glibc/sysdeps/tile/dl-runtime.c

160 lines
4.6 KiB
C

/* Copyright (C) 2011-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
/* Like x86_64, we pass the index of the relocation and not its offset.
In _dl_profile_fixup and _dl_call_pltexit we also use the index.
Therefore it is wasteful to compute the offset in the trampoline
just to reverse the operation immediately afterwards. */
#define reloc_offset reloc_arg * sizeof (PLTREL)
#define reloc_index reloc_arg
#include <elf/dl-runtime.c>
#include <sys/mman.h>
#include <arch/sim.h>
#include <dl-unmap-segments.h>
/* Like realpath(), but simplified: no dynamic memory use, no lstat(),
no set_errno(), no valid "rpath" on error, etc. This handles some
simple cases where the simulator might not have a valid entry for
a loaded Elf object, in particular dlopen() with a relative path.
For this relatively rare case, one could also imagine using
link_map.l_origin to avoid the getcwd() here, but the simpler code
here seems like a better solution. */
static char *
dl_realpath (const char *name, char *rpath)
{
char *dest;
const char *start, *end;
if (name[0] != '/')
{
if (!__getcwd (rpath, PATH_MAX))
return NULL;
dest = __rawmemchr (rpath, '\0');
}
else
{
rpath[0] = '/';
dest = rpath + 1;
}
for (start = end = name; *start; start = end)
{
/* Skip sequence of multiple path-separators. */
while (*start == '/')
++start;
/* Find end of path component. */
for (end = start; *end && *end != '/'; ++end)
/* Nothing. */;
if (end - start == 0)
break;
else if (end - start == 1 && start[0] == '.')
/* nothing */;
else if (end - start == 2 && start[0] == '.' && start[1] == '.')
{
/* Back up to previous component, ignore if at root already. */
if (dest > rpath + 1)
while ((--dest)[-1] != '/');
}
else
{
if (dest[-1] != '/')
*dest++ = '/';
if (dest + (end - start) >= rpath + PATH_MAX)
return NULL;
dest = __mempcpy (dest, start, end - start);
*dest = '\0';
}
}
if (dest > rpath + 1 && dest[-1] == '/')
--dest;
*dest = '\0';
return rpath;
}
/* Support notifying the simulator about new objects. */
void internal_function
_dl_after_load (struct link_map *l)
{
int shift;
char pathbuf[PATH_MAX];
char *path;
/* Don't bother if not in the simulator. */
if (__insn_mfspr (SPR_SIM_CONTROL) == 0)
return;
#define DLPUTC(c) __insn_mtspr (SPR_SIM_CONTROL, \
(SIM_CONTROL_DLOPEN \
| ((c) << _SIM_CONTROL_OPERATOR_BITS)))
/* Write the library address in hex. */
DLPUTC ('0');
DLPUTC ('x');
for (shift = (int) sizeof (unsigned long) * 8 - 4; shift >= 0; shift -= 4)
DLPUTC ("0123456789abcdef"[(l->l_map_start >> shift) & 0xF]);
DLPUTC (':');
/* Write the library path, including the terminating '\0'. */
path = dl_realpath (l->l_name, pathbuf) ?: l->l_name;
for (size_t i = 0;; i++)
{
DLPUTC (path[i]);
if (path[i] == '\0')
break;
}
#undef DLPUTC
}
/* Support notifying the simulator about removed objects prior to munmap(). */
static void
sim_dlclose (ElfW(Addr) map_start)
{
int shift;
/* Don't bother if not in the simulator. */
if (__insn_mfspr (SPR_SIM_CONTROL) == 0)
return;
#define DLPUTC(c) __insn_mtspr (SPR_SIM_CONTROL, \
(SIM_CONTROL_DLCLOSE \
| ((c) << _SIM_CONTROL_OPERATOR_BITS)))
/* Write the library address in hex. */
DLPUTC ('0');
DLPUTC ('x');
for (shift = (int) sizeof (unsigned long) * 8 - 4; shift >= 0; shift -= 4)
DLPUTC ("0123456789abcdef"[(map_start >> shift) & 0xF]);
DLPUTC ('\0');
#undef DLPUTC
}
void internal_function
_dl_unmap (struct link_map *map)
{
sim_dlclose (map->l_map_start);
_dl_unmap_segments (map);
}