From patchwork Fri Aug 11 18:12:29 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joseph Myers X-Patchwork-Id: 22104 Received: (qmail 81915 invoked by alias); 11 Aug 2017 18:12:40 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 81900 invoked by uid 89); 11 Aug 2017 18:12:39 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-24.4 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RCVD_IN_DNSWL_NONE, SPF_PASS, URIBL_RED autolearn=ham version=3.3.2 spammy=1993 X-HELO: relay1.mentorg.com Date: Fri, 11 Aug 2017 18:12:29 +0000 From: Joseph Myers To: Subject: Fix sigval namespace (bug 21944) Message-ID: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 X-ClientProxiedBy: svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) To svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) XPG4.2 defines the siginfo_t type, but not union sigval or its contents (which were added in the 1993 edition of POSIX.1), resulting in namespace violations for sigval, sival_int and sival_ptr for signal.h and sys/wait.h for that standard because those headers incorrectly expose those names in that case. This patch fixes this problem. The public type in this case is union sigval, but various places in the headers use the sigval_t name for it; direct uses of union sigval are already properly guarded or in headers not in XPG4.2. Now, sigval_t, although not a standard name, does seem to be widely used outside glibc. The approach taken by this patch is to make installed headers use the name __sigval_t instead. __sigval_t is then defined to either union sigval or union __sigval (where union __sigval has __-prefixed member names as well), depending on whether there are any namespace issues with the union sigval name and its members. In the case where union __sigval is used, sigval_t is not defined at all, to avoid the problem of sigval_t having a C++ mangled name that depends on feature test macros. sigval_t is still defined by signal.h if __USE_MISC (reflecting the nonstandard nature of that name). Tested for x86_64. 2017-08-11 Joseph Myers [BZ #21944] * signal/bits/types/__sigval_t.h: New file. * signal/Makefile (headers): Add bits/types/__sigval_t.h. * signal/bits/types/sigval_t.h: Include and define sigval_t using __sigval_t. * include/bits/types/__sigval_t.h: New file. * bits/types/sigevent_t.h: Include instead of . (struct sigevent): Use __sigval_t instead of sigval_t. * bits/types/siginfo_t.h: Include instead of . (siginfo_t): Use __sigval_t instead of sigval_t. * sysdeps/unix/sysv/linux/bits/types/sigevent_t.h: Include instead of . (struct sigevent): Use __sigval_t instead of sigval_t. * sysdeps/unix/sysv/linux/bits/types/siginfo_t.h: Include instead of . (siginfo_t): Use __sigval_t instead of sigval_t. * signal/signal.h [__USE_MISC]: Include . diff --git a/bits/types/sigevent_t.h b/bits/types/sigevent_t.h index 7b8cb05..5611268 100644 --- a/bits/types/sigevent_t.h +++ b/bits/types/sigevent_t.h @@ -2,15 +2,15 @@ #define __sigevent_t_defined 1 #include -#include +#include /* Structure to transport application-defined values with signals. */ typedef struct sigevent { - sigval_t sigev_value; + __sigval_t sigev_value; int sigev_signo; int sigev_notify; - void (*sigev_notify_function) (sigval_t); /* Function to start. */ + void (*sigev_notify_function) (__sigval_t); /* Function to start. */ void *sigev_notify_attributes; /* Really pthread_attr_t.*/ } sigevent_t; diff --git a/bits/types/siginfo_t.h b/bits/types/siginfo_t.h index ab6bf18..1ac2a98 100644 --- a/bits/types/siginfo_t.h +++ b/bits/types/siginfo_t.h @@ -2,7 +2,7 @@ #define __siginfo_t_defined 1 #include -#include +#include typedef struct siginfo { @@ -15,7 +15,7 @@ typedef struct siginfo void *si_addr; /* Address of faulting instruction. */ int si_status; /* Exit value or signal. */ long int si_band; /* Band event for SIGPOLL. */ - sigval_t si_value; /* Signal value. */ + __sigval_t si_value; /* Signal value. */ } siginfo_t; #endif diff --git a/include/bits/types/__sigval_t.h b/include/bits/types/__sigval_t.h new file mode 100644 index 0000000..62f8e48 --- /dev/null +++ b/include/bits/types/__sigval_t.h @@ -0,0 +1 @@ +#include diff --git a/signal/Makefile b/signal/Makefile index 8c9a7d1..a6a1289 100644 --- a/signal/Makefile +++ b/signal/Makefile @@ -30,7 +30,8 @@ headers := signal.h sys/signal.h \ bits/types/__sigset_t.h bits/types/sig_atomic_t.h \ bits/types/sigevent_t.h bits/types/siginfo_t.h \ bits/types/sigset_t.h bits/types/sigval_t.h \ - bits/types/stack_t.h bits/types/struct_sigstack.h + bits/types/stack_t.h bits/types/struct_sigstack.h \ + bits/types/__sigval_t.h routines := signal raise killpg \ sigaction sigprocmask kill \ diff --git a/signal/bits/types/__sigval_t.h b/signal/bits/types/__sigval_t.h new file mode 100644 index 0000000..90cba5b --- /dev/null +++ b/signal/bits/types/__sigval_t.h @@ -0,0 +1,23 @@ +#ifndef ____sigval_t_defined +#define ____sigval_t_defined + +/* Type for data associated with a signal. */ +#ifdef __USE_POSIX199309 +union sigval +{ + int sival_int; + void *sival_ptr; +}; + +typedef union sigval __sigval_t; +#else +union __sigval +{ + int __sival_int; + void *__sival_ptr; +}; + +typedef union __sigval __sigval_t; +#endif + +#endif diff --git a/signal/bits/types/sigval_t.h b/signal/bits/types/sigval_t.h index 666598f..a05d7f4 100644 --- a/signal/bits/types/sigval_t.h +++ b/signal/bits/types/sigval_t.h @@ -1,13 +1,18 @@ #ifndef __sigval_t_defined #define __sigval_t_defined -/* Type for data associated with a signal. */ -union sigval -{ - int sival_int; - void *sival_ptr; -}; - -typedef union sigval sigval_t; +#include + +/* To avoid sigval_t (not a standard type name) having C++ name + mangling depending on whether the selected standard includes union + sigval, it should not be defined at all when using a standard for + which the sigval name is not reserved; in that case, headers should + not include and should use only the + internal __sigval_t name. */ +#ifndef __USE_POSIX199309 +# error "sigval_t defined for standard not including union sigval" +#endif + +typedef __sigval_t sigval_t; #endif diff --git a/signal/signal.h b/signal/signal.h index c8f6100..416c5a2 100644 --- a/signal/signal.h +++ b/signal/signal.h @@ -58,6 +58,10 @@ typedef __uid_t uid_t; # include #endif +#ifdef __USE_MISC +# include +#endif + #ifdef __USE_POSIX199309 # include # include diff --git a/sysdeps/unix/sysv/linux/bits/types/sigevent_t.h b/sysdeps/unix/sysv/linux/bits/types/sigevent_t.h index 0d4857b..e8b28de 100644 --- a/sysdeps/unix/sysv/linux/bits/types/sigevent_t.h +++ b/sysdeps/unix/sysv/linux/bits/types/sigevent_t.h @@ -3,7 +3,7 @@ #include #include -#include +#include #define __SIGEV_MAX_SIZE 64 #if __WORDSIZE == 64 @@ -21,7 +21,7 @@ typedef union pthread_attr_t pthread_attr_t; /* Structure to transport application-defined values with signals. */ typedef struct sigevent { - sigval_t sigev_value; + __sigval_t sigev_value; int sigev_signo; int sigev_notify; @@ -35,7 +35,7 @@ typedef struct sigevent struct { - void (*_function) (sigval_t); /* Function to start. */ + void (*_function) (__sigval_t); /* Function to start. */ pthread_attr_t *_attribute; /* Thread attributes. */ } _sigev_thread; } _sigev_un; diff --git a/sysdeps/unix/sysv/linux/bits/types/siginfo_t.h b/sysdeps/unix/sysv/linux/bits/types/siginfo_t.h index bed6914..33766d1 100644 --- a/sysdeps/unix/sysv/linux/bits/types/siginfo_t.h +++ b/sysdeps/unix/sysv/linux/bits/types/siginfo_t.h @@ -3,7 +3,7 @@ #include #include -#include +#include #define __SI_MAX_SIZE 128 #if __WORDSIZE == 64 @@ -64,7 +64,7 @@ typedef struct { int si_tid; /* Timer ID. */ int si_overrun; /* Overrun count. */ - sigval_t si_sigval; /* Signal value. */ + __sigval_t si_sigval; /* Signal value. */ } _timer; /* POSIX.1b signals. */ @@ -72,7 +72,7 @@ typedef struct { __pid_t si_pid; /* Sending process ID. */ __uid_t si_uid; /* Real user ID of sending process. */ - sigval_t si_sigval; /* Signal value. */ + __sigval_t si_sigval; /* Signal value. */ } _rt; /* SIGCHLD. */