xapian-core/common/win32_uuid.cc

   1 /** @file win32_uuid.cc
   2  * @brief Provide UUID functions compatible with libuuid from util-linux-ng.
   3  */
   4 /* Copyright (C) 2008 Lemur Consulting Ltd
   5  * Copyright (C) 2013,2015 Olly Betts
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (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 #include <config.h>
  23
  24 #include "win32_uuid.h"
  25
  26 #include "xapian/error.h"
  27
  28 #include <cstring>
  29
  30 #ifdef __WIN32__
  31 # include "safewinsock2.h" // For htonl() and htons().
  32 #else
  33 // Cygwin:
  34 # include <arpa/inet.h> // For htonl() and htons().
  35 #endif
  36
  37 using namespace std;
  38
  39 /// The size of a UUID in bytes.
  40 const size_t UUID_SIZE = 16;
  41
  42 /// The size of a UUID string in bytes (not including trailing '\0').
  43 const size_t UUID_STRING_SIZE = 36;
  44
  45 void
  46 uuid_generate(uuid_t uu)
  47 {
  48     UUID uuid;
  49     if (rare(UuidCreate(&uuid) != RPC_S_OK)) {
  50         // Throw a DatabaseCreateError, since we can't make a UUID.  The
  51         // windows API documentation is a bit unclear about the situations in
  52         // which this can happen, but if this behaviour causes a problem, an
  53         // alternative would be to create a UUID ourselves somehow in this
  54         // situation.
  55         throw Xapian::DatabaseCreateError("Cannot create UUID");
  56     }
  57     uuid.Data1 = htonl(uuid.Data1);
  58     uuid.Data2 = htons(uuid.Data2);
  59     uuid.Data3 = htons(uuid.Data3);
  60     memcpy(uu, &uuid, UUID_SIZE);
  61 }
  62
  63 int
  64 uuid_parse(const char * in, uuid_t uu)
  65 {
  66     UUID uuid;
  67     // UuidFromString() requires a non-const unsigned char * pointer, though it
  68     // doesn't modify the passed string.
  69     unsigned char * in_ = (unsigned char *)const_cast<char *>(in);
  70     if (UuidFromString(in_, &uuid) != RPC_S_OK)
  71         return -1;
  72     uuid.Data1 = htonl(uuid.Data1);
  73     uuid.Data2 = htons(uuid.Data2);
  74     uuid.Data3 = htons(uuid.Data3);
  75     memcpy(uu, &uuid, UUID_SIZE);
  76     return 0;
  77 }
  78
  79 void uuid_unparse_lower(const uuid_t uu, char * out)
  80 {
  81     UUID uuid;
  82     char *uuidstr;
  83     memcpy(&uuid, uu, UUID_SIZE);
  84     uuid.Data1 = htonl(uuid.Data1);
  85     uuid.Data2 = htons(uuid.Data2);
  86     uuid.Data3 = htons(uuid.Data3);
  87     if (rare(UuidToString(&uuid, (unsigned char **)(&uuidstr)) != RPC_S_OK)) {
  88         // The only documented (or really conceivable) error code is
  89         // RPC_S_OUT_OF_MEMORY.
  90         throw std::bad_alloc();
  91     }
  92     memcpy(out, strlwr(uuidstr), UUID_STRING_SIZE);
  93     out[UUID_STRING_SIZE] = '\0';
  94     RpcStringFree((unsigned char**)(&uuidstr));
  95 }
  96
  97 void uuid_clear(uuid_t uu)
  98 {
  99     memset(uu, 0, UUID_SIZE);
 100 }
 101
 102 int uuid_is_null(const uuid_t uu)
 103 {
 104     unsigned i = 0;
 105     while (i < UUID_SIZE) {
 106         if (uu[i++])
 107             return 0;
 108     }
 109     return 1;
 110 }