276 lines
8.0 KiB
C
276 lines
8.0 KiB
C
/* Copyright (C) 2001-2020 Free Software Foundation, Inc.
|
||
|
||
This file is part of GCC.
|
||
|
||
GCC 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, or (at your option)
|
||
any later version.
|
||
|
||
GCC 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.
|
||
|
||
Under Section 7 of GPL version 3, you are granted additional
|
||
permissions described in the GCC Runtime Library Exception, version
|
||
3.1, as published by the Free Software Foundation.
|
||
|
||
You should have received a copy of the GNU General Public License and
|
||
a copy of the GCC Runtime Library Exception along with this program;
|
||
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
|
||
<http://www.gnu.org/licenses/>. */
|
||
|
||
/* Locate the FDE entry for a given address, using Darwin's keymgr support. */
|
||
|
||
#include "tconfig.h"
|
||
#include "tsystem.h"
|
||
#include <string.h>
|
||
#include <stdlib.h>
|
||
#include "dwarf2.h"
|
||
#include "unwind.h"
|
||
#define NO_BASE_OF_ENCODED_VALUE
|
||
#define DWARF2_OBJECT_END_PTR_EXTENSION
|
||
#include "unwind-pe.h"
|
||
#include "unwind-dw2-fde.h"
|
||
/* Carefully don't include gthr.h. */
|
||
|
||
typedef int __gthread_mutex_t;
|
||
#define __gthread_mutex_lock(x) (void)(x)
|
||
#define __gthread_mutex_unlock(x) (void)(x)
|
||
|
||
static const fde * _Unwind_Find_registered_FDE (void *pc,
|
||
struct dwarf_eh_bases *bases);
|
||
|
||
#define _Unwind_Find_FDE _Unwind_Find_registered_FDE
|
||
#include "unwind-dw2-fde.c"
|
||
#undef _Unwind_Find_FDE
|
||
|
||
/* KeyMgr stuff. */
|
||
#define KEYMGR_GCC3_LIVE_IMAGE_LIST 301 /* loaded images */
|
||
#define KEYMGR_GCC3_DW2_OBJ_LIST 302 /* Dwarf2 object list */
|
||
|
||
extern void *_keymgr_get_and_lock_processwide_ptr (int);
|
||
extern void _keymgr_set_and_unlock_processwide_ptr (int, void *);
|
||
extern void _keymgr_unlock_processwide_ptr (int);
|
||
|
||
struct mach_header;
|
||
struct mach_header_64;
|
||
extern char *getsectdatafromheader (struct mach_header*, const char*,
|
||
const char *, unsigned long *);
|
||
extern char *getsectdatafromheader_64 (struct mach_header_64*, const char*,
|
||
const char *, unsigned long *);
|
||
|
||
/* This is referenced from KEYMGR_GCC3_DW2_OBJ_LIST. */
|
||
struct km_object_info {
|
||
struct object *seen_objects;
|
||
struct object *unseen_objects;
|
||
unsigned spare[2];
|
||
};
|
||
|
||
/* Node of KEYMGR_GCC3_LIVE_IMAGE_LIST. Info about each resident image. */
|
||
struct live_images {
|
||
unsigned long this_size; /* sizeof (live_images) */
|
||
struct mach_header *mh; /* the image info */
|
||
unsigned long vm_slide;
|
||
void (*destructor)(struct live_images *); /* destructor for this */
|
||
struct live_images *next;
|
||
unsigned int examined_p;
|
||
void *fde;
|
||
void *object_info;
|
||
unsigned long info[2]; /* Future use. */
|
||
};
|
||
|
||
/* Bits in the examined_p field of struct live_images. */
|
||
enum {
|
||
EXAMINED_IMAGE_MASK = 1, /* We've seen this one. */
|
||
ALLOCED_IMAGE_MASK = 2, /* The FDE entries were allocated by
|
||
malloc, and must be freed. This isn't
|
||
used by newer libgcc versions. */
|
||
IMAGE_IS_TEXT_MASK = 4, /* This image is in the TEXT segment. */
|
||
DESTRUCTOR_MAY_BE_CALLED_LIVE = 8 /* The destructor may be called on an
|
||
object that's part of the live
|
||
image list. */
|
||
};
|
||
|
||
/* Delete any data we allocated on a live_images structure. Either
|
||
IMAGE has already been removed from the
|
||
KEYMGR_GCC3_LIVE_IMAGE_LIST and the struct will be deleted
|
||
after we return, or that list is locked and we're being called
|
||
because this object might be about to be unloaded. Called by
|
||
KeyMgr. */
|
||
|
||
static void
|
||
live_image_destructor (struct live_images *image)
|
||
{
|
||
if (image->object_info)
|
||
{
|
||
struct km_object_info *the_obj_info;
|
||
|
||
the_obj_info =
|
||
_keymgr_get_and_lock_processwide_ptr (KEYMGR_GCC3_DW2_OBJ_LIST);
|
||
if (the_obj_info)
|
||
{
|
||
seen_objects = the_obj_info->seen_objects;
|
||
unseen_objects = the_obj_info->unseen_objects;
|
||
|
||
/* Free any sorted arrays. */
|
||
__deregister_frame_info_bases (image->fde);
|
||
|
||
the_obj_info->seen_objects = seen_objects;
|
||
the_obj_info->unseen_objects = unseen_objects;
|
||
}
|
||
_keymgr_set_and_unlock_processwide_ptr (KEYMGR_GCC3_DW2_OBJ_LIST,
|
||
the_obj_info);
|
||
|
||
free (image->object_info);
|
||
image->object_info = NULL;
|
||
if (image->examined_p & ALLOCED_IMAGE_MASK)
|
||
free (image->fde);
|
||
image->fde = NULL;
|
||
}
|
||
image->examined_p = 0;
|
||
image->destructor = NULL;
|
||
}
|
||
|
||
/* Run through the list of live images. If we can allocate memory,
|
||
give each unseen image a new `struct object'. Even if we can't,
|
||
check whether the PC is inside the FDE of each unseen image.
|
||
*/
|
||
|
||
static inline const fde *
|
||
examine_objects (void *pc, struct dwarf_eh_bases *bases, int dont_alloc)
|
||
{
|
||
const fde *result = NULL;
|
||
struct live_images *image;
|
||
|
||
image = _keymgr_get_and_lock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST);
|
||
|
||
for (; image != NULL; image = image->next)
|
||
if ((image->examined_p & EXAMINED_IMAGE_MASK) == 0)
|
||
{
|
||
char *fde = NULL;
|
||
unsigned long sz;
|
||
|
||
/* For ppc only check whether or not we have __DATA eh frames. */
|
||
#ifdef __ppc__
|
||
fde = getsectdatafromheader (image->mh, "__DATA", "__eh_frame", &sz);
|
||
#endif
|
||
|
||
if (fde == NULL)
|
||
{
|
||
#if __LP64__
|
||
fde = getsectdatafromheader_64 ((struct mach_header_64 *) image->mh,
|
||
"__TEXT", "__eh_frame", &sz);
|
||
#else
|
||
fde = getsectdatafromheader (image->mh, "__TEXT",
|
||
"__eh_frame", &sz);
|
||
#endif
|
||
if (fde != NULL)
|
||
image->examined_p |= IMAGE_IS_TEXT_MASK;
|
||
}
|
||
|
||
/* If .eh_frame is empty, don't register at all. */
|
||
if (fde != NULL && sz > 0)
|
||
{
|
||
char *real_fde = (fde + image->vm_slide);
|
||
struct object *ob = NULL;
|
||
struct object panicob;
|
||
|
||
if (! dont_alloc)
|
||
ob = calloc (1, sizeof (struct object));
|
||
dont_alloc |= ob == NULL;
|
||
if (dont_alloc)
|
||
ob = &panicob;
|
||
|
||
ob->pc_begin = (void *)-1;
|
||
ob->tbase = 0;
|
||
ob->dbase = 0;
|
||
ob->u.single = (struct dwarf_fde *)real_fde;
|
||
ob->s.i = 0;
|
||
ob->s.b.encoding = DW_EH_PE_omit;
|
||
ob->fde_end = real_fde + sz;
|
||
|
||
image->fde = real_fde;
|
||
|
||
result = search_object (ob, pc);
|
||
|
||
if (! dont_alloc)
|
||
{
|
||
struct object **p;
|
||
|
||
image->destructor = live_image_destructor;
|
||
image->object_info = ob;
|
||
|
||
image->examined_p |= (EXAMINED_IMAGE_MASK
|
||
| DESTRUCTOR_MAY_BE_CALLED_LIVE);
|
||
|
||
/* Insert the object into the classified list. */
|
||
for (p = &seen_objects; *p ; p = &(*p)->next)
|
||
if ((*p)->pc_begin < ob->pc_begin)
|
||
break;
|
||
ob->next = *p;
|
||
*p = ob;
|
||
}
|
||
|
||
if (result)
|
||
{
|
||
int encoding;
|
||
_Unwind_Ptr func;
|
||
|
||
bases->tbase = ob->tbase;
|
||
bases->dbase = ob->dbase;
|
||
|
||
encoding = ob->s.b.encoding;
|
||
if (ob->s.b.mixed_encoding)
|
||
encoding = get_fde_encoding (result);
|
||
read_encoded_value_with_base (encoding,
|
||
base_from_object (encoding, ob),
|
||
result->pc_begin, &func);
|
||
bases->func = (void *) func;
|
||
break;
|
||
}
|
||
}
|
||
else
|
||
image->examined_p |= EXAMINED_IMAGE_MASK;
|
||
}
|
||
|
||
_keymgr_unlock_processwide_ptr (KEYMGR_GCC3_LIVE_IMAGE_LIST);
|
||
|
||
return result;
|
||
}
|
||
|
||
const fde *
|
||
_Unwind_Find_FDE (void *pc, struct dwarf_eh_bases *bases)
|
||
{
|
||
struct km_object_info *the_obj_info;
|
||
const fde *ret = NULL;
|
||
|
||
the_obj_info =
|
||
_keymgr_get_and_lock_processwide_ptr (KEYMGR_GCC3_DW2_OBJ_LIST);
|
||
if (! the_obj_info)
|
||
the_obj_info = calloc (1, sizeof (*the_obj_info));
|
||
|
||
if (the_obj_info != NULL)
|
||
{
|
||
seen_objects = the_obj_info->seen_objects;
|
||
unseen_objects = the_obj_info->unseen_objects;
|
||
|
||
ret = _Unwind_Find_registered_FDE (pc, bases);
|
||
}
|
||
|
||
/* OK, didn't find it in the list of FDEs we've seen before,
|
||
so go through and look at the new ones. */
|
||
if (ret == NULL)
|
||
ret = examine_objects (pc, bases, the_obj_info == NULL);
|
||
|
||
if (the_obj_info != NULL)
|
||
{
|
||
the_obj_info->seen_objects = seen_objects;
|
||
the_obj_info->unseen_objects = unseen_objects;
|
||
}
|
||
_keymgr_set_and_unlock_processwide_ptr (KEYMGR_GCC3_DW2_OBJ_LIST,
|
||
the_obj_info);
|
||
return ret;
|
||
}
|