Re: [PATCH] testsuite: expect possible pagination when starting gdb

[Simon Marchi <simon dot marchi at ericsson dot com>]

On 2014-10-20 01:46 PM, Simon Marchi wrote:
> On 2014-09-26 05:01 PM, Simon Marchi wrote:
>> When gdb starts, the lines that appear before the first prompt may get
>> paginated if the terminal in which the tests are ran is too small (in
>> terms of rows). These lines include the welcome/license message and
>> possibly more, such as "Reading symbols from...". Pagination is disabled
>> right after gdb is started (with "set height 0"), but this output happens
>> before we are able to set height.
>>
>> If these lines get paginated, gdb waits for the user to press enter and
>> the test harness waits for gdb to print its prompt, resulting in a
>> deadlock.
>>
>> My first idea was to launch gdb with --quiet. However, some lines are
>> still printed ("Reading symbols from...", some more stuff when attaching
>> with --pid, etc).
>>
>> The proposed solution simply expects that pagination can occur after
>> starting gdb. If this is the case, it sends a "\n" and loops.
>>
>> gdb/testsuite/Changelog:
>>
>> 	* lib/gdb.exp (default_gdb_start): After starting gdb, loop
>> 	as long as we get pagination notifications.
>> ---
>>  gdb/testsuite/lib/gdb.exp | 39 ++++++++++++++++++++++++---------------
>>  1 file changed, 24 insertions(+), 15 deletions(-)
>>
>> diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
>> index 47dc27b..820f87f 100644
>> --- a/gdb/testsuite/lib/gdb.exp
>> +++ b/gdb/testsuite/lib/gdb.exp
>> @@ -1451,7 +1451,7 @@ proc default_gdb_spawn { } {
>>  # Default gdb_start procedure.
>>  
>>  proc default_gdb_start { } {
>> -    global gdb_prompt
>> +    global gdb_prompt pagination_prompt
>>      global gdb_spawn_id
>>  
>>      if [info exists gdb_spawn_id] {
>> @@ -1466,20 +1466,29 @@ proc default_gdb_start { } {
>>      # When running over NFS, particularly if running many simultaneous
>>      # tests on different hosts all using the same server, things can
>>      # get really slow.  Give gdb at least 3 minutes to start up.
>> -    gdb_expect 360 {
>> -	-re "\[\r\n\]$gdb_prompt $" {
>> -	    verbose "GDB initialized."
>> -	}
>> -	-re "$gdb_prompt $"	{
>> -	    perror "GDB never initialized."
>> -	    unset gdb_spawn_id
>> -	    return -1
>> -	}
>> -	timeout	{
>> -	    perror "(timeout) GDB never initialized after 10 seconds."
>> -	    remote_close host
>> -	    unset gdb_spawn_id
>> -	    return -1
>> +    set loop_again 1
>> +    while { $loop_again } {
>> +	set loop_again 0
>> +	gdb_expect 360 {
>> +	    -re "$pagination_prompt" {
>> +		verbose "Hit pagination during startup. Pressing enter to continue."
>> +		send_gdb "\n"
>> +		set loop_again 1
>> +	    }
>> +	    -re "\[\r\n\]$gdb_prompt $" {
>> +		verbose "GDB initialized."
>> +	    }
>> +	    -re "$gdb_prompt $"	{
>> +		perror "GDB never initialized."
>> +		unset gdb_spawn_id
>> +		return -1
>> +	    }
>> +	    timeout	{
>> +		perror "(timeout) GDB never initialized after 10 seconds."
>> +		remote_close host
>> +		unset gdb_spawn_id
>> +		return -1
>> +	    }
>>  	}
>>      }
>>  
>>
> 
> Ping.

Ping.