This patch adds pthread_getname_np and pthread_setname_np. These were added to glibc in 2.12[1] and are also present in some form on NetBSD and several UNIXes.
The code is based on NetBSD's implementation with changes to better match Linux behaviour. Implementation quirks: * pthread_setname_np with a NULL pointer segfaults (as linux) * pthread_setname_np accepts names longer than 16 characters (linux returns ERANGE) * pthread_getname_np with a NULL pointer returns EFAULT (as linux) * pthread_getname_np with a buffer length of less than 16 returns ERANGE (as linux) * pthread_getname_np truncates the thread name to fit the buffer length. This guarantees success even when the default thread name is longer than 16 characters, but means there is no way to discover the actual length of the thread name. (Linux always truncates the thread name to 16 characters) * Changing program_invocation_short_name changes the default thread name. I'll leave it up to you to decide any of these matter. This is implemented via class pthread_attr to make it easier to add pthread_attr_[gs]etname_np (present in NetBSD and some UNIXes) should it ever be added to Linux (or we decide we want it anyway). [1] https://sourceware.org/git/?p=glibc.git;a=blob;f=NEWS;h=d55a844d4ec06d164cb786c6c9f403a9672a674d;hb=e28c88707ef0529593fccedf1a94c3fce3df0ef3 Signed-off-by: Jon Turney <jon.tur...@dronecode.org.uk> --- winsup/cygwin/common.din | 2 ++ winsup/cygwin/include/cygwin/version.h | 3 +- winsup/cygwin/include/pthread.h | 2 ++ winsup/cygwin/release/2.6.0 | 4 +++ winsup/cygwin/thread.cc | 61 +++++++++++++++++++++++++++++++++- winsup/cygwin/thread.h | 1 + winsup/doc/new-features.xml | 12 +++++++ winsup/doc/posix.xml | 2 ++ 8 files changed, 85 insertions(+), 2 deletions(-) create mode 100644 winsup/cygwin/release/2.6.0 diff --git a/winsup/cygwin/common.din b/winsup/cygwin/common.din index d8df00e..1ebba2b 100644 --- a/winsup/cygwin/common.din +++ b/winsup/cygwin/common.din @@ -1014,6 +1014,7 @@ pthread_exit SIGFE pthread_getattr_np SIGFE pthread_getconcurrency SIGFE pthread_getcpuclockid SIGFE +pthread_getname_np SIGFE pthread_getschedparam SIGFE pthread_getsequence_np SIGFE pthread_getspecific SIGFE @@ -1054,6 +1055,7 @@ pthread_self SIGFE pthread_setcancelstate SIGFE pthread_setcanceltype SIGFE pthread_setconcurrency SIGFE +pthread_setname_np SIGFE pthread_setschedparam SIGFE pthread_setschedprio SIGFE pthread_setspecific SIGFE diff --git a/winsup/cygwin/include/cygwin/version.h b/winsup/cygwin/include/cygwin/version.h index 1f5bf72..d403f0e 100644 --- a/winsup/cygwin/include/cygwin/version.h +++ b/winsup/cygwin/include/cygwin/version.h @@ -454,12 +454,13 @@ details. */ nexttowardf, nexttowardl, pow10l, powl, remainderl, remquol, roundl, scalbl, scalblnl, scalbnl, sincosl, sinhl, sinl, tanhl, tanl, tgammal, truncl. + 298: Export pthread_getname_np, pthread_setname_np. Note that we forgot to bump the api for ualarm, strtoll, strtoull, sigaltstack, sethostname. */ #define CYGWIN_VERSION_API_MAJOR 0 -#define CYGWIN_VERSION_API_MINOR 297 +#define CYGWIN_VERSION_API_MINOR 298 /* There is also a compatibity version number associated with the shared memory regions. It is incremented when incompatible changes are made to the shared diff --git a/winsup/cygwin/include/pthread.h b/winsup/cygwin/include/pthread.h index 609eac2..47ee6bd 100644 --- a/winsup/cygwin/include/pthread.h +++ b/winsup/cygwin/include/pthread.h @@ -222,6 +222,8 @@ void pthread_testcancel (void); #if __GNU_VISIBLE int pthread_getattr_np (pthread_t, pthread_attr_t *); +int pthread_getname_np (pthread_t, char *, size_t) __attribute__((nonnull(2))); +int pthread_setname_np (pthread_t, const char *) __attribute__((nonnull(2))); int pthread_sigqueue (pthread_t *, int, const union sigval); int pthread_yield (void); #endif diff --git a/winsup/cygwin/release/2.6.0 b/winsup/cygwin/release/2.6.0 new file mode 100644 index 0000000..5f9f4db --- /dev/null +++ b/winsup/cygwin/release/2.6.0 @@ -0,0 +1,4 @@ +What's new: +----------- + +- New API: pthread_getname_np, pthread_setname_np, scandirat. diff --git a/winsup/cygwin/thread.cc b/winsup/cygwin/thread.cc index d9271fc..e41e0c1 100644 --- a/winsup/cygwin/thread.cc +++ b/winsup/cygwin/thread.cc @@ -1099,7 +1099,7 @@ pthread::resume () pthread_attr::pthread_attr ():verifyable_object (PTHREAD_ATTR_MAGIC), joinable (PTHREAD_CREATE_JOINABLE), contentionscope (PTHREAD_SCOPE_PROCESS), inheritsched (PTHREAD_INHERIT_SCHED), stackaddr (NULL), stacksize (0), -guardsize (wincap.def_guard_page_size ()) +guardsize (wincap.def_guard_page_size ()), name (NULL) { schedparam.sched_priority = 0; } @@ -2569,6 +2569,65 @@ pthread_getattr_np (pthread_t thread, pthread_attr_t *attr) return 0; } +#define NAMELEN 16 + +extern "C" int +pthread_getname_np (pthread_t thread, char *buf, size_t buflen) +{ + char *name; + + if (!pthread::is_good_object (&thread)) + return ESRCH; + + if (!thread->attr.name) + name = program_invocation_short_name; + else + name = thread->attr.name; + + // Return ERANGE if the provided buffer is less than NAMELEN. Truncate and + // zero-terminate the name to fit in buf. This means we always return + // something if the buffer is NAMELEN or larger, but there is no way to tell + // if we have the whole name. + if (buflen < NAMELEN) + return ERANGE; + + int ret = 0; + __try + { + strlcpy (buf, name, buflen); + } + __except (NO_ERROR) + { + ret = EFAULT; + } + __endtry + + return ret; +} + +#undef NAMELEN + +extern "C" int +pthread_setname_np (pthread_t thread, const char *name) +{ + char *oldname, *cp; + + if (!pthread::is_good_object (&thread)) + return ESRCH; + + cp = strdup(name); + if (!cp) + return ENOMEM; + + oldname = thread->attr.name; + thread->attr.name = cp; + + if (oldname) + free(oldname); + + return 0; +} + /* provided for source level compatability. See http://www.opengroup.org/onlinepubs/007908799/xsh/pthread_getconcurrency.html */ diff --git a/winsup/cygwin/thread.h b/winsup/cygwin/thread.h index 5d51913..48fb6fb 100644 --- a/winsup/cygwin/thread.h +++ b/winsup/cygwin/thread.h @@ -240,6 +240,7 @@ public: void *stackaddr; size_t stacksize; size_t guardsize; + char *name; pthread_attr (); ~pthread_attr (); diff --git a/winsup/doc/new-features.xml b/winsup/doc/new-features.xml index 9d428e2..c9b9bee 100644 --- a/winsup/doc/new-features.xml +++ b/winsup/doc/new-features.xml @@ -4,6 +4,18 @@ <sect1 id="ov-new"><title>What's new and what changed in Cygwin</title> +<sect2 id="ov-new2.6"><title>What's new and what changed in 2.6</title> + +<itemizedlist mark="bullet"> + +<listitem><para> +New API: pthread_getname_np, pthread_setname_np. +</para></listitem> + +</itemizedlist> + +<sect2> + <sect2 id="ov-new2.5"><title>What's new and what changed in 2.5</title> <itemizedlist mark="bullet"> diff --git a/winsup/doc/posix.xml b/winsup/doc/posix.xml index 83fa768..d502e30 100644 --- a/winsup/doc/posix.xml +++ b/winsup/doc/posix.xml @@ -1291,6 +1291,8 @@ also IEEE Std 1003.1-2008 (POSIX.1-2008).</para> pow10l ppoll pthread_getattr_np + pthread_getname_np + pthread_setname_np pthread_sigqueue ptsname_r putwc_unlocked -- 2.8.3
