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2012-10-15add support for TLS variant I, presently needed for arm and mipsRich Felker-1/+2
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.
2012-10-13ensure pointer decay in inline-asm arg for i386 syscall6Rich Felker-1/+1
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.
2012-10-11i386 vsyscall support (vdso-provided sysenter/syscall instruction based)Rich Felker-66/+7
this doubles the performance of the fastest syscalls on the atom I tested it on; improvement is reportedly much more dramatic on worst-case cpus. cannot be used for cancellable syscalls.
2012-10-04dynamic-linked TLS support for everything but dlopen'd libsRich Felker-1/+21
currently, only i386 is tested. x86_64 and arm should probably work. the necessary relocation types for mips and microblaze have not been added because I don't understand how they're supposed to work, and I'm not even sure if it's defined yet on microblaze. I may be able to reverse engineer the requirements out of gcc/binutils output.
2012-09-22fix broken semctl on systems that don't use IPC_64 flagRich Felker-0/+2
not tested on mips and arm; they may still be broken. x86_64 should be ok now.
2012-09-15add O_EXEC open modeRich Felker-0/+1
the linux O_PATH mode provides the necessary semantics for both the O_SEARCH and O_EXEC modes defined and required by POSIX 2008.
2012-09-13add O_PATH/O_SEARCH support to fcntl.hRich Felker-0/+2
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.
2012-09-08syscall organization overhaulRich Felker-286/+136
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
2012-09-02avoid "inline" in public headers for strict c89 compatibilityRich Felker-14/+14
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.
2012-08-10use int instead of long for ptrdiff_t on all 32-bit archsRich Felker-1/+1
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.
2012-08-09add defines for number of sigset_t bytes syscalls expectRich Felker-0/+2
yet another gratuitous mips incompatibility...
2012-07-12workaround another sendmsg kernel bug on 64-bit machinesRich Felker-0/+7
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.
2012-07-03jmp_buf overhaul fixing several issuesRich Felker-1/+1
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/+16
patch submitted by Kristian L. <email@thexception.net>
2012-06-20proper error handling for fcntl F_GETOWN on modern kernelsRich Felker-0/+3
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.
2012-05-22fix missing _BSD_SOURCE support in bits/*.hRich Felker-4/+4
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-4/+4
otherwise this BADLY breaks if -funsigned-char is passed to gcc
2012-04-15move F_DUPFD_CLOEXEC out of bitsRich Felker-2/+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/+2
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/+2
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.
2012-02-15add float_t and double_t to math.hRich Felker-0/+3
2012-02-09replace bad cancellation cleanup abi with a sane oneRich Felker-25/+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
2011-10-15don't define wchar_t on c++Rich Felker-0/+2
it's a keyword in c++ (wtf). i'm not sure this is the cleanest solution; it might be better to avoid ever defining __NEED_wchar_t on c++. but in any case, this works for now.
2011-09-22cleanup/debloat i386 user.hRich Felker-43/+11
2011-09-21update syscalls with off_t arguments to handle argument alignment, if neededRich Felker-1/+2
the arm syscall abi requires 64-bit arguments to be aligned on an even register boundary. these new macros facilitate meeting the abi requirement without imposing significant ugliness on the code.
2011-09-19fix the definition of struct statvfs to match lsb abiRich Felker-15/+6
at the same time, make struct statfs match the traditional definition and make it more useful, especially the fsid_t stuff.
2011-09-19cleanup redundancy in bits/signal.h versionsRich Felker-122/+10
2011-09-19fix the type of wchar_t on arm; support wchar_t varying with archRich Felker-0/+4
really wchar_t should never vary, but the ARM EABI defines it as an unsigned 32-bit int instead of a signed one, and gcc follows this nonsense. thus, to give a conformant environment, we have to follow (otherwise L""[0] and L'\0' would be 0U rather than 0, but the application would be unaware due to a mismatched definition for WCHAR_MIN and WCHAR_MAX, and Bad Things could happen with respect to signed/unsigned comparisons, promotions, etc.). fortunately no rules are imposed by the C standard on the relationship between wchar_t and wint_t, and WEOF has type wint_t, so we can still make wint_t always-signed and use -1 for WEOF.
2011-09-18cleanup more bits cruft (sysmacros and socket)Rich Felker-206/+0
2011-09-18more bits junk (tcp.h)Rich Felker-1/+0
2011-09-18move invariant netinet/in.h stuff out of bits/in.hRich Felker-145/+0
2011-08-23security hardening: ensure suid programs have valid stdin/out/errRich Felker-0/+5
this behavior (opening fds 0-2 for a suid program) is explicitly allowed (but not required) by POSIX to protect badly-written suid programs from clobbering files they later open. this commit does add some cost in startup code, but the availability of auxv and the security flag will be useful elsewhere in the future. in particular auxv is needed for static-linked vdso support, which is still waiting to be committed (sorry nik!)
2011-08-06ensure the compiler does not move around thread-register-based readsRich Felker-1/+1
if gcc decided to move this across a conditional that checks validity of the thread register, an invalid thread-register-based read could be performed and raise sigsegv.
2011-07-21socket headers macro adjustment - workaround for buggy programsRich Felker-1/+1
some program was undefining AF_NETLINK and thereby breaking AF_ROUTE...
2011-06-25fix some symbol resolution issues in dynamic linkerRich Felker-0/+1
1. search was wrongly beginning with lib itself rather than dso head 2. inconsistent resolution of function pointers for functions in plt
2011-06-25move all limits that don't vary out of bits/limits.h, into main limits.hRich Felker-26/+1
2011-06-25proper path searching for dynamic linkerRich Felker-0/+2
first, use $LD_LIBRARY_PATH unless suid. if that fails, read path from /etc/ld-musl-$ARCH.path and fallback to a builtin default.
2011-06-18experimental dynamic linker!Rich Felker-0/+26
some notes: - library search path is hard coded - x86_64 code is untested and may not work - dlopen/dlsym is not yet implemented - relocations in read-only memory won't work
2011-06-14__syscall5 inline is having trouble with PIC; just use the function for nowRich Felker-0/+7
2011-06-07use __WCHAR_TYPE__ on i386 if it is definedRich Felker-0/+4
unfortunately traditional i386 practice was to use "long" rather than "int" for wchar_t, despite the latter being much more natural and logical. we followed this practice, but it seems some compilers (clang and maybe certain gcc builds or others too..?) have switched to using int, resulting in spurious pointer type mismatches when L"..." wide strings are used. the best solution I could find is to use the compiler's definition of wchar_t if it exists, and otherwise fallback to the traditional definition. there's no point in duplicating this approach on 64-bit archs, as their only 32-bit type is int.
2011-04-27use compiler builtins for variadic macros when availableRich Felker-0/+5
this slightly cuts down on the degree musl "fights with" gcc, but more importantly, it fixes a critical bug when gcc inlines a variadic function and optimizes out the variadic arguments due to noticing that they were "not used" (by __builtin_va_arg). we leave the old code in place if __GNUC__ >= 3 is false; it seems like it might be necessary at least for tinycc support and perhaps if anyone ever gets around to fixing gcc 2.95.3 enough to make it work..
2011-04-27add word-sized ctz function to atomic.hRich Felker-2/+8
strictly speaking this and a few other ops should be factored into asm.h or the file should just be renamed to asm.h, but whatever. clean it up someday.
2011-04-21move wait.h macros out of bits. they do not vary.Rich Felker-23/+0
2011-04-20namespace fixes for sys/mman.hRich Felker-15/+15
2011-04-20add syscall wrappers for posix_fadvise, posix_fallocateRich Felker-0/+4