Re: [PATCH v3] gdb: Introduce user-friendly namespace identifier for "info shared"

[Guinevere Larsen <guinevere@redhat.com>]

Linaro CI told me there was a problem in the test case in here (thanks 
again, linaro!). More inlined
> diff --git a/gdb/testsuite/gdb.base/dlmopen-ns-ids.exp b/gdb/testsuite/gdb.base/dlmopen-ns-ids.exp
> new file mode 100644
> index 00000000000..18856dca7cc
> --- /dev/null
> +++ b/gdb/testsuite/gdb.base/dlmopen-ns-ids.exp
> @@ -0,0 +1,106 @@
> +# This testcase is part of GDB, the GNU debugger.
> +#
> +# Copyright 2025 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/>.
> +#
> +#
> +# Test several things related to handling linker namespaces:
> +# * That the user-facing namespace ID is consistent;
> +
> +require allow_dlmopen_tests
> +
> +standard_testfile -main.c -lib.c
> +
> +set srcfile_lib $srcfile2
> +set binfile_lib [standard_output_file dlmopen-lib.so]
> +
> +if { [build_executable "build shlib" $binfile_lib $srcfile_lib \
> +	  [list debug shlib]] == -1 } {
> +    return
> +}
> +
> +if { [build_executable "failed to build" $testfile $srcfile \
> +	  [list additional_flags=-DDSO_NAME=\"$binfile_lib\" \
> +	       shlib_load debug]] } {
> +    return
> +}
> +
> +# Run the command "info sharedlibrary" and get the first namespace
> +# for the so
> +proc get_first_so_ns {} {
> +    set ns -1
> +    gdb_test_multiple "info sharedlibrary" "get SO namespace" -lbl {
> +	-re "From\\s+To\\s+\(NS\\s+\)?Syms\\s+Read\\s+Shared Object Library\r\n" {
> +	    exp_continue
> +	}
> +	-re "^$::hex\\s+$::hex\\s+\[\[($::decimal)\]\]\\s+\[^\r\n]+$::binfile_lib.*" {

Turns out the literal [ and ] should be triple escaped here. I've fixed 
thios locally

> +	    set ns $expect_out(1,string)
> +	}
> +	-re "^$::gdb_prompt $" {
> +	}
> +	-re "^\[^\r\n\]+\r\n" {
> +	    exp_continue
> +	}
> +    }
> +    return $ns
> +}
> +
> +# Run the tests relating to the command "info sharedlibrary", to
> +# verify that the namespace ID is consistent.
> +proc test_info_shared {} {
> +    clean_restart $::binfile
> +
> +    if { ![runto_main] } {
> +	return
> +    }
> +
> +    # First test that we don't print a namespace column at the start.
> +    gdb_test "info sharedlibrary" \
> +	"From\\s+To\\s+Syms\\s+Read\\s+Shared Object Library.*" \
> +	"before loading anything"
> +
> +    gdb_breakpoint [gdb_get_line_number "TAG: first dlclose"]
> +    gdb_continue_to_breakpoint "TAG: first dlclose"
> +
> +    # Next, test that we *do* print a namespace column after loading SOs.
> +    gdb_test "info sharedlibrary" \
> +	"From\\s+To\\s+NS\\s+Syms\\s+Read\\s+Shared Object Library.*" \
> +	"after loading everything"
> +
> +    gdb_assert {[get_first_so_ns] == 1} "before closing any library"
> +
> +    gdb_test "next" ".*second dlclose.*" "close first library"
> +    gdb_assert {[get_first_so_ns] == 2} "after closing one library"
> +
> +    gdb_test "next" ".*third dlclose.*" "close second library"
> +    gdb_assert {[get_first_so_ns] == 3} "before closing two libraries"
> +
> +    gdb_breakpoint [gdb_get_line_number "TAG: fourth dlclose"]
> +    gdb_continue_to_breakpoint "TAG: fourth dlclose"
> +    # As of writing this test, glibc's LMID is just an index on an array of
> +    # namespaces.  After closing a namespace, requesting a new one will
> +    # return the index of the lowest-closed namespace, so this will likely
> +    # be namespace 1, and because of glibc's reuse of the r_debug object,
> +    # GDB should be able to assign the same number.
> +    gdb_assert {[get_first_so_ns] == [get_integer_valueof "lmid" "-1"]} \
> +	"reopen a namespace"
> +
> +    gdb_test "next" ".*return 0.*" "final namespace inactive"
> +    gdb_test "info sharedlibrary" \
> +	"From\\s+To\\s+Syms\\s+Read\\s+Shared Object Library.*" \
> +	"after unloading everything"
> +}
> +
> +test_info_shared

-- 
Cheers,
Guinevere Larsen
She/Her/Hers