lib/version.c

   1 /* version.c    Version handling.
   2  * Copyright (C) 2002, 2003  Simon Josefsson
   3  * Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
   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 #if HAVE_CONFIG_H
  24 # include "config.h"
  25 #endif
  26
  27 #include <ctype.h>
  28 #include <string.h>
  29
  30 #include "stringprep.h"
  31
  32 static const char *
  33 parse_version_number (const char *s, int *number)
  34 {
  35   int val = 0;
  36
  37   if (*s == '0' && isdigit (s[1]))
  38     return NULL;                /* leading zeros are not allowed */
  39   for (; isdigit (*s); s++)
  40     {
  41       val *= 10;
  42       val += *s - '0';
  43     }
  44   *number = val;
  45   return val < 0 ? NULL : s;
  46 }
  47
  48
  49 static const char *
  50 parse_version_string (const char *s, int *major, int *minor, int *micro)
  51 {
  52   s = parse_version_number (s, major);
  53   if (!s || *s != '.')
  54     return NULL;
  55   s++;
  56   s = parse_version_number (s, minor);
  57   if (!s || *s != '.')
  58     return NULL;
  59   s++;
  60   s = parse_version_number (s, micro);
  61   if (!s)
  62     return NULL;
  63   return s;                     /* patchlevel */
  64 }
  65
  66 /**
  67  * stringprep_check_version
  68  * @req_version: Required version number, or NULL.
  69  *
  70  * Check that the the version of the library is at minimum the requested one
  71  * and return the version string; return NULL if the condition is not
  72  * satisfied.  If a NULL is passed to this function, no check is done,
  73  * but the version string is simply returned.
  74  *
  75  * See %STRINGPREP_VERSION for a suitable @req_version string.
  76  *
  77  * Return value: Version string of run-time library, or NULL if the
  78  * run-time library does not meet the required version number.
  79  */
  80 const char *
  81 stringprep_check_version (const char *req_version)
  82 {
  83   const char *ver = VERSION;
  84   int my_major, my_minor, my_micro;
  85   int rq_major, rq_minor, rq_micro;
  86   const char *my_plvl, *rq_plvl;
  87
  88   if (!req_version)
  89     return ver;
  90
  91   my_plvl = parse_version_string (ver, &my_major, &my_minor, &my_micro);
  92   if (!my_plvl)
  93     return NULL;                /* very strange our own version is bogus */
  94   rq_plvl = parse_version_string (req_version, &rq_major, &rq_minor,
  95                                   &rq_micro);
  96   if (!rq_plvl)
  97     return NULL;                /* req version string is invalid */
  98
  99   if (my_major > rq_major
 100       || (my_major == rq_major && my_minor > rq_minor)
 101       || (my_major == rq_major && my_minor == rq_minor
 102           && my_micro > rq_micro)
 103       || (my_major == rq_major && my_minor == rq_minor
 104           && my_micro == rq_micro && strcmp (my_plvl, rq_plvl) >= 0))
 105     {
 106       return ver;
 107     }
 108   return NULL;
 109 }