version.c

   1 /* version.c    version handling
   2  * Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
   3  * Copyright (C) 2002  Simon Josefsson
   4  *
   5  * This file is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This file is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this file; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  */
  20
  21 /* This file is based on src/global.c from Werner Koch's libgcrypt */
  22
  23 #include "internal.h"
  24
  25 static const char *
  26 parse_version_number (const char *s, int *number)
  27 {
  28   int val = 0;
  29
  30   if (*s == '0' && isdigit (s[1]))
  31     return NULL;                /* leading zeros are not allowed */
  32   for (; isdigit (*s); s++)
  33     {
  34       val *= 10;
  35       val += *s - '0';
  36     }
  37   *number = val;
  38   return val < 0 ? NULL : s;
  39 }
  40
  41
  42 static const char *
  43 parse_version_string (const char *s, int *major, int *minor, int *micro)
  44 {
  45   s = parse_version_number (s, major);
  46   if (!s || *s != '.')
  47     return NULL;
  48   s++;
  49   s = parse_version_number (s, minor);
  50   if (!s || *s != '.')
  51     return NULL;
  52   s++;
  53   s = parse_version_number (s, micro);
  54   if (!s)
  55     return NULL;
  56   return s;                     /* patchlevel */
  57 }
  58
  59 /****************
  60  * Check that the the version of the library is at minimum the requested one
  61  * and return the version string; return NULL if the condition is not
  62  * satisfied.  If a NULL is passed to this function, no check is done,
  63  * but the version string is simply returned.
  64  */
  65 const char *
  66 stringprep_check_version (const char *req_version)
  67 {
  68   const char *ver = VERSION;
  69   int my_major, my_minor, my_micro;
  70   int rq_major, rq_minor, rq_micro;
  71   const char *my_plvl, *rq_plvl;
  72
  73   if (!req_version)
  74     return ver;
  75
  76   my_plvl = parse_version_string (ver, &my_major, &my_minor, &my_micro);
  77   if (!my_plvl)
  78     return NULL;                /* very strange our own version is bogus */
  79   rq_plvl = parse_version_string (req_version, &rq_major, &rq_minor,
  80                                   &rq_micro);
  81   if (!rq_plvl)
  82     return NULL;                /* req version string is invalid */
  83
  84   if (my_major > rq_major
  85       || (my_major == rq_major && my_minor > rq_minor)
  86       || (my_major == rq_major && my_minor == rq_minor
  87           && my_micro > rq_micro)
  88       || (my_major == rq_major && my_minor == rq_minor
  89           && my_micro == rq_micro && strcmp (my_plvl, rq_plvl) >= 0))
  90     {
  91       return ver;
  92     }
  93   return NULL;
  94 }