VMMaker simulation - strlen, strcpy, getenv and FakeStdinStream

 
On Sun, 14 Oct 2018 at 22:03, Alistair Grant <[hidden email]> wrote:
>
> Hi All,
>
> Just in case there aren't automatic notifications of submissions to
> VMMakerInbox...
>
> I've submitted the following changes (more information after the descriptions):

There haven't been any negative comments, and it only affects the
simulator, so I'll take this as approval. :-)

What's the process for moving a package from the inbox to the main
repository?  I can use Monticello to copy the package across easily
enough, but how to remove it from the Inbox?  (I've got write
permission for the main repository).

Thanks,
Alistair



> Name: VMMaker.oscog-AlistairGrant.2455
> Author: AlistairGrant
> Time: 14 October 2018, 8:59:01.383815 pm
> UUID: 9e8e4134-b30b-4734-9477-95d556650155
> Ancestors: VMMaker.oscog-eem.2454
>
> VMClass strlen, strncpy and getenv
>
> Pharo stores UTF8 encoded strings in ByteArrays (ByteString, strictly
> speaking, expects to only store characters that can be represented as
> a single byte in UTF8, e.g. ascii).  ByteArrays are also used within
> the simulator to represent buffers allocated by the simulator.  As
> such, the strings may either be the length of the ByteArray or less
> than the ByteArray size and null terminated.
>
> These changes extend strlen: and strncpy:_:_: to handle ByteArrays and
> add some tests (tests for strings in the object memory are todo).
>
> InterpreterPrimitives>>primitiveGetenv: returned nil rather than 0 in
> the simulator when a variable that isn't defined is requested.
>
>
> Name: VMMaker.oscog-AlistairGrant.2456
> Author: AlistairGrant
> Time: 14 October 2018, 9:25:11.249348 pm
> UUID: 47b0319d-df10-4ece-84fc-324d0d35fe1d
> Ancestors: VMMaker.oscog-AlistairGrant.2455
>
> FakeStdinStream and FilePluginSimulator do double duty with the #atEnd
> flag to allow #sqFile:Read:Into:At: to break out of its loop.  This is
> brittle as a additional calls to #atEnd breaks the simulation - which
> is what Pharo does.
>
> Instead of doing double duty with #atEnd, do the same as the actual
> plugin (sqFileReadIntoAt() in sqFilePluginBasicPrims.c) and ignore the
> number of bytes to read when input is from stdin (FakeStdinStream) and
> only ever read a single byte (fixes the problem and is closer to the
> real plugin behaviour).
>
>
> Background:
>
> I've successfully got a Pharo 7 image (with FileAttributesPlugin)
> running StdioListener in the VM simulator, but have made a few changes
> at each level:
>
> - Created a modified Pharo image that avoids FFI:
> -- It doesn't load FreeType fonts or Iceberg to avoid FFI callouts.
> -- Uses UnixOSProcessPlugin>>primitiveGetCurrentWorkingDirectory
> instead of an FFI callout.
> - StdioListener has changes to work with Zinc streams
> - VMMaker has changes (in addition to the patches above):
> -- Added UnixOSProcessPluginSimulator so that
> primitiveGetCurrentWorkingDirectory can be used instead of FFI.
>
> Can someone tell me whether FFI is expected to work within the simulator?
>
> Thanks,
> Alistair

On Mon, Oct 15, 2018 at 10:47 AM Alistair Grant <[hidden email]> wrote:

What's the process for moving a package from the inbox to the main
repository?  I can use Monticello to copy the package across easily
enough, but how to remove it from the Inbox?  (I've got write
permission for the main repository).

Simply don't bother deleting it; just leave it there.