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2012-09-150.9.5 release notesv0.9.5Rich Felker-0/+32
2012-09-15fix syscall asm constraints for arm tooRich Felker-4/+4
no problems were detected so far, but the constraints seem to have been invalid just like the mips ones.
2012-09-15revert low rounds-count limits in crypt hashesRich Felker-4/+4
it was determined in discussion that these kind of limits are not sufficient to protect single-threaded servers against denial of service attacks from maliciously large round counts. the time scales simply vary too much; many users will want login passwords with rounds counts on a scale that gives decisecond latency, while highly loaded webservers will need millisecond latency or shorter. still some limit is left in place; the idea is not to protect against attacks, but to avoid the runtime of a single call to crypt being, for all practical purposes, infinite, so that configuration errors can be caught and fixed without bringing down whole systems. these limits are very high, on the order of minute-long runtimes for modest systems.
2012-09-15update mips cancellation-point syscall asm with 7-arg and r25 fixesRich Felker-2/+5
these fixes were already made to the normal syscall asm but not the cancellation point version.
2012-09-15fix buggy constraints in mips inline syscall asmRich Felker-2/+2
if same register is used for input/output, the compiler must be told. otherwise is generates random junk code that clobbers the result. in pure syscall-wrapper functions, nothing went wrong, but in more complex functions where register allocation is non-trivial, things broke badly.
2012-09-14workaround gcc got-register-reload performance problems in mallocRich Felker-4/+8
with this patch, the malloc in libc.so built with -Os is nearly the same speed as the one built with -O3. thus it solves the performance regression that resulted from removing the forced -O3 when building libc.so; now libc.so can be both small and fast.
2012-09-14remove forced -O3 from shared library CFLAGSRich Felker-1/+1
I originally added -O3 for shared libraries to counteract very bad behavior by GCC when building PIC code: it insists on reloading the GOT register in static functions that need it, even if the address of the function is never leaked from the translation unit and all local callers of the function have already loaded the GOT register. this measurably degrades performance in a few key areas like malloc. the inlining done at -O3 avoids the issue, but that's really not a good reason for overriding the user's choice of optimization level.
2012-09-14use vfork if possible in posix_spawnRich Felker-1/+3
vfork is implemented as the fork syscall (with no atfork handlers run) on archs where it is not available, so this change does not introduce any change in behavior or regression for such archs.
2012-09-13strsep is BSD|GNU, not GNU-only; it's originally from BSDRich Felker-1/+4
2012-09-13add O_PATH/O_SEARCH support to fcntl.hRich Felker-1/+9
I'm not 100% sure that Linux's O_PATH meets the POSIX requirements for O_SEARCH, but it seems very close if not perfect. and old kernels ignore it, so O_SEARCH will still work as desired as long as the caller has read permissions to the directory.
2012-09-11improve mips syscall asm constraints to use immediates, if possibleRich Felker-12/+21
by using the "ir" constraint (immediate or register) and the carefully constructed instruction addu $2,$0,%2 which can take either an immediate or a register for %2, the new inline asm admits maximal optimization with no register spillage to the stack when the compiler successfully performs constant propagration, but still works by allocating a register when the syscall number cannot be recognized as a constant. in the case of syscalls with 0-3 arguments it barely matters, but for 4-argument syscalls, using an immediate for the syscall number avoids creating a stack frame for the syscall wrapper function.
2012-09-10eliminate assumption that mips syscall restart preserves r25Rich Felker-23/+12
all past and current kernel versions have done so, but there seems to be no reason it's necessary and the sentiment from everyone I've asked has been that we should not rely on it. instead, use r7 (an argument register) which will necessarily be preserved upon syscall restart. however this only works for 0-3 argument syscalls, and we have to resort to the function call for 4-argument syscalls.
2012-09-10asm for memmove on i386 and x86_64Rich Felker-0/+36
for the sake of simplicity, I've only used rep movsb rather than breaking up the copy for using rep movsd/q. on all modern cpus, this seems to be fine, but if there are performance problems, there might be a need to go back and add support for rep movsd/q.
2012-09-10fix another ppoll issue (missing sigset_t size argument)Rich Felker-1/+1
2012-09-10reenable word-at-at-time copying in memmoveRich Felker-4/+27
before restrict was added, memove called memcpy for forward copies and used a byte-at-a-time loop for reverse copies. this was changed to avoid invoking UB now that memcpy has an undefined copying order, making memmove considerably slower. performance is still rather bad, so I'll be adding asm soon.
2012-09-10fix ppoll with null timeout argumentRich Felker-2/+2
2012-09-10add LIBCC (compiler runtime) logic and override to configureRich Felker-0/+7
this should both fix the issue with ARM needing -lgcc_eh (although that's really a bug in the libgcc build process that's causing considerable bloat, which should be fixed) and make it easier to build musl using clang/llvm in place of gcc. unfortunately I don't know a good way to detect and support pcc's -lpcc since it's not in pcc's default library search path...
2012-09-09add setdomainname syscall, fix getdomainname (previously a stub)Rich Felker-1/+18
2012-09-09mincore syscall wrapperRich Felker-0/+9
2012-09-09fix up lfs64 junk for preadv/pwritevRich Felker-2/+7
2012-09-09add preadv/pwritev syscall wrappersRich Felker-0/+35
2012-09-09fix typo introduced in poll.hRich Felker-1/+1
2012-09-09add linux ppoll syscall wrapperRich Felker-0/+19
2012-09-09reenable sync_file_range; should no longer break on mipsRich Felker-2/+2
2012-09-09add 7-arg syscall support for mipsRich Felker-4/+8
no syscalls actually use that many arguments; the issue is that some syscalls with 64-bit arguments have them ordered badly so that breaking them into aligned 32-bit half-arguments wastes slots with padding, and a 7th slot is needed for the last argument.
2012-09-09inline syscall support for armRich Felker-0/+53
most pure-syscall-wrapper functions compile to the smallest/simplest code possible (save r7 ; load syscall # ; svc 0 ; restore r7 ; tail call to __syscall_ret).
2012-09-09inline syscall support for mipsRich Felker-0/+57
this drastically reduces the size of some functions which are purely syscall wrappers. disabled for clang due to known bugs satisfying register constraints.
2012-09-09fix mips syscall_cp_asm code (saved register usage)Rich Felker-2/+2
2012-09-09fix broken mips syscall asmRich Felker-2/+2
this code was using $10 to save the syscall number, but $10 is not necessarily preserved by the kernel across syscalls. only mattered for syscalls that got interrupted by a signal and restarted. as far as i can tell, $25 is preserved by the kernel across syscalls.
2012-09-08disable sync_file_range for nowRich Felker-2/+3
something is wrong with the logic for the argument layout, resulting in compile errors on mips due to too many args to syscall... further information on how it's supposed to work will be needed before it can be reactivated.
2012-09-08syscall organization overhaulRich Felker-655/+420
now public syscall.h only exposes __NR_* and SYS_* constants and the variadic syscall function. no macros or inline functions, no __syscall_ret or other internal details, no 16-/32-bit legacy syscall renaming, etc. this logic has all been moved to src/internal/syscall.h with the arch-specific parts in arch/$(ARCH)/syscall_arch.h, and the amount of arch-specific stuff has been reduced to a minimum. changes still need to be reviewed/double-checked. minimal testing on i386 and mips has already been performed.
2012-09-08add acct syscall source file, omitted in last syscalls commitRich Felker-0/+9
2012-09-08add acct, accept4, setns, and dup3 syscalls (linux extensions)Rich Felker-0/+113
based on patch by Justin Cormack
2012-09-08add IPPROTO_HOPOPTS to in.hRich Felker-0/+1
2012-09-08add IPPROTO_MAX to in.hRich Felker-0/+1
2012-09-08fix redundant _Noreturn def in err.hRich Felker-7/+1
not sure why this was missed in the earlier commit.
2012-09-08remove all remaining redundant __restrict/__inline/_Noreturn defsRich Felker-76/+14
2012-09-08sysmacros major/minor: result should have type unsigned int, not dev_tRich Felker-2/+2
2012-09-08add linux tee syscallRich Felker-0/+9
2012-09-08add linux sync_file_range syscallRich Felker-0/+20
2012-09-08move fallocate syscall wrapper to linux-specific syscalls dirRich Felker-0/+0
2012-09-08add linux readahead syscallRich Felker-0/+9
2012-09-08add fallocate (nonstandardized) functionRich Felker-0/+12
this is equivalent to posix_fallocate except that it has an extra mode/flags argument to control its behavior, and stores the error in errno rather than returning an error code.
2012-09-08fix broken fallocate syscall in posix_fallocateRich Felker-1/+1
the syscall takes an extra flag argument which should be zero to meet the POSIX requirements.
2012-09-08add timerfd interfaces (untested)Rich Felker-0/+35
2012-09-08add stdnoreturn.h (C11)Rich Felker-0/+5
features.h contains the fallback logic for pre-C11 compilers
2012-09-07TCP_* is in the reserved namespace for tcp.h; make use of thatRich Felker-3/+4
2012-09-07remove unneeded judgemental commentary from ftw.hRich Felker-4/+0
2012-09-07default features: make musl usable without feature test macrosRich Felker-129/+102
the old behavior of exposing nothing except plain ISO C can be obtained by defining __STRICT_ANSI__ or using a compiler option (such as -std=c99) that predefines it. the new default featureset is POSIX with XSI plus _BSD_SOURCE. any explicit feature test macros will inhibit the default. installation docs have also been updated to reflect this change.
2012-09-07add clang-compatible thread-pointer code for mipsRich Felker-0/+4
clang does not presently support the "v" constraint we want to use to get the result from $3, and trying to use register...__asm__("$3") to do the same invokes serious compiler bugs. so for now, i'm working around the issue with an extra temp register and putting $3 in the clobber list instead of using it as output. when the bugs in clang are fixed, this issue should be revisited to generate smaller/faster code like what gcc gets.