Merging r3933, r4154:

A new fix for the case when ssl_session_cache defined, but ssl is not
enabled in any server. The previous r1033 does not help when unused zone
becomes used after reconfiguration, so it is backed out.

The initial thought was to make SSL modules independed from SSL implementation
and to keep OpenSSL code dependance as much as in separate files.

src/core/ngx_cycle.c

@@ -418,11 +418,6 @@ ngx_init_cycle(ngx_cycle_t *old_cycle)
             goto failed;
         }
 
-        if (shm_zone[i].init == NULL) {
-            /* unused shared zone */
-            continue;
-        }
-
         shm_zone[i].shm.log = cycle->log;
 
         opart = &old_cycle->shared_memory.part;

src/event/ngx_event_openssl.c

@@ -26,8 +26,7 @@ static void ngx_ssl_connection_error(ngx_connection_t *c, int sslerr,
     ngx_err_t err, char *text);
 static void ngx_ssl_clear_error(ngx_log_t *log);
 
-static ngx_int_t ngx_ssl_session_cache_init(ngx_shm_zone_t *shm_zone,
-    void *data);
+ngx_int_t ngx_ssl_session_cache_init(ngx_shm_zone_t *shm_zone, void *data);
 static int ngx_ssl_new_session(ngx_ssl_conn_t *ssl_conn,
     ngx_ssl_session_t *sess);
 static ngx_ssl_session_t *ngx_ssl_get_cached_session(ngx_ssl_conn_t *ssl_conn,
@@ -1505,8 +1504,6 @@ ngx_ssl_session_cache(ngx_ssl_t *ssl, ngx_str_t *sess_ctx,
     SSL_CTX_set_timeout(ssl->ctx, (long) timeout);
 
     if (shm_zone) {
-        shm_zone->init = ngx_ssl_session_cache_init;
-
         SSL_CTX_sess_set_new_cb(ssl->ctx, ngx_ssl_new_session);
         SSL_CTX_sess_set_get_cb(ssl->ctx, ngx_ssl_get_cached_session);
         SSL_CTX_sess_set_remove_cb(ssl->ctx, ngx_ssl_remove_session);
@@ -1524,7 +1521,7 @@ ngx_ssl_session_cache(ngx_ssl_t *ssl, ngx_str_t *sess_ctx,
 }
 
 
-static ngx_int_t
+ngx_int_t
 ngx_ssl_session_cache_init(ngx_shm_zone_t *shm_zone, void *data)
 {
     size_t                    len;

src/event/ngx_event_openssl.h

@@ -104,6 +104,7 @@ ngx_int_t ngx_ssl_dhparam(ngx_conf_t *cf, ngx_ssl_t *ssl, ngx_str_t *file);
 ngx_int_t ngx_ssl_ecdh_curve(ngx_conf_t *cf, ngx_ssl_t *ssl, ngx_str_t *name);
 ngx_int_t ngx_ssl_session_cache(ngx_ssl_t *ssl, ngx_str_t *sess_ctx,
     ssize_t builtin_session_cache, ngx_shm_zone_t *shm_zone, time_t timeout);
+ngx_int_t ngx_ssl_session_cache_init(ngx_shm_zone_t *shm_zone, void *data);
 ngx_int_t ngx_ssl_create_connection(ngx_ssl_t *ssl, ngx_connection_t *c,
     ngx_uint_t flags);
 

src/http/modules/ngx_http_ssl_module.c

@@ -616,6 +616,8 @@ ngx_http_ssl_session_cache(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
                 return NGX_CONF_ERROR;
             }
 
+            sscf->shm_zone->init = ngx_ssl_session_cache_init;
+
             continue;
         }
 

src/mail/ngx_mail_ssl_module.c

@@ -464,6 +464,8 @@ ngx_mail_ssl_session_cache(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
                 return NGX_CONF_ERROR;
             }
 
+            scf->shm_zone->init = ngx_ssl_session_cache_init;
+
             continue;
         }