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|
// archive.cc -- archive support for gold
// Copyright (C) 2006-2015 Free Software Foundation, Inc.
// Written by Ian Lance Taylor <iant@google.com>.
// This file is part of gold.
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
// MA 02110-1301, USA.
#include "gold.h"
#include <cerrno>
#include <cstring>
#include <climits>
#include <vector>
#include "libiberty.h"
#include "filenames.h"
#include "elfcpp.h"
#include "options.h"
#include "mapfile.h"
#include "fileread.h"
#include "readsyms.h"
#include "symtab.h"
#include "object.h"
#include "layout.h"
#include "archive.h"
#include "plugin.h"
#include "incremental.h"
namespace gold
{
// Library_base methods.
// Determine whether a definition of SYM_NAME should cause an archive
// library member to be included in the link. Returns SHOULD_INCLUDE_YES
// if the symbol is referenced but not defined, SHOULD_INCLUDE_NO if the
// symbol is already defined, and SHOULD_INCLUDE_UNKNOWN if the symbol is
// neither referenced nor defined.
Library_base::Should_include
Library_base::should_include_member(Symbol_table* symtab, Layout* layout,
const char* sym_name, Symbol** symp,
std::string* why, char** tmpbufp,
size_t* tmpbuflen)
{
// In an object file, and therefore in an archive map, an
// '@' in the name separates the symbol name from the
// version name. If there are two '@' characters, this is
// the default version.
char* tmpbuf = *tmpbufp;
const char* ver = strchr(sym_name, '@');
bool def = false;
if (ver != NULL)
{
size_t symlen = ver - sym_name;
if (symlen + 1 > *tmpbuflen)
{
tmpbuf = static_cast<char*>(xrealloc(tmpbuf, symlen + 1));
*tmpbufp = tmpbuf;
*tmpbuflen = symlen + 1;
}
memcpy(tmpbuf, sym_name, symlen);
tmpbuf[symlen] = '\0';
sym_name = tmpbuf;
++ver;
if (*ver == '@')
{
++ver;
def = true;
}
}
Symbol* sym = symtab->lookup(sym_name, ver);
if (def
&& ver != NULL
&& (sym == NULL
|| !sym->is_undefined()
|| sym->binding() == elfcpp::STB_WEAK))
sym = symtab->lookup(sym_name, NULL);
*symp = sym;
if (sym != NULL)
{
if (!sym->is_undefined())
return Library_base::SHOULD_INCLUDE_NO;
// PR 12001: Do not include an archive when the undefined
// symbol has actually been defined on the command line.
if (layout->script_options()->is_pending_assignment(sym_name))
return Library_base::SHOULD_INCLUDE_NO;
// If the symbol is weak undefined, we still need to check
// for other reasons (like a -u option).
if (sym->binding() != elfcpp::STB_WEAK)
return Library_base::SHOULD_INCLUDE_YES;
}
// Check whether the symbol was named in a -u option.
if (parameters->options().is_undefined(sym_name))
{
*why = "-u ";
*why += sym_name;
return Library_base::SHOULD_INCLUDE_YES;
}
if (parameters->options().is_export_dynamic_symbol(sym_name))
{
*why = "--export-dynamic-symbol ";
*why += sym_name;
return Library_base::SHOULD_INCLUDE_YES;
}
if (layout->script_options()->is_referenced(sym_name))
{
size_t alc = 100 + strlen(sym_name);
char* buf = new char[alc];
snprintf(buf, alc, _("script or expression reference to %s"),
sym_name);
*why = buf;
delete[] buf;
return Library_base::SHOULD_INCLUDE_YES;
}
if (strcmp(sym_name, parameters->entry()) == 0)
{
*why = "entry symbol ";
*why += sym_name;
return Library_base::SHOULD_INCLUDE_YES;
}
return Library_base::SHOULD_INCLUDE_UNKNOWN;
}
// The header of an entry in the archive. This is all readable text,
// padded with spaces where necessary. If the contents of an archive
// are all text file, the entire archive is readable.
struct Archive::Archive_header
{
// The entry name.
char ar_name[16];
// The file modification time.
char ar_date[12];
// The user's UID in decimal.
char ar_uid[6];
// The user's GID in decimal.
char ar_gid[6];
// The file mode in octal.
char ar_mode[8];
// The file size in decimal.
char ar_size[10];
// The final magic code.
char ar_fmag[2];
};
// Class Archive static variables.
unsigned int Archive::total_archives;
unsigned int Archive::total_members;
unsigned int Archive::total_members_loaded;
// Archive methods.
const char Archive::armag[sarmag] =
{
'!', '<', 'a', 'r', 'c', 'h', '>', '\n'
};
const char Archive::armagt[sarmag] =
{
'!', '<', 't', 'h', 'i', 'n', '>', '\n'
};
const char Archive::arfmag[2] = { '`', '\n' };
Archive::Archive(const std::string& name, Input_file* input_file,
bool is_thin_archive, Dirsearch* dirpath, Task* task)
: Library_base(task), name_(name), input_file_(input_file), armap_(),
armap_names_(), extended_names_(), armap_checked_(), seen_offsets_(),
members_(), is_thin_archive_(is_thin_archive), included_member_(false),
nested_archives_(), dirpath_(dirpath), num_members_(0),
included_all_members_(false)
{
this->no_export_ =
parameters->options().check_excluded_libs(input_file->found_name());
}
// Set up the archive: read the symbol map and the extended name
// table.
void
Archive::setup()
{
// We need to ignore empty archives.
if (this->input_file_->file().filesize() == sarmag)
return;
// The first member of the archive should be the symbol table.
std::string armap_name;
off_t header_size = this->read_header(sarmag, false, &armap_name, NULL);
if (header_size == -1)
return;
section_size_type armap_size = convert_to_section_size_type(header_size);
off_t off = sarmag;
if (armap_name.empty())
{
this->read_armap(sarmag + sizeof(Archive_header), armap_size);
off = sarmag + sizeof(Archive_header) + armap_size;
}
else if (!this->input_file_->options().whole_archive())
gold_error(_("%s: no archive symbol table (run ranlib)"),
this->name().c_str());
// See if there is an extended name table. We cache these views
// because it is likely that we will want to read the following
// header in the add_symbols routine.
if ((off & 1) != 0)
++off;
std::string xname;
header_size = this->read_header(off, true, &xname, NULL);
if (header_size == -1)
return;
section_size_type extended_size = convert_to_section_size_type(header_size);
if (xname == "/")
{
const unsigned char* p = this->get_view(off + sizeof(Archive_header),
extended_size, false, true);
const char* px = reinterpret_cast<const char*>(p);
this->extended_names_.assign(px, extended_size);
}
bool preread_syms = (parameters->options().threads()
&& parameters->options().preread_archive_symbols());
#ifndef ENABLE_THREADS
preread_syms = false;
#else
if (parameters->options().has_plugins())
preread_syms = false;
#endif
if (preread_syms)
this->read_all_symbols();
}
// Unlock any nested archives.
void
Archive::unlock_nested_archives()
{
for (Nested_archive_table::iterator p = this->nested_archives_.begin();
p != this->nested_archives_.end();
++p)
{
p->second->unlock(this->task_);
}
}
// Read the archive symbol map.
void
Archive::read_armap(off_t start, section_size_type size)
{
// To count the total number of archive members, we'll just count
// the number of times the file offset changes. Since most archives
// group the symbols in the armap by object, this ought to give us
// an accurate count.
off_t last_seen_offset = -1;
// Read in the entire armap.
const unsigned char* p = this->get_view(start, size, true, false);
// Numbers in the armap are always big-endian.
const elfcpp::Elf_Word* pword = reinterpret_cast<const elfcpp::Elf_Word*>(p);
unsigned int nsyms = elfcpp::Swap<32, true>::readval(pword);
++pword;
// Note that the addition is in units of sizeof(elfcpp::Elf_Word).
const char* pnames = reinterpret_cast<const char*>(pword + nsyms);
section_size_type names_size =
reinterpret_cast<const char*>(p) + size - pnames;
this->armap_names_.assign(pnames, names_size);
this->armap_.resize(nsyms);
section_offset_type name_offset = 0;
for (unsigned int i = 0; i < nsyms; ++i)
{
this->armap_[i].name_offset = name_offset;
this->armap_[i].file_offset = elfcpp::Swap<32, true>::readval(pword);
name_offset += strlen(pnames + name_offset) + 1;
++pword;
if (this->armap_[i].file_offset != last_seen_offset)
{
last_seen_offset = this->armap_[i].file_offset;
++this->num_members_;
}
}
if (static_cast<section_size_type>(name_offset) > names_size)
gold_error(_("%s: bad archive symbol table names"),
this->name().c_str());
// This array keeps track of which symbols are for archive elements
// which we have already included in the link.
this->armap_checked_.resize(nsyms);
}
// Read the header of an archive member at OFF. Fail if something
// goes wrong. Return the size of the member. Set *PNAME to the name
// of the member.
off_t
Archive::read_header(off_t off, bool cache, std::string* pname,
off_t* nested_off)
{
const unsigned char* p = this->get_view(off, sizeof(Archive_header), true,
cache);
const Archive_header* hdr = reinterpret_cast<const Archive_header*>(p);
return this->interpret_header(hdr, off, pname, nested_off);
}
// Interpret the header of HDR, the header of the archive member at
// file offset OFF. Return the size of the member, or -1 if something
// has gone wrong. Set *PNAME to the name of the member.
off_t
Archive::interpret_header(const Archive_header* hdr, off_t off,
std::string* pname, off_t* nested_off) const
{
if (memcmp(hdr->ar_fmag, arfmag, sizeof arfmag) != 0)
{
gold_error(_("%s: malformed archive header at %zu"),
this->name().c_str(), static_cast<size_t>(off));
return -1;
}
const int size_string_size = sizeof hdr->ar_size;
char size_string[size_string_size + 1];
memcpy(size_string, hdr->ar_size, size_string_size);
char* ps = size_string + size_string_size;
while (ps[-1] == ' ')
--ps;
*ps = '\0';
errno = 0;
char* end;
off_t member_size = strtol(size_string, &end, 10);
if (*end != '\0'
|| member_size < 0
|| (member_size == LONG_MAX && errno == ERANGE))
{
gold_error(_("%s: malformed archive header size at %zu"),
this->name().c_str(), static_cast<size_t>(off));
return -1;
}
if (hdr->ar_name[0] != '/')
{
const char* name_end = strchr(hdr->ar_name, '/');
if (name_end == NULL
|| name_end - hdr->ar_name >= static_cast<int>(sizeof hdr->ar_name))
{
gold_error(_("%s: malformed archive header name at %zu"),
this->name().c_str(), static_cast<size_t>(off));
return -1;
}
pname->assign(hdr->ar_name, name_end - hdr->ar_name);
if (nested_off != NULL)
*nested_off = 0;
}
else if (hdr->ar_name[1] == ' ')
{
// This is the symbol table.
if (!pname->empty())
pname->clear();
}
else if (hdr->ar_name[1] == '/')
{
// This is the extended name table.
pname->assign(1, '/');
}
else
{
errno = 0;
long x = strtol(hdr->ar_name + 1, &end, 10);
long y = 0;
if (*end == ':')
y = strtol(end + 1, &end, 10);
if (*end != ' '
|| x < 0
|| (x == LONG_MAX && errno == ERANGE)
|| static_cast<size_t>(x) >= this->extended_names_.size())
{
gold_error(_("%s: bad extended name index at %zu"),
this->name().c_str(), static_cast<size_t>(off));
return -1;
}
const char* name = this->extended_names_.data() + x;
const char* name_end = strchr(name, '\n');
if (static_cast<size_t>(name_end - name) > this->extended_names_.size()
|| name_end[-1] != '/')
{
gold_error(_("%s: bad extended name entry at header %zu"),
this->name().c_str(), static_cast<size_t>(off));
return -1;
}
pname->assign(name, name_end - 1 - name);
if (nested_off != NULL)
*nested_off = y;
}
return member_size;
}
// An archive member iterator.
class Archive::const_iterator
{
public:
// The header of an archive member. This is what this iterator
// points to.
struct Header
{
// The name of the member.
std::string name;
// The file offset of the member.
off_t off;
// The file offset of a nested archive member.
off_t nested_off;
// The size of the member.
off_t size;
};
const_iterator(Archive* archive, off_t off)
: archive_(archive), off_(off)
{ this->read_next_header(); }
const Header&
operator*() const
{ return this->header_; }
const Header*
operator->() const
{ return &this->header_; }
const_iterator&
operator++()
{
if (this->off_ == this->archive_->file().filesize())
return *this;
this->off_ += sizeof(Archive_header);
if (!this->archive_->is_thin_archive())
this->off_ += this->header_.size;
if ((this->off_ & 1) != 0)
++this->off_;
this->read_next_header();
return *this;
}
const_iterator
operator++(int)
{
const_iterator ret = *this;
++*this;
return ret;
}
bool
operator==(const const_iterator p) const
{ return this->off_ == p->off; }
bool
operator!=(const const_iterator p) const
{ return this->off_ != p->off; }
private:
void
read_next_header();
// The underlying archive.
Archive* archive_;
// The current offset in the file.
off_t off_;
// The current archive header.
Header header_;
};
// Read the next archive header.
void
Archive::const_iterator::read_next_header()
{
off_t filesize = this->archive_->file().filesize();
while (true)
{
if (filesize - this->off_ < static_cast<off_t>(sizeof(Archive_header)))
{
if (filesize != this->off_)
{
gold_error(_("%s: short archive header at %zu"),
this->archive_->filename().c_str(),
static_cast<size_t>(this->off_));
this->off_ = filesize;
}
this->header_.off = filesize;
return;
}
unsigned char buf[sizeof(Archive_header)];
this->archive_->file().read(this->off_, sizeof(Archive_header), buf);
const Archive_header* hdr = reinterpret_cast<const Archive_header*>(buf);
off_t size = this->archive_->interpret_header(hdr, this->off_,
&this->header_.name,
&this->header_.nested_off);
if (size == -1)
{
this->header_.off = filesize;
return;
}
this->header_.size = size;
this->header_.off = this->off_;
// Skip special members.
if (!this->header_.name.empty() && this->header_.name != "/")
return;
this->off_ += sizeof(Archive_header) + this->header_.size;
if ((this->off_ & 1) != 0)
++this->off_;
}
}
// Initial iterator.
Archive::const_iterator
Archive::begin()
{
return Archive::const_iterator(this, sarmag);
}
// Final iterator.
Archive::const_iterator
Archive::end()
{
return Archive::const_iterator(this, this->input_file_->file().filesize());
}
// Get the file and offset for an archive member, which may be an
// external member of a thin archive. Set *INPUT_FILE to the
// file containing the actual member, *MEMOFF to the offset
// within that file (0 if not a nested archive), and *MEMBER_NAME
// to the name of the archive member. Return TRUE on success.
bool
Archive::get_file_and_offset(off_t off, Input_file** input_file, off_t* memoff,
off_t* memsize, std::string* member_name)
{
off_t nested_off;
*memsize = this->read_header(off, false, member_name, &nested_off);
if (*memsize == -1)
return false;
*input_file = this->input_file_;
*memoff = off + static_cast<off_t>(sizeof(Archive_header));
if (!this->is_thin_archive_)
return true;
// Adjust a relative pathname so that it is relative
// to the directory containing the archive.
if (!IS_ABSOLUTE_PATH(member_name->c_str()))
{
const char* arch_path = this->filename().c_str();
const char* basename = lbasename(arch_path);
if (basename > arch_path)
member_name->replace(0, 0,
this->filename().substr(0, basename - arch_path));
}
if (nested_off > 0)
{
// This is a member of a nested archive. Open the containing
// archive if we don't already have it open, then do a recursive
// call to include the member from that archive.
Archive* arch;
Nested_archive_table::const_iterator p =
this->nested_archives_.find(*member_name);
if (p != this->nested_archives_.end())
arch = p->second;
else
{
Input_file_argument* input_file_arg =
new Input_file_argument(member_name->c_str(),
Input_file_argument::INPUT_FILE_TYPE_FILE,
"", false, parameters->options());
*input_file = new Input_file(input_file_arg);
int dummy = 0;
if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
return false;
arch = new Archive(*member_name, *input_file, false, this->dirpath_,
this->task_);
arch->setup();
std::pair<Nested_archive_table::iterator, bool> ins =
this->nested_archives_.insert(std::make_pair(*member_name, arch));
gold_assert(ins.second);
}
return arch->get_file_and_offset(nested_off, input_file, memoff,
memsize, member_name);
}
// This is an external member of a thin archive. Open the
// file as a regular relocatable object file.
Input_file_argument* input_file_arg =
new Input_file_argument(member_name->c_str(),
Input_file_argument::INPUT_FILE_TYPE_FILE,
"", false, this->input_file_->options());
*input_file = new Input_file(input_file_arg);
int dummy = 0;
if (!(*input_file)->open(*this->dirpath_, this->task_, &dummy))
return false;
*memoff = 0;
*memsize = (*input_file)->file().filesize();
return true;
}
// Return an ELF object for the member at offset OFF. If
// PUNCONFIGURED is not NULL, then if the ELF object has an
// unsupported target type, set *PUNCONFIGURED to true and return
// NULL.
Object*
Archive::get_elf_object_for_member(off_t off, bool* punconfigured)
{
if (punconfigured != NULL)
*punconfigured = false;
Input_file* input_file;
off_t memoff;
off_t memsize;
std::string member_name;
if (!this->get_file_and_offset(off, &input_file, &memoff, &memsize,
&member_name))
return NULL;
const unsigned char* ehdr;
int read_size;
Object *obj = NULL;
bool is_elf_obj = false;
if (is_elf_object(input_file, memoff, &ehdr, &read_size))
{
obj = make_elf_object((std::string(this->input_file_->filename())
+ "(" + member_name + ")"),
input_file, memoff, ehdr, read_size,
punconfigured);
is_elf_obj = true;
}
if (parameters->options().has_plugins())
{
Object* plugin_obj
= parameters->options().plugins()->claim_file(input_file,
memoff,
memsize,
obj);
if (plugin_obj != NULL)
{
// The input file was claimed by a plugin, and its symbols
// have been provided by the plugin.
// Delete its elf object.
if (obj != NULL)
delete obj;
return plugin_obj;
}
}
if (!is_elf_obj)
{
gold_error(_("%s: member at %zu is not an ELF object"),
this->name().c_str(), static_cast<size_t>(off));
return NULL;
}
if (obj == NULL)
return NULL;
obj->set_no_export(this->no_export());
return obj;
}
// Read the symbols from all the archive members in the link.
void
Archive::read_all_symbols()
{
for (Archive::const_iterator p = this->begin();
p != this->end();
++p)
this->read_symbols(p->off);
}
// Read the symbols from an archive member in the link. OFF is the file
// offset of the member header.
void
Archive::read_symbols(off_t off)
{
Object* obj = this->get_elf_object_for_member(off, NULL);
if (obj == NULL)
return;
Read_symbols_data* sd = new Read_symbols_data;
obj->read_symbols(sd);
Archive_member member(obj, sd);
this->members_[off] = member;
}
// Select members from the archive and add them to the link. We walk
// through the elements in the archive map, and look each one up in
// the symbol table. If it exists as a strong undefined symbol, we
// pull in the corresponding element. We have to do this in a loop,
// since pulling in one element may create new undefined symbols which
// may be satisfied by other objects in the archive. Return true in
// the normal case, false if the first member we tried to add from
// this archive had an incompatible target.
bool
Archive::add_symbols(Symbol_table* symtab, Layout* layout,
Input_objects* input_objects, Mapfile* mapfile)
{
++Archive::total_archives;
if (this->input_file_->options().whole_archive())
return this->include_all_members(symtab, layout, input_objects,
mapfile);
Archive::total_members += this->num_members_;
input_objects->archive_start(this);
const size_t armap_size = this->armap_.size();
// This is a quick optimization, since we usually see many symbols
// in a row with the same offset. last_seen_offset holds the last
// offset we saw that was present in the seen_offsets_ set.
off_t last_seen_offset = -1;
// Track which symbols in the symbol table we've already found to be
// defined.
char* tmpbuf = NULL;
size_t tmpbuflen = 0;
bool added_new_object;
do
{
added_new_object = false;
for (size_t i = 0; i < armap_size; ++i)
{
if (this->armap_checked_[i])
continue;
if (this->armap_[i].file_offset == last_seen_offset)
{
this->armap_checked_[i] = true;
continue;
}
if (this->seen_offsets_.find(this->armap_[i].file_offset)
!= this->seen_offsets_.end())
{
this->armap_checked_[i] = true;
last_seen_offset = this->armap_[i].file_offset;
continue;
}
const char* sym_name = (this->armap_names_.data()
+ this->armap_[i].name_offset);
Symbol* sym;
std::string why;
Archive::Should_include t =
Archive::should_include_member(symtab, layout, sym_name, &sym,
&why, &tmpbuf, &tmpbuflen);
if (t == Archive::SHOULD_INCLUDE_NO
|| t == Archive::SHOULD_INCLUDE_YES)
this->armap_checked_[i] = true;
if (t != Archive::SHOULD_INCLUDE_YES)
continue;
// We want to include this object in the link.
last_seen_offset = this->armap_[i].file_offset;
this->seen_offsets_.insert(last_seen_offset);
if (!this->include_member(symtab, layout, input_objects,
last_seen_offset, mapfile, sym,
why.c_str()))
{
if (tmpbuf != NULL)
free(tmpbuf);
return false;
}
added_new_object = true;
}
}
while (added_new_object);
if (tmpbuf != NULL)
free(tmpbuf);
input_objects->archive_stop(this);
return true;
}
// Return whether the archive includes a member which defines the
// symbol SYM.
bool
Archive::defines_symbol(Symbol* sym) const
{
const char* symname = sym->name();
size_t symname_len = strlen(symname);
size_t armap_size = this->armap_.size();
for (size_t i = 0; i < armap_size; ++i)
{
if (this->armap_checked_[i])
continue;
const char* archive_symname = (this->armap_names_.data()
+ this->armap_[i].name_offset);
if (strncmp(archive_symname, symname, symname_len) != 0)
continue;
char c = archive_symname[symname_len];
if (c == '\0' && sym->version() == NULL)
return true;
if (c == '@')
{
const char* ver = archive_symname + symname_len + 1;
if (*ver == '@')
{
if (sym->version() == NULL)
return true;
++ver;
}
if (sym->version() != NULL && strcmp(sym->version(), ver) == 0)
return true;
}
}
return false;
}
// Include all the archive members in the link. This is for --whole-archive.
bool
Archive::include_all_members(Symbol_table* symtab, Layout* layout,
Input_objects* input_objects, Mapfile* mapfile)
{
// Don't include the same archive twice. This can happen if
// --whole-archive is nested inside --start-group (PR gold/12163).
if (this->included_all_members_)
return true;
this->included_all_members_ = true;
input_objects->archive_start(this);
if (this->members_.size() > 0)
{
std::map<off_t, Archive_member>::const_iterator p;
for (p = this->members_.begin();
p != this->members_.end();
++p)
{
if (!this->include_member(symtab, layout, input_objects, p->first,
mapfile, NULL, "--whole-archive"))
return false;
++Archive::total_members;
}
}
else
{
for (Archive::const_iterator p = this->begin();
p != this->end();
++p)
{
if (!this->include_member(symtab, layout, input_objects, p->off,
mapfile, NULL, "--whole-archive"))
return false;
++Archive::total_members;
}
}
input_objects->archive_stop(this);
return true;
}
// Return the number of members in the archive. This is only used for
// reports.
size_t
Archive::count_members()
{
size_t ret = 0;
for (Archive::const_iterator p = this->begin();
p != this->end();
++p)
++ret;
return ret;
}
// Include an archive member in the link. OFF is the file offset of
// the member header. WHY is the reason we are including this member.
// Return true if we added the member or if we had an error, return
// false if this was the first member we tried to add from this
// archive and it had an incompatible format.
bool
Archive::include_member(Symbol_table* symtab, Layout* layout,
Input_objects* input_objects, off_t off,
Mapfile* mapfile, Symbol* sym, const char* why)
{
++Archive::total_members_loaded;
std::map<off_t, Archive_member>::const_iterator p = this->members_.find(off);
if (p != this->members_.end())
{
Object* obj = p->second.obj_;
Read_symbols_data* sd = p->second.sd_;
if (mapfile != NULL)
mapfile->report_include_archive_member(obj->name(), sym, why);
if (input_objects->add_object(obj))
{
obj->layout(symtab, layout, sd);
obj->add_symbols(symtab, sd, layout);
this->included_member_ = true;
}
delete sd;
return true;
}
// If this is the first object we are including from this archive,
// and we searched for this archive, most likely because it was
// found via a -l option, then if the target is incompatible we want
// to move on to the next archive found in the search path.
bool unconfigured = false;
bool* punconfigured = NULL;
if (!this->included_member_ && this->searched_for())
punconfigured = &unconfigured;
Object* obj = this->get_elf_object_for_member(off, punconfigured);
if (obj == NULL)
{
// Return false to search for another archive, true if we found
// an error.
return unconfigured ? false : true;
}
if (mapfile != NULL)
mapfile->report_include_archive_member(obj->name(), sym, why);
Pluginobj* pluginobj = obj->pluginobj();
if (pluginobj != NULL)
{
pluginobj->add_symbols(symtab, NULL, layout);
this->included_member_ = true;
return true;
}
if (!input_objects->add_object(obj))
{
// If this is an external member of a thin archive, unlock the
// file.
if (obj->offset() == 0)
obj->unlock(this->task_);
delete obj;
}
else
{
{
if (layout->incremental_inputs() != NULL)
layout->incremental_inputs()->report_object(obj, 0, this, NULL);
Read_symbols_data sd;
obj->read_symbols(&sd);
obj->layout(symtab, layout, &sd);
obj->add_symbols(symtab, &sd, layout);
}
// If this is an external member of a thin archive, unlock the file
// for the next task.
if (obj->offset() == 0)
obj->unlock(this->task_);
this->included_member_ = true;
}
return true;
}
// Iterate over all unused symbols, and call the visitor class V for each.
void
Archive::do_for_all_unused_symbols(Symbol_visitor_base* v) const
{
for (std::vector<Armap_entry>::const_iterator p = this->armap_.begin();
p != this->armap_.end();
++p)
{
if (this->seen_offsets_.find(p->file_offset)
== this->seen_offsets_.end())
v->visit(this->armap_names_.data() + p->name_offset);
}
}
// Print statistical information to stderr. This is used for --stats.
void
Archive::print_stats()
{
fprintf(stderr, _("%s: archive libraries: %u\n"),
program_name, Archive::total_archives);
fprintf(stderr, _("%s: total archive members: %u\n"),
program_name, Archive::total_members);
fprintf(stderr, _("%s: loaded archive members: %u\n"),
program_name, Archive::total_members_loaded);
}
// Add_archive_symbols methods.
Add_archive_symbols::~Add_archive_symbols()
{
if (this->this_blocker_ != NULL)
delete this->this_blocker_;
// next_blocker_ is deleted by the task associated with the next
// input file.
}
// Return whether we can add the archive symbols. We are blocked by
// this_blocker_. We block next_blocker_. We also lock the file.
Task_token*
Add_archive_symbols::is_runnable()
{
if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
return this->this_blocker_;
return NULL;
}
void
Add_archive_symbols::locks(Task_locker* tl)
{
tl->add(this, this->next_blocker_);
tl->add(this, this->archive_->token());
}
void
Add_archive_symbols::run(Workqueue* workqueue)
{
// For an incremental link, begin recording layout information.
Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
if (incremental_inputs != NULL)
{
unsigned int arg_serial = this->input_argument_->file().arg_serial();
Script_info* script_info = this->input_argument_->script_info();
incremental_inputs->report_archive_begin(this->archive_, arg_serial,
script_info);
}
bool added = this->archive_->add_symbols(this->symtab_, this->layout_,
this->input_objects_,
this->mapfile_);
this->archive_->unlock_nested_archives();
this->archive_->release();
this->archive_->clear_uncached_views();
if (!added)
{
// This archive holds object files which are incompatible with
// our output file.
Read_symbols::incompatible_warning(this->input_argument_,
this->archive_->input_file());
Read_symbols::requeue(workqueue, this->input_objects_, this->symtab_,
this->layout_, this->dirpath_, this->dirindex_,
this->mapfile_, this->input_argument_,
this->input_group_, this->next_blocker_);
delete this->archive_;
return;
}
if (this->input_group_ != NULL)
this->input_group_->add_archive(this->archive_);
else
{
// For an incremental link, finish recording the layout information.
if (incremental_inputs != NULL)
incremental_inputs->report_archive_end(this->archive_);
if (!parameters->options().has_plugins()
|| this->archive_->input_file()->options().whole_archive())
{
// We no longer need to know about this archive.
delete this->archive_;
}
else
{
// The plugin interface may want to rescan this archive.
parameters->options().plugins()->save_archive(this->archive_);
}
this->archive_ = NULL;
}
}
// Class Lib_group static variables.
unsigned int Lib_group::total_lib_groups;
unsigned int Lib_group::total_members;
unsigned int Lib_group::total_members_loaded;
Lib_group::Lib_group(const Input_file_lib* lib, Task* task)
: Library_base(task), members_()
{
this->members_.resize(lib->size());
}
const std::string&
Lib_group::do_filename() const
{
std::string *filename = new std::string("/group/");
return *filename;
}
// Select members from the lib group and add them to the link. We walk
// through the members, and check if each one up should be included.
// If the object says it should be included, we do so. We have to do
// this in a loop, since including one member may create new undefined
// symbols which may be satisfied by other members.
void
Lib_group::add_symbols(Symbol_table* symtab, Layout* layout,
Input_objects* input_objects)
{
++Lib_group::total_lib_groups;
Lib_group::total_members += this->members_.size();
bool added_new_object;
do
{
added_new_object = false;
unsigned int i = 0;
while (i < this->members_.size())
{
const Archive_member& member = this->members_[i];
Object* obj = member.obj_;
std::string why;
// Skip files with no symbols. Plugin objects have
// member.sd_ == NULL.
if (obj != NULL
&& (member.sd_ == NULL || member.sd_->symbol_names != NULL))
{
Archive::Should_include t = obj->should_include_member(symtab,
layout,
member.sd_,
&why);
if (t != Archive::SHOULD_INCLUDE_YES)
{
++i;
continue;
}
this->include_member(symtab, layout, input_objects, member);
added_new_object = true;
}
else
{
if (member.sd_ != NULL)
{
// The file must be locked in order to destroy the views
// associated with it.
gold_assert(obj != NULL);
obj->lock(this->task_);
delete member.sd_;
obj->unlock(this->task_);
}
}
this->members_[i] = this->members_.back();
this->members_.pop_back();
}
}
while (added_new_object);
}
// Include a lib group member in the link.
void
Lib_group::include_member(Symbol_table* symtab, Layout* layout,
Input_objects* input_objects,
const Archive_member& member)
{
++Lib_group::total_members_loaded;
Object* obj = member.obj_;
gold_assert(obj != NULL);
Pluginobj* pluginobj = obj->pluginobj();
if (pluginobj != NULL)
{
pluginobj->add_symbols(symtab, NULL, layout);
return;
}
Read_symbols_data* sd = member.sd_;
gold_assert(sd != NULL);
obj->lock(this->task_);
if (input_objects->add_object(obj))
{
if (layout->incremental_inputs() != NULL)
layout->incremental_inputs()->report_object(obj, member.arg_serial_,
this, NULL);
obj->layout(symtab, layout, sd);
obj->add_symbols(symtab, sd, layout);
}
delete sd;
// Unlock the file for the next task.
obj->unlock(this->task_);
}
// Iterate over all unused symbols, and call the visitor class V for each.
void
Lib_group::do_for_all_unused_symbols(Symbol_visitor_base* v) const
{
// Files are removed from the members list when used, so all the
// files remaining on the list are unused.
for (std::vector<Archive_member>::const_iterator p = this->members_.begin();
p != this->members_.end();
++p)
{
Object* obj = p->obj_;
obj->for_all_global_symbols(p->sd_, v);
}
}
// Print statistical information to stderr. This is used for --stats.
void
Lib_group::print_stats()
{
fprintf(stderr, _("%s: lib groups: %u\n"),
program_name, Lib_group::total_lib_groups);
fprintf(stderr, _("%s: total lib groups members: %u\n"),
program_name, Lib_group::total_members);
fprintf(stderr, _("%s: loaded lib groups members: %u\n"),
program_name, Lib_group::total_members_loaded);
}
Task_token*
Add_lib_group_symbols::is_runnable()
{
if (this->readsyms_blocker_ != NULL && this->readsyms_blocker_->is_blocked())
return this->readsyms_blocker_;
if (this->this_blocker_ != NULL && this->this_blocker_->is_blocked())
return this->this_blocker_;
return NULL;
}
void
Add_lib_group_symbols::locks(Task_locker* tl)
{
tl->add(this, this->next_blocker_);
}
void
Add_lib_group_symbols::run(Workqueue*)
{
// For an incremental link, begin recording layout information.
Incremental_inputs* incremental_inputs = this->layout_->incremental_inputs();
if (incremental_inputs != NULL)
incremental_inputs->report_archive_begin(this->lib_, 0, NULL);
this->lib_->add_symbols(this->symtab_, this->layout_, this->input_objects_);
if (incremental_inputs != NULL)
incremental_inputs->report_archive_end(this->lib_);
}
Add_lib_group_symbols::~Add_lib_group_symbols()
{
if (this->this_blocker_ != NULL)
delete this->this_blocker_;
// next_blocker_ is deleted by the task associated with the next
// input file.
}
} // End namespace gold.
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