# Copyright (C) 2010-2020 Free Software Foundation, Inc.
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
# Return nul-terminated string read from section SECTION of EXEC. Return ""
# if no such section or nul-terminated string was found. Function is useful
# for sections ".interp" or ".gnu_debuglink".
proc section_get {exec section} {
global subdir
set tmp [standard_output_file section_get.tmp]
set objcopy_program [gdb_find_objcopy]
set command "exec $objcopy_program -O binary --set-section-flags $section=A --change-section-address $section=0 -j $section $exec $tmp"
verbose -log "command is $command"
set result [catch $command output]
verbose -log "result is $result"
verbose -log "output is $output"
if {$result == 1} {
return ""
}
set fi [open $tmp]
fconfigure $fi -translation binary
set data [read $fi]
close $fi
file delete $tmp
# .interp has size $len + 1 but .gnu_debuglink contains garbage after \000.
set len [string first \000 $data]
if {$len < 0} {
verbose -log "section $section not found"
return ""
}
set retval [string range $data 0 [expr $len - 1]]
verbose -log "section $section is <$retval>"
return $retval
}
# Resolve symlinks.
proc symlink_resolve {file} {
set loop 0
while {[file type $file] == "link"} {
set target [file readlink $file]
if {[file pathtype $target] == "relative"} {
set src2 [file dirname $file]/$target
} else {
set src2 $target
}
verbose -log "Resolved symlink $file targetting $target as $src2"
set file $src2
set loop [expr $loop + 1]
if {$loop > 30} {
fail "looping symlink resolution for $file"
return ""
}
}
return $file
}
# Copy SRC to DEST, resolving any symlinks in SRC. Return nonzero iff
# the copy was succesful.
#
# This function is guaranteed to never raise any exception, even when the copy
# fails.
proc file_copy {src dest} {
set src [symlink_resolve $src]
# Test name would contain unstable directory name for symlink-unresolved
# $src.
set test "copy [file tail $src] to [file tail $dest]"
set command "file copy -force -- $src $dest"
verbose -log "command is $command"
if [catch $command] {
fail $test
return 0
} else {
pass $test
return 1
}
}
# Wrap function build_executable so that the resulting executable is fully
# self-sufficient (without dependencies on system libraries). Parameter
# INTERP may be used to specify a loader (ld.so) to be used that is
# different from the default system one. INTERP can be set to "no" if no ld.so
# copy should be made. Libraries on which the executable depends are copied
# into directory DIR. Default DIR value to
# `${objdir}/${subdir}/${EXECUTABLE}.d'.
#
# In case of success, return a string containing the arguments to be used
# in order to perform a prelink of the executable obtained. Return the
# empty string in case of failure.
#
# This can be useful when trying to prelink an executable which might
# depend on system libraries. To properly prelink an executable, all
# of its dynamically linked libraries must be prelinked as well. If
# the executable depends on some system libraries, we may not have
# sufficient write priviledges on these files to perform the prelink.
# This is why we make a copy of these shared libraries, and link the
# executable against these copies instead.
#
# Function recognizes only libraries listed by `ldd' after
# its ` => ' separator. That means $INTERP and any libraries not being linked
# with -Wl,-soname,NAME.so are not copied.
proc build_executable_own_libs {testname executable sources options {interp ""} {dir ""}} {
global subdir
if { ![isnative] } {
error "This proc can be only used for native target."
}
if {[build_executable $testname $executable $sources $options] == -1} {
return ""
}
set binfile [standard_output_file ${executable}]
set ldd [gdb_find_ldd]
set command "$ldd $binfile"
set test "ldd $executable"
set result [catch "exec $command" output]
verbose -log "result of $command is $result"
verbose -log "output of $command is $output"
if {$result != 0 || $output == ""} {
fail $test
} else {
pass $test
}
# gdb testsuite will put there also needless -lm.
set test "$test output contains libs"
set libs [regexp -all -inline -line {^.* => (/[^ ]+).*$} $output]
if {[llength $libs] == 0} {
fail $test
} else {
pass $test
}
if {$dir == ""} {
set dir ${binfile}.d
}
file delete -force -- $dir
file mkdir $dir
if {$interp == ""} {
set interp_system [section_get $binfile .interp]
if {$interp_system == ""} {
fail "$test could not find .interp"
} else {
set interp ${dir}/[file tail $interp_system]
file_copy $interp_system $interp
}
}
if {$interp == "no"} {
set interp ""
}
set dests {}
foreach {trash abspath} $libs {
set dest "$dir/[file tail $abspath]"
file_copy $abspath $dest
lappend dests $dest
}
# Do not lappend it so that "-rpath $dir" overrides any possible "-rpath"s
# specified by the caller to be able to link it for ldd" above.
set options [linsert $options 0 "ldflags=-Wl,-rpath,$dir"]
if {$interp != ""} {
set options [linsert $options 0 "ldflags=-Wl,--dynamic-linker,$interp"]
}
if {[build_executable $testname $executable $sources $options] == -1} {
return ""
}
set prelink_args "--ld-library-path=$dir $binfile [concat $dests]"
if {$interp != ""} {
set prelink_args "--dynamic-linker=$interp $prelink_args $interp"
}
return $prelink_args
}
# Unprelink ARG. Reported test name can be specified by NAME. Return non-zero
# on success, zero on failure.
proc prelink_no {arg {name {}}} {
if {$name == ""} {
set name [file tail $arg]
}
set test "unprelink $name"
set command "exec /usr/sbin/prelink -uN $arg"
verbose -log "command is $command"
set result [catch $command output]
verbose -log "result is $result"
verbose -log "output is $output"
if {$result == 1 && [regexp {^(couldn't execute "/usr/sbin/prelink[^\r\n]*": no such file or directory\n?)*$} $output]} {
# Without prelink, at least verify that all the binaries do not
# contain the ".gnu.prelink_undo" section (which would mean that they
# have already been prelinked).
set test "$test (missing /usr/sbin/prelink)"
foreach bin [split $arg] {
if [string match "-*" $bin] {
# Skip prelink options.
continue
}
set readelf_program [gdb_find_readelf]
set command "exec $readelf_program -WS $bin"
verbose -log "command is $command"
set result [catch $command output]
verbose -log "result is $result"
verbose -log "output is $output"
if {$result != 0 || [string match {* .gnu.prelink_undo *} $output]} {
fail "$test ($bin is already prelinked)"
return 0
}
}
pass $test
return 1
}
if {$result == 0 && $output == ""} {
verbose -log "$name has been now unprelinked"
set command "exec /usr/sbin/prelink -uN $arg"
verbose -log "command is $command"
set result [catch $command output]
verbose -log "result is $result"
verbose -log "output is $output"
}
# Last line does miss the trailing \n. There can be multiple such messages
# as ARG may list multiple files.
if {$result == 1 && [regexp {^([^\r\n]*prelink[^\r\n]*: [^ ]* does not have .gnu.prelink_undo section\n?)*$} $output]} {
pass $test
return 1
} else {
fail $test
return 0
}
}
# Prelink ARG. Reported test name can be specified by NAME. Return non-zero
# on success, zero on failure.
proc prelink_yes {arg {name ""}} {
if {$name == ""} {
set name [file tail $arg]
}
# Try to unprelink it first so that, if it has been already prelinked
# before, we get a different address now, making the new result unaffected
# by any previous prelinking.
if ![prelink_no $arg "$name pre-unprelink"] {
return 0
}
set test "prelink $name"
# `--no-exec-shield' is for i386, where prelink in the exec-shield mode is
# forced to push all the libraries tight together, in order to fit into
# the first two memory areas (either the ASCII Shield area or at least
# below the executable). If the prelink was performed in exec-shield
# mode, prelink could have no choice on how to randomize the single new
# unprelinked library address without wasting space in the first one/two
# memory areas. In such case prelink could place $ARG repeatedly at the
# same place and we could have false prelink results on
# gdb.base/prelink.exp and others. To prevent this from happening, we use
# the --no-exec-shield switch. This may have some consequences in terms
# of security, but we do not care in our case.
set command "exec /usr/sbin/prelink -qNR --no-exec-shield $arg"
verbose -log "command is $command"
set result [catch $command output]
verbose -log "result is $result"
verbose -log "output is $output"
if {$result == 1 && [regexp {^(couldn't execute "/usr/sbin/prelink[^\r\n]*": no such file or directory\n?)*$} $output]} {
set test "$test (missing /usr/sbin/prelink)"
# We could not find prelink. We could check whether $args is already
# prelinked but we don't, because:
# - It is unlikely that someone uninstalls prelink after having
# prelinked the system ld.so;
# - We still cannot change its prelinked address.
# Therefore, we just skip the test.
xfail $test
return 0
}
if {$result == 1 && [regexp {DWARF [^\r\n]* unhandled} $output]} {
# Prelink didn't understand the version of dwarf present.
unsupported "$test (dwarf version unhandled)"
return 0
}
if {$result == 0 && $output == ""} {
pass $test
return 1
} elseif {$result == 1 \
&& [string match -nocase "*: Not enough room to add .dynamic entry" $output]} {
# Linker should have reserved some entries for prelink.
xfail $test
return 0
} else {
fail $test
return 0
}
}