improve locking

git-svn-id: file:///root/webif/svn/pkg/webif/trunk@2845 2a923420-c742-0410-a762-8d5b09965624

CONTROL/control

@@ -1,7 +1,7 @@
 Package: webif
 Priority: optional
 Section: web
-Version: 1.2.8-15
+Version: 1.2.8-16
 Architecture: mipsel
 Maintainer: af123@hpkg.tv
 Depends: tcpfix,webif-channelicons(>=1.1.20),lighttpd(>=1.4.39-1),jim(>=0.76-1),jim-oo,jim-sqlite3(>=0.76),jim-cgi(>=0.7-1),jim-binary(>=0.76),service-control(>=2.1),busybox(>=1.20.2-1),lsof(>=4.87),epg(>=1.2.1-1),hmt(>=2.0.9),ssmtp,cron-daemon(>=1.18.3-3),at(>=3.1.18),anacron,trm(>=1.1),openssl-command,nicesplice,id3v2,file,rsvsync(>=1.0.2),webif-charts(>=1.2-1),stripts(>=1.2.5-3),tmenu(>=1.08),ffmpeg,id3v2,multienv(>=1.6),tcpping(>=1.1),e2fsprogs,wireless-tools(>=29-1),dbupdate,recmon(>=2.0.7)

webif/lib/fileops

@@ -56,6 +56,7 @@ proc {file touch} {target {ref ""}} {
 }
 
 proc {file tdelete} {target} {
+	try {
 		if {[file isdirectory $target]} {
 			foreach f [readdir -nocomplain $target] {
 				file tdelete "$target/$f"
@@ -64,9 +65,14 @@ proc {file tdelete} {target} {
 		} else {
 			exec /mod/bin/trm $target
 		}
+	} on error {msg opts} {
+		incr opts(-level)
+		return {*}$opts $msg
+	}
 }
 
 proc {file read} {target {bytes 0}} {
+	try {
 		if {[file readable $target]} {
 			set fd [open $target]
 			if {$bytes} {
@@ -78,24 +84,39 @@ proc {file read} {target {bytes 0}} {
 			return $ret
 		}
 		error "Cannot read $target"
+	} on error {msg opts} {
+		incr opts(-level)
+		return {*}$opts $msg
+	}
 }
 
 proc {file write} {target content} {
+	try {
 		if {[catch {set fd [open $target w]} msg]} {
 			error "Open failed, $msg"
 		} else {
 			$fd puts -nonewline $content
 			$fd close
 		}
+	} on error {msg opts} {
+		incr opts(-level)
+		return {*}$opts $msg
+	}
 }
 
 set ::fileops::locks {}
 
-proc {file lock} {target} {
+proc {file lock} {{create {}} target} {
+	try {
+		if {$create ni {{} -create}} {
+			error "bad option \"$create\": should be -create"
+		}
 		if {[dict exists $::fileops::locks $target]} {
 			return 0
 		}
-	if {[catch {set fd [open $target w]} msg]} {
+		if {$create eq "" && ![file exists $target]} {
+			error "'$target' does not exist"
+		} elseif {[catch {set fd [open $target w]} msg]} {
 			error "open '$target' failed, $msg"
 		} else {
 			set ret [$fd lock]
@@ -106,9 +127,14 @@ proc {file lock} {target} {
 			}
 			return $ret
 		}
+	} on error {msg opts} {
+		incr opts(-level)
+		return {*}$opts $msg
+	}
 }
 
 proc {file unlock} {target} {
+	try {
 		if {[dict exists $::fileops::locks $target]} {
 			set fd $::fileops::locks($target)
 			dict unset ::fileops::locks $target
@@ -117,6 +143,10 @@ proc {file unlock} {target} {
 			return $ret
 		}
 		error "$target was not locked."
+	} on error {msg opts} {
+		incr opts(-level)
+		return {*}$opts $msg
+	}
 }
 
 local proc file {cmd args} {

webif/lib/lock

@@ -1,50 +1,47 @@
 #!/mod/bin/jimsh
 
-set ::_lock::locks {}
+set ::lock::locks {}
-
-# For testing, 'ababab' collides with 'b'
-
-proc ::_lock::hash {id} {{hashes {}}} {
-	set len [string length $id]
-	set hash $len
-
-	for {set i 0} {$i < $len} {incr i} {
-		scan [string index $id $i] "%c" asc
-		set hash [expr (($hash<<5)^($hash>>27))^$asc];
-	}
-
-	set hash [expr (65535 - ($hash % 101))]
-
-	while {[dict exists $hashes $hash] && $hashes($hash) ne $id} {
-		#puts "Hash collision."
-		if {[incr hash] > 65535} { set hash 32768 }
-	}
-	set hashes($hash) $id
-
-	return $hash
-}
 
 proc acquire_lock {id {timeout 0} {interval 0.2}} {
-	set port [::_lock::hash $id]
+	try {
+		if {[dict exists $::lock::locks $id]} {
+			#error "Lock already held"
+			set lock $::lock::locks($id)
+		} else {
+			set file "/var/lock/.webiflock_[system filename $id]"
+			set fh [open $file w]
+			set lock [list file $file fh $fh]
+			set ::lock::locks($id) $lock
+		}
+
 		incr timeout [clock seconds]
 
-	while {[catch {set socket [\
+		while {[$lock(fh) lock] != 1} {
-	    socket stream.server "127.0.0.1:$port"]} msg]} {
 			if {[clock seconds] > $timeout} { return 0 }
 			sleep $interval
 		}
 
-	set ::_lock::locks($id) $socket
 		return 1
+	} on error {msg opts} {
+		incr opts(-level)
+		return {*}$opts $msg
+	}
 }
 
 proc release_lock {id} {
-	if {![dict exists $::_lock::locks $id]} { return 0 }
+	try {
-	if {[catch {close $::_lock::locks($id)} msg]} {
+		if {![dict exists $::lock::locks $id]} {
-		#puts "Error releasing lock: $msg"
+			error "Lock not held."
-		return 0
+		}
+		set lock $::lock::locks($id)
+
+		set ret [$lock(fh) unlock]
+		$lock(fh) close
+		dict unset ::lock::locks $id
+		return $ret
+	} on error {msg opts} {
+		incr opts(-level)
+		return {*}$opts $msg
 	}
-	unset ::_lock::locks($id)
-	return 1
 }