-/* $Id: connection.c,v 1.10 2007-08-14 14:03:02 adam Exp $
- Copyright (c) 2006-2007, Index Data.
-
-This file is part of Pazpar2.
+/* This file is part of Pazpar2.
+ Copyright (C) 2006-2010 Index Data
Pazpar2 is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
for more details.
You should have received a copy of the GNU General Public License
-along with Pazpar2; see the file LICENSE. If not, write to the
-Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA.
- */
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+*/
/** \file connection.c
\brief Z39.50 connection (low-level client)
*/
+#if HAVE_CONFIG_H
+#include <config.h>
+#endif
+
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
+#if HAVE_SYS_TIME_H
#include <sys/time.h>
+#endif
+#if HAVE_UNISTD_H
#include <unistd.h>
-#include <sys/socket.h>
-#include <netdb.h>
+#endif
+
#include <signal.h>
-#include <ctype.h>
#include <assert.h>
-#if HAVE_CONFIG_H
-#include "cconfig.h"
-#endif
-
#include <yaz/log.h>
#include <yaz/comstack.h>
#include <yaz/tcpip.h>
#include "connection.h"
-#include "eventl.h"
-#include "pazpar2.h"
+#include "session.h"
#include "host.h"
#include "client.h"
#include "settings.h"
-#include "parameters.h"
+
+/* connection counting (1) , disable connection counting (0) */
+#if 0
+static YAZ_MUTEX g_mutex = 0;
+static int no_connections = 0;
+
+static void connection_use(int delta)
+{
+ if (!g_mutex)
+ yaz_mutex_create(&g_mutex);
+ yaz_mutex_enter(g_mutex);
+ no_connections += delta;
+ yaz_mutex_leave(g_mutex);
+ yaz_log(YLOG_LOG, "%s connections=%d", delta > 0 ? "INC" : "DEC",
+ no_connections);
+}
+#else
+#define connection_use(x)
+#endif
/** \brief Represents a physical, reusable connection to a remote Z39.50 host
*/
struct connection {
IOCHAN iochan;
- COMSTACK link;
+ ZOOM_connection link;
struct host *host;
struct client *client;
- char *ibuf;
- int ibufsize;
- char *authentication; // Empty string or authentication string if set
char *zproxy;
enum {
Conn_Resolving,
Conn_Connecting,
- Conn_Open,
- Conn_Waiting,
+ Conn_Open
} state;
+ int operation_timeout;
+ int session_timeout;
struct connection *next; // next for same host or next in free list
};
-static struct connection *connection_freelist = 0;
+static int connection_connect(struct connection *con, iochan_man_t iochan_man);
+
+static int connection_is_idle(struct connection *co)
+{
+ ZOOM_connection link = co->link;
+ int event;
+
+ if (co->state != Conn_Open || !link)
+ return 0;
+
+ if (!ZOOM_connection_is_idle(link))
+ return 0;
+ event = ZOOM_connection_peek_event(link);
+ if (event == ZOOM_EVENT_NONE)
+ return 1;
+ else
+ return 0;
+}
+
+ZOOM_connection connection_get_link(struct connection *co)
+{
+ return co->link;
+}
static void remove_connection_from_host(struct connection *con)
{
if (*conp == con)
{
*conp = (*conp)->next;
- return;
+ break;
}
conp = &(*conp)->next;
}
- assert(*conp == 0);
+ yaz_cond_broadcast(con->host->cond_ready);
}
// Close connection and recycle structure
-void connection_destroy(struct connection *co)
+static void connection_destroy(struct connection *co)
{
if (co->link)
{
- cs_close(co->link);
+ ZOOM_connection_destroy(co->link);
iochan_destroy(co->iochan);
}
-
yaz_log(YLOG_DEBUG, "Connection destroy %s", co->host->hostport);
- remove_connection_from_host(co);
if (co->client)
{
client_disconnect(co->client);
}
+
+ remove_connection_from_host(co);
xfree(co->zproxy);
- co->zproxy = 0;
- co->next = connection_freelist;
- connection_freelist = co;
+ xfree(co);
+ connection_use(-1);
}
// Creates a new connection for client, associated with the host of
// client's database
-struct connection *connection_create(struct client *cl)
+static struct connection *connection_create(struct client *cl,
+ int operation_timeout,
+ int session_timeout,
+ iochan_man_t iochan_man)
{
- struct connection *new;
+ struct connection *co;
struct host *host = client_get_host(cl);
- if ((new = connection_freelist))
- connection_freelist = new->next;
- else
+ co = xmalloc(sizeof(*co));
+ co->host = host;
+
+ co->client = cl;
+ co->zproxy = 0;
+ client_set_connection(cl, co);
+ co->link = 0;
+ co->state = Conn_Resolving;
+ co->operation_timeout = operation_timeout;
+ co->session_timeout = session_timeout;
+ if (host->ipport)
+ connection_connect(co, iochan_man);
+
+ yaz_mutex_enter(host->mutex);
+ co->next = co->host->connections;
+ co->host->connections = co;
+ yaz_mutex_leave(host->mutex);
+
+ connection_use(1);
+ return co;
+}
+
+static void non_block_events(struct connection *co)
+{
+ int got_records = 0;
+ IOCHAN iochan = co->iochan;
+ ZOOM_connection link = co->link;
+ while (1)
{
- new = xmalloc(sizeof (struct connection));
- new->ibuf = 0;
- new->ibufsize = 0;
+ struct client *cl = co->client;
+ int ev;
+ int r = ZOOM_event_nonblock(1, &link);
+ if (!r)
+ break;
+ if (!cl)
+ continue;
+ ev = ZOOM_connection_last_event(link);
+
+#if 0
+ yaz_log(YLOG_LOG, "%p Connection ZOOM_EVENT_%s", co, ZOOM_get_event_str(ev));
+#endif
+ switch (ev)
+ {
+ case ZOOM_EVENT_END:
+ {
+ const char *error, *addinfo;
+ int err;
+ if ((err = ZOOM_connection_error(link, &error, &addinfo)))
+ {
+ yaz_log(YLOG_LOG, "Error %s from %s",
+ error, client_get_url(cl));
+ client_set_diagnostic(cl, err);
+ client_set_state(cl, Client_Error);
+ }
+ else
+ {
+ iochan_settimeout(iochan, co->session_timeout);
+ client_set_state(cl, Client_Idle);
+ }
+ yaz_cond_broadcast(co->host->cond_ready);
+ }
+ break;
+ case ZOOM_EVENT_SEND_DATA:
+ break;
+ case ZOOM_EVENT_RECV_DATA:
+ break;
+ case ZOOM_EVENT_UNKNOWN:
+ break;
+ case ZOOM_EVENT_SEND_APDU:
+ client_set_state(co->client, Client_Working);
+ iochan_settimeout(iochan, co->operation_timeout);
+ break;
+ case ZOOM_EVENT_RECV_APDU:
+ break;
+ case ZOOM_EVENT_CONNECT:
+ yaz_log(YLOG_LOG, "Connected to %s", client_get_url(cl));
+ co->state = Conn_Open;
+ break;
+ case ZOOM_EVENT_RECV_SEARCH:
+ client_search_response(cl);
+ break;
+ case ZOOM_EVENT_RECV_RECORD:
+ client_record_response(cl);
+ got_records = 1;
+ break;
+ default:
+ yaz_log(YLOG_LOG, "Unhandled event (%d) from %s",
+ ev, client_get_url(cl));
+ }
+ }
+ if (got_records)
+ {
+ struct client *cl = co->client;
+ if (cl)
+ {
+ client_got_records(cl);
+ }
}
- new->host = host;
- new->next = new->host->connections;
- new->host->connections = new;
- new->client = cl;
- new->authentication = "";
- new->zproxy = 0;
- client_set_connection(cl, new);
- new->link = 0;
- new->state = Conn_Resolving;
- if (host->ipport)
- connection_connect(new);
- return new;
}
-static void connection_handler(IOCHAN i, int event)
+void connection_continue(struct connection *co)
{
- struct connection *co = iochan_getdata(i);
- struct client *cl = co->client;
- struct session *se = 0;
+ int r = ZOOM_connection_exec_task(co->link);
+ if (!r)
+ yaz_log(YLOG_WARN, "No task was executed for connection");
+ iochan_setflags(co->iochan, ZOOM_connection_get_mask(co->link));
+ iochan_setfd(co->iochan, ZOOM_connection_get_socket(co->link));
+}
- if (cl)
- se = client_get_session(cl);
- else
+static void connection_handler(IOCHAN iochan, int event)
+{
+ struct connection *co = iochan_getdata(iochan);
+ struct client *cl;
+ struct host *host = co->host;
+
+ yaz_mutex_enter(host->mutex);
+ cl = co->client;
+ if (!cl)
{
+ /* no client associated with it.. We are probably getting
+ a closed connection from the target.. Or, perhaps, an unexpected
+ package.. We will just close the connection */
+ yaz_log(YLOG_LOG, "timeout connection %p event=%d", co, event);
connection_destroy(co);
- return;
+ yaz_mutex_leave(host->mutex);
}
-
- if (event & EVENT_TIMEOUT)
+ else if (event & EVENT_TIMEOUT)
{
if (co->state == Conn_Connecting)
{
yaz_log(YLOG_WARN, "connect timeout %s", client_get_url(cl));
- client_fatal(cl);
+
+ client_set_state(cl, Client_Error);
+ connection_destroy(co);
}
else
{
yaz_log(YLOG_LOG, "idle timeout %s", client_get_url(cl));
connection_destroy(co);
}
- return;
+ yaz_mutex_leave(host->mutex);
}
- if (co->state == Conn_Connecting && event & EVENT_OUTPUT)
- {
- int errcode;
- socklen_t errlen = sizeof(errcode);
-
- if (getsockopt(cs_fileno(co->link), SOL_SOCKET, SO_ERROR, &errcode,
- &errlen) < 0 || errcode != 0)
- {
- client_fatal(cl);
- return;
- }
- else
- {
- yaz_log(YLOG_DEBUG, "Connect OK");
- co->state = Conn_Open;
- if (cl)
- client_set_state(cl, Client_Connected);
- iochan_settimeout(i, global_parameters.z3950_session_timeout);
- }
- }
-
- else if (event & EVENT_INPUT)
+ else
{
- int len = cs_get(co->link, &co->ibuf, &co->ibufsize);
-
- if (len < 0)
- {
- yaz_log(YLOG_WARN|YLOG_ERRNO, "Error reading from %s",
- client_get_url(cl));
- connection_destroy(co);
- return;
- }
- else if (len == 0)
- {
- yaz_log(YLOG_WARN, "EOF reading from %s", client_get_url(cl));
- connection_destroy(co);
- return;
- }
- else if (len > 1) // We discard input if we have no connection
- {
- co->state = Conn_Open;
+ yaz_mutex_leave(host->mutex);
- if (client_is_our_response(cl))
- {
- Z_APDU *a;
- struct session_database *sdb = client_get_database(cl);
- const char *apdulog = session_setting_oneval(sdb, PZ_APDULOG);
+ client_lock(cl);
+ non_block_events(co);
- odr_reset(global_parameters.odr_in);
- odr_setbuf(global_parameters.odr_in, co->ibuf, len, 0);
- if (!z_APDU(global_parameters.odr_in, &a, 0, 0))
- {
- client_fatal(cl);
- return;
- }
+ ZOOM_connection_fire_event_socket(co->link, event);
+
+ non_block_events(co);
+ client_unlock(cl);
- if (apdulog && *apdulog && *apdulog != '0')
- {
- ODR p = odr_createmem(ODR_PRINT);
- yaz_log(YLOG_LOG, "recv APDU %s", client_get_url(cl));
-
- odr_setprint(p, yaz_log_file());
- z_APDU(p, &a, 0, 0);
- odr_setprint(p, stderr);
- odr_destroy(p);
- }
- switch (a->which)
- {
- case Z_APDU_initResponse:
- client_init_response(cl, a);
- break;
- case Z_APDU_searchResponse:
- client_search_response(cl, a);
- break;
- case Z_APDU_presentResponse:
- client_present_response(cl, a);
- break;
- case Z_APDU_close:
- client_close_response(cl, a);
- break;
- default:
- yaz_log(YLOG_WARN,
- "Unexpected Z39.50 response from %s",
- client_get_url(cl));
- client_fatal(cl);
- return;
- }
- // We aren't expecting staggered output from target
- // if (cs_more(t->link))
- // iochan_setevent(i, EVENT_INPUT);
- }
- else // we throw away response and go to idle mode
- {
- yaz_log(YLOG_DEBUG, "Ignoring result of expired operation");
- client_set_state(cl, Client_Idle);
- }
- }
- /* if len==1 we do nothing but wait for more input */
+ if (co->link)
+ {
+ iochan_setflags(iochan, ZOOM_connection_get_mask(co->link));
+ iochan_setfd(iochan, ZOOM_connection_get_socket(co->link));
+ }
}
- client_continue(cl);
}
+
// Disassociate connection from client
-void connection_release(struct connection *co)
+static void connection_release(struct connection *co)
{
struct client *cl = co->client;
- yaz_log(YLOG_DEBUG, "Connection release %s", co->host->hostport);
if (!cl)
return;
client_set_connection(cl, 0);
co->client = 0;
}
-void connect_resolver_host(struct host *host)
+void connect_resolver_host(struct host *host, iochan_man_t iochan_man)
{
- struct connection *con = host->connections;
+ struct connection *con;
+
+start:
+ yaz_mutex_enter(host->mutex);
+ con = host->connections;
while (con)
{
if (con->state == Conn_Resolving)
{
if (!host->ipport) /* unresolved */
{
+ yaz_mutex_leave(host->mutex);
connection_destroy(con);
+ goto start;
/* start all over .. at some point it will be NULL */
- con = host->connections;
- continue;
}
else if (!con->client)
{
+ yaz_mutex_leave(host->mutex);
connection_destroy(con);
/* start all over .. at some point it will be NULL */
- con = host->connections;
- continue;
+ goto start;
}
else
{
- connection_connect(con);
+ yaz_mutex_leave(host->mutex);
+ connection_connect(con, iochan_man);
+ client_start_search(con->client);
+ goto start;
}
}
else
{
yaz_log(YLOG_LOG, "connect_resolver_host: state=%d", con->state);
+ con = con->next;
}
- con = con->next;
- }
-}
-
-int connection_send_apdu(struct connection *co, Z_APDU *a)
-{
- char *buf;
- int len, r;
-
- if (!z_APDU(global_parameters.odr_out, &a, 0, 0))
- {
- odr_perror(global_parameters.odr_out, "Encoding APDU");
- abort();
- }
- buf = odr_getbuf(global_parameters.odr_out, &len, 0);
- r = cs_put(co->link, buf, len);
- if (r < 0)
- {
- yaz_log(YLOG_WARN, "cs_put: %s", cs_errmsg(cs_errno(co->link)));
- return -1;
}
- else if (r == 1)
- {
- fprintf(stderr, "cs_put incomplete (ParaZ does not handle that)\n");
- exit(1);
- }
- odr_reset(global_parameters.odr_out); /* release the APDU structure */
- co->state = Conn_Waiting;
- iochan_setflags(co->iochan, EVENT_INPUT);
- return 0;
+ yaz_mutex_leave(host->mutex);
}
-struct host *connection_get_host(struct connection *con)
+static struct host *connection_get_host(struct connection *con)
{
return con->host;
}
-int connection_connect(struct connection *con)
+static int connection_connect(struct connection *con, iochan_man_t iochan_man)
{
- COMSTACK link = 0;
+ ZOOM_connection link = 0;
struct host *host = connection_get_host(con);
- void *addr;
- int res;
+ ZOOM_options zoptions = ZOOM_options_create();
+ const char *auth;
+ const char *charset;
+ const char *sru;
+ const char *sru_version = 0;
struct session_database *sdb = client_get_database(con->client);
- char *zproxy = session_setting_oneval(sdb, PZ_ZPROXY);
+ const char *zproxy = session_setting_oneval(sdb, PZ_ZPROXY);
+ const char *apdulog = session_setting_oneval(sdb, PZ_APDULOG);
assert(host->ipport);
assert(con);
- if (!(link = cs_create(tcpip_type, 0, PROTO_Z3950)))
+ ZOOM_options_set(zoptions, "async", "1");
+ ZOOM_options_set(zoptions, "implementationName", PACKAGE_NAME);
+ ZOOM_options_set(zoptions, "implementationVersion", VERSION);
+
+ if ((charset = session_setting_oneval(sdb, PZ_NEGOTIATION_CHARSET)))
+ ZOOM_options_set(zoptions, "charset", charset);
+
+ if (zproxy && *zproxy)
{
- yaz_log(YLOG_FATAL|YLOG_ERRNO, "Failed to create comstack");
+ con->zproxy = xstrdup(zproxy);
+ ZOOM_options_set(zoptions, "proxy", zproxy);
+ }
+ if (apdulog && *apdulog)
+ ZOOM_options_set(zoptions, "apdulog", apdulog);
+
+ if ((auth = session_setting_oneval(sdb, PZ_AUTHENTICATION)))
+ ZOOM_options_set(zoptions, "user", auth);
+ if ((sru = session_setting_oneval(sdb, PZ_SRU)) && *sru)
+ ZOOM_options_set(zoptions, "sru", sru);
+ if ((sru_version = session_setting_oneval(sdb, PZ_SRU_VERSION))
+ && *sru_version)
+ ZOOM_options_set(zoptions, "sru_version", sru_version);
+
+ if (!(link = ZOOM_connection_create(zoptions)))
+ {
+ yaz_log(YLOG_FATAL|YLOG_ERRNO, "Failed to create ZOOM Connection");
+ ZOOM_options_destroy(zoptions);
return -1;
}
- if (zproxy && *zproxy)
- con->zproxy = xstrdup(zproxy);
-
- if (!con->zproxy)
+ if (sru && *sru)
{
- /* no Z39.50 proxy needed - direct connect */
- yaz_log(YLOG_DEBUG, "Connection create %s", connection_get_url(con));
-
- if (!(addr = cs_straddr(link, host->ipport)))
- {
- yaz_log(YLOG_WARN|YLOG_ERRNO,
- "Lookup of IP address %s failed", host->ipport);
- return -1;
- }
-
- } else {
- /* Z39.50 proxy connect */
- yaz_log(YLOG_DEBUG, "Connection create %s proxy %s",
- connection_get_url(con), con->zproxy);
-
- if (!(addr = cs_straddr(link, con->zproxy)))
- {
- yaz_log(YLOG_WARN|YLOG_ERRNO,
- "Lookup of ZProxy IP address %s failed",
- con->zproxy);
- return -1;
- }
+ char http_hostport[512];
+ strcpy(http_hostport, "http://");
+ strcat(http_hostport, host->hostport);
+ ZOOM_connection_connect(link, http_hostport, 0);
}
+ else
+ ZOOM_connection_connect(link, host->ipport, 0);
- res = cs_connect(link, addr);
- if (res < 0)
- {
- yaz_log(YLOG_WARN|YLOG_ERRNO, "cs_connect %s",
- connection_get_url(con));
- return -1;
- }
con->link = link;
+ con->iochan = iochan_create(-1, connection_handler, 0, "connection_socket");
con->state = Conn_Connecting;
- con->iochan = iochan_create(cs_fileno(link), connection_handler, 0);
- iochan_settimeout(con->iochan, global_parameters.z3950_connect_timeout);
+ iochan_settimeout(con->iochan, con->operation_timeout);
iochan_setdata(con->iochan, con);
- pazpar2_add_channel(con->iochan);
+ iochan_add(iochan_man, con->iochan);
/* this fragment is bad DRY: from client_prep_connection */
client_set_state(con->client, Client_Connecting);
- iochan_setflag(con->iochan, EVENT_OUTPUT);
+ ZOOM_options_destroy(zoptions);
return 0;
}
-const char *connection_get_url(struct connection *co)
-{
- return client_get_url(co->client);
-}
-
-void connection_set_authentication(struct connection *co, char *auth)
-{
- co->authentication = auth;
-}
-
// Ensure that client has a connection associated
-int client_prep_connection(struct client *cl)
+int client_prep_connection(struct client *cl,
+ int operation_timeout, int session_timeout,
+ iochan_man_t iochan_man,
+ const struct timeval *abstime)
{
struct connection *co;
- struct session *se = client_get_session(cl);
struct host *host = client_get_host(cl);
struct session_database *sdb = client_get_database(cl);
- char *zproxy = session_setting_oneval(sdb, PZ_ZPROXY);
+ const char *zproxy = session_setting_oneval(sdb, PZ_ZPROXY);
if (zproxy && zproxy[0] == '\0')
zproxy = 0;
+ if (!host)
+ return 0;
+
co = client_get_connection(cl);
yaz_log(YLOG_DEBUG, "Client prep %s", client_get_url(cl));
if (!co)
{
+ int max_connections = 0;
+ int reuse_connections = 1;
+ const char *v = session_setting_oneval(client_get_database(cl),
+ PZ_MAX_CONNECTIONS);
+ if (v && *v)
+ max_connections = atoi(v);
+
+ v = session_setting_oneval(client_get_database(cl),
+ PZ_REUSE_CONNECTIONS);
+ if (v && *v)
+ reuse_connections = atoi(v);
+
// See if someone else has an idle connection
// We should look at timestamps here to select the longest-idle connection
- for (co = host->connections; co; co = co->next)
- if (co->state == Conn_Open &&
- (!co->client || client_get_session(co->client) != se) &&
- !strcmp(co->authentication,
- session_setting_oneval(client_get_database(cl),
- PZ_AUTHENTICATION)))
- {
- if (zproxy == 0 && co->zproxy == 0)
- break;
- if (zproxy && co->zproxy && !strcmp(zproxy, co->zproxy))
+ yaz_mutex_enter(host->mutex);
+ while (1)
+ {
+ int num_connections = 0;
+ for (co = host->connections; co; co = co->next)
+ num_connections++;
+ if (reuse_connections) {
+ for (co = host->connections; co; co = co->next)
+ {
+ if (connection_is_idle(co) &&
+ (!co->client || client_get_state(co->client) == Client_Idle) &&
+ !strcmp(ZOOM_connection_option_get(co->link, "user"),
+ session_setting_oneval(client_get_database(cl),
+ PZ_AUTHENTICATION)))
+ {
+ if (zproxy == 0 && co->zproxy == 0)
+ break;
+ if (zproxy && co->zproxy && !strcmp(zproxy, co->zproxy))
+ break;
+ }
+ }
+ if (co)
+ {
+ yaz_log(YLOG_LOG, "num_connections = %d (reusing)", num_connections);
break;
+ }
+ }
+ if (max_connections <= 0 || num_connections < max_connections)
+ {
+ yaz_log(YLOG_LOG, "num_connections = %d (new); max = %d",
+ num_connections, max_connections);
+ break;
}
+ yaz_log(YLOG_LOG, "num_connections = %d (waiting) max = %d",
+ num_connections, max_connections);
+ if (yaz_cond_wait(host->cond_ready, host->mutex, abstime))
+ {
+ yaz_log(YLOG_LOG, "out of connections %s", client_get_url(cl));
+ client_set_state(cl, Client_Error);
+ yaz_mutex_leave(host->mutex);
+ return 0;
+ }
+ }
if (co)
{
connection_release(co);
client_set_connection(cl, co);
co->client = cl;
+ /* ensure that connection is only assigned to this client
+ by marking the client non Idle */
+ client_set_state(cl, Client_Working);
+ yaz_mutex_leave(host->mutex);
+ co->operation_timeout = operation_timeout;
+ co->session_timeout = session_timeout;
+ /* tells ZOOM to reconnect if necessary. Disabled becuase
+ the ZOOM_connection_connect flushes the task queue */
+ ZOOM_connection_connect(co->link, 0, 0);
}
else
- co = connection_create(cl);
- }
- if (co)
- {
- if (co->state == Conn_Connecting)
- {
- client_set_state(cl, Client_Connecting);
- iochan_setflag(co->iochan, EVENT_OUTPUT);
- }
- else if (co->state == Conn_Open)
{
- if (client_get_state(cl) == Client_Error
- || client_get_state(cl) == Client_Disconnected)
- client_set_state(cl, Client_Idle);
- iochan_setflag(co->iochan, EVENT_OUTPUT);
+ yaz_mutex_leave(host->mutex);
+ co = connection_create(cl, operation_timeout, session_timeout,
+ iochan_man);
}
- return 1;
}
+
+ if (co && co->link)
+ return 1;
else
return 0;
}
-
-
/*
* Local variables:
* c-basic-offset: 4
+ * c-file-style: "Stroustrup"
* indent-tabs-mode: nil
* End:
* vim: shiftwidth=4 tabstop=8 expandtab
*/
+