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