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* manual: Fix ld.so diagnostics menu/section structureFlorian Weimer2023-09-061-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | And shorten the section/node names a bit, so that the menu entries become easier to read. Texinfo 6.5 fails to process the previous structure: ./dynlink.texi:56: warning: node `Dynamic Linker Introspection' is next for `Dynamic Linker Diagnostics' in sectioning but not in menu ./dynlink.texi:56: warning: node up `Dynamic Linker Diagnostics' in menu `Dynamic Linker Invocation' and in sectioning `Dynamic Linker' differ ./dynlink.texi:1: node `Dynamic Linker' lacks menu item for `Dynamic Linker Diagnostics' despite being its Up target ./dynlink.texi:226: warning: node prev `Dynamic Linker Introspection' in menu `Dynamic Linker Invocation' and in sectioning `Dynamic Linker Diagnostics' differ Texinfo 7.0.2 does not report an error. This fixes commit f21962ddfc8bb23e92597da1f98e313dbde11cc1 ("manual: Document ld.so --list-diagnostics output"). Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* linux: Add pidfd_getpidAdhemerval Zanella Netto2023-09-051-0/+38
| | | | | | | | | | | | | | | | | | | | | | | | This interface allows to obtain the associated process ID from the process file descriptor. It is done by parsing the procps fdinfo information. Its prototype is: pid_t pidfd_getpid (int fd) It returns the associated pid or -1 in case of an error and sets the errno accordingly. The possible errno values are those from open, read, and close (used on procps parsing), along with: - EBADF if the FD is negative, does not have a PID associated, or if the fdinfo fields contain a value larger than pid_t. - EREMOTE if the PID is in a separate namespace. - ESRCH if the process is already terminated. Checked on x86_64-linux-gnu on Linux 4.15 (no CLONE_PIDFD or waitid support), Linux 5.4 (full support), and Linux 6.2. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* posix: Add pidfd_spawn and pidfd_spawnp (BZ 30349)Adhemerval Zanella Netto2023-09-051-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Returning a pidfd allows a process to keep a race-free handle for a child process, otherwise, the caller will need to either use pidfd_open (which still might be subject to TOCTOU) or keep the old racy interface base on pid_t. To correct use pifd_spawn, the kernel must support not only returning the pidfd with clone/clone3 but also waitid (P_PIDFD) (added on Linux 5.4). If kernel does not support the waitid, pidfd return ENOSYS. It avoids the need to racy workarounds, such as reading the procfs fdinfo to get the pid to use along with other wait interfaces. These interfaces are similar to the posix_spawn and posix_spawnp, with the only difference being it returns a process file descriptor (int) instead of a process ID (pid_t). Their prototypes are: int pidfd_spawn (int *restrict pidfd, const char *restrict file, const posix_spawn_file_actions_t *restrict facts, const posix_spawnattr_t *restrict attrp, char *const argv[restrict], char *const envp[restrict]) int pidfd_spawnp (int *restrict pidfd, const char *restrict path, const posix_spawn_file_actions_t *restrict facts, const posix_spawnattr_t *restrict attrp, char *const argv[restrict_arr], char *const envp[restrict_arr]); A new symbol is used instead of a posix_spawn extension to avoid possible issues with language bindings that might track the return argument lifetime. Although on Linux pid_t and int are interchangeable, POSIX only states that pid_t should be a signed integer. Both symbols reuse the posix_spawn posix_spawn_file_actions_t and posix_spawnattr_t, to void rehash posix_spawn API or add a new one. It also means that both interfaces support the same attribute and file actions, and a new flag or file action on posix_spawn is also added automatically for pidfd_spawn. Also, using posix_spawn plumbing allows the reusing of most of the current testing with some changes: - waitid is used instead of waitpid since it is a more generic interface. - tst-posix_spawn-setsid.c is adapted to take into consideration that the caller can check for session id directly. The test now spawns itself and writes the session id as a file instead. - tst-spawn3.c need to know where pidfd_spawn is used so it keeps an extra file description unused. Checked on x86_64-linux-gnu on Linux 4.15 (no CLONE_PIDFD or waitid support), Linux 5.4 (full support), and Linux 6.2. Reviewed-by: Florian Weimer <fweimer@redhat.com>
* elf: Check that --list-diagnostics output has the expected syntaxFlorian Weimer2023-08-251-0/+8
| | | | | | | | | | Parts of elf/tst-rtld-list-diagnostics.py have been copied from scripts/tst-ld-trace.py. The abnf module is entirely optional and used to verify the ABNF grammar as included in the manual. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* manual: Document ld.so --list-diagnostics outputFlorian Weimer2023-08-251-0/+207
| | | | Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* manual/jobs.texi: Add missing @item EPERM for getpgidMark Wielaard2023-08-251-0/+1
| | | | | | | The missing @item makes it look like errno will be set to ESRCH if a cross-session getpgid is not permitted. Found by ulfvonbelow on irc.
* PowerPC: Influence cpu/arch hwcap features via GLIBC_TUNABLESMahesh Bodapati2023-08-011-1/+4
| | | | | | | | | | | This patch enables the option to influence hwcaps used by PowerPC. The environment variable, GLIBC_TUNABLES=glibc.cpu.hwcaps=-xxx,yyy,-zzz...., can be used to enable CPU/ARCH feature yyy, disable CPU/ARCH feature xxx and zzz, where the feature name is case-sensitive and has to match the ones mentioned in the file{sysdeps/powerpc/dl-procinfo.c}. Note that the hwcap tunables only used in the IFUNC selection. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* install.texi: Build was tested with binutils 2.41 (just released)Andreas K. Hüttel2023-07-301-1/+1
| | | | Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>
* install.texi: Update versions of most recent build toolsAndreas K. Hüttel2023-07-271-7/+7
| | | | Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>
* contrib.texi: Update for 2.38Andreas K. Hüttel2023-07-271-7/+103
| | | | Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>
* <sys/platform/x86.h>: Add APX supportH.J. Lu2023-07-271-0/+3
| | | | | | | | Add support for Intel Advanced Performance Extensions: https://www.intel.com/content/www/us/en/developer/articles/technical/advanced-performance-extensions-apx.html to <sys/platform/x86.h>.
* configure: Disable building libcrypt by defaultSiddhesh Poyarekar2023-07-201-10/+12
| | | | | | | | | | | | We mentioned eventual dropping of libcrypt in the 2.28 NEWS. Actually put that plan in motion by first disabling building libcrypt by default. note in NEWS that the library will be dropped completely in a future release. Also add a couple of builds into build-many-glibcs.py. Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> Reviewed-by: Andreas K. Hüttel <dilfridge@gentoo.org>
* configure: Use autoconf 2.71Siddhesh Poyarekar2023-07-171-1/+1
| | | | | | | | | | | | | | Bump autoconf requirement to 2.71 to allow regenerating configure on more recent distributions. autoconf 2.71 has been in Fedora since F36 and is the current version in Debian stable (bookworm). It appears to be current in Gentoo as well. All sysdeps configure and preconfigure scripts have also been regenerated; all changes are trivial transformations that do not affect functionality. Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org> Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* manual: Fix typos in struct dl_find_objectBert Wesarg2023-07-131-2/+2
| | | | | Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com> Reviewed-by: Florian Weimer <fweimer@redhat.com>
* Allow glibc to be built with _FORTIFY_SOURCEFrédéric Bérat2023-07-051-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Add --enable-fortify-source option. It is now possible to enable fortification through a configure option. The level may be given as parameter, if none is provided, the configure script will determine what is the highest level possible that can be set considering GCC built-ins availability and set it. If level is explicitly set to 3, configure checks if the compiler supports the built-in function necessary for it or raise an error if it isn't. If the configure option isn't explicitly enabled, it _FORTIFY_SOURCE is forcibly undefined (and therefore disabled). The result of the configure checks are new variables, ${fortify_source} and ${no_fortify_source} that can be used to appropriately populate CFLAGS. A dedicated patch will follow to make use of this variable in Makefiles when necessary. Updated NEWS and INSTALL. Adding dedicated x86_64 variant that enables the configuration. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* manual: Update documentation of strerror and related functionsFlorian Weimer2023-07-031-26/+98
| | | | | | | | | | | | The current implementation of strerror is thread-safe, but this has implications for the lifetime of the return string. Describe the strerror_l function. Describe both variants of the strerror_r function. Mention the lifetime of the returned string for strerrorname_np and strerrordesc_np. Clarify that perror output depends on the current locale. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* manual: Enhance documentation of the <ctype.h> functionsFlorian Weimer2023-07-031-8/+24
| | | | | | | | Describe the problems with signed characters, and the glibc extension to deal with most of them. Mention that the is* functions return zero for the special argument EOF. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Call "CST" a time zone abbreviation, not a namePaul Eggert2023-06-222-12/+12
| | | | | | In documentation, call strings like "CST" time zone abbreviations, not time zone names. This terminology is more precise, and is what tzdb uses. A string like "CST" is ambiguous and does not fully name a time zone.
* C2x scanf %b supportJoseph Myers2023-06-191-3/+9
| | | | | | | | | | | | ISO C2x defines scanf %b for input of binary integers (with an optional 0b or 0B prefix). Implement such support, along with the corresponding SCNb* macros in <inttypes.h>. Unlike the support for binary integers with 0b or 0B prefix with scanf %i, this is supported in all versions of scanf (independent of the standards mode used for compilation), because there are no backwards compatibility concerns (%b wasn't previously a supported format) the way there were for %i. Tested for x86_64 and x86.
* C2x printf %wN, %wfN support (bug 24466)Joseph Myers2023-06-191-0/+18
| | | | | | | | | | | | | | | | | | ISO C2x defines printf length modifiers wN (for intN_t / int_leastN_t / uintN_t / uint_leastN_t) and wfN (for int_fastN_t / uint_fastN_t). Add support for those length modifiers (such a feature was previously requested in bug 24466). scanf support is to be added separately. GCC 13 has format checking support for these modifiers. When used with the support for registering format specifiers, these modifiers are translated to existing flags in struct printf_info, rather than trying to add some way of distinguishing them without breaking the printf_info ABI. C2x requires an error to be returned for unsupported values of N; this is implemented for printf-family functions, but the parse_printf_format interface doesn't support error returns, so such an error gets discarded by that function. Tested for x86_64 and x86.
* manual: Manual update for strlcat, strlcpy, wcslcat, wclscpyPaul Eggert2023-06-142-3/+101
| | | | | Co-authored-by: Florian Weimer <fweimer@redhat.com> Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* Fix misspellings in manual/ -- BZ 25337Paul Pluzhnikov2023-05-2713-15/+15
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* aligned_alloc: conform to C17DJ Delorie2023-05-081-1/+1
| | | | | | | This patch adds the strict checking for power-of-two alignments in aligned_alloc(), and updates the manual accordingly. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* manual: Remove unsupported line breaks in waiting-with-clock sectionFlorian Weimer2023-05-081-21/+8
| | | | | | | The argument to @deftypefun must be on a single line. Also add the missing @safety for sem_clockwait. Reported-by: Nilgün Belma Bugüner <nillguine@gmail.com>
* Revert "riscv: Resolve symbols directly for symbols with STO_RISCV_VARIANT_CC."Florian Weimer2023-05-071-6/+0
| | | | | | | This reverts commit 117e8b341c5c0ace8d65feeef136fececb3fdc9c. Reason for revert: Causes elf/tst-glibcelf and elf/tst-relro-* to fail on all architectures.
* Enable libmvec support for AArch64Joe Ramsay2023-05-031-0/+3
| | | | | | | | | | | | | | | | | | | | | | | This patch enables libmvec on AArch64. The proposed change is mainly implementing build infrastructure to add the new routines to ABI, tests and benchmarks. I have demonstrated how this all fits together by adding implementations for vector cos, in both single and double precision, targeting both Advanced SIMD and SVE. The implementations of the routines themselves are just loops over the scalar routine from libm for now, as we are more concerned with getting the plumbing right at this point. We plan to contribute vector routines from the Arm Optimized Routines repo that are compliant with requirements described in the libmvec wiki. Building libmvec requires minimum GCC 10 for SVE ACLE. To avoid raising the minimum GCC by such a big jump, we allow users to disable libmvec if their compiler is too old. Note that at this point users have to manually call the vector math functions. This seems to be acceptable to some downstream users. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* riscv: Resolve symbols directly for symbols with STO_RISCV_VARIANT_CC.Hsiangkai Wang2023-04-281-0/+6
| | | | | | | | | | | | | | | | | | | | | In some cases, we do not want to go through the resolver for function calls. For example, functions with vector arguments will use vector registers to pass arguments. In the resolver, we do not save/restore the vector argument registers for lazy binding efficiency. To avoid ruining the vector arguments, functions with vector arguments will not go through the resolver. To achieve the goal, we will annotate the function symbols with STO_RISCV_VARIANT_CC flag and add DT_RISCV_VARIANT_CC tag in the dynamic section. In the first pass on PLT relocations, we do not set up to call _dl_runtime_resolve. Instead, we resolve the functions directly. Signed-off-by: Hsiangkai Wang <kai.wang@sifive.com> Signed-off-by: Vincent Chen <vincent.chen@sifive.com> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> Acked-by: Palmer Dabbelt <palmer@rivosinc.com> Link: https://inbox.sourceware.org/libc-alpha/20230314162512.35802-1-kito.cheng@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
* manual: document posix_openpt (bug 17010)Gavin Smith2023-04-261-3/+33
| | | | | | | | State that getpt is similar to posix_openpt. Use posix_openpt instead of getpt in example. Signed-off-by: Gavin Smith <gavinsmith0123@gmail.com> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Created tunable to force small pages on stack allocation.Cupertino Miranda2023-04-201-0/+15
| | | | | | | | | | Created tunable glibc.pthread.stack_hugetlb to control when hugepages can be used for stack allocation. In case THP are enabled and glibc.pthread.stack_hugetlb is set to 0, glibc will madvise the kernel not to use allow hugepages for stack allocations. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* manual: update AddressSanitizer discussionPaul Eggert2023-04-081-5/+4
| | | | | | | * manual/string.texi (Truncating Strings): Update obsolescent reference and use the more-generic term “AddressSanitizer”. Mention fortification, too. -fcheck-pointer-bounds is no longer supported.
* manual: document snprintf truncation betterPaul Eggert2023-04-081-1/+4
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* manual: improve string section wordingPaul Eggert2023-04-081-13/+21
| | | | | | | | | | * manual/string.texi: Editorial fixes. Do not say “text” when “string” or “string contents” is meant, as a C string can contain bytes that are not valid text in the current encoding. When warning about strcat efficiency, warn similarly about strncat and wcscat. “coping” → “copying”. Mention at the start of the two problematic sections that problems are discussed at section end.
* manual: fix texinfo typoPaul Eggert2023-04-081-2/+1
| | | | | * manual/creature.texi (Feature Test Macros): Fix “creature.texi:309: warning: `.' or `,' must follow @xref, not f”.
* <sys/platform/x86.h>: Add PREFETCHI supportH.J. Lu2023-04-051-0/+3
| | | | | Add PREFETCHI support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add AMX-COMPLEX supportH.J. Lu2023-04-051-0/+3
| | | | | Add AMX-COMPLEX support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add AVX-NE-CONVERT supportH.J. Lu2023-04-051-0/+3
| | | | | Add AVX-NE-CONVERT support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add AVX-VNNI-INT8 supportH.J. Lu2023-04-051-0/+3
| | | | | Add AVX-VNNI-INT8 support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add MSRLIST supportH.J. Lu2023-04-051-0/+4
| | | | | Add MSRLIST support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add AVX-IFMA supportH.J. Lu2023-04-051-0/+3
| | | | | Add AVX-IFMA support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add AMX-FP16 supportH.J. Lu2023-04-051-0/+3
| | | | | Add AMX-FP16 support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add WRMSRNS supportH.J. Lu2023-04-051-0/+3
| | | | | Add WRMSRNS support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add ArchPerfmonExt supportH.J. Lu2023-04-051-0/+4
| | | | | | Add Architectural Performance Monitoring Extended Leaf (EAX = 23H) support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add CMPCCXADD supportH.J. Lu2023-04-051-0/+3
| | | | | Add CMPCCXADD support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add LASS supportH.J. Lu2023-04-051-0/+3
| | | | | Add Linear Address Space Separation (LASS) support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add RAO-INT supportH.J. Lu2023-04-051-0/+3
| | | | | Add RAO-INT support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add LBR supportH.J. Lu2023-04-051-0/+3
| | | | | Add architectural LBR support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add RTM_FORCE_ABORT supportH.J. Lu2023-04-051-0/+3
| | | | | Add RTM_FORCE_ABORT support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add SGX-KEYS supportH.J. Lu2023-04-051-0/+3
| | | | | Add SGX-KEYS support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add BUS_LOCK_DETECT supportH.J. Lu2023-04-051-0/+3
| | | | | | Add Bus lock debug exceptions (BUS_LOCK_DETECT) support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
* <sys/platform/x86.h>: Add LA57 supportH.J. Lu2023-04-051-0/+3
| | | | | | Add 57-bit linear addresses and five-level paging (LA57) support to <sys/platform/x86.h>. Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>