2000-05-29 Sandeep Tamhankar <sandeep@scriptics.com>

	* tests/http.test
	* doc/http.n
	* library/http2.3/http.tcl: Fixed bug 5741, where unsuccessful
	geturl calls sometimes leaked memory and resources (sockets).
	Also, switched around some of the logic so that http::wait never
	throws an exception.  This is because in an asynchronous geturl,
	the command callback will probably end up doing all the error
	handling anyway, and in an asynchronous situation, the user
	expects to check the state when the transaction completes, as
	opposed to being thrown an exception.	For the http package, this
	menas the user can check http::status for "error" and http::error
	for the error message after doing the http::wait.

1 files changed, 40 insertions, 23 deletions

diff --git a/library/http/http.tcl b/library/http/http.tcl
index a524415..c8c9908 100644
--- a/library/http/http.tcl
+++ b/library/http/http.tcl
@@ -9,7 +9,7 @@
 # See the file "license.terms" for information on usage and
 # redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 #
-# RCS: @(#) $Id: http.tcl,v 1.32 2000/04/22 07:07:59 sandeep Exp $
+# RCS: @(#) $Id: http.tcl,v 1.33 2000/06/02 23:14:46 hobbs Exp $
 
 # Rough version history:
 # 1.0	Old http_get interface
@@ -280,7 +280,7 @@ proc http::geturl { url args } {
     if {![regexp -nocase {^(([^:]*)://)?([^/:]+)(:([0-9]+))?(/.*)?$} $url \
 	    x prefix proto host y port srvurl]} {
 	unset $token
-	error "Unsupported URL: $url"
+	return -code error "Unsupported URL: $url"
     }
     if {[string length $proto] == 0} {
 	set proto http
@@ -288,7 +288,7 @@ proc http::geturl { url args } {
     }
     if {![info exists urlTypes($proto)]} {
 	unset $token
-	return -code error "unsupported url type \"$proto\""
+	return -code error "Unsupported URL type \"$proto\""
     }
     set defport [lindex $urlTypes($proto) 0]
     set defcmd [lindex $urlTypes($proto) 1]
@@ -345,12 +345,17 @@ proc http::geturl { url args } {
     if {$state(-timeout) > 0} {
 	fileevent $s writable [list http::Connect $token]
 	http::wait $token
-	if {$state(status) != "connect"} {
-	    
-	    # Likely to be connection timeout.  If there was a connection
-	    # error, (e.g., bad port), then http::wait will have 
-	    # raised an error already
 
+	if {[string equal $state(status) "error"]} {
+	    # something went wrong while trying to establish the connection
+	    # Clean up after events and such, but DON'T call the command
+	    # callback (if available) because we're going to throw an 
+	    # exception from here instead.
+	    set err [lindex $state(error) 0]
+	    cleanup $token
+	    return -code error $err
+	} elseif {![string equal $state(status) "connect"]} {
+	    # Likely to be connection timeout
 	    return $token
 	}
 	set state(status) ""
@@ -449,6 +454,11 @@ proc http::geturl { url args } {
 	    # calls it synchronously, we just do a wait here.
 
 	    wait $token
+	    if {[string equal $state(status) "error"]} {
+		# Something went wrong, so throw the exception, and the
+		# enclosing catch will do cleanup.
+		return -code error [lindex $state(error) 0]
+	    }		
 	}
     } err]} {
 	# The socket probably was never connected,
@@ -457,8 +467,12 @@ proc http::geturl { url args } {
 	# Clean up after events and such, but DON'T call the command callback
 	# (if available) because we're going to throw an exception from here
 	# instead.
-
-	Finish $token $err 1
+	
+	# if state(status) is error, it means someone's already called Finish
+	# to do the above-described clean up.
+	if {[string equal $state(status) "error"]} {
+	    Finish $token $err 1
+	}
 	cleanup $token
 	return -code error $err
     }
@@ -502,6 +516,15 @@ proc http::size {token} {
     return $state(currentsize)
 }
 
+proc http::error {token} {
+    variable $token
+    upvar 0 $token state
+    if {[info exists state(error)]} {
+	return $state(error)
+    }
+    return ""
+}
+
 # http::cleanup
 #
 #	Garbage collect the state associated with a transaction
@@ -531,21 +554,19 @@ proc http::cleanup {token} {
 #	Sets the status of the connection, which unblocks
 # 	the waiting geturl call
 
- proc http::Connect {token} {
+proc http::Connect {token} {
     variable $token
     upvar 0 $token state
     global errorInfo errorCode
     if {[eof $state(sock)] ||
-	    [string length [fconfigure $state(sock) -error]]} {
-	set state(status) error
-	set state(error) [list \
-		"connect failed [fconfigure $state(sock) -error]" \
-		$errorInfo $errorCode]
+	[string length [fconfigure $state(sock) -error]]} {
+	    Finish $token "connect failed [fconfigure $state(sock) -error]" 1
     } else {
 	set state(status) connect
+	fileevent $state(sock) writable {}
     }
-    fileevent $state(sock) writable {}
- }
+    return
+}
 
 # http::Write
 #
@@ -780,11 +801,7 @@ proc http::wait {token} {
 	# We must wait on the original variable name, not the upvar alias
 	vwait $token\(status)
     }
-    if {[info exists state(error)]} {
-	set errorlist $state(error)
-	unset state
-	eval error $errorlist
-    }
+
     return $state(status)
 }