libcoro/coro.h

/*
 * Copyright (c) 2001-2008 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.
 * 
 *   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
 * 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.
 *
 * 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.
 */

#ifndef CORO_H
#define CORO_H

#define CORO_VERSION 2

/*
 * Changes since API version 1:
 * replaced bogus -DCORO_LOOSE with gramatically more correct -DCORO_LOSER
 */

/*
 * 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. At the moment you have to define which kind
 * of implementation flavour you want:
 *
 * -DCORO_UCONTEXT
 *
 *    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)
 *
 * -DCORO_LINUX
 *
 *    Old GNU/Linux systems (<= glibc-2.1) work with this implementation
 *    (it is very fast and therefore recommended over other methods).
 *
 * -DCORO_LOSER
 *
 *    Microsoft's highly proprietary platform doesn't support sigaltstack, and
 *    this automatically selects a suitable workaround for this platform.
 *    (untested)
 *
 * -DCORO_IRIX
 *
 *    SGI's version of Microsoft's NT ;)
 *
 * -DCORO_ASM
 *
 *    Handcoded assembly, known to work only on a few architectures/ABI:
 *    ELF Linux x86 && amd64 when gcc is used and optimisation is turned on.
 *
 * 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
 * alternatives you should check (e.g. using autoconf) and define the
 * following symbols: HAVE_UCONTEXT_H / HAVE_SETJMP_H / HAVE_SIGALTSTACK.
 */

/*
 * 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, so there is
 * no coro_destroy function.
 */
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);
 */

/*
 * That was it. No other user-visible functions are implemented here.
 */

/*****************************************************************************/

#if !defined(CORO_LOSER) && !defined(CORO_UCONTEXT) \
    && !defined(CORO_SJLJ) && !defined(CORO_LINUX) \
    && !defined(CORO_IRIX) && !defined(CORO_ASM)
# if defined(WINDOWS)
#  define CORO_LOSER 1 /* you don't win with windoze */
# 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)
#  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))

#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX

# if defined(CORO_LINUX) && !defined(_GNU_SOURCE)
#  define _GNU_SOURCE /* for linux libc */
# endif

# include <setjmp.h>

struct coro_context {
  jmp_buf env;
};

# if CORO_LINUX || (_XOPEN_SOURCE >= 600)
#  define coro_transfer(p,n) do { if (!_setjmp ((p)->env)) _longjmp ((n)->env, 1); } while (0)
# else
#  define coro_transfer(p,n) do { if (!setjmp  ((p)->env)) longjmp  ((n)->env, 1); } while (0)
# endif

#elif CORO_ASM

struct coro_context {
  volatile void **sp;
};

void __attribute__ ((__noinline__, __fastcall__))
     coro_transfer(coro_context *prev, coro_context *next);

#endif

#endif

Revision:	1.23
Committed:	Sun Jan 20 17:30:24 2008 UTC (16 years, 4 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-4_4
Changes since 1.22:	+2 -1 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* Copyright (c) 2001-2008 Marc Alexander Lehmann <schmorp@schmorp.de>
3	*
4	* Redistribution and use in source and binary forms, with or without modifica-
5	* tion, are permitted provided that the following conditions are met:
6	*
7	* 1. Redistributions of source code must retain the above copyright notice,
8	* this list of conditions and the following disclaimer.
9	*
10	* 2. Redistributions in binary form must reproduce the above copyright
11	* notice, this list of conditions and the following disclaimer in the
12	* documentation and/or other materials provided with the distribution.
13	*
14	* 3. The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.
16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19	* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20	* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21	* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22	* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23	* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24	* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25	* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26	* OF THE POSSIBILITY OF SUCH DAMAGE.
27	*
28	* This library is modelled strictly after Ralf S. Engelschalls article at
29	* http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
30	* go to Ralf S. Engelschall <rse@engelschall.com>.
31	*
32	* This coroutine library is very much stripped down. You should either
33	* build your own process abstraction using it or - better - just use GNU
34	* Portable Threads, http://www.gnu.org/software/pth/.
35	*
36	*/
37
38	/*
39	* 2006-10-26 Include stddef.h on OS X to work around one of its bugs.
40	* Reported by Michael_G_Schwern.
41	* 2006-11-26 Use _setjmp instead of setjmp on GNU/Linux.
42	* 2007-04-27 Set unwind frame info if gcc 3+ and ELF is detected.
43	* Use _setjmp instead of setjmp on _XOPEN_SOURCE >= 600.
44	* 2007-05-02 Add assembly versions for x86 and amd64 (to avoid reliance
45	* on SIGUSR2 and sigaltstack in Crossfire).
46	* 2008-01-21 Disable CFI usage on anything but GNU/Linux.
47	*/
48
49	#ifndef CORO_H
50	#define CORO_H
51
52	#define CORO_VERSION 2
53
54	/*
55	* Changes since API version 1:
56	* replaced bogus -DCORO_LOOSE with gramatically more correct -DCORO_LOSER
57	*/
58
59	/*
60	* This library consists of only three files
61	* coro.h, coro.c and LICENSE (and optionally README)
62	*
63	* It implements what is known as coroutines, in a hopefully
64	* portable way. At the moment you have to define which kind
65	* of implementation flavour you want:
66	*
67	* -DCORO_UCONTEXT
68	*
69	* This flavour uses SUSv2's get/set/swap/makecontext functions that
70	* unfortunately only newer unices support.
71	* Use this for GNU/Linux + glibc-2.2.3 and possibly higher.
72	*
73	* -DCORO_SJLJ
74	*
75	* This flavour uses SUSv2's setjmp/longjmp and sigaltstack functions to
76	* do it's job. Coroutine creation is much slower than UCONTEXT, but
77	* context switching is often a bit cheaper. It should work on almost
78	* all unices. Use this for GNU/Linux + glibc-2.2. glibc-2.1 and below
79	* do not work with any sane model (neither sigaltstack nor context
80	* functions are implemented)
81	*
82	* -DCORO_LINUX
83	*
84	* Old GNU/Linux systems (<= glibc-2.1) work with this implementation
85	* (it is very fast and therefore recommended over other methods).
86	*
87	* -DCORO_LOSER
88	*
89	* Microsoft's highly proprietary platform doesn't support sigaltstack, and
90	* this automatically selects a suitable workaround for this platform.
91	* (untested)
92	*
93	* -DCORO_IRIX
94	*
95	* SGI's version of Microsoft's NT ;)
96	*
97	* -DCORO_ASM
98	*
99	* Handcoded assembly, known to work only on a few architectures/ABI:
100	* ELF Linux x86 && amd64 when gcc is used and optimisation is turned on.
101	*
102	* If you define neither of these symbols, coro.h will try to autodetect
103	* the model. This currently works for CORO_LOSER only. For the other
104	* alternatives you should check (e.g. using autoconf) and define the
105	* following symbols: HAVE_UCONTEXT_H / HAVE_SETJMP_H / HAVE_SIGALTSTACK.
106	*/
107
108	/*
109	* This is the type for the initialization function of a new coroutine.
110	*/
111	typedef void (coro_func)(void );
112
113	/*
114	* A coroutine state is saved in the following structure. Treat it as an
115	* opaque type. errno and sigmask might be saved, but don't rely on it,
116	* implement your own switching primitive if you need that.
117	*/
118	typedef struct coro_context coro_context;
119
120	/*
121	* This function creates a new coroutine. Apart from a pointer to an
122	* uninitialised coro_context, it expects a pointer to the entry function
123	* and the single pointer value that is given to it as argument.
124	*
125	* Allocating/deallocating the stack is your own responsibility, so there is
126	* no coro_destroy function.
127	*/
128	void coro_create (coro_context ctx, / an uninitialised coro_context */
129	coro_func coro, /* the coroutine code to be executed */
130	void arg, / a single pointer passed to the coro */
131	void sptr, / start of stack area */
132	long ssize); /* size of stack area */
133
134	/*
135	* The following prototype defines the coroutine switching function. It is
136	* usually implemented as a macro, so watch out.
137	*
138	void coro_transfer(coro_context prev, coro_context next);
139	*/
140
141	/*
142	* That was it. No other user-visible functions are implemented here.
143	*/
144
145	/*****************************************************************************/
146
147	#if !defined(CORO_LOSER) && !defined(CORO_UCONTEXT) \
148	&& !defined(CORO_SJLJ) && !defined(CORO_LINUX) \
149	&& !defined(CORO_IRIX) && !defined(CORO_ASM)
150	# if defined(WINDOWS)
151	# define CORO_LOSER 1 /* you don't win with windoze */
152	# elif defined(__linux) && (defined(__x86) \|\| defined (__amd64))
153	# define CORO_ASM 1
154	# elif defined(HAVE_UCONTEXT_H)
155	# define CORO_UCONTEXT 1
156	# elif defined(HAVE_SETJMP_H) && defined(HAVE_SIGALTSTACK)
157	# define CORO_SJLJ 1
158	# else
159	error unknown or unsupported architecture
160	# endif
161	#endif
162
163	/*****************************************************************************/
164
165	#if CORO_UCONTEXT
166
167	# include <ucontext.h>
168
169	struct coro_context {
170	ucontext_t uc;
171	};
172
173	# define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc))
174
175	#elif CORO_SJLJ \|\| CORO_LOSER \|\| CORO_LINUX \|\| CORO_IRIX
176
177	# if defined(CORO_LINUX) && !defined(_GNU_SOURCE)
178	# define _GNU_SOURCE /* for linux libc */
179	# endif
180
181	# include <setjmp.h>
182
183	struct coro_context {
184	jmp_buf env;
185	};
186
187	# if CORO_LINUX \|\| (_XOPEN_SOURCE >= 600)
188	# define coro_transfer(p,n) do { if (!_setjmp ((p)->env)) _longjmp ((n)->env, 1); } while (0)
189	# else
190	# define coro_transfer(p,n) do { if (!setjmp ((p)->env)) longjmp ((n)->env, 1); } while (0)
191	# endif
192
193	#elif CORO_ASM
194
195	struct coro_context {
196	volatile void **sp;
197	};
198
199	void __attribute__ ((__noinline__, __fastcall__))
200	coro_transfer(coro_context prev, coro_context next);
201
202	#endif
203
204	#endif
205