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Revision 1.9 by root, Thu Mar 3 17:20:31 2005 UTC vs.
Revision 1.54 by root, Fri Dec 21 04:48:17 2012 UTC

1/* 1/*
2 * Copyright (c) 2001-2005 Marc Alexander Lehmann <schmorp@schmorp.de> 2 * Copyright (c) 2001-2012 Marc Alexander Lehmann <schmorp@schmorp.de>
3 * 3 *
4 * Redistribution and use in source and binary forms, with or without modifica- 4 * Redistribution and use in source and binary forms, with or without modifica-
5 * tion, are permitted provided that the following conditions are met: 5 * tion, are permitted provided that the following conditions are met:
6 * 6 *
7 * 1. Redistributions of source code must retain the above copyright notice, 7 * 1. Redistributions of source code must retain the above copyright notice,
8 * this list of conditions and the following disclaimer. 8 * this list of conditions and the following disclaimer.
9 * 9 *
10 * 2. Redistributions in binary form must reproduce the above copyright 10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the 11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution. 12 * documentation and/or other materials provided with the distribution.
13 * 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 14 * 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- 15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 16 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- 17 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 18 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
… …
23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 20 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- 21 * 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 22 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26 * OF THE POSSIBILITY OF SUCH DAMAGE. 23 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 * 24 *
25 * Alternatively, the contents of this file may be used under the terms of
26 * the GNU General Public License ("GPL") version 2 or any later version,
27 * in which case the provisions of the GPL are applicable instead of
28 * the above. If you wish to allow the use of your version of this file
29 * only under the terms of the GPL and not to allow others to use your
30 * version of this file under the BSD license, indicate your decision
31 * by deleting the provisions above and replace them with the notice
32 * and other provisions required by the GPL. If you do not delete the
33 * provisions above, a recipient may use your version of this file under
34 * either the BSD or the GPL.
35 *
28 * This library is modelled strictly after Ralf S. Engelschalls article at 36 * 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 37 * http://www.gnu.org/software/pth/rse-pmt.ps. So most of the credit must
30 * go to Ralf S. Engelschall <rse@engelschall.com>. 38 * go to Ralf S. Engelschall <rse@engelschall.com>.
31 * 39 *
32 * This coroutine library is very much stripped down. You should either 40 * This coroutine library is very much stripped down. You should either
33 * build your own process abstraction using it or - better - just use GNU 41 * build your own process abstraction using it or - better - just use GNU
34 * Portable Threads, http://www.gnu.org/software/pth/. 42 * Portable Threads, http://www.gnu.org/software/pth/.
35 * 43 *
36 */ 44 */
37 45
46/*
47 * 2006-10-26 Include stddef.h on OS X to work around one of its bugs.
48 * Reported by Michael_G_Schwern.
49 * 2006-11-26 Use _setjmp instead of setjmp on GNU/Linux.
50 * 2007-04-27 Set unwind frame info if gcc 3+ and ELF is detected.
51 * Use _setjmp instead of setjmp on _XOPEN_SOURCE >= 600.
52 * 2007-05-02 Add assembly versions for x86 and amd64 (to avoid reliance
53 * on SIGUSR2 and sigaltstack in Crossfire).
54 * 2008-01-21 Disable CFI usage on anything but GNU/Linux.
55 * 2008-03-02 Switched to 2-clause BSD license with GPL exception.
56 * 2008-04-04 New (but highly unrecommended) pthreads backend.
57 * 2008-04-24 Reinstate CORO_LOSER (had wrong stack adjustments).
58 * 2008-10-30 Support assembly method on x86 with and without frame pointer.
59 * 2008-11-03 Use a global asm statement for CORO_ASM, idea by pippijn.
60 * 2008-11-05 Hopefully fix misaligned stacks with CORO_ASM/SETJMP.
61 * 2008-11-07 rbp wasn't saved in CORO_ASM on x86_64.
62 * introduce coro_destroy, which is a nop except for pthreads.
63 * speed up CORO_PTHREAD. Do no longer leak threads either.
64 * coro_create now allows one to create source coro_contexts.
65 * do not rely on makecontext passing a void * correctly.
66 * try harder to get _setjmp/_longjmp.
67 * major code cleanup/restructuring.
68 * 2008-11-10 the .cfi hacks are no longer needed.
69 * 2008-11-16 work around a freebsd pthread bug.
70 * 2008-11-19 define coro_*jmp symbols for easier porting.
71 * 2009-06-23 tentative win32-backend support for mingw32 (Yasuhiro Matsumoto).
72 * 2010-12-03 tentative support for uclibc (which lacks all sorts of things).
73 * 2011-05-30 set initial callee-saved-registers to zero with CORO_ASM.
74 * use .cfi_undefined rip on linux-amd64 for better backtraces.
75 * 2011-06-08 maybe properly implement weird windows amd64 calling conventions.
76 * 2011-07-03 rely on __GCC_HAVE_DWARF2_CFI_ASM for cfi detection.
77 * 2011-08-08 cygwin trashes stacks, use pthreads with double stack on cygwin.
78 * 2012-12-04 reduce misprediction penalty for x86/amd64 assembly switcher.
79 * 2012-12-05 experimental fiber backend (allocates stack twice).
80 * 2012-12-07 API version 3 - add coro_stack_alloc/coro_stack_free.
81 * 2012-12-21 valgrind stack registering was broken.
82 */
83
38#ifndef CORO_H 84#ifndef CORO_H
39#define CORO_H 85#define CORO_H
40 86
41#define CORO_VERSION 1 87#if __cplusplus
88extern "C" {
89#endif
42 90
43/* 91/*
44 * This library consists of only three files 92 * This library consists of only three files
45 * coro.h, coro.c and LICENSE (and optionally README) 93 * coro.h, coro.c and LICENSE (and optionally README)
46 * 94 *
47 * It implements what is known as coroutines, in a hopefully 95 * It implements what is known as coroutines, in a hopefully
48 * portable way. At the moment you have to define which kind 96 * portable way.
49 * of implementation flavour you want: 97 *
98 * All compiletime symbols must be defined both when including coro.h
99 * (using libcoro) as well as when compiling coro.c (the implementation).
100 *
101 * You can manually specify which flavour you want. If you don't define
102 * any of these, libcoro tries to choose a safe and fast default:
50 * 103 *
51 * -DCORO_UCONTEXT 104 * -DCORO_UCONTEXT
52 * 105 *
53 * This flavour uses SUSv2's get/set/swap/makecontext functions that 106 * This flavour uses SUSv2's get/set/swap/makecontext functions that
54 * unfortunately only newer unices support. 107 * unfortunately only some unices support, and is quite slow.
55 * Use this for GNU/Linux + glibc-2.2.3.
56 * 108 *
57 * -DCORO_SJLJ 109 * -DCORO_SJLJ
58 * 110 *
59 * This flavour uses SUSv'2 setjmp/longjmp and sigaltstack functions to 111 * This flavour uses SUSv2's setjmp/longjmp and sigaltstack functions to
60 * do it's job. Coroutine creation is much slower than UCONTEXT, but 112 * do it's job. Coroutine creation is much slower than UCONTEXT, but
61 * context switching is often a bit cheaper. It should work on almost 113 * context switching is a bit cheaper. It should work on almost all unices.
62 * all unices. Use this for GNU/Linux + glibc-2.2. glibc-2.1 and below
63 * do not work with any sane model (neither sigaltstack nor context
64 * functions are implemented)
65 * 114 *
66 * -DCORO_LINUX 115 * -DCORO_LINUX
67 * 116 *
117 * CORO_SJLJ variant.
68 * Old GNU/Linux systems (<= glibc-2.1) work with this implementation 118 * Old GNU/Linux systems (<= glibc-2.1) only work with this implementation
69 * (very fast). 119 * (it is very fast and therefore recommended over other methods, but
120 * doesn't work with anything newer).
70 * 121 *
71 * -DCORO_LOOSE 122 * -DCORO_LOSER
72 * 123 *
124 * CORO_SJLJ variant.
73 * Microsoft's highly proprietary platform doesn't support sigaltstack, and 125 * Microsoft's highly proprietary platform doesn't support sigaltstack, and
74 * this automatically selects a suitable workaround for this platform. 126 * this selects a suitable workaround for this platform. It might not work
75 * (untested) 127 * with your compiler though - it has only been tested with MSVC 6.
128 *
129 * -DCORO_FIBER
130 *
131 * Slower, but probably more portable variant for the Microsoft operating
132 * system, using fibers. Ignores the passed stack and allocates it internally.
133 * Also, due to bugs in cygwin, this does not work with cygwin.
76 * 134 *
77 * -DCORO_IRIX 135 * -DCORO_IRIX
78 * 136 *
137 * CORO_SJLJ variant.
79 * SGI's version of Microsoft's NT ;) 138 * For SGI's version of Microsoft's NT ;)
139 *
140 * -DCORO_ASM
141 *
142 * Hand coded assembly, known to work only on a few architectures/ABI:
143 * GCC + x86/IA32 and amd64/x86_64 + GNU/Linux and a few BSDs. Fastest choice,
144 * if it works.
145 *
146 * -DCORO_PTHREAD
147 *
148 * Use the pthread API. You have to provide <pthread.h> and -lpthread.
149 * This is likely the slowest backend, and it also does not support fork(),
150 * so avoid it at all costs.
80 * 151 *
81 * If you define neither of these symbols, coro.h will try to autodetect 152 * If you define neither of these symbols, coro.h will try to autodetect
82 * the model. This currently works for CORO_LOOSE only. For the other 153 * the best/safest model. To help with the autodetection, you should check
83 * alternatives you should check (e.g. using autoconf) and define the 154 * (e.g. using autoconf) and define the following symbols: HAVE_UCONTEXT_H
84 * following symbols: HAVE_UCONTEXT_H / HAVE_SETJMP_H / HAVE_SIGALTSTACK. 155 * / HAVE_SETJMP_H / HAVE_SIGALTSTACK.
156 */
157
158/*
159 * Changes when the API changes incompatibly.
160 * This is ONLY the API version - there is no ABI compatibility between releases.
85 */ 161 *
162 * Changes in API version 2:
163 * replaced bogus -DCORO_LOOSE with grammatically more correct -DCORO_LOSER
164 * Changes in API version 3:
165 * introduced stack management (CORO_STACKALLOC)
166 */
167#define CORO_VERSION 3
168
169#include <stddef.h>
86 170
87/* 171/*
88 * This is the type for the initialization function of a new coroutine. 172 * This is the type for the initialization function of a new coroutine.
89 */ 173 */
90typedef void (*coro_func)(void *); 174typedef void (*coro_func)(void *);
91 175
92/* 176/*
93 * A coroutine state is saved in the following structure. Treat it as a 177 * A coroutine state is saved in the following structure. Treat it as an
94 * opaque type. errno and sigmask might be saved, but don't rely on it, 178 * opaque type. errno and sigmask might be saved, but don't rely on it,
95 * implement your own switching primitive. 179 * implement your own switching primitive if you need that.
96 */ 180 */
97typedef struct coro_context coro_context; 181typedef struct coro_context coro_context;
98 182
99/* 183/*
100 * This function creates a new coroutine. Apart from a pointer to an 184 * This function creates a new coroutine. Apart from a pointer to an
101 * uninitialized coro_context, it expects a pointer to the entry function 185 * uninitialised coro_context, it expects a pointer to the entry function
102 * and the single pointer value that is given to it as argument. 186 * and the single pointer value that is given to it as argument.
103 * 187 *
104 * Allocating/deallocating the stack is your own responsibility, so there is 188 * Allocating/deallocating the stack is your own responsibility.
105 * no coro_destroy function.
106 */ 189 *
107void coro_create (coro_context *ctx, 190 * As a special case, if coro, arg, sptr and ssze are all zero,
108 coro_func coro, void *arg, 191 * then an "empty" coro_context will be created that is suitable
109 void *sptr, long ssize); 192 * as an initial source for coro_transfer.
193 *
194 * This function is not reentrant, but putting a mutex around it
195 * will work.
196 */
197void coro_create (coro_context *ctx, /* an uninitialised coro_context */
198 coro_func coro, /* the coroutine code to be executed */
199 void *arg, /* a single pointer passed to the coro */
200 void *sptr, /* start of stack area */
201 size_t ssze); /* size of stack area in bytes */
110 202
111/* 203/*
112 * The following prototype defines the coroutine switching function. It is 204 * The following prototype defines the coroutine switching function. It is
113 * usually implemented as a macro, so watch out. 205 * sometimes implemented as a macro, so watch out.
206 *
207 * This function is thread-safe and reentrant.
114 * 208 */
209#if 0
115void coro_transfer(coro_context *prev, coro_context *next); 210void coro_transfer (coro_context *prev, coro_context *next);
211#endif
212
213/*
214 * The following prototype defines the coroutine destroy function. It
215 * is sometimes implemented as a macro, so watch out. It also serves no
216 * purpose unless you want to use the CORO_PTHREAD backend, where it is
217 * used to clean up the thread. You are responsible for freeing the stack
218 * and the context itself.
116 */ 219 *
117 220 * This function is thread-safe and reentrant.
118/*
119 * That was it. No other user-visible functions are implemented here.
120 */ 221 */
222#if 0
223void coro_destroy (coro_context *ctx);
224#endif
121 225
122/*****************************************************************************/ 226/*****************************************************************************/
227/* optional stack management */
228/*****************************************************************************/
229/*
230 * You can disable all of the stack management functions by
231 * defining CORO_STACKALLOC to 0. Otherwise, they are enabled by default.
232 *
233 * If stack management is enabled, you can influence the implementation via these
234 * symbols:
235 *
236 * -DCORO_USE_VALGRIND
237 *
238 * If defined, then libcoro will include valgrind/valgrind.h and register
239 * and unregister stacks with valgrind.
240 *
241 * -DCORO_GUARDPAGES=n
242 *
243 * libcoro will try to use the specified number of guard pages to protect against
244 * stack overflow. If n is 0, then the feature will be disabled. If it isn't
245 * defined, then libcoro will choose a suitable default. If guardpages are not
246 * supported on the platform, then the feature will be silently disabled.
247 */
248#ifndef CORO_STACKALLOC
249# define CORO_STACKALLOC 1
250#endif
123 251
252#if CORO_STACKALLOC
253
254/*
255 * The only allowed operations on these struct members is to read the
256 * "sptr" and "ssze" members to pass it to coro_create, to read the "sptr"
257 * member to see if it is false, in which case the stack isn't allocated,
258 * and to set the "sptr" member to 0, to indicate to coro_stack_free to
259 * not actually do anything.
260 */
261
262struct coro_stack
263{
264 void *sptr;
265 size_t ssze;
266#if CORO_USE_VALGRIND
267 int valgrind_id;
268#endif
269};
270
271/*
272 * Try to allocate a stack of at least the given size and return true if
273 * successful, or false otherwise.
274 *
275 * The size is *NOT* specified in bytes, but in units of sizeof (void *),
276 * i.e. the stack is typically 4(8) times larger on 32 bit(64 bit) platforms
277 * then the size passed in.
278 *
279 * If size is 0, then a "suitable" stack size is chosen (usually 1-2MB).
280 */
281int coro_stack_alloc (struct coro_stack *stack, unsigned int size);
282
283/*
284 * Free the stack allocated by coro_stack_alloc again. It is safe to
285 * call this function on the coro_stack structure even if coro_stack_alloc
286 * failed.
287 */
288void coro_stack_free (struct coro_stack *stack);
289
290#endif
291
292/*
293 * That was it. No other user-serviceable parts below here.
294 */
295
296/*****************************************************************************/
297
124#if !defined(CORO_LOOSE) && !defined(CORO_UCONTEXT) \ 298#if !defined CORO_LOSER && !defined CORO_UCONTEXT \
125 && !defined(CORO_SJLJ) && !defined(CORO_LINUX) \ 299 && !defined CORO_SJLJ && !defined CORO_LINUX \
126 && !defined(CORO_IRIX) 300 && !defined CORO_IRIX && !defined CORO_ASM \
127# if defined(WINDOWS) 301 && !defined CORO_PTHREAD && !defined CORO_FIBER
302# if defined WINDOWS && (defined __i386 || (__x86_64 || defined _M_IX86 || defined _M_AMD64)
303# define CORO_ASM 1
304# elif defined WINDOWS || defined _WIN32
128# define CORO_LOOSE 1 /* you don't win with windoze */ 305# define CORO_LOSER 1 /* you don't win with windoze */
129# elif defined(__linux) && defined(__x86) 306# elif __linux && (__i386 || (__x86_64 && !__ILP32))
307# define CORO_ASM 1
130# elif defined(HAVE_UCONTEXT_H) 308# elif defined HAVE_UCONTEXT_H
131# define CORO_UCONTEXT 1 309# define CORO_UCONTEXT 1
132# elif defined(HAVE_SETJMP_H) && defined(HAVE_SIGALTSTACK) 310# elif defined HAVE_SETJMP_H && defined HAVE_SIGALTSTACK
133# define CORO_SJLJ 1 311# define CORO_SJLJ 1
134# else 312# else
135error unknown or unsupported architecture 313error unknown or unsupported architecture
136# endif 314# endif
137#endif 315#endif
138 316
139/*****************************************************************************/ 317/*****************************************************************************/
140 318
141#if CORO_UCONTEXT 319#if CORO_UCONTEXT
142 320
143#include <ucontext.h> 321# include <ucontext.h>
144 322
145struct coro_context { 323struct coro_context
324{
146 ucontext_t uc; 325 ucontext_t uc;
147}; 326};
148 327
149#define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc)) 328# define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc))
329# define coro_destroy(ctx) (void *)(ctx)
150 330
151#elif CORO_SJLJ || CORO_LOOSE || CORO_LINUX || CORO_IRIX 331#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX
152 332
153#ifdef CORO_LINUX 333# if defined(CORO_LINUX) && !defined(_GNU_SOURCE)
154# define _GNU_SOURCE // for linux libc 334# define _GNU_SOURCE /* for glibc */
155#endif 335# endif
156 336
337# if !CORO_LOSER
338# include <unistd.h>
339# endif
340
341/* solaris is hopelessly borked, it expands _XOPEN_UNIX to nothing */
342# if __sun
343# undef _XOPEN_UNIX
344# define _XOPEN_UNIX 1
345# endif
346
157#include <setjmp.h> 347# include <setjmp.h>
158 348
349# if _XOPEN_UNIX > 0 || defined (_setjmp)
350# define coro_jmp_buf jmp_buf
351# define coro_setjmp(env) _setjmp (env)
352# define coro_longjmp(env) _longjmp ((env), 1)
353# elif CORO_LOSER
354# define coro_jmp_buf jmp_buf
355# define coro_setjmp(env) setjmp (env)
356# define coro_longjmp(env) longjmp ((env), 1)
357# else
358# define coro_jmp_buf sigjmp_buf
359# define coro_setjmp(env) sigsetjmp (env, 0)
360# define coro_longjmp(env) siglongjmp ((env), 1)
361# endif
362
159struct coro_context { 363struct coro_context
364{
160 jmp_buf env; 365 coro_jmp_buf env;
161}; 366};
162 367
163#define coro_transfer(p,n) do { if (!setjmp ((p)->env)) longjmp ((n)->env, 1); } while(0) 368# define coro_transfer(p,n) do { if (!coro_setjmp ((p)->env)) coro_longjmp ((n)->env); } while (0)
369# define coro_destroy(ctx) (void *)(ctx)
164 370
165#endif 371#elif CORO_ASM
166 372
167#endif 373struct coro_context
374{
375 void **sp; /* must be at offset 0 */
376};
168 377
378void __attribute__ ((__noinline__, __regparm__(2)))
379coro_transfer (coro_context *prev, coro_context *next);
380
381# define coro_destroy(ctx) (void *)(ctx)
382
383#elif CORO_PTHREAD
384
385# include <pthread.h>
386
387extern pthread_mutex_t coro_mutex;
388
389struct coro_context
390{
391 pthread_cond_t cv;
392 pthread_t id;
393};
394
395void coro_transfer (coro_context *prev, coro_context *next);
396void coro_destroy (coro_context *ctx);
397
398#elif CORO_FIBER
399
400struct coro_context
401{
402 void *fiber;
403 /* only used for initialisation */
404 coro_func coro;
405 void *arg;
406};
407
408void coro_transfer (coro_context *prev, coro_context *next);
409void coro_destroy (coro_context *ctx);
410
411#endif
412
413#if __cplusplus
414}
415#endif
416
417#endif
418

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