[8/8] Remove __morecore and __default_morecore
Checks
Commit Message
Make the __morecore and __default_morecore symbols compat-only and
remove their declarations from the API.
---
NEWS | 5 +++++
include/stdlib.h | 3 ---
malloc/arena.c | 12 ++----------
malloc/hooks.c | 3 +++
malloc/malloc-internal.h | 5 +++++
malloc/malloc.c | 4 +---
malloc/malloc.h | 8 --------
malloc/morecore.c | 15 +++++++++++++--
8 files changed, 29 insertions(+), 26 deletions(-)
Comments
Siddhesh Poyarekar <siddhesh@sourceware.org> writes:
> Make the __morecore and __default_morecore symbols compat-only and
> remove their declarations from the API.
> diff --git a/NEWS b/NEWS
>
> +* The __morecore and __after_morecore_hook malloc hooks and the default
> + implementation __default_morecore have been removed from the API. Existing
> + applications will continue to link against these symbols but the interfaces
> + no longer have any effect on malloc.
> +
Ok.
> diff --git a/include/stdlib.h b/include/stdlib.h
> index e2453c1896..c5cccce85c 100644
> --- a/include/stdlib.h
> +++ b/include/stdlib.h
> @@ -300,9 +300,6 @@ libc_hidden_proto (__qfcvt_r)
> # define MB_CUR_MAX (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MB_CUR_MAX))
> # endif
>
> -extern void *__default_morecore (ptrdiff_t) __THROW;
> -libc_hidden_proto (__default_morecore)
> -
Ok.
> diff --git a/malloc/arena.c b/malloc/arena.c
> -#if defined(SHARED) || defined(USE_MTAG)
> -static void *
> -__failing_morecore (ptrdiff_t d)
> -{
> - return (void *) MORECORE_FAILURE;
> -}
> -#endif
> -
Ok.
> @@ -300,7 +292,7 @@ ptmalloc_init (void)
> and that morecore does not support tagged regions, then
> disable it. */
> if (__MTAG_SBRK_UNTAGGED)
> - __morecore = __failing_morecore;
> + __always_fail_morecore = true;
Ok.
> @@ -313,7 +305,7 @@ ptmalloc_init (void)
> generic sbrk implementation also enforces this, but it is not
> used on Hurd. */
> if (!__libc_initial)
> - __morecore = __failing_morecore;
> + __always_fail_morecore = true;
> #endif
Ok.
> diff --git a/malloc/hooks.c b/malloc/hooks.c
>
> +void *(*__morecore)(ptrdiff_t);
> +compat_symbol (libc, __morecore, __morecore, GLIBC_2_0);
Ok.
> diff --git a/malloc/malloc-internal.h b/malloc/malloc-internal.h
>
> #include <malloc-machine.h>
> #include <malloc-sysdep.h>
> +#include <stdbool.h>
Ok.
> @@ -63,6 +64,8 @@
>
> #define top(ar_ptr) ((ar_ptr)->top)
>
> +extern bool __always_fail_morecore attribute_hidden;
> +
Ok
> @@ -78,4 +81,6 @@ void __malloc_arena_thread_freeres (void) attribute_hidden;
> /* Activate a standard set of debugging hooks. */
> void __malloc_check_init (void) attribute_hidden;
>
> +extern void *__glibc_morecore (ptrdiff_t) attribute_hidden;
> +
Ok.
> diff --git a/malloc/malloc.c b/malloc/malloc.c
>
>
> /* Definition for getting more memory from the OS. */
> -#define MORECORE (*__morecore)
> +#define MORECORE (*__glibc_morecore)
> #define MORECORE_FAILURE 0
> -void * __default_morecore (ptrdiff_t);
> -void *(*__morecore)(ptrdiff_t) = __default_morecore;
Ok.
> diff --git a/malloc/malloc.h b/malloc/malloc.h
> @@ -76,14 +76,6 @@ extern void *valloc (size_t __size) __THROW __attribute_malloc__
> extern void *pvalloc (size_t __size) __THROW __attribute_malloc__
> __wur __attr_dealloc_free;
>
> -/* Underlying allocation function; successive calls should return
> - contiguous pieces of memory. */
> -extern void *(*__morecore) (ptrdiff_t __size) __MALLOC_DEPRECATED;
> -
> -/* Default value of `__morecore'. */
> -extern void *__default_morecore (ptrdiff_t __size)
> -__THROW __attribute_malloc__ __MALLOC_DEPRECATED;
> -
Ok.
> diff --git a/malloc/morecore.c b/malloc/morecore.c
> index 047228779b..c85a85c0eb 100644
> --- a/malloc/morecore.c
> +++ b/malloc/morecore.c
> @@ -38,16 +38,27 @@ libc_hidden_proto (__sbrk)
> # define NULL 0
> #endif
>
> +#if defined(SHARED) || defined(USE_MTAG)
> +bool __always_fail_morecore = false;
> +#endif
> +
Ok.
> /* Allocate INCREMENT more bytes of data space,
> and return the start of data space, or NULL on errors.
> If INCREMENT is negative, shrink data space. */
> void *
> -__default_morecore (ptrdiff_t increment)
> +__glibc_morecore (ptrdiff_t increment)
> {
> +#if defined(SHARED) || defined(USE_MTAG)
> + if (__always_fail_morecore)
> + return NULL;
> +#endif
> +
> void *result = (void *) __sbrk (increment);
> if (result == (void *) -1)
> return NULL;
>
> return result;
> }
> -libc_hidden_def (__default_morecore)
> +#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_34)
> +compat_symbol (libc, __glibc_morecore, __default_morecore, GLIBC_2_0);
> +#endif
Ok.
LGTM
Reviewed-by: DJ Delorie <dj@redhat.com>
@@ -77,6 +77,11 @@ Deprecated and removed features, and other changes affecting compatibility:
legacy programs until they are updated to remove references to the memory
allocation hooks.
+* The __morecore and __after_morecore_hook malloc hooks and the default
+ implementation __default_morecore have been removed from the API. Existing
+ applications will continue to link against these symbols but the interfaces
+ no longer have any effect on malloc.
+
Changes to build and runtime requirements:
* On Linux, the shm_open, sem_open, and related functions now expect the
@@ -300,9 +300,6 @@ libc_hidden_proto (__qfcvt_r)
# define MB_CUR_MAX (_NL_CURRENT_WORD (LC_CTYPE, _NL_CTYPE_MB_CUR_MAX))
# endif
-extern void *__default_morecore (ptrdiff_t) __THROW;
-libc_hidden_proto (__default_morecore)
-
struct abort_msg_s
{
unsigned int size;
@@ -272,14 +272,6 @@ next_env_entry (char ***position)
#endif
-#if defined(SHARED) || defined(USE_MTAG)
-static void *
-__failing_morecore (ptrdiff_t d)
-{
- return (void *) MORECORE_FAILURE;
-}
-#endif
-
#ifdef SHARED
extern struct dl_open_hook *_dl_open_hook;
libc_hidden_proto (_dl_open_hook);
@@ -300,7 +292,7 @@ ptmalloc_init (void)
and that morecore does not support tagged regions, then
disable it. */
if (__MTAG_SBRK_UNTAGGED)
- __morecore = __failing_morecore;
+ __always_fail_morecore = true;
mtag_enabled = true;
mtag_mmap_flags = __MTAG_MMAP_FLAGS;
@@ -313,7 +305,7 @@ ptmalloc_init (void)
generic sbrk implementation also enforces this, but it is not
used on Hurd. */
if (!__libc_initial)
- __morecore = __failing_morecore;
+ __always_fail_morecore = true;
#endif
thread_arena = &main_arena;
@@ -81,6 +81,9 @@ compat_symbol (libc, __memalign_hook, __memalign_hook, GLIBC_2_0);
void weak_variable (*__after_morecore_hook) (void) = NULL;
compat_symbol (libc, __after_morecore_hook, __after_morecore_hook, GLIBC_2_0);
+void *(*__morecore)(ptrdiff_t);
+compat_symbol (libc, __morecore, __morecore, GLIBC_2_0);
+
/* These hooks will get executed only through the interposed allocator
functions in libmalloc_compathooks. This means that the calls to malloc,
realloc, etc. will lead back into the interposed functions, which is what we
@@ -21,6 +21,7 @@
#include <malloc-machine.h>
#include <malloc-sysdep.h>
+#include <stdbool.h>
/* INTERNAL_SIZE_T is the word-size used for internal bookkeeping of
chunk sizes.
@@ -63,6 +64,8 @@
#define top(ar_ptr) ((ar_ptr)->top)
+extern bool __always_fail_morecore attribute_hidden;
+
/* Called in the parent process before a fork. */
void __malloc_fork_lock_parent (void) attribute_hidden;
@@ -78,4 +81,6 @@ void __malloc_arena_thread_freeres (void) attribute_hidden;
/* Activate a standard set of debugging hooks. */
void __malloc_check_init (void) attribute_hidden;
+extern void *__glibc_morecore (ptrdiff_t) attribute_hidden;
+
#endif /* _MALLOC_INTERNAL_H */
@@ -382,10 +382,8 @@ __malloc_assert (const char *assertion, const char *file, unsigned int line,
/* Definition for getting more memory from the OS. */
-#define MORECORE (*__morecore)
+#define MORECORE (*__glibc_morecore)
#define MORECORE_FAILURE 0
-void * __default_morecore (ptrdiff_t);
-void *(*__morecore)(ptrdiff_t) = __default_morecore;
/* Memory tagging. */
@@ -76,14 +76,6 @@ extern void *valloc (size_t __size) __THROW __attribute_malloc__
extern void *pvalloc (size_t __size) __THROW __attribute_malloc__
__wur __attr_dealloc_free;
-/* Underlying allocation function; successive calls should return
- contiguous pieces of memory. */
-extern void *(*__morecore) (ptrdiff_t __size) __MALLOC_DEPRECATED;
-
-/* Default value of `__morecore'. */
-extern void *__default_morecore (ptrdiff_t __size)
-__THROW __attribute_malloc__ __MALLOC_DEPRECATED;
-
/* SVID2/XPG mallinfo structure */
struct mallinfo
@@ -38,16 +38,27 @@ libc_hidden_proto (__sbrk)
# define NULL 0
#endif
+#if defined(SHARED) || defined(USE_MTAG)
+bool __always_fail_morecore = false;
+#endif
+
/* Allocate INCREMENT more bytes of data space,
and return the start of data space, or NULL on errors.
If INCREMENT is negative, shrink data space. */
void *
-__default_morecore (ptrdiff_t increment)
+__glibc_morecore (ptrdiff_t increment)
{
+#if defined(SHARED) || defined(USE_MTAG)
+ if (__always_fail_morecore)
+ return NULL;
+#endif
+
void *result = (void *) __sbrk (increment);
if (result == (void *) -1)
return NULL;
return result;
}
-libc_hidden_def (__default_morecore)
+#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_34)
+compat_symbol (libc, __glibc_morecore, __default_morecore, GLIBC_2_0);
+#endif