Provide operation when tcl files unavailable

chpock · May 17, 2024 · 254f6b4 · 254f6b4
1 parent b10bda3
commit 254f6b4
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Showing 4 changed files with 71 additions and 75 deletions.
diff --git a/ChangeLog b/ChangeLog
@@ -1,3 +1,8 @@
+2024-05-18 Konstantin Kushnir <[email protected]>
+	* Provide successful operation when tcl files unavailable. CookFS should
+	work when readerchannel.tcl memchan.tcl pages.tcl fsindex.tcl unavailable,
+	but C module contains all required functionality.
+
 2024-05-17 Konstantin Kushnir <[email protected]>
 	* Add support for c-writerchannel. This removes the dependency on vfs::memchan and improves memory utilization/performance
 

diff --git a/scripts/cookvfs.tcl b/scripts/cookvfs.tcl
@@ -40,9 +40,6 @@ proc cookfs::sha1 {args} {
 
 proc cookfs::pages {args} {
     if {[pkgconfig get c-pages]} {
-	if {![llength [info commands ::cookfs::c::pages]]} {
-	    package require vfs::cookfs::c::pages [pkgconfig get package-version]
-	}
 	return [uplevel #0 [concat [list ::cookfs::c::pages] $args]]
     }  else  {
 	if {![llength [info commands ::cookfs::tcl::pages]]} {
@@ -54,9 +51,6 @@ proc cookfs::pages {args} {
 
 proc cookfs::fsindex {args} {
     if {[pkgconfig get c-fsindex]} {
-	if {![llength [info commands ::cookfs::c::fsindex]]} {
-	    package require vfs::cookfs::c::fsindex [pkgconfig get package-version]
-	}
 	return [uplevel #0 [concat [list ::cookfs::c::fsindex] $args]]
     }  else  {
 	if {![llength [info commands ::cookfs::tcl::fsindex]]} {
@@ -75,35 +69,39 @@ proc cookfs::initialize {} {
     variable pkginitialized
 
     if {![info exists pkginitialized]} {
-	package require vfs::cookfs::pkgconfig
-
-	# load Tcl versions of packages for now
-	package require vfs::cookfs::tcl::vfs [pkgconfig get package-version]
-	package require vfs::cookfs::tcl::memchan [pkgconfig get package-version]
-	package require vfs::cookfs::tcl::writer [pkgconfig get package-version]
-	package require vfs::cookfs::tcl::optimize [pkgconfig get package-version]
-
-	# load C version of Pages if available
-	if {[pkgconfig get c-pages]} {
-	    package require vfs::cookfs::c [pkgconfig get package-version]
-    } {
-	    package require vfs::cookfs::tcl::pages [pkgconfig get package-version]
-	}
-
-	# load C version of Fsindex if available
-	if {[pkgconfig get c-fsindex]} {
-	    package require vfs::cookfs::c [pkgconfig get package-version]
-    } {
-	    package require vfs::cookfs::tcl::fsindex [pkgconfig get package-version]
-	}
-
-    package require vfs::cookfs::tcl::readerchannel [pkgconfig get package-version]
-	# load C version of Readerchannel if available
-	if {[pkgconfig get c-readerchannel]} {
-	    package require vfs::cookfs::c [pkgconfig get package-version]
-    }
-
-	set pkginitialized 1
+        catch { package require vfs::cookfs::c }
+
+        # load Tcl version of pkgconfig if we don't have such a command in C module
+        if { ![llength [info commands cookfs::pkgconfig]] } {
+            package require vfs::cookfs::pkgconfig
+        }
+
+        # load Tcl versions of packages for now
+        package require vfs::cookfs::tcl::vfs [pkgconfig get package-version]
+        package require vfs::cookfs::tcl::writer [pkgconfig get package-version]
+        package require vfs::cookfs::tcl::optimize [pkgconfig get package-version]
+
+        # load C version of Pages if available
+        if {![pkgconfig get c-pages]} {
+            package require vfs::cookfs::tcl::pages [pkgconfig get package-version]
+        }
+
+        # load C version of Fsindex if available
+        if {![pkgconfig get c-fsindex]} {
+            package require vfs::cookfs::tcl::fsindex [pkgconfig get package-version]
+        }
+
+        # load C version of Readerchannel if available
+        if {![pkgconfig get c-readerchannel]} {
+            package require vfs::cookfs::tcl::readerchannel [pkgconfig get package-version]
+        }
+
+        # load C version of Writerchannel if available
+        if {![pkgconfig get c-writerchannel]} {
+            package require vfs::cookfs::tcl::memchan [pkgconfig get package-version]
+        }
+
+        set pkginitialized 1
     }
 
     # decide on crc32 implementation based on if zlib command is present
@@ -247,6 +245,20 @@ proc cookfs::Mount {args} {
     set fs(tclreaderchannel) [expr {$fs(tclpages) || ![pkgconfig get c-readerchannel] || $opt(tcl-readerchannel)}]
     set fs(tclwriterchannel) [expr {$fs(tclpages) || $fs(tclfsindex) || ![pkgconfig get c-writerchannel] || $opt(tcl-writerchannel)}]
 
+    # load Tcl packages if we need them but don't currently have them
+    if {$fs(tclpages) && [catch {package present vfs::cookfs::tcl::pages}]} {
+        package require vfs::cookfs::tcl::pages [pkgconfig get package-version]
+    }
+    if {$fs(tclfsindex) && [catch {package present vfs::cookfs::tcl::fsindex}]} {
+        package require vfs::cookfs::tcl::fsindex [pkgconfig get package-version]
+    }
+    if {$fs(tclreaderchannel) && [catch {package present vfs::cookfs::tcl::readerchannel}]} {
+        package require require vfs::cookfs::tcl::readerchannel [pkgconfig get package-version]
+    }
+    if {$fs(tclwriterchannel) && [catch {package present vfs::cookfs::tcl::memchan}]} {
+        package require require vfs::cookfs::tcl::memchan [pkgconfig get package-version]
+    }
+
     # initialize pages
     if {$opt(pagesobject) == ""} {
 	set pagesoptions [list -cachesize $opt(pagecachesize) \

diff --git a/scripts/readerchannel.tcl b/scripts/readerchannel.tcl
@@ -2,46 +2,16 @@
 #
 # (c) 2010 Wojciech Kocjan, Pawel Salawa
 # (c) 2011-2014 Wojciech Kocjan
+# (c) 2024 Konstantin Kushnir
 
 namespace eval cookfs {}
 
 # creates a new channel for reading data from a VFS
 # uses reflected channels
-proc cookfs::createReadableChannel {fsid path} {
+proc cookfs::createReadableChannel {fsid chunklist} {
     variable dirlistParameters
     upvar #0 $fsid fs
 
-    # try to get information about specified path
-    if {[catch {
-        set fileinfo [$fs(index) get $path]
-    }]} {
-        return ""
-    }
-
-    # return if trying to open a directory
-    if {([llength $fileinfo] != 3)} {
-        return ""
-    }
-
-    foreach {mtime size chunklist} $fileinfo break
-
-    # if this is a small file, currently pending write, pass it to memchan
-    if {([llength $chunklist] == 3) && ([lindex $chunklist 0] < 0)} {
-        #vfs::log [list cookfs::createReadableChannel $fsid $path smallfile]
-        if {!$fs(tclwriterchannel) && [pkgconfig get c-writerchannel]} {
-            return [::cookfs::c::writerchannel $fs(pages) $fs(index) $fs(writer) $path true]
-        } else {
-            return [lindex [initMemchan $fsid $path true] 0]
-        }
-    }
-
-    # create C channel if available and was not disabled
-    if {!$fs(tclreaderchannel) && [pkgconfig get c-readerchannel]} {
-	set chan [cookfs::c::readerchannel $fs(pages) $fs(index) $chunklist]
-	fconfigure $chan -buffersize 65536
-	return $chan
-    }
-
     set id [incr fs(channelId)]
     set chid "$fsid.ch$id"
     upvar #0 $chid ch

diff --git a/scripts/vfs.tcl b/scripts/vfs.tcl
@@ -255,17 +255,26 @@ proc cookfs::vfshandleOpen {fsid relative mode} {
         "" - r {
             #vfs::log [list cookfs::vfshandleOpen $fsid $relative read]
             if {[catch {
-                set channel [cookfs::createReadableChannel $fsid $relative]
-            } error]} {
-                #vfs::log [list cookfs::vfshandleOpen $fsid $relative error $::errorInfo]
+                $fs(index) get $relative
+            } fileinfo]} {
                 vfs::filesystem posixerror $::cookfs::posix(ENOENT)
             }
-
-            if {$channel == ""} {
-                #vfs::log [list cookfs::vfshandleOpen $fsid $relative {does not exist}]
-                vfs::filesystem posixerror $::cookfs::posix(ENOENT)
+            if {[llength $fileinfo] != 3} {
+                vfs::filesystem posixerror $::cookfs::posix(EISDIR)
+            }
+            foreach {mtime size chunklist} $fileinfo break
+            # if this is a small file, currently pending write, pass it to memchan
+            if {([llength $chunklist] == 3) && ([lindex $chunklist 0] < 0)} {
+                if {!$fs(tclwriterchannel) && [pkgconfig get c-writerchannel]} {
+                    set channel [::cookfs::c::writerchannel $fs(pages) $fs(index) $fs(writer) $relative true]
+                } else {
+                    set channel [lindex [initMemchan $fsid $relative true] 0]
+                }
+            } elseif {!$fs(tclreaderchannel) && [pkgconfig get c-readerchannel]} {
+                set channel [cookfs::c::readerchannel $fs(pages) $fs(index) $chunklist]
+            } else {
+                set channel [cookfs::createReadableChannel $fsid $chunklist]
             }
-
             return [list $channel ""]
         }
         r+ {