From 456e6c73abe4920da074c9a0e4561267808ef81e Mon Sep 17 00:00:00 2001
From: Howard Chu <hyc@openldap.org>
Date: Thu, 29 Aug 2002 12:12:36 +0000
Subject: [PATCH] Fix ITS#1983, handle writing of large requests. Only one
 pending request is allowed per LDAP* handle. It works, but needs review.

---
 libraries/libldap/abandon.c  |  2 +-
 libraries/libldap/ldap-int.h |  1 +
 libraries/libldap/request.c  | 71 ++++++++++++++++++++++++------------
 libraries/libldap/result.c   |  6 +++
 4 files changed, 55 insertions(+), 25 deletions(-)

diff --git a/libraries/libldap/abandon.c b/libraries/libldap/abandon.c
index a88a5865b5..04397a275e 100644
--- a/libraries/libldap/abandon.c
+++ b/libraries/libldap/abandon.c
@@ -224,7 +224,7 @@ do_abandon(
 	}
 
 	if ( lr != NULL ) {
-		if ( sendabandon ) {
+		if ( sendabandon || lr->lr_status == LDAP_REQST_WRITING ) {
 			ldap_free_connection( ld, lr->lr_conn, 0, 1 );
 		}
 		if ( origid == msgid ) {
diff --git a/libraries/libldap/ldap-int.h b/libraries/libldap/ldap-int.h
index 4ad20dd9f4..5e44c3287d 100644
--- a/libraries/libldap/ldap-int.h
+++ b/libraries/libldap/ldap-int.h
@@ -467,6 +467,7 @@ LDAP_F (int) ldap_chase_referrals( LDAP *ld, LDAPRequest *lr,
 LDAP_F (int) ldap_chase_v3referrals( LDAP *ld, LDAPRequest *lr,
 	char **refs, int sref, char **referralsp, int *hadrefp );
 LDAP_F (int) ldap_append_referral( LDAP *ld, char **referralsp, char *s );
+LDAP_F (int) ldap_int_flush_request( LDAP *ld, LDAPRequest *lr );
 
 /*
  * in result.c:
diff --git a/libraries/libldap/request.c b/libraries/libldap/request.c
index b9ecd9b3bd..c45a7769f5 100644
--- a/libraries/libldap/request.c
+++ b/libraries/libldap/request.c
@@ -137,6 +137,39 @@ ldap_send_initial_request(
 }
 
 
+int
+ldap_int_flush_request(
+	LDAP *ld,
+	LDAPRequest *lr
+)
+{
+	LDAPConn *lc = lr->lr_conn;
+
+	if ( ber_flush( lc->lconn_sb, lr->lr_ber, 0 ) != 0 ) {
+		if ( errno == EWOULDBLOCK || errno == EAGAIN ) {
+			/* need to continue write later */
+			lr->lr_status = LDAP_REQST_WRITING;
+			ldap_mark_select_write( ld, lc->lconn_sb );
+			ld->ld_errno = LDAP_BUSY;
+			return -2;
+		} else {
+			ld->ld_errno = LDAP_SERVER_DOWN;
+			ldap_free_request( ld, lr );
+			ldap_free_connection( ld, lc, 0, 0 );
+			return( -1 );
+		}
+	} else {
+		if ( lr->lr_parent == NULL ) {
+			lr->lr_ber->ber_end = lr->lr_ber->ber_ptr;
+			lr->lr_ber->ber_ptr = lr->lr_ber->ber_buf;
+		}
+		lr->lr_status = LDAP_REQST_INPROGRESS;
+
+		/* sent -- waiting for a response */
+		ldap_mark_select_read( ld, lc->lconn_sb );
+	}
+	return 0;
+}
 
 int
 ldap_send_server_request(
@@ -189,6 +222,18 @@ ldap_send_server_request(
 	}
 
 	use_connection( ld, lc );
+
+	/* If we still have an incomplete write, try to finish it before
+	 * dealing with the new request. If we don't finish here, return
+	 * LDAP_BUSY and let the caller retry later. We only allow a single
+	 * request to be in WRITING state.
+	 */
+	if ( ld->ld_requests &&
+		ld->ld_requests->lr_status == LDAP_REQST_WRITING &&
+		ldap_int_flush_request( ld, ld->ld_requests ) < 0 ) {
+		return -1;
+	}
+
 	if (( lr = (LDAPRequest *)LDAP_CALLOC( 1, sizeof( LDAPRequest ))) ==
 	    NULL ) {
 		ld->ld_errno = LDAP_NO_MEMORY;
@@ -225,30 +270,8 @@ ldap_send_server_request(
 	ld->ld_requests = lr;
 	lr->lr_prev = NULL;
 
-	if ( ber_flush( lc->lconn_sb, ber, 0 ) != 0 ) {
-#ifdef notyet
-		if ( errno == EWOULDBLOCK ) {
-			/* need to continue write later */
-			lr->lr_status = LDAP_REQST_WRITING;
-			ldap_mark_select_write( ld, lc->lconn_sb );
-		} else {
-#else /* notyet */
-			ld->ld_errno = LDAP_SERVER_DOWN;
-			ldap_free_request( ld, lr );
-			ldap_free_connection( ld, lc, 0, 0 );
-			return( -1 );
-#endif /* notyet */
-#ifdef notyet
-		}
-#endif /* notyet */
-	} else {
-		if ( parentreq == NULL ) {
-			ber->ber_end = ber->ber_ptr;
-			ber->ber_ptr = ber->ber_buf;
-		}
-
-		/* sent -- waiting for a response */
-		ldap_mark_select_read( ld, lc->lconn_sb );
+	if ( ldap_int_flush_request( ld, lr ) == -1 ) {
+		return -1;
 	}
 
 	ld->ld_errno = LDAP_SUCCESS;
diff --git a/libraries/libldap/result.c b/libraries/libldap/result.c
index 1a7bcec9ef..2f82aa9422 100644
--- a/libraries/libldap/result.c
+++ b/libraries/libldap/result.c
@@ -334,6 +334,12 @@ wait4msg(
 				    rc = -2;	/* select interrupted: loop */
 			    } else {
 				    rc = -2;
+				    if ( ld->ld_requests &&
+						ld->ld_requests->lr_status == LDAP_REQST_WRITING &&
+						ldap_is_write_ready( ld,
+							ld->ld_requests->lr_conn->lconn_sb ) ) {
+						ldap_int_flush_request( ld, ld->ld_requests );
+					}
 				    for ( lc = ld->ld_conns; rc == -2 && lc != NULL;
 				        lc = nextlc ) {
 					    nextlc = lc->lconn_next;
-- 
2.39.5