[Help-smalltalk] [PATCH] Various bugfixes

[Paolo Bonzini]

Found while developing the next patch I'll send.  Applied to both 2.3 
and 3.0.

The most notable ones are: 1) a finalization race, which teaches you not 
to use finalizable objects in an instance variable, if an object can be 
resurrected during its own finalizer; 2) moving #pathTo: to Directory, 
the semantics otherwise were not that clear.

Paolo

2007-06-29  Paolo Bonzini  <address@hidden>

        * kernel/File.st: Move #pathTo:...
        * kernel/Directory.st: ... here, and mimic what File>>#pathFrom: does.

        * kernel/VFS.st: Free stat into the RealFileHandler's finalizer.
        Move responsibility of registering an object with VFS's ObjectMemory
        handler to the object, rather than doing this in #addToBeFinalized.
        Fixes race where stat was finalized before an object that was later
        resurrected. 

        * libgst/lib.c: Ensure null termination of _gst_image_file_path.


--- orig/kernel/Directory.st
+++ mod/kernel/Directory.st
@@ -169,6 +169,13 @@ create: dirName
 
 !Directory methodsFor: 'accessing'!
 
+pathTo: destName
+    "Compute the relative path from the receiver to destName."
+    ^File
+        computePathFrom: vfsHandler realFileName, '/somefile'
+        to: (File fullNameFor: destName)
+!
+
 fileAt: aName
     "Answer a File object for a file named `aName' residing in the
      directory represented by the receiver."


--- orig/kernel/File.st
+++ mod/kernel/File.st
@@ -564,13 +564,6 @@ pathFrom: dirName
        to: vfsHandler realFileName
 !
 
-pathTo: destName
-    "Compute the relative path from the receiver to destName."
-    ^File
-       computePathFrom: vfsHandler realFileName
-       to: (File fullNameFor: destName)
-!
-
 symlinkFrom: srcName
     "Create the receiver as a symbolic link from srcName (relative to the
      path of the receiver)."


--- orig/kernel/VFS.st
+++ mod/kernel/VFS.st
@@ -281,11 +281,6 @@ vfsFor: fileName name: fsName subPath: s
 
 !VFSHandler methodsFor: 'releasing'!
 
-addToBeFinalized
-    "Something that has to be finalized will also be released before quitting."
-    VFSHandler addDependent: self.
-    super addToBeFinalized!
-
 finalize
     "Upon finalization, we remove the file that was temporarily holding the 
file
      contents"
@@ -504,11 +499,19 @@ lastModifyTime
     ^self getDateAndTime: self stat stMtime value
 !
 
+finalize
+    "Free the statistics for the receiver"
+    | statVar |
+    statVar := stat.
+    stat := nil.
+    statVar free
+!
+
 refresh
     "Refresh the statistics for the receiver"
     stat isNil ifTrue: [
         stat := CStatStruct new.
-        stat addToBeFinalized
+        self addToBeFinalized
     ].
     self lstatOn: self realFileName into: stat.
     File checkError.
@@ -526,8 +529,14 @@ exists
     "Answer whether a file with the name contained in the receiver does exist."
     stat isNil ifTrue: [
         stat := CStatStruct new.
-        stat addToBeFinalized.
+        self addToBeFinalized.
     ].
+    self lstatOn: self realFileName into: stat.
+    File errno == 0 ifFalse: [ ^false ].
+
+    isSymbolicLink := (stat stMode value bitAnd: 8r170000) = 8r120000. 
"S_IFLNK"
+    isSymbolicLink ifFalse: [ ^true ].
+
     self statOn: self realFileName into: stat.
     ^File errno == 0
 !
@@ -689,6 +698,7 @@ vfsFor: file name: fsName subPath: subPa
 name: virtualFileName realFileName: temporaryFileName
     "Private - Initialize a new object storing the contents of the
      virtualFileName file into temporaryFileName."
+    VFSHandler addDependent: self.
     self addToBeFinalized.
     self name: virtualFileName.
     realFileName := File fullNamFor: temporaryFileName!
@@ -769,6 +779,7 @@ at: aName
 
     handlers isNil ifTrue: [
        handlers := LookupTable new.
+       VFSHandler addDependent: self.
        self addToBeFinalized
     ].
 


--- orig/libgst/lib.c
+++ mod/libgst/lib.c
@@ -631,7 +631,8 @@ init_paths (void)
            char *dirname;
            int n = p > _gst_binary_image_name ? p - _gst_binary_image_name : 1;
            dirname = xmalloc (n + 1);
-           strncpy (dirname, _gst_binary_image_name, n);
+           memcpy (dirname, _gst_binary_image_name, n);
+           dirname[n] = 0;
            _gst_image_file_path = dirname;
            break;
          }


--- orig/tests/local.at
+++ mod/tests/local.at
@@ -21,11 +21,11 @@ dnl AT_CHECK_GST([COMMAND-LINE], [IMAGE]
 dnl ----------------------------------------------------------------
 m4_define([AT_CHECK_GST], [
   case $AUTOTEST_PATH in
-    tests) GST="$abs_top_builddir/gst -I m4_ifval([$2], [$2], 
[$abs_top_builddir/gst.im])" ;;
-    *) GST="$AUTOTEST_PATH/gst m4_ifval([$2], [-I $2])" ;;
+    tests) image_path="-I m4_ifval([$2], [$2], [$abs_top_builddir/gst.im])" ;;
+    *) image_path="m4_ifval([$2], [-I $2])" ;;
   esac
 
-  AT_CHECK([cd m4_ifval([$3], [$3], [$abs_top_builddir]) && $GST $1 | tr -d 
'\r'], 0, [$4], [$5])
+  AT_CHECK([{ (cd m4_ifval([$3], [$3], [$abs_top_builddir]) && gst $image_path 
$1); echo exit $? > retcode; } | tr -d '\r'; . retcode], 0, [$4], [$5])
 ])
 
 dnl AT_DIFF_TEST([FILE], [XFAILS])