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2013-07-24add _l versions of strtod family functions, purely as aliasesRich Felker-0/+8
this is a cheat since the _l versions take an extra argument, but since these functions are only here for ABI purposes, it doesn't really matter as long as the ABI matches. if the non-__-prefixed versions are eventually made public, they should proabably be real functions rather than hacks like this.
2013-07-24add __wcsftime_l symbolRich Felker-3/+9
unlike the strftime commit, this one is purely an ABI compatibility issue. the previous version of the code would have worked just as well with LC_TIME once LC_TIME support is added.
2013-07-24move strftime_l into strftime.c and add __-prefixed versionRich Felker-8/+10
the latter is both for ABI purposes, and to facilitate eventually adding LC_TIME support. it's also nice to eliminate an extra source file.
2013-07-24make getaddrinfo with AF_UNSPEC and null host return both IPv4 and v6Rich Felker-14/+23
based on a patch by orc, with indexing and flow control cleaned up a little bit. this code is all going to be replaced at some point in the near future.
2013-07-24support STB_GNU_UNIQUE symbol bindings in dynamic linkerRich Felker-1/+1
these are needed for some C++ library binaries including most builds of libstdc++. I'm not entirely clear on the rationale. this patch does not implement any special semantics for them, but as far as I can tell, no special treatment is needed in correctly-linked programs; this binding seems to exist only for catching incorrectly-linked programs.
2013-07-24move the dynamic linker's jmp_buf from static to automatic storageRich Felker-5/+7
this more than compensates for the size increase of jmp_buf, and greatly reduces bss/data size on archs with huge jmp_buf.
2013-07-24change jmp_buf to share an underlying type and struct tag with sigjmp_bufRich Felker-2/+2
this is necessary to meet the C++ ABI target. alternatives were considered to avoid the size increase for non-sig jmp_buf objects, but they seemed to have worse properties. moreover, the relative size increase is only extreme on x86[_64]; one way of interpreting this is that, if the size increase from this patch makes jmp_buf use too much memory, then the program was already using too much memory when built for non-x86 archs.
2013-07-23remove redundant check in memalignRich Felker-1/+1
the case where mem was already aligned is handled earlier in the function now.
2013-07-23fix heap corruption bug in memalignRich Felker-1/+3
this bug was caught by the new footer-corruption check in realloc and free. if the block returned by malloc was already aligned to the desired alignment, memalign's logic to split off the misaligned head was incorrect; rather than writing to a point inside the allocated block, it was overwriting the footer of the previous block on the heap with the value 1 (length 0 plus an in-use flag). fortunately, the impact of this bug was fairly low. (this is probably why it was not caught sooner.) due to the way the heap works, malloc will never return a block whose previous block is free. (doing so would be harmful because it would increase fragmentation with no benefit.) the footer is actually not needed for in-use blocks, except that its in-use bit needs to remain set so that it does not get merged with free blocks, so there was no harm in it being set to 1 instead of the correct value. however, there is one case where this bug could have had an impact: in multi-threaded programs, if another thread freed the previous block after memalign's call to malloc returned, but before memalign overwrote the previous block's footer, the resulting block in the free list could be left in a corrupt state. I have not analyzed the impact of this bad state and whether it could lead to more serious malfunction.
2013-07-22disable legacy init/fini processing on ARMRich Felker-0/+4
since the old, poorly-thought-out musl approach to init/fini arrays on ARM (when it was the only arch that needed them) was to put the code in crti/crtn and have the legacy _init/_fini code run the arrays, adding proper init/fini array support caused the arrays to get processed twice on ARM. I'm not sure skipping legacy init/fini processing is the best solution to the problem, but it works, and it shouldn't break anything since the legacy init/fini system was never used for ARM EABI.
2013-07-22make pthread attribute types structs, even when they just have one fieldRich Felker-22/+22
this change is to get the right tags for C++ ABI matching. it should have no other effects.
2013-07-22refactor headers, especially alltypes.h, and improve C++ ABI compatRich Felker-3/+3
the arch-specific bits/alltypes.h.sh has been replaced with a generic alltypes.h.in and minimal arch-specific bits/alltypes.h.in. this commit is intended to have no functional changes except: - exposing additional symbols that POSIX allows but does not require - changing the C++ name mangling for some types - fixing the signedness of blksize_t on powerpc (POSIX requires signed) - fixing the limit macros for sig_atomic_t on x86_64 - making dev_t an unsigned type (ABI matching goal, and more logical) in addition, some types that were wrongly defined with long on 32-bit archs were changed to int, and vice versa; this change is non-functional except for the possibility of making pointer types mismatch, and only affects programs that were using them incorrectly, and only at build-time, not runtime. the following changes were made in the interest of moving non-arch-specific types out of the alltypes system and into the headers they're associated with, and also will tend to improve application compatibility: - netdb.h now includes netinet/in.h (for socklen_t and uint32_t) - netinet/in.h now includes sys/socket.h and inttypes.h - sys/resource.h now includes sys/time.h (for struct timeval) - sys/wait.h now includes signal.h (for siginfo_t) - langinfo.h now includes nl_types.h (for nl_item) for the types in stdint.h: - types which are of no interest to other headers were moved out of the alltypes system. - fast types for 8- and 64-bit are hard-coded (at least for now); only the 16- and 32-bit ones have reason to vary by arch. and the following types have been changed for C++ ABI purposes; - mbstate_t now has a struct tag, __mbstate_t - FILE's struct tag has been changed to _IO_FILE - DIR's struct tag has been changed to __dirstream - locale_t's struct tag has been changed to __locale_struct - pthread_t is defined as unsigned long in C++ mode only - fpos_t now has a struct tag, _G_fpos64_t - fsid_t's struct tag has been changed to __fsid_t - idtype_t has been made an enum type (also required by POSIX) - nl_catd has been changed from long to void * - siginfo_t's struct tag has been removed - sigset_t's has been given a struct tag, __sigset_t - stack_t has been given a struct tag, sigaltstack - suseconds_t has been changed to long on 32-bit archs - [u]intptr_t have been changed from long to int rank on 32-bit archs - dev_t has been made unsigned summary of tests that have been performed against these changes: - nsz's libc-test (diff -u before and after) - C++ ABI check symbol dump (diff -u before, after, glibc) - grepped for __NEED, made sure types needed are still in alltypes - built gcc 3.4.6
2013-07-21remove __libc_csu_* cruftRich Felker-10/+0
these functions were mistakenly assumed to be needed to match glibc ABI, but glibc has them as part of the non-shared part of libc that's always statically linked into the main program. moreover, the only place they are referenced from is glibc's crt1.o.
2013-07-21add support for init/fini array in main program, and greatly simplifyRich Felker-26/+33
modern (4.7.x and later) gcc uses init/fini arrays, rather than the legacy _init/_fini function pasting and crtbegin/crtend ctors/dtors system, on most or all archs. some archs had already switched a long time ago. without following this change, global ctors/dtors will cease to work under musl when building with new gcc versions. the most surprising part of this patch is that it actually reduces the size of the init code, for both static and shared libc. this is achieved by (1) unifying the handling main program and shared libraries in the dynamic linker, and (2) eliminating the glibc-inspired rube goldberg machine for passing around init and fini function pointers. to clarify, some background: the function signature for __libc_start_main was based on glibc, as part of the original goal of being able to run some glibc-linked binaries. it worked by having the crt1 code, which is linked into every application, static or dynamic, obtain and pass pointers to the init and fini functions, which __libc_start_main is then responsible for using and recording for later use, as necessary. however, in neither the static-linked nor dynamic-linked case do we actually need crt1.o's help. with dynamic linking, all the pointers are available in the _DYNAMIC block. with static linking, it's safe to simply access the _init/_fini and __init_array_start, etc. symbols directly. obviously changing the __libc_start_main function signature in an incompatible way would break both old musl-linked programs and glibc-linked programs, so let's not do that. instead, the function can just ignore the information it doesn't need. new archs need not even provide the useless args in their versions of crt1.o. existing archs should continue to provide it as long as there is an interest in having newly-linked applications be able to run on old versions of musl; at some point in the future, this support can be removed.
2013-07-21fix order of fini_array execution for shared libsRich Felker-2/+2
2013-07-20add support for init_array/fini_array ctors/dtors to dynamic linkerRich Felker-2/+13
2013-07-20fix shm_open wrongly being cancellableRich Felker-1/+6
2013-07-20fix uninitialized/stale use of alloc (%m modifier) flag in scanfRich Felker-0/+4
for conversion specifiers, alloc is always set when the specifier is parsed. however, if scanf stops due to mismatching literal text, either an uninitialized (if no conversions have been performed yet) or stale (from the previous conversion) of the flag will be used, possibly causing an invalid pointer to be passed to free when the function returns.
2013-07-19harden realloc/free to detect simple overflowsRich Felker-0/+6
the sizes in the header and footer for a chunk should always match. if they don't, the program has definitely invoked undefined behavior, and the most likely cause is a simple overflow, either of a buffer in the block being freed or the one just below it. crashing here should not only improve security of buggy programs, but also aid in debugging, since the crash happens in a context where you have a pointer to the likely-overflowed buffer.
2013-07-19improve [f]stat[v]fs functions, and possibly work around old kernelsRich Felker-2/+5
the main aim of this patch is to ensure that if not all fields are filled in, they contain zeros, so as not to confuse applications. reportedly some older kernels, including commonly used openvz kernels, lack the f_flags field, resulting in applications reading random junk as the mount flags; the common symptom seems to be wrongly considering the filesystem to be mounted read-only and refusing to operate. glibc has some amazingly ugly fallback code to get the mount flags for old kernels, but having them really is not that important anyway; what matters most is not presenting incorrect flags to the application. I have also aimed to fill in some fields of statvfs that were previously missing, and added code to explicitly zero the reserved space at the end of the structure, which will make things easier in the future if this space someday needs to be used.
2013-07-19change uid_t, gid_t, and id_t to unsigned typesRich Felker-6/+20
this change is both to fix one of the remaining type (and thus C++ ABI) mismatches with glibc/LSB and to allow use of the full range of uid and gid values, if so desired. passwd/group access functions were not prepared to deal with unsigned values, so they too have been fixed with this commit.
2013-07-18make the dynamic linker find its path file relative to its own locationRich Felker-1/+20
prior to this change, using a non-default syslibdir was impractical on systems where the ordinary library paths contain musl-incompatible library files. the file containing search paths was always taken from /etc, which would either correspond to a system-wide musl installation, or fail to exist at all, resulting in searching of the default library path. the new search strategy is safe even for suid programs because the pathname used comes from the PT_INTERP header of the program being run, rather than any external input. as part of this change, I have also begun differentiating the names of arch variants that differ by endianness or floating point calling convention. the corresponding changes in the build system and and gcc wrapper script (to use an alternate dynamic linker name) for these configurations have not yet been made.
2013-07-18fix off-by-one error in checks for implementation-internal signal numbersRich Felker-3/+3
2013-07-17make posix_spawn (and functions that use it) use CLONE_VFORK flagRich Felker-1/+2
this is both a minor scheduling optimization and a workaround for a difficult-to-fix bug in qemu app-level emulation. from the scheduling standpoint, it makes no sense to schedule the parent thread again until the child has exec'd or exited, since the parent will immediately block again waiting for it. on the qemu side, as regular application code running on an underlying libc, qemu cannot make arbitrary clone syscalls itself without confusing the underlying implementation. instead, it breaks them down into either fork-like or pthread_create-like cases. it was treating the code in posix_spawn as pthread_create-like, due to CLONE_VM, which caused horribly wrong behavior: CLONE_FILES broke the synchronization mechanism, CLONE_SIGHAND broke the parent's signals, and CLONE_THREAD caused the child's exec to end the parent -- if it hadn't already crashed. however, qemu special-cases CLONE_VFORK and emulates that with fork, even when CLONE_VM is also specified. this also gives incorrect semantics for code that really needs the memory sharing, but posix_spawn does not make use of the vm sharing except to avoid momentary double commit charge. programs using posix_spawn (including via popen) should now work correctly under qemu app-level emulation.
2013-07-17fix missing argument in variadic syscall macrosRich Felker-1/+1
for 0-argument syscalls (1 argument to the macro, the syscall number), the __SYSCALL_NARGS_X macro's ... argument was not satisfied. newer compilers seem to care about this.
2013-07-17fix error code on time conversion overflowsRich Felker-4/+4
POSIX mandates EOVERFLOW for this condition.
2013-07-17fix fd leak in file mapping code used in new zoneinfo supportRich Felker-1/+1
2013-07-17the big time handling overhaulRich Felker-348/+649
this commit has two major user-visible parts: zoneinfo-format time zones are now supported, and overflow handling is intended to be complete in the sense that all functions return a correct result if and only if the result fits in the destination type, and otherwise return an error. also, some noticable bugs in the way DST detection and normalization worked have been fixed, and performance may be better than before, but it has not been tested.
2013-07-13fix omission of dtv setup in static linked programs on TLS variant I archsRich Felker-1/+1
apparently this was never noticed before because the linker normally optimizes dynamic TLS models to non-dynamic ones when static linking, thus eliminating the calls to __tls_get_addr which crash when the dtv is missing. however, some libsupc++ code on ARM was calling __tls_get_addr when static linked and crashing. the reason is unclear to me, but with this issue fixed it should work now anyway.
2013-07-10fix invalid library phdr pointers passed to callback from dl_iterate_phdrRich Felker-9/+16
map_library was saving pointers to an automatic-storage buffer rather than pointers into the mapping. this should be a fairly simple fix, but the patch here is slightly complicated by two issues: 1. supporting gratuitously obfuscated ELF files where the program headers are not right at the beginning of the file. 2. cleaning up the map_library function so that data isn't clobbered by the time we need it.
2013-07-09fix a couple misleading/wrong signal descriptions in strsignalRich Felker-2/+2
there are still several more that are misleading, but SIGFPE (integer division error misdescribed as floating point) and and SIGCHLD (possibly non-exit status change events described as exiting) were the worst offenders.
2013-07-09add realtime signals to strsignalRich Felker-3/+19
the name format RTnn/RTnnn was chosen to minimized bloat while uniquely identifying the signal.
2013-07-09fix off-by-one array bound in strsignalRich Felker-1/+1
2013-07-09fix bogus lazy allocation in ctermid and missing malloc failure checkRich Felker-10/+7
also clean up, optimize, and simplify the code, removing branches by simply pre-setting the result string to an empty string, which will be preserved if other operations fail.
2013-07-09fix fd leak on races and cancellation in ctermidRich Felker-2/+3
2013-07-09fix missing SOCK_CLOEXEC in various functions that use sockets internallyRich Felker-4/+4
2013-07-04move core memalign code from aligned_alloc to __memalignRich Felker-49/+55
there are two motivations for this change. one is to avoid gratuitously depending on a C11 symbol for implementing a POSIX function. the other pertains to the documented semantics. C11 does not define any behavior for aligned_alloc when the length argument is not a multiple of the alignment argument. posix_memalign on the other hand places no requirements on the length argument. using __memalign as the implementation of both, rather than trying to implement one in terms of the other when their documented contracts differ, eliminates this confusion.
2013-07-04move alignment check from aligned_alloc to posix_memalignRich Felker-1/+2
C11 has no requirement that the alignment be a multiple of sizeof(void*), and in fact seems to require any "valid alignment supported by the implementation" to work. since the alignment of char is 1 and thus a valid alignment, an alignment argument of 1 should be accepted.
2013-07-01add stubs for additional legacy ether.h functionsRich Felker-0/+15
these would not be expensive to actually implement, but reading /etc/ethers does not sound like a particularly useful feature, so for now I'm leaving them as stubs.
2013-06-29fix failure of mbsrtowcs to record stop position when dest is fullRich Felker-1/+4
2013-06-29implement minimal dlinfo functionRich Felker-0/+20
2013-06-29add some comments about the mips ksigaction structure weirdnessRich Felker-0/+3
2013-06-29fix missing synchronization in calls from dynamic linker to global ctorsRich Felker-0/+4
this change is needed to correctly handle the case where a constructor creates a new thread which calls dlopen. previously, the lock was not held in this case. the reason for the complex logic to avoid locking whenever possible is that, since the mutex is recursive, it will need to inspect the thread pointer to get the current thread's tid, and this requires initializing the thread pointer. we do not want non-multi-threaded programs to attempt to access the thread pointer unnecessarily; doing so could make them crash on ancient kernels that don't support threads but which may otherwise be capable of running the program.
2013-06-29prevent shmget from allocating objects that overflow ptrdiff_tRich Felker-0/+2
rather than returning an error, we have to increase the size argument so high that the kernel will have no choice but to fail. this is because POSIX only permits the EINVAL error for size errors when a new shared memory segment would be created; if it already exists, the size argument must be ignored. unfortunately Linux is non-conforming in this regard, but I want to keep the code correct in userspace anyway so that if/when Linux is fixed, the behavior applications see will be conforming.
2013-06-28work around wrong kernel type for sem_nsems member of struct semid_dsRich Felker-0/+7
rejecting invalid values for n is fine even in the case where a new sem will not be created, since the kernel does its range checks on n even in this case as well. by default, the kernel will bound the limit well below USHRT_MAX anyway, but it's presumably possible that an administrator could override this limit and break things.
2013-06-28implement week-based-year year numbers in strftimeRich Felker-27/+34
in the process, I refactored the week-number code so it can be used by the week-based-year formats to determine year adjustments at the boundary values. this also improves indention/code readability.
2013-06-28fix breakage in last commit to strftime due to missing INT_MAXRich Felker-0/+1
that's what I get for changing a hard-coded threshold to a proper non-magic-number without testing.
2013-06-28implement week numbers and half of the week-based-year logic for strftimeRich Felker-3/+38
output for plain week numbers (%U and %W) has been sanity-checked, and output for the week-based-year week numbers (%V) has been checked extensively against known-good data for the full non-negative range of 32-bit time_t. year numbers for week-based years (%g and %G) are not yet implemented.
2013-06-27disallow creation of objects larger than PTRDIFF_MAX via mmapRich Felker-0/+5
internally, other parts of the library assume sizes don't overflow ssize_t and/or ptrdiff_t, and the way this assumption is made valid is by preventing creating of such large objects. malloc already does so, but the check was missing from mmap. this is also a quality of implementation issue: even if the implementation internally could handle such objects, applications could inadvertently invoke undefined behavior by subtracting pointers within an object. it is very difficult to guard against this in applications, so a good implementation should simply ensure that it does not happen.
2013-06-26fix syscall argument bug in pthread_getschedparamRich Felker-1/+1
the address of the pointer to the sched param, rather than the pointer, was being passed to the kernel.