[PATCH] Add BeOS support for libstdc++-v3

[Gabriel Dos Reis]

Daniel Berlin <dan@www.cgsoftware.com> writes:

| [1  <text/plain; US-ASCII (7bit)>]
| This patch and new file add support for BeOS (including multithreaded
| support) to libstdc++.
| 
| Unfortunately, the gen-num-limits patch is necessary, or else we go into
| a 100% cpu loop due to some oddness in BeOS signal handling.
| 
| threads-beos.h goes in config.
| I didn't include a regenerated configure in the patch.

OK.  The tools needed to regenerate them can be found on the libstdc++
ftp site.

[...]

| Index: acinclude.m4

This is OK.

[...]

| Index: aclocal.m4

[...]

OK.

| Index: configure.target

[...]

OK.

| Index: mknumeric_limits
| ===================================================================
| RCS file: /cvs/gcc/egcs/libstdc++-v3/mknumeric_limits,v
| retrieving revision 1.4
| diff -c -3 -p -r1.4 mknumeric_limits
| *** mknumeric_limits	2000/11/04 03:00:10	1.4
| --- mknumeric_limits	2000/11/18 15:31:43
| *************** case `uname` in
| *** 21,26 ****
| --- 21,28 ----
|   		LDFLAGS='-nodefaultlibs -lgcc -lc' ;;
|   	esac
|   	;;
| +     BeOS*)
| +     	LDFLAGS='-nodefaultlibs -lgcc -lroot' ;;

Could there be any note explaining the purpose of -lroot?

[...]

| Index: include/bits/stl_config.h

[...]

OK.

[...]

| Index: include/bits/stl_threads.h
| ===================================================================
| RCS file: /cvs/gcc/egcs/libstdc++-v3/include/bits/stl_threads.h,v
| retrieving revision 1.1
| diff -c -3 -p -r1.1 stl_threads.h
| *** stl_threads.h	2000/10/05 11:27:01	1.1
| --- stl_threads.h	2000/11/18 15:31:43
| ***************
| *** 34,39 ****
| --- 34,41 ----
|   #include <synch.h>
|   #elif defined(__STL_WIN32THREADS)
|   #include <windows.h>
| + #elif defined(__STL_BEOSTHREADS)
| + #include <bits/libc-lock.h>
|   #endif
|   
|   __STL_BEGIN_NAMESPACE
| *************** struct _Refcount_Base
| *** 56,61 ****
| --- 58,65 ----
|     // The type _RC_t
|   # ifdef __STL_WIN32THREADS
|     typedef long _RC_t;
| + # elif  __STL_BEOSTHREADS
| +   typedef unsigned long _RC_t;
|   # else
|     typedef size_t _RC_t;
|   #endif

OK.

| *************** struct _Refcount_Base
| *** 107,112 ****
| --- 111,124 ----
|       mutex_unlock(&_M_ref_count_lock);
|       return __tmp;
|     }
| + # elif defined(__STL_BEOSTHREADS)
| +   void _M_incr() {
| +     atomic_add(&_M_ref_count, 1);
| +   }
| +   _RC_t _M_decr() {
| +     atomic_add(&_M_ref_count, -1);
| +     return _M_ref_count;
| +   }

Formatting remarks: This should read

	void
	_M_incr()
	{ /* ... */ }

	_RC_t
	_M_decr()
	{
	   // ...
	}

Please, refer tp the C++STYLE notes.

|   # else  /* No threads */
|     void _M_incr() { ++_M_ref_count; }
|     _RC_t _M_decr() { return --_M_ref_count; }
| *************** struct _Refcount_Base
| *** 129,134 ****
| --- 141,159 ----
|       inline unsigned long _Atomic_swap(unsigned long * __p, unsigned long __q) {
|           return (unsigned long) InterlockedExchange((LPLONG)__p, (LONG)__q);
|       }
| + # elif defined(__STL_BEOSTHREADS)
| +     inline unsigned long _Atomic_swap(unsigned long *p, unsigned long newval) {

Same comments here.


| + {
| +   unsigned long retval;
| +   long int readval;
| +   __asm__ ("lock");
| +   retval = *p;
| + 
| +   __asm__ __volatile__ ("lock; xchgl %3, %1; sete %0"
| +                         : "=q" (ret), "=m" (*p), "=a" (readval)
| +                         : "r" (newval), "m" (*p));
| +   return retval;
| + }
|   # elif defined(__STL_PTHREADS)
|       // We use a template here only to get a unique initialized instance.
|       template<int __dummy>
| *************** struct _STL_mutex_lock
| *** 325,330 ****
| --- 350,360 ----
|     void _M_initialize()   { mutex_init(&_M_lock, USYNC_THREAD, 0); }
|     void _M_acquire_lock() { mutex_lock(&_M_lock); }
|     void _M_release_lock() { mutex_unlock(&_M_lock); }
| + #elif defined(__STL_BEOSTHREADS)
| +   sem_id _M_lock;
| +   void _M_initialize()   { _M_lock = create_sem(1, "STL semaphore"); }
| +   void _M_acquire_lock() { acquire_sem(_M_lock);  }
| +   void _M_release_lock() { release_sem(_M_lock);  }

Ditto.

Aprt from that, it is OK.

[...]

| Index: libio/libioP.h
| ===================================================================

OK -- but the libio bits won't properly work; that is not your fault.

[...]

| Index: libmath/mathconf.h
| ===================================================================
| RCS file: /cvs/gcc/egcs/libstdc++-v3/libmath/mathconf.h,v

This is OK.  

At some point I would completely remove this dependency.

[...]

| Index: src/gen-num-limits.cc
| ===================================================================

[...]

| + #else
| +     const char *p = "false";
| + #endif

Is this so because 1/0 need cause interruption or just because there
is no way to test the various trapping?

Otherwise, it is OK for a temporary workaround.

[...]


-- Gaby
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