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Comparing libcoro/coro.h (file contents):
Revision 1.34 by root, Sat Nov 8 04:52:01 2008 UTC vs.
Revision 1.54 by root, Fri Dec 21 04:48:17 2012 UTC

1/* 1/*
2 * Copyright (c) 2001-2008 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 * 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
15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- 15 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
16 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 16 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
17 * 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-
18 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 18 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
… …
63 * speed up CORO_PTHREAD. Do no longer leak threads either. 63 * speed up CORO_PTHREAD. Do no longer leak threads either.
64 * coro_create now allows one to create source coro_contexts. 64 * coro_create now allows one to create source coro_contexts.
65 * do not rely on makecontext passing a void * correctly. 65 * do not rely on makecontext passing a void * correctly.
66 * try harder to get _setjmp/_longjmp. 66 * try harder to get _setjmp/_longjmp.
67 * major code cleanup/restructuring. 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.
68 */ 82 */
69 83
70#ifndef CORO_H 84#ifndef CORO_H
71#define CORO_H 85#define CORO_H
72 86
73#define CORO_VERSION 2 87#if __cplusplus
74 88extern "C" {
75/* 89#endif
76 * Changes since API version 1:
77 * replaced bogus -DCORO_LOOSE with gramatically more correct -DCORO_LOSER
78 */
79 90
80/* 91/*
81 * This library consists of only three files 92 * This library consists of only three files
82 * coro.h, coro.c and LICENSE (and optionally README) 93 * coro.h, coro.c and LICENSE (and optionally README)
83 * 94 *
84 * It implements what is known as coroutines, in a hopefully 95 * It implements what is known as coroutines, in a hopefully
85 * portable way. At the moment you have to define which kind 96 * portable way.
86 * 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:
87 * 103 *
88 * -DCORO_UCONTEXT 104 * -DCORO_UCONTEXT
89 * 105 *
90 * This flavour uses SUSv2's get/set/swap/makecontext functions that 106 * This flavour uses SUSv2's get/set/swap/makecontext functions that
91 * unfortunately only newer unices support. 107 * unfortunately only some unices support, and is quite slow.
92 * 108 *
93 * -DCORO_SJLJ 109 * -DCORO_SJLJ
94 * 110 *
95 * This flavour uses SUSv2's setjmp/longjmp and sigaltstack functions to 111 * This flavour uses SUSv2's setjmp/longjmp and sigaltstack functions to
96 * 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
97 * 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.
98 * all unices.
99 * 114 *
100 * -DCORO_LINUX 115 * -DCORO_LINUX
101 * 116 *
117 * CORO_SJLJ variant.
102 * Old GNU/Linux systems (<= glibc-2.1) only work with this implementation 118 * Old GNU/Linux systems (<= glibc-2.1) only work with this implementation
103 * (it is very fast and therefore recommended over other methods, but 119 * (it is very fast and therefore recommended over other methods, but
104 * doesn't work with anything newer). 120 * doesn't work with anything newer).
105 * 121 *
106 * -DCORO_LOSER 122 * -DCORO_LOSER
107 * 123 *
124 * CORO_SJLJ variant.
108 * Microsoft's highly proprietary platform doesn't support sigaltstack, and 125 * Microsoft's highly proprietary platform doesn't support sigaltstack, and
109 * this automatically selects a suitable workaround for this platform. 126 * this selects a suitable workaround for this platform. It might not work
110 * (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.
111 * 134 *
112 * -DCORO_IRIX 135 * -DCORO_IRIX
113 * 136 *
137 * CORO_SJLJ variant.
114 * SGI's version of Microsoft's NT ;) 138 * For SGI's version of Microsoft's NT ;)
115 * 139 *
116 * -DCORO_ASM 140 * -DCORO_ASM
117 * 141 *
118 * Handcoded assembly, known to work only on a few architectures/ABI: 142 * Hand coded assembly, known to work only on a few architectures/ABI:
119 * ELF Linux x86 && amd64 when gcc is used and optimisation is turned on. 143 * GCC + x86/IA32 and amd64/x86_64 + GNU/Linux and a few BSDs. Fastest choice,
144 * if it works.
120 * 145 *
121 * -DCORO_PTHREAD 146 * -DCORO_PTHREAD
122 * 147 *
123 * Use the pthread API. You have to provide <pthread.h> and -lpthread. 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.
124 * 151 *
125 * 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
126 * the model. This currently works for CORO_LOSER only. For the other 153 * the best/safest model. To help with the autodetection, you should check
127 * alternatives you should check (e.g. using autoconf) and define the 154 * (e.g. using autoconf) and define the following symbols: HAVE_UCONTEXT_H
128 * 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.
129 */ 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>
130 170
131/* 171/*
132 * 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.
133 */ 173 */
134typedef void (*coro_func)(void *); 174typedef void (*coro_func)(void *);
… …
145 * uninitialised coro_context, it expects a pointer to the entry function 185 * uninitialised coro_context, it expects a pointer to the entry function
146 * 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.
147 * 187 *
148 * Allocating/deallocating the stack is your own responsibility. 188 * Allocating/deallocating the stack is your own responsibility.
149 * 189 *
150 * As a special case, if coro, arg, sptr and ssize are all zero, 190 * As a special case, if coro, arg, sptr and ssze are all zero,
151 * then an "empty" coro_contetx will be created that is suitable 191 * then an "empty" coro_context will be created that is suitable
152 * as an initial source for coro_transfer. 192 * as an initial source for coro_transfer.
153 * 193 *
154 * This function is not reentrant, but putting a mutex around it 194 * This function is not reentrant, but putting a mutex around it
155 * will work. 195 * will work.
156 */ 196 */
157void coro_create (coro_context *ctx, /* an uninitialised coro_context */ 197void coro_create (coro_context *ctx, /* an uninitialised coro_context */
158 coro_func coro, /* the coroutine code to be executed */ 198 coro_func coro, /* the coroutine code to be executed */
159 void *arg, /* a single pointer passed to the coro */ 199 void *arg, /* a single pointer passed to the coro */
160 void *sptr, /* start of stack area */ 200 void *sptr, /* start of stack area */
161 long ssize); /* size of stack area */ 201 size_t ssze); /* size of stack area in bytes */
162 202
163/* 203/*
164 * The following prototype defines the coroutine switching function. It is 204 * The following prototype defines the coroutine switching function. It is
165 * usually implemented as a macro, so watch out. 205 * sometimes implemented as a macro, so watch out.
166 * 206 *
167 * This function is thread-safe and reentrant. 207 * This function is thread-safe and reentrant.
168 */ 208 */
169#if 0 209#if 0
170void coro_transfer (coro_context *prev, coro_context *next); 210void coro_transfer (coro_context *prev, coro_context *next);
171#endif 211#endif
172 212
173/* 213/*
174 * The following prototype defines the coroutine destroy function. It is 214 * The following prototype defines the coroutine destroy function. It
175 * usually implemented as a macro, so watch out. It also serves 215 * is sometimes implemented as a macro, so watch out. It also serves no
176 * no purpose unless you want to use the CORO_PTHREAD backend. 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.
177 * 219 *
178 * This function is thread-safe and reentrant. 220 * This function is thread-safe and reentrant.
179 */ 221 */
180#if 0 222#if 0
181void coro_destroy (coro_context *ctx); 223void coro_destroy (coro_context *ctx);
182#endif 224#endif
183 225
184/*
185 * That was it. No other user-visible functions are implemented here.
186 */
187
188/*****************************************************************************/ 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
189 251
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
190#if !defined(CORO_LOSER) && !defined(CORO_UCONTEXT) \ 298#if !defined CORO_LOSER && !defined CORO_UCONTEXT \
191 && !defined(CORO_SJLJ) && !defined(CORO_LINUX) \ 299 && !defined CORO_SJLJ && !defined CORO_LINUX \
192 && !defined(CORO_IRIX) && !defined(CORO_ASM) \ 300 && !defined CORO_IRIX && !defined CORO_ASM \
193 && !defined(CORO_PTHREAD) 301 && !defined CORO_PTHREAD && !defined CORO_FIBER
194# if defined(WINDOWS) 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
195# define CORO_LOSER 1 /* you don't win with windoze */ 305# define CORO_LOSER 1 /* you don't win with windoze */
196# elif defined(__linux) && (defined(__x86) || defined (__amd64)) 306# elif __linux && (__i386 || (__x86_64 && !__ILP32))
197# define CORO_ASM 1 307# define CORO_ASM 1
198# elif defined(HAVE_UCONTEXT_H) 308# elif defined HAVE_UCONTEXT_H
199# define CORO_UCONTEXT 1 309# define CORO_UCONTEXT 1
200# elif defined(HAVE_SETJMP_H) && defined(HAVE_SIGALTSTACK) 310# elif defined HAVE_SETJMP_H && defined HAVE_SIGALTSTACK
201# define CORO_SJLJ 1 311# define CORO_SJLJ 1
202# else 312# else
203error unknown or unsupported architecture 313error unknown or unsupported architecture
204# endif 314# endif
205#endif 315#endif
… …
208 318
209#if CORO_UCONTEXT 319#if CORO_UCONTEXT
210 320
211# include <ucontext.h> 321# include <ucontext.h>
212 322
213struct coro_context { 323struct coro_context
324{
214 ucontext_t uc; 325 ucontext_t uc;
215}; 326};
216 327
217# define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc)) 328# define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc))
218# define coro_destroy(ctx) (void *)(ctx) 329# define coro_destroy(ctx) (void *)(ctx)
219 330
220#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX 331#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX
221 332
222# if defined(CORO_LINUX) && !defined(_GNU_SOURCE) 333# if defined(CORO_LINUX) && !defined(_GNU_SOURCE)
223# define _GNU_SOURCE /* for linux libc */ 334# define _GNU_SOURCE /* for glibc */
224# endif 335# endif
225 336
226# if !CORO_LOSER 337# if !CORO_LOSER
227# include <unistd.h> 338# include <unistd.h>
228# endif 339# endif
229 340
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
230# include <setjmp.h> 347# include <setjmp.h>
231 348
232struct coro_context { 349# if _XOPEN_UNIX > 0 || defined (_setjmp)
233 jmp_buf env; 350# define coro_jmp_buf jmp_buf
234}; 351# define coro_setjmp(env) _setjmp (env)
235 352# define coro_longjmp(env) _longjmp ((env), 1)
236# if _XOPEN_UNIX > 0
237# define coro_transfer(p,n) do { if (! _setjmp ((p)->env )) _longjmp ((n)->env, 1); } while (0)
238# elif CORO_LOSER 353# elif CORO_LOSER
239# define coro_transfer(p,n) do { if (! setjmp ((p)->env )) longjmp ((n)->env, 1); } while (0) 354# define coro_jmp_buf jmp_buf
355# define coro_setjmp(env) setjmp (env)
356# define coro_longjmp(env) longjmp ((env), 1)
240# else 357# else
241# define coro_transfer(p,n) do { if (!sigsetjmp ((p)->env, 0)) siglongjmp ((n)->env, 1); } while (0) 358# define coro_jmp_buf sigjmp_buf
359# define coro_setjmp(env) sigsetjmp (env, 0)
360# define coro_longjmp(env) siglongjmp ((env), 1)
242# endif 361# endif
243 362
363struct coro_context
364{
365 coro_jmp_buf env;
366};
367
368# define coro_transfer(p,n) do { if (!coro_setjmp ((p)->env)) coro_longjmp ((n)->env); } while (0)
244# define coro_destroy(ctx) (void *)(ctx) 369# define coro_destroy(ctx) (void *)(ctx)
245 370
246#elif CORO_ASM 371#elif CORO_ASM
247 372
248struct coro_context { 373struct coro_context
374{
249 void **sp; /* must be at offset 0 */ 375 void **sp; /* must be at offset 0 */
250}; 376};
251 377
252void __attribute__ ((__noinline__, __regparm__(2))) 378void __attribute__ ((__noinline__, __regparm__(2)))
253coro_transfer (coro_context *prev, coro_context *next); 379coro_transfer (coro_context *prev, coro_context *next);
… …
258 384
259# include <pthread.h> 385# include <pthread.h>
260 386
261extern pthread_mutex_t coro_mutex; 387extern pthread_mutex_t coro_mutex;
262 388
263struct coro_context { 389struct coro_context
390{
264 pthread_cond_t cv; 391 pthread_cond_t cv;
265 pthread_t id; 392 pthread_t id;
266}; 393};
267 394
268void coro_transfer (coro_context *prev, coro_context *next); 395void coro_transfer (coro_context *prev, coro_context *next);
269void coro_destroy (coro_context *ctx); 396void coro_destroy (coro_context *ctx);
270 397
271#endif 398#elif CORO_FIBER
272 399
273#endif 400struct coro_context
401{
402 void *fiber;
403 /* only used for initialisation */
404 coro_func coro;
405 void *arg;
406};
274 407
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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