PAGESIZE is actually the version defined in POSIX base, with PAGE_SIZE
being in the XSI option. use PAGESIZE as the underlying definition to
facilitate making exposure of PAGE_SIZE conditional.
use of MB_CUR_MAX encoded a hidden dependency on the currently active
locale for the calling thread, whereas nl_langinfo_l is supposed to
report for the locale passed as an argument.
general policy is that all source files defining a public API or an
ABI mechanism referenced by a public header should include the public
header that declares the interface, so that the compiler or analysis
tools can check the consistency of the declarations. Alexander Monakov
pointed out a number of violations of this principle a few years back.
fix them now.
add a member of appropriate type to the fpos_t union so that accesses
are well-defined. use long long instead of off_t since off_t is not
always exposed in stdio.h and there's no namespace-clean alias for it.
access is still performed using pointer casts rather than by naming
the union member as a matter of style; to the extent possible, the
naming of fields in opaque types defined in the public headers is not
treated as an API contract with the implementation. access via the
pointer cast is valid as long as the union has a member of matching
type.
previously this macro used an odd if/else form instead of the more
idiomatic do/while(0), making it unsafe against omission of trailing
semicolon. the omission would make the following statement conditional
instead of producing an error.
formally, calling readv with a zero-length first iov component should
behave identically to calling read on just the second component, but
presence of a zero-length iov component has triggered bugs in some
kernels and performs significantly worse than a simple read on some
file types.
the stdio FILE read backend's return type is size_t, not ssize_t, and
all of the special (non-fd-backed) FILE types already return the
number of bytes read (zero) on error or eof. only __stdio_read leaked
a syscall error return into its return value.
fread had a workaround for this behavior going all the way back to the
original check-in. remove the workaround since it's no longer needed.
the ':' in optstring has special meaning as a flag applying to the
previous option character, or to getopt's error handling behavior when
it appears at the beginning. don't also accept a "-:" option based on
its presence.
based loosely on patch by Hauke Mehrtens; converted to wrap the public
API of the underlying getrandom function rather than direct syscalls,
so that if/when a fallback implementation of getrandom is added it
will automatically get picked up by getentropy too.
NT_ARM_SVE and NT_S390_RI_CB are new in linux commits
43d4da2c45b2f5d62f8a79ff7c6f95089bb24656 and
262832bc5acda76fd8f901d39f4da1121d951222
the rest are older.
musl missed NT_PRFPREG because it followed the glibc api:
https://sourceware.org/bugzilla/show_bug.cgi?id=14890
PR_SVE_SET_VL and PR_SVE_GET_VL controls are new in linux commit
2d2123bc7c7f843aa9db87720de159a049839862
related PR_SVE_* macros were added in
7582e22038a266444eb87bc07c372592ad647439
HWCAP_SVE is new in linux commit 43994d824e8443263dc98b151e6326bf677be52e
HWCAP_SHA3, HWCAP_SM3, HWCAP_SM4, HWCAP_ASIMDDP and HWCAP_SHA512 are new in
f5e035f8694c3bdddc66ea46ecda965ee6853718
PPC_FEATURE2_HTM_NO_SUSPEND is new in linux commit
cba6ac4869e45cc93ac5497024d1d49576e82666
PPC_FEATURE2_DARN and PPC_FEATURE2_SCV were new in v4.12 in commit
a4700a26107241cc7b9ac8528b2c6714ff99983d
for synchronous page faults, new in linux commit
1c9725974074a047f6080eecc62c50a8e840d050 and
b6fb293f2497a9841d94f6b57bd2bb2cd222da43
note that only targets that use asm-generic/mman.h have this new
flag defined, so undef it on other targets (mips*, powerpc*).
use the same token to define TIOCSER_TEMT as is used in ioctl.h
so when both headers are included there are no redefinition warnings
during musl build.
*_HUGE_SHIFT, *_HUGE_2MB, *_HUGE_1GB are documented in the man page,
so add all of the *_HUGE_* macros from linux uapi.
if MAP_HUGETLB is set, top bits of the mmap flags encode the page size.
see the linux commit aafd4562dfee81a40ba21b5ea3cf5e06664bc7f6
if SHM_HUGETLB is set, top bits of the shmget flags encode the page size.
see the linux commit 4da243ac1cf6aeb30b7c555d56208982d66d6d33
*_HUGE_16GB is defined unsigned to avoid signed left shift ub.
new ethertypes in linux v4.14:
ETH_P_ERSPAN new in 84e54fe0a5eaed696dee4019c396f8396f5a908b
ETH_P_IFE new in 2804fd3af6ba5ae5737705b27146455eabe2e2f8
ETH_P_NSH new in 155e6f649757c902901e599c268f8b575ddac1f8
ETH_P_MAP new in 7373ae7e8f0bf2c0718422481da986db5058b005
MSG_ZEROCOPY socket send flag avoids copy in the kernel
new in linux commit 52267790ef52d7513879238ca9fac22c1733e0e3
SO_ZEROCOPY socket option enables MSG_ZEROCOPY if availale
new in linux commit 76851d1212c11365362525e1e2c0a18c97478e6b
add AF_SMC and PF_SMC for the IBM shared memory communication protocol.
new in linux commit ac7138746e14137a451f8539614cdd349153e0c0
(linux socket.h is not in uapi so this update was missed earlier)
these additions were made by scanning git log since the last major
update in commit 790580b2fc. in addition
to git-level commit authorship, "patch by" text in the commit message
was also scanned. this idiom was used in the past for patches that
underwent substantial edits when merging or where the author did not
provide a commit message. going forward, my intent is to use commit
authorship consistently for attribution.
as before my aim was adding everyone with either substantial code
contributions or a pattern of ongoing simple patch submission; any
omissions are unintentional.
Maintainer's note: at one point, -lcompiler_rt apparently worked, and
may still work and be preferable if one has manually installed the
library in a public lib directory. but with current versions of clang,
the full pathname to the library file is needed. the original patch
removed the -lcompiler_rt check; I have left it in place in case there
are users depending on it, and since, when it does work, it's
preferable so as not to code a dependency on the specific compiler
version and paths in config.mak.
this is more extensible if we need to consider additional errors, and
more efficient as long as the compiler does not know it can cache the
result of __errno_location (a surprisingly complex issue detailed in
commit a603a75a72).
It's better to make execvp continue PATH search on ENOTDIR rather than
issuing an error. Bogus entries should not render rest of PATH invalid.
Maintainer's note: POSIX seems to require the search to continue like
this as part of XBD 8.3 Other Environment Variables. Only errors that
conclusively determine non-existence are candidates for continuing;
otherwise for consistency we have to report the error.
when a null buffer pointer is passed to fmemopen, requesting it
allocate its own memory buffer, extremely large size arguments near
SIZE_MAX could overflow and result in underallocation. this results
from omission of the size of the cookie structure in the overflow
check but inclusion of it in the calloc call.
instead of accounting for individual small contributions to the total
allocation size needed, simply reject sizes larger than PTRDIFF_MAX,
which will necessarily fail anyway. then adding arbitrary fixed-size
structures is safe without matching up the expressions in the
comparison and the allocation.
Currently getcwd(3) can succeed without returning an absolute path
because the underlying getcwd syscall, starting with linux commit
v2.6.36-rc1~96^2~2, may succeed without returning an absolute path.
This is a conformance issue because "The getcwd() function shall
place an absolute pathname of the current working directory
in the array pointed to by buf, and return buf".
Fix this by checking the path returned by syscall and failing with
ENOENT if the path is not absolute. The error code is chosen for
consistency with the case when the current directory is unlinked.
Similar issue was fixed in glibc recently, see
https://sourceware.org/bugzilla/show_bug.cgi?id=22679
in theory non-absolute origins can only arise when either the main
program is invoked by running ldso as a command (inherently non-suid)
or when dlopen was called with a relative pathname containing at least
one slash. such usage would be inherently insecure in an suid program
anyway, so the old behavior here does not seem to have been insecure.
harden against it anyway.
Rich Felker
Hauke Mehrtens
Szabolcs Nagy
Matúš Olekšák
Przemyslaw Pawelczyk
Dmitry V. Levin