0,0 → 1,1426 |
/* Generic symbol-table support for the BFD library. |
Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, |
2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2012 |
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 <<asymbol>> 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 <<asymbol>>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 <<bfd_make_empty_symbol>>. 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 <<a.out>> 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 <<bfd_read_minisymbols>> function will read the symbols |
into memory in an internal form. It will return a <<void *>> |
pointer to a block of memory, a symbol count, and the size of |
each symbol. The pointer is allocated using <<malloc>>, and |
should be freed by the caller when it is no longer needed. |
|
The function <<bfd_minisymbol_to_symbol>> will take a pointer |
to a minisymbol, and a pointer to a structure returned by |
<<bfd_make_empty_symbol>>, and return a <<asymbol>> structure. |
The return value may or may not be the same as the value from |
<<bfd_make_empty_symbol>> which was passed in. |
|
*/ |
|
/* |
DOCDD |
INODE |
typedef asymbol, symbol handling functions, Mini Symbols, Symbols |
|
*/ |
/* |
SUBSECTION |
typedef asymbol |
|
An <<asymbol>> 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; <<static>> in <<C>>. The value |
. is the offset into the section of the data. *} |
.#define BSF_LOCAL (1 << 0) |
. |
. {* The symbol has global scope; initialized data in <<C>>. 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: |
. <<BSF_LOCAL>>, <<BSF_COMMON>>, <<BSF_UNDEFINED>> or |
. <<BSF_GLOBAL>>. *} |
. |
. {* 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 <<ISFCN>> symbol |
. which is also <<C_EXT>> 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 <<asymbols>> 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 <<asymbol>> 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 <<asymbol>>. Building your own |
<<asymbol>> 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 <<asymbol>> 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 <<asymbol>> 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 <<TRUE>> on success, <<FALSE>> on error. Possible error |
returns are: |
|
o <<bfd_error_no_memory>> - |
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 *last_stab, *last_str; |
bfd_size_type stroff; |
struct indexentry *indexentry; |
char *file_name; |
char *directory_name; |
int saw_fun; |
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 *name; |
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); |
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; |
saw_fun = 1; |
for (stab = info->stabs; stab < info->stabs + stabsize; stab += STABSIZE) |
{ |
if (stab[TYPEOFF] == (bfd_byte) N_SO) |
{ |
/* N_SO with null name indicates EOF */ |
if (bfd_get_32 (abfd, stab + STRDXOFF) == 0) |
continue; |
|
/* if we did not see a function def, leave space for one. */ |
if (saw_fun == 0) |
++info->indextablesize; |
|
saw_fun = 0; |
|
/* two N_SO's in a row is a filename and directory. Skip */ |
if (stab + STABSIZE < info->stabs + stabsize |
&& *(stab + STABSIZE + TYPEOFF) == (bfd_byte) N_SO) |
{ |
stab += STABSIZE; |
} |
} |
else if (stab[TYPEOFF] == (bfd_byte) N_FUN) |
{ |
saw_fun = 1; |
++info->indextablesize; |
} |
} |
|
if (saw_fun == 0) |
++info->indextablesize; |
|
if (info->indextablesize == 0) |
return TRUE; |
++info->indextablesize; |
|
amt = info->indextablesize; |
amt *= sizeof (struct indexentry); |
info->indextable = (struct indexentry *) bfd_alloc (abfd, amt); |
if (info->indextable == NULL) |
return FALSE; |
|
file_name = NULL; |
directory_name = NULL; |
saw_fun = 1; |
stroff = 0; |
|
for (i = 0, last_stab = stab = info->stabs, last_str = str = info->strs; |
i < info->indextablesize && stab < info->stabs + stabsize; |
stab += STABSIZE) |
{ |
switch (stab[TYPEOFF]) |
{ |
case 0: |
/* This is the first entry in a compilation unit. */ |
if ((bfd_size_type) ((info->strs + strsize) - str) < stroff) |
break; |
str += stroff; |
stroff = bfd_get_32 (abfd, stab + VALOFF); |
break; |
|
case N_SO: |
/* The main file name. */ |
|
/* The following code creates a new indextable entry with |
a NULL function name if there were no N_FUNs in a file. |
Note that a N_SO without a file name is an EOF and |
there could be 2 N_SO following it with the new filename |
and directory. */ |
if (saw_fun == 0) |
{ |
info->indextable[i].val = bfd_get_32 (abfd, last_stab + VALOFF); |
info->indextable[i].stab = last_stab; |
info->indextable[i].str = last_str; |
info->indextable[i].directory_name = directory_name; |
info->indextable[i].file_name = file_name; |
info->indextable[i].function_name = NULL; |
++i; |
} |
saw_fun = 0; |
|
file_name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF); |
if (*file_name == '\0') |
{ |
directory_name = NULL; |
file_name = NULL; |
saw_fun = 1; |
} |
else |
{ |
last_stab = stab; |
last_str = str; |
if (stab + STABSIZE >= info->stabs + stabsize |
|| *(stab + STABSIZE + TYPEOFF) != (bfd_byte) N_SO) |
{ |
directory_name = NULL; |
} |
else |
{ |
/* Two consecutive N_SOs are a directory and a |
file name. */ |
stab += STABSIZE; |
directory_name = file_name; |
file_name = ((char *) str |
+ bfd_get_32 (abfd, stab + STRDXOFF)); |
} |
} |
break; |
|
case N_SOL: |
/* The name of an include file. */ |
file_name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF); |
break; |
|
case N_FUN: |
/* A function name. */ |
saw_fun = 1; |
name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF); |
|
if (*name == '\0') |
name = NULL; |
|
function_name = name; |
|
if (name == NULL) |
continue; |
|
info->indextable[i].val = bfd_get_32 (abfd, stab + VALOFF); |
info->indextable[i].stab = stab; |
info->indextable[i].str = str; |
info->indextable[i].directory_name = directory_name; |
info->indextable[i].file_name = file_name; |
info->indextable[i].function_name = function_name; |
++i; |
break; |
} |
} |
|
if (saw_fun == 0) |
{ |
info->indextable[i].val = bfd_get_32 (abfd, last_stab + VALOFF); |
info->indextable[i].stab = last_stab; |
info->indextable[i].str = last_str; |
info->indextable[i].directory_name = directory_name; |
info->indextable[i].file_name = file_name; |
info->indextable[i].function_name = NULL; |
++i; |
} |
|
info->indextable[i].val = (bfd_vma) -1; |
info->indextable[i].stab = info->stabs + stabsize; |
info->indextable[i].str = str; |
info->indextable[i].directory_name = NULL; |
info->indextable[i].file_name = NULL; |
info->indextable[i].function_name = NULL; |
++i; |
|
info->indextablesize = i; |
qsort (info->indextable, (size_t) i, sizeof (struct indexentry), |
cmpindexentry); |
|
*pinfo = info; |
} |
|
/* We are passed a section relative offset. The offsets in the |
stabs information are absolute. */ |
offset += bfd_get_section_vma (abfd, section); |
|
#ifdef ENABLE_CACHING |
if (info->cached_indexentry != NULL |
&& offset >= info->cached_offset |
&& offset < (info->cached_indexentry + 1)->val) |
{ |
stab = info->cached_stab; |
indexentry = info->cached_indexentry; |
file_name = info->cached_file_name; |
} |
else |
#endif |
{ |
long low, high; |
long mid = -1; |
|
/* Cache non-existent or invalid. Do binary search on |
indextable. */ |
indexentry = NULL; |
|
low = 0; |
high = info->indextablesize - 1; |
while (low != high) |
{ |
mid = (high + low) / 2; |
if (offset >= info->indextable[mid].val |
&& offset < info->indextable[mid + 1].val) |
{ |
indexentry = &info->indextable[mid]; |
break; |
} |
|
if (info->indextable[mid].val > offset) |
high = mid; |
else |
low = mid + 1; |
} |
|
if (indexentry == NULL) |
return TRUE; |
|
stab = indexentry->stab + STABSIZE; |
file_name = indexentry->file_name; |
} |
|
directory_name = indexentry->directory_name; |
str = indexentry->str; |
|
saw_line = FALSE; |
saw_func = FALSE; |
for (; stab < (indexentry+1)->stab; stab += STABSIZE) |
{ |
bfd_boolean done; |
bfd_vma val; |
|
done = FALSE; |
|
switch (stab[TYPEOFF]) |
{ |
case N_SOL: |
/* The name of an include file. */ |
val = bfd_get_32 (abfd, stab + VALOFF); |
if (val <= offset) |
{ |
file_name = (char *) str + bfd_get_32 (abfd, stab + STRDXOFF); |
*pline = 0; |
} |
break; |
|
case N_SLINE: |
case N_DSLINE: |
case N_BSLINE: |
/* A line number. If the function was specified, then the value |
is relative to the start of the function. Otherwise, the |
value is an absolute address. */ |
val = ((indexentry->function_name ? indexentry->val : 0) |
+ bfd_get_32 (abfd, stab + VALOFF)); |
/* If this line starts before our desired offset, or if it's |
the first line we've been able to find, use it. The |
!saw_line check works around a bug in GCC 2.95.3, which emits |
the first N_SLINE late. */ |
if (!saw_line || val <= offset) |
{ |
*pline = bfd_get_16 (abfd, stab + DESCOFF); |
|
#ifdef ENABLE_CACHING |
info->cached_stab = stab; |
info->cached_offset = val; |
info->cached_file_name = file_name; |
info->cached_indexentry = indexentry; |
#endif |
} |
if (val > offset) |
done = TRUE; |
saw_line = TRUE; |
break; |
|
case N_FUN: |
case N_SO: |
if (saw_func || saw_line) |
done = TRUE; |
saw_func = TRUE; |
break; |
} |
|
if (done) |
break; |
} |
|
*pfound = TRUE; |
|
if (file_name == NULL || IS_ABSOLUTE_PATH (file_name) |
|| directory_name == NULL) |
*pfilename = file_name; |
else |
{ |
size_t dirlen; |
|
dirlen = strlen (directory_name); |
if (info->filename == NULL |
|| filename_ncmp (info->filename, directory_name, dirlen) != 0 |
|| filename_cmp (info->filename + dirlen, file_name) != 0) |
{ |
size_t len; |
|
/* Don't free info->filename here. objdump and other |
apps keep a copy of a previously returned file name |
pointer. */ |
len = strlen (file_name) + 1; |
info->filename = (char *) bfd_alloc (abfd, dirlen + len); |
if (info->filename == NULL) |
return FALSE; |
memcpy (info->filename, directory_name, dirlen); |
memcpy (info->filename + dirlen, file_name, len); |
} |
|
*pfilename = info->filename; |
} |
|
if (indexentry->function_name != NULL) |
{ |
char *s; |
|
/* This will typically be something like main:F(0,1), so we want |
to clobber the colon. It's OK to change the name, since the |
string is in our own local storage anyhow. */ |
s = strchr (indexentry->function_name, ':'); |
if (s != NULL) |
*s = '\0'; |
|
*pfnname = indexentry->function_name; |
} |
|
return TRUE; |
} |