Better document PQinitSSL(0) behavior in regards to libcrypto.

Author: bmomjian

doc/src/sgml/libpq.sgml

@@ -1,4 +1,4 @@
-<!-- $PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.279 2009/03/23 01:45:29 momjian Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/libpq.sgml,v 1.280 2009/03/28 01:36:11 momjian Exp $ -->
 
 <chapter id="libpq">
  <title><application>libpq</application> - C Library</title>
@@ -6169,11 +6169,13 @@ myEventProc(PGEventId evtId, void *evtInfo, void *passThrough)
   </para>
 
   <para>
-   If you are using <acronym>SSL</> inside your application (in addition
-   to inside <application>libpq</application>), you can call
-   <function>PQinitSSL(int)</> with <literal>0</> to tell
-   <application>libpq</application> that the <acronym>SSL</> library
-   has already been initialized by your application.
+   If your application initializes <literal>libssl</> or
+   <literal>libcrypto</> libraries and <application>libpq</application>
+   is built with <acronym>SSL</> support, you should call
+   <function>PQinitSSL(0)</> to tell <application>libpq</application>
+   that the <literal>libssl</> and <literal>libcrypto</> libraries
+   have been initialized by your application so
+   <application>libpq</application> will not initialize those libraries.
    <!-- If this URL changes replace it with a URL to www.archive.org. -->
    See <ulink
    url="http://h71000.www7.hp.com/doc/83final/BA554_90007/ch04.html"></ulink>

src/interfaces/libpq/fe-secure.c

@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.119 2009/01/28 15:06:47 mha Exp $
+ *	  $PostgreSQL: pgsql/src/interfaces/libpq/fe-secure.c,v 1.120 2009/03/28 01:36:11 momjian Exp $
  *
  * NOTES
  *
@@ -870,6 +870,7 @@ init_ssl_system(PGconn *conn)
 
 		if (ssl_open_connections++ == 0)
 		{
+			/* This is actually libcrypto, not libssl. */
 			/* These are only required for threaded SSL applications */
 			CRYPTO_set_id_callback(pq_threadidcallback);
 			CRYPTO_set_locking_callback(pq_lockingcallback);
@@ -934,6 +935,7 @@ destroy_ssl_system(void)
 
 		if (ssl_open_connections == 0)
 		{
+			/* This is actually libcrypto, not libssl. */
 			/* No connections left, unregister all callbacks */
 			CRYPTO_set_locking_callback(NULL);
 			CRYPTO_set_id_callback(NULL);