Subversion Repositories Kolibri OS

/* Generic symbol-table support for the BFD library.

   Copyright (C) 1990-2015 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.  */

/*

SECTION

	Symbols

	BFD tries to maintain as much symbol information as it can when

	it moves information from file to file. BFD passes information

	to applications though the <> structure. When the

	application requests the symbol table, BFD reads the table in

	the native form and translates parts of it into the internal

	format. To maintain more than the information passed to

	applications, some targets keep some information ``behind the

	scenes'' in a structure only the particular back end knows

	about. For example, the coff back end keeps the original

	symbol table structure as well as the canonical structure when

	a BFD is read in. On output, the coff back end can reconstruct

	the output symbol table so that no information is lost, even

	information unique to coff which BFD doesn't know or

	understand. If a coff symbol table were read, but were written

	through an a.out back end, all the coff specific information

	would be lost. The symbol table of a BFD

	is not necessarily read in until a canonicalize request is

	made. Then the BFD back end fills in a table provided by the

	application with pointers to the canonical information.  To

	output symbols, the application provides BFD with a table of

	pointers to pointers to <>s. This allows applications

	like the linker to output a symbol as it was read, since the ``behind

	the scenes'' information will be still available.

@menu

@* Reading Symbols::

@* Writing Symbols::

@* Mini Symbols::

@* typedef asymbol::

@* symbol handling functions::

@end menu

INODE

Reading Symbols, Writing Symbols, Symbols, Symbols

SUBSECTION

	Reading symbols

	There are two stages to reading a symbol table from a BFD:

	allocating storage, and the actual reading process. This is an

	excerpt from an application which reads the symbol table:

|	  long storage_needed;

|	  asymbol **symbol_table;

|	  long number_of_symbols;

|	  long i;

|

|	  storage_needed = bfd_get_symtab_upper_bound (abfd);

|

|         if (storage_needed < 0)

|           FAIL

|

|	  if (storage_needed == 0)

|	    return;

|

|	  symbol_table = xmalloc (storage_needed);

|	    ...

|	  number_of_symbols =

|	     bfd_canonicalize_symtab (abfd, symbol_table);

|

|         if (number_of_symbols < 0)

|           FAIL

|

|	  for (i = 0; i < number_of_symbols; i++)

|	    process_symbol (symbol_table[i]);

	All storage for the symbols themselves is in an objalloc

	connected to the BFD; it is freed when the BFD is closed.

INODE

Writing Symbols, Mini Symbols, Reading Symbols, Symbols

SUBSECTION

	Writing symbols

	Writing of a symbol table is automatic when a BFD open for

	writing is closed. The application attaches a vector of

	pointers to pointers to symbols to the BFD being written, and

	fills in the symbol count. The close and cleanup code reads

	through the table provided and performs all the necessary

	operations. The BFD output code must always be provided with an

	``owned'' symbol: one which has come from another BFD, or one

	which has been created using <>.  Here is an

	example showing the creation of a symbol table with only one element:

|	#include "sysdep.h"

|	#include "bfd.h"

|	int main (void)

|	{

|	  bfd *abfd;

|	  asymbol *ptrs[2];

|	  asymbol *new;

|

|	  abfd = bfd_openw ("foo","a.out-sunos-big");

|	  bfd_set_format (abfd, bfd_object);

|	  new = bfd_make_empty_symbol (abfd);

|	  new->name = "dummy_symbol";

|	  new->section = bfd_make_section_old_way (abfd, ".text");

|	  new->flags = BSF_GLOBAL;

|	  new->value = 0x12345;

|

|	  ptrs[0] = new;

|	  ptrs[1] = 0;

|

|	  bfd_set_symtab (abfd, ptrs, 1);

|	  bfd_close (abfd);

|	  return 0;

|	}

|

|	./makesym

|	nm foo

|	00012345 A dummy_symbol

	Many formats cannot represent arbitrary symbol information; for

 	instance, the <> object format does not allow an

	arbitrary number of sections. A symbol pointing to a section

	which is not one  of <<.text>>, <<.data>> or <<.bss>> cannot

	be described.

INODE

Mini Symbols, typedef asymbol, Writing Symbols, Symbols

SUBSECTION

	Mini Symbols

	Mini symbols provide read-only access to the symbol table.

	They use less memory space, but require more time to access.

	They can be useful for tools like nm or objdump, which may

	have to handle symbol tables of extremely large executables.

	The <> function will read the symbols

	into memory in an internal form.  It will return a <>

	pointer to a block of memory, a symbol count, and the size of

	each symbol.  The pointer is allocated using <>, and

	should be freed by the caller when it is no longer needed.

	The function <> will take a pointer

	to a minisymbol, and a pointer to a structure returned by

	<>, and return a <> structure.

	The return value may or may not be the same as the value from

	<> which was passed in.

*/

/*

DOCDD

INODE

typedef asymbol, symbol handling functions, Mini Symbols, Symbols

*/

/*

SUBSECTION

	typedef asymbol

	An <> has the form:

*/

/*

CODE_FRAGMENT

.

.typedef struct bfd_symbol

.{

.  {* A pointer to the BFD which owns the symbol. This information

.     is necessary so that a back end can work out what additional

.     information (invisible to the application writer) is carried

.     with the symbol.

.

.     This field is *almost* redundant, since you can use section->owner

.     instead, except that some symbols point to the global sections

.     bfd_{abs,com,und}_section.  This could be fixed by making

.     these globals be per-bfd (or per-target-flavor).  FIXME.  *}

.  struct bfd *the_bfd; {* Use bfd_asymbol_bfd(sym) to access this field.  *}

.

.  {* The text of the symbol. The name is left alone, and not copied; the

.     application may not alter it.  *}

.  const char *name;

.

.  {* The value of the symbol.  This really should be a union of a

.     numeric value with a pointer, since some flags indicate that

.     a pointer to another symbol is stored here.  *}

.  symvalue value;

.

.  {* Attributes of a symbol.  *}

.#define BSF_NO_FLAGS    	0x00

.

.  {* The symbol has local scope; <> in <>. The value

.     is the offset into the section of the data.  *}

.#define BSF_LOCAL		(1 << 0)

.

.  {* The symbol has global scope; initialized data in <>. The

.     value is the offset into the section of the data.  *}

.#define BSF_GLOBAL		(1 << 1)

.

.  {* The symbol has global scope and is exported. The value is

.     the offset into the section of the data.  *}

.#define BSF_EXPORT	BSF_GLOBAL {* No real difference.  *}

.

.  {* A normal C symbol would be one of:

.     <>, <>,  <> or

.     <>.  *}

.

.  {* The symbol is a debugging record. The value has an arbitrary

.     meaning, unless BSF_DEBUGGING_RELOC is also set.  *}

.#define BSF_DEBUGGING		(1 << 2)

.

.  {* The symbol denotes a function entry point.  Used in ELF,

.     perhaps others someday.  *}

.#define BSF_FUNCTION		(1 << 3)

.

.  {* Used by the linker.  *}

.#define BSF_KEEP		(1 << 5)

.#define BSF_KEEP_G		(1 << 6)

.

.  {* A weak global symbol, overridable without warnings by

.     a regular global symbol of the same name.  *}

.#define BSF_WEAK		(1 << 7)

.

.  {* This symbol was created to point to a section, e.g. ELF's

.     STT_SECTION symbols.  *}

.#define BSF_SECTION_SYM	(1 << 8)

.

.  {* The symbol used to be a common symbol, but now it is

.     allocated.  *}

.#define BSF_OLD_COMMON		(1 << 9)

.

.  {* In some files the type of a symbol sometimes alters its

.     location in an output file - ie in coff a <> symbol

.     which is also <> symbol appears where it was

.     declared and not at the end of a section.  This bit is set

.     by the target BFD part to convey this information.  *}

.#define BSF_NOT_AT_END		(1 << 10)

.

.  {* Signal that the symbol is the label of constructor section.  *}

.#define BSF_CONSTRUCTOR	(1 << 11)

.

.  {* Signal that the symbol is a warning symbol.  The name is a

.     warning.  The name of the next symbol is the one to warn about;

.     if a reference is made to a symbol with the same name as the next

.     symbol, a warning is issued by the linker.  *}

.#define BSF_WARNING		(1 << 12)

.

.  {* Signal that the symbol is indirect.  This symbol is an indirect

.     pointer to the symbol with the same name as the next symbol.  *}

.#define BSF_INDIRECT		(1 << 13)

.

.  {* BSF_FILE marks symbols that contain a file name.  This is used

.     for ELF STT_FILE symbols.  *}

.#define BSF_FILE		(1 << 14)

.

.  {* Symbol is from dynamic linking information.  *}

.#define BSF_DYNAMIC		(1 << 15)

.

.  {* The symbol denotes a data object.  Used in ELF, and perhaps

.     others someday.  *}

.#define BSF_OBJECT		(1 << 16)

.

.  {* This symbol is a debugging symbol.  The value is the offset

.     into the section of the data.  BSF_DEBUGGING should be set

.     as well.  *}

.#define BSF_DEBUGGING_RELOC	(1 << 17)

.

.  {* This symbol is thread local.  Used in ELF.  *}

.#define BSF_THREAD_LOCAL	(1 << 18)

.

.  {* This symbol represents a complex relocation expression,

.     with the expression tree serialized in the symbol name.  *}

.#define BSF_RELC		(1 << 19)

.

.  {* This symbol represents a signed complex relocation expression,

.     with the expression tree serialized in the symbol name.  *}

.#define BSF_SRELC		(1 << 20)

.

.  {* This symbol was created by bfd_get_synthetic_symtab.  *}

.#define BSF_SYNTHETIC		(1 << 21)

.

.  {* This symbol is an indirect code object.  Unrelated to BSF_INDIRECT.

.     The dynamic linker will compute the value of this symbol by

.     calling the function that it points to.  BSF_FUNCTION must

.     also be also set.  *}

.#define BSF_GNU_INDIRECT_FUNCTION (1 << 22)

.  {* This symbol is a globally unique data object.  The dynamic linker

.     will make sure that in the entire process there is just one symbol

.     with this name and type in use.  BSF_OBJECT must also be set.  *}

.#define BSF_GNU_UNIQUE		(1 << 23)

.

.  flagword flags;

.

.  {* A pointer to the section to which this symbol is

.     relative.  This will always be non NULL, there are special

.     sections for undefined and absolute symbols.  *}

.  struct bfd_section *section;

.

.  {* Back end special data.  *}

.  union

.    {

.      void *p;

.      bfd_vma i;

.    }

.  udata;

.}

.asymbol;

.

*/

#include "sysdep.h"

#include "bfd.h"

#include "libbfd.h"

#include "safe-ctype.h"

#include "bfdlink.h"

#include "aout/stab_gnu.h"

/*

DOCDD

INODE

symbol handling functions,  , typedef asymbol, Symbols

SUBSECTION

	Symbol handling functions

*/

/*

FUNCTION

	bfd_get_symtab_upper_bound

DESCRIPTION

	Return the number of bytes required to store a vector of pointers

	to <> for all the symbols in the BFD @var{abfd},

	including a terminal NULL pointer. If there are no symbols in

	the BFD, then return 0.  If an error occurs, return -1.

.#define bfd_get_symtab_upper_bound(abfd) \

.     BFD_SEND (abfd, _bfd_get_symtab_upper_bound, (abfd))

.

*/

/*

FUNCTION

	bfd_is_local_label

SYNOPSIS

        bfd_boolean bfd_is_local_label (bfd *abfd, asymbol *sym);

DESCRIPTION

	Return TRUE if the given symbol @var{sym} in the BFD @var{abfd} is

	a compiler generated local label, else return FALSE.

*/

bfd_boolean

bfd_is_local_label (bfd *abfd, asymbol *sym)

{

  /* The BSF_SECTION_SYM check is needed for IA-64, where every label that

     starts with '.' is local.  This would accidentally catch section names

     if we didn't reject them here.  */

  if ((sym->flags & (BSF_GLOBAL | BSF_WEAK | BSF_FILE | BSF_SECTION_SYM)) != 0)

    return FALSE;

  if (sym->name == NULL)

    return FALSE;

  return bfd_is_local_label_name (abfd, sym->name);

}

/*

FUNCTION

	bfd_is_local_label_name

SYNOPSIS

        bfd_boolean bfd_is_local_label_name (bfd *abfd, const char *name);

DESCRIPTION

	Return TRUE if a symbol with the name @var{name} in the BFD

	@var{abfd} is a compiler generated local label, else return

	FALSE.  This just checks whether the name has the form of a

	local label.

.#define bfd_is_local_label_name(abfd, name) \

.  BFD_SEND (abfd, _bfd_is_local_label_name, (abfd, name))

.

*/

/*

FUNCTION

	bfd_is_target_special_symbol

SYNOPSIS

        bfd_boolean bfd_is_target_special_symbol (bfd *abfd, asymbol *sym);

DESCRIPTION

	Return TRUE iff a symbol @var{sym} in the BFD @var{abfd} is something

	special to the particular target represented by the BFD.  Such symbols

	should normally not be mentioned to the user.

.#define bfd_is_target_special_symbol(abfd, sym) \

.  BFD_SEND (abfd, _bfd_is_target_special_symbol, (abfd, sym))

.

*/

/*

FUNCTION

	bfd_canonicalize_symtab

DESCRIPTION

	Read the symbols from the BFD @var{abfd}, and fills in

	the vector @var{location} with pointers to the symbols and

	a trailing NULL.

	Return the actual number of symbol pointers, not

	including the NULL.

.#define bfd_canonicalize_symtab(abfd, location) \

.  BFD_SEND (abfd, _bfd_canonicalize_symtab, (abfd, location))

.

*/

/*

FUNCTION

	bfd_set_symtab

SYNOPSIS

	bfd_boolean bfd_set_symtab

	  (bfd *abfd, asymbol **location, unsigned int count);

DESCRIPTION

	Arrange that when the output BFD @var{abfd} is closed,

	the table @var{location} of @var{count} pointers to symbols

	will be written.

*/

bfd_boolean

bfd_set_symtab (bfd *abfd, asymbol **location, unsigned int symcount)

{

  if (abfd->format != bfd_object || bfd_read_p (abfd))

    {

      bfd_set_error (bfd_error_invalid_operation);

      return FALSE;

    }

  bfd_get_outsymbols (abfd) = location;

  bfd_get_symcount (abfd) = symcount;

  return TRUE;

}

/*

FUNCTION

	bfd_print_symbol_vandf

SYNOPSIS

	void bfd_print_symbol_vandf (bfd *abfd, void *file, asymbol *symbol);

DESCRIPTION

	Print the value and flags of the @var{symbol} supplied to the

	stream @var{file}.

*/

void

bfd_print_symbol_vandf (bfd *abfd, void *arg, asymbol *symbol)

{

  FILE *file = (FILE *) arg;

  flagword type = symbol->flags;

  if (symbol->section != NULL)

    bfd_fprintf_vma (abfd, file, symbol->value + symbol->section->vma);

  else

    bfd_fprintf_vma (abfd, file, symbol->value);

  /* This presumes that a symbol can not be both BSF_DEBUGGING and

     BSF_DYNAMIC, nor more than one of BSF_FUNCTION, BSF_FILE, and

     BSF_OBJECT.  */

  fprintf (file, " %c%c%c%c%c%c%c",

	   ((type & BSF_LOCAL)

	    ? (type & BSF_GLOBAL) ? '!' : 'l'

	    : (type & BSF_GLOBAL) ? 'g'

	    : (type & BSF_GNU_UNIQUE) ? 'u' : ' '),

	   (type & BSF_WEAK) ? 'w' : ' ',

	   (type & BSF_CONSTRUCTOR) ? 'C' : ' ',

	   (type & BSF_WARNING) ? 'W' : ' ',

	   (type & BSF_INDIRECT) ? 'I' : (type & BSF_GNU_INDIRECT_FUNCTION) ? 'i' : ' ',

	   (type & BSF_DEBUGGING) ? 'd' : (type & BSF_DYNAMIC) ? 'D' : ' ',

	   ((type & BSF_FUNCTION)

	    ? 'F'

	    : ((type & BSF_FILE)

	       ? 'f'

	       : ((type & BSF_OBJECT) ? 'O' : ' '))));

}

/*

FUNCTION

	bfd_make_empty_symbol

DESCRIPTION

	Create a new <> structure for the BFD @var{abfd}

	and return a pointer to it.

	This routine is necessary because each back end has private

	information surrounding the <>. Building your own

	<> and pointing to it will not create the private

	information, and will cause problems later on.

.#define bfd_make_empty_symbol(abfd) \

.  BFD_SEND (abfd, _bfd_make_empty_symbol, (abfd))

.

*/

/*

FUNCTION

	_bfd_generic_make_empty_symbol

SYNOPSIS

	asymbol *_bfd_generic_make_empty_symbol (bfd *);

DESCRIPTION

	Create a new <> structure for the BFD @var{abfd}

	and return a pointer to it.  Used by core file routines,

	binary back-end and anywhere else where no private info

	is needed.

*/

asymbol *

_bfd_generic_make_empty_symbol (bfd *abfd)

{

  bfd_size_type amt = sizeof (asymbol);

  asymbol *new_symbol = (asymbol *) bfd_zalloc (abfd, amt);

  if (new_symbol)

    new_symbol->the_bfd = abfd;

  return new_symbol;

}

/*

FUNCTION

	bfd_make_debug_symbol

DESCRIPTION

	Create a new <> structure for the BFD @var{abfd},

	to be used as a debugging symbol.  Further details of its use have

	yet to be worked out.

.#define bfd_make_debug_symbol(abfd,ptr,size) \

.  BFD_SEND (abfd, _bfd_make_debug_symbol, (abfd, ptr, size))

.

*/

struct section_to_type

{

  const char *section;

  char type;

};

/* Map section names to POSIX/BSD single-character symbol types.

   This table is probably incomplete.  It is sorted for convenience of

   adding entries.  Since it is so short, a linear search is used.  */

static const struct section_to_type stt[] =

{

  {".bss", 'b'},

  {"code", 't'},		/* MRI .text */

  {".data", 'd'},

  {"*DEBUG*", 'N'},

  {".debug", 'N'},              /* MSVC's .debug (non-standard debug syms) */

  {".drectve", 'i'},            /* MSVC's .drective section */

  {".edata", 'e'},              /* MSVC's .edata (export) section */

  {".fini", 't'},		/* ELF fini section */

  {".idata", 'i'},              /* MSVC's .idata (import) section */

  {".init", 't'},		/* ELF init section */

  {".pdata", 'p'},              /* MSVC's .pdata (stack unwind) section */

  {".rdata", 'r'},		/* Read only data.  */

  {".rodata", 'r'},		/* Read only data.  */

  {".sbss", 's'},		/* Small BSS (uninitialized data).  */

  {".scommon", 'c'},		/* Small common.  */

  {".sdata", 'g'},		/* Small initialized data.  */

  {".text", 't'},

  {"vars", 'd'},		/* MRI .data */

  {"zerovars", 'b'},		/* MRI .bss */

  {0, 0}

};

/* Return the single-character symbol type corresponding to

   section S, or '?' for an unknown COFF section.

   Check for any leading string which matches, so .text5 returns

   't' as well as .text */

static char

coff_section_type (const char *s)

{

  const struct section_to_type *t;

  for (t = &stt[0]; t->section; t++)

    if (!strncmp (s, t->section, strlen (t->section)))

      return t->type;

  return '?';

}

/* Return the single-character symbol type corresponding to section

   SECTION, or '?' for an unknown section.  This uses section flags to

   identify sections.

   FIXME These types are unhandled: c, i, e, p.  If we handled these also,

   we could perhaps obsolete coff_section_type.  */

static char

decode_section_type (const struct bfd_section *section)

{

  if (section->flags & SEC_CODE)

    return 't';

  if (section->flags & SEC_DATA)

    {

      if (section->flags & SEC_READONLY)

	return 'r';

      else if (section->flags & SEC_SMALL_DATA)

	return 'g';

      else

	return 'd';

    }

  if ((section->flags & SEC_HAS_CONTENTS) == 0)

    {

      if (section->flags & SEC_SMALL_DATA)

	return 's';

      else

	return 'b';

    }

  if (section->flags & SEC_DEBUGGING)

    return 'N';

  if ((section->flags & SEC_HAS_CONTENTS) && (section->flags & SEC_READONLY))

    return 'n';

  return '?';

}

/*

FUNCTION

	bfd_decode_symclass

DESCRIPTION

	Return a character corresponding to the symbol

	class of @var{symbol}, or '?' for an unknown class.

SYNOPSIS

	int bfd_decode_symclass (asymbol *symbol);

*/

int

bfd_decode_symclass (asymbol *symbol)

{

  char c;

  if (symbol->section && bfd_is_com_section (symbol->section))

    return 'C';

  if (bfd_is_und_section (symbol->section))

    {

      if (symbol->flags & BSF_WEAK)

	{

	  /* If weak, determine if it's specifically an object

	     or non-object weak.  */

	  if (symbol->flags & BSF_OBJECT)

	    return 'v';

	  else

	    return 'w';

	}

      else

	return 'U';

    }

  if (bfd_is_ind_section (symbol->section))

    return 'I';

  if (symbol->flags & BSF_GNU_INDIRECT_FUNCTION)

    return 'i';

  if (symbol->flags & BSF_WEAK)

    {

      /* If weak, determine if it's specifically an object

	 or non-object weak.  */

      if (symbol->flags & BSF_OBJECT)

	return 'V';

      else

	return 'W';

    }

  if (symbol->flags & BSF_GNU_UNIQUE)

    return 'u';

  if (!(symbol->flags & (BSF_GLOBAL | BSF_LOCAL)))

    return '?';

  if (bfd_is_abs_section (symbol->section))

    c = 'a';

  else if (symbol->section)

    {

      c = coff_section_type (symbol->section->name);

      if (c == '?')

	c = decode_section_type (symbol->section);

    }

  else

    return '?';

  if (symbol->flags & BSF_GLOBAL)

    c = TOUPPER (c);

  return c;

  /* We don't have to handle these cases just yet, but we will soon:

     N_SETV: 'v';

     N_SETA: 'l';

     N_SETT: 'x';

     N_SETD: 'z';

     N_SETB: 's';

     N_INDR: 'i';

     */

}

/*

FUNCTION

	bfd_is_undefined_symclass

DESCRIPTION

	Returns non-zero if the class symbol returned by

	bfd_decode_symclass represents an undefined symbol.

	Returns zero otherwise.

SYNOPSIS

	bfd_boolean bfd_is_undefined_symclass (int symclass);

*/

bfd_boolean

bfd_is_undefined_symclass (int symclass)

{

  return symclass == 'U' || symclass == 'w' || symclass == 'v';

}

/*

FUNCTION

	bfd_symbol_info

DESCRIPTION

	Fill in the basic info about symbol that nm needs.

	Additional info may be added by the back-ends after

	calling this function.

SYNOPSIS

	void bfd_symbol_info (asymbol *symbol, symbol_info *ret);

*/

void

bfd_symbol_info (asymbol *symbol, symbol_info *ret)

{

  ret->type = bfd_decode_symclass (symbol);

  if (bfd_is_undefined_symclass (ret->type))

    ret->value = 0;

  else

    ret->value = symbol->value + symbol->section->vma;

  ret->name = symbol->name;

}

/*

FUNCTION

	bfd_copy_private_symbol_data

SYNOPSIS

	bfd_boolean bfd_copy_private_symbol_data

	  (bfd *ibfd, asymbol *isym, bfd *obfd, asymbol *osym);

DESCRIPTION

	Copy private symbol information from @var{isym} in the BFD

	@var{ibfd} to the symbol @var{osym} in the BFD @var{obfd}.

	Return <> on success, <> on error.  Possible error

	returns are:

	o <> -

	Not enough memory exists to create private data for @var{osec}.

.#define bfd_copy_private_symbol_data(ibfd, isymbol, obfd, osymbol) \

.  BFD_SEND (obfd, _bfd_copy_private_symbol_data, \

.            (ibfd, isymbol, obfd, osymbol))

.

*/

/* The generic version of the function which returns mini symbols.

   This is used when the backend does not provide a more efficient

   version.  It just uses BFD asymbol structures as mini symbols.  */

long

_bfd_generic_read_minisymbols (bfd *abfd,

			       bfd_boolean dynamic,

			       void **minisymsp,

			       unsigned int *sizep)

{

  long storage;

  asymbol **syms = NULL;

  long symcount;

  if (dynamic)

    storage = bfd_get_dynamic_symtab_upper_bound (abfd);

  else

    storage = bfd_get_symtab_upper_bound (abfd);

  if (storage < 0)

    goto error_return;

  if (storage == 0)

    return 0;

  syms = (asymbol **) bfd_malloc (storage);

  if (syms == NULL)

    goto error_return;

  if (dynamic)

    symcount = bfd_canonicalize_dynamic_symtab (abfd, syms);

  else

    symcount = bfd_canonicalize_symtab (abfd, syms);

  if (symcount < 0)

    goto error_return;

  *minisymsp = syms;

  *sizep = sizeof (asymbol *);

  return symcount;

 error_return:

  bfd_set_error (bfd_error_no_symbols);

  if (syms != NULL)

    free (syms);

  return -1;

}

/* The generic version of the function which converts a minisymbol to

   an asymbol.  We don't worry about the sym argument we are passed;

   we just return the asymbol the minisymbol points to.  */

asymbol *

_bfd_generic_minisymbol_to_symbol (bfd *abfd ATTRIBUTE_UNUSED,

				   bfd_boolean dynamic ATTRIBUTE_UNUSED,

				   const void *minisym,

				   asymbol *sym ATTRIBUTE_UNUSED)

{

  return *(asymbol **) minisym;

}

/* Look through stabs debugging information in .stab and .stabstr

   sections to find the source file and line closest to a desired

   location.  This is used by COFF and ELF targets.  It sets *pfound

   to TRUE if it finds some information.  The *pinfo field is used to

   pass cached information in and out of this routine; this first time

   the routine is called for a BFD, *pinfo should be NULL.  The value

   placed in *pinfo should be saved with the BFD, and passed back each

   time this function is called.  */

/* We use a cache by default.  */

#define ENABLE_CACHING

/* We keep an array of indexentry structures to record where in the

   stabs section we should look to find line number information for a

   particular address.  */

struct indexentry

{

  bfd_vma val;

  bfd_byte *stab;

  bfd_byte *str;

  char *directory_name;

  char *file_name;

  char *function_name;

};

/* Compare two indexentry structures.  This is called via qsort.  */

static int

cmpindexentry (const void *a, const void *b)

{

  const struct indexentry *contestantA = (const struct indexentry *) a;

  const struct indexentry *contestantB = (const struct indexentry *) b;

  if (contestantA->val < contestantB->val)

    return -1;

  else if (contestantA->val > contestantB->val)

    return 1;

  else

    return 0;

}

/* A pointer to this structure is stored in *pinfo.  */

struct stab_find_info

{

  /* The .stab section.  */

  asection *stabsec;

  /* The .stabstr section.  */

  asection *strsec;

  /* The contents of the .stab section.  */

  bfd_byte *stabs;

  /* The contents of the .stabstr section.  */

  bfd_byte *strs;

  /* A table that indexes stabs by memory address.  */

  struct indexentry *indextable;

  /* The number of entries in indextable.  */

  int indextablesize;

#ifdef ENABLE_CACHING

  /* Cached values to restart quickly.  */

  struct indexentry *cached_indexentry;

  bfd_vma cached_offset;

  bfd_byte *cached_stab;

  char *cached_file_name;

#endif

  /* Saved ptr to malloc'ed filename.  */

  char *filename;

};

bfd_boolean

_bfd_stab_section_find_nearest_line (bfd *abfd,

				     asymbol **symbols,

				     asection *section,

				     bfd_vma offset,

				     bfd_boolean *pfound,

				     const char **pfilename,

				     const char **pfnname,

				     unsigned int *pline,

				     void **pinfo)

{

  struct stab_find_info *info;

  bfd_size_type stabsize, strsize;

  bfd_byte *stab, *str;

  bfd_byte *nul_fun, *nul_str;

  bfd_size_type stroff;

  struct indexentry *indexentry;

  char *file_name;

  char *directory_name;

  bfd_boolean saw_line, saw_func;

  *pfound = FALSE;

  *pfilename = bfd_get_filename (abfd);

  *pfnname = NULL;

  *pline = 0;

  /* Stabs entries use a 12 byte format:

       4 byte string table index

       1 byte stab type

       1 byte stab other field

       2 byte stab desc field

       4 byte stab value

     FIXME: This will have to change for a 64 bit object format.

     The stabs symbols are divided into compilation units.  For the

     first entry in each unit, the type of 0, the value is the length

     of the string table for this unit, and the desc field is the

     number of stabs symbols for this unit.  */

#define STRDXOFF (0)

#define TYPEOFF (4)

#define OTHEROFF (5)

#define DESCOFF (6)

#define VALOFF (8)

#define STABSIZE (12)

  info = (struct stab_find_info *) *pinfo;

  if (info != NULL)

    {

      if (info->stabsec == NULL || info->strsec == NULL)

	{

	  /* No stabs debugging information.  */

	  return TRUE;

	}

      stabsize = (info->stabsec->rawsize

		  ? info->stabsec->rawsize

		  : info->stabsec->size);

      strsize = (info->strsec->rawsize

		 ? info->strsec->rawsize

		 : info->strsec->size);

    }

  else

    {

      long reloc_size, reloc_count;

      arelent **reloc_vector;

      int i;

      char *function_name;

      bfd_size_type amt = sizeof *info;

      info = (struct stab_find_info *) bfd_zalloc (abfd, amt);

      if (info == NULL)

	return FALSE;

      /* FIXME: When using the linker --split-by-file or

	 --split-by-reloc options, it is possible for the .stab and

	 .stabstr sections to be split.  We should handle that.  */

      info->stabsec = bfd_get_section_by_name (abfd, ".stab");

      info->strsec = bfd_get_section_by_name (abfd, ".stabstr");

      if (info->stabsec == NULL || info->strsec == NULL)

	{

	  /* Try SOM section names.  */

	  info->stabsec = bfd_get_section_by_name (abfd, "$GDB_SYMBOLS$");

	  info->strsec  = bfd_get_section_by_name (abfd, "$GDB_STRINGS$");

	  if (info->stabsec == NULL || info->strsec == NULL)

	    {

	      /* No stabs debugging information.  Set *pinfo so that we

		 can return quickly in the info != NULL case above.  */

	      *pinfo = info;

	      return TRUE;

	    }

	}

      stabsize = (info->stabsec->rawsize

		  ? info->stabsec->rawsize

		  : info->stabsec->size);

      stabsize = (stabsize / STABSIZE) * STABSIZE;

      strsize = (info->strsec->rawsize

		 ? info->strsec->rawsize

		 : info->strsec->size);

      info->stabs = (bfd_byte *) bfd_alloc (abfd, stabsize);

      info->strs = (bfd_byte *) bfd_alloc (abfd, strsize);

      if (info->stabs == NULL || info->strs == NULL)

	return FALSE;

      if (! bfd_get_section_contents (abfd, info->stabsec, info->stabs,

				      0, stabsize)

	  || ! bfd_get_section_contents (abfd, info->strsec, info->strs,

					 0, strsize))

	return FALSE;

      /* If this is a relocatable object file, we have to relocate

	 the entries in .stab.  This should always be simple 32 bit

	 relocations against symbols defined in this object file, so

	 this should be no big deal.  */

      reloc_size = bfd_get_reloc_upper_bound (abfd, info->stabsec);

      if (reloc_size < 0)

	return FALSE;

      reloc_vector = (arelent **) bfd_malloc (reloc_size);

      if (reloc_vector == NULL && reloc_size != 0)

	return FALSE;

      reloc_count = bfd_canonicalize_reloc (abfd, info->stabsec, reloc_vector,

					    symbols);

      if (reloc_count < 0)

	{

	  if (reloc_vector != NULL)

	    free (reloc_vector);

	  return FALSE;

	}

      if (reloc_count > 0)

	{

	  arelent **pr;

	  for (pr = reloc_vector; *pr != NULL; pr++)

	    {

	      arelent *r;

	      unsigned long val;

	      asymbol *sym;

	      r = *pr;

	      /* Ignore R_*_NONE relocs.  */

	      if (r->howto->dst_mask == 0)

		continue;

	      if (r->howto->rightshift != 0

		  || r->howto->size != 2

		  || r->howto->bitsize != 32

		  || r->howto->pc_relative

		  || r->howto->bitpos != 0

		  || r->howto->dst_mask != 0xffffffff)

		{

		  (*_bfd_error_handler)

		    (_("Unsupported .stab relocation"));

		  bfd_set_error (bfd_error_invalid_operation);

		  if (reloc_vector != NULL)

		    free (reloc_vector);

		  return FALSE;

		}

	      val = bfd_get_32 (abfd, info->stabs + r->address);

	      val &= r->howto->src_mask;

	      sym = *r->sym_ptr_ptr;

	      val += sym->value + sym->section->vma + r->addend;

	      bfd_put_32 (abfd, (bfd_vma) val, info->stabs + r->address);

	    }

	}

      if (reloc_vector != NULL)

	free (reloc_vector);

      /* First time through this function, build a table matching

	 function VM addresses to stabs, then sort based on starting

	 VM address.  Do this in two passes: once to count how many

	 table entries we'll need, and a second to actually build the

	 table.  */

      info->indextablesize = 0;

      nul_fun = NULL;

      for (stab = info->stabs; stab < info->stabs + stabsize; stab += STABSIZE)

	{

	  if (stab[TYPEOFF] == (bfd_byte) N_SO)

	    {

	      /* if we did not see a function def, leave space for one.  */

	      if (nul_fun != NULL)

		++info->indextablesize;

	      /* N_SO with null name indicates EOF */

	      if (bfd_get_32 (abfd, stab + STRDXOFF) == 0)

		nul_fun = NULL;

	      else

		{

		  nul_fun = stab;

	      /* two N_SO's in a row is a filename and directory. Skip */

		  if (stab + STABSIZE + TYPEOFF < info->stabs + stabsize

		  && *(stab + STABSIZE + TYPEOFF) == (bfd_byte) N_SO)

		  stab += STABSIZE;