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old-cross-binutils/gold/plugin.cc
Sriraman Tallam f0558624db 2011-09-29 Sriraman Tallam <tmsriram@google.com> 
* layout.h (section_order_map_): New member.
	(get_section_order_map): New member function.
	* output.cc (Output_section::add_input_section): Check for patterns
	only when --section-ordering-file is specified.
	* gold.cc (queue_middle_tasks): Delay updating order of sections till
	output_sections have been formed.
	* layout.cc (Layout_Layout): Initialize section_order_map_.
	* plugin.cc (update_section_order): Store order in order_map. Do not
	update the order.
	* testsuite/Makefile.am: Add test case for plugin_final_layout.
	* testsuite/Makefile.in: Regenerate.
	* testsuite/plugin_section_order.c: New file.
	* testsuite/plugin_final_layout.cc: New file.
	* testsuite/plugin_final_layout.sh: New file.
2011-09-29 23:45:57 +00:00

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// plugin.cc -- plugin manager for gold -*- C++ -*-
// Copyright 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
// Written by Cary Coutant <ccoutant@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 <cstdio>
#include <cstdarg>
#include <cstring>
#include <string>
#include <vector>
#ifdef ENABLE_PLUGINS
#include <dlfcn.h>
#endif
#include "parameters.h"
#include "errors.h"
#include "fileread.h"
#include "layout.h"
#include "options.h"
#include "plugin.h"
#include "target.h"
#include "readsyms.h"
#include "symtab.h"
#include "elfcpp.h"
namespace gold
{
#ifdef ENABLE_PLUGINS
// The linker's exported interfaces.
extern "C"
{
static enum ld_plugin_status
register_claim_file(ld_plugin_claim_file_handler handler);
static enum ld_plugin_status
register_all_symbols_read(ld_plugin_all_symbols_read_handler handler);
static enum ld_plugin_status
register_cleanup(ld_plugin_cleanup_handler handler);
static enum ld_plugin_status
add_symbols(void *handle, int nsyms, const struct ld_plugin_symbol *syms);
static enum ld_plugin_status
get_input_file(const void *handle, struct ld_plugin_input_file *file);
static enum ld_plugin_status
get_view(const void *handle, const void **viewp);
static enum ld_plugin_status
release_input_file(const void *handle);
static enum ld_plugin_status
get_symbols(const void *handle, int nsyms, struct ld_plugin_symbol *syms);
static enum ld_plugin_status
get_symbols_v2(const void *handle, int nsyms, struct ld_plugin_symbol *syms);
static enum ld_plugin_status
add_input_file(const char *pathname);
static enum ld_plugin_status
add_input_library(const char *pathname);
static enum ld_plugin_status
set_extra_library_path(const char *path);
static enum ld_plugin_status
message(int level, const char *format, ...);
static enum ld_plugin_status
get_input_section_count(const void* handle, unsigned int* count);
static enum ld_plugin_status
get_input_section_type(const struct ld_plugin_section section,
unsigned int* type);
static enum ld_plugin_status
get_input_section_name(const struct ld_plugin_section section,
char** section_name_ptr);
static enum ld_plugin_status
get_input_section_contents(const struct ld_plugin_section section,
const unsigned char** section_contents,
size_t* len);
static enum ld_plugin_status
update_section_order(const struct ld_plugin_section *section_list,
unsigned int num_sections);
static enum ld_plugin_status
allow_section_ordering();
};
#endif // ENABLE_PLUGINS
static Pluginobj* make_sized_plugin_object(Input_file* input_file,
off_t offset, off_t filesize);
// Plugin methods.
// Load one plugin library.
void
Plugin::load()
{
#ifdef ENABLE_PLUGINS
// Load the plugin library.
// FIXME: Look for the library in standard locations.
this->handle_ = dlopen(this->filename_.c_str(), RTLD_NOW);
if (this->handle_ == NULL)
{
gold_error(_("%s: could not load plugin library: %s"),
this->filename_.c_str(), dlerror());
return;
}
// Find the plugin's onload entry point.
void* ptr = dlsym(this->handle_, "onload");
if (ptr == NULL)
{
gold_error(_("%s: could not find onload entry point"),
this->filename_.c_str());
return;
}
ld_plugin_onload onload;
gold_assert(sizeof(onload) == sizeof(ptr));
memcpy(&onload, &ptr, sizeof(ptr));
// Get the linker's version number.
const char* ver = get_version_string();
int major = 0;
int minor = 0;
sscanf(ver, "%d.%d", &major, &minor);
// Allocate and populate a transfer vector.
const int tv_fixed_size = 24;
int tv_size = this->args_.size() + tv_fixed_size;
ld_plugin_tv* tv = new ld_plugin_tv[tv_size];
// Put LDPT_MESSAGE at the front of the list so the plugin can use it
// while processing subsequent entries.
int i = 0;
tv[i].tv_tag = LDPT_MESSAGE;
tv[i].tv_u.tv_message = message;
++i;
tv[i].tv_tag = LDPT_API_VERSION;
tv[i].tv_u.tv_val = LD_PLUGIN_API_VERSION;
++i;
tv[i].tv_tag = LDPT_GOLD_VERSION;
tv[i].tv_u.tv_val = major * 100 + minor;
++i;
tv[i].tv_tag = LDPT_LINKER_OUTPUT;
if (parameters->options().relocatable())
tv[i].tv_u.tv_val = LDPO_REL;
else if (parameters->options().shared())
tv[i].tv_u.tv_val = LDPO_DYN;
else
tv[i].tv_u.tv_val = LDPO_EXEC;
++i;
tv[i].tv_tag = LDPT_OUTPUT_NAME;
tv[i].tv_u.tv_string = parameters->options().output();
for (unsigned int j = 0; j < this->args_.size(); ++j)
{
++i;
tv[i].tv_tag = LDPT_OPTION;
tv[i].tv_u.tv_string = this->args_[j].c_str();
}
++i;
tv[i].tv_tag = LDPT_REGISTER_CLAIM_FILE_HOOK;
tv[i].tv_u.tv_register_claim_file = register_claim_file;
++i;
tv[i].tv_tag = LDPT_REGISTER_ALL_SYMBOLS_READ_HOOK;
tv[i].tv_u.tv_register_all_symbols_read = register_all_symbols_read;
++i;
tv[i].tv_tag = LDPT_REGISTER_CLEANUP_HOOK;
tv[i].tv_u.tv_register_cleanup = register_cleanup;
++i;
tv[i].tv_tag = LDPT_ADD_SYMBOLS;
tv[i].tv_u.tv_add_symbols = add_symbols;
++i;
tv[i].tv_tag = LDPT_GET_INPUT_FILE;
tv[i].tv_u.tv_get_input_file = get_input_file;
++i;
tv[i].tv_tag = LDPT_GET_VIEW;
tv[i].tv_u.tv_get_view = get_view;
++i;
tv[i].tv_tag = LDPT_RELEASE_INPUT_FILE;
tv[i].tv_u.tv_release_input_file = release_input_file;
++i;
tv[i].tv_tag = LDPT_GET_SYMBOLS;
tv[i].tv_u.tv_get_symbols = get_symbols;
++i;
tv[i].tv_tag = LDPT_GET_SYMBOLS_V2;
tv[i].tv_u.tv_get_symbols = get_symbols_v2;
++i;
tv[i].tv_tag = LDPT_ADD_INPUT_FILE;
tv[i].tv_u.tv_add_input_file = add_input_file;
++i;
tv[i].tv_tag = LDPT_ADD_INPUT_LIBRARY;
tv[i].tv_u.tv_add_input_library = add_input_library;
++i;
tv[i].tv_tag = LDPT_SET_EXTRA_LIBRARY_PATH;
tv[i].tv_u.tv_set_extra_library_path = set_extra_library_path;
++i;
tv[i].tv_tag = LDPT_GET_INPUT_SECTION_COUNT;
tv[i].tv_u.tv_get_input_section_count = get_input_section_count;
++i;
tv[i].tv_tag = LDPT_GET_INPUT_SECTION_TYPE;
tv[i].tv_u.tv_get_input_section_type = get_input_section_type;
++i;
tv[i].tv_tag = LDPT_GET_INPUT_SECTION_NAME;
tv[i].tv_u.tv_get_input_section_name = get_input_section_name;
++i;
tv[i].tv_tag = LDPT_GET_INPUT_SECTION_CONTENTS;
tv[i].tv_u.tv_get_input_section_contents = get_input_section_contents;
++i;
tv[i].tv_tag = LDPT_UPDATE_SECTION_ORDER;
tv[i].tv_u.tv_update_section_order = update_section_order;
++i;
tv[i].tv_tag = LDPT_ALLOW_SECTION_ORDERING;
tv[i].tv_u.tv_allow_section_ordering = allow_section_ordering;
++i;
tv[i].tv_tag = LDPT_NULL;
tv[i].tv_u.tv_val = 0;
gold_assert(i == tv_size - 1);
// Call the onload entry point.
(*onload)(tv);
delete[] tv;
#endif // ENABLE_PLUGINS
}
// Call the plugin claim-file handler.
inline bool
Plugin::claim_file(struct ld_plugin_input_file* plugin_input_file)
{
int claimed = 0;
if (this->claim_file_handler_ != NULL)
{
(*this->claim_file_handler_)(plugin_input_file, &claimed);
if (claimed)
return true;
}
return false;
}
// Call the all-symbols-read handler.
inline void
Plugin::all_symbols_read()
{
if (this->all_symbols_read_handler_ != NULL)
(*this->all_symbols_read_handler_)();
}
// Call the cleanup handler.
inline void
Plugin::cleanup()
{
if (this->cleanup_handler_ != NULL && !this->cleanup_done_)
{
// Set this flag before calling to prevent a recursive plunge
// in the event that a plugin's cleanup handler issues a
// fatal error.
this->cleanup_done_ = true;
(*this->cleanup_handler_)();
}
}
// This task is used to rescan archives as needed.
class Plugin_rescan : public Task
{
public:
Plugin_rescan(Task_token* this_blocker, Task_token* next_blocker)
: this_blocker_(this_blocker), next_blocker_(next_blocker)
{ }
~Plugin_rescan()
{
delete this->this_blocker_;
}
Task_token*
is_runnable()
{
if (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*)
{ parameters->options().plugins()->rescan(this); }
std::string
get_name() const
{ return "Plugin_rescan"; }
private:
Task_token* this_blocker_;
Task_token* next_blocker_;
};
// Plugin_manager methods.
Plugin_manager::~Plugin_manager()
{
for (Plugin_list::iterator p = this->plugins_.begin();
p != this->plugins_.end();
++p)
delete *p;
this->plugins_.clear();
for (Object_list::iterator obj = this->objects_.begin();
obj != this->objects_.end();
++obj)
delete *obj;
this->objects_.clear();
}
// Load all plugin libraries.
void
Plugin_manager::load_plugins(Layout* layout)
{
this->layout_ = layout;
for (this->current_ = this->plugins_.begin();
this->current_ != this->plugins_.end();
++this->current_)
(*this->current_)->load();
}
// Call the plugin claim-file handlers in turn to see if any claim the file.
Pluginobj*
Plugin_manager::claim_file(Input_file* input_file, off_t offset,
off_t filesize, Object* elf_object)
{
if (this->in_replacement_phase_)
return NULL;
unsigned int handle = this->objects_.size();
this->input_file_ = input_file;
this->plugin_input_file_.name = input_file->filename().c_str();
this->plugin_input_file_.fd = input_file->file().descriptor();
this->plugin_input_file_.offset = offset;
this->plugin_input_file_.filesize = filesize;
this->plugin_input_file_.handle = reinterpret_cast<void*>(handle);
if (elf_object != NULL)
this->objects_.push_back(elf_object);
this->in_claim_file_handler_ = true;
for (this->current_ = this->plugins_.begin();
this->current_ != this->plugins_.end();
++this->current_)
{
if ((*this->current_)->claim_file(&this->plugin_input_file_))
{
this->any_claimed_ = true;
this->in_claim_file_handler_ = false;
if (this->objects_.size() > handle
&& this->objects_[handle]->pluginobj() != NULL)
return this->objects_[handle]->pluginobj();
// If the plugin claimed the file but did not call the
// add_symbols callback, we need to create the Pluginobj now.
Pluginobj* obj = this->make_plugin_object(handle);
return obj;
}
}
this->in_claim_file_handler_ = false;
return NULL;
}
// Save an archive. This is used so that a plugin can add a file
// which refers to a symbol which was not previously referenced. In
// that case we want to pretend that the symbol was referenced before,
// and pull in the archive object.
void
Plugin_manager::save_archive(Archive* archive)
{
if (this->in_replacement_phase_ || !this->any_claimed_)
delete archive;
else
this->rescannable_.push_back(Rescannable(archive));
}
// Save an Input_group. This is like save_archive.
void
Plugin_manager::save_input_group(Input_group* input_group)
{
if (this->in_replacement_phase_ || !this->any_claimed_)
delete input_group;
else
this->rescannable_.push_back(Rescannable(input_group));
}
// Call the all-symbols-read handlers.
void
Plugin_manager::all_symbols_read(Workqueue* workqueue, Task* task,
Input_objects* input_objects,
Symbol_table* symtab,
Dirsearch* dirpath, Mapfile* mapfile,
Task_token** last_blocker)
{
this->in_replacement_phase_ = true;
this->workqueue_ = workqueue;
this->task_ = task;
this->input_objects_ = input_objects;
this->symtab_ = symtab;
this->dirpath_ = dirpath;
this->mapfile_ = mapfile;
this->this_blocker_ = NULL;
for (this->current_ = this->plugins_.begin();
this->current_ != this->plugins_.end();
++this->current_)
(*this->current_)->all_symbols_read();
if (this->any_added_)
{
Task_token* next_blocker = new Task_token(true);
next_blocker->add_blocker();
workqueue->queue(new Plugin_rescan(this->this_blocker_, next_blocker));
this->this_blocker_ = next_blocker;
}
*last_blocker = this->this_blocker_;
}
// This is called when we see a new undefined symbol. If we are in
// the replacement phase, this means that we may need to rescan some
// archives we have previously seen.
void
Plugin_manager::new_undefined_symbol(Symbol* sym)
{
if (this->in_replacement_phase_)
this->undefined_symbols_.push_back(sym);
}
// Rescan archives as needed. This handles the case where a new
// object file added by a plugin has an undefined reference to some
// symbol defined in an archive.
void
Plugin_manager::rescan(Task* task)
{
size_t rescan_pos = 0;
size_t rescan_size = this->rescannable_.size();
while (!this->undefined_symbols_.empty())
{
if (rescan_pos >= rescan_size)
{
this->undefined_symbols_.clear();
return;
}
Undefined_symbol_list undefs;
undefs.reserve(this->undefined_symbols_.size());
this->undefined_symbols_.swap(undefs);
size_t min_rescan_pos = rescan_size;
for (Undefined_symbol_list::const_iterator p = undefs.begin();
p != undefs.end();
++p)
{
if (!(*p)->is_undefined())
continue;
this->undefined_symbols_.push_back(*p);
// Find the first rescan archive which defines this symbol,
// starting at the current rescan position. The rescan position
// exists so that given -la -lb -lc we don't look for undefined
// symbols in -lb back in -la, but instead get the definition
// from -lc. Don't bother to look past the current minimum
// rescan position.
for (size_t i = rescan_pos; i < min_rescan_pos; ++i)
{
if (this->rescannable_defines(i, *p))
{
min_rescan_pos = i;
break;
}
}
}
if (min_rescan_pos >= rescan_size)
{
// We didn't find any rescannable archives which define any
// undefined symbols.
return;
}
const Rescannable& r(this->rescannable_[min_rescan_pos]);
if (r.is_archive)
{
Task_lock_obj<Archive> tl(task, r.u.archive);
r.u.archive->add_symbols(this->symtab_, this->layout_,
this->input_objects_, this->mapfile_);
}
else
{
size_t next_saw_undefined = this->symtab_->saw_undefined();
size_t saw_undefined;
do
{
saw_undefined = next_saw_undefined;
for (Input_group::const_iterator p = r.u.input_group->begin();
p != r.u.input_group->end();
++p)
{
Task_lock_obj<Archive> tl(task, *p);
(*p)->add_symbols(this->symtab_, this->layout_,
this->input_objects_, this->mapfile_);
}
next_saw_undefined = this->symtab_->saw_undefined();
}
while (saw_undefined != next_saw_undefined);
}
for (size_t i = rescan_pos; i < min_rescan_pos + 1; ++i)
{
if (this->rescannable_[i].is_archive)
delete this->rescannable_[i].u.archive;
else
delete this->rescannable_[i].u.input_group;
}
rescan_pos = min_rescan_pos + 1;
}
}
// Return whether the rescannable at index I defines SYM.
bool
Plugin_manager::rescannable_defines(size_t i, Symbol* sym)
{
const Rescannable& r(this->rescannable_[i]);
if (r.is_archive)
return r.u.archive->defines_symbol(sym);
else
{
for (Input_group::const_iterator p = r.u.input_group->begin();
p != r.u.input_group->end();
++p)
{
if ((*p)->defines_symbol(sym))
return true;
}
return false;
}
}
// Layout deferred objects.
void
Plugin_manager::layout_deferred_objects()
{
Deferred_layout_list::iterator obj;
for (obj = this->deferred_layout_objects_.begin();
obj != this->deferred_layout_objects_.end();
++obj)
{
// Lock the object so we can read from it. This is only called
// single-threaded from queue_middle_tasks, so it is OK to lock.
// Unfortunately we have no way to pass in a Task token.
const Task* dummy_task = reinterpret_cast<const Task*>(-1);
Task_lock_obj<Object> tl(dummy_task, *obj);
(*obj)->layout_deferred_sections(this->layout_);
}
}
// Call the cleanup handlers.
void
Plugin_manager::cleanup()
{
for (this->current_ = this->plugins_.begin();
this->current_ != this->plugins_.end();
++this->current_)
(*this->current_)->cleanup();
}
// Make a new Pluginobj object. This is called when the plugin calls
// the add_symbols API.
Pluginobj*
Plugin_manager::make_plugin_object(unsigned int handle)
{
// Make sure we aren't asked to make an object for the same handle twice.
if (this->objects_.size() != handle
&& this->objects_[handle]->pluginobj() != NULL)
return NULL;
Pluginobj* obj = make_sized_plugin_object(this->input_file_,
this->plugin_input_file_.offset,
this->plugin_input_file_.filesize);
// If the elf object for this file was pushed into the objects_ vector, delete
// it to make room for the Pluginobj as this file is claimed.
if (this->objects_.size() != handle)
this->objects_.pop_back();
this->objects_.push_back(obj);
return obj;
}
// Get the input file information with an open (possibly re-opened)
// file descriptor.
ld_plugin_status
Plugin_manager::get_input_file(unsigned int handle,
struct ld_plugin_input_file* file)
{
Pluginobj* obj = this->object(handle)->pluginobj();
if (obj == NULL)
return LDPS_BAD_HANDLE;
obj->lock(this->task_);
file->name = obj->filename().c_str();
file->fd = obj->descriptor();
file->offset = obj->offset();
file->filesize = obj->filesize();
file->handle = reinterpret_cast<void*>(handle);
return LDPS_OK;
}
// Release the input file.
ld_plugin_status
Plugin_manager::release_input_file(unsigned int handle)
{
if (this->object(handle) == NULL)
return LDPS_BAD_HANDLE;
Pluginobj* obj = this->object(handle)->pluginobj();
if (obj == NULL)
return LDPS_BAD_HANDLE;
obj->unlock(this->task_);
return LDPS_OK;
}
// Get the elf object corresponding to the handle. Return NULL if we
// found a Pluginobj instead.
Object*
Plugin_manager::get_elf_object(const void* handle)
{
Object* obj = this->object(
static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
// The object should not be a Pluginobj.
if (obj == NULL
|| obj->pluginobj() != NULL)
return NULL;
return obj;
}
ld_plugin_status
Plugin_manager::get_view(unsigned int handle, const void **viewp)
{
off_t offset;
size_t filesize;
Input_file *input_file;
if (this->in_claim_file_handler_)
{
// We are being called from the claim_file hook.
const struct ld_plugin_input_file &f = this->plugin_input_file_;
offset = f.offset;
filesize = f.filesize;
input_file = this->input_file_;
}
else
{
// An already claimed file.
if (this->object(handle) == NULL)
return LDPS_BAD_HANDLE;
Pluginobj* obj = this->object(handle)->pluginobj();
if (obj == NULL)
return LDPS_BAD_HANDLE;
offset = obj->offset();
filesize = obj->filesize();
input_file = obj->input_file();
}
*viewp = (void*) input_file->file().get_view(offset, 0, filesize, false,
false);
return LDPS_OK;
}
// Add a new library path.
ld_plugin_status
Plugin_manager::set_extra_library_path(const char* path)
{
this->extra_search_path_ = std::string(path);
return LDPS_OK;
}
// Add a new input file.
ld_plugin_status
Plugin_manager::add_input_file(const char* pathname, bool is_lib)
{
Input_file_argument file(pathname,
(is_lib
? Input_file_argument::INPUT_FILE_TYPE_LIBRARY
: Input_file_argument::INPUT_FILE_TYPE_FILE),
(is_lib
? this->extra_search_path_.c_str()
: ""),
false,
this->options_);
Input_argument* input_argument = new Input_argument(file);
Task_token* next_blocker = new Task_token(true);
next_blocker->add_blocker();
if (parameters->incremental())
gold_error(_("input files added by plug-ins in --incremental mode not "
"supported yet"));
this->workqueue_->queue_soon(new Read_symbols(this->input_objects_,
this->symtab_,
this->layout_,
this->dirpath_,
0,
this->mapfile_,
input_argument,
NULL,
NULL,
this->this_blocker_,
next_blocker));
this->this_blocker_ = next_blocker;
this->any_added_ = true;
return LDPS_OK;
}
// Class Pluginobj.
Pluginobj::Pluginobj(const std::string& name, Input_file* input_file,
off_t offset, off_t filesize)
: Object(name, input_file, false, offset),
nsyms_(0), syms_(NULL), symbols_(), filesize_(filesize), comdat_map_()
{
}
// Return TRUE if a defined symbol is referenced from outside the
// universe of claimed objects.
static inline bool
is_referenced_from_outside(Symbol* lsym)
{
if (lsym->in_real_elf())
return true;
if (parameters->options().relocatable())
return true;
if (parameters->options().is_undefined(lsym->name()))
return true;
return false;
}
// Return TRUE if a defined symbol might be reachable from outside the
// load module.
static inline bool
is_visible_from_outside(Symbol* lsym)
{
if (parameters->options().export_dynamic() || parameters->options().shared())
return lsym->is_externally_visible();
return false;
}
// Get symbol resolution info.
ld_plugin_status
Pluginobj::get_symbol_resolution_info(int nsyms,
ld_plugin_symbol* syms,
int version) const
{
// For version 1 of this interface, we cannot use
// LDPR_PREVAILING_DEF_IRONLY_EXP, so we return LDPR_PREVAILING_DEF
// instead.
const ld_plugin_symbol_resolution ldpr_prevailing_def_ironly_exp
= (version > 1
? LDPR_PREVAILING_DEF_IRONLY_EXP
: LDPR_PREVAILING_DEF);
if (nsyms > this->nsyms_)
return LDPS_NO_SYMS;
if (static_cast<size_t>(nsyms) > this->symbols_.size())
{
// We never decided to include this object. We mark all symbols as
// preempted.
gold_assert(this->symbols_.size() == 0);
for (int i = 0; i < nsyms; i++)
syms[i].resolution = LDPR_PREEMPTED_REG;
return LDPS_OK;
}
for (int i = 0; i < nsyms; i++)
{
ld_plugin_symbol* isym = &syms[i];
Symbol* lsym = this->symbols_[i];
ld_plugin_symbol_resolution res = LDPR_UNKNOWN;
if (lsym->is_undefined())
// The symbol remains undefined.
res = LDPR_UNDEF;
else if (isym->def == LDPK_UNDEF
|| isym->def == LDPK_WEAKUNDEF
|| isym->def == LDPK_COMMON)
{
// The original symbol was undefined or common.
if (lsym->source() != Symbol::FROM_OBJECT)
res = LDPR_RESOLVED_EXEC;
else if (lsym->object()->pluginobj() == this)
{
if (is_referenced_from_outside(lsym))
res = LDPR_PREVAILING_DEF;
else if (is_visible_from_outside(lsym))
res = ldpr_prevailing_def_ironly_exp;
else
res = LDPR_PREVAILING_DEF_IRONLY;
}
else if (lsym->object()->pluginobj() != NULL)
res = LDPR_RESOLVED_IR;
else if (lsym->object()->is_dynamic())
res = LDPR_RESOLVED_DYN;
else
res = LDPR_RESOLVED_EXEC;
}
else
{
// The original symbol was a definition.
if (lsym->source() != Symbol::FROM_OBJECT)
res = LDPR_PREEMPTED_REG;
else if (lsym->object() == static_cast<const Object*>(this))
{
if (is_referenced_from_outside(lsym))
res = LDPR_PREVAILING_DEF;
else if (is_visible_from_outside(lsym))
res = ldpr_prevailing_def_ironly_exp;
else
res = LDPR_PREVAILING_DEF_IRONLY;
}
else
res = (lsym->object()->pluginobj() != NULL
? LDPR_PREEMPTED_IR
: LDPR_PREEMPTED_REG);
}
isym->resolution = res;
}
return LDPS_OK;
}
// Return TRUE if the comdat group with key COMDAT_KEY from this object
// should be kept.
bool
Pluginobj::include_comdat_group(std::string comdat_key, Layout* layout)
{
std::pair<Comdat_map::iterator, bool> ins =
this->comdat_map_.insert(std::make_pair(comdat_key, false));
// If this is the first time we've seen this comdat key, ask the
// layout object whether it should be included.
if (ins.second)
ins.first->second = layout->find_or_add_kept_section(comdat_key,
NULL, 0, true,
true, NULL);
return ins.first->second;
}
// Class Sized_pluginobj.
template<int size, bool big_endian>
Sized_pluginobj<size, big_endian>::Sized_pluginobj(
const std::string& name,
Input_file* input_file,
off_t offset,
off_t filesize)
: Pluginobj(name, input_file, offset, filesize)
{
}
// Read the symbols. Not used for plugin objects.
template<int size, bool big_endian>
void
Sized_pluginobj<size, big_endian>::do_read_symbols(Read_symbols_data*)
{
gold_unreachable();
}
// Lay out the input sections. Not used for plugin objects.
template<int size, bool big_endian>
void
Sized_pluginobj<size, big_endian>::do_layout(Symbol_table*, Layout*,
Read_symbols_data*)
{
gold_unreachable();
}
// Add the symbols to the symbol table.
template<int size, bool big_endian>
void
Sized_pluginobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
Read_symbols_data*,
Layout* layout)
{
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
unsigned char symbuf[sym_size];
elfcpp::Sym<size, big_endian> sym(symbuf);
elfcpp::Sym_write<size, big_endian> osym(symbuf);
typedef typename elfcpp::Elf_types<size>::Elf_WXword Elf_size_type;
this->symbols_.resize(this->nsyms_);
for (int i = 0; i < this->nsyms_; ++i)
{
const struct ld_plugin_symbol* isym = &this->syms_[i];
const char* name = isym->name;
const char* ver = isym->version;
elfcpp::Elf_Half shndx;
elfcpp::STB bind;
elfcpp::STV vis;
if (name != NULL && name[0] == '\0')
name = NULL;
if (ver != NULL && ver[0] == '\0')
ver = NULL;
switch (isym->def)
{
case LDPK_WEAKDEF:
case LDPK_WEAKUNDEF:
bind = elfcpp::STB_WEAK;
break;
case LDPK_DEF:
case LDPK_UNDEF:
case LDPK_COMMON:
default:
bind = elfcpp::STB_GLOBAL;
break;
}
switch (isym->def)
{
case LDPK_DEF:
case LDPK_WEAKDEF:
shndx = elfcpp::SHN_ABS;
break;
case LDPK_COMMON:
shndx = elfcpp::SHN_COMMON;
break;
case LDPK_UNDEF:
case LDPK_WEAKUNDEF:
default:
shndx = elfcpp::SHN_UNDEF;
break;
}
switch (isym->visibility)
{
case LDPV_PROTECTED:
vis = elfcpp::STV_PROTECTED;
break;
case LDPV_INTERNAL:
vis = elfcpp::STV_INTERNAL;
break;
case LDPV_HIDDEN:
vis = elfcpp::STV_HIDDEN;
break;
case LDPV_DEFAULT:
default:
vis = elfcpp::STV_DEFAULT;
break;
}
if (isym->comdat_key != NULL
&& isym->comdat_key[0] != '\0'
&& !this->include_comdat_group(isym->comdat_key, layout))
shndx = elfcpp::SHN_UNDEF;
osym.put_st_name(0);
osym.put_st_value(0);
osym.put_st_size(static_cast<Elf_size_type>(isym->size));
osym.put_st_info(bind, elfcpp::STT_NOTYPE);
osym.put_st_other(vis, 0);
osym.put_st_shndx(shndx);
this->symbols_[i] =
symtab->add_from_pluginobj<size, big_endian>(this, name, ver, &sym);
}
}
template<int size, bool big_endian>
Archive::Should_include
Sized_pluginobj<size, big_endian>::do_should_include_member(
Symbol_table* symtab,
Layout* layout,
Read_symbols_data*,
std::string* why)
{
char* tmpbuf = NULL;
size_t tmpbuflen = 0;
for (int i = 0; i < this->nsyms_; ++i)
{
const struct ld_plugin_symbol& sym = this->syms_[i];
const char* name = sym.name;
Symbol* symbol;
Archive::Should_include t = Archive::should_include_member(symtab,
layout,
name,
&symbol, why,
&tmpbuf,
&tmpbuflen);
if (t == Archive::SHOULD_INCLUDE_YES)
{
if (tmpbuf != NULL)
free(tmpbuf);
return t;
}
}
if (tmpbuf != NULL)
free(tmpbuf);
return Archive::SHOULD_INCLUDE_UNKNOWN;
}
// Iterate over global symbols, calling a visitor class V for each.
template<int size, bool big_endian>
void
Sized_pluginobj<size, big_endian>::do_for_all_global_symbols(
Read_symbols_data*,
Library_base::Symbol_visitor_base* v)
{
for (int i = 0; i < this->nsyms_; ++i)
{
const struct ld_plugin_symbol& sym = this->syms_[i];
if (sym.def != LDPK_UNDEF)
v->visit(sym.name);
}
}
// Iterate over local symbols, calling a visitor class V for each GOT offset
// associated with a local symbol.
template<int size, bool big_endian>
void
Sized_pluginobj<size, big_endian>::do_for_all_local_got_entries(
Got_offset_list::Visitor*) const
{
gold_unreachable();
}
// Get the size of a section. Not used for plugin objects.
template<int size, bool big_endian>
uint64_t
Sized_pluginobj<size, big_endian>::do_section_size(unsigned int)
{
gold_unreachable();
return 0;
}
// Get the name of a section. Not used for plugin objects.
template<int size, bool big_endian>
std::string
Sized_pluginobj<size, big_endian>::do_section_name(unsigned int)
{
gold_unreachable();
return std::string();
}
// Return a view of the contents of a section. Not used for plugin objects.
template<int size, bool big_endian>
Object::Location
Sized_pluginobj<size, big_endian>::do_section_contents(unsigned int)
{
Location loc(0, 0);
gold_unreachable();
return loc;
}
// Return section flags. Not used for plugin objects.
template<int size, bool big_endian>
uint64_t
Sized_pluginobj<size, big_endian>::do_section_flags(unsigned int)
{
gold_unreachable();
return 0;
}
// Return section entsize. Not used for plugin objects.
template<int size, bool big_endian>
uint64_t
Sized_pluginobj<size, big_endian>::do_section_entsize(unsigned int)
{
gold_unreachable();
return 0;
}
// Return section address. Not used for plugin objects.
template<int size, bool big_endian>
uint64_t
Sized_pluginobj<size, big_endian>::do_section_address(unsigned int)
{
gold_unreachable();
return 0;
}
// Return section type. Not used for plugin objects.
template<int size, bool big_endian>
unsigned int
Sized_pluginobj<size, big_endian>::do_section_type(unsigned int)
{
gold_unreachable();
return 0;
}
// Return the section link field. Not used for plugin objects.
template<int size, bool big_endian>
unsigned int
Sized_pluginobj<size, big_endian>::do_section_link(unsigned int)
{
gold_unreachable();
return 0;
}
// Return the section link field. Not used for plugin objects.
template<int size, bool big_endian>
unsigned int
Sized_pluginobj<size, big_endian>::do_section_info(unsigned int)
{
gold_unreachable();
return 0;
}
// Return the section alignment. Not used for plugin objects.
template<int size, bool big_endian>
uint64_t
Sized_pluginobj<size, big_endian>::do_section_addralign(unsigned int)
{
gold_unreachable();
return 0;
}
// Return the Xindex structure to use. Not used for plugin objects.
template<int size, bool big_endian>
Xindex*
Sized_pluginobj<size, big_endian>::do_initialize_xindex()
{
gold_unreachable();
return NULL;
}
// Get symbol counts. Not used for plugin objects.
template<int size, bool big_endian>
void
Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(const Symbol_table*,
size_t*, size_t*) const
{
gold_unreachable();
}
// Get symbols. Not used for plugin objects.
template<int size, bool big_endian>
const Object::Symbols*
Sized_pluginobj<size, big_endian>::do_get_global_symbols() const
{
gold_unreachable();
}
// Class Plugin_finish. This task runs after all replacement files have
// been added. For now, it's a placeholder for a possible plugin API
// to allow the plugin to release most of its resources. The cleanup
// handlers must be called later, because they can remove the temporary
// object files that are needed until the end of the link.
class Plugin_finish : public Task
{
public:
Plugin_finish(Task_token* this_blocker, Task_token* next_blocker)
: this_blocker_(this_blocker), next_blocker_(next_blocker)
{ }
~Plugin_finish()
{
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*)
{
// We could call early cleanup handlers here.
}
std::string
get_name() const
{ return "Plugin_finish"; }
private:
Task_token* this_blocker_;
Task_token* next_blocker_;
};
// Class Plugin_hook.
Plugin_hook::~Plugin_hook()
{
}
// Return whether a Plugin_hook task is runnable.
Task_token*
Plugin_hook::is_runnable()
{
if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
return this->this_blocker_;
return NULL;
}
// Return a Task_locker for a Plugin_hook task. We don't need any
// locks here.
void
Plugin_hook::locks(Task_locker*)
{
}
// Run the "all symbols read" plugin hook.
void
Plugin_hook::run(Workqueue* workqueue)
{
gold_assert(this->options_.has_plugins());
Symbol* start_sym = this->symtab_->lookup(parameters->entry());
if (start_sym != NULL)
start_sym->set_in_real_elf();
this->options_.plugins()->all_symbols_read(workqueue,
this,
this->input_objects_,
this->symtab_,
this->dirpath_,
this->mapfile_,
&this->this_blocker_);
workqueue->queue_soon(new Plugin_finish(this->this_blocker_,
this->next_blocker_));
}
// The C interface routines called by the plugins.
#ifdef ENABLE_PLUGINS
// Register a claim-file handler.
static enum ld_plugin_status
register_claim_file(ld_plugin_claim_file_handler handler)
{
gold_assert(parameters->options().has_plugins());
parameters->options().plugins()->set_claim_file_handler(handler);
return LDPS_OK;
}
// Register an all-symbols-read handler.
static enum ld_plugin_status
register_all_symbols_read(ld_plugin_all_symbols_read_handler handler)
{
gold_assert(parameters->options().has_plugins());
parameters->options().plugins()->set_all_symbols_read_handler(handler);
return LDPS_OK;
}
// Register a cleanup handler.
static enum ld_plugin_status
register_cleanup(ld_plugin_cleanup_handler handler)
{
gold_assert(parameters->options().has_plugins());
parameters->options().plugins()->set_cleanup_handler(handler);
return LDPS_OK;
}
// Add symbols from a plugin-claimed input file.
static enum ld_plugin_status
add_symbols(void* handle, int nsyms, const ld_plugin_symbol* syms)
{
gold_assert(parameters->options().has_plugins());
Pluginobj* obj = parameters->options().plugins()->make_plugin_object(
static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
if (obj == NULL)
return LDPS_ERR;
obj->store_incoming_symbols(nsyms, syms);
return LDPS_OK;
}
// Get the input file information with an open (possibly re-opened)
// file descriptor.
static enum ld_plugin_status
get_input_file(const void* handle, struct ld_plugin_input_file* file)
{
gold_assert(parameters->options().has_plugins());
unsigned int obj_index =
static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
return parameters->options().plugins()->get_input_file(obj_index, file);
}
// Release the input file.
static enum ld_plugin_status
release_input_file(const void* handle)
{
gold_assert(parameters->options().has_plugins());
unsigned int obj_index =
static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
return parameters->options().plugins()->release_input_file(obj_index);
}
static enum ld_plugin_status
get_view(const void *handle, const void **viewp)
{
gold_assert(parameters->options().has_plugins());
unsigned int obj_index =
static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle));
return parameters->options().plugins()->get_view(obj_index, viewp);
}
// Get the symbol resolution info for a plugin-claimed input file.
static enum ld_plugin_status
get_symbols(const void* handle, int nsyms, ld_plugin_symbol* syms)
{
gold_assert(parameters->options().has_plugins());
Object* obj = parameters->options().plugins()->object(
static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
if (obj == NULL)
return LDPS_ERR;
Pluginobj* plugin_obj = obj->pluginobj();
if (plugin_obj == NULL)
return LDPS_ERR;
return plugin_obj->get_symbol_resolution_info(nsyms, syms, 1);
}
// Version 2 of the above. The only difference is that this version
// is allowed to return the resolution code LDPR_PREVAILING_DEF_IRONLY_EXP.
static enum ld_plugin_status
get_symbols_v2(const void* handle, int nsyms, ld_plugin_symbol* syms)
{
gold_assert(parameters->options().has_plugins());
Object* obj = parameters->options().plugins()->object(
static_cast<unsigned int>(reinterpret_cast<intptr_t>(handle)));
if (obj == NULL)
return LDPS_ERR;
Pluginobj* plugin_obj = obj->pluginobj();
if (plugin_obj == NULL)
return LDPS_ERR;
return plugin_obj->get_symbol_resolution_info(nsyms, syms, 2);
}
// Add a new (real) input file generated by a plugin.
static enum ld_plugin_status
add_input_file(const char* pathname)
{
gold_assert(parameters->options().has_plugins());
return parameters->options().plugins()->add_input_file(pathname, false);
}
// Add a new (real) library required by a plugin.
static enum ld_plugin_status
add_input_library(const char* pathname)
{
gold_assert(parameters->options().has_plugins());
return parameters->options().plugins()->add_input_file(pathname, true);
}
// Set the extra library path to be used by libraries added via
// add_input_library
static enum ld_plugin_status
set_extra_library_path(const char* path)
{
gold_assert(parameters->options().has_plugins());
return parameters->options().plugins()->set_extra_library_path(path);
}
// Issue a diagnostic message from a plugin.
static enum ld_plugin_status
message(int level, const char* format, ...)
{
va_list args;
va_start(args, format);
switch (level)
{
case LDPL_INFO:
parameters->errors()->info(format, args);
break;
case LDPL_WARNING:
parameters->errors()->warning(format, args);
break;
case LDPL_ERROR:
default:
parameters->errors()->error(format, args);
break;
case LDPL_FATAL:
parameters->errors()->fatal(format, args);
break;
}
va_end(args);
return LDPS_OK;
}
// Get the section count of the object corresponding to the handle. This
// plugin interface can only be called in the claim_file handler of the plugin.
static enum ld_plugin_status
get_input_section_count(const void* handle, unsigned int* count)
{
gold_assert(parameters->options().has_plugins());
if (!parameters->options().plugins()->in_claim_file_handler())
return LDPS_ERR;
Object* obj = parameters->options().plugins()->get_elf_object(handle);
if (obj == NULL)
return LDPS_ERR;
*count = obj->shnum();
return LDPS_OK;
}
// Get the type of the specified section in the object corresponding
// to the handle. This plugin interface can only be called in the
// claim_file handler of the plugin.
static enum ld_plugin_status
get_input_section_type(const struct ld_plugin_section section,
unsigned int* type)
{
gold_assert(parameters->options().has_plugins());
if (!parameters->options().plugins()->in_claim_file_handler())
return LDPS_ERR;
Object* obj
= parameters->options().plugins()->get_elf_object(section.handle);
if (obj == NULL)
return LDPS_BAD_HANDLE;
*type = obj->section_type(section.shndx);
return LDPS_OK;
}
// Get the name of the specified section in the object corresponding
// to the handle. This plugin interface can only be called in the
// claim_file handler of the plugin.
static enum ld_plugin_status
get_input_section_name(const struct ld_plugin_section section,
char** section_name_ptr)
{
gold_assert(parameters->options().has_plugins());
if (!parameters->options().plugins()->in_claim_file_handler())
return LDPS_ERR;
Object* obj
= parameters->options().plugins()->get_elf_object(section.handle);
if (obj == NULL)
return LDPS_BAD_HANDLE;
// Check if the object is locked before getting the section name.
gold_assert(obj->is_locked());
const std::string section_name = obj->section_name(section.shndx);
*section_name_ptr = static_cast<char*>(malloc(section_name.length() + 1));
memcpy(*section_name_ptr, section_name.c_str(), section_name.length() + 1);
return LDPS_OK;
}
// Get the contents of the specified section in the object corresponding
// to the handle. This plugin interface can only be called in the
// claim_file handler of the plugin.
static enum ld_plugin_status
get_input_section_contents(const struct ld_plugin_section section,
const unsigned char** section_contents_ptr,
size_t* len)
{
gold_assert(parameters->options().has_plugins());
if (!parameters->options().plugins()->in_claim_file_handler())
return LDPS_ERR;
Object* obj
= parameters->options().plugins()->get_elf_object(section.handle);
if (obj == NULL)
return LDPS_BAD_HANDLE;
// Check if the object is locked before getting the section contents.
gold_assert(obj->is_locked());
section_size_type plen;
*section_contents_ptr
= obj->section_contents(section.shndx, &plen, false);
*len = plen;
return LDPS_OK;
}
// Specify the ordering of sections in the final layout. The sections are
// specified as (handle,shndx) pairs in the two arrays in the order in
// which they should appear in the final layout.
static enum ld_plugin_status
update_section_order(const struct ld_plugin_section* section_list,
unsigned int num_sections)
{
gold_assert(parameters->options().has_plugins());
if (num_sections == 0)
return LDPS_OK;
if (section_list == NULL)
return LDPS_ERR;
Layout* layout = parameters->options().plugins()->layout();
gold_assert (layout != NULL);
std::map<Section_id, unsigned int>* order_map
= layout->get_section_order_map();
/* Store the mapping from Section_id to section position in layout's
order_map to consult after output sections are added. */
for (unsigned int i = 0; i < num_sections; ++i)
{
Object* obj = parameters->options().plugins()->get_elf_object(
section_list[i].handle);
if (obj == NULL)
return LDPS_BAD_HANDLE;
unsigned int shndx = section_list[i].shndx;
Section_id secn_id(obj, shndx);
(*order_map)[secn_id] = i + 1;
}
return LDPS_OK;
}
// Let the linker know that the sections could be reordered.
static enum ld_plugin_status
allow_section_ordering()
{
gold_assert(parameters->options().has_plugins());
Layout* layout = parameters->options().plugins()->layout();
layout->set_section_ordering_specified();
return LDPS_OK;
}
#endif // ENABLE_PLUGINS
// Allocate a Pluginobj object of the appropriate size and endianness.
static Pluginobj*
make_sized_plugin_object(Input_file* input_file, off_t offset, off_t filesize)
{
Pluginobj* obj = NULL;
parameters_force_valid_target();
const Target& target(parameters->target());
if (target.get_size() == 32)
{
if (target.is_big_endian())
#ifdef HAVE_TARGET_32_BIG
obj = new Sized_pluginobj<32, true>(input_file->filename(),
input_file, offset, filesize);
#else
gold_error(_("%s: not configured to support "
"32-bit big-endian object"),
input_file->filename().c_str());
#endif
else
#ifdef HAVE_TARGET_32_LITTLE
obj = new Sized_pluginobj<32, false>(input_file->filename(),
input_file, offset, filesize);
#else
gold_error(_("%s: not configured to support "
"32-bit little-endian object"),
input_file->filename().c_str());
#endif
}
else if (target.get_size() == 64)
{
if (target.is_big_endian())
#ifdef HAVE_TARGET_64_BIG
obj = new Sized_pluginobj<64, true>(input_file->filename(),
input_file, offset, filesize);
#else
gold_error(_("%s: not configured to support "
"64-bit big-endian object"),
input_file->filename().c_str());
#endif
else
#ifdef HAVE_TARGET_64_LITTLE
obj = new Sized_pluginobj<64, false>(input_file->filename(),
input_file, offset, filesize);
#else
gold_error(_("%s: not configured to support "
"64-bit little-endian object"),
input_file->filename().c_str());
#endif
}
gold_assert(obj != NULL);
return obj;
}
} // End namespace gold.
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