gold/readsyms.h

   1 // readsyms.h -- read input file symbols for gold   -*- C++ -*-
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
   4 // Written by Ian Lance Taylor <iant@google.com>.
   5
   6 // This file is part of gold.
   7
   8 // This program is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3 of the License, or
  11 // (at your option) any later version.
  12
  13 // This program is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this program; if not, write to the Free Software
  20 // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  21 // MA 02110-1301, USA.
  22
  23 #ifndef GOLD_READSYMS_H
  24 #define GOLD_READSYMS_H
  25
  26 #include <vector>
  27
  28 #include "workqueue.h"
  29 #include "object.h"
  30
  31 namespace gold
  32 {
  33
  34 class Input_objects;
  35 class Symbol_table;
  36 class Input_group;
  37 class Archive;
  38 class Finish_group;
  39
  40 // This Task is responsible for reading the symbols from an input
  41 // file.  This also includes reading the relocations so that we can
  42 // check for any that require a PLT and/or a GOT.  After the data has
  43 // been read, this queues up another task to actually add the symbols
  44 // to the symbol table.  The tasks are separated because the file
  45 // reading can occur in parallel but adding the symbols must be done
  46 // in the order of the input files.
  47
  48 class Read_symbols : public Task
  49 {
  50  public:
  51   // DIRPATH is the list of directories to search for libraries.
  52   // INPUT is the file to read.  INPUT_GROUP is not NULL if we are in
  53   // the middle of an input group.  THIS_BLOCKER is used to prevent
  54   // the associated Add_symbols task from running before the previous
  55   // one has completed; it will be NULL for the first task.
  56   // NEXT_BLOCKER is used to block the next input file from adding
  57   // symbols.
  58   Read_symbols(Input_objects* input_objects, Symbol_table* symtab,
  59                Layout* layout, Dirsearch* dirpath, int dirindex,
  60                Mapfile* mapfile, const Input_argument* input_argument,
  61                Input_group* input_group, Task_token* this_blocker,
  62                Task_token* next_blocker)
  63     : input_objects_(input_objects), symtab_(symtab), layout_(layout),
  64       dirpath_(dirpath), dirindex_(dirindex), mapfile_(mapfile),
  65       input_argument_(input_argument), input_group_(input_group),
  66       this_blocker_(this_blocker), next_blocker_(next_blocker)
  67   { }
  68
  69   ~Read_symbols();
  70
  71   // If appropriate, issue a warning about skipping an incompatible
  72   // object.
  73   static void
  74   incompatible_warning(const Input_argument*, const Input_file*);
  75
  76   // Requeue a Read_symbols task to search for the next object with
  77   // the same name.
  78   static void
  79   requeue(Workqueue*, Input_objects*, Symbol_table*, Layout*, Dirsearch*,
  80           int dirindex, Mapfile*, const Input_argument*, Input_group*,
  81           Task_token* next_blocker);
  82
  83   // The standard Task methods.
  84
  85   Task_token*
  86   is_runnable();
  87
  88   void
  89   locks(Task_locker*);
  90
  91   void
  92   run(Workqueue*);
  93
  94   std::string
  95   get_name() const;
  96
  97  private:
  98   // Handle an archive group.
  99   void
 100   do_group(Workqueue*);
 101
 102   // Open and identify the file.
 103   bool
 104   do_read_symbols(Workqueue*);
 105
 106   Input_objects* input_objects_;
 107   Symbol_table* symtab_;
 108   Layout* layout_;
 109   Dirsearch* dirpath_;
 110   int dirindex_;
 111   Mapfile* mapfile_;
 112   const Input_argument* input_argument_;
 113   Input_group* input_group_;
 114   Task_token* this_blocker_;
 115   Task_token* next_blocker_;
 116 };
 117
 118 // This Task handles adding the symbols to the symbol table.  These
 119 // tasks must be run in the same order as the arguments appear on the
 120 // command line.
 121
 122 class Add_symbols : public Task
 123 {
 124  public:
 125   // THIS_BLOCKER is used to prevent this task from running before the
 126   // one for the previous input file.  NEXT_BLOCKER is used to prevent
 127   // the next task from running.
 128   Add_symbols(Input_objects* input_objects, Symbol_table* symtab,
 129               Layout* layout, Dirsearch* dirpath, int dirindex,
 130               Mapfile* mapfile, const Input_argument* input_argument,
 131               Object* object,
 132               Read_symbols_data* sd, Task_token* this_blocker,
 133               Task_token* next_blocker)
 134     : input_objects_(input_objects), symtab_(symtab), layout_(layout),
 135       dirpath_(dirpath), dirindex_(dirindex), mapfile_(mapfile),
 136       input_argument_(input_argument),
 137       object_(object), sd_(sd), this_blocker_(this_blocker),
 138       next_blocker_(next_blocker)
 139   { }
 140
 141   ~Add_symbols();
 142
 143   // The standard Task methods.
 144
 145   Task_token*
 146   is_runnable();
 147
 148   void
 149   locks(Task_locker*);
 150
 151   void
 152   run(Workqueue*);
 153
 154   std::string
 155   get_name() const
 156   { return "Add_symbols " + this->object_->name(); }
 157
 158 private:
 159   Input_objects* input_objects_;
 160   Symbol_table* symtab_;
 161   Layout* layout_;
 162   Dirsearch* dirpath_;
 163   int dirindex_;
 164   Mapfile* mapfile_;
 165   const Input_argument* input_argument_;
 166   Object* object_;
 167   Read_symbols_data* sd_;
 168   Task_token* this_blocker_;
 169   Task_token* next_blocker_;
 170 };
 171
 172 // This class is used to track the archives in a group.
 173
 174 class Input_group
 175 {
 176  public:
 177   typedef std::vector<Archive*> Archives;
 178   typedef Archives::const_iterator const_iterator;
 179
 180   Input_group()
 181     : archives_()
 182   { }
 183
 184   // Add an archive to the group.
 185   void
 186   add_archive(Archive* arch)
 187   { this->archives_.push_back(arch); }
 188
 189   // Loop over the archives in the group.
 190
 191   const_iterator
 192   begin() const
 193   { return this->archives_.begin(); }
 194
 195   const_iterator
 196   end() const
 197   { return this->archives_.end(); }
 198
 199  private:
 200   Archives archives_;
 201 };
 202
 203 // This class starts the handling of a group.  It exists only to pick
 204 // up the number of undefined symbols at that point, so that we only
 205 // run back through the group if we saw a new undefined symbol.
 206
 207 class Start_group : public Task
 208 {
 209  public:
 210   Start_group(Symbol_table* symtab, Finish_group* finish_group,
 211               Task_token* this_blocker, Task_token* next_blocker)
 212     : symtab_(symtab), finish_group_(finish_group),
 213       this_blocker_(this_blocker), next_blocker_(next_blocker)
 214   { }
 215
 216   ~Start_group();
 217
 218   // The standard Task methods.
 219
 220   Task_token*
 221   is_runnable();
 222
 223   void
 224   locks(Task_locker*);
 225
 226   void
 227   run(Workqueue*);
 228
 229   std::string
 230   get_name() const
 231   { return "Start_group"; }
 232
 233  private:
 234   Symbol_table* symtab_;
 235   Finish_group* finish_group_;
 236   Task_token* this_blocker_;
 237   Task_token* next_blocker_;
 238 };
 239
 240 // This class is used to finish up handling a group.  It is just a
 241 // closure.
 242
 243 class Finish_group : public Task
 244 {
 245  public:
 246   Finish_group(Input_objects* input_objects, Symbol_table* symtab,
 247                Layout* layout, Mapfile* mapfile, Input_group* input_group,
 248                Task_token* next_blocker)
 249     : input_objects_(input_objects), symtab_(symtab),
 250       layout_(layout), mapfile_(mapfile), input_group_(input_group),
 251       saw_undefined_(0), this_blocker_(NULL), next_blocker_(next_blocker)
 252   { }
 253
 254   ~Finish_group();
 255
 256   // Set the number of undefined symbols when we start processing the
 257   // group.  This is called by the Start_group task.
 258   void
 259   set_saw_undefined(size_t saw_undefined)
 260   { this->saw_undefined_ = saw_undefined; }
 261
 262   // Set the blocker to use for this task.
 263   void
 264   set_blocker(Task_token* this_blocker)
 265   {
 266     gold_assert(this->this_blocker_ == NULL);
 267     this->this_blocker_ = this_blocker;
 268   }
 269
 270   // The standard Task methods.
 271
 272   Task_token*
 273   is_runnable();
 274
 275   void
 276   locks(Task_locker*);
 277
 278   void
 279   run(Workqueue*);
 280
 281   std::string
 282   get_name() const
 283   { return "Finish_group"; }
 284
 285  private:
 286   Input_objects* input_objects_;
 287   Symbol_table* symtab_;
 288   Layout* layout_;
 289   Mapfile* mapfile_;
 290   Input_group* input_group_;
 291   size_t saw_undefined_;
 292   Task_token* this_blocker_;
 293   Task_token* next_blocker_;
 294 };
 295
 296 // This class is used to read a file which was not recognized as an
 297 // object or archive.  It tries to read it as a linker script, using
 298 // the tokens to serialize with the calls to Add_symbols.
 299
 300 class Read_script : public Task
 301 {
 302  public:
 303   Read_script(Symbol_table* symtab, Layout* layout, Dirsearch* dirpath,
 304               int dirindex, Input_objects* input_objects, Mapfile* mapfile,
 305               Input_group* input_group, const Input_argument* input_argument,
 306               Input_file* input_file, Task_token* this_blocker,
 307               Task_token* next_blocker)
 308     : symtab_(symtab), layout_(layout), dirpath_(dirpath), dirindex_(dirindex),
 309       input_objects_(input_objects), mapfile_(mapfile),
 310       input_group_(input_group), input_argument_(input_argument),
 311       input_file_(input_file), this_blocker_(this_blocker),
 312       next_blocker_(next_blocker)
 313   { }
 314
 315   ~Read_script();
 316
 317   // The standard Task methods.
 318
 319   Task_token*
 320   is_runnable();
 321
 322   void
 323   locks(Task_locker*);
 324
 325   void
 326   run(Workqueue*);
 327
 328   std::string
 329   get_name() const;
 330
 331  private:
 332   Symbol_table* symtab_;
 333   Layout* layout_;
 334   Dirsearch* dirpath_;
 335   int dirindex_;
 336   Input_objects* input_objects_;
 337   Mapfile* mapfile_;
 338   Input_group* input_group_;
 339   const Input_argument* input_argument_;
 340   Input_file* input_file_;
 341   Task_token* this_blocker_;
 342   Task_token* next_blocker_;
 343 };
 344
 345 } // end namespace gold
 346
 347 #endif // !defined(GOLD_READSYMS_H)