]> oss.titaniummirror.com Git - msp430-binutils.git/blobdiff - gold/readsyms.cc
Imported binutils-2.20
[msp430-binutils.git] / gold / readsyms.cc
diff --git a/gold/readsyms.cc b/gold/readsyms.cc
new file mode 100644 (file)
index 0000000..6cff853
--- /dev/null
@@ -0,0 +1,601 @@
+// readsyms.cc -- read input file symbols for gold
+
+// Copyright 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+// Written by Ian Lance Taylor <iant@google.com>.
+
+// This file is part of gold.
+
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+
+#include "gold.h"
+
+#include <cstring>
+
+#include "elfcpp.h"
+#include "options.h"
+#include "dirsearch.h"
+#include "symtab.h"
+#include "object.h"
+#include "archive.h"
+#include "script.h"
+#include "readsyms.h"
+#include "plugin.h"
+#include "layout.h"
+#include "incremental.h"
+
+namespace gold
+{
+
+// If we fail to open the object, then we won't create an Add_symbols
+// task.  However, we still need to unblock the token, or else the
+// link won't proceed to generate more error messages.  We can only
+// unblock tokens when the workqueue lock is held, so we need a dummy
+// task to do that.  The dummy task has to maintain the right sequence
+// of blocks, so we need both this_blocker and next_blocker.
+
+class Unblock_token : public Task
+{
+ public:
+  Unblock_token(Task_token* this_blocker, Task_token* next_blocker)
+    : this_blocker_(this_blocker), next_blocker_(next_blocker)
+  { }
+
+  ~Unblock_token()
+  {
+    if (this->this_blocker_ != NULL)
+      delete this->this_blocker_;
+  }
+
+  Task_token*
+  is_runnable()
+  {
+    if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
+      return this->this_blocker_;
+    return NULL;
+  }
+
+  void
+  locks(Task_locker* tl)
+  { tl->add(this, this->next_blocker_); }
+
+  void
+  run(Workqueue*)
+  { }
+
+  std::string
+  get_name() const
+  { return "Unblock_token"; }
+
+ private:
+  Task_token* this_blocker_;
+  Task_token* next_blocker_;
+};
+
+// Class read_symbols.
+
+Read_symbols::~Read_symbols()
+{
+  // The this_blocker_ and next_blocker_ pointers are passed on to the
+  // Add_symbols task.
+}
+
+// If appropriate, issue a warning about skipping an incompatible
+// file.
+
+void
+Read_symbols::incompatible_warning(const Input_argument* input_argument,
+                                  const Input_file* input_file)
+{
+  if (parameters->options().warn_search_mismatch())
+    gold_warning("skipping incompatible %s while searching for %s",
+                input_file->filename().c_str(),
+                input_argument->file().name());
+}
+
+// Requeue a Read_symbols task to search for the next object with the
+// same name.
+
+void
+Read_symbols::requeue(Workqueue* workqueue, Input_objects* input_objects,
+                     Symbol_table* symtab, Layout* layout, Dirsearch* dirpath,
+                     int dirindex, Mapfile* mapfile,
+                     const Input_argument* input_argument,
+                     Input_group* input_group, Task_token* next_blocker)
+{
+  // Bump the directory search index.
+  ++dirindex;
+
+  // We don't need to worry about this_blocker, since we already
+  // reached it.  However, we are removing the blocker on next_blocker
+  // because the calling task is completing.  So we need to add a new
+  // blocker.  Since next_blocker may be shared by several tasks, we
+  // need to increment the count with the workqueue lock held.
+  workqueue->add_blocker(next_blocker);
+
+  workqueue->queue(new Read_symbols(input_objects, symtab, layout, dirpath,
+                                   dirindex, mapfile, input_argument,
+                                   input_group, NULL, next_blocker));
+}
+
+// Return whether a Read_symbols task is runnable.  We can read an
+// ordinary input file immediately.  For an archive specified using
+// -l, we have to wait until the search path is complete.
+
+Task_token*
+Read_symbols::is_runnable()
+{
+  if (this->input_argument_->is_file()
+      && this->input_argument_->file().may_need_search()
+      && this->dirpath_->token()->is_blocked())
+    return this->dirpath_->token();
+
+  return NULL;
+}
+
+// Return a Task_locker for a Read_symbols task.  We don't need any
+// locks here.
+
+void
+Read_symbols::locks(Task_locker*)
+{
+}
+
+// Run a Read_symbols task.
+
+void
+Read_symbols::run(Workqueue* workqueue)
+{
+  // If we didn't queue a new task, then we need to explicitly unblock
+  // the token.
+  if (!this->do_read_symbols(workqueue))
+    workqueue->queue_soon(new Unblock_token(this->this_blocker_,
+                                           this->next_blocker_));
+}
+
+// Open the file and read the symbols.  Return true if a new task was
+// queued, false if that could not happen due to some error.
+
+bool
+Read_symbols::do_read_symbols(Workqueue* workqueue)
+{
+  if (this->input_argument_->is_group())
+    {
+      gold_assert(this->input_group_ == NULL);
+      this->do_group(workqueue);
+      return true;
+    }
+
+  Input_file* input_file = new Input_file(&this->input_argument_->file());
+  if (!input_file->open(*this->dirpath_, this, &this->dirindex_))
+    return false;
+
+  // Read enough of the file to pick up the entire ELF header.
+
+  off_t filesize = input_file->file().filesize();
+
+  if (filesize == 0)
+    {
+      gold_error(_("%s: file is empty"),
+                input_file->file().filename().c_str());
+      return false;
+    }
+
+  const unsigned char* ehdr;
+  int read_size;
+  bool is_elf = is_elf_object(input_file, 0, &ehdr, &read_size);
+
+  if (read_size >= Archive::sarmag)
+    {
+      bool is_thin_archive
+          = memcmp(ehdr, Archive::armagt, Archive::sarmag) == 0;
+      if (is_thin_archive
+          || memcmp(ehdr, Archive::armag, Archive::sarmag) == 0)
+       {
+         // This is an archive.
+         Archive* arch = new Archive(this->input_argument_->file().name(),
+                                     input_file, is_thin_archive,
+                                     this->dirpath_, this);
+         arch->setup();
+
+         if (this->layout_->incremental_inputs())
+           {
+             const Input_argument* ia = this->input_argument_;       
+             this->layout_->incremental_inputs()->report_archive(ia, arch);
+           }
+
+         // Unlock the archive so it can be used in the next task.
+         arch->unlock(this);
+
+         workqueue->queue_next(new Add_archive_symbols(this->symtab_,
+                                                       this->layout_,
+                                                       this->input_objects_,
+                                                       this->dirpath_,
+                                                       this->dirindex_,
+                                                       this->mapfile_,
+                                                       this->input_argument_,
+                                                       arch,
+                                                       this->input_group_,
+                                                       this->this_blocker_,
+                                                       this->next_blocker_));
+         return true;
+       }
+    }
+
+  if (parameters->options().has_plugins())
+    {
+      Pluginobj* obj = parameters->options().plugins()->claim_file(input_file,
+                                                                   0, filesize);
+      if (obj != NULL)
+        {
+          // The input file was claimed by a plugin, and its symbols
+          // have been provided by the plugin.
+
+          // We are done with the file at this point, so unlock it.
+          obj->unlock(this);
+
+          workqueue->queue_next(new Add_symbols(this->input_objects_,
+                                                this->symtab_,
+                                                this->layout_,
+                                               this->dirpath_,
+                                               this->dirindex_,
+                                               this->mapfile_,
+                                               this->input_argument_,
+                                               this->input_group_,
+                                                obj,
+                                               NULL,
+                                                this->this_blocker_,
+                                                this->next_blocker_));
+          return true;
+        }
+    }
+
+  if (is_elf)
+    {
+      // This is an ELF object.
+
+      bool unconfigured = false;
+      bool* punconfigured = (input_file->will_search_for()
+                            ? &unconfigured
+                            : NULL);
+      Object* obj = make_elf_object(input_file->filename(),
+                                   input_file, 0, ehdr, read_size,
+                                   punconfigured);
+      if (obj == NULL)
+       {
+         if (unconfigured)
+           {
+             Read_symbols::incompatible_warning(this->input_argument_,
+                                                input_file);
+             input_file->file().release();
+             input_file->file().unlock(this);
+             delete input_file;
+             ++this->dirindex_;
+             return this->do_read_symbols(workqueue);
+           }
+         return false;
+       }
+
+      Read_symbols_data* sd = new Read_symbols_data;
+      obj->read_symbols(sd);
+
+      if (this->layout_->incremental_inputs())
+       {
+         const Input_argument* ia = this->input_argument_;
+         this->layout_->incremental_inputs()->report_object(ia, obj);
+       }
+
+      // Opening the file locked it, so now we need to unlock it.  We
+      // need to unlock it before queuing the Add_symbols task,
+      // because the workqueue doesn't know about our lock on the
+      // file.  If we queue the Add_symbols task first, it will be
+      // stuck on the end of the file lock, but since the workqueue
+      // doesn't know about that lock, it will never release the
+      // Add_symbols task.
+
+      input_file->file().unlock(this);
+
+      // We use queue_next because everything is cached for this
+      // task to run right away if possible.
+
+      workqueue->queue_next(new Add_symbols(this->input_objects_,
+                                           this->symtab_, this->layout_,
+                                           this->dirpath_,
+                                           this->dirindex_,
+                                           this->mapfile_,
+                                           this->input_argument_,
+                                           this->input_group_,
+                                           obj,
+                                           sd,
+                                           this->this_blocker_,
+                                           this->next_blocker_));
+
+      return true;
+    }
+
+  // Queue up a task to try to parse this file as a script.  We use a
+  // separate task so that the script will be read in order with other
+  // objects named on the command line.  Also so that we don't try to
+  // read multiple scripts simultaneously, which could lead to
+  // unpredictable changes to the General_options structure.
+
+  workqueue->queue_soon(new Read_script(this->symtab_,
+                                       this->layout_,
+                                       this->dirpath_,
+                                       this->dirindex_,
+                                       this->input_objects_,
+                                       this->mapfile_,
+                                       this->input_group_,
+                                       this->input_argument_,
+                                       input_file,
+                                       this->this_blocker_,
+                                       this->next_blocker_));
+  return true;
+}
+
+// Handle a group.  We need to walk through the arguments over and
+// over until we don't see any new undefined symbols.  We do this by
+// setting off Read_symbols Tasks as usual, but recording the archive
+// entries instead of deleting them.  We also start a Finish_group
+// Task which runs after we've read all the symbols.  In that task we
+// process the archives in a loop until we are done.
+
+void
+Read_symbols::do_group(Workqueue* workqueue)
+{
+  Input_group* input_group = new Input_group();
+
+  const Input_file_group* group = this->input_argument_->group();
+  Task_token* this_blocker = this->this_blocker_;
+
+  for (Input_file_group::const_iterator p = group->begin();
+       p != group->end();
+       ++p)
+    {
+      const Input_argument* arg = &*p;
+      gold_assert(arg->is_file());
+
+      Task_token* next_blocker = new Task_token(true);
+      next_blocker->add_blocker();
+      workqueue->queue_soon(new Read_symbols(this->input_objects_,
+                                            this->symtab_, this->layout_,
+                                            this->dirpath_, this->dirindex_,
+                                            this->mapfile_, arg, input_group,
+                                            this_blocker, next_blocker));
+      this_blocker = next_blocker;
+    }
+
+  const int saw_undefined = this->symtab_->saw_undefined();
+  workqueue->queue_soon(new Finish_group(this->input_objects_,
+                                        this->symtab_,
+                                        this->layout_,
+                                        this->mapfile_,
+                                        input_group,
+                                        saw_undefined,
+                                        this_blocker,
+                                        this->next_blocker_));
+}
+
+// Return a debugging name for a Read_symbols task.
+
+std::string
+Read_symbols::get_name() const
+{
+  if (!this->input_argument_->is_group())
+    {
+      std::string ret("Read_symbols ");
+      if (this->input_argument_->file().is_lib())
+       ret += "-l";
+      else if (this->input_argument_->file().is_searched_file())
+       ret += "-l:";
+      ret += this->input_argument_->file().name();
+      return ret;
+    }
+
+  std::string ret("Read_symbols group (");
+  bool add_space = false;
+  const Input_file_group* group = this->input_argument_->group();
+  for (Input_file_group::const_iterator p = group->begin();
+       p != group->end();
+       ++p)
+    {
+      if (add_space)
+       ret += ' ';
+      ret += p->file().name();
+      add_space = true;
+    }
+  return ret + ')';
+}
+
+// Class Add_symbols.
+
+Add_symbols::~Add_symbols()
+{
+  if (this->this_blocker_ != NULL)
+    delete this->this_blocker_;
+  // next_blocker_ is deleted by the task associated with the next
+  // input file.
+}
+
+// We are blocked by this_blocker_.  We block next_blocker_.  We also
+// lock the file.
+
+Task_token*
+Add_symbols::is_runnable()
+{
+  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
+    return this->this_blocker_;
+  if (this->object_->is_locked())
+    return this->object_->token();
+  return NULL;
+}
+
+void
+Add_symbols::locks(Task_locker* tl)
+{
+  tl->add(this, this->next_blocker_);
+  tl->add(this, this->object_->token());
+}
+
+// Add the symbols in the object to the symbol table.
+
+void
+Add_symbols::run(Workqueue*)
+{
+  Pluginobj* pluginobj = this->object_->pluginobj();
+  if (pluginobj != NULL)
+    {
+      this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
+      return;
+    }
+
+  if (!this->input_objects_->add_object(this->object_))
+    {
+      this->object_->release();
+      delete this->object_;
+    }
+  else
+    {
+      this->object_->layout(this->symtab_, this->layout_, this->sd_);
+      this->object_->add_symbols(this->symtab_, this->sd_, this->layout_);
+      this->object_->release();
+    }
+  delete this->sd_;
+  this->sd_ = NULL;
+}
+
+// Class Finish_group.
+
+Finish_group::~Finish_group()
+{
+  if (this->this_blocker_ != NULL)
+    delete this->this_blocker_;
+  // next_blocker_ is deleted by the task associated with the next
+  // input file following the group.
+}
+
+// We need to wait for THIS_BLOCKER_ and unblock NEXT_BLOCKER_.
+
+Task_token*
+Finish_group::is_runnable()
+{
+  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
+    return this->this_blocker_;
+  return NULL;
+}
+
+void
+Finish_group::locks(Task_locker* tl)
+{
+  tl->add(this, this->next_blocker_);
+}
+
+// Loop over the archives until there are no new undefined symbols.
+
+void
+Finish_group::run(Workqueue*)
+{
+  int saw_undefined = this->saw_undefined_;
+  while (saw_undefined != this->symtab_->saw_undefined())
+    {
+      saw_undefined = this->symtab_->saw_undefined();
+
+      for (Input_group::const_iterator p = this->input_group_->begin();
+          p != this->input_group_->end();
+          ++p)
+       {
+         Task_lock_obj<Archive> tl(this, *p);
+
+         (*p)->add_symbols(this->symtab_, this->layout_,
+                           this->input_objects_, this->mapfile_);
+       }
+    }
+
+  // Delete all the archives now that we no longer need them.
+  for (Input_group::const_iterator p = this->input_group_->begin();
+       p != this->input_group_->end();
+       ++p)
+    delete *p;
+  delete this->input_group_;
+}
+
+// Class Read_script
+
+Read_script::~Read_script()
+{
+  if (this->this_blocker_ != NULL)
+    delete this->this_blocker_;
+  // next_blocker_ is deleted by the task associated with the next
+  // input file.
+}
+
+// We are blocked by this_blocker_.
+
+Task_token*
+Read_script::is_runnable()
+{
+  if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
+    return this->this_blocker_;
+  return NULL;
+}
+
+// We don't unlock next_blocker_ here.  If the script names any input
+// files, then the last file will be responsible for unlocking it.
+
+void
+Read_script::locks(Task_locker*)
+{
+}
+
+// Read the script, if it is a script.
+
+void
+Read_script::run(Workqueue* workqueue)
+{
+  bool used_next_blocker;
+  if (!read_input_script(workqueue, this->symtab_, this->layout_,
+                        this->dirpath_, this->dirindex_, this->input_objects_,
+                        this->mapfile_, this->input_group_,
+                        this->input_argument_, this->input_file_,
+                        this->next_blocker_, &used_next_blocker))
+    {
+      // Here we have to handle any other input file types we need.
+      gold_error(_("%s: not an object or archive"),
+                this->input_file_->file().filename().c_str());
+    }
+
+  if (!used_next_blocker)
+    {
+      // Queue up a task to unlock next_blocker.  We can't just unlock
+      // it here, as we don't hold the workqueue lock.
+      workqueue->queue_soon(new Unblock_token(NULL, this->next_blocker_));
+    }
+}
+
+// Return a debugging name for a Read_script task.
+
+std::string
+Read_script::get_name() const
+{
+  std::string ret("Read_script ");
+  if (this->input_argument_->file().is_lib())
+    ret += "-l";
+  else if (this->input_argument_->file().is_searched_file())
+    ret += "-l:";
+  ret += this->input_argument_->file().name();
+  return ret;
+}
+
+} // End namespace gold.