[1/2] Attach to test in container from debugglibc.sh

  From: "Gabriel F. T. Gomes" <gabrielftg@linux.ibm.com>

Some test cases are meant to be ran inside the container infrastructure
and make check automatically runs them as such.  However, running a
single test case in a container without make check is useful.

This patch adds a new --tool option to testrun.sh that makes this easy,
as well as it adds a new option (-c or --in-container) to debugglibc.sh,
which causes the program under test to be ran in a container (with
WAIT_FOR_DEBUGGER=1), then automatically attaches GDB to it.

Automatically detecting if a test case is supposed to be ran inside a
container is harder (if not impossible), as Carlos pointed out [1],
however, this patch makes it easier to do it manually:

  Using testrun.sh with containerized test:

    $ ./testrun.sh --tool=container /absolute/path/to/program

  Using debugglibc.sh with containerized test:

    $ ./debugglibc.sh -c /absolute/path/to/program

Note: running these commands with relative paths causes error and
warning messages to be displayed, although the test case might succeed.

For example, with relative path:

  $ ./testrun.sh --tool=container elf/tst-ldconfig-bad-aux-cache
  error: subprocess failed: execv
  error:   unexpected error output from subprocess
  /sbin/ldconfig: Warning: ignoring configuration file that cannot be opened: /etc/ld.so.conf: No such file or directory
  info: f    0    1064   /var/cache/ldconfig/aux-cache            20 aux-cache
  [...]

Whereas with absolute paths, the errors and warnings are gone:

  $ ./testrun.sh --tool=container $PWD/elf/tst-ldconfig-bad-aux-cache
  info: f    0    1064   /var/cache/ldconfig/aux-cache            20 aux-cache
  [...]

[1] https://sourceware.org/ml/libc-alpha/2019-11/msg00873.html
---
 Makefile | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)
  

On 12/3/19 9:36 PM, Gabriel F. T. Gomes wrote:
> From: "Gabriel F. T. Gomes" <gabrielftg@linux.ibm.com>

This is much better than what we have, thank you for implementing this!

We can always improve this as time goes on.

LGTM.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

> Some test cases are meant to be ran inside the container infrastructure
> and make check automatically runs them as such.  However, running a
> single test case in a container without make check is useful.
> 
> This patch adds a new --tool option to testrun.sh that makes this easy,
> as well as it adds a new option (-c or --in-container) to debugglibc.sh,
> which causes the program under test to be ran in a container (with
> WAIT_FOR_DEBUGGER=1), then automatically attaches GDB to it.
> 
> Automatically detecting if a test case is supposed to be ran inside a
> container is harder (if not impossible), as Carlos pointed out [1],
> however, this patch makes it easier to do it manually:
> 
>   Using testrun.sh with containerized test:
> 
>     $ ./testrun.sh --tool=container /absolute/path/to/program
> 
>   Using debugglibc.sh with containerized test:
> 
>     $ ./debugglibc.sh -c /absolute/path/to/program
> 
> Note: running these commands with relative paths causes error and
> warning messages to be displayed, although the test case might succeed.
> 
> For example, with relative path:
> 
>   $ ./testrun.sh --tool=container elf/tst-ldconfig-bad-aux-cache
>   error: subprocess failed: execv
>   error:   unexpected error output from subprocess
>   /sbin/ldconfig: Warning: ignoring configuration file that cannot be opened: /etc/ld.so.conf: No such file or directory
>   info: f    0    1064   /var/cache/ldconfig/aux-cache            20 aux-cache
>   [...]
> 
> Whereas with absolute paths, the errors and warnings are gone:
> 
>   $ ./testrun.sh --tool=container $PWD/elf/tst-ldconfig-bad-aux-cache
>   info: f    0    1064   /var/cache/ldconfig/aux-cache            20 aux-cache
>   [...]
> 
> [1] https://sourceware.org/ml/libc-alpha/2019-11/msg00873.html
> ---
>  Makefile | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/Makefile b/Makefile
> index fae71aa287..924fdb6c0f 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -181,6 +181,11 @@ case "$$toolname" in
>    valgrind)
>      exec env $(run-program-env) valgrind $(test-via-rtld-prefix) $${1+"$$@"}
>      ;;
> +  container)
> +    exec env $(run-program-env) $(test-via-rtld-prefix) \
> +      $(common-objdir)/support/test-container \
> +      env $(run-program-env) $(test-via-rtld-prefix) $${1+"$$@"}

OK.

> +    ;;
>    *)
>      usage
>      ;;
> @@ -202,6 +207,7 @@ define debugglibc
>  SOURCE_DIR="$(CURDIR)"
>  BUILD_DIR="$(common-objpfx)"
>  CMD_FILE="$(common-objpfx)debugglibc.gdb"
> +CONTAINER=false
>  DIRECT=true
>  SYMBOLSFILE=true
>  unset TESTCASE
> @@ -235,6 +241,9 @@ Options:
>  
>    The following options do not take arguments:
>  
> +  -c, --in-container
> +	Run the test case inside a container and automatically attach
> +	GDB to it.

OK.

>    -i, --no-direct
>  	Selects whether to pass the --direct flag to the program.
>  	--direct is useful when debugging glibc test cases. It inhibits the
> @@ -263,6 +272,9 @@ do
>        ENVVARS="$$2 $$ENVVARS"
>        shift
>        ;;
> +    -c|--in-container)
> +      CONTAINER=true
> +      ;;

OK.

>      -i|--no-direct)
>        DIRECT=false
>        ;;
> @@ -348,6 +360,13 @@ echo "GDB Commands     : $$CMD_FILE"
>  echo "Env vars         : $$ENVVARS"
>  echo
>  
> +if [ "$$CONTAINER" == true ]
> +then
> +# Use testrun.sh to start the test case with WAIT_FOR_DEBUGGER=1, then
> +# automatically attach GDB to it.
> +WAIT_FOR_DEBUGGER=1 $(common-objpfx)testrun.sh --tool=container $${TESTCASE} &
> +gdb -x $${TESTCASE}.gdb

OK. Good use of this infrastructure.

> +else
>  # Start the test case debugging in two steps:
>  #   1. the following command invokes gdb to run the loader;
>  #   2. the commands file tells the loader to run the test case.
> @@ -355,6 +374,7 @@ gdb -q \
>    -x $${CMD_FILE} \
>    -d $${SOURCE_DIR} \
>    $${BUILD_DIR}/elf/ld.so
> +fi

OK.

>  endef
>  
>  # This is another handy script for debugging dynamically linked program
>