// Copyright (C) 2008-2024 Free Software Foundation, Inc.

// plugin.cc -- plugin manager for gold -*- C++ -*-

// Copyright (C) 2008-2024 Free Software Foundation, Inc.
// Written by Cary Coutant <[email protected]>.

// 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 <cerrno>
#include <cstdio>
#include <cstdarg>
#include <cstring>
#include <string>
#include <vector>
#include <fcntl.h>
#include <unistd.h>
#include "libiberty.h"

#ifdef ENABLE_PLUGINS
#ifdef HAVE_DLFCN_H
#include <dlfcn.h>
#elif defined (HAVE_WINDOWS_H)
#include <windows.h>
#else
#error Unknown how to handle dynamic-load-libraries.
#endif

#if !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H)

#define RTLD_NOW 0 /* Dummy value. */
static void *
dlopen(const char *file, int mode ATTRIBUTE_UNUSED)
{
return LoadLibrary(file);
}

static void *
dlsym(void *handle, const char *name)
{
return reinterpret_cast<void *>(
GetProcAddress(static_cast<HMODULE>(handle),name));
}

static const char *
dlerror(void)
{
return "unable to load dll";
}

#endif /* !defined (HAVE_DLFCN_H) && defined (HAVE_WINDOWS_H) */
#endif /* ENABLE_PLUGINS */

#include "parameters.h"
#include "debug.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 "descriptors.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
get_symbols_v3(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();

static enum ld_plugin_status
allow_unique_segment_for_sections();

static enum ld_plugin_status
unique_segment_for_sections(const char* segment_name,
uint64_t flags,
uint64_t align,
const struct ld_plugin_section *section_list,
unsigned int num_sections);

static enum ld_plugin_status
get_input_section_alignment(const struct ld_plugin_section section,
unsigned int* addralign);

static enum ld_plugin_status
get_input_section_size(const struct ld_plugin_section section,
uint64_t* secsize);

static enum ld_plugin_status
register_new_input(ld_plugin_new_input_handler handler);

static enum ld_plugin_status
get_wrap_symbols(uint64_t *num_symbols, const char ***wrap_symbol_list);

};

#endif // ENABLE_PLUGINS

static Pluginobj* make_sized_plugin_object(const std::string& filename,
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 = 31;

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 if (parameters->options().pie())
tv[i].tv_u.tv_val = LDPO_PIE;
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_GET_SYMBOLS_V3;
tv[i].tv_u.tv_get_symbols = get_symbols_v3;

++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_ALLOW_UNIQUE_SEGMENT_FOR_SECTIONS;
tv[i].tv_u.tv_allow_unique_segment_for_sections
= allow_unique_segment_for_sections;

++i;
tv[i].tv_tag = LDPT_UNIQUE_SEGMENT_FOR_SECTIONS;
tv[i].tv_u.tv_unique_segment_for_sections = unique_segment_for_sections;

++i;
tv[i].tv_tag = LDPT_GET_INPUT_SECTION_ALIGNMENT;
tv[i].tv_u.tv_get_input_section_alignment = get_input_section_alignment;

++i;
tv[i].tv_tag = LDPT_GET_INPUT_SECTION_SIZE;
tv[i].tv_u.tv_get_input_section_size = get_input_section_size;

++i;
tv[i].tv_tag = LDPT_REGISTER_NEW_INPUT_HOOK;
tv[i].tv_u.tv_register_new_input = register_new_input;

++i;
tv[i].tv_tag = LDPT_GET_WRAP_SYMBOLS;
tv[i].tv_u.tv_get_wrap_symbols = get_wrap_symbols;

++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 new_input handler.

inline void
Plugin::new_input(struct ld_plugin_input_file* plugin_input_file)
{
if (this->new_input_handler_ != NULL)
(*this->new_input_handler_)(plugin_input_file);
}

// 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_recorder logs plugin actions and saves intermediate files
// for later replay.

class Plugin_recorder
{
public:
Plugin_recorder() : file_count_(0), tempdir_(NULL), logfile_(NULL)
{ }

bool
init();

void
claimed_file(const std::string& obj_name, off_t offset, off_t filesize,
const std::string& plugin_name);

void
unclaimed_file(const std::string& obj_name, off_t offset, off_t filesize);

void
replacement_file(const char* name, bool is_lib);

void
record_symbols(const Object* obj, int nsyms,
const struct ld_plugin_symbol* syms);

void
finish()
{ ::fclose(this->logfile_); }

private:
unsigned int file_count_;
const char* tempdir_;
FILE* logfile_;
};

bool
Plugin_recorder::init()
{
// Create a temporary directory where we can stash the log and
// copies of replacement files.
char dir_template[] = "gold-recording-XXXXXX";
#ifdef HAVE_MKDTEMP
if (mkdtemp(dir_template) == NULL)
return false;
#else
if (mktemp(dir_template) == NULL)
return false;
#if defined (_WIN32) && !defined (__CYGWIN32__)
if (mkdir(dir_template) != 0)
return false;
#else
if (mkdir(dir_template, 0700) != 0)
return false;
#endif
#endif

size_t len = strlen(dir_template) + 1;
char* tempdir = new char[len];
memcpy(tempdir, dir_template, len);

// Create the log file.
std::string logname(tempdir);
logname.append("/log");
FILE* logfile = ::fopen(logname.c_str(), "w");
if (logfile == NULL)
return false;

this->tempdir_ = tempdir;
this->logfile_ = logfile;

gold_info(_("%s: recording to %s"), program_name, this->tempdir_);

return true;
}

void
Plugin_recorder::claimed_file(const std::string& obj_name,
off_t offset,
off_t filesize,
const std::string& plugin_name)
{
fprintf(this->logfile_, "PLUGIN: %s\n", plugin_name.c_str());
fprintf(this->logfile_, "CLAIMED: %s", obj_name.c_str());
if (offset > 0)
fprintf(this->logfile_, " @%ld", static_cast<long>(offset));
fprintf(this->logfile_, " %ld\n", static_cast<long>(filesize));
}

void
Plugin_recorder::unclaimed_file(const std::string& obj_name,
off_t offset,
off_t filesize)
{
fprintf(this->logfile_, "UNCLAIMED: %s", obj_name.c_str());
if (offset > 0)
fprintf(this->logfile_, " @%ld", static_cast<long>(offset));
fprintf(this->logfile_, " %ld\n", static_cast<long>(filesize));
}

// Make a hard link to INNAME from OUTNAME, if possible.
// If not, copy the file.

static bool
link_or_copy_file(const char* inname, const char* outname)
{
static char buf[4096];

#ifdef HAVE_LINK
if (::link(inname, outname) == 0)
return true;
#endif

int in = ::open(inname, O_RDONLY);
if (in < 0)
{
gold_warning(_("%s: can't open (%s)"), inname, strerror(errno));
return false;
}
int out = ::open(outname, O_CREAT | O_TRUNC | O_WRONLY, 0600);
if (out < 0)
{
gold_warning(_("%s: can't create (%s)"), outname, strerror(errno));
::close(in);
return false;
}
ssize_t len;
while ((len = ::read(in, buf, sizeof(buf))) > 0)
{
if (::write(out, buf, len) != len)
{
gold_warning(_("%s: write error while making copy of file (%s)"),
inname, strerror(errno));
break;
}
}
::close(in);
::close(out);
return true;
}

void
Plugin_recorder::replacement_file(const char* name, bool is_lib)
{
fprintf(this->logfile_, "REPLACEMENT: %s", name);
if (is_lib)
fprintf(this->logfile_, "(lib)");
else
{
char counter[10];
const char* basename = lbasename(name);
snprintf(counter, sizeof(counter), "%05d", this->file_count_);
++this->file_count_;
std::string outname(this->tempdir_);
outname.append("/");
outname.append(counter);
outname.append("-");
outname.append(basename);
if (link_or_copy_file(name, outname.c_str()))
fprintf(this->logfile_, " -> %s", outname.c_str());
}
fprintf(this->logfile_, "\n");
}

void
Plugin_recorder::record_symbols(const Object* obj, int nsyms,
const struct ld_plugin_symbol* syms)
{
fprintf(this->logfile_, "SYMBOLS: %d %s\n", nsyms, obj->name().c_str());
for (int i = 0; i < nsyms; ++i)
{
const struct ld_plugin_symbol* isym = &syms[i];

const char* def;
switch (isym->def)
{
case LDPK_DEF:
def = "D";
break;
case LDPK_WEAKDEF:
def = "WD";
break;
case LDPK_UNDEF:
def = "U";
break;
case LDPK_WEAKUNDEF:
def = "WU";
break;
case LDPK_COMMON:
def = "C";
break;
default:
def = "?";
break;
}

char vis;
switch (isym->visibility)
{
case LDPV_PROTECTED:
vis = 'P';
break;
case LDPV_INTERNAL:
vis = 'I';
break;
case LDPV_HIDDEN:
vis = 'H';
break;
case LDPV_DEFAULT:
vis = 'D';
break;
default:
vis = '?';
break;
}

fprintf(this->logfile_, " %5d: %-2s %c %s", i, def, vis, isym->name);
if (isym->version != NULL && isym->version[0] != '\0')
fprintf(this->logfile_, "@%s", isym->version);
if (isym->comdat_key != NULL && isym->comdat_key[0] != '\0')
{
if (strcmp(isym->name, isym->comdat_key) == 0)
fprintf(this->logfile_, " [comdat]");
else
fprintf(this->logfile_, " [comdat: %s]", isym->comdat_key);
}
fprintf(this->logfile_, "\n");
}
}

// 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();
delete this->lock_;
delete this->recorder_;
}

// Load all plugin libraries.

void
Plugin_manager::load_plugins(Layout* layout)
{
this->layout_ = layout;

if (is_debugging_enabled(DEBUG_PLUGIN))
{
this->recorder_ = new Plugin_recorder();
this->recorder_->init();
}

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)
{
bool lock_initialized = this->initialize_lock_.initialize();

gold_assert(lock_initialized);
Hold_lock hl(*this->lock_);

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 (Plugin_list::iterator p = this->plugins_.begin();
p != this->plugins_.end();
++p)
{
// If we aren't yet in replacement phase, allow plugins to claim input
// files, otherwise notify the plugin of the new input file, if needed.
if (!this->in_replacement_phase_)
{
if ((*p)->claim_file(&this->plugin_input_file_))
{
this->any_claimed_ = true;
this->in_claim_file_handler_ = false;

if (this->recorder_ != NULL)
{
const std::string& objname = (elf_object == NULL
? input_file->filename()
: elf_object->name());
this->recorder_->claimed_file(objname,
offset, filesize,
(*p)->filename());
}

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;
}
}
else
{
(*p)->new_input(&this->plugin_input_file_);
}
}

this->in_claim_file_handler_ = false;

if (this->recorder_ != NULL)
this->recorder_->unclaimed_file(input_file->filename(), offset, filesize);

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;

// Set symbols used in defsym expressions as seen in real ELF.
Layout *layout = parameters->options().plugins()->layout();
layout->script_options()->set_defsym_uses_in_real_elf(symtab);
layout->script_options()->find_defsym_defs(this->defsym_defines_set_);

for (Plugin_list::iterator p = this->plugins_.begin();
p != this->plugins_.end();
++p)
(*p)->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()
{
if (this->any_added_)
{
// If any input files were added, close all the input files.
// This is because the plugin may want to remove them, and on
// Windows you are not allowed to remove an open file.
close_all_descriptors();
}

for (Plugin_list::iterator p = this->plugins_.begin();
p != this->plugins_.end();
++p)
(*p)->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;

const std::string* filename = &this->input_file_->filename();

// If the elf object for this file was pushed into the objects_ vector,
// use its filename, then delete it to make room for the Pluginobj as
// this file is claimed.
if (this->objects_.size() != handle)
{
filename = &this->objects_.back()->name();
this->objects_.pop_back();
}

Pluginobj* obj = make_sized_plugin_object(*filename,
this->input_file_,
this->plugin_input_file_.offset,
this->plugin_input_file_.filesize);

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"));

if (this->recorder_ != NULL)
this->recorder_->replacement_file(pathname, is_lib);

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. Only references from relocatable,
// non-IR (unclaimed) objects count as a reference. References from
// dynamic objects count only as "visible".

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 (lsym->in_dyn())
return true;
if (parameters->options().export_dynamic() || parameters->options().shared()
|| parameters->options().in_dynamic_list(lsym->name())
|| parameters->options().is_export_dynamic_symbol(lsym->name()))
return lsym->is_externally_visible();
return false;
}

// Get symbol resolution info.

ld_plugin_status
Pluginobj::get_symbol_resolution_info(Symbol_table* symtab,
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 version > 2 ? LDPS_NO_SYMS : LDPS_OK;
}

Plugin_manager* plugins = parameters->options().plugins();
for (int i = 0; i < nsyms; i++)
{
ld_plugin_symbol* isym = &syms[i];
Symbol* lsym = this->symbols_[i];
if (lsym->is_forwarder())
lsym = symtab->resolve_forwards(lsym);
ld_plugin_symbol_resolution res = LDPR_UNKNOWN;

if (plugins->is_defsym_def(lsym->name()))
{
// The symbol is redefined via defsym.
res = LDPR_PREEMPTED_REG;
}
else 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_write<size, big_endian> osym(symbuf);

Plugin_recorder* recorder = parameters->options().plugins()->recorder();
if (recorder != NULL)
recorder->record_symbols(this, this->nsyms_, this->syms_);

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:
// We use an arbitrary section number for a defined symbol.
shndx = 1;
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(0);
osym.put_st_info(bind, elfcpp::STT_NOTYPE);
osym.put_st_other(vis, 0);
osym.put_st_shndx(shndx);

elfcpp::Sym<size, big_endian> sym(symbuf);
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];
if (sym.def == LDPK_UNDEF || sym.def == LDPK_WEAKUNDEF)
continue;
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) const
{
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>
const unsigned char*
Sized_pluginobj<size, big_endian>::do_section_contents(
unsigned int,
section_size_type*,
bool)
{
gold_unreachable();
return NULL;
}

// 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. Don't count plugin objects; the replacement
// files will provide the counts.

template<int size, bool big_endian>
void
Sized_pluginobj<size, big_endian>::do_get_global_symbol_counts(
const Symbol_table*,
size_t* defined,
size_t* used) const
{
*defined = 0;
*used = 0;
}

// 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*)
{
Plugin_manager* plugins = parameters->options().plugins();
gold_assert(plugins != NULL);
// We could call early cleanup handlers here.
if (plugins->recorder())
plugins->recorder()->finish();
}

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());
Plugin_manager* plugins = parameters->options().plugins();
Object* obj = 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;
Symbol_table* symtab = plugins->symtab();
return plugin_obj->get_symbol_resolution_info(symtab, 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());
Plugin_manager* plugins = parameters->options().plugins();
Object* obj = 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;
Symbol_table* symtab = plugins->symtab();
return plugin_obj->get_symbol_resolution_info(symtab, nsyms, syms, 2);
}

// Version 3 of the above. The only difference from v2 is that it
// returns LDPS_NO_SYMS instead of LDPS_OK for the objects we never
// decided to include.

static enum ld_plugin_status
get_symbols_v3(const void* handle, int nsyms, ld_plugin_symbol* syms)
{
gold_assert(parameters->options().has_plugins());
Plugin_manager* plugins = parameters->options().plugins();
Object* obj = 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;
Symbol_table* symtab = plugins->symtab();
return plugin_obj->get_symbol_resolution_info(symtab, nsyms, syms, 3);
}

// 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;
}

// Get the alignment 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_alignment(const struct ld_plugin_section section,
unsigned int* addralign)
{
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;

*addralign = obj->section_addralign(section.shndx);
return LDPS_OK;
}

// Get the size 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_size(const struct ld_plugin_section section,
uint64_t* secsize)
{
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;

*secsize = obj->section_size(section.shndx);
return LDPS_OK;
}

static enum ld_plugin_status
get_wrap_symbols(uint64_t *count, const char ***wrap_symbols)
{
gold_assert(parameters->options().has_plugins());
*count = parameters->options().wrap_size();

if (*count == 0)
return LDPS_OK;

*wrap_symbols = new const char *[*count];
int i = 0;
for (options::String_set::const_iterator
it = parameters->options().wrap_begin();
it != parameters->options().wrap_end(); ++it, ++i) {
(*wrap_symbols)[i] = it->c_str();
}
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 || obj->is_dynamic())
return LDPS_BAD_HANDLE;
unsigned int shndx = section_list[i].shndx;
Section_id secn_id(static_cast<Relobj*>(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;
}

// Let the linker know that a subset of sections could be mapped
// to a unique segment.

static enum ld_plugin_status
allow_unique_segment_for_sections()
{
gold_assert(parameters->options().has_plugins());
Layout* layout = parameters->options().plugins()->layout();
layout->set_unique_segment_for_sections_specified();
return LDPS_OK;
}

// This function should map the list of sections specified in the
// SECTION_LIST to a unique segment. ELF segments do not have names
// and the NAME is used to identify Output Section which should contain
// the list of sections. This Output Section will then be mapped to
// a unique segment. FLAGS is used to specify if any additional segment
// flags need to be set. For instance, a specific segment flag can be
// set to identify this segment. Unsetting segment flags is not possible.
// ALIGN specifies the alignment of the segment.

static enum ld_plugin_status
unique_segment_for_sections(const char* segment_name,
uint64_t flags,
uint64_t align,
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);

Layout::Unique_segment_info* s = new Layout::Unique_segment_info;
s->name = segment_name;
s->flags = flags;
s->align = align;

for (unsigned int i = 0; i < num_sections; ++i)
{
Object* obj = parameters->options().plugins()->get_elf_object(
section_list[i].handle);
if (obj == NULL || obj->is_dynamic())
return LDPS_BAD_HANDLE;
unsigned int shndx = section_list[i].shndx;
Const_section_id secn_id(static_cast<Relobj*>(obj), shndx);
layout->insert_section_segment_map(secn_id, s);
}

return LDPS_OK;
}

// Register a new_input handler.

static enum ld_plugin_status
register_new_input(ld_plugin_new_input_handler handler)
{
gold_assert(parameters->options().has_plugins());
parameters->options().plugins()->set_new_input_handler(handler);
return LDPS_OK;
}

#endif // ENABLE_PLUGINS

// Allocate a Pluginobj object of the appropriate size and endianness.

static Pluginobj*
make_sized_plugin_object(const std::string& filename,
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>(filename, input_file,
offset, filesize);
#else
gold_error(_("%s: not configured to support "
"32-bit big-endian object"),
filename.c_str());
#endif
else
#ifdef HAVE_TARGET_32_LITTLE
obj = new Sized_pluginobj<32, false>(filename, input_file,
offset, filesize);
#else
gold_error(_("%s: not configured to support "
"32-bit little-endian object"),
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>(filename, input_file,
offset, filesize);
#else
gold_error(_("%s: not configured to support "
"64-bit big-endian object"),
filename.c_str());
#endif
else
#ifdef HAVE_TARGET_64_LITTLE
obj = new Sized_pluginobj<64, false>(filename, input_file,
offset, filesize);
#else
gold_error(_("%s: not configured to support "
"64-bit little-endian object"),
filename.c_str());
#endif
}

gold_assert(obj != NULL);
return obj;
}

} // End namespace gold.