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Fix wvstreams so that it builds with uClibc, which does not have the
getcontext() and setcontext() functions.
Signed-off-by: Simon Dawson <spdawson@gmail.com>
diff -Nurp a/include/wvtask.h b/include/wvtask.h
--- a/include/wvtask.h 2008-07-14 20:11:35.000000000 +0100
+++ b/include/wvtask.h 2012-07-28 12:29:53.559981240 +0100
@@ -28,6 +28,13 @@
#define WVTASK_MAGIC 0x123678
+#undef HAVE_GETCONTEXT
+#ifdef HAVE_GETCONTEXT
+typedef ucontext_t TaskContext;
+#else
+typedef jmp_buf TaskContext;
+#endif
+
class WvTaskMan;
/** Represents a single thread of control. */
@@ -54,8 +61,8 @@ class WvTask
bool running, recycled;
WvTaskMan &man;
- ucontext_t mystate; // used for resuming the task
- ucontext_t func_call, func_return;
+ TaskContext mystate; // used for resuming the task
+ TaskContext func_call, func_return;
TaskFunc *func;
void *userdata;
@@ -94,13 +101,13 @@ class WvTaskMan
static void call_func(WvTask *task);
static char *stacktop;
- static ucontext_t stackmaster_task;
+ static TaskContext stackmaster_task;
static WvTask *stack_target;
- static ucontext_t get_stack_return;
+ static TaskContext get_stack_return;
static WvTask *current_task;
- static ucontext_t toplevel;
+ static TaskContext toplevel;
WvTaskMan();
virtual ~WvTaskMan();
diff -Nurp a/utils/wvtask.cc b/utils/wvtask.cc
--- a/utils/wvtask.cc 2009-05-13 22:42:52.000000000 +0100
+++ b/utils/wvtask.cc 2012-07-28 12:32:23.855974538 +0100
@@ -60,12 +60,14 @@ int WvTask::taskcount, WvTask::numtasks,
WvTaskMan *WvTaskMan::singleton;
int WvTaskMan::links, WvTaskMan::magic_number;
WvTaskList WvTaskMan::all_tasks, WvTaskMan::free_tasks;
-ucontext_t WvTaskMan::stackmaster_task, WvTaskMan::get_stack_return,
+TaskContext WvTaskMan::stackmaster_task, WvTaskMan::get_stack_return,
WvTaskMan::toplevel;
WvTask *WvTaskMan::current_task, *WvTaskMan::stack_target;
char *WvTaskMan::stacktop;
+#ifdef HAVE_GETCONTEXT
static int context_return;
+#endif
static bool use_shared_stack()
@@ -198,9 +200,13 @@ WvTaskMan::WvTaskMan()
stacktop = (char *)alloca(0);
+#ifdef HAVE_GETCONTEXT
context_return = 0;
assert(getcontext(&get_stack_return) == 0);
if (context_return == 0)
+#else
+ if (setjmp(get_stack_return) == 0)
+#endif
{
// initial setup - start the stackmaster() task (never returns!)
stackmaster();
@@ -257,22 +263,30 @@ int WvTaskMan::run(WvTask &task, int val
WvTask *old_task = current_task;
current_task = &task;
- ucontext_t *state;
+ TaskContext *state;
if (!old_task)
state = &toplevel; // top-level call (not in an actual task yet)
else
state = &old_task->mystate;
+#ifdef HAVE_GETCONTEXT
context_return = 0;
assert(getcontext(state) == 0);
int newval = context_return;
+#else
+ int newval = setjmp(*state);
+#endif
if (newval == 0)
{
// saved the state, now run the task.
+#ifdef HAVE_GETCONTEXT
context_return = val;
setcontext(&task.mystate);
return -1;
+#else
+ longjmp(task.mystate, val);
+#endif
}
else
{
@@ -317,16 +331,24 @@ int WvTaskMan::yield(int val)
(long)current_task->stacksize);
}
#endif
-
+
+#ifdef HAVE_GETCONTEXT
context_return = 0;
assert(getcontext(¤t_task->mystate) == 0);
int newval = context_return;
+#else
+ int newval = setjmp(current_task->mystate);
+#endif
if (newval == 0)
{
// saved the task state; now yield to the toplevel.
+#ifdef HAVE_GETCONTEXT
context_return = val;
setcontext(&toplevel);
return -1;
+#else
+ longjmp(toplevel, val);
+#endif
}
else
{
@@ -340,9 +362,13 @@ int WvTaskMan::yield(int val)
void WvTaskMan::get_stack(WvTask &task, size_t size)
{
+#ifdef HAVE_GETCONTEXT
context_return = 0;
assert(getcontext(&get_stack_return) == 0);
if (context_return == 0)
+#else
+ if (setjmp(get_stack_return) == 0)
+#endif
{
assert(magic_number == -WVTASK_MAGIC);
assert(task.magic_number == WVTASK_MAGIC);
@@ -358,6 +384,7 @@ void WvTaskMan::get_stack(WvTask &task,
static char *next_stack_addr = NULL;
#endif
+#ifndef HAVE_GETCONTEXT
task.stack = mmap(next_stack_addr, task.stacksize,
PROT_READ | PROT_WRITE,
#ifndef MACOS
@@ -366,12 +393,17 @@ void WvTaskMan::get_stack(WvTask &task,
MAP_PRIVATE,
#endif
-1, 0);
+#endif // !HAVE_GETCONTEXT
}
// initial setup
stack_target = &task;
+#ifdef HAVE_GETCONTEXT
context_return = size/1024 + (size%1024 > 0);
setcontext(&stackmaster_task);
+#else
+ longjmp(stackmaster_task, size/1024 + (size%1024 > 0));
+#endif
}
else
{
@@ -408,9 +440,13 @@ void WvTaskMan::_stackmaster()
{
assert(magic_number == -WVTASK_MAGIC);
+#ifdef HAVE_GETCONTEXT
context_return = 0;
assert(getcontext(&stackmaster_task) == 0);
val = context_return;
+#else
+ val = setjmp(stackmaster_task);
+#endif
if (val == 0)
{
assert(magic_number == -WVTASK_MAGIC);
@@ -418,8 +454,12 @@ void WvTaskMan::_stackmaster()
// just did setjmp; save stackmaster's current state (with
// all current stack allocations) and go back to get_stack
// (or the constructor, if that's what called us)
+#ifdef HAVE_GETCONTEXT
context_return = 1;
setcontext(&get_stack_return);
+#else
+ longjmp(get_stack_return, 1);
+#endif
}
else
{
@@ -462,7 +502,9 @@ void WvTaskMan::call_func(WvTask *task)
task->func(task->userdata);
Dprintf("WvTaskMan: returning from task #%d (%s)\n",
task->tid, (const char *)task->name);
+#ifdef HAVE_GETCONTEXT
context_return = 1;
+#endif
}
@@ -473,9 +515,13 @@ void WvTaskMan::do_task()
assert(task->magic_number == WVTASK_MAGIC);
// back here from longjmp; someone wants stack space.
+#ifdef HAVE_GETCONTEXT
context_return = 0;
assert(getcontext(&task->mystate) == 0);
if (context_return == 0)
+#else
+ if (setjmp(task->mystate) == 0)
+#endif
{
// done the setjmp; that means the target task now has
// a working jmp_buf all set up. Leave space on the stack
@@ -510,6 +556,7 @@ void WvTaskMan::do_task()
}
else
{
+#ifdef HAVE_GETCONTEXT
assert(getcontext(&task->func_call) == 0);
task->func_call.uc_stack.ss_size = task->stacksize;
task->func_call.uc_stack.ss_sp = task->stack;
@@ -519,11 +566,19 @@ void WvTaskMan::do_task()
task->tid, (const char *)task->name);
makecontext(&task->func_call,
(void (*)(void))call_func, 1, task);
+#else
+ assert(setjmp(task->func_call) == 0);
+#endif
+#ifdef HAVE_GETCONTEXT
context_return = 0;
assert(getcontext(&task->func_return) == 0);
if (context_return == 0)
setcontext(&task->func_call);
+#else
+ if (setjmp(task->func_return) == 0)
+ longjmp(task->func_call, 0);
+#endif
}
// the task's function terminated.
@@ -544,8 +599,12 @@ const void *WvTaskMan::current_top_of_st
if (use_shared_stack() || current_task == NULL)
return __libc_stack_end;
else
+#ifdef HAVE_GETCONTEXT
return (const char *)current_task->stack + current_task->stacksize;
#else
+ return 0;
+#endif
+#else
return 0;
#endif
}
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