From 355b5406fafe0d45285e70a0b01d5e674d6a2c16 Mon Sep 17 00:00:00 2001 From: Michael Sevakis Date: Mon, 28 Apr 2014 09:15:06 -0400 Subject: Make errno a thread-local variable. errno is supposed to be thread local and we do that here in a rather makeshift way by implementing a function that returns a pointer to the __errno variable in the thread block. If more serious TLS is required, perhaps it would be worthwhile implementing it using the linker and the "__thread" storage attribute. That's a bit overkill just for this. I'm also not liking what I saw the compiler producing. Change-Id: I03bc0bd6a89f6e3d6bae7653284ee01054614f9a Reviewed-on: http://gerrit.rockbox.org/803 Reviewed-by: Michael Sevakis Tested: Michael Sevakis --- firmware/kernel/include/thread.h | 1 + firmware/libc/errno.c | 6 +++++- firmware/libc/include/errno.h | 6 ++++-- 3 files changed, 10 insertions(+), 3 deletions(-) (limited to 'firmware') diff --git a/firmware/kernel/include/thread.h b/firmware/kernel/include/thread.h index 9cc33b2..8c13b46 100644 --- a/firmware/kernel/include/thread.h +++ b/firmware/kernel/include/thread.h @@ -210,6 +210,7 @@ struct thread_entry volatile intptr_t retval; /* Return value from a blocked operation/ misc. use */ #endif + int __errno; /* Thread error number (errno tls) */ #ifdef HAVE_PRIORITY_SCHEDULING /* Priority summary of owned objects that support inheritance */ struct blocker *blocker; /* Pointer to blocker when this thread is blocked diff --git a/firmware/libc/errno.c b/firmware/libc/errno.c index 6e7bb62..2e3cd90 100644 --- a/firmware/libc/errno.c +++ b/firmware/libc/errno.c @@ -1 +1,5 @@ -int errno; +#include "thread.h" +int * __errno(void) +{ + return &thread_self_entry()->__errno; +} diff --git a/firmware/libc/include/errno.h b/firmware/libc/include/errno.h index 6a24a19..9df261d 100644 --- a/firmware/libc/include/errno.h +++ b/firmware/libc/include/errno.h @@ -10,10 +10,12 @@ #ifndef _SYS_ERRNO_H_ +extern int * __errno(void); + #ifdef PLUGIN -#define errno (*rb->__errno) +#define errno (*rb->__errno()) #else -extern int errno; +#define errno (*__errno()) #endif #define EPERM 1 /* Not super-user */ -- cgit v1.1