Line data    Source code

       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * pgstrsignal.c
       4             :  *    Identify a Unix signal number
       5             :  *
       6             :  * On platforms compliant with modern POSIX, this just wraps strsignal(3).
       7             :  * Elsewhere, we do the best we can.
       8             :  *
       9             :  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
      10             :  * Portions Copyright (c) 1994, Regents of the University of California
      11             :  *
      12             :  * IDENTIFICATION
      13             :  *    src/port/pgstrsignal.c
      14             :  *
      15             :  *-------------------------------------------------------------------------
      16             :  */
      17             : 
      18             : #include "c.h"
      19             : 
      20             : 
      21             : /*
      22             :  * pg_strsignal
      23             :  *
      24             :  * Return a string identifying the given Unix signal number.
      25             :  *
      26             :  * The result is declared "const char *" because callers should not
      27             :  * modify the string.  Note, however, that POSIX does not promise that
      28             :  * the string will remain valid across later calls to strsignal().
      29             :  *
      30             :  * This version guarantees to return a non-NULL pointer, although
      31             :  * some platforms' versions of strsignal() reputedly do not.
      32             :  *
      33             :  * Note that the fallback cases just return constant strings such as
      34             :  * "unrecognized signal".  Project style is for callers to print the
      35             :  * numeric signal value along with the result of this function, so
      36             :  * there's no need to work harder than that.
      37             :  */
      38             : const char *
      39           6 : pg_strsignal(int signum)
      40             : {
      41             :     const char *result;
      42             : 
      43             :     /*
      44             :      * If we have strsignal(3), use that --- but check its result for NULL.
      45             :      */
      46             : #ifdef HAVE_STRSIGNAL
      47           6 :     result = strsignal(signum);
      48           6 :     if (result == NULL)
      49           0 :         result = "unrecognized signal";
      50             : #else
      51             : 
      52             :     /*
      53             :      * We used to have code here to try to use sys_siglist[] if available.
      54             :      * However, it seems that all platforms with sys_siglist[] have also had
      55             :      * strsignal() for many years now, so that was just a waste of code.
      56             :      */
      57             :     result = "(signal names not available on this platform)";
      58             : #endif
      59             : 
      60           6 :     return result;
      61             : }