &cp, 10);
-      if (errno || cp == prev || (*cp != '\0' && *cp != '.')
-          || ! (0 <= micro && micro < 100)
-          || INT_ADD_WRAPV (micro, res, &res))
-        return -1;
-    }
-
-  IGNORE_TYPE_LIMITS_END
-  return res;
-}
-
-
 static void
 handle_require (location const *loc, char const *version_quoted)
 {
   char *version = unquote (version_quoted);
-  required_version = str_to_version (version);
+  required_version = strversion_to_int (version);
   if (required_version == -1)
     {
       complain (loc, complaint, _("invalid version requirement: %s"),
diff --git a/src/strversion.c b/src/strversion.c
new file mode 100644
index 00000000..27c71d34
--- /dev/null
+++ b/src/strversion.c
@@ -0,0 +1,67 @@
+/* Convert version string to int.
+
+   Copyright (C) 2020 Free Software Foundation, Inc.
+
+   This file is part of Bison, the GNU Compiler Compiler.
+
+   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 3 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 <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+#include "system.h"
+
+#include "strversion.h"
+
+#include <errno.h>
+#include <intprops.h>
+
+int
+strversion_to_int (char const *version)
+{
+  IGNORE_TYPE_LIMITS_BEGIN
+  int res = 0;
+  errno = 0;
+  char *cp = NULL;
+
+  {
+    long major = strtol (version, &cp, 10);
+    if (errno || cp == version || *cp != '.' || major < 0
+        || INT_MULTIPLY_WRAPV (major, 10000, &res))
+      return -1;
+  }
+
+  {
+    ++cp;
+    char *prev = cp;
+    long minor = strtol (cp, &cp, 10);
+    if (errno || cp == prev || (*cp != '\0' && *cp != '.')
+        || ! (0 <= minor && minor < 100)
+        || INT_MULTIPLY_WRAPV (minor, 100, &minor)
+        || INT_ADD_WRAPV (minor, res, &res))
+      return -1;
+  }
+
+  if (*cp == '.')
+    {
+      ++cp;
+      char *prev = cp;
+      long micro = strtol (cp, &cp, 10);
+      if (errno || cp == prev || (*cp != '\0' && *cp != '.')
+          || ! (0 <= micro && micro < 100)
+          || INT_ADD_WRAPV (micro, res, &res))
+        return -1;
+    }
+
+  IGNORE_TYPE_LIMITS_END
+  return res;
+}
diff --git a/src/strversion.h b/src/strversion.h
new file mode 100644
index 00000000..6d8d6235
--- /dev/null
+++ b/src/strversion.h
@@ -0,0 +1,28 @@
+/* Convert version string to int.
+
+   Copyright (C) 2020 Free Software Foundation, Inc.
+
+   This file is part of Bison, the GNU Compiler Compiler.
+
+   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 3 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 <http://www.gnu.org/licenses/>.  */
+
+#ifndef STRVERSION_H_
+# define STRVERSION_H_
+
+/* Convert VERSION into an int (MAJOR * 10000 + MINOR * 100 + MICRO).
+   E.g., "3.7.4" => 30704, "3.8" => 30800.
+   Return -1 on errors. */
+int strversion_to_int (char const *version);
+
+#endif
-- 
2.29.2