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913 lines
26 KiB
C
913 lines
26 KiB
C
/* hash.c -- hash table routines for BFD
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Copyright (C) 1993-2014 Free Software Foundation, Inc.
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Written by Steve Chamberlain <sac@cygnus.com>
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This file is part of BFD, the Binary File Descriptor library.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
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MA 02110-1301, USA. */
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#include "sysdep.h"
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#include "bfd.h"
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#include "libbfd.h"
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#include "objalloc.h"
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#include "libiberty.h"
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/*
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SECTION
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Hash Tables
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@cindex Hash tables
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BFD provides a simple set of hash table functions. Routines
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are provided to initialize a hash table, to free a hash table,
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to look up a string in a hash table and optionally create an
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entry for it, and to traverse a hash table. There is
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currently no routine to delete an string from a hash table.
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The basic hash table does not permit any data to be stored
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with a string. However, a hash table is designed to present a
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base class from which other types of hash tables may be
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derived. These derived types may store additional information
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with the string. Hash tables were implemented in this way,
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rather than simply providing a data pointer in a hash table
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entry, because they were designed for use by the linker back
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ends. The linker may create thousands of hash table entries,
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and the overhead of allocating private data and storing and
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following pointers becomes noticeable.
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The basic hash table code is in <<hash.c>>.
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@menu
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@* Creating and Freeing a Hash Table::
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@* Looking Up or Entering a String::
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@* Traversing a Hash Table::
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@* Deriving a New Hash Table Type::
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@end menu
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INODE
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Creating and Freeing a Hash Table, Looking Up or Entering a String, Hash Tables, Hash Tables
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SUBSECTION
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Creating and freeing a hash table
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@findex bfd_hash_table_init
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@findex bfd_hash_table_init_n
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To create a hash table, create an instance of a <<struct
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bfd_hash_table>> (defined in <<bfd.h>>) and call
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<<bfd_hash_table_init>> (if you know approximately how many
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entries you will need, the function <<bfd_hash_table_init_n>>,
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which takes a @var{size} argument, may be used).
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<<bfd_hash_table_init>> returns <<FALSE>> if some sort of
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error occurs.
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@findex bfd_hash_newfunc
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The function <<bfd_hash_table_init>> take as an argument a
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function to use to create new entries. For a basic hash
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table, use the function <<bfd_hash_newfunc>>. @xref{Deriving
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a New Hash Table Type}, for why you would want to use a
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different value for this argument.
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@findex bfd_hash_allocate
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<<bfd_hash_table_init>> will create an objalloc which will be
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used to allocate new entries. You may allocate memory on this
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objalloc using <<bfd_hash_allocate>>.
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@findex bfd_hash_table_free
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Use <<bfd_hash_table_free>> to free up all the memory that has
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been allocated for a hash table. This will not free up the
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<<struct bfd_hash_table>> itself, which you must provide.
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@findex bfd_hash_set_default_size
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Use <<bfd_hash_set_default_size>> to set the default size of
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hash table to use.
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INODE
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Looking Up or Entering a String, Traversing a Hash Table, Creating and Freeing a Hash Table, Hash Tables
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SUBSECTION
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Looking up or entering a string
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@findex bfd_hash_lookup
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The function <<bfd_hash_lookup>> is used both to look up a
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string in the hash table and to create a new entry.
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If the @var{create} argument is <<FALSE>>, <<bfd_hash_lookup>>
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will look up a string. If the string is found, it will
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returns a pointer to a <<struct bfd_hash_entry>>. If the
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string is not found in the table <<bfd_hash_lookup>> will
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return <<NULL>>. You should not modify any of the fields in
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the returns <<struct bfd_hash_entry>>.
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If the @var{create} argument is <<TRUE>>, the string will be
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entered into the hash table if it is not already there.
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Either way a pointer to a <<struct bfd_hash_entry>> will be
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returned, either to the existing structure or to a newly
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created one. In this case, a <<NULL>> return means that an
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error occurred.
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If the @var{create} argument is <<TRUE>>, and a new entry is
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created, the @var{copy} argument is used to decide whether to
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copy the string onto the hash table objalloc or not. If
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@var{copy} is passed as <<FALSE>>, you must be careful not to
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deallocate or modify the string as long as the hash table
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exists.
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INODE
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Traversing a Hash Table, Deriving a New Hash Table Type, Looking Up or Entering a String, Hash Tables
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SUBSECTION
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Traversing a hash table
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@findex bfd_hash_traverse
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The function <<bfd_hash_traverse>> may be used to traverse a
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hash table, calling a function on each element. The traversal
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is done in a random order.
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<<bfd_hash_traverse>> takes as arguments a function and a
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generic <<void *>> pointer. The function is called with a
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hash table entry (a <<struct bfd_hash_entry *>>) and the
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generic pointer passed to <<bfd_hash_traverse>>. The function
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must return a <<boolean>> value, which indicates whether to
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continue traversing the hash table. If the function returns
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<<FALSE>>, <<bfd_hash_traverse>> will stop the traversal and
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return immediately.
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INODE
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Deriving a New Hash Table Type, , Traversing a Hash Table, Hash Tables
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SUBSECTION
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Deriving a new hash table type
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Many uses of hash tables want to store additional information
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which each entry in the hash table. Some also find it
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convenient to store additional information with the hash table
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itself. This may be done using a derived hash table.
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Since C is not an object oriented language, creating a derived
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hash table requires sticking together some boilerplate
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routines with a few differences specific to the type of hash
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table you want to create.
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An example of a derived hash table is the linker hash table.
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The structures for this are defined in <<bfdlink.h>>. The
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functions are in <<linker.c>>.
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You may also derive a hash table from an already derived hash
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table. For example, the a.out linker backend code uses a hash
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table derived from the linker hash table.
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@menu
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@* Define the Derived Structures::
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@* Write the Derived Creation Routine::
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@* Write Other Derived Routines::
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@end menu
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INODE
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Define the Derived Structures, Write the Derived Creation Routine, Deriving a New Hash Table Type, Deriving a New Hash Table Type
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SUBSUBSECTION
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Define the derived structures
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You must define a structure for an entry in the hash table,
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and a structure for the hash table itself.
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The first field in the structure for an entry in the hash
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table must be of the type used for an entry in the hash table
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you are deriving from. If you are deriving from a basic hash
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table this is <<struct bfd_hash_entry>>, which is defined in
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<<bfd.h>>. The first field in the structure for the hash
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table itself must be of the type of the hash table you are
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deriving from itself. If you are deriving from a basic hash
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table, this is <<struct bfd_hash_table>>.
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For example, the linker hash table defines <<struct
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bfd_link_hash_entry>> (in <<bfdlink.h>>). The first field,
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<<root>>, is of type <<struct bfd_hash_entry>>. Similarly,
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the first field in <<struct bfd_link_hash_table>>, <<table>>,
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is of type <<struct bfd_hash_table>>.
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INODE
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Write the Derived Creation Routine, Write Other Derived Routines, Define the Derived Structures, Deriving a New Hash Table Type
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SUBSUBSECTION
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Write the derived creation routine
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You must write a routine which will create and initialize an
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entry in the hash table. This routine is passed as the
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function argument to <<bfd_hash_table_init>>.
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In order to permit other hash tables to be derived from the
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hash table you are creating, this routine must be written in a
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standard way.
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The first argument to the creation routine is a pointer to a
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hash table entry. This may be <<NULL>>, in which case the
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routine should allocate the right amount of space. Otherwise
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the space has already been allocated by a hash table type
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derived from this one.
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After allocating space, the creation routine must call the
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creation routine of the hash table type it is derived from,
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passing in a pointer to the space it just allocated. This
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will initialize any fields used by the base hash table.
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Finally the creation routine must initialize any local fields
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for the new hash table type.
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Here is a boilerplate example of a creation routine.
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@var{function_name} is the name of the routine.
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@var{entry_type} is the type of an entry in the hash table you
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are creating. @var{base_newfunc} is the name of the creation
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routine of the hash table type your hash table is derived
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from.
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EXAMPLE
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.struct bfd_hash_entry *
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.@var{function_name} (struct bfd_hash_entry *entry,
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. struct bfd_hash_table *table,
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. const char *string)
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.{
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. struct @var{entry_type} *ret = (@var{entry_type} *) entry;
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.
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. {* Allocate the structure if it has not already been allocated by a
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. derived class. *}
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. if (ret == NULL)
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. {
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. ret = bfd_hash_allocate (table, sizeof (* ret));
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. if (ret == NULL)
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. return NULL;
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. }
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.
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. {* Call the allocation method of the base class. *}
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. ret = ((@var{entry_type} *)
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. @var{base_newfunc} ((struct bfd_hash_entry *) ret, table, string));
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.
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. {* Initialize the local fields here. *}
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.
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. return (struct bfd_hash_entry *) ret;
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.}
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DESCRIPTION
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The creation routine for the linker hash table, which is in
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<<linker.c>>, looks just like this example.
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@var{function_name} is <<_bfd_link_hash_newfunc>>.
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@var{entry_type} is <<struct bfd_link_hash_entry>>.
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@var{base_newfunc} is <<bfd_hash_newfunc>>, the creation
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routine for a basic hash table.
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<<_bfd_link_hash_newfunc>> also initializes the local fields
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in a linker hash table entry: <<type>>, <<written>> and
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<<next>>.
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INODE
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Write Other Derived Routines, , Write the Derived Creation Routine, Deriving a New Hash Table Type
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SUBSUBSECTION
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Write other derived routines
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You will want to write other routines for your new hash table,
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as well.
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You will want an initialization routine which calls the
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initialization routine of the hash table you are deriving from
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and initializes any other local fields. For the linker hash
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table, this is <<_bfd_link_hash_table_init>> in <<linker.c>>.
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You will want a lookup routine which calls the lookup routine
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of the hash table you are deriving from and casts the result.
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The linker hash table uses <<bfd_link_hash_lookup>> in
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<<linker.c>> (this actually takes an additional argument which
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it uses to decide how to return the looked up value).
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You may want a traversal routine. This should just call the
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traversal routine of the hash table you are deriving from with
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appropriate casts. The linker hash table uses
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<<bfd_link_hash_traverse>> in <<linker.c>>.
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These routines may simply be defined as macros. For example,
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the a.out backend linker hash table, which is derived from the
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linker hash table, uses macros for the lookup and traversal
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routines. These are <<aout_link_hash_lookup>> and
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<<aout_link_hash_traverse>> in aoutx.h.
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*/
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/* The default number of entries to use when creating a hash table. */
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#define DEFAULT_SIZE 4051
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/* The following function returns a nearest prime number which is
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greater than N, and near a power of two. Copied from libiberty.
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Returns zero for ridiculously large N to signify an error. */
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static unsigned long
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higher_prime_number (unsigned long n)
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{
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/* These are primes that are near, but slightly smaller than, a
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power of two. */
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static const unsigned long primes[] =
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{
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(unsigned long) 31,
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(unsigned long) 61,
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(unsigned long) 127,
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(unsigned long) 251,
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(unsigned long) 509,
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(unsigned long) 1021,
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(unsigned long) 2039,
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(unsigned long) 4093,
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(unsigned long) 8191,
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(unsigned long) 16381,
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(unsigned long) 32749,
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(unsigned long) 65521,
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(unsigned long) 131071,
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(unsigned long) 262139,
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(unsigned long) 524287,
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(unsigned long) 1048573,
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(unsigned long) 2097143,
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(unsigned long) 4194301,
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(unsigned long) 8388593,
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(unsigned long) 16777213,
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(unsigned long) 33554393,
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(unsigned long) 67108859,
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(unsigned long) 134217689,
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(unsigned long) 268435399,
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(unsigned long) 536870909,
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(unsigned long) 1073741789,
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(unsigned long) 2147483647,
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/* 4294967291L */
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((unsigned long) 2147483647) + ((unsigned long) 2147483644),
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};
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const unsigned long *low = &primes[0];
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const unsigned long *high = &primes[sizeof (primes) / sizeof (primes[0])];
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while (low != high)
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{
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const unsigned long *mid = low + (high - low) / 2;
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if (n >= *mid)
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low = mid + 1;
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else
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high = mid;
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}
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if (n >= *low)
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return 0;
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return *low;
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}
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static unsigned long bfd_default_hash_table_size = DEFAULT_SIZE;
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/* Create a new hash table, given a number of entries. */
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bfd_boolean
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bfd_hash_table_init_n (struct bfd_hash_table *table,
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struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
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struct bfd_hash_table *,
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const char *),
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unsigned int entsize,
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unsigned int size)
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{
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unsigned long alloc;
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alloc = size;
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alloc *= sizeof (struct bfd_hash_entry *);
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if (alloc / sizeof (struct bfd_hash_entry *) != size)
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{
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bfd_set_error (bfd_error_no_memory);
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return FALSE;
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}
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table->memory = (void *) objalloc_create ();
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if (table->memory == NULL)
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{
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bfd_set_error (bfd_error_no_memory);
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return FALSE;
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}
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table->table = (struct bfd_hash_entry **)
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objalloc_alloc ((struct objalloc *) table->memory, alloc);
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if (table->table == NULL)
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{
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bfd_hash_table_free (table);
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bfd_set_error (bfd_error_no_memory);
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return FALSE;
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}
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memset ((void *) table->table, 0, alloc);
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table->size = size;
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table->entsize = entsize;
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table->count = 0;
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table->frozen = 0;
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table->newfunc = newfunc;
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return TRUE;
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}
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/* Create a new hash table with the default number of entries. */
|
||
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||
bfd_boolean
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bfd_hash_table_init (struct bfd_hash_table *table,
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struct bfd_hash_entry *(*newfunc) (struct bfd_hash_entry *,
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struct bfd_hash_table *,
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const char *),
|
||
unsigned int entsize)
|
||
{
|
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return bfd_hash_table_init_n (table, newfunc, entsize,
|
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bfd_default_hash_table_size);
|
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}
|
||
|
||
/* Free a hash table. */
|
||
|
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void
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bfd_hash_table_free (struct bfd_hash_table *table)
|
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{
|
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objalloc_free ((struct objalloc *) table->memory);
|
||
table->memory = NULL;
|
||
}
|
||
|
||
static inline unsigned long
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bfd_hash_hash (const char *string, unsigned int *lenp)
|
||
{
|
||
const unsigned char *s;
|
||
unsigned long hash;
|
||
unsigned int len;
|
||
unsigned int c;
|
||
|
||
hash = 0;
|
||
len = 0;
|
||
s = (const unsigned char *) string;
|
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while ((c = *s++) != '\0')
|
||
{
|
||
hash += c + (c << 17);
|
||
hash ^= hash >> 2;
|
||
}
|
||
len = (s - (const unsigned char *) string) - 1;
|
||
hash += len + (len << 17);
|
||
hash ^= hash >> 2;
|
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if (lenp != NULL)
|
||
*lenp = len;
|
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return hash;
|
||
}
|
||
|
||
/* Look up a string in a hash table. */
|
||
|
||
struct bfd_hash_entry *
|
||
bfd_hash_lookup (struct bfd_hash_table *table,
|
||
const char *string,
|
||
bfd_boolean create,
|
||
bfd_boolean copy)
|
||
{
|
||
unsigned long hash;
|
||
struct bfd_hash_entry *hashp;
|
||
unsigned int len;
|
||
unsigned int _index;
|
||
|
||
hash = bfd_hash_hash (string, &len);
|
||
_index = hash % table->size;
|
||
for (hashp = table->table[_index];
|
||
hashp != NULL;
|
||
hashp = hashp->next)
|
||
{
|
||
if (hashp->hash == hash
|
||
&& strcmp (hashp->string, string) == 0)
|
||
return hashp;
|
||
}
|
||
|
||
if (! create)
|
||
return NULL;
|
||
|
||
if (copy)
|
||
{
|
||
char *new_string;
|
||
|
||
new_string = (char *) objalloc_alloc ((struct objalloc *) table->memory,
|
||
len + 1);
|
||
if (!new_string)
|
||
{
|
||
bfd_set_error (bfd_error_no_memory);
|
||
return NULL;
|
||
}
|
||
memcpy (new_string, string, len + 1);
|
||
string = new_string;
|
||
}
|
||
|
||
return bfd_hash_insert (table, string, hash);
|
||
}
|
||
|
||
/* Insert an entry in a hash table. */
|
||
|
||
struct bfd_hash_entry *
|
||
bfd_hash_insert (struct bfd_hash_table *table,
|
||
const char *string,
|
||
unsigned long hash)
|
||
{
|
||
struct bfd_hash_entry *hashp;
|
||
unsigned int _index;
|
||
|
||
hashp = (*table->newfunc) (NULL, table, string);
|
||
if (hashp == NULL)
|
||
return NULL;
|
||
hashp->string = string;
|
||
hashp->hash = hash;
|
||
_index = hash % table->size;
|
||
hashp->next = table->table[_index];
|
||
table->table[_index] = hashp;
|
||
table->count++;
|
||
|
||
if (!table->frozen && table->count > table->size * 3 / 4)
|
||
{
|
||
unsigned long newsize = higher_prime_number (table->size);
|
||
struct bfd_hash_entry **newtable;
|
||
unsigned int hi;
|
||
unsigned long alloc = newsize * sizeof (struct bfd_hash_entry *);
|
||
|
||
/* If we can't find a higher prime, or we can't possibly alloc
|
||
that much memory, don't try to grow the table. */
|
||
if (newsize == 0 || alloc / sizeof (struct bfd_hash_entry *) != newsize)
|
||
{
|
||
table->frozen = 1;
|
||
return hashp;
|
||
}
|
||
|
||
newtable = ((struct bfd_hash_entry **)
|
||
objalloc_alloc ((struct objalloc *) table->memory, alloc));
|
||
if (newtable == NULL)
|
||
{
|
||
table->frozen = 1;
|
||
return hashp;
|
||
}
|
||
memset (newtable, 0, alloc);
|
||
|
||
for (hi = 0; hi < table->size; hi ++)
|
||
while (table->table[hi])
|
||
{
|
||
struct bfd_hash_entry *chain = table->table[hi];
|
||
struct bfd_hash_entry *chain_end = chain;
|
||
|
||
while (chain_end->next && chain_end->next->hash == chain->hash)
|
||
chain_end = chain_end->next;
|
||
|
||
table->table[hi] = chain_end->next;
|
||
_index = chain->hash % newsize;
|
||
chain_end->next = newtable[_index];
|
||
newtable[_index] = chain;
|
||
}
|
||
table->table = newtable;
|
||
table->size = newsize;
|
||
}
|
||
|
||
return hashp;
|
||
}
|
||
|
||
/* Rename an entry in a hash table. */
|
||
|
||
void
|
||
bfd_hash_rename (struct bfd_hash_table *table,
|
||
const char *string,
|
||
struct bfd_hash_entry *ent)
|
||
{
|
||
unsigned int _index;
|
||
struct bfd_hash_entry **pph;
|
||
|
||
_index = ent->hash % table->size;
|
||
for (pph = &table->table[_index]; *pph != NULL; pph = &(*pph)->next)
|
||
if (*pph == ent)
|
||
break;
|
||
if (*pph == NULL)
|
||
abort ();
|
||
|
||
*pph = ent->next;
|
||
ent->string = string;
|
||
ent->hash = bfd_hash_hash (string, NULL);
|
||
_index = ent->hash % table->size;
|
||
ent->next = table->table[_index];
|
||
table->table[_index] = ent;
|
||
}
|
||
|
||
/* Replace an entry in a hash table. */
|
||
|
||
void
|
||
bfd_hash_replace (struct bfd_hash_table *table,
|
||
struct bfd_hash_entry *old,
|
||
struct bfd_hash_entry *nw)
|
||
{
|
||
unsigned int _index;
|
||
struct bfd_hash_entry **pph;
|
||
|
||
_index = old->hash % table->size;
|
||
for (pph = &table->table[_index];
|
||
(*pph) != NULL;
|
||
pph = &(*pph)->next)
|
||
{
|
||
if (*pph == old)
|
||
{
|
||
*pph = nw;
|
||
return;
|
||
}
|
||
}
|
||
|
||
abort ();
|
||
}
|
||
|
||
/* Allocate space in a hash table. */
|
||
|
||
void *
|
||
bfd_hash_allocate (struct bfd_hash_table *table,
|
||
unsigned int size)
|
||
{
|
||
void * ret;
|
||
|
||
ret = objalloc_alloc ((struct objalloc *) table->memory, size);
|
||
if (ret == NULL && size != 0)
|
||
bfd_set_error (bfd_error_no_memory);
|
||
return ret;
|
||
}
|
||
|
||
/* Base method for creating a new hash table entry. */
|
||
|
||
struct bfd_hash_entry *
|
||
bfd_hash_newfunc (struct bfd_hash_entry *entry,
|
||
struct bfd_hash_table *table,
|
||
const char *string ATTRIBUTE_UNUSED)
|
||
{
|
||
if (entry == NULL)
|
||
entry = (struct bfd_hash_entry *) bfd_hash_allocate (table,
|
||
sizeof (* entry));
|
||
return entry;
|
||
}
|
||
|
||
/* Traverse a hash table. */
|
||
|
||
void
|
||
bfd_hash_traverse (struct bfd_hash_table *table,
|
||
bfd_boolean (*func) (struct bfd_hash_entry *, void *),
|
||
void * info)
|
||
{
|
||
unsigned int i;
|
||
|
||
table->frozen = 1;
|
||
for (i = 0; i < table->size; i++)
|
||
{
|
||
struct bfd_hash_entry *p;
|
||
|
||
for (p = table->table[i]; p != NULL; p = p->next)
|
||
if (! (*func) (p, info))
|
||
goto out;
|
||
}
|
||
out:
|
||
table->frozen = 0;
|
||
}
|
||
|
||
unsigned long
|
||
bfd_hash_set_default_size (unsigned long hash_size)
|
||
{
|
||
/* Extend this prime list if you want more granularity of hash table size. */
|
||
static const unsigned long hash_size_primes[] =
|
||
{
|
||
31, 61, 127, 251, 509, 1021, 2039, 4091, 8191, 16381, 32749, 65537
|
||
};
|
||
unsigned int _index;
|
||
|
||
/* Work out best prime number near the hash_size. */
|
||
for (_index = 0; _index < ARRAY_SIZE (hash_size_primes) - 1; ++_index)
|
||
if (hash_size <= hash_size_primes[_index])
|
||
break;
|
||
|
||
bfd_default_hash_table_size = hash_size_primes[_index];
|
||
return bfd_default_hash_table_size;
|
||
}
|
||
|
||
/* A few different object file formats (a.out, COFF, ELF) use a string
|
||
table. These functions support adding strings to a string table,
|
||
returning the byte offset, and writing out the table.
|
||
|
||
Possible improvements:
|
||
+ look for strings matching trailing substrings of other strings
|
||
+ better data structures? balanced trees?
|
||
+ look at reducing memory use elsewhere -- maybe if we didn't have
|
||
to construct the entire symbol table at once, we could get by
|
||
with smaller amounts of VM? (What effect does that have on the
|
||
string table reductions?) */
|
||
|
||
/* An entry in the strtab hash table. */
|
||
|
||
struct strtab_hash_entry
|
||
{
|
||
struct bfd_hash_entry root;
|
||
/* Index in string table. */
|
||
bfd_size_type index;
|
||
/* Next string in strtab. */
|
||
struct strtab_hash_entry *next;
|
||
};
|
||
|
||
/* The strtab hash table. */
|
||
|
||
struct bfd_strtab_hash
|
||
{
|
||
struct bfd_hash_table table;
|
||
/* Size of strtab--also next available index. */
|
||
bfd_size_type size;
|
||
/* First string in strtab. */
|
||
struct strtab_hash_entry *first;
|
||
/* Last string in strtab. */
|
||
struct strtab_hash_entry *last;
|
||
/* Whether to precede strings with a two byte length, as in the
|
||
XCOFF .debug section. */
|
||
bfd_boolean xcoff;
|
||
};
|
||
|
||
/* Routine to create an entry in a strtab. */
|
||
|
||
static struct bfd_hash_entry *
|
||
strtab_hash_newfunc (struct bfd_hash_entry *entry,
|
||
struct bfd_hash_table *table,
|
||
const char *string)
|
||
{
|
||
struct strtab_hash_entry *ret = (struct strtab_hash_entry *) entry;
|
||
|
||
/* Allocate the structure if it has not already been allocated by a
|
||
subclass. */
|
||
if (ret == NULL)
|
||
ret = (struct strtab_hash_entry *) bfd_hash_allocate (table,
|
||
sizeof (* ret));
|
||
if (ret == NULL)
|
||
return NULL;
|
||
|
||
/* Call the allocation method of the superclass. */
|
||
ret = (struct strtab_hash_entry *)
|
||
bfd_hash_newfunc ((struct bfd_hash_entry *) ret, table, string);
|
||
|
||
if (ret)
|
||
{
|
||
/* Initialize the local fields. */
|
||
ret->index = (bfd_size_type) -1;
|
||
ret->next = NULL;
|
||
}
|
||
|
||
return (struct bfd_hash_entry *) ret;
|
||
}
|
||
|
||
/* Look up an entry in an strtab. */
|
||
|
||
#define strtab_hash_lookup(t, string, create, copy) \
|
||
((struct strtab_hash_entry *) \
|
||
bfd_hash_lookup (&(t)->table, (string), (create), (copy)))
|
||
|
||
/* Create a new strtab. */
|
||
|
||
struct bfd_strtab_hash *
|
||
_bfd_stringtab_init (void)
|
||
{
|
||
struct bfd_strtab_hash *table;
|
||
bfd_size_type amt = sizeof (* table);
|
||
|
||
table = (struct bfd_strtab_hash *) bfd_malloc (amt);
|
||
if (table == NULL)
|
||
return NULL;
|
||
|
||
if (!bfd_hash_table_init (&table->table, strtab_hash_newfunc,
|
||
sizeof (struct strtab_hash_entry)))
|
||
{
|
||
free (table);
|
||
return NULL;
|
||
}
|
||
|
||
table->size = 0;
|
||
table->first = NULL;
|
||
table->last = NULL;
|
||
table->xcoff = FALSE;
|
||
|
||
return table;
|
||
}
|
||
|
||
/* Create a new strtab in which the strings are output in the format
|
||
used in the XCOFF .debug section: a two byte length precedes each
|
||
string. */
|
||
|
||
struct bfd_strtab_hash *
|
||
_bfd_xcoff_stringtab_init (void)
|
||
{
|
||
struct bfd_strtab_hash *ret;
|
||
|
||
ret = _bfd_stringtab_init ();
|
||
if (ret != NULL)
|
||
ret->xcoff = TRUE;
|
||
return ret;
|
||
}
|
||
|
||
/* Free a strtab. */
|
||
|
||
void
|
||
_bfd_stringtab_free (struct bfd_strtab_hash *table)
|
||
{
|
||
bfd_hash_table_free (&table->table);
|
||
free (table);
|
||
}
|
||
|
||
/* Get the index of a string in a strtab, adding it if it is not
|
||
already present. If HASH is FALSE, we don't really use the hash
|
||
table, and we don't eliminate duplicate strings. If COPY is true
|
||
then store a copy of STR if creating a new entry. */
|
||
|
||
bfd_size_type
|
||
_bfd_stringtab_add (struct bfd_strtab_hash *tab,
|
||
const char *str,
|
||
bfd_boolean hash,
|
||
bfd_boolean copy)
|
||
{
|
||
struct strtab_hash_entry *entry;
|
||
|
||
if (hash)
|
||
{
|
||
entry = strtab_hash_lookup (tab, str, TRUE, copy);
|
||
if (entry == NULL)
|
||
return (bfd_size_type) -1;
|
||
}
|
||
else
|
||
{
|
||
entry = (struct strtab_hash_entry *) bfd_hash_allocate (&tab->table,
|
||
sizeof (* entry));
|
||
if (entry == NULL)
|
||
return (bfd_size_type) -1;
|
||
if (! copy)
|
||
entry->root.string = str;
|
||
else
|
||
{
|
||
size_t len = strlen (str) + 1;
|
||
char *n;
|
||
|
||
n = (char *) bfd_hash_allocate (&tab->table, len);
|
||
if (n == NULL)
|
||
return (bfd_size_type) -1;
|
||
memcpy (n, str, len);
|
||
entry->root.string = n;
|
||
}
|
||
entry->index = (bfd_size_type) -1;
|
||
entry->next = NULL;
|
||
}
|
||
|
||
if (entry->index == (bfd_size_type) -1)
|
||
{
|
||
entry->index = tab->size;
|
||
tab->size += strlen (str) + 1;
|
||
if (tab->xcoff)
|
||
{
|
||
entry->index += 2;
|
||
tab->size += 2;
|
||
}
|
||
if (tab->first == NULL)
|
||
tab->first = entry;
|
||
else
|
||
tab->last->next = entry;
|
||
tab->last = entry;
|
||
}
|
||
|
||
return entry->index;
|
||
}
|
||
|
||
/* Get the number of bytes in a strtab. */
|
||
|
||
bfd_size_type
|
||
_bfd_stringtab_size (struct bfd_strtab_hash *tab)
|
||
{
|
||
return tab->size;
|
||
}
|
||
|
||
/* Write out a strtab. ABFD must already be at the right location in
|
||
the file. */
|
||
|
||
bfd_boolean
|
||
_bfd_stringtab_emit (bfd *abfd, struct bfd_strtab_hash *tab)
|
||
{
|
||
bfd_boolean xcoff;
|
||
struct strtab_hash_entry *entry;
|
||
|
||
xcoff = tab->xcoff;
|
||
|
||
for (entry = tab->first; entry != NULL; entry = entry->next)
|
||
{
|
||
const char *str;
|
||
size_t len;
|
||
|
||
str = entry->root.string;
|
||
len = strlen (str) + 1;
|
||
|
||
if (xcoff)
|
||
{
|
||
bfd_byte buf[2];
|
||
|
||
/* The output length includes the null byte. */
|
||
bfd_put_16 (abfd, (bfd_vma) len, buf);
|
||
if (bfd_bwrite ((void *) buf, (bfd_size_type) 2, abfd) != 2)
|
||
return FALSE;
|
||
}
|
||
|
||
if (bfd_bwrite ((void *) str, (bfd_size_type) len, abfd) != len)
|
||
return FALSE;
|
||
}
|
||
|
||
return TRUE;
|
||
}
|