533014 - Patches for using NSPR as static libraries

Status: NEW

(NSPR :: NSPR, enhancement)

Description

[Wan-Teh Chang]

Attachment: Patch (works on Windows with --enable-win32-target=WIN95)

I'm using this bug report to publish patches that enable
using NSPR as static libraries.

WARNING: If a process has two copies of NSPR, and an
application is not careful in isolating the copies of
NSPR (for example, passing a memory block allocated by
PR_Malloc of one copy of NSPR to PR_Free of another copy
of NSPR, or calling PR_GetError() of one copy of NSPR
after an NSPR function in another copy of NSPR failed),
things won't work.  The best way to ensure a process
has only one copy of NSPR is to use NSPR shared libraries
(DLLs).

The only feature of shared libraries/DLLs that NSPR
depends on is the DllMain DLL_THREAD_DETACH notification
that NSPR uses to detach native threads not created by
NSPR.  So I worked on Windows first.  The attached patch
allows me to build NSPR static libraries properly, and
pass all the NSPR test programs.  The key changes are:

1. In prtypes.h, I have to disable the PR_EXPORT,
PR_IMPORT, and PR_IMPLEMENT macros because they cause
NSPR public functions to be exported from a DLL or EXE
on Windows.

This change requires changes to mozilla/nsprpub/pr/tests/dll
to export symbols from the test DLL using a .def file.

2. In w95thred.c, I found an alternative solution for
detaching native threads not created by NSPR.

All the other changes are build system changes (to not
build the DLls) and test changes (to disable tests that
are applicable to DLLs only).

Some of these changes are generally useful (e.g., the
alternative to DllMain).  I will have them reviewed
and checked in to reduce the size of this patch.

Comment 1

[Wan-Teh Chang]

Attachment: Patch v2 (works on Windows with --enable-win32-target=WIN95)

Add 'extern' to PR_IMPORT and PR_IMPORT_DATA in prtypes.h.

Comment 2

[Wan-Teh Chang]

Attachment: Patch v3 (works on Windows with --enable-win32-target=WIN95 and on Mac)

Change mozilla/nsprpub/pr/tests/Makefile.in to link with
-framework CoreServices -framework CoreFoundation
on the Mac.

Comment 3

[Wan-Teh Chang]

Attachment: Patch v4 (works on Windows with --enable-win32-target=WIN95 and on Mac)

Updated the patch for NSPR 4.8.6.

The thread local storage (TLS) callback code in
mozilla/nsprpub/pr/src/md/windows/w95thred.c was
updated to survive whole program optimization.

Comment 4

[Wan-Teh Chang]

Attachment: Patch v4.1 (works on Windows with --enable-win32-target=WIN95 and on Mac)

Improved the comments.  No other changes.

Comment 5

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee is inactive on Bugzilla, so the assignee is being reset.