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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
2011-04-17overhaul pthread cancellationRich Felker-6/+8
this patch improves the correctness, simplicity, and size of cancellation-related code. modulo any small errors, it should now be completely conformant, safe, and resource-leak free. the notion of entering and exiting cancellation-point context has been completely eliminated and replaced with alternative syscall assembly code for cancellable syscalls. the assembly is responsible for setting up execution context information (stack pointer and address of the syscall instruction) which the cancellation signal handler can use to determine whether the interrupted code was in a cancellable state. these changes eliminate race conditions in the previous generation of cancellation handling code (whereby a cancellation request received just prior to the syscall would not be processed, leaving the syscall to block, potentially indefinitely), and remedy an issue where non-cancellable syscalls made from signal handlers became cancellable if the signal handler interrupted a cancellation point. x86_64 asm is untested and may need a second try to get it right.
2011-04-14fix O_SYNC definition, cleanup fcntl.hRich Felker-11/+5
2011-04-14fcntl.h: move macros that do not vary between archs out of bitsRich Felker-24/+0
2011-04-14fix typo in legacy FAPPEND definitionRich Felker-1/+1
2011-04-13numerous fixes to sysv ipcRich Felker-24/+21
some of these definitions were just plain wrong, others based on outdated ancient "non-64" versions of the kernel interface. as much as possible has now been moved out of bits/* these changes break abi (the old abi for these functions was wrong), but since they were not working anyway it can hardly matter.
2011-04-11more types cleanupRich Felker-3/+0
the basic idea is that the only things in alltypes.h should be types that either vary from system to system (in practice, not just in theoretical la-la land - this is the implementation so we choose what constraints we want to impose on ports) or which are needed by multiple system headers.
2011-04-11cleanup types stuff in headers, fix missing u_int*_t in sys/types.hRich Felker-11/+0
2011-04-10add missing float.h macrosRich Felker-0/+3
actually FLT_ROUNDS needs to expand to a static inline function that obtains the current rounding mode and returns it, but that will be added later with fenv.h stuff.
2011-04-05add some missing ipv6 stuffRich Felker-0/+12
2011-04-05uncomment IP_PKTINFORich Felker-1/+1
this was a hack leftover from testing before the initial check-in to git.
2011-04-01remove obsolete and useless useconds_t typeRich Felker-1/+0
2011-03-30avoid all malloc/free in timer creation/destructionRich Felker-1/+1
instead of allocating a userspace structure for signal-based timers, simply use the kernel timer id. we use the fact that thread pointers will always be zero in the low bit (actually more) to encode integer timerid values as pointers. also, this change ensures that the timer_destroy syscall has completed before the library timer_destroy function returns, in case it matters.
2011-03-29some preliminaries for adding POSIX timersRich Felker-1/+1
2011-03-28fix bug from syscall overhaul: extra __syscall_ret call for 0-arg syscallsRich Felker-1/+1
this mainly just caused bloat, but could corrupt errno if a 0-arg syscall ever failed.
2011-03-25match glibc/lsb cancellation abi on i386Rich Felker-0/+19
glibc made the ridiculous choice to use pass-by-register calling convention for these functions, which is impossible to duplicate directly on non-gcc compilers. instead, we use ugly asm to wrap and convert the calling convention. presumably this works with every compiler anyone could potentially want to use.
2011-03-24overhaul cancellation to fix resource leaks and dangerous behavior with signalsRich Felker-0/+3
this commit addresses two issues: 1. a race condition, whereby a cancellation request occurring after a syscall returned from kernelspace but before the subsequent CANCELPT_END would cause cancellable resource-allocating syscalls (like open) to leak resources. 2. signal handlers invoked while the thread was blocked at a cancellation point behaved as if asynchronous cancellation mode wer in effect, resulting in potentially dangerous state corruption if a cancellation request occurs. the glibc/nptl implementation of threads shares both of these issues. with this commit, both are fixed. however, cancellation points encountered in a signal handler will not be acted upon if the signal was received while the thread was already at a cancellation point. they will of course be acted upon after the signal handler returns, so in real-world usage where signal handlers quickly return, it should not be a problem. it's possible to solve this problem too by having sigaction() wrap all signal handlers with a function that uses a pthread_cleanup handler to catch cancellation, patch up the saved context, and return into the cancellable function that will catch and act upon the cancellation. however that would be a lot of complexity for minimal if any benefit...
2011-03-19honor namespace for i386 syscall.h, even though it's not a standard headerRich Felker-50/+50
2011-03-19syscall overhaul part two - unify public and internal syscall interfaceRich Felker-169/+136
with this patch, the syscallN() functions are no longer needed; a variadic syscall() macro allows syscalls with anywhere from 0 to 6 arguments to be made with a single macro name. also, manually casting each non-integer argument with (long) is no longer necessary; the casts are hidden in the macros. some source files which depended on being able to define the old macro SYSCALL_RETURNS_ERRNO have been modified to directly use __syscall() instead of syscall(). references to SYSCALL_SIGSET_SIZE and SYSCALL_LL have also been changed. x86_64 has not been tested, and may need a follow-up commit to fix any minor bugs/oversights.
2011-03-19overhaul syscall interfaceRich Felker-423/+859
this commit shuffles around the location of syscall definitions so that we can make a syscall() library function with both SYS_* and __NR_* style syscall names available to user applications, provides the syscall() library function, and optimizes the code that performs the actual inline syscalls in the library itself. previously on i386 when built as PIC (shared library), syscalls were incurring bus lock (lock prefix) overhead at entry and exit, due to the way the ebx register was being loaded (xchg instruction with a memory operand). now the xchg takes place between two registers. further cleanup to arch/$(ARCH)/syscall.h is planned.
2011-03-18various legacy and linux-specific stuffRich Felker-0/+1
this commit is part of an effort to make more of busybox work out-of-the-box.