// readsyms.cc -- read input file symbols for gold
+// Copyright 2006, 2007, 2008 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 "readsyms.h"
+#include "symtab.h"
#include "object.h"
+#include "archive.h"
+#include "script.h"
+#include "readsyms.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()
// Add_symbols task.
}
-// Return whether a Read_symbols task is runnable. We need write
-// access to the symbol table. We can read an ordinary input file
-// immediately. For an archive specified using -l, we have to wait
-// until the search path is complete.
+// 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::Is_runnable_type
-Read_symbols::is_runnable(Workqueue*)
+Task_token*
+Read_symbols::is_runnable()
{
- if (this->input_.is_lib() && this->dirpath_.token().is_blocked())
- return IS_BLOCKED;
+ if (this->input_argument_->is_file()
+ && this->input_argument_->file().may_need_search()
+ && this->dirpath_->token()->is_blocked())
+ return this->dirpath_->token();
- return IS_RUNNABLE;
+ return NULL;
}
// Return a Task_locker for a Read_symbols task. We don't need any
// locks here.
-Task_locker*
-Read_symbols::locks(Workqueue*)
+void
+Read_symbols::locks(Task_locker*)
{
- return NULL;
}
-// Run a Read_symbols task. This is where we actually read the
-// symbols and relocations.
+// Run a Read_symbols task.
void
Read_symbols::run(Workqueue* workqueue)
{
- Input_file* input_file = new Input_file(this->input_);
- input_file->open(this->options_, this->dirpath_);
+ // 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->options_, *this->dirpath_, this))
+ return false;
// Read enough of the file to pick up the entire ELF header.
- int ehdr_size = elfcpp::Elf_sizes<64>::ehdr_size;
- off_t bytes;
- const unsigned char* p = input_file->file().get_view(0, ehdr_size, &bytes);
- if (bytes >= 4)
+ off_t filesize = input_file->file().filesize();
+
+ if (filesize == 0)
+ {
+ gold_error(_("%s: file is empty"),
+ input_file->file().filename().c_str());
+ return false;
+ }
+
+ int read_size = elfcpp::Elf_sizes<64>::ehdr_size;
+ if (filesize < read_size)
+ read_size = filesize;
+
+ const unsigned char* ehdr = input_file->file().get_view(0, 0, read_size,
+ true, false);
+
+ if (read_size >= 4)
{
static unsigned char elfmagic[4] =
{
elfcpp::ELFMAG0, elfcpp::ELFMAG1,
elfcpp::ELFMAG2, elfcpp::ELFMAG3
};
- if (memcmp(p, elfmagic, 4) == 0)
+ if (memcmp(ehdr, elfmagic, 4) == 0)
{
// This is an ELF object.
- Object* obj = make_elf_object(this->input_.name(), input_file, 0,
- p, bytes);
- this->input_objects_->add_object(obj);
+ Object* obj = make_elf_object(input_file->filename(),
+ input_file, 0, ehdr, read_size);
+ if (obj == NULL)
+ return false;
- Read_symbols_data sd = obj->read_symbols();
- workqueue->queue(new Add_symbols(this->symtab_, obj, sd,
- this->this_blocker_,
- this->next_blocker_));
+ Read_symbols_data* sd = new Read_symbols_data;
+ obj->read_symbols(sd);
// Opening the file locked it, so now we need to unlock it.
- input_file->file().unlock();
+ // 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_,
+ obj, sd,
+ this->this_blocker_,
+ this->next_blocker_));
+
+ return true;
+ }
+ }
+
+ 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();
+
+ // Unlock the archive so it can be used in the next task.
+ arch->unlock(this);
- return;
+ workqueue->queue_next(new Add_archive_symbols(this->symtab_,
+ this->layout_,
+ this->input_objects_,
+ arch,
+ this->input_group_,
+ this->this_blocker_,
+ this->next_blocker_));
+ return true;
}
}
- // Here we have to handle archives and any other input file
- // types we need.
- gold_fatal("only objects are currently supported", false);
+ // 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->options_,
+ this->symtab_,
+ this->layout_,
+ this->dirpath_,
+ this->input_objects_,
+ 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->options_,
+ this->input_objects_,
+ this->symtab_, this->layout_,
+ this->dirpath_, 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_,
+ 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";
+ 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.
// We are blocked by this_blocker_. We block next_blocker_. We also
// lock the file.
-Task::Is_runnable_type
-Add_symbols::is_runnable(Workqueue*)
+Task_token*
+Add_symbols::is_runnable()
{
if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
- return IS_BLOCKED;
+ return this->this_blocker_;
if (this->object_->is_locked())
- return IS_LOCKED;
- return IS_RUNNABLE;
+ return this->object_->token();
+ return NULL;
}
-class Add_symbols::Add_symbols_locker : public Task_locker
+void
+Add_symbols::locks(Task_locker* tl)
{
- public:
- Add_symbols_locker(Task_token& token, Workqueue* workqueue,
- Object* object)
- : blocker_(token, workqueue), objlock_(*object)
- { }
+ tl->add(this, this->next_blocker_);
+ tl->add(this, this->object_->token());
+}
- private:
- Task_locker_block blocker_;
- Task_locker_obj<Object> objlock_;
-};
+// Add the symbols in the object to the symbol table.
+
+void
+Add_symbols::run(Workqueue*)
+{
+ if (!this->input_objects_->add_object(this->object_))
+ {
+ // FIXME: We need to close the descriptor here.
+ delete this->object_;
+ }
+ else
+ {
+ this->object_->layout(this->symtab_, this->layout_, this->sd_);
+ this->object_->add_symbols(this->symtab_, this->sd_);
+ this->object_->release();
+ }
+ delete this->sd_;
+ this->sd_ = NULL;
+}
+
+// Class Finish_group.
-Task_locker*
-Add_symbols::locks(Workqueue* workqueue)
+Finish_group::~Finish_group()
{
- return new Add_symbols_locker(*this->next_blocker_, workqueue,
- this->object_);
+ 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
-Add_symbols::run(Workqueue*)
+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_);
+ }
+ }
+
+ // 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->options_, this->symtab_,
+ this->layout_, this->dirpath_, this->input_objects_,
+ 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
{
- this->object_->add_symbols(this->symtab_, this->sd_);
+ std::string ret("Read_script ");
+ if (this->input_argument_->file().is_lib())
+ ret += "-l";
+ ret += this->input_argument_->file().name();
+ return ret;
}
} // End namespace gold.
projects / deliverable / binutils-gdb.git / blobdiff