Re: git: c29cba408d19 - main - stand: Narrow the 'signal emulation' we provide
Date: Wed, 20 Nov 2024 03:55:57 UTC
On 20 Nov 2024, at 03:35, Warner Losh <imp@FreeBSD.org> wrote: > > The branch main has been updated by imp: > > URL: https://cgit.FreeBSD.org/src/commit/?id=c29cba408d197ed2c267d0605e4225bb54153e01 > > commit c29cba408d197ed2c267d0605e4225bb54153e01 > Author: Warner Losh <imp@FreeBSD.org> > AuthorDate: 2024-11-20 03:05:11 +0000 > Commit: Warner Losh <imp@FreeBSD.org> > CommitDate: 2024-11-20 03:24:41 +0000 > > stand: Narrow the 'signal emulation' we provide > > We only need to provide sig_atomic_t in emulation. However, including > machine/signal.h brings in too much namespace pollution related to > signals. Instead, define sig_atomic_t as long. Setting long is async > atomic on all platforms (though powerpc64 defines it to an int), though > that doesn't matter since the boot loader doesn't use signals. > > Sponsored by: Netflix > --- > stand/libsa/stand.h | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/stand/libsa/stand.h b/stand/libsa/stand.h > index 260defa3a33d..e1188fb73a26 100644 > --- a/stand/libsa/stand.h > +++ b/stand/libsa/stand.h > @@ -82,8 +82,13 @@ > #define EOFFSET (ELAST+8) /* relative seek not supported */ > #define ESALAST (ELAST+8) /* */ > > -/* Partial signal emulation for sig_atomic_t */ > -#include <machine/signal.h> > +/* > + * LUA needs sig_atomic_t. This is defined to be long or int on all our > + * platforms. On all but powerpc, these are all the same thing as long. 64-bit > + * powerpc defines this as int, but long can also be accessed atomically. It's > + * also OK because we don't have signal handlers in the boot loader. > + */ Presumably an oversight when adding the powerpc64* ports :( Probably we should fix this by taking advantage of being able to break ABI for tier 2 architectures between major versions. Shame it wasn’t done the same time as ELFv1 -> ELFv2. We fixed riscv and arm64’s SIG_ATOMIC_MIN/MAX recently, but the underlying types were still long in that case, thankfully. Jess > +typedef long sig_atomic_t; > > __BEGIN_DECLS >