Rather than define per-object rules in the Makefile, have small files
that define & include the right content. This simplifies the build
rules, and makes understanding the source a little easier (imo) as it
makes all the subdirs behave the same: you have 1 source file and it
produces 1 object. It's also about the same amount of boiler plate,
without having to define custom build rules that can fall out of sync.
This will also be important as we merge the libc.a build into the top
dir since it relies on a single flat list of objects for overrides.
Also take the opportunity to clean up the unnecessary header deps in
here. Automake provides dependency generation for free now.
This file is a little confusing: it provides all of the mallocr logic,
but is compiled multiple times to produce a unique symbol each time.
For example, building mallocr.c with -DDEFINE_FREER produces freer.o
that only defines _free_r(). This is fine for most symbols, but it's
a little confusing when defining mallocr itself -- we produce a file
with the same symbol name, but we still need -DDEFINE_MALLOCR. In
order to move the logic from the build rules to source files, using
mallocr.c both as a multiplexer and for defining a single symbol is a
bit tricky. It's possible (if we add a lot of redundant preprocessor
checks to mallocr.c, or we add complicated build flags just for this
one files), but it's easier if we simply rename this to a dedicated
file. So let's do that.
We do this as a dedicated commit because the next one will create a
new mallocr.c file and git's automatic diff algorithms can handle
trivial renames, but it can't handle renames+creates in the same
commit.
Simplify the build system logic a bit by moving the mallocr.c ->
nano-mallocr.c redirection from the Makefile to the source files.
This allows for consistent object name usage regardless of the
configuration options used in case a machine dir wants to define
its own override.
Since we already set up _LIBC to indicate source files are building
for newlib, we don't need this malloc-specific symbol. Convert it
over to simplify the build a bit.
The overflow check in mEMALIGn erroneously checks for INT_MAX,
albeit the input parameter is size_t. Fix this to check for
__SIZE_MAX__ instead. Also, it misses to check the req against
adding the alignment before calling mALLOc.
While at it, add out-of-bounds checks to pvALLOc, nano_memalign,
nano_valloc, and Cygwin's (unused) dlpvalloc.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
This built-in function (available in both gcc and clang) is more
efficient and generates shorter code than open-coding the test.
Signed-off-by: Keith Packard <keithp@keithp.com>
- when calculating a correction to align next brk to page boundary,
ensure that the correction is less than a page size
- if allocating the correction fails, ensure that the top size is
set to brk + sbrk_size (minus any front alignment made)
Signed-off-by: Jeff Johnston <jjohnstn@redhat.com>
* libc/stdlib/mallocr.c: Include <limits.h>.
(request2size): Change macro to do
unsigned long comparisons and avoid signed overflow.
(mALLOc): Add overflow check for the number of bytes to allocate.
(rEALLOc): Ditto.
* Makefile.in: Regenerate.
* libc/include/_ansi.h (_EXFUN): Define specially for __CYGWIN__.
(_EXPARM): New macro for defining a function parameter.
* libc/include/stdlib.h: Use _EXPARM.
* libc/stdlib/mallocr.c: Don't build cfree for Cygwin.
Mike Frysinger
Corinna Vinschen
Keith Packard via Newlib
Jeff Johnston
Richard Sandiford
Alexandre Oliva
Matthew Green
Christopher Faylor