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Comparing libcoro/coro.h (file contents):
Revision 1.32 by root, Fri Nov 7 20:12:26 2008 UTC vs.
Revision 1.55 by root, Sun Mar 6 06:26:21 2016 UTC

1/* 1/*
2 * Copyright (c) 2001-2008 Marc Alexander Lehmann <schmorp@schmorp.de> 2 * Copyright (c) 2001-2012,2015 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,
… …
60 * 2008-11-05 Hopefully fix misaligned stacks with CORO_ASM/SETJMP. 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. 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. 62 * introduce coro_destroy, which is a nop except for pthreads.
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.
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 * 2015-12-05 experimental asm be for arm7, based on a patch by Nick Zavaritsky.
83 * use __name__ for predefined symbols, as in libecb.
84 * enable guard pages on arm, aarch64 and mips.
65 */ 85 */
66 86
67#ifndef CORO_H 87#ifndef CORO_H
68#define CORO_H 88#define CORO_H
69 89
70#define CORO_VERSION 2 90#if __cplusplus
71 91extern "C" {
72/* 92#endif
73 * Changes since API version 1:
74 * replaced bogus -DCORO_LOOSE with gramatically more correct -DCORO_LOSER
75 */
76 93
77/* 94/*
78 * This library consists of only three files 95 * This library consists of only three files
79 * coro.h, coro.c and LICENSE (and optionally README) 96 * coro.h, coro.c and LICENSE (and optionally README)
80 * 97 *
81 * It implements what is known as coroutines, in a hopefully 98 * It implements what is known as coroutines, in a hopefully
82 * portable way. At the moment you have to define which kind 99 * portable way.
83 * of implementation flavour you want: 100 *
101 * All compiletime symbols must be defined both when including coro.h
102 * (using libcoro) as well as when compiling coro.c (the implementation).
103 *
104 * You can manually specify which flavour you want. If you don't define
105 * any of these, libcoro tries to choose a safe and fast default:
84 * 106 *
85 * -DCORO_UCONTEXT 107 * -DCORO_UCONTEXT
86 * 108 *
87 * This flavour uses SUSv2's get/set/swap/makecontext functions that 109 * This flavour uses SUSv2's get/set/swap/makecontext functions that
88 * unfortunately only newer unices support. 110 * unfortunately only some unices support, and is quite slow.
89 * 111 *
90 * -DCORO_SJLJ 112 * -DCORO_SJLJ
91 * 113 *
92 * This flavour uses SUSv2's setjmp/longjmp and sigaltstack functions to 114 * This flavour uses SUSv2's setjmp/longjmp and sigaltstack functions to
93 * do it's job. Coroutine creation is much slower than UCONTEXT, but 115 * do it's job. Coroutine creation is much slower than UCONTEXT, but
94 * context switching is often a bit cheaper. It should work on almost 116 * context switching is a bit cheaper. It should work on almost all unices.
95 * all unices.
96 * 117 *
97 * -DCORO_LINUX 118 * -DCORO_LINUX
98 * 119 *
120 * CORO_SJLJ variant.
99 * Old GNU/Linux systems (<= glibc-2.1) only work with this implementation 121 * Old GNU/Linux systems (<= glibc-2.1) only work with this implementation
100 * (it is very fast and therefore recommended over other methods, but 122 * (it is very fast and therefore recommended over other methods, but
101 * doesn't work with anything newer). 123 * doesn't work with anything newer).
102 * 124 *
103 * -DCORO_LOSER 125 * -DCORO_LOSER
104 * 126 *
127 * CORO_SJLJ variant.
105 * Microsoft's highly proprietary platform doesn't support sigaltstack, and 128 * Microsoft's highly proprietary platform doesn't support sigaltstack, and
106 * this automatically selects a suitable workaround for this platform. 129 * this selects a suitable workaround for this platform. It might not work
107 * (untested) 130 * with your compiler though - it has only been tested with MSVC 6.
131 *
132 * -DCORO_FIBER
133 *
134 * Slower, but probably more portable variant for the Microsoft operating
135 * system, using fibers. Ignores the passed stack and allocates it internally.
136 * Also, due to bugs in cygwin, this does not work with cygwin.
108 * 137 *
109 * -DCORO_IRIX 138 * -DCORO_IRIX
110 * 139 *
140 * CORO_SJLJ variant.
111 * SGI's version of Microsoft's NT ;) 141 * For SGI's version of Microsoft's NT ;)
112 * 142 *
113 * -DCORO_ASM 143 * -DCORO_ASM
114 * 144 *
115 * Handcoded assembly, known to work only on a few architectures/ABI: 145 * Hand coded assembly, known to work only on a few architectures/ABI:
116 * ELF Linux x86 && amd64 when gcc is used and optimisation is turned on. 146 * GCC + arm7/x86/IA32/amd64/x86_64 + GNU/Linux and a few BSDs. Fastest
147 * choice, if it works.
117 * 148 *
118 * -DCORO_PTHREAD 149 * -DCORO_PTHREAD
119 * 150 *
120 * Use the pthread API. You have to provide <pthread.h> and -lpthread. 151 * Use the pthread API. You have to provide <pthread.h> and -lpthread.
152 * This is likely the slowest backend, and it also does not support fork(),
153 * so avoid it at all costs.
121 * 154 *
122 * If you define neither of these symbols, coro.h will try to autodetect 155 * If you define neither of these symbols, coro.h will try to autodetect
123 * the model. This currently works for CORO_LOSER only. For the other 156 * the best/safest model. To help with the autodetection, you should check
124 * alternatives you should check (e.g. using autoconf) and define the 157 * (e.g. using autoconf) and define the following symbols: HAVE_UCONTEXT_H
125 * following symbols: HAVE_UCONTEXT_H / HAVE_SETJMP_H / HAVE_SIGALTSTACK. 158 * / HAVE_SETJMP_H / HAVE_SIGALTSTACK.
159 */
160
161/*
162 * Changes when the API changes incompatibly.
163 * This is ONLY the API version - there is no ABI compatibility between releases.
126 */ 164 *
165 * Changes in API version 2:
166 * replaced bogus -DCORO_LOOSE with grammatically more correct -DCORO_LOSER
167 * Changes in API version 3:
168 * introduced stack management (CORO_STACKALLOC)
169 */
170#define CORO_VERSION 3
171
172#include <stddef.h>
127 173
128/* 174/*
129 * This is the type for the initialization function of a new coroutine. 175 * This is the type for the initialization function of a new coroutine.
130 */ 176 */
131typedef void (*coro_func)(void *); 177typedef void (*coro_func)(void *);
… …
142 * uninitialised coro_context, it expects a pointer to the entry function 188 * uninitialised coro_context, it expects a pointer to the entry function
143 * and the single pointer value that is given to it as argument. 189 * and the single pointer value that is given to it as argument.
144 * 190 *
145 * Allocating/deallocating the stack is your own responsibility. 191 * Allocating/deallocating the stack is your own responsibility.
146 * 192 *
147 * As a special case, if coro, arg, sptr and ssize are all zero, 193 * As a special case, if coro, arg, sptr and ssze are all zero,
148 * then an "empty" coro_contetx will be created that is suitable 194 * then an "empty" coro_context will be created that is suitable
149 * as an initial source for coro_transfer. 195 * as an initial source for coro_transfer.
150 * 196 *
151 * This function is not reentrant, but putting a mutex around it 197 * This function is not reentrant, but putting a mutex around it
152 * will work. 198 * will work.
153 */ 199 */
154void coro_create (coro_context *ctx, /* an uninitialised coro_context */ 200void coro_create (coro_context *ctx, /* an uninitialised coro_context */
155 coro_func coro, /* the coroutine code to be executed */ 201 coro_func coro, /* the coroutine code to be executed */
156 void *arg, /* a single pointer passed to the coro */ 202 void *arg, /* a single pointer passed to the coro */
157 void *sptr, /* start of stack area */ 203 void *sptr, /* start of stack area */
158 long ssize); /* size of stack area */ 204 size_t ssze); /* size of stack area in bytes */
159 205
160/* 206/*
161 * The following prototype defines the coroutine switching function. It is 207 * The following prototype defines the coroutine switching function. It is
162 * usually implemented as a macro, so watch out. 208 * sometimes implemented as a macro, so watch out.
163 * 209 *
164 * This function is thread-safe and reentrant. 210 * This function is thread-safe and reentrant.
165 */ 211 */
166#if 0 212#if 0
167void coro_transfer (coro_context *prev, coro_context *next); 213void coro_transfer (coro_context *prev, coro_context *next);
168#endif 214#endif
169 215
170/* 216/*
171 * The following prototype defines the coroutine destroy function. It is 217 * The following prototype defines the coroutine destroy function. It
172 * usually implemented as a macro, so watch out. It also serves 218 * is sometimes implemented as a macro, so watch out. It also serves no
173 * no purpose unless you want to use the CORO_PTHREAD backend. 219 * purpose unless you want to use the CORO_PTHREAD backend, where it is
220 * used to clean up the thread. You are responsible for freeing the stack
221 * and the context itself.
174 * 222 *
175 * This function is thread-safe and reentrant. 223 * This function is thread-safe and reentrant.
176 */ 224 */
177#if 0 225#if 0
178void coro_destroy (coro_context *ctx); 226void coro_destroy (coro_context *ctx);
179#endif 227#endif
180 228
181/*
182 * That was it. No other user-visible functions are implemented here.
183 */
184
185/*****************************************************************************/ 229/*****************************************************************************/
230/* optional stack management */
231/*****************************************************************************/
232/*
233 * You can disable all of the stack management functions by
234 * defining CORO_STACKALLOC to 0. Otherwise, they are enabled by default.
235 *
236 * If stack management is enabled, you can influence the implementation via these
237 * symbols:
238 *
239 * -DCORO_USE_VALGRIND
240 *
241 * If defined, then libcoro will include valgrind/valgrind.h and register
242 * and unregister stacks with valgrind.
243 *
244 * -DCORO_GUARDPAGES=n
245 *
246 * libcoro will try to use the specified number of guard pages to protect against
247 * stack overflow. If n is 0, then the feature will be disabled. If it isn't
248 * defined, then libcoro will choose a suitable default. If guardpages are not
249 * supported on the platform, then the feature will be silently disabled.
250 */
251#ifndef CORO_STACKALLOC
252# define CORO_STACKALLOC 1
253#endif
186 254
255#if CORO_STACKALLOC
256
257/*
258 * The only allowed operations on these struct members is to read the
259 * "sptr" and "ssze" members to pass it to coro_create, to read the "sptr"
260 * member to see if it is false, in which case the stack isn't allocated,
261 * and to set the "sptr" member to 0, to indicate to coro_stack_free to
262 * not actually do anything.
263 */
264
265struct coro_stack
266{
267 void *sptr;
268 size_t ssze;
269#if CORO_USE_VALGRIND
270 int valgrind_id;
271#endif
272};
273
274/*
275 * Try to allocate a stack of at least the given size and return true if
276 * successful, or false otherwise.
277 *
278 * The size is *NOT* specified in bytes, but in units of sizeof (void *),
279 * i.e. the stack is typically 4(8) times larger on 32 bit(64 bit) platforms
280 * then the size passed in.
281 *
282 * If size is 0, then a "suitable" stack size is chosen (usually 1-2MB).
283 */
284int coro_stack_alloc (struct coro_stack *stack, unsigned int size);
285
286/*
287 * Free the stack allocated by coro_stack_alloc again. It is safe to
288 * call this function on the coro_stack structure even if coro_stack_alloc
289 * failed.
290 */
291void coro_stack_free (struct coro_stack *stack);
292
293#endif
294
295/*
296 * That was it. No other user-serviceable parts below here.
297 */
298
299/*****************************************************************************/
300
187#if !defined(CORO_LOSER) && !defined(CORO_UCONTEXT) \ 301#if !defined CORO_LOSER && !defined CORO_UCONTEXT \
188 && !defined(CORO_SJLJ) && !defined(CORO_LINUX) \ 302 && !defined CORO_SJLJ && !defined CORO_LINUX \
189 && !defined(CORO_IRIX) && !defined(CORO_ASM) \ 303 && !defined CORO_IRIX && !defined CORO_ASM \
190 && !defined(CORO_PTHREAD) 304 && !defined CORO_PTHREAD && !defined CORO_FIBER
191# if defined(WINDOWS) 305# if defined WINDOWS && (defined __i386__ || (__x86_64__ || defined _M_IX86 || defined _M_AMD64)
306# define CORO_ASM 1
307# elif defined WINDOWS || defined _WIN32
192# define CORO_LOSER 1 /* you don't win with windoze */ 308# define CORO_LOSER 1 /* you don't win with windoze */
193# elif defined(__linux) && (defined(__x86) || defined (__amd64)) 309# elif __linux && (__i386__ || (__x86_64__ && !__ILP32__) || (__arm__ && __ARCH_ARCH == 7))
194# define CORO_ASM 1 310# define CORO_ASM 1
195# elif defined(HAVE_UCONTEXT_H) 311# elif defined HAVE_UCONTEXT_H
196# define CORO_UCONTEXT 1 312# define CORO_UCONTEXT 1
197# elif defined(HAVE_SETJMP_H) && defined(HAVE_SIGALTSTACK) 313# elif defined HAVE_SETJMP_H && defined HAVE_SIGALTSTACK
198# define CORO_SJLJ 1 314# define CORO_SJLJ 1
199# else 315# else
200error unknown or unsupported architecture 316error unknown or unsupported architecture
201# endif 317# endif
202#endif 318#endif
… …
205 321
206#if CORO_UCONTEXT 322#if CORO_UCONTEXT
207 323
208# include <ucontext.h> 324# include <ucontext.h>
209 325
210struct coro_context { 326struct coro_context
327{
211 ucontext_t uc; 328 ucontext_t uc;
212}; 329};
213 330
214# define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc)) 331# define coro_transfer(p,n) swapcontext (&((p)->uc), &((n)->uc))
215# define coro_destroy(ctx) (void *)(ctx) 332# define coro_destroy(ctx) (void *)(ctx)
216 333
217#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX 334#elif CORO_SJLJ || CORO_LOSER || CORO_LINUX || CORO_IRIX
218 335
219# if defined(CORO_LINUX) && !defined(_GNU_SOURCE) 336# if defined(CORO_LINUX) && !defined(_GNU_SOURCE)
220# define _GNU_SOURCE /* for linux libc */ 337# define _GNU_SOURCE /* for glibc */
221# endif 338# endif
222 339
340# if !CORO_LOSER
341# include <unistd.h>
342# endif
343
344/* solaris is hopelessly borked, it expands _XOPEN_UNIX to nothing */
345# if __sun
346# undef _XOPEN_UNIX
347# define _XOPEN_UNIX 1
348# endif
349
223# include <setjmp.h> 350# include <setjmp.h>
224 351
225struct coro_context { 352# if _XOPEN_UNIX > 0 || defined (_setjmp)
226 jmp_buf env; 353# define coro_jmp_buf jmp_buf
227}; 354# define coro_setjmp(env) _setjmp (env)
228 355# define coro_longjmp(env) _longjmp ((env), 1)
229# if CORO_LINUX || (_XOPEN_SOURCE >= 600) 356# elif CORO_LOSER
230# define coro_transfer(p,n) do { if (!_setjmp ((p)->env)) _longjmp ((n)->env, 1); } while (0) 357# define coro_jmp_buf jmp_buf
358# define coro_setjmp(env) setjmp (env)
359# define coro_longjmp(env) longjmp ((env), 1)
231# else 360# else
232# define coro_transfer(p,n) do { if (!setjmp ((p)->env)) longjmp ((n)->env, 1); } while (0) 361# define coro_jmp_buf sigjmp_buf
362# define coro_setjmp(env) sigsetjmp (env, 0)
363# define coro_longjmp(env) siglongjmp ((env), 1)
233# endif 364# endif
234 365
366struct coro_context
367{
368 coro_jmp_buf env;
369};
370
371# define coro_transfer(p,n) do { if (!coro_setjmp ((p)->env)) coro_longjmp ((n)->env); } while (0)
235# define coro_destroy(ctx) (void *)(ctx) 372# define coro_destroy(ctx) (void *)(ctx)
236 373
237#elif CORO_ASM 374#elif CORO_ASM
238 375
239struct coro_context { 376struct coro_context
377{
240 volatile void **sp; /* must be at offset 0 */ 378 void **sp; /* must be at offset 0 */
241}; 379};
242 380
381#if __i386__ || __x86_64__
243void __attribute__ ((__noinline__, __regparm__(2))) 382void __attribute__ ((__noinline__, __regparm__(2)))
383#else
384void __attribute__ ((__noinline__))
385#endif
244coro_transfer (coro_context *prev, coro_context *next); 386coro_transfer (coro_context *prev, coro_context *next);
245 387
246# define coro_destroy(ctx) (void *)(ctx) 388# define coro_destroy(ctx) (void *)(ctx)
247 389
248#elif CORO_PTHREAD 390#elif CORO_PTHREAD
249 391
250# include <pthread.h> 392# include <pthread.h>
251 393
252extern pthread_mutex_t coro_mutex; 394extern pthread_mutex_t coro_mutex;
253 395
254struct coro_context { 396struct coro_context
397{
255 pthread_cond_t cv; 398 pthread_cond_t cv;
256 pthread_t id; 399 pthread_t id;
257}; 400};
258 401
259void coro_transfer (coro_context *prev, coro_context *next); 402void coro_transfer (coro_context *prev, coro_context *next);
260void coro_destroy (coro_context *ctx); 403void coro_destroy (coro_context *ctx);
261 404
262#endif 405#elif CORO_FIBER
263 406
264#endif 407struct coro_context
408{
409 void *fiber;
410 /* only used for initialisation */
411 coro_func coro;
412 void *arg;
413};
265 414
415void coro_transfer (coro_context *prev, coro_context *next);
416void coro_destroy (coro_context *ctx);
417
418#endif
419
420#if __cplusplus
421}
422#endif
423
424#endif
425

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