SHORT-DESCRIPTION:
-----------------

The existing code for the offending tests (see attached .jtr file) doesn't work
on platforms that aren't utilizing 8-bit bytes and 2's-complement arithmetic.
Just to summarize the key points about the invalid platform assumptions being
made by these tests:

1) A signed value is being placed into an unsigned field.
2) The code assumes that the most significant bit for a char type is 0x80.
3) The code assumes that the least significant bit is set for both positive and negative odd values.


LONG-DESCRIPTION:
----------------

We have some questions as the result of our investigation of one of the
api/java_text tests that fails
(javasoft.sqe.tests.api.java.text.Bidi.ctorTests).

When a new instance of BiDi is created, the second parameter to the constructor
is an int field that can possibly be a negative number. The constructor in
BiDi.java looks as follows:

     public Bidi(String paragraph, int flags)
Some of the possible values passed as the 2nd parameter are:

     public static final int DIRECTION_DEFAULT_LEFT_TO_RIGHT = -2;
     public static final int DIRECTION_DEFAULT_RIGHT_TO_LEFT = -1;

The int field flags is passed to native code (jbidi.c) as a jint (still
retains the sign). It is passed as the last parameter (dir) as follows:

 JNIEXPORT void JNICALL Java_java_text_Bidi_nativeBidiChars
   (JNIEnv *env, jclass cls, jobject jbidi, jcharArray text, jint tStart, jbyteArray embs, jint eStart, jint length, jint dir)

The following line then casts the int field dir to an unsigned char:

    UBiDiLevel baseLevel = (UBiDiLevel)dir;

Why is a signed field being cast to an unsigned field?

The routine ubidi_setPara (ubidi.c) is then called passing this unsigned
field:

     ubidi_setPara(bidi, cText + tStart, length, baseLevel, cEmbsAdj, &err);

The routine ubidi_setPara does numeric comparisons on this unsigned char field
(paraLevel):

    if(pBiDi==NULL || text==NULL ||
               (UBIDI_MAX_EXPLICIT_LEVEL<paraLevel) && !IS_DEFAULT_LEVEL(paraLevel) ||
               length<-1

Why are numeric comparisons being done on this unsigned field? In addition,
the IS_DEFAULT_LEVEL macro is doing some bit manipulation that would only
appear to work on platforms with 8-bit bytes and 2's complement arithmetic.
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