Re: [Crash-utility] [PATCH] sial: Fix processing of bitfields on bigendian systems

ACK - and thanks!

> -----Original Message----- > From: crash-utility-bounces(a)redhat.com [mailto:crash-utility- > bounces(a)redhat.com] On Behalf Of Michael Holzheu > Sent: Wednesday, September 16, 2009 1:45 PM > To: Chouinard, Luc > Cc: wein(a)de.ibm.com; crash > Subject: [Crash-utility] [PATCH] sial: Fix processing of bitfields on > bigendian systems > > Hi Luc, > > The processing of bit fields on big endian systems in sial is currently > broken, because the bits are not copied to the correct position and are > not shifted the right way. > > To fix this, the following patch does the processing on big endian > systems as follows: > 1. sial_exemem(): Copy complete bit field to the "end" (right) of the > long long variable. > 2. get_bit_value(): Shift the bits of the bit field member right to > the "end" of the long long variable. This results in the value of > the requested bitfield member. > > Michael > --- > extensions/libsial/sial_member.c | 7 +++++-- > extensions/libsial/sial_type.c | 6 +++++- > 2 files changed, 10 insertions(+), 3 deletions(-) > > Index: crash-4.0.9/extensions/libsial/sial_member.c > =================================================================== > --- crash-4.0.9.orig/extensions/libsial/sial_member.c > +++ crash-4.0.9/extensions/libsial/sial_member.c > @@ -236,10 +236,13 @@ srcpos_t p; > } > /* bit field gymnastic */ > else if(stm->m.nbits) { > - > ull value=0; > + void *target = &value; > + > + if (__BYTE_ORDER != __LITTLE_ENDIAN) > + target = target + (sizeof(value) - stm->m.size); > > - API_GETMEM(m->mem+stm->m.offset, &value, stm->m.size); > + API_GETMEM(m->mem+stm->m.offset, target, stm->m.size); > get_bit_value(value, stm->m.nbits, stm->m.fbit, stm- > >m.size, v); > /* no mempos for bit fields ... */ > > Index: crash-4.0.9/extensions/libsial/sial_type.c > =================================================================== > --- crash-4.0.9.orig/extensions/libsial/sial_type.c > +++ crash-4.0.9/extensions/libsial/sial_type.c > @@ -287,7 +287,11 @@ get_bit_value(ull val, int nbits, int bo > else { > mask = ((1 << nbits) - 1); > } > - val = val >> boff; > + > + if (__BYTE_ORDER == __LITTLE_ENDIAN) > + val = val >> boff; > + else > + val = val >> (vnbits - boff - nbits); > val &= mask; > > if(issigned(v)) { > > > -- > Crash-utility mailing list > Crash-utility(a)redhat.com > https://www.redhat.com/mailman/listinfo/crash-utility -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility