patch fixing 297991: mmap changing a file descriptor current position
Bug caused by the following problem:
for each mmap, Valgrind reads the 1st 1024 bytes to detect
if this is an mmap-ed file containing debug info to decode.
Reading this 1Kb is done with VG_(pread). VG_(pread) should be
the equivalent of syscall pread but on linux, it is implemented as
a seek+read.
The patch implements VG_(pread) in terms of the underlying pread syscall.
Test mmap_fcntl_bug.c completed to also verify the fd current position
before and after the mmap.
tested on linux x86/amd64/ppc32/ppc64/s390.
(not tested on Darwin)
(manually tested on arm-android)
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@12504 a5019735-40e9-0310-863c-91ae7b9d1cf9
3 files changed
