mirror of
https://github.com/VCMP-SqMod/SqMod.git
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Add MariaDB Connector/C as a built-in alternative (v3.2.3).
This commit is contained in:
Sandu Liviu Catalin
726
vendor/MDBC/libmariadb/ma_context.c
vendored
Normal file
726
vendor/MDBC/libmariadb/ma_context.c
vendored
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@ -0,0 +1,726 @@
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/*
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Copyright 2011, 2012 Kristian Nielsen and Monty Program Ab
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2016 MariaDB Corporation AB
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This file is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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||||
Lesser General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this. If not, see <http://www.gnu.org/licenses/>.
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*/
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/*
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Implementation of async context spawning using Posix ucontext and
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swapcontext().
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*/
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#include "ma_global.h"
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#include "ma_string.h"
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#include "ma_context.h"
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#ifdef HAVE_VALGRIND
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#include <valgrind/valgrind.h>
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#endif
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#ifdef MY_CONTEXT_USE_UCONTEXT
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/*
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The makecontext() only allows to pass integers into the created context :-(
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We want to pass pointers, so we do it this kinda hackish way.
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Anyway, it should work everywhere, and at least it does not break strict
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aliasing.
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*/
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union pass_void_ptr_as_2_int {
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int a[2];
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void *p;
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};
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/*
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We use old-style function definition here, as this is passed to
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makecontext(). And the type of the makecontext() argument does not match
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the actual type (as the actual type can differ from call to call).
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*/
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static void
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my_context_spawn_internal(i0, i1)
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int i0, i1;
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{
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int err;
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struct my_context *c;
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union pass_void_ptr_as_2_int u;
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u.a[0]= i0;
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u.a[1]= i1;
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c= (struct my_context *)u.p;
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(*c->user_func)(c->user_data);
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c->active= 0;
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err= setcontext(&c->base_context);
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fprintf(stderr, "Aieie, setcontext() failed: %d (errno=%d)\n", err, errno);
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}
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int
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my_context_continue(struct my_context *c)
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{
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int err;
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if (!c->active)
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return 0;
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err= swapcontext(&c->base_context, &c->spawned_context);
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if (err)
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{
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fprintf(stderr, "Aieie, swapcontext() failed: %d (errno=%d)\n",
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err, errno);
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return -1;
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}
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return c->active;
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}
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int
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my_context_spawn(struct my_context *c, void (*f)(void *), void *d)
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{
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int err;
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union pass_void_ptr_as_2_int u;
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err= getcontext(&c->spawned_context);
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if (err)
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return -1;
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c->spawned_context.uc_stack.ss_sp= c->stack;
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c->spawned_context.uc_stack.ss_size= c->stack_size;
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c->spawned_context.uc_link= NULL;
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c->user_func= f;
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c->user_data= d;
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c->active= 1;
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u.p= c;
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makecontext(&c->spawned_context, my_context_spawn_internal, 2,
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u.a[0], u.a[1]);
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return my_context_continue(c);
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}
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int
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my_context_yield(struct my_context *c)
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{
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int err;
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if (!c->active)
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return -1;
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err= swapcontext(&c->spawned_context, &c->base_context);
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if (err)
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return -1;
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return 0;
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}
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int
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my_context_init(struct my_context *c, size_t stack_size)
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{
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#if SIZEOF_CHARP > SIZEOF_INT*2
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#error Error: Unable to store pointer in 2 ints on this architecture
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#endif
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memset(c, 0, sizeof(*c));
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if (!(c->stack= malloc(stack_size)))
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return -1; /* Out of memory */
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c->stack_size= stack_size;
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#ifdef HAVE_VALGRIND
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c->valgrind_stack_id=
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VALGRIND_STACK_REGISTER(c->stack, ((unsigned char *)(c->stack))+stack_size);
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#endif
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return 0;
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}
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void
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my_context_destroy(struct my_context *c)
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{
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if (c->stack)
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{
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#ifdef HAVE_VALGRIND
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VALGRIND_STACK_DEREGISTER(c->valgrind_stack_id);
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#endif
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free(c->stack);
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}
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}
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#endif /* MY_CONTEXT_USE_UCONTEXT */
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#ifdef MY_CONTEXT_USE_X86_64_GCC_ASM
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/*
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GCC-amd64 implementation of my_context.
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This is slightly optimized in the common case where we never yield
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(eg. fetch next row and it is already fully received in buffer). In this
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case we do not need to restore registers at return (though we still need to
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save them as we cannot know if we will yield or not in advance).
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*/
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#include <stdint.h>
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#include <stdlib.h>
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/*
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Layout of saved registers etc.
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Since this is accessed through gcc inline assembler, it is simpler to just
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use numbers than to try to define nice constants or structs.
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0 0 %rsp
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1 8 %rbp
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2 16 %rbx
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3 24 %r12
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4 32 %r13
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5 40 %r14
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6 48 %r15
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7 56 %rip for done
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8 64 %rip for yield/continue
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*/
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int
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my_context_spawn(struct my_context *c, void (*f)(void *), void *d)
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{
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int ret;
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/*
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There are 6 callee-save registers we need to save and restore when
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suspending and continuing, plus stack pointer %rsp and instruction pointer
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%rip.
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However, if we never suspend, the user-supplied function will in any case
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restore the 6 callee-save registers, so we can avoid restoring them in
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this case.
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*/
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__asm__ __volatile__
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(
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"movq %%rsp, (%[save])\n\t"
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"movq %[stack], %%rsp\n\t"
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#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 && !defined(__INTEL_COMPILER)
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/*
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This emits a DWARF DW_CFA_undefined directive to make the return address
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||||
undefined. This indicates that this is the top of the stack frame, and
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helps tools that use DWARF stack unwinding to obtain stack traces.
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(I use numeric constant to avoid a dependency on libdwarf includes).
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*/
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".cfi_escape 0x07, 16\n\t"
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#endif
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"movq %%rbp, 8(%[save])\n\t"
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"movq %%rbx, 16(%[save])\n\t"
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"movq %%r12, 24(%[save])\n\t"
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"movq %%r13, 32(%[save])\n\t"
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"movq %%r14, 40(%[save])\n\t"
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"movq %%r15, 48(%[save])\n\t"
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"leaq 1f(%%rip), %%rax\n\t"
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"leaq 2f(%%rip), %%rcx\n\t"
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"movq %%rax, 56(%[save])\n\t"
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"movq %%rcx, 64(%[save])\n\t"
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/*
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Constraint below puts the argument to the user function into %rdi, as
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needed for the calling convention.
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*/
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"callq *%[f]\n\t"
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"jmpq *56(%[save])\n"
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/*
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Come here when operation is done.
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We do not need to restore callee-save registers, as the called function
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will do this for us if needed.
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*/
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"1:\n\t"
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"movq (%[save]), %%rsp\n\t"
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"xorl %[ret], %[ret]\n\t"
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"jmp 3f\n"
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/* Come here when operation was suspended. */
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"2:\n\t"
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"movl $1, %[ret]\n"
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"3:\n"
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: [ret] "=a" (ret),
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[f] "+S" (f),
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/* Need this in %rdi to follow calling convention. */
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[d] "+D" (d)
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: [stack] "a" (c->stack_top),
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/* Need this in callee-save register to preserve in function call. */
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[save] "b" (&c->save[0])
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: "rcx", "rdx", "r8", "r9", "r10", "r11", "memory", "cc"
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);
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return ret;
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}
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int
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my_context_continue(struct my_context *c)
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{
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int ret;
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__asm__ __volatile__
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(
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"movq (%[save]), %%rax\n\t"
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"movq %%rsp, (%[save])\n\t"
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"movq %%rax, %%rsp\n\t"
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"movq 8(%[save]), %%rax\n\t"
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"movq %%rbp, 8(%[save])\n\t"
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"movq %%rax, %%rbp\n\t"
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"movq 24(%[save]), %%rax\n\t"
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"movq %%r12, 24(%[save])\n\t"
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"movq %%rax, %%r12\n\t"
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"movq 32(%[save]), %%rax\n\t"
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"movq %%r13, 32(%[save])\n\t"
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"movq %%rax, %%r13\n\t"
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"movq 40(%[save]), %%rax\n\t"
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"movq %%r14, 40(%[save])\n\t"
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"movq %%rax, %%r14\n\t"
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"movq 48(%[save]), %%rax\n\t"
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"movq %%r15, 48(%[save])\n\t"
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"movq %%rax, %%r15\n\t"
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"leaq 1f(%%rip), %%rax\n\t"
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"leaq 2f(%%rip), %%rcx\n\t"
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"movq %%rax, 56(%[save])\n\t"
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"movq 64(%[save]), %%rax\n\t"
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"movq %%rcx, 64(%[save])\n\t"
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"movq 16(%[save]), %%rcx\n\t"
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"movq %%rbx, 16(%[save])\n\t"
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"movq %%rcx, %%rbx\n\t"
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"jmpq *%%rax\n"
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/*
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Come here when operation is done.
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Be sure to use the same callee-save register for %[save] here and in
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my_context_spawn(), so we preserve the value correctly at this point.
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*/
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"1:\n\t"
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"movq (%[save]), %%rsp\n\t"
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"movq 8(%[save]), %%rbp\n\t"
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/* %rbx is preserved from my_context_spawn() in this case. */
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"movq 24(%[save]), %%r12\n\t"
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"movq 32(%[save]), %%r13\n\t"
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"movq 40(%[save]), %%r14\n\t"
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"movq 48(%[save]), %%r15\n\t"
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||||
"xorl %[ret], %[ret]\n\t"
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"jmp 3f\n"
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/* Come here when operation is suspended. */
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||||
"2:\n\t"
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"movl $1, %[ret]\n"
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||||
"3:\n"
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||||
: [ret] "=a" (ret)
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||||
: /* Need this in callee-save register to preserve in function call. */
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||||
[save] "b" (&c->save[0])
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||||
: "rcx", "rdx", "rsi", "rdi", "r8", "r9", "r10", "r11", "memory", "cc"
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);
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return ret;
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}
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int
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my_context_yield(struct my_context *c)
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||||
{
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uint64_t *save= &c->save[0];
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__asm__ __volatile__
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||||
(
|
||||
"movq (%[save]), %%rax\n\t"
|
||||
"movq %%rsp, (%[save])\n\t"
|
||||
"movq %%rax, %%rsp\n\t"
|
||||
"movq 8(%[save]), %%rax\n\t"
|
||||
"movq %%rbp, 8(%[save])\n\t"
|
||||
"movq %%rax, %%rbp\n\t"
|
||||
"movq 16(%[save]), %%rax\n\t"
|
||||
"movq %%rbx, 16(%[save])\n\t"
|
||||
"movq %%rax, %%rbx\n\t"
|
||||
"movq 24(%[save]), %%rax\n\t"
|
||||
"movq %%r12, 24(%[save])\n\t"
|
||||
"movq %%rax, %%r12\n\t"
|
||||
"movq 32(%[save]), %%rax\n\t"
|
||||
"movq %%r13, 32(%[save])\n\t"
|
||||
"movq %%rax, %%r13\n\t"
|
||||
"movq 40(%[save]), %%rax\n\t"
|
||||
"movq %%r14, 40(%[save])\n\t"
|
||||
"movq %%rax, %%r14\n\t"
|
||||
"movq 48(%[save]), %%rax\n\t"
|
||||
"movq %%r15, 48(%[save])\n\t"
|
||||
"movq %%rax, %%r15\n\t"
|
||||
"movq 64(%[save]), %%rax\n\t"
|
||||
"leaq 1f(%%rip), %%rcx\n\t"
|
||||
"movq %%rcx, 64(%[save])\n\t"
|
||||
|
||||
"jmpq *%%rax\n"
|
||||
|
||||
"1:\n"
|
||||
: [save] "+D" (save)
|
||||
:
|
||||
: "rax", "rcx", "rdx", "rsi", "r8", "r9", "r10", "r11", "memory", "cc"
|
||||
);
|
||||
return 0;
|
||||
}
|
||||
|
||||
int
|
||||
my_context_init(struct my_context *c, size_t stack_size)
|
||||
{
|
||||
memset(c, 0, sizeof(*c));
|
||||
|
||||
if (!(c->stack_bot= malloc(stack_size)))
|
||||
return -1; /* Out of memory */
|
||||
/*
|
||||
The x86_64 ABI specifies 16-byte stack alignment.
|
||||
Also put two zero words at the top of the stack.
|
||||
*/
|
||||
c->stack_top= (void *)
|
||||
(( ((intptr)c->stack_bot + stack_size) & ~(intptr)0xf) - 16);
|
||||
memset(c->stack_top, 0, 16);
|
||||
|
||||
#ifdef HAVE_VALGRIND
|
||||
c->valgrind_stack_id=
|
||||
VALGRIND_STACK_REGISTER(c->stack_bot, c->stack_top);
|
||||
#endif
|
||||
return 0;
|
||||
}
|
||||
|
||||
void
|
||||
my_context_destroy(struct my_context *c)
|
||||
{
|
||||
if (c->stack_bot)
|
||||
{
|
||||
free(c->stack_bot);
|
||||
#ifdef HAVE_VALGRIND
|
||||
VALGRIND_STACK_DEREGISTER(c->valgrind_stack_id);
|
||||
#endif
|
||||
}
|
||||
}
|
||||
|
||||
#endif /* MY_CONTEXT_USE_X86_64_GCC_ASM */
|
||||
|
||||
|
||||
#ifdef MY_CONTEXT_USE_I386_GCC_ASM
|
||||
/*
|
||||
GCC-i386 implementation of my_context.
|
||||
|
||||
This is slightly optimized in the common case where we never yield
|
||||
(eg. fetch next row and it is already fully received in buffer). In this
|
||||
case we do not need to restore registers at return (though we still need to
|
||||
save them as we cannot know if we will yield or not in advance).
|
||||
*/
|
||||
|
||||
#include <stdint.h>
|
||||
#include <stdlib.h>
|
||||
|
||||
/*
|
||||
Layout of saved registers etc.
|
||||
Since this is accessed through gcc inline assembler, it is simpler to just
|
||||
use numbers than to try to define nice constants or structs.
|
||||
|
||||
0 0 %esp
|
||||
1 4 %ebp
|
||||
2 8 %ebx
|
||||
3 12 %esi
|
||||
4 16 %edi
|
||||
5 20 %eip for done
|
||||
6 24 %eip for yield/continue
|
||||
*/
|
||||
|
||||
int
|
||||
my_context_spawn(struct my_context *c, void (*f)(void *), void *d)
|
||||
{
|
||||
int ret;
|
||||
|
||||
/*
|
||||
There are 4 callee-save registers we need to save and restore when
|
||||
suspending and continuing, plus stack pointer %esp and instruction pointer
|
||||
%eip.
|
||||
|
||||
However, if we never suspend, the user-supplied function will in any case
|
||||
restore the 4 callee-save registers, so we can avoid restoring them in
|
||||
this case.
|
||||
*/
|
||||
__asm__ __volatile__
|
||||
(
|
||||
"movl %%esp, (%[save])\n\t"
|
||||
"movl %[stack], %%esp\n\t"
|
||||
#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 4 && !defined(__INTEL_COMPILER)
|
||||
/*
|
||||
This emits a DWARF DW_CFA_undefined directive to make the return address
|
||||
undefined. This indicates that this is the top of the stack frame, and
|
||||
helps tools that use DWARF stack unwinding to obtain stack traces.
|
||||
(I use numeric constant to avoid a dependency on libdwarf includes).
|
||||
*/
|
||||
".cfi_escape 0x07, 8\n\t"
|
||||
#endif
|
||||
/* Push the parameter on the stack. */
|
||||
"pushl %[d]\n\t"
|
||||
"movl %%ebp, 4(%[save])\n\t"
|
||||
"movl %%ebx, 8(%[save])\n\t"
|
||||
"movl %%esi, 12(%[save])\n\t"
|
||||
"movl %%edi, 16(%[save])\n\t"
|
||||
/* Get label addresses in -fPIC-compatible way (no pc-relative on 32bit) */
|
||||
"call 1f\n"
|
||||
"1:\n\t"
|
||||
"popl %%eax\n\t"
|
||||
"addl $(2f-1b), %%eax\n\t"
|
||||
"movl %%eax, 20(%[save])\n\t"
|
||||
"addl $(3f-2f), %%eax\n\t"
|
||||
"movl %%eax, 24(%[save])\n\t"
|
||||
"call *%[f]\n\t"
|
||||
"jmp *20(%[save])\n"
|
||||
/*
|
||||
Come here when operation is done.
|
||||
We do not need to restore callee-save registers, as the called function
|
||||
will do this for us if needed.
|
||||
*/
|
||||
"2:\n\t"
|
||||
"movl (%[save]), %%esp\n\t"
|
||||
"xorl %[ret], %[ret]\n\t"
|
||||
"jmp 4f\n"
|
||||
/* Come here when operation was suspended. */
|
||||
"3:\n\t"
|
||||
"movl $1, %[ret]\n"
|
||||
"4:\n"
|
||||
: [ret] "=a" (ret),
|
||||
[f] "+c" (f),
|
||||
[d] "+d" (d)
|
||||
: [stack] "a" (c->stack_top),
|
||||
/* Need this in callee-save register to preserve across function call. */
|
||||
[save] "D" (&c->save[0])
|
||||
: "memory", "cc"
|
||||
);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
int
|
||||
my_context_continue(struct my_context *c)
|
||||
{
|
||||
int ret;
|
||||
|
||||
__asm__ __volatile__
|
||||
(
|
||||
"movl (%[save]), %%eax\n\t"
|
||||
"movl %%esp, (%[save])\n\t"
|
||||
"movl %%eax, %%esp\n\t"
|
||||
"movl 4(%[save]), %%eax\n\t"
|
||||
"movl %%ebp, 4(%[save])\n\t"
|
||||
"movl %%eax, %%ebp\n\t"
|
||||
"movl 8(%[save]), %%eax\n\t"
|
||||
"movl %%ebx, 8(%[save])\n\t"
|
||||
"movl %%eax, %%ebx\n\t"
|
||||
"movl 12(%[save]), %%eax\n\t"
|
||||
"movl %%esi, 12(%[save])\n\t"
|
||||
"movl %%eax, %%esi\n\t"
|
||||
|
||||
"movl 24(%[save]), %%eax\n\t"
|
||||
"call 1f\n"
|
||||
"1:\n\t"
|
||||
"popl %%ecx\n\t"
|
||||
"addl $(2f-1b), %%ecx\n\t"
|
||||
"movl %%ecx, 20(%[save])\n\t"
|
||||
"addl $(3f-2f), %%ecx\n\t"
|
||||
"movl %%ecx, 24(%[save])\n\t"
|
||||
|
||||
/* Must restore %edi last as it is also our %[save] register. */
|
||||
"movl 16(%[save]), %%ecx\n\t"
|
||||
"movl %%edi, 16(%[save])\n\t"
|
||||
"movl %%ecx, %%edi\n\t"
|
||||
|
||||
"jmp *%%eax\n"
|
||||
/*
|
||||
Come here when operation is done.
|
||||
Be sure to use the same callee-save register for %[save] here and in
|
||||
my_context_spawn(), so we preserve the value correctly at this point.
|
||||
*/
|
||||
"2:\n\t"
|
||||
"movl (%[save]), %%esp\n\t"
|
||||
"movl 4(%[save]), %%ebp\n\t"
|
||||
"movl 8(%[save]), %%ebx\n\t"
|
||||
"movl 12(%[save]), %%esi\n\t"
|
||||
"movl 16(%[save]), %%edi\n\t"
|
||||
"xorl %[ret], %[ret]\n\t"
|
||||
"jmp 4f\n"
|
||||
/* Come here when operation is suspended. */
|
||||
"3:\n\t"
|
||||
"movl $1, %[ret]\n"
|
||||
"4:\n"
|
||||
: [ret] "=a" (ret)
|
||||
: /* Need this in callee-save register to preserve in function call. */
|
||||
[save] "D" (&c->save[0])
|
||||
: "ecx", "edx", "memory", "cc"
|
||||
);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
int
|
||||
my_context_yield(struct my_context *c)
|
||||
{
|
||||
uint64_t *save= &c->save[0];
|
||||
__asm__ __volatile__
|
||||
(
|
||||
"movl (%[save]), %%eax\n\t"
|
||||
"movl %%esp, (%[save])\n\t"
|
||||
"movl %%eax, %%esp\n\t"
|
||||
"movl 4(%[save]), %%eax\n\t"
|
||||
"movl %%ebp, 4(%[save])\n\t"
|
||||
"movl %%eax, %%ebp\n\t"
|
||||
"movl 8(%[save]), %%eax\n\t"
|
||||
"movl %%ebx, 8(%[save])\n\t"
|
||||
"movl %%eax, %%ebx\n\t"
|
||||
"movl 12(%[save]), %%eax\n\t"
|
||||
"movl %%esi, 12(%[save])\n\t"
|
||||
"movl %%eax, %%esi\n\t"
|
||||
"movl 16(%[save]), %%eax\n\t"
|
||||
"movl %%edi, 16(%[save])\n\t"
|
||||
"movl %%eax, %%edi\n\t"
|
||||
|
||||
"movl 24(%[save]), %%eax\n\t"
|
||||
"call 1f\n"
|
||||
"1:\n\t"
|
||||
"popl %%ecx\n\t"
|
||||
"addl $(2f-1b), %%ecx\n\t"
|
||||
"movl %%ecx, 24(%[save])\n\t"
|
||||
|
||||
"jmp *%%eax\n"
|
||||
|
||||
"2:\n"
|
||||
: [save] "+d" (save)
|
||||
:
|
||||
: "eax", "ecx", "memory", "cc"
|
||||
);
|
||||
return 0;
|
||||
}
|
||||
|
||||
int
|
||||
my_context_init(struct my_context *c, size_t stack_size)
|
||||
{
|
||||
memset(c, 0, sizeof(*c));
|
||||
if (!(c->stack_bot= malloc(stack_size)))
|
||||
return -1; /* Out of memory */
|
||||
c->stack_top= (void *)
|
||||
(( ((intptr)c->stack_bot + stack_size) & ~(intptr)0xf) - 16);
|
||||
memset(c->stack_top, 0, 16);
|
||||
|
||||
#ifdef HAVE_VALGRIND
|
||||
c->valgrind_stack_id=
|
||||
VALGRIND_STACK_REGISTER(c->stack_bot, c->stack_top);
|
||||
#endif
|
||||
return 0;
|
||||
}
|
||||
|
||||
void
|
||||
my_context_destroy(struct my_context *c)
|
||||
{
|
||||
if (c->stack_bot)
|
||||
{
|
||||
free(c->stack_bot);
|
||||
#ifdef HAVE_VALGRIND
|
||||
VALGRIND_STACK_DEREGISTER(c->valgrind_stack_id);
|
||||
#endif
|
||||
}
|
||||
}
|
||||
|
||||
#endif /* MY_CONTEXT_USE_I386_GCC_ASM */
|
||||
|
||||
|
||||
#ifdef MY_CONTEXT_USE_WIN32_FIBERS
|
||||
int
|
||||
my_context_yield(struct my_context *c)
|
||||
{
|
||||
c->return_value= 1;
|
||||
SwitchToFiber(c->app_fiber);
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
static void WINAPI
|
||||
my_context_trampoline(void *p)
|
||||
{
|
||||
struct my_context *c= (struct my_context *)p;
|
||||
/*
|
||||
Reuse the Fiber by looping infinitely, each time we are scheduled we
|
||||
spawn the appropriate function and switch back when it is done.
|
||||
|
||||
This way we avoid the overhead of CreateFiber() for every asynchroneous
|
||||
operation.
|
||||
*/
|
||||
for(;;)
|
||||
{
|
||||
(*(c->user_func))(c->user_arg);
|
||||
c->return_value= 0;
|
||||
SwitchToFiber(c->app_fiber);
|
||||
}
|
||||
}
|
||||
|
||||
int
|
||||
my_context_init(struct my_context *c, size_t stack_size)
|
||||
{
|
||||
memset(c, 0, sizeof(*c));
|
||||
c->lib_fiber= CreateFiber(stack_size, my_context_trampoline, c);
|
||||
if (c->lib_fiber)
|
||||
return 0;
|
||||
return -1;
|
||||
}
|
||||
|
||||
void
|
||||
my_context_destroy(struct my_context *c)
|
||||
{
|
||||
if (c->lib_fiber)
|
||||
{
|
||||
DeleteFiber(c->lib_fiber);
|
||||
c->lib_fiber= NULL;
|
||||
}
|
||||
}
|
||||
|
||||
int
|
||||
my_context_spawn(struct my_context *c, void (*f)(void *), void *d)
|
||||
{
|
||||
c->user_func= f;
|
||||
c->user_arg= d;
|
||||
return my_context_continue(c);
|
||||
}
|
||||
|
||||
int
|
||||
my_context_continue(struct my_context *c)
|
||||
{
|
||||
void *current_fiber= IsThreadAFiber() ? GetCurrentFiber() : ConvertThreadToFiber(c);
|
||||
c->app_fiber= current_fiber;
|
||||
SwitchToFiber(c->lib_fiber);
|
||||
return c->return_value;
|
||||
}
|
||||
|
||||
#endif /* MY_CONTEXT_USE_WIN32_FIBERS */
|
||||
|
||||
#ifdef MY_CONTEXT_DISABLE
|
||||
int
|
||||
my_context_continue(struct my_context *c)
|
||||
{
|
||||
return -1;
|
||||
}
|
||||
|
||||
|
||||
int
|
||||
my_context_spawn(struct my_context *c, void (*f)(void *), void *d)
|
||||
{
|
||||
return -1;
|
||||
}
|
||||
|
||||
|
||||
int
|
||||
my_context_yield(struct my_context *c)
|
||||
{
|
||||
return -1;
|
||||
}
|
||||
|
||||
int
|
||||
my_context_init(struct my_context *c, size_t stack_size)
|
||||
{
|
||||
return -1; /* Out of memory */
|
||||
}
|
||||
|
||||
void
|
||||
my_context_destroy(struct my_context *c)
|
||||
{
|
||||
}
|
||||
|
||||
#endif
|
||||
Reference in New Issue
Block a user