From 968dad0ab1f367a087ff4ad503b511dd0c565adc Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Wed, 19 Jan 2011 15:32:35 -0500 Subject: Fix ordering of DSO constructors and destructors. --- elf/dl-fini.c | 151 +++++++++++++++++++++++++++++----------------------------- 1 file changed, 75 insertions(+), 76 deletions(-) (limited to 'elf/dl-fini.c') diff --git a/elf/dl-fini.c b/elf/dl-fini.c index ff4c33e..ba6c62a 100644 --- a/elf/dl-fini.c +++ b/elf/dl-fini.c @@ -1,5 +1,6 @@ /* Call the termination functions of loaded shared objects. - Copyright (C) 1995,96,1998-2002,2004-2005,2009 Free Software Foundation, Inc. + Copyright (C) 1995,96,1998-2002,2004-2005,2009,2011 + 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 @@ -32,86 +33,84 @@ internal_function _dl_sort_fini (struct link_map *l, struct link_map **maps, size_t nmaps, char *used, Lmid_t ns) { - if (ns == LM_ID_BASE) - /* The main executable always comes first. */ - l = l->l_next; - - for (; l != NULL; l = l->l_next) - /* Do not handle ld.so in secondary namespaces and object which - are not removed. */ - if (l == l->l_real && l->l_idx != -1) - { - /* Find the place in the 'maps' array. */ - unsigned int j; - for (j = ns == LM_ID_BASE ? 1 : 0; maps[j] != l; ++j) - assert (j < nmaps); - - /* Find all object for which the current one is a dependency - and move the found object (if necessary) in front. */ - for (unsigned int k = j + 1; k < nmaps; ++k) - { - struct link_map **runp = maps[k]->l_initfini; - if (runp != NULL) - { - while (*runp != NULL) - if (*runp == l) + /* We can skip looking for the binary itself which is at the front + of the search list for the main namespace. */ + assert (nmaps > 1); + unsigned int i = ns == LM_ID_BASE; + bool seen[nmaps]; + memset (seen, false, nmaps * sizeof (seen[0])); + while (1) + { + /* Keep track of which object we looked at this round. */ + seen[i] = true; + struct link_map *thisp = maps[i]; + + /* Do not handle ld.so in secondary namespaces and object 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 (__builtin_expect (*runp++ == thisp, 0)) + { + 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) { - struct link_map *here = maps[k]; + char here_used = used[i]; + memmove (&used[i], &used[i + 1], + (k - i) * sizeof (used[0])); + used[k] = here_used; + } - /* Move it now. */ - memmove (&maps[j] + 1, - &maps[j], (k - j) * sizeof (struct link_map *)); - maps[j] = here; + if (seen[i + 1]) + { + ++i; + goto next_clear; + } - if (used != NULL) - { - char here_used = used[k]; + memmove (&seen[i], &seen[i + 1], (k - i) * sizeof (seen[0])); + seen[k] = true; - memmove (&used[j] + 1, - &used[j], (k - j) * sizeof (char)); - used[j] = here_used; - } + goto next; + } - ++j; + if (__builtin_expect (maps[k]->l_reldeps != NULL, 0)) + { + unsigned int m = maps[k]->l_reldeps->act; + struct link_map **relmaps = &maps[k]->l_reldeps->list[0]; - break; - } - else - ++runp; - } - - if (__builtin_expect (maps[k]->l_reldeps != NULL, 0)) - { - unsigned int m = maps[k]->l_reldeps->act; - struct link_map **relmaps = &maps[k]->l_reldeps->list[0]; - - while (m-- > 0) - { - if (relmaps[m] == l) - { - struct link_map *here = maps[k]; - - /* Move it now. */ - memmove (&maps[j] + 1, - &maps[j], - (k - j) * sizeof (struct link_map *)); - maps[j] = here; - - if (used != NULL) - { - char here_used = used[k]; - - memmove (&used[j] + 1, - &used[j], (k - j) * sizeof (char)); - used[j] = here_used; - } - - break; - } - } - } - } - } + /* Look through the relocation dependencies of the object. */ + while (m-- > 0) + if (__builtin_expect (relmaps[m] == thisp, 0)) + goto move; + } + + --k; + } + + skip: + if (++i == nmaps) + break; + next_clear: + memset (&seen[i], false, (nmaps - i) * sizeof (seen[0])); + + next:; + } } @@ -196,7 +195,7 @@ _dl_fini (void) assert (ns == LM_ID_BASE || i == nloaded || i == nloaded - 1); nmaps = i; - if (nmaps != 0) + if (nmaps > 1) /* Now we have to do the sorting. */ _dl_sort_fini (GL(dl_ns)[ns]._ns_loaded, maps, nmaps, NULL, ns); -- cgit v1.1