aboutsummaryrefslogtreecommitdiff
path: root/malloc
diff options
context:
space:
mode:
authorFlorian Weimer <fweimer@redhat.com>2016-06-10 10:46:05 +0200
committerFlorian Weimer <fweimer@redhat.com>2016-06-10 10:46:05 +0200
commit2ba3cfa1607c36613f3b30fb1ae4ec530245ce64 (patch)
tree4c215fe75ef1c016943e36821137257480097e01 /malloc
parentf00faa4a43706d85ad8d4d2c970d3f52f0f63bfb (diff)
downloadglibc-2ba3cfa1607c36613f3b30fb1ae4ec530245ce64.tar
glibc-2ba3cfa1607c36613f3b30fb1ae4ec530245ce64.tar.gz
glibc-2ba3cfa1607c36613f3b30fb1ae4ec530245ce64.tar.bz2
glibc-2ba3cfa1607c36613f3b30fb1ae4ec530245ce64.zip
malloc: Remove __malloc_initialize_hook from the API [BZ #19564]
__malloc_initialize_hook is interposed by application code, so the usual approach to define a compatibility symbol does not work. This commit adds a new mechanism based on #pragma GCC poison in <stdc-predef.h>.
Diffstat (limited to 'malloc')
-rw-r--r--malloc/Makefile14
-rw-r--r--malloc/arena.c4
-rw-r--r--malloc/malloc-hooks.h27
-rw-r--r--malloc/malloc.c16
-rw-r--r--malloc/malloc.h5
-rw-r--r--malloc/mcheck-init.c2
6 files changed, 60 insertions, 8 deletions
diff --git a/malloc/Makefile b/malloc/Makefile
index fa1730ecb7..91eb17dd7a 100644
--- a/malloc/Makefile
+++ b/malloc/Makefile
@@ -115,6 +115,20 @@ endif
include ../Rules
+# Support references to removed APIs. We use #pragma GCC poison in
+# <stdc-predef.h> to make it difficult to reference them. For select
+# source files, we work around this poisoning by defining a macro on
+# the command line (which is processed before <stdc-predef.h> and can
+# therefore use tokens poisoned later).
+poisoned_apis = \
+ __malloc_initialize_hook \
+
+unpoisoned_api_defines := \
+ $(foreach sym,$(poisoned_apis), \
+ $(patsubst %,-Dold%, $(sym))=$(sym))
+CPPFLAGS-malloc.c = $(unpoisoned_api_defines)
+CPPFLAGS-mcheck-init.c = $(unpoisoned_api_defines)
+
CFLAGS-mcheck-init.c = $(PIC-ccflag)
CFLAGS-obstack.c = $(uses-callbacks)
diff --git a/malloc/arena.c b/malloc/arena.c
index 1dd9deef0e..64a118c319 100644
--- a/malloc/arena.c
+++ b/malloc/arena.c
@@ -340,9 +340,11 @@ ptmalloc_init (void)
if (check_action != 0)
__malloc_check_init ();
}
- void (*hook) (void) = atomic_forced_read (__malloc_initialize_hook);
+#if HAVE_MALLOC_INIT_HOOK
+ void (*hook) (void) = atomic_forced_read (old__malloc_initialize_hook);
if (hook != NULL)
(*hook)();
+#endif
__malloc_initialized = 1;
}
diff --git a/malloc/malloc-hooks.h b/malloc/malloc-hooks.h
new file mode 100644
index 0000000000..3be391b6fb
--- /dev/null
+++ b/malloc/malloc-hooks.h
@@ -0,0 +1,27 @@
+/* Internal declarations of malloc hooks no longer in the public API.
+ Copyright (C) 2016 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; see the file COPYING.LIB. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef _MALLOC_HOOKS_H
+#define _MALLOC_HOOKS_H
+
+/* These hooks are no longer part of the public API and are poisoned
+ in <stdc-predef.h>. Their names here reflect the command-line
+ mapping which is used inside glibc to get past the poisoning. */
+void (*old__malloc_initialize_hook) (void);
+
+#endif /* _MALLOC_HOOKS_H */
diff --git a/malloc/malloc.c b/malloc/malloc.c
index 6f77d372a8..ac0f751593 100644
--- a/malloc/malloc.c
+++ b/malloc/malloc.c
@@ -491,6 +491,15 @@ void *(*__morecore)(ptrdiff_t) = __default_morecore;
#define HAVE_MREMAP 0
#endif
+/* We may need to support __malloc_initialize_hook for backwards
+ compatibility. */
+
+#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_24)
+# define HAVE_MALLOC_INIT_HOOK 1
+#else
+# define HAVE_MALLOC_INIT_HOOK 0
+#endif
+
/*
This version of malloc supports the standard SVID/XPG mallinfo
@@ -1841,7 +1850,12 @@ static void *realloc_hook_ini (void *ptr, size_t sz,
static void *memalign_hook_ini (size_t alignment, size_t sz,
const void *caller) __THROW;
-void weak_variable (*__malloc_initialize_hook) (void) = NULL;
+#if HAVE_MALLOC_INIT_HOOK
+void weak_variable (*old__malloc_initialize_hook) (void) = NULL;
+compat_symbol (libc, old__malloc_initialize_hook,
+ old__malloc_initialize_hook, GLIBC_2_0);
+#endif
+
void weak_variable (*__free_hook) (void *__ptr,
const void *) = NULL;
void *weak_variable (*__malloc_hook)
diff --git a/malloc/malloc.h b/malloc/malloc.h
index d95a3157a3..54b1862035 100644
--- a/malloc/malloc.h
+++ b/malloc/malloc.h
@@ -141,11 +141,6 @@ extern void *malloc_get_state (void) __THROW;
malloc_get_state(). */
extern int malloc_set_state (void *__ptr) __THROW;
-/* Called once when malloc is initialized; redefining this variable in
- the application provides the preferred way to set up the hook
- pointers. */
-extern void (*__MALLOC_HOOK_VOLATILE __malloc_initialize_hook) (void)
-__MALLOC_DEPRECATED;
/* Hooks for debugging and user-defined versions. */
extern void (*__MALLOC_HOOK_VOLATILE __free_hook) (void *__ptr,
const void *)
diff --git a/malloc/mcheck-init.c b/malloc/mcheck-init.c
index 8d63dd3488..3218bb03b9 100644
--- a/malloc/mcheck-init.c
+++ b/malloc/mcheck-init.c
@@ -27,4 +27,4 @@ turn_on_mcheck (void)
mcheck (NULL);
}
-void (*__malloc_initialize_hook) (void) = turn_on_mcheck;
+void (*old__malloc_initialize_hook) (void) = turn_on_mcheck;