| Commit message (Expand) | Author | Files | Lines |
|---|
| 2012-11-04 | mips cache flush/ctl syscall support and header | Rich Felker | 2 | -0/+40 |
| 2012-11-01 | remove one unnecessary static var from dynamic linker | Rich Felker | 1 | -2/+2 |
| 2012-11-01 | fix more unused variable warnings•••some of these were coming from stdio functions locking files without
unlocking them. I believe it's useful for this to throw a warning, so
I added a new macro that's self-documenting that the file will never
be unlocked to avoid the warning in the few places where it's wrong.
| Rich Felker | 4 | -6/+5 |
| 2012-11-01 | fix unused variable warnings | Rich Felker | 2 | -2/+1 |
| 2012-11-01 | avoid breakage if somebody wrongly defines empty feature test macros | Rich Felker | 2 | -3/+3 |
| 2012-10-31 | add dl_iterate_phdr interface•••patches by Alex Caudill (npx). the dynamic-linked version is almost
identical to the final submitted patch; I just added a couple missing
lines for saving the phdr address when the dynamic linker is invoked
directly to run a program, and removed a couple to avoid introducing
another unnecessary type. the static-linked version is based on npx's
draft. it could use some improvements which are contingent on the
startup code saving some additional information for later use.
| Rich Felker | 3 | -7/+114 |
| 2012-10-28 | system is a cancellation point•••ideally, system would also be cancellable while running the external
command, but I cannot find any way to make that work without either
leaking zombie processes or introducing behavior that is far outside
what the standard specifies. glibc handles cancellation by killing the
child process with SIGKILL, but this could be unsafe in that it could
leave the data being manipulated by the command in an inconsistent
state.
| Rich Felker | 1 | -0/+3 |
| 2012-10-28 | release notes for 0.9.7 | Rich Felker | 1 | -0/+31 |
| 2012-10-28 | fix shmdt syscall calling convention on old archs | Rich Felker | 1 | -1/+1 |
| 2012-10-27 | separate getc/putc from fgetc/fputc•••for conformance, two functions should not have the same address. a
conforming program could use the addresses of getc and fgetc in ways
that assume they are distinct. normally i would just use a wrapper,
but these functions are so small and performance-critical that an
extra layer of function call could make the one that's a wrapper
nearly twice as slow, so I'm just duplicating the code instead.
| Rich Felker | 4 | -6/+25 |
| 2012-10-26 | update documentation | Rich Felker | 2 | -32/+66 |
| 2012-10-26 | further pcc fixes in configure•••-lpcc only works if -nostdlib is not passed, so it's useless. instead,
use -print-file-name to look up the full pathname for libpcc.a, and
check whether that succeeds before trying to link with the result.
also, silence pcc's junk printed on stdout during tests.
| Rich Felker | 1 | -3/+4 |
| 2012-10-26 | add support for detecting pcc's compiler runtime•••in old versions of pcc, the directory containing libpcc.a was not in
the library path, and other options like -print-file-name may have
been needed to locate it. however, -print-file-name itself seems to
have been added around the same time that the directory was added to
the search path, and moreover, I see no evidence that older versions
of pcc are capable of building a working musl shared library. thus, it
seems reasonable to just test whether -lpcc is accepted.
| Rich Felker | 1 | -0/+1 |
| 2012-10-25 | use explicit visibility to optimize a few hot-path function calls•••on x86 and some other archs, functions which make function calls which
might go through a PLT incur a significant overhead cost loading the
GOT register prior to making the call. this load is utterly useless in
musl, since all calls are bound at library-creation time using
-Bsymbolic-functions, but the compiler has no way of knowing this, and
attempts to set the default visibility to protected have failed due to
bugs in GCC and binutils.
this commit simply manually assigns hidden/protected visibility, as
appropriate, to a few internal-use-only functions which have many
callers, or which have callers that are hot paths like getc/putc. it
shaves about 5k off the i386 libc.so with -Os. many of the
improvements are in syscall wrappers, where the benefit is just size
and performance improvement is unmeasurable noise amid the syscall
overhead. however, stdio may be measurably faster.
if in the future there are toolchains that can do the same thing
globally without introducing linking bugs, it might be worth
considering removing these workarounds.
| Rich Felker | 3 | -11/+13 |
| 2012-10-25 | configure: test not just compiling but linking with -march/-mtune•••pcc wrongly passes any option beginning with -m to the linker, and
will break at link time if these options were added to CFLAGS. testing
linking lets us catch this at configure time and skip them.
| Rich Felker | 1 | -2/+2 |
| 2012-10-24 | correct locking in stdio functions that tried to be lock-free•••these functions must behave as if they obtain the lock via flockfile
to satisfy POSIX requirements. since another thread can provably hold
the lock when they are called, they must wait to obtain the lock
before they can return, even if the correct return value could be
obtained without locking. in the case of fclose and freopen, failure
to do so could cause correct (albeit obscure) programs to crash or
otherwise misbehave; in the case of feof, ferror, and fwide, failure
to obtain the lock could sometimes return incorrect results. in any
case, having these functions proceed and return while another thread
held the lock was wrong.
| Rich Felker | 6 | -16/+36 |
| 2012-10-24 | greatly improve freopen behavior•••1. don't open /dev/null just as a basis to copy flags; use shared
__fmodeflags function to get the right file flags for the mode.
2. handle the case (probably invalid, but whatever) case where the
original stream's file descriptor was closed; previously, the logic
re-closed it.
3. accept the "e" mode flag for close-on-exec; update dup3 to fallback
to using dup2 so we can simply call __dup3 instead of putting fallback
logic in freopen itself.
| Rich Felker | 5 | -17/+41 |
| 2012-10-24 | remove useless failure-check from freopen (can't happen) | Rich Felker | 1 | -2/+2 |
| 2012-10-22 | simplify logic in stpcpy; avoid copying first aligned byte twice•••gcc seems to be generating identical or near-identical code for both
versions, but the newer code is more expressive of what it's doing.
| Rich Felker | 1 | -4/+4 |
| 2012-10-21 | fix issues with wait constants in stdlib.h•••the W* namespace is not reserved, so the nonstandard ones must be
moved under extension features. also WNOHANG and WUNTRACED were
missing.
| Rich Felker | 2 | -6/+5 |
| 2012-10-21 | as an extension, have putenv("VAR") behave as unsetenv("VAR")•••the behavior of putenv is left undefined if the argument does not
contain an equal sign, but traditional implementations behave this way
and gnulib replaces putenv if it doesn't do this.
| Rich Felker | 1 | -5/+5 |
| 2012-10-21 | accept "nan(n-char-sequence)" in strtod/scanf functions•••this will prevent gnulib from wrapping our strtod to handle this
useless feature.
| Rich Felker | 1 | -1/+19 |
| 2012-10-21 | fix copy/paste error in popen changes that broke signals•••signal mask was not being restored after fork, but instead blocked again.
| Rich Felker | 1 | -1/+1 |
| 2012-10-21 | complex: make _Complex_I work with gcc -std=c99 -pedantic-errors | nsz | 1 | -0/+4 |
| 2012-10-19 | support looking up thread-local objects with dlsym | Rich Felker | 1 | -0/+6 |
| 2012-10-19 | fix breakage in dlsym for looking up RTLD_DEFAULT, etc.•••this was broken during the early dynamic-linked TLS commits, which
rearranged some of the code for handling new relocation types.
| Rich Felker | 1 | -2/+5 |
| 2012-10-19 | fix struct stat size/padding on microblaze | Rich Felker | 1 | -1/+2 |
| 2012-10-19 | fix usage of locks with vfork•••__release_ptc() is only valid in the parent; if it's performed in the
child, the lock will be unlocked early then double-unlocked later,
corrupting the lock state.
| Rich Felker | 3 | -3/+4 |
| 2012-10-19 | fix crashes in static-linked multithreaded programs without TLS | Rich Felker | 1 | -0/+2 |
| 2012-10-19 | fix order of syscall args for microblaze clone syscall•••with this commit, based on testing with patches to qemu which are not
yet upstream,
| Rich Felker | 1 | -3/+2 |
| 2012-10-18 | use $CC rather than "$CC" in configure script•••this is necessary to allow $CC with arguments in it
| Rich Felker | 1 | -4/+4 |
| 2012-10-18 | inline syscalls for microblaze | Rich Felker | 1 | -0/+97 |
| 2012-10-18 | ensure microblaze __set_thread_area returns success•••since it did not set the return-value register, the caller could
wrongly interpret this as failure.
| Rich Felker | 1 | -1/+2 |
| 2012-10-18 | better support for reverse-endian variants of arm/mips/microblaze•••these macros are supported by more compilers
| Rich Felker | 3 | -0/+12 |
| 2012-10-18 | avoid raising spurious division-by-zero exception in printf | Rich Felker | 1 | -1/+1 |
| 2012-10-18 | floating point environment/exceptions support for mips | Rich Felker | 2 | -3/+73 |
| 2012-10-18 | fix parent-memory-clobber in posix_spawn (environ) | Rich Felker | 3 | -9/+17 |
| 2012-10-18 | overhaul system() and popen() to use vfork; fix various related bugs•••since we target systems without overcommit, special care should be
taken that system() and popen(), like posix_spawn(), do not fail in
processes whose commit charges are too high to allow ordinary forking.
this in turn requires special precautions to ensure that the parent
process's signal handlers do not end up running in the shared-memory
child, where they could corrupt the state of the parent process.
popen has also been updated to use pipe2, so it does not have a
fd-leak race in multi-threaded programs. since pipe2 is missing on
older kernels, (non-atomic) emulation has been added.
some silly bugs in the old code should be gone too.
| Rich Felker | 4 | -56/+110 |
| 2012-10-18 | fix (hopefully; untested) completely broken/incomplete microblaze sigsetjmp | Rich Felker | 1 | -3/+12 |
| 2012-10-17 | fix microblaze asm relocations for shared libc•••only @PLT relocations are considered functions for purposes of
-Bsymbolic-functions, so always use @PLT. it should not hurt in the
static-linked case.
| Rich Felker | 4 | -6/+6 |
| 2012-10-17 | assert() is supposed to have type void | Rich Felker | 1 | -1/+1 |
| 2012-10-15 | add memmem function (gnu extension)•••based on strstr. passes gnulib tests and a few quick checks of my own.
| Rich Felker | 2 | -0/+149 |
| 2012-10-15 | microblaze TLS relocation support, completely untested | Rich Felker | 2 | -1/+14 |
| 2012-10-15 | add support for TLS variant I, presently needed for arm and mips•••despite documentation that makes it sound a lot different, the only
ABI-constraint difference between TLS variants II and I seems to be
that variant II stores the initial TLS segment immediately below the
thread pointer (i.e. the thread pointer points to the end of it) and
variant I stores the initial TLS segment above the thread pointer,
requiring the thread descriptor to be stored below. the actual value
stored in the thread pointer register also tends to have per-arch
random offsets applied to it for silly micro-optimization purposes.
with these changes applied, TLS should be basically working on all
supported archs except microblaze. I'm still working on getting the
necessary information and a working toolchain that can build TLS
binaries for microblaze, but in theory, static-linked programs with
TLS and dynamic-linked programs where only the main executable uses
TLS should already work on microblaze.
alignment constraints have not yet been heavily tested, so it's
possible that this code does not always align TLS segments correctly
on archs that need TLS variant I.
| Rich Felker | 12 | -17/+79 |
| 2012-10-15 | block uid/gid changes during posix_spawn•••usage of vfork creates a situation where a process of lower privilege
may momentarily have write access to the memory of a process of higher
privilege.
consider the case of a multi-threaded suid program which is calling
posix_spawn in one thread while another thread drops the elevated
privileges then runs untrusted (relative to the elevated privilege)
code as the original invoking user. this untrusted code can then
potentially modify the data the child process will use before calling
exec, for example changing the pathname or arguments that will be
passed to exec.
note that if vfork is implemented as fork, the lock will not be held
until the child execs, but since memory is not shared it does not
matter.
| Rich Felker | 1 | -0/+10 |
| 2012-10-14 | fix overlap of thread stacks with thread tls segments | Rich Felker | 1 | -2/+1 |
| 2012-10-14 | fix main program TLS alignment for dynamic-linked programs•••this change brings the behavior in line with the static-linked code,
which seems to be correct.
| Rich Felker | 1 | -6/+5 |
| 2012-10-13 | workaround broken hidden-visibility handling in pcc•••with this change, pcc-built musl libc.so seems to work correctly. the
problem is that pcc generates GOT lookups for external-linkage symbols
even if they are hidden, rather than using GOT-relative addressing.
the entire reason we're using hidden visibility on the __libc object
is to make it accessible prior to relocations -- not to mention
inexpensive to access. unfortunately, the workaround makes it even
more expensive on pcc.
when the pcc issue is fixed, an appropriate version test should be
added so new pcc can use the much more efficient variant.
| Rich Felker | 1 | -1/+1 |
| 2012-10-13 | ensure pointer decay in inline-asm arg for i386 syscall6•••this is actually a rather subtle issue: do arrays decay to pointers
when used as inline asm args? gcc says yes, but currently pcc says no.
hopefully this discrepency in pcc will be fixed, but since the
behavior is not clearly defined anywhere I can find, I'm using an
explicit operation to cause the decay to occur.
| Rich Felker | 1 | -1/+1 |
| 2012-10-13 | fix namespace clash (libc) in dynlink.c•••this makes it so the #undef libc and __libc name are no longer needed,
which were problematic because the "accessor function" mode for
accessing the libc struct could not be used, breaking build on any
compiler without (working) visibility.
| Rich Felker | 1 | -14/+13 |
