realloc functions check for recursion within the malloc code itself. In
a thread-safe library, the single spinlock ensures that no two threads
go inside the protected code at the same time. The thread implementation
is responsible for ensuring that the spinlock does in fact protect malloc.
There was a window of opportunity in which this was not the case. I'll fix
that with a commit RSN.
Our spinlock implementation allows a particular thread to obtain a lock
multiple times, but release the lock with a single unlock call. Since
we're detecting recursion, we know the lock is already owned by the
current thread in a previous call and must not be released in the
current call. This is really far too dependent on this particular
spinlock implementation, so I've added commented out calls to
THREAD_UNLOCK in the appropriate places. We can activate this code when
spinlock is taught to count each lock operation.
In some cases replace if (a == null) a = malloc(x); else a =
realloc(a, x); with simple reallocf(a, x). Per ANSI-C, this is
guaranteed to be the same thing.
I've been running these on my system here w/o ill effects for some
time. However, the CTM-express is at part 6 of 34 for the CAM
changes, so I've not been able to do a build world with the CAM in the
tree with these changes. Shouldn't impact anything, but...
when it returns NULL to indicate failure, it will also free the memory
that was passed to it, if that was non-null.
This does not change the semantics of realloc.
A second commit will be done to commit the conversion of those places in
the code that can safely use this to avoid memory leaks when confronted
with low memory situations.
Beaten-to-death-but-finally-approved-in: -current
but also assumes that they are 32-bits. This is one place where I don't
think it is appropriate to change 'long' to 'int'. I don't see why the
code couldn't be fixed so that using natural long variables does the
right thing. It's spaggetti code so it'll take some effort. Obviously
NetBSD thought so too because they change 'long' to 'int32_t' etc
and left it at that. As a temporary measure FreeBSD/Alpha can use the
NetBSD code and put this on the list of things to fix.
libc to determine if locking is required. This is needed in libc
for use with kernel threads, but until a thread is created, we don't
really want to bother locking things. The variable was added here
because the crt code calls exit(main()) so all programs will get the
variable.
a malloc. The signal handler creates a thread which requires a malloc...
For now, the only thing to do is to block signals. When we move user
pthreads to use the kernel threads, mutexes will be implemented in kernel
space and then malloc can revert.
This fixes bugs in the manual handling. abs.[cS] was handled too
specially and the wrong (.c) variant for each of div.[cS], labs.[cS]
and ldiv.[cS] was added to SRCS. This caused the .c variant to be
used if `depend' was made and the .S version to be used otherwise.
Dmitrij Tejblum <dima@tejblum.dnttm.rssi.ru>
Various cleanup from Keith Bostic
Reinstate calloc() as a separate funtion, in its own source/object file.
leave the manpage integrated with malloc.3 and friends. Too many things
were broken in this respect.
PR: 4002
Reviewed by: phk
Submitted by: Dmitrij Tejblum <dima@tejblum.dnttm.rssi.ru>
Submitted by: Keith Bostic <bostic@bostic.com>
Various portability and stylistic cleanups.
Kill MALLOC_STATS & the 'D' option.
Fix the 'V' option.
Major overhaul of the man-page.
You milage should not vary.
Reviewed by: Keith Bostic <bostic@bostic.com>
Submitted by: Keith Bostic <bostic@bostic.com>
implement (better) falback code inside srandomdev() itself.
Change return type from int to void (binary compatibility surprisely
achieved). Userland code will be changed soon.
Malloc cannot use pthread_mutex_init() to initialize a mutex because
the mutex initialization process does a malloc!
libc_r internals skip the malloc and assign an initializer to a static
structure and point the opaque type (pthread_mutex_t in this case) to
that structure. This is done on the assumption that the mutex will never
be destroyed. This style of initialization is only valid inside libc_r
because the structure that is assigned is opaque to the user.
This fix allows a simple program to get to main() again. 8-)
so that all these makefiles can be used to build libc_r too.
Added .if ${LIB} == "c" tests to restrict man page builds to libc
to avoid needlessly building them with libc_r too.
Split libc Makefile into Makefile and Makefile.inc to allow the
libc_r Makefile to include Makefile.inc too.
Back out a dubious Lite2 change to "optimise" getcwd() to look at $PWD
because it's potentially dangerous (think: symlink races). Move
realpath() back to it's original location, and remove getcwd_physical()
by renaming it back to getcwd() and zapping the original getcwd wrapper.
Noticed by: bde
The following commits already happened but the log message got lost:
Modified Files:
gen/Makefile.inc gen/getcwd.c stdlib/Makefile.inc
Removed Files:
gen/realpath.3
because it's potentially dangerous (think: symlink races). Move
realpath() back to it's original location, and remove getcwd_physical()
by renaming it back to getcwd() and zapping the original getcwd wrapper.
Noticed by: bde
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
Add progname to warning/error message layout. (joerg)
Remove inline assembler, no speed impact, not need for the obfuscation (bde)
Remove on the fly calculation of parameters, no longer critical.
Make D & U flags valid even if we don't support them.
Don't call imalloc until we're done initializing.
Zap contents on free() if we have "Junk" set. [*]
Various nitpicking.
[*] As a sideeffect of this change, if you are worried about
sensitive data lingering in memory, you can use the 'Junk' option
now to make sure phkmalloc zaps memory when it is returned. add
char * malloc_options = "J";
to your source. Obviously there is a performance impact.
Various neat features added. More documentation in the manpage.
If your machine has very little RAM, I guess that would be < 16M
these days :-(, you may want to try this:
ln -fs 'H<' /etc/malloc.conf
check the manpage.
as done after a quasi-recursive call to free() had modified what we
thought we knew about the last chunk of pages.
This bug manifested itself when I did a "make obj" from src/usr.sbin/lpr,
then make would coredump in the lpd directory.
in a bunch of man pages.
Use the correct .Bx (BSD UNIX) or .At (AT&T UNIX) macros
instead of explicitly specifying the version in the text
in a bunch of man pages.
by W.Richard Ste vens. EINTR handling suggested by bde@freebsd.org).
Code cleanup:
1. Add missing return type.
2. Replace 'union wait' by int.
3. Use Posix-style signal handling instead of signal().
4. Use fork() instead of deprecated vfork().
5. Block signals before fork()'ing, instead of after.
6. Return -1 if fork() fails, instead of 0.
7. Add EINTR handling for waitpid() call.
Also add claim of Posix conformance to man page.
in the main text of various man pages.
Thanks to Warner Losh for adding an option to manck to allow
it to scan the entire man page looking for bogus xrefs, instead
of just checking the SEE ALSO section.
