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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.
2012-09-15fix 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.
2012-09-13add O_PATH/O_SEARCH support to fcntl.hRich Felker-0/+8
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,$0,%2 which can take either an immediate or a register for %2, the new inline asm admits maximal optimization with no register spillage to the stack when the compiler successfully performs constant propagration, but still works by allocating a register when the syscall number cannot be recognized as a constant. in the case of syscalls with 0-3 arguments it barely matters, but for 4-argument syscalls, using an immediate for the syscall number avoids creating a stack frame for the syscall wrapper function.
2012-09-10eliminate assumption that mips syscall restart preserves r25Rich Felker-23/+12
all past and current kernel versions have done so, but there seems to be no reason it's necessary and the sentiment from everyone I've asked has been that we should not rely on it. instead, use r7 (an argument register) which will necessarily be preserved upon syscall restart. however this only works for 0-3 argument syscalls, and we have to resort to the function call for 4-argument syscalls.
2012-09-09inline syscall support for armRich Felker-0/+53
most pure-syscall-wrapper functions compile to the smallest/simplest code possible (save r7 ; load syscall # ; svc 0 ; restore r7 ; tail call to __syscall_ret).
2012-09-09inline syscall support for mipsRich Felker-0/+57
this drastically reduces the size of some functions which are purely syscall wrappers. disabled for clang due to known bugs satisfying register constraints.
2012-09-08syscall organization overhaulRich Felker-632/+282
now public syscall.h only exposes __NR_* and SYS_* constants and the variadic syscall function. no macros or inline functions, no __syscall_ret or other internal details, no 16-/32-bit legacy syscall renaming, etc. this logic has all been moved to src/internal/syscall.h with the arch-specific parts in arch/$(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, accept4, setns, and dup3 syscalls (linux extensions)Rich Felker-0/+3
based on patch by Justin Cormack
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.
2012-09-02avoid "inline" in public headers for strict c89 compatibilityRich Felker-35/+35
while musl itself requires a c99 compiler, some applications insist on being compiled with c89 compilers, and use of "inline" in the headers was breaking them. much of this had been avoided already by just skipping the inline keyword in pre-c99 compilers or modes, but this new unified solution is cleaner and may/should result in better code generation in the default gcc configuration.
2012-08-11avoid need for -march=mips2 to compile mips atomic.h asmRich Felker-0/+8
linux guarantees ll/sc are always available. on mips1, they will be emulated by the kernel. thus they are part of the linux mips1 abi and safe to use.
2012-08-10use int instead of long for ptrdiff_t on all 32-bit archsRich Felker-2/+2
this is needed to match the underlying "ABI" standards. it's not really an ABI issue since the binary representations are the same, but having the wrong type can lead to errors when the type arising from a difference-of-pointers expression does not match the defined type of ptrdiff_t. most of the problems affect C++, not C.
2012-08-10fix incorrect ptrdiff_t type on mipsRich Felker-1/+1
2012-08-09add defines for number of sigset_t bytes syscalls expectRich Felker-0/+8
yet another gratuitous mips incompatibility...
2012-08-07further fixes for mips ioctl.h headerRich Felker-4/+4
untested; hopefully it's right now
2012-08-07fix another mips gratuitous-incompatibility bug: ioctl numbersRich Felker-2/+2
2012-08-05fix socket.h on mipsRich Felker-0/+3
why does mips have to be gratuitously incompatible in every possible imaginable way?
2012-08-05more stuff lost committing mips dynamic linkerRich Felker-2/+2
2012-08-05mips dynamic linker supportRich Felker-3/+53
not heavily tested, but the basics are working. the basic concept is that the dynamic linker entry point code invokes a pure-PIC (no global accesses) C function in reloc.h to perform the early GOT relocations needed to make the dynamic linker itself functional, then invokes __dynlink like on other archs. since mips uses some ugly arch-specific hacks to optimize relocating the GOT (rather than just using the normal DT_REL[A] tables like on other archs), the dynamic linker has been modified slightly to support calling arch-specific relocation code in reloc.h. most of the actual mips-specific behavior was developed by reading the output of readelf on libc.so and simple executable files. i could not find good reference information on which relocation types need to be supported or their semantics, so it's possible that some legitimate usage cases will not work yet.
2012-07-22add floating point register saving/restoring to mips setjmp/longjmpRich Felker-1/+1
also fix the alignment of jmp_buf to meet the abi. linux always emulates fpu on mips if it's not present, so enabling this code unconditionally is "safe" but may be slow. in the long term it may be preferable to find a way to disable it on soft float builds.
2012-07-12fix broken mips a_fetch_addRich Felker-7/+7
sc was overwriting the result
2012-07-12mipsel (little endian) supportRich Felker-1/+1
the fields in the mcontext_t are long long (for no good reason) even on 32-bit mips, so the offset of the instruction pointer (as a word) varies depending on endianness.
2012-07-12workaround another sendmsg kernel bug on 64-bit machinesRich Felker-0/+29
the kernel wrongly expects the cmsg length field to be size_t instead of socklen_t. in order to work around the issue, we have to impose a length limit and copy to a local buffer. the length limit should be more than sufficient for any real-world use; these headers are only used for passing file descriptors and permissions between processes over unix sockets.
2012-07-12fix redef of sigprocmask constants on mipsRich Felker-0/+3
this fix is easier than trying to reorder the header stuff
2012-07-12more mips bits-header fixesRich Felker-2/+6
signal handling was very broken because of this
2012-07-12fix mips syscalls with long long argsRich Felker-1/+1
like arm, mips requires 64-bit arguments to be "aligned" on an even register boundary.
2012-07-12fix mips mcontext_t structure sizeRich Felker-1/+5
otherwise offs in ucontext_t will be wrong, and break code that inspects or modifies the signal makes (including cancellation code).
2012-07-11fix MAP_ANONYMOUS value for mips, remove cruft copied from i386Rich Felker-2/+1
2012-07-11initial version of mips (o32) port, based on work by Richard Pennington (rdp)Rich Felker-0/+2037
basically, this version of the code was obtained by starting with rdp's work from his ellcc source tree, adapting it to musl's build system and coding style, auditing the bits headers for discrepencies with kernel definitions or glibc/LSB ABI or large file issues, fixing up incompatibility with the old binutils from aboriginal linux, and adding some new special cases to deal with the oddities of sigaction and pipe syscall interfaces on mips. at present, minimal test programs work, but some interfaces are broken or missing. threaded programs probably will not link.
2012-07-10support -mfpmath=387 on x86_64Rich Felker-0/+4
apparently somebody wants this for something... and it doesn't hurt.
2012-07-10fix wrong value of FLT_EVAL_METHOD for x86_64Rich Felker-1/+1
2012-07-08make arm syscalls (still non-inline) more efficientRich Felker-6/+6
no need to pass zero for unused arguments; just omit them.
2012-07-08remove little-endian assumption from arm atomic.hRich Felker-4/+6
this hidden endian dependency had left big endian arm badly broken.
2012-07-03jmp_buf overhaul fixing several issuesRich Felker-3/+3
on arm, the location of the saved-signal-mask flag and mask were off by one between sigsetjmp and siglongjmp, causing incorrect behavior restoring the signal mask. this is because the siglongjmp code assumed an extra slot was in the non-sig jmp_buf for the flag, but arm did not have this. now, the extra slot is removed for all archs since it was useless. also, arm eabi requires jmp_buf to have 8-byte alignment. we achieve that using long long as the type rather than with non-portable gcc attribute tags.
2012-06-23update syscall defs to latest kernel onesRich Felker-0/+38
patch submitted by Kristian L. <email@thexception.net>
2012-06-20proper error handling for fcntl F_GETOWN on modern kernelsRich Felker-0/+9
on old kernels, there's no way to detect errors; we must assume negative syscall return values are pgrp ids. but if the F_GETOWN_EX fcntl works, we can get a reliable answer.
2012-05-24fix arm syscall.h to reflect which syscalls actually exist (on EABI)Rich Felker-22/+0
2012-05-22fix missing _BSD_SOURCE support in bits/*.hRich Felker-12/+12
this is actually rather ugly, and would get even uglier if we ever want to support further feature test macros. at some point i may factor the bits headers into separate files for C base, POSIX base, and nonstandard extensions (the only distinctions that seem to matter now) and then the logic for which to include can go in the main header rather than being duplicated for each arch. the downside of this is that it would result in more files having to be opened during compilation, so as long as the ugliness does not grow, i'm inclined to leave it alone for now.
2012-04-29fix float_t and double_t defs on x86 when -mfpmath=sse -msse2 is usedRich Felker-0/+5
2012-04-27support FLT_EVAL_METHOD changing on x86 with gcc -msse2 -mfpmath=sseRich Felker-0/+4
if the compiler provides a value, use it; otherwise fallback to the platform default (2).
2012-04-24use signed char rather than plain char for int8_tRich Felker-12/+12
otherwise this BADLY breaks if -funsigned-char is passed to gcc
2012-04-15move F_DUPFD_CLOEXEC out of bitsRich Felker-6/+0
fcntl values 1024 and up are universal, arch-independent. later I'll add some of the other linux-specific ones for notify, leases, pipe size, etc. here too.
2012-04-15add F_SETSIG and F_GETSIG (linux specific) to fcntl.hRich Felker-0/+6
F_* is in the reserved namespace so no feature test is needed
2012-04-04work around nasty gcc bug in the i386 syscall asmRich Felker-4/+4
when the "r" (register) constraint is used to let gcc choose a register, gcc will sometimes assign the same register that was used for one of the other fixed-register operands, if it knows the values are the same. one common case is multiple zero arguments to a syscall. this horribly breaks the intended usage, which is swapping the GOT pointer from ebx into the temp register and back to perform the syscall. presumably there is a way to fix this with advanced usage of register constaints on the inline asm, but having bad memories about hellish compatibility issues with different gcc versions, for the time being i'm just going to hard-code specific registers to be used. this may hurt the compiler's ability to optimize, but it will fix serious miscompilation issues. so far the only function i know what compiled incorrectly is getrlimit.c, and naturally the bug only applies to shared (PIC) builds, but it may be more extensive and may have gone undetected..
2012-03-21fix DECIMAL_DIG definitionsRich Felker-0/+6
DECIMAL_DIG is not the same as LDBL_DIG type_DIG is the maximimum number of decimal digits that can survive a round trip from decimal to type and back to decimal. DECIMAL_DIG is the minimum number of decimal digits required in order for any floating point type to survive the round trip to decimal and back, and it is generally larger than LDBL_DIG. since the exact formula is non-trivial, and defining it larger than necessary may be legal but wasteful, just define the right value in bits/float.h.
2012-02-25use __attribute__((const)) on arm __pthread_self functionRich Felker-1/+3
2012-02-15add float_t and double_t to math.hRich Felker-0/+9
2012-02-09replace bad cancellation cleanup abi with a sane oneRich Felker-37/+0
the old abi was intended to duplicate glibc's abi at the expense of being ugly and slow, but it turns out glib was not even using that abi except on non-gcc-compatible compilers (which it doesn't even support) and was instead using an exceptions-in-c/unwind-based approach whose abi we could not duplicate anyway without nasty dwarf2/unwind integration. the new abi is copied from a very old glibc abi, which seems to still be supported/present in current glibc. it avoids all unwinding, whether by sjlj or exceptions, and merely maintains a linked list of cleanup functions to be called from the context of pthread_exit. i've made some care to ensure that longjmp out of a cleanup function should work, even though it is not required to. this change breaks abi compatibility with programs which were using pthread cancellation, which is unfortunate, but that's why i'm making the change now rather than later. considering that most pthread features have not been usable until recently anyway, i don't see it as a major issue at this point.
2012-01-20add prlimit syscall wrapperRich Felker-0/+2