patch-sigpipe-global

Index: doc/src/sgml/libpq.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql-server/doc/src/sgml/libpq.sgml,v
retrieving revision 1.141
diff -c -r1.141 libpq.sgml
*** doc/src/sgml/libpq.sgml	1 Nov 2003 01:56:29 -0000	1.141
--- doc/src/sgml/libpq.sgml	3 Nov 2003 20:35:57 -0000
***************
*** 645,650 ****
--- 645,693 ----
    </listitem>
   </varlistentry>
  
+  <varlistentry>
+   <term><function>PQsetsighandling</function><indexterm><primary>PQsetsighandling</></></term>
+   <term><function>PQgetsighandling</function><indexterm><primary>PQgetsighandling</></></term>
+   <listitem>
+    <para>
+    Set/query SIGPIPE signal handling.
+ <synopsis>
+ void PQsetsighandling(int internal_sigign);
+ </synopsis>
+ <synopsis>
+ int PQgetsighandling(void);
+ </synopsis>
+ </para>
+ 
+ <para>
+     These functions allow to query and set the SIGPIPE signal handling
+     of libpq: by default, Unix systems generate a (fatal) SIGPIPE signal
+     on a send to a socket that lost it's connection. Most callers expect
+     a normal error return instead of the signal. A normal error return
+     can be achieved by blocking or ignoring the SIGPIPE signal. This can
+     be done either globally in the application or inside libpq.
+    </para>
+    <para>
+     If internal signal handling is enabled (this is the default), then
+     libpq sets the SIGPIPE handler to SIG_IGN before every socket send
+     operation and restores it afterwards. This prevents libpq from
+     killing the application, at the cost of a slight performance
+     decrease. This approach is not reliable for multithreaded applications.
+    </para>
+    <para>
+     If internal signal handling is disabled, then the caller is
+     responsible for blocking or handling SIGPIPE signals. This is
+     recommended for multithreaded applications.
+    </para>
+    <para>
+     The signal handler setting is a global flag, it affects all
+     connections. The setting has no effect for Win32 clients - Win32
+     doesn't generate SIGPIPE events.
+    </para>
+   </listitem>
+  </varlistentry>
+ 
+ 
   </variablelist>
  </para>
  </sect1>
Index: src/interfaces/libpq/blibpqdll.def
===================================================================
RCS file: /projects/cvsroot/pgsql-server/src/interfaces/libpq/blibpqdll.def,v
retrieving revision 1.9
diff -c -r1.9 blibpqdll.def
*** src/interfaces/libpq/blibpqdll.def	13 Aug 2003 16:29:03 -0000	1.9
--- src/interfaces/libpq/blibpqdll.def	3 Nov 2003 20:35:59 -0000
***************
*** 113,118 ****
--- 113,120 ----
      _PQfformat               @ 109
      _PQexecPrepared          @ 110
      _PQsendQueryPrepared     @ 111
+     _PQsetsighandling        @ 112
+     _PQgetsighandling        @ 113
  
  ; Aliases for MS compatible names
      PQconnectdb             = _PQconnectdb            
***************
*** 226,228 ****
--- 228,232 ----
      PQfformat               = _PQfformat
      PQexecPrepared          = _PQexecPrepared
      PQsendQueryPrepared     = _PQsendQueryPrepared
+     PQsetsighandling        = _PQsetsighandling
+     PQgetsighandling        = _PQgetsighandling
Index: src/interfaces/libpq/fe-secure.c
===================================================================
RCS file: /projects/cvsroot/pgsql-server/src/interfaces/libpq/fe-secure.c,v
retrieving revision 1.32
diff -c -r1.32 fe-secure.c
*** src/interfaces/libpq/fe-secure.c	29 Sep 2003 16:38:04 -0000	1.32
--- src/interfaces/libpq/fe-secure.c	3 Nov 2003 20:35:59 -0000
***************
*** 198,203 ****
--- 198,204 ----
  -----END DH PARAMETERS-----\n";
  #endif
  
+ static int do_sigaction = 1;
  /* ------------------------------------------------------------ */
  /*			 Procedures common to all secure sessions			*/
  /* ------------------------------------------------------------ */
***************
*** 348,354 ****
  	ssize_t		n;
  
  #ifndef WIN32
! 	pqsigfunc	oldsighandler = pqsignal(SIGPIPE, SIG_IGN);
  #endif
  
  #ifdef USE_SSL
--- 349,358 ----
  	ssize_t		n;
  
  #ifndef WIN32
! 	pqsigfunc	oldsighandler = NULL;
! 
! 	if (do_sigaction)
! 		oldsighandler = pqsignal(SIGPIPE, SIG_IGN);
  #endif
  
  #ifdef USE_SSL
***************
*** 408,417 ****
  		n = send(conn->sock, ptr, len, 0);
  
  #ifndef WIN32
! 	pqsignal(SIGPIPE, oldsighandler);
  #endif
  
  	return n;
  }
  
  /* ------------------------------------------------------------ */
--- 412,432 ----
  		n = send(conn->sock, ptr, len, 0);
  
  #ifndef WIN32
! 	if (do_sigaction)
! 		pqsignal(SIGPIPE, oldsighandler);
  #endif
  
  	return n;
+ }
+ 
+ void PQsetsighandling(int internal_sigign)
+ {
+ 	do_sigaction = internal_sigign;
+ }
+ 
+ int PQgetsighandling(void)
+ {
+ 	return do_sigaction;
  }
  
  /* ------------------------------------------------------------ */
Index: src/interfaces/libpq/libpq-fe.h
===================================================================
RCS file: /projects/cvsroot/pgsql-server/src/interfaces/libpq/libpq-fe.h,v
retrieving revision 1.100
diff -c -r1.100 libpq-fe.h
*** src/interfaces/libpq/libpq-fe.h	27 Aug 2003 00:33:34 -0000	1.100
--- src/interfaces/libpq/libpq-fe.h	3 Nov 2003 20:36:00 -0000
***************
*** 221,226 ****
--- 221,232 ----
  /* free the data structure returned by PQconndefaults() */
  extern void PQconninfoFree(PQconninfoOption *connOptions);
  
+ /* ===	in fe-secure.c === */
+ 
+ /* get/set SIGPIPE handling */
+ extern void PQsetsighandling(int internal_sigign);
+ extern int PQgetsighandling(void);
+ 
  /*
   * close the current connection and restablish a new one with the same
   * parameters