Re: [Qemu-devel] [PATCH 1/5] linux-user: remove hardcoded value of _NSIG in signal.c

[Aurelien Jarno <aurelien@aurel32.net>]

Stefan Weil a écrit :
> Aurelien Jarno schrieb:
>> From: Arnaud Patard <arnaud.patard@rtp-net.org>
>>
>> In a bunch of places, 64 is used as value of _NSIG but it's wrong
>> at least on MIPS were _NSIG is 128.
>>
>> Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
>> Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
>> ---
>>  linux-user/signal.c |   12 ++++++------
>>  1 files changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/linux-user/signal.c b/linux-user/signal.c
>> index 2df17aa..6620ce3 100644
>> --- a/linux-user/signal.c
>> +++ b/linux-user/signal.c
>> @@ -44,7 +44,7 @@ static struct target_sigaction sigact_table[TARGET_NSIG];
>>  static void host_signal_handler(int host_signum, siginfo_t *info,
>>                                  void *puc);
>>  
>> -static uint8_t host_to_target_signal_table[65] = {
>> +static uint8_t host_to_target_signal_table[_NSIG+1] = {
>>      [SIGHUP] = TARGET_SIGHUP,
>>      [SIGINT] = TARGET_SIGINT,
>>      [SIGQUIT] = TARGET_SIGQUIT,
>> @@ -87,7 +87,7 @@ static uint8_t host_to_target_signal_table[65] = {
>>      [__SIGRTMIN] = __SIGRTMAX,
>>      [__SIGRTMAX] = __SIGRTMIN,
>>  };
>> -static uint8_t target_to_host_signal_table[65];
>> +static uint8_t target_to_host_signal_table[_NSIG+1];
>>  
>>  static inline int on_sig_stack(unsigned long sp)
>>  {
>> @@ -103,14 +103,14 @@ static inline int sas_ss_flags(unsigned long sp)
>>  
>>  int host_to_target_signal(int sig)
>>  {
>> -    if (sig > 64)
>> +    if (sig > _NSIG)
>>          return sig;
>>      return host_to_target_signal_table[sig];
>>  }
>>  
>>  int target_to_host_signal(int sig)
>>  {
>> -    if (sig > 64)
>> +    if (sig > _NSIG)
>>          return sig;
>>      return target_to_host_signal_table[sig];
>>  }
>> @@ -311,11 +311,11 @@ void signal_init(void)
>>      int host_sig;
>>  
>>      /* generate signal conversion tables */
>> -    for(i = 1; i <= 64; i++) {
>> +    for(i = 1; i <= _NSIG; i++) {
>>          if (host_to_target_signal_table[i] == 0)
>>              host_to_target_signal_table[i] = i;
>>      }
>> -    for(i = 1; i <= 64; i++) {
>> +    for(i = 1; i <= _NSIG; i++) {
>>          j = host_to_target_signal_table[i];
>>          target_to_host_signal_table[j] = i;
>>      }
>>   
> 
> At least in my linux installation, _NSIG is 65 (x86) or 128 (mips),
> so the patch above should replace 64 by (_NSIG - 1) and 65 by _NSIG.
> 
> But perhaps it does no harm if the code allocates an unused signal
> at the end.
> 
> For my tests with mips host and tci, I used
> static uint8_t target_to_host_signal_table[_NSIG]
> 

>From /usr/include/bits/signum.h:
#define   _NSIG           65      /* Biggest signal number + 1

I confirm that all use of _NSIG of them should be decremented by one.

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net