TLA  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) 1996-2023, 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.
      39                 :  */
      40                 : void
      41 CBC        1857 : pqinitmask(void)
      42                 : {
      43            1857 :     sigemptyset(&UnBlockSig);
      44                 : 
      45                 :     /* Note: InitializeLatchSupport() modifies UnBlockSig. */
      46                 : 
      47                 :     /* First set all signals, then clear some. */
      48            1857 :     sigfillset(&BlockSig);
      49            1857 :     sigfillset(&StartupBlockSig);
      50                 : 
      51                 :     /*
      52                 :      * Unmark those signals that should never be blocked. Some of these signal
      53                 :      * names don't exist on all platforms.  Most do, but might as well ifdef
      54                 :      * them all for consistency...
      55                 :      */
      56                 : #ifdef SIGTRAP
      57            1857 :     sigdelset(&BlockSig, SIGTRAP);
      58            1857 :     sigdelset(&StartupBlockSig, SIGTRAP);
      59                 : #endif
      60                 : #ifdef SIGABRT
      61            1857 :     sigdelset(&BlockSig, SIGABRT);
      62            1857 :     sigdelset(&StartupBlockSig, SIGABRT);
      63                 : #endif
      64                 : #ifdef SIGILL
      65            1857 :     sigdelset(&BlockSig, SIGILL);
      66            1857 :     sigdelset(&StartupBlockSig, SIGILL);
      67                 : #endif
      68                 : #ifdef SIGFPE
      69            1857 :     sigdelset(&BlockSig, SIGFPE);
      70            1857 :     sigdelset(&StartupBlockSig, SIGFPE);
      71                 : #endif
      72                 : #ifdef SIGSEGV
      73            1857 :     sigdelset(&BlockSig, SIGSEGV);
      74            1857 :     sigdelset(&StartupBlockSig, SIGSEGV);
      75                 : #endif
      76                 : #ifdef SIGBUS
      77            1857 :     sigdelset(&BlockSig, SIGBUS);
      78            1857 :     sigdelset(&StartupBlockSig, SIGBUS);
      79                 : #endif
      80                 : #ifdef SIGSYS
      81            1857 :     sigdelset(&BlockSig, SIGSYS);
      82            1857 :     sigdelset(&StartupBlockSig, SIGSYS);
      83                 : #endif
      84                 : #ifdef SIGCONT
      85            1857 :     sigdelset(&BlockSig, SIGCONT);
      86            1857 :     sigdelset(&StartupBlockSig, SIGCONT);
      87                 : #endif
      88                 : 
      89                 : /* Signals unique to startup */
      90                 : #ifdef SIGQUIT
      91            1857 :     sigdelset(&StartupBlockSig, SIGQUIT);
      92                 : #endif
      93                 : #ifdef SIGTERM
      94            1857 :     sigdelset(&StartupBlockSig, SIGTERM);
      95                 : #endif
      96                 : #ifdef SIGALRM
      97            1857 :     sigdelset(&StartupBlockSig, SIGALRM);
      98                 : #endif
      99            1857 : }