Line data    Source code

       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * pqsignal.c
       4             :  *    Backend signal(2) support (see also src/port/pqsignal.c)
       5             :  *
       6             :  * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
       7             :  * Portions Copyright (c) 1994, Regents of the University of California
       8             :  *
       9             :  *
      10             :  * IDENTIFICATION
      11             :  *    src/backend/libpq/pqsignal.c
      12             :  *
      13             :  * ------------------------------------------------------------------------
      14             :  */
      15             : 
      16             : #include "postgres.h"
      17             : 
      18             : #include "libpq/pqsignal.h"
      19             : 
      20             : 
      21             : /* Global variables */
      22             : sigset_t    UnBlockSig,
      23             :             BlockSig,
      24             :             StartupBlockSig;
      25             : 
      26             : 
      27             : /*
      28             :  * Initialize BlockSig, UnBlockSig, and StartupBlockSig.
      29             :  *
      30             :  * BlockSig is the set of signals to block when we are trying to block
      31             :  * signals.  This includes all signals we normally expect to get, but NOT
      32             :  * signals that should never be turned off.
      33             :  *
      34             :  * StartupBlockSig is the set of signals to block during startup packet
      35             :  * collection; it's essentially BlockSig minus SIGTERM, SIGQUIT, SIGALRM.
      36             :  *
      37             :  * UnBlockSig is the set of signals to block when we don't want to block
      38             :  * signals (is this ever nonzero??)
      39             :  */
      40             : void
      41        7504 : pqinitmask(void)
      42             : {
      43        7504 :     sigemptyset(&UnBlockSig);
      44             : 
      45             :     /* First set all signals, then clear some. */
      46        7504 :     sigfillset(&BlockSig);
      47        7504 :     sigfillset(&StartupBlockSig);
      48             : 
      49             :     /*
      50             :      * Unmark those signals that should never be blocked. Some of these signal
      51             :      * names don't exist on all platforms.  Most do, but might as well ifdef
      52             :      * them all for consistency...
      53             :      */
      54             : #ifdef SIGTRAP
      55        7504 :     sigdelset(&BlockSig, SIGTRAP);
      56        7504 :     sigdelset(&StartupBlockSig, SIGTRAP);
      57             : #endif
      58             : #ifdef SIGABRT
      59        7504 :     sigdelset(&BlockSig, SIGABRT);
      60        7504 :     sigdelset(&StartupBlockSig, SIGABRT);
      61             : #endif
      62             : #ifdef SIGILL
      63        7504 :     sigdelset(&BlockSig, SIGILL);
      64        7504 :     sigdelset(&StartupBlockSig, SIGILL);
      65             : #endif
      66             : #ifdef SIGFPE
      67        7504 :     sigdelset(&BlockSig, SIGFPE);
      68        7504 :     sigdelset(&StartupBlockSig, SIGFPE);
      69             : #endif
      70             : #ifdef SIGSEGV
      71        7504 :     sigdelset(&BlockSig, SIGSEGV);
      72        7504 :     sigdelset(&StartupBlockSig, SIGSEGV);
      73             : #endif
      74             : #ifdef SIGBUS
      75        7504 :     sigdelset(&BlockSig, SIGBUS);
      76        7504 :     sigdelset(&StartupBlockSig, SIGBUS);
      77             : #endif
      78             : #ifdef SIGSYS
      79        7504 :     sigdelset(&BlockSig, SIGSYS);
      80        7504 :     sigdelset(&StartupBlockSig, SIGSYS);
      81             : #endif
      82             : #ifdef SIGCONT
      83        7504 :     sigdelset(&BlockSig, SIGCONT);
      84        7504 :     sigdelset(&StartupBlockSig, SIGCONT);
      85             : #endif
      86             : 
      87             : /* Signals unique to startup */
      88             : #ifdef SIGQUIT
      89        7504 :     sigdelset(&StartupBlockSig, SIGQUIT);
      90             : #endif
      91             : #ifdef SIGTERM
      92        7504 :     sigdelset(&StartupBlockSig, SIGTERM);
      93             : #endif
      94             : #ifdef SIGALRM
      95        7504 :     sigdelset(&StartupBlockSig, SIGALRM);
      96             : #endif
      97        7504 : }