lib/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 part of libgsasl.
   6  *
   7  * Libgsasl is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libgsasl is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with libgsasl; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  */
  22
  23 /* This file is based on src/global.c in libgcrypt */
  24
  25 #include "internal.h"
  26
  27 static const char*
  28 _gsasl_parse_version_number( const char *s, int *number )
  29 {
  30     int val = 0;
  31
  32     if( *s == '0' && isdigit(s[1]) )
  33         return NULL; /* leading zeros are not allowed */
  34     for ( ; isdigit(*s); s++ ) {
  35         val *= 10;
  36         val += *s - '0';
  37     }
  38     *number = val;
  39     return val < 0? NULL : s;
  40 }
  41
  42
  43 static const char *
  44 _gsasl_parse_version_string( const char *s, int *major, int *minor, int *micro )
  45 {
  46     s = _gsasl_parse_version_number( s, major );
  47     if( !s || *s != '.' )
  48         return NULL;
  49     s++;
  50     s = _gsasl_parse_version_number( s, minor );
  51     if( !s || *s != '.' )
  52         return NULL;
  53     s++;
  54     s = _gsasl_parse_version_number( s, micro );
  55     if( !s )
  56         return NULL;
  57     return s; /* patchlevel */
  58 }
  59
  60 /**
  61  * gsasl_check_version:
  62  * @req_version: version string to compare with, or NULL
  63  *
  64  * Check that the the version of the library is at minimum the one
  65  * given as a string in @var{req_version} and return the actual
  66  * version string of the library; return NULL if the condition is not
  67  * met.  If @code{NULL} is passed to this function no check is done
  68  * and only the version string is returned.  It is a pretty good idea
  69  * to run this function as soon as possible, because it may also
  70  * intializes some subsystems.  In a multithreaded environment if
  71  * should be called before any more threads are created.
  72  **/
  73 const char *
  74 gsasl_check_version (const char *req_version)
  75 {
  76     const char *ver = VERSION;
  77     int my_major, my_minor, my_micro;
  78     int rq_major, rq_minor, rq_micro;
  79     const char *my_plvl, *rq_plvl;
  80
  81     if ( !req_version )
  82         return ver;
  83
  84     my_plvl = _gsasl_parse_version_string( ver,
  85                                             &my_major, &my_minor, &my_micro );
  86     if ( !my_plvl )
  87         return NULL;  /* very strange our own version is bogus */
  88     rq_plvl = _gsasl_parse_version_string( req_version, &rq_major, &rq_minor,
  89                                                                 &rq_micro );
  90     if ( !rq_plvl )
  91         return NULL;  /* req version string is invalid */
  92
  93     if ( my_major > rq_major
  94         || (my_major == rq_major && my_minor > rq_minor)
  95         || (my_major == rq_major && my_minor == rq_minor
  96                                  && my_micro > rq_micro)
  97         || (my_major == rq_major && my_minor == rq_minor
  98                                  && my_micro == rq_micro
  99                                  && strcmp( my_plvl, rq_plvl ) >= 0) ) {
 100         return ver;
 101     }
 102     return NULL;
 103 }