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Diffstat (limited to 'trunk/src/lib/cothread/x86.c')
-rw-r--r--trunk/src/lib/cothread/x86.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/trunk/src/lib/cothread/x86.c b/trunk/src/lib/cothread/x86.c
new file mode 100644
index 00000000000..2d083995b3d
--- /dev/null
+++ b/trunk/src/lib/cothread/x86.c
@@ -0,0 +1,93 @@
+/*
+ libco.x86 (2009-10-12)
+ author: byuu
+ license: public domain
+*/
+
+#define LIBCO_C
+#include "libco.h"
+#include <assert.h>
+#include <stdlib.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if defined(_MSC_VER)
+ #define fastcall __fastcall
+#elif defined(__GNUC__)
+ #define fastcall __attribute__((fastcall))
+#else
+ #error "libco: please define fastcall macro"
+#endif
+
+static thread_local long co_active_buffer[64];
+static thread_local cothread_t co_active_handle = 0;
+static void (fastcall *co_swap)(cothread_t, cothread_t) = 0;
+
+//ABI: fastcall
+static unsigned char co_swap_function[] = {
+ 0x89, 0x22, 0x8B, 0x21, 0x58, 0x89, 0x6A, 0x04, 0x89, 0x72, 0x08, 0x89, 0x7A, 0x0C, 0x89, 0x5A,
+ 0x10, 0x8B, 0x69, 0x04, 0x8B, 0x71, 0x08, 0x8B, 0x79, 0x0C, 0x8B, 0x59, 0x10, 0xFF, 0xE0,
+};
+
+#ifdef _WIN32
+ #include <windows.h>
+
+ void co_init() {
+ DWORD old_privileges;
+ VirtualProtect(co_swap_function, sizeof co_swap_function, PAGE_EXECUTE_READWRITE, &old_privileges);
+ }
+#else
+ #include <unistd.h>
+ #include <sys/mman.h>
+
+ void co_init() {
+ unsigned long addr = (unsigned long)co_swap_function;
+ unsigned long base = addr - (addr % sysconf(_SC_PAGESIZE));
+ unsigned long size = (addr - base) + sizeof co_swap_function;
+ mprotect((void*)base, size, PROT_READ | PROT_WRITE | PROT_EXEC);
+ }
+#endif
+
+static void crash() {
+ assert(0); /* called only if cothread_t entrypoint returns */
+}
+
+cothread_t co_active() {
+ if(!co_active_handle) co_active_handle = &co_active_buffer;
+ return co_active_handle;
+}
+
+cothread_t co_create(unsigned int size, void (*entrypoint)(void)) {
+ cothread_t handle;
+ if(!co_swap) {
+ co_init();
+ co_swap = (void (fastcall*)(cothread_t, cothread_t))co_swap_function;
+ }
+ if(!co_active_handle) co_active_handle = &co_active_buffer;
+ size += 256; /* allocate additional space for storage */
+ size &= ~15; /* align stack to 16-byte boundary */
+
+ if((handle = (cothread_t)malloc(size))) {
+ long *p = (long*)((char*)handle + size); /* seek to top of stack */
+ *--p = (long)crash; /* crash if entrypoint returns */
+ *--p = (long)entrypoint; /* start of function */
+ *(long*)handle = (long)p; /* stack pointer */
+ }
+
+ return handle;
+}
+
+void co_delete(cothread_t handle) {
+ free(handle);
+}
+
+void co_switch(cothread_t handle) {
+ register cothread_t co_previous_handle = co_active_handle;
+ co_swap(co_active_handle = handle, co_previous_handle);
+}
+
+#ifdef __cplusplus
+}
+#endif