/* Support for the generic parts of most COFF variants, for BFD.   Copyright 1990-2013 Free Software Foundation, Inc.   Written by Cygnus Support.    This file is part of BFD, the Binary File Descriptor library.    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.  */ /* Most of this hacked by  Steve Chamberlain,			sac@cygnus.com.  *//*SECTION	coff backends 	BFD supports a number of different flavours of coff format.	The major differences between formats are the sizes and	alignments of fields in structures on disk, and the occasional	extra field. 	Coff in all its varieties is implemented with a few common	files and a number of implementation specific files. For	example, The 88k bcs coff format is implemented in the file	@file{coff-m88k.c}. This file @code{#include}s	@file{coff/m88k.h} which defines the external structure of the	coff format for the 88k, and @file{coff/internal.h} which	defines the internal structure. @file{coff-m88k.c} also	defines the relocations used by the 88k format	@xref{Relocations}. 	The Intel i960 processor version of coff is implemented in	@file{coff-i960.c}. This file has the same structure as	@file{coff-m88k.c}, except that it includes @file{coff/i960.h}	rather than @file{coff-m88k.h}. SUBSECTION	Porting to a new version of coff 	The recommended method is to select from the existing	implementations the version of coff which is most like the one	you want to use.  For example, we'll say that i386 coff is	the one you select, and that your coff flavour is called foo.	Copy @file{i386coff.c} to @file{foocoff.c}, copy	@file{../include/coff/i386.h} to @file{../include/coff/foo.h},	and add the lines to @file{targets.c} and @file{Makefile.in}	so that your new back end is used. Alter the shapes of the	structures in @file{../include/coff/foo.h} so that they match	what you need. You will probably also have to add	@code{#ifdef}s to the code in @file{coff/internal.h} and	@file{coffcode.h} if your version of coff is too wild. 	You can verify that your new BFD backend works quite simply by	building @file{objdump} from the @file{binutils} directory,	and making sure that its version of what's going on and your	host system's idea (assuming it has the pretty standard coff	dump utility, usually called @code{att-dump} or just	@code{dump}) are the same.  Then clean up your code, and send	what you've done to Cygnus. Then your stuff will be in the	next release, and you won't have to keep integrating it. SUBSECTION	How the coff backend works SUBSUBSECTION	File layout 	The Coff backend is split into generic routines that are	applicable to any Coff target and routines that are specific	to a particular target.  The target-specific routines are	further split into ones which are basically the same for all	Coff targets except that they use the external symbol format	or use different values for certain constants. 	The generic routines are in @file{coffgen.c}.  These routines	work for any Coff target.  They use some hooks into the target	specific code; the hooks are in a @code{bfd_coff_backend_data}	structure, one of which exists for each target. 	The essentially similar target-specific routines are in	@file{coffcode.h}.  This header file includes executable C code.	The various Coff targets first include the appropriate Coff	header file, make any special defines that are needed, and	then include @file{coffcode.h}. 	Some of the Coff targets then also have additional routines in	the target source file itself. 	For example, @file{coff-i960.c} includes	@file{coff/internal.h} and @file{coff/i960.h}.  It then	defines a few constants, such as @code{I960}, and includes	@file{coffcode.h}.  Since the i960 has complex relocation	types, @file{coff-i960.c} also includes some code to	manipulate the i960 relocs.  This code is not in	@file{coffcode.h} because it would not be used by any other	target. SUBSUBSECTION	Coff long section names 	In the standard Coff object format, section names are limited to	the eight bytes available in the @code{s_name} field of the	@code{SCNHDR} section header structure.  The format requires the	field to be NUL-padded, but not necessarily NUL-terminated, so	the longest section names permitted are a full eight characters. 	The Microsoft PE variants of the Coff object file format add	an extension to support the use of long section names.  This	extension is defined in section 4 of the Microsoft PE/COFF	specification (rev 8.1).  If a section name is too long to fit	into the section header's @code{s_name} field, it is instead	placed into the string table, and the @code{s_name} field is	filled with a slash ("/") followed by the ASCII decimal	representation of the offset of the full name relative to the	string table base. 	Note that this implies that the extension can only be used in object	files, as executables do not contain a string table.  The standard	specifies that long section names from objects emitted into executable	images are to be truncated. 	However, as a GNU extension, BFD can generate executable images	that contain a string table and long section names.  This	would appear to be technically valid, as the standard only says	that Coff debugging information is deprecated, not forbidden,	and in practice it works, although some tools that parse PE files	expecting the MS standard format may become confused; @file{PEview} is	one known example. 	The functionality is supported in BFD by code implemented under	the control of the macro @code{COFF_LONG_SECTION_NAMES}.  If not	defined, the format does not support long section names in any way.	If defined, it is used to initialise a flag,	@code{_bfd_coff_long_section_names}, and a hook function pointer,	@code{_bfd_coff_set_long_section_names}, in the Coff backend data	structure.  The flag controls the generation of long section names	in output BFDs at runtime; if it is false, as it will be by default	when generating an executable image, long section names are truncated;	if true, the long section names extension is employed.  The hook	points to a function that allows the value of the flag to be altered	at runtime, on formats that support long section names at all; on	other formats it points to a stub that returns an error indication. 	With input BFDs, the flag is set according to whether any long section	names are detected while reading the section headers.  For a completely	new BFD, the flag is set to the default for the target format.  This	information can be used by a client of the BFD library when deciding	what output format to generate, and means that a BFD that is opened	for read and subsequently converted to a writeable BFD and modified	in-place will retain whatever format it had on input. 	If @code{COFF_LONG_SECTION_NAMES} is simply defined (blank), or is	defined to the value "1", then long section names are enabled by	default; if it is defined to the value zero, they are disabled by	default (but still accepted in input BFDs).  The header @file{coffcode.h}	defines a macro, @code{COFF_DEFAULT_LONG_SECTION_NAMES}, which is	used in the backends to initialise the backend data structure fields	appropriately; see the comments for further detail. SUBSUBSECTION	Bit twiddling 	Each flavour of coff supported in BFD has its own header file	describing the external layout of the structures. There is also	an internal description of the coff layout, in	@file{coff/internal.h}. A major function of the	coff backend is swapping the bytes and twiddling the bits to	translate the external form of the structures into the normal	internal form. This is all performed in the	@code{bfd_swap}_@i{thing}_@i{direction} routines. Some	elements are different sizes between different versions of	coff; it is the duty of the coff version specific include file	to override the definitions of various packing routines in	@file{coffcode.h}. E.g., the size of line number entry in coff is	sometimes 16 bits, and sometimes 32 bits. @code{#define}ing	@code{PUT_LNSZ_LNNO} and @code{GET_LNSZ_LNNO} will select the	correct one. No doubt, some day someone will find a version of	coff which has a varying field size not catered to at the	moment. To port BFD, that person will have to add more @code{#defines}.	Three of the bit twiddling routines are exported to	@code{gdb}; @code{coff_swap_aux_in}, @code{coff_swap_sym_in}	and @code{coff_swap_lineno_in}. @code{GDB} reads the symbol	table on its own, but uses BFD to fix things up.  More of the	bit twiddlers are exported for @code{gas};	@code{coff_swap_aux_out}, @code{coff_swap_sym_out},	@code{coff_swap_lineno_out}, @code{coff_swap_reloc_out},	@code{coff_swap_filehdr_out}, @code{coff_swap_aouthdr_out},	@code{coff_swap_scnhdr_out}. @code{Gas} currently keeps track	of all the symbol table and reloc drudgery itself, thereby	saving the internal BFD overhead, but uses BFD to swap things	on the way out, making cross ports much safer.  Doing so also	allows BFD (and thus the linker) to use the same header files	as @code{gas}, which makes one avenue to disaster disappear. SUBSUBSECTION	Symbol reading 	The simple canonical form for symbols used by BFD is not rich	enough to keep all the information available in a coff symbol	table. The back end gets around this problem by keeping the original	symbol table around, "behind the scenes". 	When a symbol table is requested (through a call to	@code{bfd_canonicalize_symtab}), a request gets through to	@code{coff_get_normalized_symtab}. This reads the symbol table from	the coff file and swaps all the structures inside into the	internal form. It also fixes up all the pointers in the table	(represented in the file by offsets from the first symbol in	the table) into physical pointers to elements in the new	internal table. This involves some work since the meanings of	fields change depending upon context: a field that is a	pointer to another structure in the symbol table at one moment	may be the size in bytes of a structure at the next.  Another	pass is made over the table. All symbols which mark file names	(<<C_FILE>> symbols) are modified so that the internal	string points to the value in the auxent (the real filename)	rather than the normal text associated with the symbol	(@code{".file"}). 	At this time the symbol names are moved around. Coff stores	all symbols less than nine characters long physically	within the symbol table; longer strings are kept at the end of	the file in the string table. This pass moves all strings	into memory and replaces them with pointers to the strings. 	The symbol table is massaged once again, this time to create	the canonical table used by the BFD application. Each symbol	is inspected in turn, and a decision made (using the	@code{sclass} field) about the various flags to set in the	@code{asymbol}.  @xref{Symbols}. The generated canonical table	shares strings with the hidden internal symbol table. 	Any linenumbers are read from the coff file too, and attached	to the symbols which own the functions the linenumbers belong to. SUBSUBSECTION	Symbol writing 	Writing a symbol to a coff file which didn't come from a coff	file will lose any debugging information. The @code{asymbol}	structure remembers the BFD from which the symbol was taken, and on	output the back end makes sure that the same destination target as	source target is present. 	When the symbols have come from a coff file then all the	debugging information is preserved. 	Symbol tables are provided for writing to the back end in a	vector of pointers to pointers. This allows applications like	the linker to accumulate and output large symbol tables	without having to do too much byte copying. 	This function runs through the provided symbol table and	patches each symbol marked as a file place holder	(@code{C_FILE}) to point to the next file place holder in the	list. It also marks each @code{offset} field in the list with	the offset from the first symbol of the current symbol. 	Another function of this procedure is to turn the canonical	value form of BFD into the form used by coff. Internally, BFD	expects symbol values to be offsets from a section base; so a	symbol physically at 0x120, but in a section starting at	0x100, would have the value 0x20. Coff expects symbols to	contain their final value, so symbols have their values	changed at this point to reflect their sum with their owning	section.  This transformation uses the	<<output_section>> field of the @code{asymbol}'s	@code{asection} @xref{Sections}. 	o <<coff_mangle_symbols>> 	This routine runs though the provided symbol table and uses	the offsets generated by the previous pass and the pointers	generated when the symbol table was read in to create the	structured hierarchy required by coff. It changes each pointer	to a symbol into the index into the symbol table of the asymbol. 	o <<coff_write_symbols>> 	This routine runs through the symbol table and patches up the	symbols from their internal form into the coff way, calls the	bit twiddlers, and writes out the table to the file. */ /*INTERNAL_DEFINITION	coff_symbol_type DESCRIPTION	The hidden information for an <<asymbol>> is described in a	<<combined_entry_type>>: CODE_FRAGMENT..typedef struct coff_ptr_struct.{.  {* Remembers the offset from the first symbol in the file for.     this symbol. Generated by coff_renumber_symbols. *}.  unsigned int offset;..  {* Should the value of this symbol be renumbered.  Used for.     XCOFF C_BSTAT symbols.  Set by coff_slurp_symbol_table.  *}.  unsigned int fix_value : 1;..  {* Should the tag field of this symbol be renumbered..     Created by coff_pointerize_aux. *}.  unsigned int fix_tag : 1;..  {* Should the endidx field of this symbol be renumbered..     Created by coff_pointerize_aux. *}.  unsigned int fix_end : 1;..  {* Should the x_csect.x_scnlen field be renumbered..     Created by coff_pointerize_aux. *}.  unsigned int fix_scnlen : 1;..  {* Fix up an XCOFF C_BINCL/C_EINCL symbol.  The value is the.     index into the line number entries.  Set by coff_slurp_symbol_table.  *}.  unsigned int fix_line : 1;..  {* The container for the symbol structure as read and translated.     from the file. *}.  union.  {.    union internal_auxent auxent;.    struct internal_syment syment;.  } u;.} combined_entry_type;...{* Each canonical asymbol really looks like this: *}..typedef struct coff_symbol_struct.{.  {* The actual symbol which the rest of BFD works with *}.  asymbol symbol;..  {* A pointer to the hidden information for this symbol *}.  combined_entry_type *native;..  {* A pointer to the linenumber information for this symbol *}.  struct lineno_cache_entry *lineno;..  {* Have the line numbers been relocated yet ? *}.  bfd_boolean done_lineno;.} coff_symbol_type; */ #include "libiberty.h" #ifdef COFF_WITH_PE#include "peicode.h"#else#include "coffswap.h"#endif #define STRING_SIZE_SIZE 4 #define DOT_DEBUG	".debug"#define DOT_ZDEBUG	".zdebug"#define GNU_LINKONCE_WI ".gnu.linkonce.wi."#define GNU_LINKONCE_WT ".gnu.linkonce.wt."#define DOT_RELOC	".reloc" #if defined (COFF_LONG_SECTION_NAMES)/* Needed to expand the inputs to BLANKOR1TOODD.  */#define COFFLONGSECTIONCATHELPER(x,y)    x ## y/* If the input macro Y is blank or '1', return an odd number; if it is   '0', return an even number.  Result undefined in all other cases.  */#define BLANKOR1TOODD(y)                 COFFLONGSECTIONCATHELPER(1,y)/* Defined to numerical 0 or 1 according to whether generation of long   section names is disabled or enabled by default.  */#define COFF_ENABLE_LONG_SECTION_NAMES   (BLANKOR1TOODD(COFF_LONG_SECTION_NAMES) & 1)/* Where long section names are supported, we allow them to be enabled   and disabled at runtime, so select an appropriate hook function for   _bfd_coff_set_long_section_names.  */#define COFF_LONG_SECTION_NAMES_SETTER   bfd_coff_set_long_section_names_allowed#else /* !defined (COFF_LONG_SECTION_NAMES) *//* If long section names are not supported, this stub disallows any   attempt to enable them at run-time.  */#define COFF_LONG_SECTION_NAMES_SETTER   bfd_coff_set_long_section_names_disallowed#endif /* defined (COFF_LONG_SECTION_NAMES) */ /* Define a macro that can be used to initialise both the fields relating   to long section names in the backend data struct simultaneously.  */#if COFF_ENABLE_LONG_SECTION_NAMES#define COFF_DEFAULT_LONG_SECTION_NAMES  (TRUE), COFF_LONG_SECTION_NAMES_SETTER#else /* !COFF_ENABLE_LONG_SECTION_NAMES */#define COFF_DEFAULT_LONG_SECTION_NAMES  (FALSE), COFF_LONG_SECTION_NAMES_SETTER#endif /* COFF_ENABLE_LONG_SECTION_NAMES */ #if defined (COFF_LONG_SECTION_NAMES)static bfd_boolean bfd_coff_set_long_section_names_allowed  (bfd *, int);#else /* !defined (COFF_LONG_SECTION_NAMES) */static bfd_boolean bfd_coff_set_long_section_names_disallowed  (bfd *, int);#endif /* defined (COFF_LONG_SECTION_NAMES) */static long sec_to_styp_flags  (const char *, flagword);static bfd_boolean styp_to_sec_flags  (bfd *, void *, const char *, asection *, flagword *);static bfd_boolean coff_bad_format_hook  (bfd *, void *);static void coff_set_custom_section_alignment  (bfd *, asection *, const struct coff_section_alignment_entry *,   const unsigned int);static bfd_boolean coff_new_section_hook  (bfd *, asection *);static bfd_boolean coff_set_arch_mach_hook  (bfd *, void *);static bfd_boolean coff_write_relocs  (bfd *, int);static bfd_boolean coff_set_flags  (bfd *, unsigned int *, unsigned short *);static bfd_boolean coff_set_arch_mach  (bfd *, enum bfd_architecture, unsigned long) ATTRIBUTE_UNUSED;static bfd_boolean coff_compute_section_file_positions  (bfd *);static bfd_boolean coff_write_object_contents  (bfd *) ATTRIBUTE_UNUSED;static bfd_boolean coff_set_section_contents  (bfd *, asection *, const void *, file_ptr, bfd_size_type);static void * buy_and_read  (bfd *, file_ptr, bfd_size_type);static bfd_boolean coff_slurp_line_table  (bfd *, asection *);static bfd_boolean coff_slurp_symbol_table  (bfd *);static enum coff_symbol_classification coff_classify_symbol  (bfd *, struct internal_syment *);static bfd_boolean coff_slurp_reloc_table  (bfd *, asection *, asymbol **);static long coff_canonicalize_reloc  (bfd *, asection *, arelent **, asymbol **);#ifndef coff_mkobject_hookstatic void * coff_mkobject_hook  (bfd *, void *,  void *);#endif#ifdef COFF_WITH_PEstatic flagword handle_COMDAT  (bfd *, flagword, void *, const char *, asection *);#endif#ifdef COFF_IMAGE_WITH_PEstatic bfd_boolean coff_read_word  (bfd *, unsigned int *);static unsigned int coff_compute_checksum  (bfd *);static bfd_boolean coff_apply_checksum  (bfd *);#endif#ifdef TICOFFstatic bfd_boolean ticoff0_bad_format_hook  (bfd *, void * );static bfd_boolean ticoff1_bad_format_hook  (bfd *, void * );#endif/* void warning(); */ #if defined (COFF_LONG_SECTION_NAMES)static bfd_booleanbfd_coff_set_long_section_names_allowed (bfd *abfd, int enable){  coff_backend_info (abfd)->_bfd_coff_long_section_names = enable;  return TRUE;}#else /* !defined (COFF_LONG_SECTION_NAMES) */static bfd_booleanbfd_coff_set_long_section_names_disallowed (bfd *abfd, int enable){  (void) abfd;  (void) enable;  return FALSE;}#endif /* defined (COFF_LONG_SECTION_NAMES) */ /* Return a word with STYP_* (scnhdr.s_flags) flags set to represent   the incoming SEC_* flags.  The inverse of this function is   styp_to_sec_flags().  NOTE: If you add to/change this routine, you   should probably mirror the changes in styp_to_sec_flags().  */ #ifndef COFF_WITH_PE /* Macros for setting debugging flags.  */ #ifdef STYP_DEBUG

Lines 1–500 of 5846. Load more