xapian-core/common/safeuuid.h

   1 /** @file safeuuid.h
   2  *  @brief #include <uuid/uuid.h>, with alternative implementation for windows.
   3  */
   4 /* Copyright (C) 2008 Lemur Consulting Ltd
   5  * Copyright (C) 2009,2010,2013 Olly Betts
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program 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
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  20  */
  21
  22 #ifndef XAPIAN_INCLUDED_SAFEUUID_H
  23 #define XAPIAN_INCLUDED_SAFEUUID_H
  24
  25 #if defined __CYGWIN__ || defined __WIN32__
  26 # include "common/win32_uuid.h"
  27 #elif defined HAVE_UUID_UUID_H
  28 # include <uuid/uuid.h>
  29
  30 // Some UUID libraries lack const qualifiers.  Solaris is a particular
  31 // example which survives today (2009).  The libuuid from e2fsprogs (now in
  32 // util-linux-ng) gained const qualifiers in 2001.  It's hard to cast uuid_t
  33 // suitably as it is a typedef for an array in at least some implementations,
  34 // but we probably can't safely assume that.  We don't need to pass const
  35 // uuid_t, but we do need to pass const char *, so fix that with a macro
  36 // wrapper for uuid_parse().
  37 # ifndef uuid_parse
  38 #  define uuid_parse(IN, UU) (uuid_parse)(const_cast<char*>(IN), (UU))
  39 # endif
  40
  41 # ifndef HAVE_UUID_UNPARSE_LOWER
  42 /* Older versions of libuuid (such as that on CentOS 4.7) don't have
  43  * uuid_unparse_lower(), only uuid_unparse().  NB uu parameter not const
  44  * as uuid_unparse may take a non-const uuid_t parameter. */
  45 inline void uuid_unparse_lower(uuid_t uu, char *out) {
  46     uuid_unparse(uu, out);
  47     /* Characters in out are either 0-9, a-z, '-', or A-Z.  A-Z is mapped to
  48      * a-z by bitwise or with 0x20, and the others already have this bit set.
  49      */
  50     for (size_t i = 0; i < 36; ++i) out[i] |= 0x20;
  51 }
  52 # endif
  53
  54 #else
  55
  56 // UUID API on FreeBSD, NetBSD and AIX.
  57
  58 # ifdef _AIX
  59 /* AIX uses a byte typedef in its <uuid.h> which collides with ours, so use a
  60  * macro to rename theirs out of the way.
  61  */
  62 #  define byte xapian_hack_aix_uuid_byte
  63 #  include <uuid.h>
  64 #  undef byte
  65 # else
  66 #  include <uuid.h>
  67 # endif
  68
  69 # include <cstdlib>
  70 # include <cstring>
  71 # include <exception>
  72
  73 typedef unsigned char uuid_t_[16];
  74
  75 inline void
  76 uuid_generate(uuid_t_ out) {
  77     uuid_t uuid;
  78     uint32_t status;
  79     uuid_create(&uuid, &status);
  80     if (status != uuid_s_ok) {
  81         // Can only be uuid_s_no_memory it seems.
  82         throw std::bad_alloc();
  83     }
  84     std::memcpy(out, &uuid, sizeof(uuid_t_));
  85 }
  86
  87 inline int
  88 uuid_parse(const char * in, uuid_t_ uu)
  89 {
  90     uuid_t uuid;
  91     uint32_t status;
  92 #ifdef _AIX
  93     // AIX takes unsigned char* not const char *.
  94     char * nonconst_in = const_cast<char*>(in);
  95     unsigned char * unsigned_in = reinterpret_cast<unsigned char *>(nonconst_in);
  96     uuid_from_string(unsigned_in, &uuid, &status);
  97 #else
  98     uuid_from_string(in, &uuid, &status);
  99 #endif
 100     if (status != uuid_s_ok)
 101         return -1;
 102     std::memcpy(uu, &uuid, sizeof(uuid_t_));
 103     return 0;
 104 }
 105
 106 inline void
 107 uuid_unparse_lower(const uuid_t_ uu, char * out)
 108 {
 109     uuid_t uuid;
 110     uint32_t status;
 111     std::memcpy(&uuid, uu, sizeof(uuid_t));
 112 #ifdef _AIX
 113     // AIX takes unsigned char* not char *.
 114     unsigned char * result;
 115 #else
 116     char * result;
 117 #endif
 118     uuid_to_string(&uuid, &result, &status);
 119     std::memcpy(out, result, 36);
 120     std::free(result);
 121     if (status != uuid_s_ok) {
 122         // Could be uuid_s_bad_version (FIXME) or uuid_s_no_memory it seems.
 123         throw std::bad_alloc();
 124     }
 125     /* Characters in out are either 0-9, a-z, '-', or A-Z.  A-Z is mapped to
 126      * a-z by bitwise or with 0x20, and the others already have this bit set.
 127      */
 128     for (size_t i = 0; i < 36; ++i) out[i] |= 0x20;
 129 }
 130
 131 inline void
 132 uuid_clear(uuid_t_ uu)
 133 {
 134     std::memset(uu, 0, sizeof(uuid_t_));
 135 }
 136
 137 inline int
 138 uuid_is_null(const uuid_t_ uu)
 139 {
 140     size_t i = 0;
 141     while (i < sizeof(uuid_t_)) {
 142         if (uu[i++])
 143             return 0;
 144     }
 145     return 1;
 146 }
 147
 148 // Hide incompatible uuid_t from <uuid.h>.
 149 # define uuid_t uuid_t_
 150
 151 #endif
 152
 153 #endif // XAPIAN_INCLUDED_SAFEUUID_H