426 lines
15 KiB
C
426 lines
15 KiB
C
/*
|
|
* Copyright (c) 2001-2012,2015 Marc Alexander Lehmann <schmorp@schmorp.de>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without modifica-
|
|
* tion, are permitted provided that the following conditions are met:
|
|
*
|
|
* 1. Redistributions of source code must retain the above copyright notice,
|
|
* this list of conditions and the following disclaimer.
|
|
*
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* 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
|
|
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
|
|
* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
|
|
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
|
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
|
|
* 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
|
|
* go to Ralf S. Engelschall <rse@engelschall.com>.
|
|
*
|
|
* This coroutine library is very much stripped down. You should either
|
|
* build your own process abstraction using it or - better - just use GNU
|
|
* Portable Threads, http://www.gnu.org/software/pth/.
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* 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).
|
|
* 2011-05-30 set initial callee-saved-registers to zero with CORO_ASM.
|
|
* use .cfi_undefined rip on linux-amd64 for better backtraces.
|
|
* 2011-06-08 maybe properly implement weird windows amd64 calling conventions.
|
|
* 2011-07-03 rely on __GCC_HAVE_DWARF2_CFI_ASM for cfi detection.
|
|
* 2011-08-08 cygwin trashes stacks, use pthreads with double stack on cygwin.
|
|
* 2012-12-04 reduce misprediction penalty for x86/amd64 assembly switcher.
|
|
* 2012-12-05 experimental fiber backend (allocates stack twice).
|
|
* 2012-12-07 API version 3 - add coro_stack_alloc/coro_stack_free.
|
|
* 2012-12-21 valgrind stack registering was broken.
|
|
* 2015-12-05 experimental asm be for arm7, based on a patch by Nick Zavaritsky.
|
|
* use __name__ for predefined symbols, as in libecb.
|
|
* enable guard pages on arm, aarch64 and mips.
|
|
*/
|
|
|
|
#ifndef CORO_H
|
|
#define CORO_H
|
|
|
|
#if __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/*
|
|
* This library consists of only three files
|
|
* coro.h, coro.c and LICENSE (and optionally README)
|
|
*
|
|
* It implements what is known as coroutines, in a hopefully
|
|
* portable way.
|
|
*
|
|
* All compiletime symbols must be defined both when including coro.h
|
|
* (using libcoro) as well as when compiling coro.c (the implementation).
|
|
*
|
|
* You can manually specify which flavour you want. If you don't define
|
|
* any of these, libcoro tries to choose a safe and fast default:
|
|
*
|
|
* -DCORO_UCONTEXT
|
|
*
|
|
* This flavour uses SUSv2's get/set/swap/makecontext functions that
|
|
* unfortunately only some unices support, and is quite slow.
|
|
*
|
|
* -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 a bit cheaper. It should work on almost all unices.
|
|
*
|
|
* -DCORO_LINUX
|
|
*
|
|
* CORO_SJLJ variant.
|
|
* 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
|
|
*
|
|
* CORO_SJLJ variant.
|
|
* Microsoft's highly proprietary platform doesn't support sigaltstack, and
|
|
* this selects a suitable workaround for this platform. It might not work
|
|
* with your compiler though - it has only been tested with MSVC 6.
|
|
*
|
|
* -DCORO_FIBER
|
|
*
|
|
* Slower, but probably more portable variant for the Microsoft operating
|
|
* system, using fibers. Ignores the passed stack and allocates it internally.
|
|
* Also, due to bugs in cygwin, this does not work with cygwin.
|
|
*
|
|
* -DCORO_IRIX
|
|
*
|
|
* CORO_SJLJ variant.
|
|
* For SGI's version of Microsoft's NT ;)
|
|
*
|
|
* -DCORO_ASM
|
|
*
|
|
* Hand coded assembly, known to work only on a few architectures/ABI:
|
|
* GCC + arm7/x86/IA32/amd64/x86_64 + GNU/Linux and a few BSDs. Fastest
|
|
* choice, if it works.
|
|
*
|
|
* -DCORO_PTHREAD
|
|
*
|
|
* Use the pthread API. You have to provide <pthread.h> 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 best/safest model. To help with the autodetection, you should check
|
|
* (e.g. using autoconf) and define the following symbols: HAVE_UCONTEXT_H
|
|
* / HAVE_SETJMP_H / HAVE_SIGALTSTACK.
|
|
*/
|
|
|
|
/*
|
|
* Changes when the API changes incompatibly.
|
|
* This is ONLY the API version - there is no ABI compatibility between releases.
|
|
*
|
|
* Changes in API version 2:
|
|
* replaced bogus -DCORO_LOOSE with grammatically more correct -DCORO_LOSER
|
|
* Changes in API version 3:
|
|
* introduced stack management (CORO_STACKALLOC)
|
|
*/
|
|
#define CORO_VERSION 3
|
|
|
|
#include <stddef.h>
|
|
|
|
/*
|
|
* This is the type for the initialization function of a new coroutine.
|
|
*/
|
|
typedef void (*coro_func)(void *);
|
|
|
|
/*
|
|
* 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 if you need that.
|
|
*/
|
|
typedef struct coro_context coro_context;
|
|
|
|
/*
|
|
* This function creates a new coroutine. Apart from a pointer to an
|
|
* 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.
|
|
*
|
|
* As a special case, if coro, arg, sptr and ssze 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, /* 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 */
|
|
size_t ssze); /* size of stack area in bytes */
|
|
|
|
/*
|
|
* The following prototype defines the coroutine switching function. It is
|
|
* sometimes implemented as a macro, so watch out.
|
|
*
|
|
* 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 sometimes 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
|
|
|
|
/*****************************************************************************/
|
|
/* optional stack management */
|
|
/*****************************************************************************/
|
|
/*
|
|
* You can disable all of the stack management functions by
|
|
* defining CORO_STACKALLOC to 0. Otherwise, they are enabled by default.
|
|
*
|
|
* If stack management is enabled, you can influence the implementation via these
|
|
* symbols:
|
|
*
|
|
* -DCORO_USE_VALGRIND
|
|
*
|
|
* If defined, then libcoro will include valgrind/valgrind.h and register
|
|
* and unregister stacks with valgrind.
|
|
*
|
|
* -DCORO_GUARDPAGES=n
|
|
*
|
|
* libcoro will try to use the specified number of guard pages to protect against
|
|
* stack overflow. If n is 0, then the feature will be disabled. If it isn't
|
|
* defined, then libcoro will choose a suitable default. If guardpages are not
|
|
* supported on the platform, then the feature will be silently disabled.
|
|
*/
|
|
#ifndef CORO_STACKALLOC
|
|
# define CORO_STACKALLOC 1
|
|
#endif
|
|
|
|
#if CORO_STACKALLOC
|
|
|
|
/*
|
|
* The only allowed operations on these struct members is to read the
|
|
* "sptr" and "ssze" members to pass it to coro_create, to read the "sptr"
|
|
* member to see if it is false, in which case the stack isn't allocated,
|
|
* and to set the "sptr" member to 0, to indicate to coro_stack_free to
|
|
* not actually do anything.
|
|
*/
|
|
|
|
struct coro_stack
|
|
{
|
|
void *sptr;
|
|
size_t ssze;
|
|
#if CORO_USE_VALGRIND
|
|
int valgrind_id;
|
|
#endif
|
|
};
|
|
|
|
/*
|
|
* Try to allocate a stack of at least the given size and return true if
|
|
* successful, or false otherwise.
|
|
*
|
|
* The size is *NOT* specified in bytes, but in units of sizeof (void *),
|
|
* i.e. the stack is typically 4(8) times larger on 32 bit(64 bit) platforms
|
|
* then the size passed in.
|
|
*
|
|
* If size is 0, then a "suitable" stack size is chosen (usually 1-2MB).
|
|
*/
|
|
int coro_stack_alloc (struct coro_stack *stack, unsigned int size);
|
|
|
|
/*
|
|
* Free the stack allocated by coro_stack_alloc again. It is safe to
|
|
* call this function on the coro_stack structure even if coro_stack_alloc
|
|
* failed.
|
|
*/
|
|
void coro_stack_free (struct coro_stack *stack);
|
|
|
|
#endif
|
|
|
|
/*
|
|
* That was it. No other user-serviceable parts below here.
|
|
*/
|
|
|
|
/*****************************************************************************/
|
|
|
|
#if !defined CORO_LOSER && !defined CORO_UCONTEXT \
|
|
&& !defined CORO_SJLJ && !defined CORO_LINUX \
|
|
&& !defined CORO_IRIX && !defined CORO_ASM \
|
|
&& !defined CORO_PTHREAD && !defined CORO_FIBER
|
|
# if defined WINDOWS && (defined __i386__ || (__x86_64__ || defined _M_IX86 || defined _M_AMD64))
|
|
# define CORO_ASM 1
|
|
# elif defined WINDOWS || defined _WIN32
|
|
# define CORO_LOSER 1 /* you don't win with windoze */
|
|
# elif __linux && (__i386__ || (__x86_64__ && !__ILP32__) || (__arm__ && __ARCH_ARCH == 7))
|
|
# define CORO_ASM 1
|
|
# elif defined HAVE_UCONTEXT_H
|
|
# define CORO_UCONTEXT 1
|
|
# elif defined HAVE_SETJMP_H && defined HAVE_SIGALTSTACK
|
|
# define CORO_SJLJ 1
|
|
# else
|
|
error unknown or unsupported architecture
|
|
# endif
|
|
#endif
|
|
|
|
/*****************************************************************************/
|
|
|
|
#if CORO_UCONTEXT
|
|
|
|
# include <ucontext.h>
|
|
|
|
struct coro_context
|
|
{
|
|
ucontext_t 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 glibc */
|
|
# endif
|
|
|
|
# if !CORO_LOSER
|
|
# include <unistd.h>
|
|
# endif
|
|
|
|
/* solaris is hopelessly borked, it expands _XOPEN_UNIX to nothing */
|
|
# if __sun
|
|
# undef _XOPEN_UNIX
|
|
# define _XOPEN_UNIX 1
|
|
# endif
|
|
|
|
# include <setjmp.h>
|
|
|
|
# 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
|
|
{
|
|
void **sp; /* must be at offset 0 */
|
|
};
|
|
|
|
#if __i386__ || __x86_64__
|
|
void __attribute__ ((__noinline__, __regparm__(2)))
|
|
#else
|
|
void __attribute__ ((__noinline__))
|
|
#endif
|
|
coro_transfer (coro_context *prev, coro_context *next);
|
|
|
|
# define coro_destroy(ctx) (void *)(ctx)
|
|
|
|
#elif CORO_PTHREAD
|
|
|
|
# include <pthread.h>
|
|
|
|
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);
|
|
|
|
#elif CORO_FIBER
|
|
|
|
struct coro_context
|
|
{
|
|
void *fiber;
|
|
/* only used for initialisation */
|
|
coro_func coro;
|
|
void *arg;
|
|
};
|
|
|
|
void coro_transfer (coro_context *prev, coro_context *next);
|
|
void coro_destroy (coro_context *ctx);
|
|
|
|
#endif
|
|
|
|
#if __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif
|
|
|