From 44d28e55121f9a7d736df59c09b963e17c8c4cfa Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sat, 24 May 2014 20:39:46 -0400 Subject: [PATCH] overhaul siginfo_t definition in signal.h the main motivation for this change is that, with the previous definition, it was arguably illegal, in standard C, to initialize both si_value and si_pid/si_uid with designated initializers, due to the rule that only one member of a union can have an initializer. whether or not this affected real-world application code, it affected some internal code, and clang was producing warnings (and possibly generating incorrect code). the new definition uses a more complex hierarchy of structs and unions to avoid the need to initialize more than one member of a single union in usage cases that make sense. further work would be needed to eliminate even the ones with no practical applications. at the same time, some fixes are made to the exposed names for nonstandard fields, to match what software using them expects. --- include/signal.h | 51 ++++++++++++++++++++++++++---------------------- 1 file changed, 28 insertions(+), 23 deletions(-) diff --git a/include/signal.h b/include/signal.h index 3fb21b2a..c36e4d59 100644 --- a/include/signal.h +++ b/include/signal.h @@ -89,19 +89,24 @@ typedef struct { union { char __pad[128 - 2*sizeof(int) - sizeof(long)]; struct { - pid_t si_pid; - uid_t si_uid; - union sigval si_sigval; - } __rt; - struct { - unsigned int si_timer1, si_timer2; - } __timer; - struct { - pid_t si_pid; - uid_t si_uid; - int si_status; - clock_t si_utime, si_stime; - } __sigchld; + union { + struct { + pid_t si_pid; + uid_t si_uid; + } __piduid; + struct { + int si_timerid; + int si_overrun; + } __timer; + } __first; + union { + union sigval si_value; + struct { + int si_status; + clock_t si_utime, si_stime; + } __sigchld; + } __second; + } __si_common; struct { void *si_addr; short si_addr_lsb; @@ -117,20 +122,20 @@ typedef struct { } __sigsys; } __si_fields; } siginfo_t; -#define si_pid __si_fields.__sigchld.si_pid -#define si_uid __si_fields.__sigchld.si_uid -#define si_status __si_fields.__sigchld.si_status -#define si_utime __si_fields.__sigchld.si_utime -#define si_stime __si_fields.__sigchld.si_stime -#define si_value __si_fields.__rt.si_sigval +#define si_pid __si_fields.__si_common.__first.__piduid.si_pid +#define si_uid __si_fields.__si_common.__first.__piduid.si_uid +#define si_status __si_fields.__si_common.__second.__sigchld.si_status +#define si_utime __si_fields.__si_common.__second.__sigchld.si_utime +#define si_stime __si_fields.__si_common.__second.__sigchld.si_stime +#define si_value __si_fields.__si_common.__second.si_value #define si_addr __si_fields.__sigfault.si_addr #define si_addr_lsb __si_fields.__sigfault.si_addr_lsb #define si_band __si_fields.__sigpoll.si_band #define si_fd __si_fields.__sigpoll.si_fd -#define si_timer1 __si_fields.__timer.si_timer1 -#define si_timer2 __si_fields.__timer.si_timer2 -#define si_ptr __si_fields.__rt.si_sigval.sival_ptr -#define si_int __si_fields.__rt.si_sigval.sival_int +#define si_timerid __si_fields.__si_common.__first.__timer.si_timerid +#define si_overrun __si_fields.__si_common.__first.__timer.si_overrun +#define si_ptr si_value.sival_ptr +#define si_int si_value.sival_int #define si_call_addr __si_fields.__sigsys.si_call_addr #define si_syscall __si_fields.__sigsys.si_syscall #define si_arch __si_fields.__sigsys.si_arch -- 2.25.1