[Issue 1968] New: boxer.d does not work
d-bugmail at puremagic.com
d-bugmail at puremagic.com
Tue Apr 1 08:41:19 PDT 2008
http://d.puremagic.com/issues/show_bug.cgi?id=1968
Summary: boxer.d does not work
Product: DGCC aka GDC
Version: unspecified
Platform: Macintosh
OS/Version: Mac OS X
Status: NEW
Severity: normal
Priority: P2
Component: Phobos
AssignedTo: dvdfrdmn at users.sf.net
ReportedBy: fawzi at gmx.ch
Doing my tangobos merge I came across a bug in std.boxer.
Actually in phobos it passes the unit tests, but is still broken.
The issue can be seen with the following program
==========
import std.stdio;
import std.boxer;
void main()
{
auto array=boxArray("ab","cd","ef");
assert(unbox!(char[])(array[0])=="ab");
assert(unbox!(char[])(array[1])=="cd");
assert(unbox!(char[])(array[2])=="ef");
writefln(unbox!(char[])(array[2]));
}
========
The main issue is that the generic handling does not update _argptr.
doing a modification like this
- array[index] = box(ti_orig, cast(void*) _argptr);
+ void *v=cast(void*)_argptr;
+ array[index] = box(ti_orig, v);
+ // update _argptr
+ v+=ti.tsize;
+ void **vv=cast(void**)&_argptr;
+ *vv=v;
fixes the problem, at least on MacOsX.
Still this is a dangerous operation because it makes assumptions on _argptr
(that from now on the arguments are on the stack and a pointer to them is the
first element in va_list).
So I also added to the function a lot of special cases (all basic types, arrays
of them and all pointer types) in the dumb way (by typing them out).
I think that this way it should be rather safe, and work in most occasions.
Here is the patch wit a slight change in the import and an extra cast.
--- boxer.d (revision 209)
+++ boxer.d (working copy)
@@ -68,10 +68,9 @@
module std.boxer;
private import std.format;
+import std.stdarg;
private import std.string;
private import std.utf;
-version (GNU)
- private import std.stdarg;
/* These functions and types allow packing objects into generic containers
* and recovering them later. This comes into play in a wide spectrum of
@@ -502,7 +501,7 @@
/**
* Box each argument passed to the function, returning an array of boxes.
- */
+ */
Box[] boxArray(...)
{
version (GNU)
@@ -517,28 +516,128 @@
while ( (ttd = cast(TypeInfo_Typedef) ti) !is null )
ti = ttd.base;
- if (ti is typeid(float))
+ if (ti is typeid(bool))
{
- float f = va_arg!(float)(_argptr);
- array[index] = box(ti_orig, cast(void *) & f);
+ auto a = va_arg!(bool)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
}
else if (ti is typeid(char) || ti is typeid(byte) || ti is
typeid(ubyte))
{
- byte b = va_arg!(byte)(_argptr);
- array[index] = box(ti_orig, cast(void *) & b);
+ auto a = va_arg!(byte)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
}
- else if (ti is typeid(wchar) || ti is typeid(short) || ti is
typeid(ushort))
+ else if (ti is typeid(wchar))
{
- short s = va_arg!(short)(_argptr);
- array[index] = box(ti_orig, cast(void *) & s);
+ auto a = va_arg!(wchar)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
}
- else if (ti is typeid(bool))
+ else if (ti is typeid(short) || ti is typeid(ushort))
{
- bool b = va_arg!(bool)(_argptr);
- array[index] = box(ti_orig, cast(void *) & b);
+ auto a = va_arg!(short)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
}
- else
- array[index] = box(ti_orig, cast(void*) _argptr);
+ else if (ti is typeid(int) || ti is typeid(uint))
+ {
+ auto a = va_arg!(int)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(long) || ti is typeid(ulong))
+ {
+ auto a = va_arg!(long)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(float) || ti is typeid(ifloat))
+ {
+ auto a = va_arg!(float)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(double) || ti is typeid(idouble))
+ {
+ auto a = va_arg!(double)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(real) || ti is typeid(ireal))
+ {
+ auto a = va_arg!(real)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(bool[]))
+ {
+ auto a = va_arg!(bool[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(char[]) || ti is typeid(byte[]) || ti is
typeid(ubyte[]))
+ {
+ auto a = va_arg!(byte[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(wchar[]))
+ {
+ auto a = va_arg!(wchar[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(short[]) || ti is typeid(ushort[]))
+ {
+ auto a = va_arg!(short[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(int[]) || ti is typeid(uint[]))
+ {
+ auto a = va_arg!(int[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(long[]) || ti is typeid(ulong[]))
+ {
+ auto a = va_arg!(long[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(float[]) || ti is typeid(ifloat[]))
+ {
+ auto a = va_arg!(float[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(double[]) || ti is typeid(idouble[]))
+ {
+ auto a = va_arg!(double[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(real[]) || ti is typeid(ireal[]))
+ {
+ auto a = va_arg!(real[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(cfloat[]))
+ {
+ auto a = va_arg!(cfloat[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(cdouble[]))
+ {
+ auto a = va_arg!(cdouble[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti is typeid(creal[]))
+ {
+ auto a = va_arg!(creal[])(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else if (ti.tsize == (void *).sizeof)
+ { // treats all pointer based cases
+ void *a = va_arg!(void *)(_argptr);
+ array[index] = box(ti_orig, cast(void *) & a);
+ }
+ else
+ {
+ // structures passed on the stack
+ // assumes a stack based storage, and that the pointer to it
+ // can be retrived via cast...
+ void *v=cast(void*)_argptr;
+ array[index] = box(ti_orig, v);
+ // update _argptr
+ v+=ti.tsize;
+ void **vv=cast(void**)&_argptr; // this is dangerous...
+ *vv=v; // ... very dangerous... but seems to work ;)
+ }
}
return array;
@@ -797,7 +896,7 @@
if (isArrayTypeInfo(value.type))
return (*cast(void[]*) value.data).ptr;
if (cast(TypeInfo_Class) value.type)
- return *cast(Object*) value.data;
+ return cast(T)(*cast(Object*) value.data);
throw new UnboxException(value, typeid(T));
}
--
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