[2/2] Add "args" and "env" parameters to DAP launch request

  This patch augments the DAP launch request with some optional new
parameters that let the client control the command-line arguments and
the environment of the inferior.
---
 gdb/doc/gdb.texinfo                | 13 +++++-
 gdb/python/lib/gdb/dap/launch.py   | 20 ++++++++-
 gdb/testsuite/gdb.dap/args-env.c   | 28 ++++++++++++
 gdb/testsuite/gdb.dap/args-env.exp | 90 ++++++++++++++++++++++++++++++++++++++
 gdb/testsuite/lib/dap-support.exp  | 39 +++++++++++++----
 5 files changed, 178 insertions(+), 12 deletions(-)
  

> Date: Tue, 09 May 2023 10:02:00 -0600
> From: Tom Tromey via Gdb-patches <gdb-patches@sourceware.org>
> 
> This patch augments the DAP launch request with some optional new
> parameters that let the client control the command-line arguments and
> the environment of the inferior.
> ---
>  gdb/doc/gdb.texinfo                | 13 +++++-
>  gdb/python/lib/gdb/dap/launch.py   | 20 ++++++++-
>  gdb/testsuite/gdb.dap/args-env.c   | 28 ++++++++++++
>  gdb/testsuite/gdb.dap/args-env.exp | 90 ++++++++++++++++++++++++++++++++++++++
>  gdb/testsuite/lib/dap-support.exp  | 39 +++++++++++++----
>  5 files changed, 178 insertions(+), 12 deletions(-)

Thanks.

> +@item env
> +If provided, this should be an object where each value is a string.

This doesn't say what should those string values be.  Shouldn't they
be of the format "@var{variable}=@var{value}"?

> +The environment of the inferior will be set to exactly as passed in,
> +as if by a sequence of invocations of @code{set environment} and
> +@code{unset environment}.  @xref{Environment}.

This could potentially confuse: if this is equivalent to "set
environment", then the variables are _added_ to the one inherited from
the parent process, no?  Also, when would this be equivalent to "unset
environment"?

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
  

Tom Tromey via Gdb-patches <gdb-patches@sourceware.org> writes:

> This patch augments the DAP launch request with some optional new
> parameters that let the client control the command-line arguments and
> the environment of the inferior.

I haven't followed the DAP additions much, but the code changes in here
look reasonable to me.

Reviewed-By: Andrew Burgess <aburgess@redhat.com>

Thanks,
Andrew




> ---
>  gdb/doc/gdb.texinfo                | 13 +++++-
>  gdb/python/lib/gdb/dap/launch.py   | 20 ++++++++-
>  gdb/testsuite/gdb.dap/args-env.c   | 28 ++++++++++++
>  gdb/testsuite/gdb.dap/args-env.exp | 90 ++++++++++++++++++++++++++++++++++++++
>  gdb/testsuite/lib/dap-support.exp  | 39 +++++++++++++----
>  5 files changed, 178 insertions(+), 12 deletions(-)
>
> diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
> index 8c4177c1901..343612060c6 100644
> --- a/gdb/doc/gdb.texinfo
> +++ b/gdb/doc/gdb.texinfo
> @@ -38998,10 +38998,21 @@ Generally, @value{GDBN} implements the Debugger Adapter Protocol as
>  written.  However, in some cases, extensions are either needed or even
>  expected.
>  
> -@value{GDBN} defines a parameter that can be passed to the
> +@value{GDBN} defines some parameters that can be passed to the
>  @code{launch} request:
>  
>  @table @code
> +@item args
> +If provided, this should be an array of strings.  These strings are
> +provided as command-line arguments to the inferior, as if by
> +@code{set args}.  @xref{Arguments}.
> +
> +@item env
> +If provided, this should be an object where each value is a string.
> +The environment of the inferior will be set to exactly as passed in,
> +as if by a sequence of invocations of @code{set environment} and
> +@code{unset environment}.  @xref{Environment}.
> +
>  @item program
>  If provided, this is a string that specifies the program to use.  This
>  corresponds to the @code{file} command.  @xref{Files}.
> diff --git a/gdb/python/lib/gdb/dap/launch.py b/gdb/python/lib/gdb/dap/launch.py
> index b4102cc28cc..21499a339e1 100644
> --- a/gdb/python/lib/gdb/dap/launch.py
> +++ b/gdb/python/lib/gdb/dap/launch.py
> @@ -13,20 +13,36 @@
>  # You should have received a copy of the GNU General Public License
>  # along with this program.  If not, see <http://www.gnu.org/licenses/>.
>  
> +import gdb
>  from .events import ExecutionInvoker
>  from .server import request, capability
> -from .startup import send_gdb
> +from .startup import send_gdb, in_gdb_thread
>  
>  
>  _program = None
>  
>  
> +@in_gdb_thread
> +def _set_args_env(args, env):
> +    inf = gdb.selected_inferior()
> +    inf.arguments = args
> +    if env is not None:
> +        inf.clear_env()
> +        for name, value in env.items():
> +            inf.set_env(name, value)
> +
> +
> +# Any parameters here are necessarily extensions -- DAP requires this
> +# from implementations.  Any additions or changes here should be
> +# documented in the gdb manual.
>  @request("launch")
> -def launch(*, program=None, **args):
> +def launch(*, program=None, args=[], env=None, **extra):
>      if program is not None:
>          global _program
>          _program = program
>          send_gdb(f"file {_program}")
> +    if len(args) > 0 or env is not None:
> +        send_gdb(lambda: _set_args_env(args, env))
>  
>  
>  @capability("supportsConfigurationDoneRequest")
> diff --git a/gdb/testsuite/gdb.dap/args-env.c b/gdb/testsuite/gdb.dap/args-env.c
> new file mode 100644
> index 00000000000..bc7f1d4b38e
> --- /dev/null
> +++ b/gdb/testsuite/gdb.dap/args-env.c
> @@ -0,0 +1,28 @@
> +/* This testcase is part of GDB, the GNU debugger.
> +
> +   Copyright 2023 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/>.  */
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +
> +int
> +main (int argc, char *argv[])
> +{
> +  const char *value = getenv ("DEI");
> +  const char *no_value = getenv ("NOSUCHVARIABLE");
> +
> +  return 0; /* BREAK */
> +}
> diff --git a/gdb/testsuite/gdb.dap/args-env.exp b/gdb/testsuite/gdb.dap/args-env.exp
> new file mode 100644
> index 00000000000..96fbb28d9ce
> --- /dev/null
> +++ b/gdb/testsuite/gdb.dap/args-env.exp
> @@ -0,0 +1,90 @@
> +# Copyright 2023 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 environment variables and command line arguments via DAP.
> +
> +require allow_dap_tests !use_gdb_stub
> +
> +load_lib dap-support.exp
> +
> +standard_testfile
> +
> +if {[build_executable ${testfile}.exp $testfile] == -1} {
> +    return
> +}
> +
> +if {[dap_launch $testfile {a "b c"} {{DEI something}}] == ""} {
> +    return
> +}
> +
> +set line [gdb_get_line_number "BREAK"]
> +set obj [dap_check_request_and_response "set breakpoint by line number" \
> +	     setBreakpoints \
> +	     [format {o source [o path [%s]] breakpoints [a [o line [i %d]]]} \
> +		  [list s $srcfile] $line]]
> +set line_bpno [dap_get_breakpoint_number $obj]
> +
> +dap_check_request_and_response "start inferior" configurationDone
> +dap_wait_for_event_and_check "inferior started" thread "body reason" started
> +
> +dap_wait_for_event_and_check "stopped at line breakpoint" stopped \
> +    "body reason" breakpoint \
> +    "body hitBreakpointIds" $line_bpno
> +
> +set bt [lindex [dap_check_request_and_response "backtrace" stackTrace \
> +		    {o threadId [i 1]}] \
> +	    0]
> +set frame_id [dict get [lindex [dict get $bt body stackFrames] 0] id]
> +
> +set obj [dap_check_request_and_response \
> +	     "evaluate argc in function" \
> +	     evaluate [format {o expression [s argc] frameId [i %s]} \
> +			   $frame_id]]
> +dap_match_values "argc in function" [lindex $obj 0] \
> +    "body result" 3
> +
> +set obj [dap_check_request_and_response \
> +	     "evaluate first argument in function" \
> +	     evaluate [format {o expression [s {argv[1]}] frameId [i %s]} \
> +			   $frame_id]]
> +set val [dict get [lindex $obj 0] body result]
> +# This ends up with some extra quoting.
> +gdb_assert {[string first "\\\"a\\\"" $val] != -1} \
> +    "first argument in function"
> +
> +set obj [dap_check_request_and_response \
> +	     "evaluate second argument in function" \
> +	     evaluate [format {o expression [s {argv[2]}] frameId [i %s]} \
> +			   $frame_id]]
> +set val [dict get [lindex $obj 0] body result]
> +# This ends up with some extra quoting.
> +gdb_assert {[string first "\\\"b c\\\"" $val] != -1} \
> +    "second argument in function"
> +
> +set obj [dap_check_request_and_response "evaluate value in function" \
> +	     evaluate [format {o expression [s value] frameId [i %s]} \
> +			   $frame_id]]
> +set val [dict get [lindex $obj 0] body result]
> +# This ends up with some extra quoting.
> +gdb_assert {[string first "\\\"something\\\"" $val] != -1} \
> +    "value in function"
> +
> +set obj [dap_check_request_and_response "evaluate no_value in function" \
> +	     evaluate [format {o expression [s no_value] frameId [i %s]} \
> +			   $frame_id]]
> +dap_match_values "no_value in function" [lindex $obj 0] \
> +    "body result" 0
> +
> +dap_shutdown
> diff --git a/gdb/testsuite/lib/dap-support.exp b/gdb/testsuite/lib/dap-support.exp
> index 6bb9b6e6377..ead295bdbfe 100644
> --- a/gdb/testsuite/lib/dap-support.exp
> +++ b/gdb/testsuite/lib/dap-support.exp
> @@ -236,17 +236,38 @@ proc _dap_initialize {name} {
>  # Start gdb, send a DAP initialize request, and then a launch request
>  # specifying FILE as the program to use for the inferior.  Returns the
>  # empty string on failure, or the response object from the launch
> -# request.  After this is called, gdb will be ready to accept
> -# breakpoint requests.  NAME is used as the test name.  It has a
> -# reasonable default but can be overridden in case a test needs to
> -# launch gdb more than once.
> -proc dap_launch {file {name startup}} {
> -    if {[_dap_initialize "$name - initialize"] == ""} {
> +# request.  If specified, ARGS is a list of command-line arguments,
> +# and ENV is a list of pairs of the form {VAR VALUE} that is used to
> +# populate the inferior's environment.  After this is called, gdb will
> +# be ready to accept breakpoint requests.
> +proc dap_launch {file {args {}} {env {}}} {
> +    if {[_dap_initialize "startup - initialize"] == ""} {
>  	return ""
>      }
> -    return [dap_check_request_and_response "$name - launch" launch \
> -		[format {o program [%s]} \
> -		     [list s [standard_output_file $file]]]]
> +    set params "o program"
> +    append params " [format {[%s]} [list s [standard_output_file $file]]]"
> +
> +    if {[llength $args] > 0} {
> +	append params " args"
> +	set arglist ""
> +	foreach arg $args {
> +	    append arglist " \[s [list $arg]\]"
> +	}
> +	append params " \[a $arglist\]"
> +    }
> +
> +    if {[llength $env] > 0} {
> +	append params " env"
> +	set envlist ""
> +	foreach pair $env {
> +	    lassign $pair var value
> +	    append envlist " $var"
> +	    append envlist " [format {[%s]} [list s $value]]"
> +	}
> +	append params " \[o $envlist\]"
> +    }
> +
> +    return [dap_check_request_and_response "startup - launch" launch $params]
>  }
>  
>  # Cleanly shut down gdb.  NAME is used as the test name.
>
> -- 
> 2.40.0
  

>> +@item env
>> +If provided, this should be an object where each value is a string.

Eli> This doesn't say what should those string values be.  Shouldn't they
Eli> be of the format "@var{variable}=@var{value}"?

In JSON an object is a dictionary; so the keys are strings and the
values are as well.  That is it looks like {"variable": "value"}

Tom
  

> From: Tom Tromey <tromey@adacore.com>
> Cc: Tom Tromey <tromey@adacore.com>,  gdb-patches@sourceware.org
> Date: Tue, 16 May 2023 13:06:09 -0600
> 
> >> +@item env
> >> +If provided, this should be an object where each value is a string.
> 
> Eli> This doesn't say what should those string values be.  Shouldn't they
> Eli> be of the format "@var{variable}=@var{value}"?
> 
> In JSON an object is a dictionary; so the keys are strings and the
> values are as well.  That is it looks like {"variable": "value"}

That's okay, but I think we should say something about the structure
of those strings, and {"variable": "value"} goes a long way towards
that.
  

> Date: Tue, 16 May 2023 22:10:54 +0300
> Cc: gdb-patches@sourceware.org
> X-Spam-Status: No, score=1.7 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH,
>  DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF,
>  RCVD_IN_BARRACUDACENTRAL, SPF_HELO_PASS, SPF_PASS, TXREP,
>  T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6
> From: Eli Zaretskii via Gdb-patches <gdb-patches@sourceware.org>
> 
> > From: Tom Tromey <tromey@adacore.com>
> > Cc: Tom Tromey <tromey@adacore.com>,  gdb-patches@sourceware.org
> > Date: Tue, 16 May 2023 13:06:09 -0600
> > 
> > >> +@item env
> > >> +If provided, this should be an object where each value is a string.
> > 
> > Eli> This doesn't say what should those string values be.  Shouldn't they
> > Eli> be of the format "@var{variable}=@var{value}"?
> > 
> > In JSON an object is a dictionary; so the keys are strings and the
> > values are as well.  That is it looks like {"variable": "value"}
> 
> That's okay, but I think we should say something about the structure
> of those strings, and {"variable": "value"} goes a long way towards
           ^^^^^^^
That should have been "objects", sorry.

> that.