Add libpq connection timeout parameter.

Denis A Ustimenko

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index ca2d7e4..4d604b2 100644 (file)
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -1,5 +1,5 @@
 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.92 2002/08/15 03:00:59 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/libpq.sgml,v 1.93 2002/08/17 12:33:17 momjian Exp $
 -->
 
  <chapter id="libpq">
@@ -172,6 +172,15 @@ PGconn *PQconnectdb(const char *conninfo)
     </varlistentry>
 
     <varlistentry>
+     <term><literal>connect_timeout</literal></term>
+     <listitem>
+     <para>
+      Time space in seconds given to connect routine. Zero or not set means infinite.
+     </para>
+     </listitem>
+    </varlistentry>
+
+    <varlistentry>
      <term><literal>options</literal></term>
      <listitem>
       <para>

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 4047465..25030e2 100644 (file)
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.191 2002/08/15 02:56:19 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v 1.192 2002/08/17 12:33:17 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -110,6 +110,9 @@ static const PQconninfoOption PQconninfoOptions[] = {
        {"password", "PGPASSWORD", DefaultPassword, NULL,
        "Database-Password", "*", 20},
 
+        {"connect_timeout", "PGCONNECT_TIMEOUT", NULL, NULL,
+        "Connect-timeout", "", 10}, /* strlen( INT32_MAX) == 10 */
+
        {"dbname", "PGDATABASE", NULL, NULL,
        "Database-Name", "", 20},
 
@@ -302,6 +305,8 @@ PQconnectStart(const char *conninfo)
        conn->pguser = tmp ? strdup(tmp) : NULL;
        tmp = conninfo_getval(connOptions, "password");
        conn->pgpass = tmp ? strdup(tmp) : NULL;
+      tmp = conninfo_getval(connOptions, "connect_timeout");
+      conn->connect_timeout = tmp ? strdup(tmp) : NULL;
 #ifdef USE_SSL
        tmp = conninfo_getval(connOptions, "requiressl");
        if (tmp && tmp[0] == '1')
@@ -1052,12 +1057,39 @@ connectDBComplete(PGconn *conn)
 {
        PostgresPollingStatusType flag = PGRES_POLLING_WRITING;
 
+      struct timeval remains, *rp = NULL, finish_time, start_time;
+
        if (conn == NULL || conn->status == CONNECTION_BAD)
                return 0;
 
-       for (;;)
+      /*
+       * Prepare to time calculations, if connect_timeout isn't zero.
+       */
+      if (conn->connect_timeout != NULL)
        {
+              remains.tv_sec = atoi(conn->connect_timeout);
+              if (!remains.tv_sec)
+              {
+                      conn->status = CONNECTION_BAD;
+                      return 0;
+              }
+              remains.tv_usec = 0;
+              rp = &remains;
+      }
+
+
+      while (NULL == rp || remains.tv_sec > 0 || remains.tv_sec == 0 && remains.tv_usec > 0)
+      {
                /*
+               * If connecting timeout is set, get current time.
+               */
+              if ( NULL != rp && -1 == gettimeofday(&start_time, NULL))
+              {
+                      conn->status = CONNECTION_BAD;
+                      return 0;
+              }
+
+              /*
                 * Wait, if necessary.  Note that the initial state (just after
                 * PQconnectStart) is to wait for the socket to select for
                 * writing.
@@ -1071,7 +1103,7 @@ connectDBComplete(PGconn *conn)
                                return 1;               /* success! */
 
                        case PGRES_POLLING_READING:
-                               if (pqWait(1, 0, conn))
+                              if (pqWaitTimed(1, 0, conn, rp))
                                {
                                        conn->status = CONNECTION_BAD;
                                        return 0;
@@ -1079,7 +1111,7 @@ connectDBComplete(PGconn *conn)
                                break;
 
                        case PGRES_POLLING_WRITING:
-                               if (pqWait(0, 1, conn))
+                              if (pqWaitTimed(0, 1, conn, rp))
                                {
                                        conn->status = CONNECTION_BAD;
                                        return 0;
@@ -1096,7 +1128,31 @@ connectDBComplete(PGconn *conn)
                 * Now try to advance the state machine.
                 */
                flag = PQconnectPoll(conn);
+
+              /*
+               * If connecting timeout is set, calculate remain time.
+               */
+              if (NULL != rp) {
+                      if (-1 == gettimeofday(&finish_time, NULL))
+                      {
+                              conn->status = CONNECTION_BAD;
+                              return 0;
+                      }
+                      if (0 > (finish_time.tv_usec -= start_time.tv_usec))
+                      {
+                              remains.tv_sec++;
+                              finish_time.tv_usec += 1000000;
+                      }
+                      if (0 > (remains.tv_usec -= finish_time.tv_usec))
+                      {
+                              remains.tv_sec--;
+                              remains.tv_usec += 1000000;
+                      }
+                      remains.tv_sec -= finish_time.tv_sec - start_time.tv_sec;
+              }
        }
+      conn->status = CONNECTION_BAD;
+      return 0;
 }
 
 /* ----------------
@@ -1928,6 +1984,8 @@ freePGconn(PGconn *conn)
                free(conn->pguser);
        if (conn->pgpass)
                free(conn->pgpass);
+      if (conn->connect_timeout)
+              free(conn->connect_timeout);
        /* Note that conn->Pfdebug is not ours to close or free */
        if (conn->notifyList)
                DLFreeList(conn->notifyList);

diff --git a/src/interfaces/libpq/fe-misc.c b/src/interfaces/libpq/fe-misc.c
index 1799b3c..be91d79 100644 (file)
--- a/src/interfaces/libpq/fe-misc.c
+++ b/src/interfaces/libpq/fe-misc.c
@@ -25,7 +25,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.76 2002/06/20 20:29:54 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-misc.c,v 1.77 2002/08/17 12:33:18 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -776,10 +776,19 @@ pqFlush(PGconn *conn)
 int
 pqWait(int forRead, int forWrite, PGconn *conn)
 {
+      return pqWaitTimed( forRead, forWrite, conn, (const struct timeval *) NULL);
+}
+
+int
+pqWaitTimed(int forRead, int forWrite, PGconn *conn, const struct timeval *timeout)
+{
        fd_set          input_mask;
        fd_set          output_mask;
        fd_set          except_mask;
 
+      struct timeval  tmp_timeout;
+      struct timeval  *ptmp_timeout = NULL;
+
        if (conn->sock < 0)
        {
                printfPQExpBuffer(&conn->errorMessage,
@@ -807,9 +816,18 @@ retry5:
                if (forWrite)
                        FD_SET(conn->sock, &output_mask);
                FD_SET(conn->sock, &except_mask);
-               if (select(conn->sock + 1, &input_mask, &output_mask, &except_mask,
-                                  (struct timeval *) NULL) < 0)
+
+              if (NULL != timeout)
                {
+              /*
+               * select may modify timeout argument on some platforms use copy
+               */
+                      tmp_timeout = *timeout;
+                      ptmp_timeout = &tmp_timeout;
+              }
+              if (select(conn->sock + 1, &input_mask, &output_mask,
+                            &except_mask, ptmp_timeout) < 0)
+              {
                        if (SOCK_ERRNO == EINTR)
                                goto retry5;
                        printfPQExpBuffer(&conn->errorMessage,

diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index aee2fce..2ee819f 100644 (file)
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -12,7 +12,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: libpq-int.h,v 1.52 2002/07/20 05:43:31 momjian Exp $
+ * $Id: libpq-int.h,v 1.53 2002/08/17 12:33:18 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -286,6 +286,8 @@ struct pg_conn
        PQExpBufferData workBuffer; /* expansible string */
 
        int                     client_encoding;        /* encoding id */
+
+      char *connect_timeout;
 };
 
 /* String descriptions of the ExecStatusTypes.
@@ -332,6 +334,7 @@ extern int  pqReadData(PGconn *conn);
 extern int     pqFlush(PGconn *conn);
 extern int     pqSendSome(PGconn *conn);
 extern int     pqWait(int forRead, int forWrite, PGconn *conn);
+extern int    pqWaitTimed(int forRead, int forWrite, PGconn *conn, const struct timeval* timeout);
 extern int     pqReadReady(PGconn *conn);
 extern int     pqWriteReady(PGconn *conn);