--- libcoro/coro.h 2006/02/19 22:30:58 1.13 +++ libcoro/coro.h 2010/12/03 19:21:59 1.44 @@ -1,5 +1,5 @@ /* - * Copyright (c) 2001-2005 Marc Alexander Lehmann + * Copyright (c) 2001-2009 Marc Alexander Lehmann * * Redistribution and use in source and binary forms, with or without modifica- * tion, are permitted provided that the following conditions are met: @@ -11,9 +11,6 @@ * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * - * 3. The name of the author may not be used to endorse or promote products - * derived from this software without specific prior written permission. - * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO @@ -25,8 +22,19 @@ * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * + * Alternatively, the contents of this file may be used under the terms of + * the GNU General Public License ("GPL") version 2 or any later version, + * in which case the provisions of the GPL are applicable instead of + * the above. If you wish to allow the use of your version of this file + * only under the terms of the GPL and not to allow others to use your + * version of this file under the BSD license, indicate your decision + * by deleting the provisions above and replace them with the notice + * and other provisions required by the GPL. If you do not delete the + * provisions above, a recipient may use your version of this file under + * either the BSD or the GPL. + * * This library is modelled strictly after Ralf S. Engelschalls article at - * http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must + * http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must * go to Ralf S. Engelschall . * * This coroutine library is very much stripped down. You should either @@ -35,9 +43,42 @@ * */ +/* + * 2006-10-26 Include stddef.h on OS X to work around one of its bugs. + * Reported by Michael_G_Schwern. + * 2006-11-26 Use _setjmp instead of setjmp on GNU/Linux. + * 2007-04-27 Set unwind frame info if gcc 3+ and ELF is detected. + * Use _setjmp instead of setjmp on _XOPEN_SOURCE >= 600. + * 2007-05-02 Add assembly versions for x86 and amd64 (to avoid reliance + * on SIGUSR2 and sigaltstack in Crossfire). + * 2008-01-21 Disable CFI usage on anything but GNU/Linux. + * 2008-03-02 Switched to 2-clause BSD license with GPL exception. + * 2008-04-04 New (but highly unrecommended) pthreads backend. + * 2008-04-24 Reinstate CORO_LOSER (had wrong stack adjustments). + * 2008-10-30 Support assembly method on x86 with and without frame pointer. + * 2008-11-03 Use a global asm statement for CORO_ASM, idea by pippijn. + * 2008-11-05 Hopefully fix misaligned stacks with CORO_ASM/SETJMP. + * 2008-11-07 rbp wasn't saved in CORO_ASM on x86_64. + * introduce coro_destroy, which is a nop except for pthreads. + * speed up CORO_PTHREAD. Do no longer leak threads either. + * coro_create now allows one to create source coro_contexts. + * do not rely on makecontext passing a void * correctly. + * try harder to get _setjmp/_longjmp. + * major code cleanup/restructuring. + * 2008-11-10 the .cfi hacks are no longer needed. + * 2008-11-16 work around a freebsd pthread bug. + * 2008-11-19 define coro_*jmp symbols for easier porting. + * 2009-06-23 tentative win32-backend support for mingw32 (Yasuhiro Matsumoto). + * 2010-12-03 tentative support for uclibc (which lacks all sorts of things). + */ + #ifndef CORO_H #define CORO_H +#if __cplusplus +extern "C" { +#endif + #define CORO_VERSION 2 /* @@ -57,21 +98,19 @@ * * This flavour uses SUSv2's get/set/swap/makecontext functions that * unfortunately only newer unices support. - * Use this for GNU/Linux + glibc-2.2.3 and possibly higher. * * -DCORO_SJLJ * * This flavour uses SUSv2's setjmp/longjmp and sigaltstack functions to * do it's job. Coroutine creation is much slower than UCONTEXT, but * context switching is often a bit cheaper. It should work on almost - * all unices. Use this for GNU/Linux + glibc-2.2. glibc-2.1 and below - * do not work with any sane model (neither sigaltstack nor context - * functions are implemented) + * all unices. * * -DCORO_LINUX * - * Old GNU/Linux systems (<= glibc-2.1) work with this implementation - * (it is very fast and therefore recommended over other methods). + * Old GNU/Linux systems (<= glibc-2.1) only work with this implementation + * (it is very fast and therefore recommended over other methods, but + * doesn't work with anything newer). * * -DCORO_LOSER * @@ -83,8 +122,19 @@ * * SGI's version of Microsoft's NT ;) * + * -DCORO_ASM + * + * Handcoded assembly, known to work only on a few architectures/ABI: + * GCC + x86/IA32 and amd64/x86_64 + GNU/Linux and a few BSDs. + * + * -DCORO_PTHREAD + * + * Use the pthread API. You have to provide and -lpthread. + * This is likely the slowest backend, and it also does not support fork(), + * so avoid it at all costs. + * * If you define neither of these symbols, coro.h will try to autodetect - * the model. This currently works for CORO_LOSER only. For the other + * the model. This currently works for CORO_LOSER only. For the other * alternatives you should check (e.g. using autoconf) and define the * following symbols: HAVE_UCONTEXT_H / HAVE_SETJMP_H / HAVE_SIGALTSTACK. */ @@ -95,9 +145,9 @@ typedef void (*coro_func)(void *); /* - * A coroutine state is saved in the following structure. Treat it as a + * A coroutine state is saved in the following structure. Treat it as an * opaque type. errno and sigmask might be saved, but don't rely on it, - * implement your own switching primitive. + * implement your own switching primitive if you need that. */ typedef struct coro_context coro_context; @@ -106,19 +156,43 @@ * uninitialised coro_context, it expects a pointer to the entry function * and the single pointer value that is given to it as argument. * - * Allocating/deallocating the stack is your own responsibility, so there is - * no coro_destroy function. + * Allocating/deallocating the stack is your own responsibility. + * + * As a special case, if coro, arg, sptr and ssize are all zero, + * then an "empty" coro_context will be created that is suitable + * as an initial source for coro_transfer. + * + * This function is not reentrant, but putting a mutex around it + * will work. */ -void coro_create (coro_context *ctx, - coro_func coro, void *arg, - void *sptr, long ssize); +void coro_create (coro_context *ctx, /* an uninitialised coro_context */ + coro_func coro, /* the coroutine code to be executed */ + void *arg, /* a single pointer passed to the coro */ + void *sptr, /* start of stack area */ + long ssize); /* size of stack area */ /* * The following prototype defines the coroutine switching function. It is * usually implemented as a macro, so watch out. * -void coro_transfer(coro_context *prev, coro_context *next); + * This function is thread-safe and reentrant. */ +#if 0 +void coro_transfer (coro_context *prev, coro_context *next); +#endif + +/* + * The following prototype defines the coroutine destroy function. It is + * usually implemented as a macro, so watch out. It also serves + * no purpose unless you want to use the CORO_PTHREAD backend, + * where it is used to clean up the thread. You are responsible + * for freeing the stack and the context itself. + * + * This function is thread-safe and reentrant. + */ +#if 0 +void coro_destroy (coro_context *ctx); +#endif /* * That was it. No other user-visible functions are implemented here. @@ -128,10 +202,12 @@ #if !defined(CORO_LOSER) && !defined(CORO_UCONTEXT) \ && !defined(CORO_SJLJ) && !defined(CORO_LINUX) \ - && !defined(CORO_IRIX) + && !defined(CORO_IRIX) && !defined(CORO_ASM) \ + && !defined(CORO_PTHREAD) # if defined(WINDOWS) # define CORO_LOSER 1 /* you don't win with windoze */ -# elif defined(__linux) && defined(__x86) +# elif defined(__linux) && (defined(__x86) || defined (__amd64)) +# define CORO_ASM 1 # elif defined(HAVE_UCONTEXT_H) # define CORO_UCONTEXT 1 # elif defined(HAVE_SETJMP_H) && defined(HAVE_SIGALTSTACK) @@ -145,28 +221,83 @@ #if CORO_UCONTEXT -#include +# include struct coro_context { ucontext_t uc; }; -#define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc)) +# define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc)) +# define coro_destroy(ctx) (void *)(ctx) #elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX -#if defined(CORO_LINUX) && !defined(_GNU_SOURCE) -# define _GNU_SOURCE // for linux libc -#endif +# if defined(CORO_LINUX) && !defined(_GNU_SOURCE) +# define _GNU_SOURCE /* for linux libc */ +# endif -#include +# if !CORO_LOSER +# include +# endif + +/* solaris is hopelessly borked, it expands _XOPEN_UNIX to nothing */ +# if __sun +# undef _XOPEN_UNIX +# define _XOPEN_UNIX 1 +# endif + +# include + +# if _XOPEN_UNIX > 0 || defined (_setjmp) +# define coro_jmp_buf jmp_buf +# define coro_setjmp(env) _setjmp (env) +# define coro_longjmp(env) _longjmp ((env), 1) +# elif CORO_LOSER +# define coro_jmp_buf jmp_buf +# define coro_setjmp(env) setjmp (env) +# define coro_longjmp(env) longjmp ((env), 1) +# else +# define coro_jmp_buf sigjmp_buf +# define coro_setjmp(env) sigsetjmp (env, 0) +# define coro_longjmp(env) siglongjmp ((env), 1) +# endif + +struct coro_context { + coro_jmp_buf env; +}; + +# define coro_transfer(p,n) do { if (!coro_setjmp ((p)->env)) coro_longjmp ((n)->env); } while (0) +# define coro_destroy(ctx) (void *)(ctx) + +#elif CORO_ASM struct coro_context { - jmp_buf env; + void **sp; /* must be at offset 0 */ }; -#define coro_transfer(p,n) do { if (!setjmp ((p)->env)) longjmp ((n)->env, 1); } while(0) +void __attribute__ ((__noinline__, __regparm__(2))) +coro_transfer (coro_context *prev, coro_context *next); + +# define coro_destroy(ctx) (void *)(ctx) + +#elif CORO_PTHREAD + +# include + +extern pthread_mutex_t coro_mutex; + +struct coro_context { + pthread_cond_t cv; + pthread_t id; +}; + +void coro_transfer (coro_context *prev, coro_context *next); +void coro_destroy (coro_context *ctx); + +#endif +#if __cplusplus +} #endif #endif