gold/readsyms.h

   1 // readsyms.h -- read input file symbols for gold   -*- C++ -*-
   2
   3 // Copyright 2006, 2007, 2008, 2009, 2010, 2011 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, Archive_member* member,
  62                Task_token* this_blocker, 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       member_(member), this_blocker_(this_blocker),
  67       next_blocker_(next_blocker)
  68   { }
  69
  70   ~Read_symbols();
  71
  72   // If appropriate, issue a warning about skipping an incompatible
  73   // object.
  74   static void
  75   incompatible_warning(const Input_argument*, const Input_file*);
  76
  77   // Requeue a Read_symbols task to search for the next object with
  78   // the same name.
  79   static void
  80   requeue(Workqueue*, Input_objects*, Symbol_table*, Layout*, Dirsearch*,
  81           int dirindex, Mapfile*, const Input_argument*, Input_group*,
  82           Task_token* next_blocker);
  83
  84   // The standard Task methods.
  85
  86   Task_token*
  87   is_runnable();
  88
  89   void
  90   locks(Task_locker*);
  91
  92   void
  93   run(Workqueue*);
  94
  95   std::string
  96   get_name() const;
  97
  98  private:
  99   // Handle an archive group.
 100   void
 101   do_group(Workqueue*);
 102
 103   // Handle --start-lib ... --end-lib
 104   bool
 105   do_lib_group(Workqueue*);
 106
 107   // Handle --whole-archive --start-lib ... --end-lib --no-whole-archive
 108   bool
 109   do_whole_lib_group(Workqueue*);
 110
 111   // Open and identify the file.
 112   bool
 113   do_read_symbols(Workqueue*);
 114
 115   Input_objects* input_objects_;
 116   Symbol_table* symtab_;
 117   Layout* layout_;
 118   Dirsearch* dirpath_;
 119   int dirindex_;
 120   Mapfile* mapfile_;
 121   const Input_argument* input_argument_;
 122   Input_group* input_group_;
 123   Archive_member* member_;
 124   Task_token* this_blocker_;
 125   Task_token* next_blocker_;
 126 };
 127
 128 // This Task handles adding the symbols to the symbol table.  These
 129 // tasks must be run in the same order as the arguments appear on the
 130 // command line.
 131
 132 class Add_symbols : public Task
 133 {
 134  public:
 135   // THIS_BLOCKER is used to prevent this task from running before the
 136   // one for the previous input file.  NEXT_BLOCKER is used to prevent
 137   // the next task from running.
 138   Add_symbols(Input_objects* input_objects, Symbol_table* symtab,
 139               Layout* layout, Dirsearch* dirpath, int dirindex,
 140               Mapfile* mapfile, const Input_argument* input_argument,
 141               Object* object,
 142               Read_symbols_data* sd, Task_token* this_blocker,
 143               Task_token* next_blocker)
 144     : input_objects_(input_objects), symtab_(symtab), layout_(layout),
 145       dirpath_(dirpath), dirindex_(dirindex), mapfile_(mapfile),
 146       input_argument_(input_argument),
 147       object_(object), sd_(sd), this_blocker_(this_blocker),
 148       next_blocker_(next_blocker)
 149   { }
 150
 151   ~Add_symbols();
 152
 153   // The standard Task methods.
 154
 155   Task_token*
 156   is_runnable();
 157
 158   void
 159   locks(Task_locker*);
 160
 161   void
 162   run(Workqueue*);
 163
 164   std::string
 165   get_name() const
 166   { return "Add_symbols " + this->object_->name(); }
 167
 168 private:
 169   Input_objects* input_objects_;
 170   Symbol_table* symtab_;
 171   Layout* layout_;
 172   Dirsearch* dirpath_;
 173   int dirindex_;
 174   Mapfile* mapfile_;
 175   const Input_argument* input_argument_;
 176   Object* object_;
 177   Read_symbols_data* sd_;
 178   Task_token* this_blocker_;
 179   Task_token* next_blocker_;
 180 };
 181
 182 // This class is used to track the archives in a group.
 183
 184 class Input_group
 185 {
 186  public:
 187   typedef std::vector<Archive*> Archives;
 188   typedef Archives::const_iterator const_iterator;
 189
 190   Input_group()
 191     : archives_()
 192   { }
 193
 194   ~Input_group();
 195
 196   // Add an archive to the group.
 197   void
 198   add_archive(Archive* arch)
 199   { this->archives_.push_back(arch); }
 200
 201   // Loop over the archives in the group.
 202
 203   const_iterator
 204   begin() const
 205   { return this->archives_.begin(); }
 206
 207   const_iterator
 208   end() const
 209   { return this->archives_.end(); }
 210
 211  private:
 212   Archives archives_;
 213 };
 214
 215 // This class starts the handling of a group.  It exists only to pick
 216 // up the number of undefined symbols at that point, so that we only
 217 // run back through the group if we saw a new undefined symbol.
 218
 219 class Start_group : public Task
 220 {
 221  public:
 222   Start_group(Symbol_table* symtab, Finish_group* finish_group,
 223               Task_token* this_blocker, Task_token* next_blocker)
 224     : symtab_(symtab), finish_group_(finish_group),
 225       this_blocker_(this_blocker), next_blocker_(next_blocker)
 226   { }
 227
 228   ~Start_group();
 229
 230   // The standard Task methods.
 231
 232   Task_token*
 233   is_runnable();
 234
 235   void
 236   locks(Task_locker*);
 237
 238   void
 239   run(Workqueue*);
 240
 241   std::string
 242   get_name() const
 243   { return "Start_group"; }
 244
 245  private:
 246   Symbol_table* symtab_;
 247   Finish_group* finish_group_;
 248   Task_token* this_blocker_;
 249   Task_token* next_blocker_;
 250 };
 251
 252 // This class is used to finish up handling a group.  It is just a
 253 // closure.
 254
 255 class Finish_group : public Task
 256 {
 257  public:
 258   Finish_group(Input_objects* input_objects, Symbol_table* symtab,
 259                Layout* layout, Mapfile* mapfile, Input_group* input_group,
 260                Task_token* next_blocker)
 261     : input_objects_(input_objects), symtab_(symtab),
 262       layout_(layout), mapfile_(mapfile), input_group_(input_group),
 263       saw_undefined_(0), this_blocker_(NULL), next_blocker_(next_blocker)
 264   { }
 265
 266   ~Finish_group();
 267
 268   // Set the number of undefined symbols when we start processing the
 269   // group.  This is called by the Start_group task.
 270   void
 271   set_saw_undefined(size_t saw_undefined)
 272   { this->saw_undefined_ = saw_undefined; }
 273
 274   // Set the blocker to use for this task.
 275   void
 276   set_blocker(Task_token* this_blocker)
 277   {
 278     gold_assert(this->this_blocker_ == NULL);
 279     this->this_blocker_ = this_blocker;
 280   }
 281
 282   // The standard Task methods.
 283
 284   Task_token*
 285   is_runnable();
 286
 287   void
 288   locks(Task_locker*);
 289
 290   void
 291   run(Workqueue*);
 292
 293   std::string
 294   get_name() const
 295   { return "Finish_group"; }
 296
 297  private:
 298   Input_objects* input_objects_;
 299   Symbol_table* symtab_;
 300   Layout* layout_;
 301   Mapfile* mapfile_;
 302   Input_group* input_group_;
 303   size_t saw_undefined_;
 304   Task_token* this_blocker_;
 305   Task_token* next_blocker_;
 306 };
 307
 308 // This class is used to read a file which was not recognized as an
 309 // object or archive.  It tries to read it as a linker script, using
 310 // the tokens to serialize with the calls to Add_symbols.
 311
 312 class Read_script : public Task
 313 {
 314  public:
 315   Read_script(Symbol_table* symtab, Layout* layout, Dirsearch* dirpath,
 316               int dirindex, Input_objects* input_objects, Mapfile* mapfile,
 317               Input_group* input_group, const Input_argument* input_argument,
 318               Input_file* input_file, Task_token* this_blocker,
 319               Task_token* next_blocker)
 320     : symtab_(symtab), layout_(layout), dirpath_(dirpath), dirindex_(dirindex),
 321       input_objects_(input_objects), mapfile_(mapfile),
 322       input_group_(input_group), input_argument_(input_argument),
 323       input_file_(input_file), this_blocker_(this_blocker),
 324       next_blocker_(next_blocker)
 325   { }
 326
 327   ~Read_script();
 328
 329   // The standard Task methods.
 330
 331   Task_token*
 332   is_runnable();
 333
 334   void
 335   locks(Task_locker*);
 336
 337   void
 338   run(Workqueue*);
 339
 340   std::string
 341   get_name() const;
 342
 343  private:
 344   Symbol_table* symtab_;
 345   Layout* layout_;
 346   Dirsearch* dirpath_;
 347   int dirindex_;
 348   Input_objects* input_objects_;
 349   Mapfile* mapfile_;
 350   Input_group* input_group_;
 351   const Input_argument* input_argument_;
 352   Input_file* input_file_;
 353   Task_token* this_blocker_;
 354   Task_token* next_blocker_;
 355 };
 356
 357 } // end namespace gold
 358
 359 #endif // !defined(GOLD_READSYMS_H)