c2c299fd24
Combine the four places where link maps are sorted into a single function. This also moves the logic to skip the first map (representing the main binary) to the callers.
123 lines
3.4 KiB
C
123 lines
3.4 KiB
C
/* Sort array of link maps according to dependencies.
|
|
Copyright (C) 2017 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
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/>. */
|
|
|
|
#include <ldsodefs.h>
|
|
|
|
|
|
/* Sort array MAPS according to dependencies of the contained objects.
|
|
Array USED, if non-NULL, is permutated along MAPS. If FOR_FINI this is
|
|
called for finishing an object. */
|
|
void
|
|
_dl_sort_maps (struct link_map **maps, unsigned int nmaps, char *used,
|
|
bool for_fini)
|
|
{
|
|
/* A list of one element need not be sorted. */
|
|
if (nmaps <= 1)
|
|
return;
|
|
|
|
unsigned int i = 0;
|
|
uint16_t seen[nmaps];
|
|
memset (seen, 0, nmaps * sizeof (seen[0]));
|
|
while (1)
|
|
{
|
|
/* Keep track of which object we looked at this round. */
|
|
++seen[i];
|
|
struct link_map *thisp = maps[i];
|
|
|
|
if (__glibc_unlikely (for_fini))
|
|
{
|
|
/* Do not handle ld.so in secondary namespaces and objects which
|
|
are not removed. */
|
|
if (thisp != thisp->l_real || thisp->l_idx == -1)
|
|
goto skip;
|
|
}
|
|
|
|
/* Find the last object in the list for which the current one is
|
|
a dependency and move the current object behind the object
|
|
with the dependency. */
|
|
unsigned int k = nmaps - 1;
|
|
while (k > i)
|
|
{
|
|
struct link_map **runp = maps[k]->l_initfini;
|
|
if (runp != NULL)
|
|
/* Look through the dependencies of the object. */
|
|
while (*runp != NULL)
|
|
if (__glibc_unlikely (*runp++ == thisp))
|
|
{
|
|
move:
|
|
/* Move the current object to the back past the last
|
|
object with it as the dependency. */
|
|
memmove (&maps[i], &maps[i + 1],
|
|
(k - i) * sizeof (maps[0]));
|
|
maps[k] = thisp;
|
|
|
|
if (used != NULL)
|
|
{
|
|
char here_used = used[i];
|
|
memmove (&used[i], &used[i + 1],
|
|
(k - i) * sizeof (used[0]));
|
|
used[k] = here_used;
|
|
}
|
|
|
|
if (seen[i + 1] > nmaps - i)
|
|
{
|
|
++i;
|
|
goto next_clear;
|
|
}
|
|
|
|
uint16_t this_seen = seen[i];
|
|
memmove (&seen[i], &seen[i + 1], (k - i) * sizeof (seen[0]));
|
|
seen[k] = this_seen;
|
|
|
|
goto next;
|
|
}
|
|
|
|
if (__glibc_unlikely (for_fini && maps[k]->l_reldeps != NULL))
|
|
{
|
|
unsigned int m = maps[k]->l_reldeps->act;
|
|
struct link_map **relmaps = &maps[k]->l_reldeps->list[0];
|
|
|
|
/* Look through the relocation dependencies of the object. */
|
|
while (m-- > 0)
|
|
if (__glibc_unlikely (relmaps[m] == thisp))
|
|
{
|
|
/* If a cycle exists with a link time dependency,
|
|
preserve the latter. */
|
|
struct link_map **runp = thisp->l_initfini;
|
|
if (runp != NULL)
|
|
while (*runp != NULL)
|
|
if (__glibc_unlikely (*runp++ == maps[k]))
|
|
goto ignore;
|
|
goto move;
|
|
}
|
|
ignore:;
|
|
}
|
|
|
|
--k;
|
|
}
|
|
|
|
skip:
|
|
if (++i == nmaps)
|
|
break;
|
|
next_clear:
|
|
memset (&seen[i], 0, (nmaps - i) * sizeof (seen[0]));
|
|
|
|
next:;
|
|
}
|
|
}
|