apt-pkg/contrib/error.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 /* ######################################################################
   4
   5    Global Error Class - Global error mechanism
   6
   7    We use a simple STL vector to store each error record. A PendingFlag
   8    is kept which indicates when the vector contains a Sever error.
   9
  10    This source is placed in the Public Domain, do with it what you will
  11    It was originally written by Jason Gunthorpe.
  12
  13    ##################################################################### */
  14                                                                         /*}}}*/
  15 // Include Files                                                        /*{{{*/
  16 #include <config.h>
  17
  18 #include <apt-pkg/error.h>
  19
  20 #include <iostream>
  21 #include <errno.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <unistd.h>
  25
  26 #include <string>
  27 #include <cstring>
  28
  29                                                                         /*}}}*/
  30
  31 // Global Error Object                                                  /*{{{*/
  32 /* If the implementation supports posix threads then the accessor function
  33    is compiled to be thread safe otherwise a non-safe version is used. A
  34    Per-Thread error object is maintained in much the same manner as libc
  35    manages errno */
  36 #if defined(_POSIX_THREADS) && defined(HAVE_PTHREAD)
  37         #include <pthread.h>
  38
  39         static pthread_key_t ErrorKey;
  40         static void ErrorDestroy(void *Obj) {delete (GlobalError *)Obj;};
  41         static void KeyAlloc() {pthread_key_create(&ErrorKey,ErrorDestroy);};
  42
  43         GlobalError *_GetErrorObj() {
  44                 static pthread_once_t Once = PTHREAD_ONCE_INIT;
  45                 pthread_once(&Once,KeyAlloc);
  46
  47                 void *Res = pthread_getspecific(ErrorKey);
  48                 if (Res == 0)
  49                         pthread_setspecific(ErrorKey,Res = new GlobalError);
  50                 return (GlobalError *)Res;
  51         }
  52 #else
  53         GlobalError *_GetErrorObj() {
  54                 static GlobalError *Obj = new GlobalError;
  55                 return Obj;
  56         }
  57 #endif
  58                                                                         /*}}}*/
  59 // GlobalError::GlobalError - Constructor                               /*{{{*/
  60 GlobalError::GlobalError() : PendingFlag(false) {}
  61                                                                         /*}}}*/
  62 // GlobalError::FatalE, Errno, WarningE, NoticeE and DebugE - Add to the list/*{{{*/
  63 #define GEMessage(NAME, TYPE) \
  64 bool GlobalError::NAME (const char *Function, const char *Description,...) { \
  65         va_list args; \
  66         size_t msgSize = 400; \
  67         int const errsv = errno; \
  68         while (true) { \
  69                 va_start(args,Description); \
  70                 if (InsertErrno(TYPE, Function, Description, args, errsv, msgSize) == false) \
  71                         break; \
  72                 va_end(args); \
  73         } \
  74         return false; \
  75 }
  76 GEMessage(FatalE, FATAL)
  77 GEMessage(Errno, ERROR)
  78 GEMessage(WarningE, WARNING)
  79 GEMessage(NoticeE, NOTICE)
  80 GEMessage(DebugE, DEBUG)
  81 #undef GEMessage
  82                                                                         /*}}}*/
  83 // GlobalError::InsertErrno - Get part of the errortype string from errno/*{{{*/
  84 bool GlobalError::InsertErrno(MsgType const &type, const char *Function,
  85                                 const char *Description,...) {
  86         va_list args;
  87         size_t msgSize = 400;
  88         int const errsv = errno;
  89         while (true) {
  90                 va_start(args,Description);
  91                 if (InsertErrno(type, Function, Description, args, errsv, msgSize) == false)
  92                         break;
  93                 va_end(args);
  94         }
  95         return false;
  96 }
  97                                                                         /*}}}*/
  98 // GlobalError::InsertErrno - formats an error message with the errno   /*{{{*/
  99 bool GlobalError::InsertErrno(MsgType type, const char* Function,
 100                               const char* Description, va_list &args,
 101                               int const errsv, size_t &msgSize) {
 102         char* S = (char*) malloc(msgSize);
 103         int const n = snprintf(S, msgSize, "%s - %s (%i: %s)", Description,
 104                                Function, errsv, strerror(errsv));
 105         if (n > -1 && ((unsigned int) n) < msgSize);
 106         else {
 107                 if (n > -1)
 108                         msgSize = n + 1;
 109                 else
 110                         msgSize *= 2;
 111                 free(S);
 112                 return true;
 113         }
 114
 115         bool const geins = Insert(type, S, args, msgSize);
 116         free(S);
 117         return geins;
 118 }
 119                                                                         /*}}}*/
 120 // GlobalError::Fatal, Error, Warning, Notice and Debug - Add to the list/*{{{*/
 121 #define GEMessage(NAME, TYPE) \
 122 bool GlobalError::NAME (const char *Description,...) { \
 123         va_list args; \
 124         size_t msgSize = 400; \
 125         while (true) { \
 126                 va_start(args,Description); \
 127                 if (Insert(TYPE, Description, args, msgSize) == false) \
 128                         break; \
 129                 va_end(args); \
 130         } \
 131         return false; \
 132 }
 133 GEMessage(Fatal, FATAL)
 134 GEMessage(Error, ERROR)
 135 GEMessage(Warning, WARNING)
 136 GEMessage(Notice, NOTICE)
 137 GEMessage(Debug, DEBUG)
 138 #undef GEMessage
 139                                                                         /*}}}*/
 140 // GlobalError::Insert - Add a errotype message to the list             /*{{{*/
 141 bool GlobalError::Insert(MsgType const &type, const char *Description,...)
 142 {
 143         va_list args;
 144         size_t msgSize = 400;
 145         while (true) {
 146                 va_start(args,Description);
 147                 if (Insert(type, Description, args, msgSize) == false)
 148                         break;
 149                 va_end(args);
 150         }
 151         return false;
 152 }
 153                                                                         /*}}}*/
 154 // GlobalError::Insert - Insert a new item at the end                   /*{{{*/
 155 bool GlobalError::Insert(MsgType type, const char* Description,
 156                          va_list &args, size_t &msgSize) {
 157         char* S = (char*) malloc(msgSize);
 158         int const n = vsnprintf(S, msgSize, Description, args);
 159         if (n > -1 && ((unsigned int) n) < msgSize);
 160         else {
 161                 if (n > -1)
 162                         msgSize = n + 1;
 163                 else
 164                         msgSize *= 2;
 165                 free(S);
 166                 return true;
 167         }
 168
 169         Item const m(S, type);
 170         Messages.push_back(m);
 171
 172         if (type == ERROR || type == FATAL)
 173                 PendingFlag = true;
 174
 175         if (type == FATAL || type == DEBUG)
 176                 std::clog << m << std::endl;
 177
 178         free(S);
 179         return false;
 180 }
 181                                                                         /*}}}*/
 182 // GlobalError::PopMessage - Pulls a single message out                 /*{{{*/
 183 bool GlobalError::PopMessage(std::string &Text) {
 184         if (Messages.empty() == true)
 185                 return false;
 186
 187         Item const msg = Messages.front();
 188         Messages.pop_front();
 189
 190         bool const Ret = (msg.Type == ERROR || msg.Type == FATAL);
 191         Text = msg.Text;
 192         if (PendingFlag == false || Ret == false)
 193                 return Ret;
 194
 195         // check if another error message is pending
 196         for (std::list<Item>::const_iterator m = Messages.begin();
 197              m != Messages.end(); ++m)
 198                 if (m->Type == ERROR || m->Type == FATAL)
 199                         return Ret;
 200
 201         PendingFlag = false;
 202         return Ret;
 203 }
 204                                                                         /*}}}*/
 205 // GlobalError::DumpErrors - Dump all of the errors/warns to cerr       /*{{{*/
 206 void GlobalError::DumpErrors(std::ostream &out, MsgType const &threshold,
 207                              bool const &mergeStack) {
 208         if (mergeStack == true)
 209                 for (std::list<MsgStack>::const_reverse_iterator s = Stacks.rbegin();
 210                      s != Stacks.rend(); ++s)
 211                         Messages.insert(Messages.begin(), s->Messages.begin(), s->Messages.end());
 212
 213         for (std::list<Item>::const_iterator m = Messages.begin();
 214              m != Messages.end(); ++m)
 215                 if (m->Type >= threshold)
 216                         out << (*m) << std::endl;
 217         Discard();
 218 }
 219                                                                         /*}}}*/
 220 // GlobalError::Discard - Discard                                       /*{{{*/
 221 void GlobalError::Discard() {
 222         Messages.clear();
 223         PendingFlag = false;
 224 };
 225                                                                         /*}}}*/
 226 // GlobalError::empty - does our error list include anything?           /*{{{*/
 227 bool GlobalError::empty(MsgType const &trashhold) const {
 228         if (PendingFlag == true)
 229                 return false;
 230
 231         if (Messages.empty() == true)
 232                 return true;
 233
 234         for (std::list<Item>::const_iterator m = Messages.begin();
 235              m != Messages.end(); ++m)
 236                 if (m->Type >= trashhold)
 237                         return false;
 238
 239         return true;
 240 }
 241                                                                         /*}}}*/
 242 // GlobalError::PushToStack                                             /*{{{*/
 243 void GlobalError::PushToStack() {
 244         MsgStack pack(Messages, PendingFlag);
 245         Stacks.push_back(pack);
 246         Discard();
 247 }
 248                                                                         /*}}}*/
 249 // GlobalError::RevertToStack                                           /*{{{*/
 250 void GlobalError::RevertToStack() {
 251         Discard();
 252         MsgStack pack = Stacks.back();
 253         Messages = pack.Messages;
 254         PendingFlag = pack.PendingFlag;
 255         Stacks.pop_back();
 256 }
 257                                                                         /*}}}*/
 258 // GlobalError::MergeWithStack                                          /*{{{*/
 259 void GlobalError::MergeWithStack() {
 260         MsgStack pack = Stacks.back();
 261         Messages.insert(Messages.begin(), pack.Messages.begin(), pack.Messages.end());
 262         PendingFlag = PendingFlag || pack.PendingFlag;
 263         Stacks.pop_back();
 264 }
 265                                                                         /*}}}*/