From 08b11a3ad6e293343bfab98a7439a26079db5dea Mon Sep 17 00:00:00 2001
From: arighi <arighi@38d2e660-2303-0410-9eaa-f027e97ec537>
Date: Wed, 3 Nov 2010 10:35:07 +0000
Subject: [PATCH] lwIP: remove dependency on heap module

lwIP now implements its own thread stacks' allocator if CONFIG_KERN_HEAP
is disabled.

git-svn-id: https://src.develer.com/svnoss/bertos/trunk@4497 38d2e660-2303-0410-9eaa-f027e97ec537
---
 bertos/net/lwip.h                   |  2 +-
 bertos/net/lwip/src/arch/sys_arch.c | 21 ++++++++++++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/bertos/net/lwip.h b/bertos/net/lwip.h
index d07e311f..3f592ff0 100644
--- a/bertos/net/lwip.h
+++ b/bertos/net/lwip.h
@@ -35,7 +35,7 @@
  *
  * $WIZ$ module_name = "lwip"
  * $WIZ$ module_configuration = "bertos/cfg/cfg_lwip.h"
- * $WIZ$ module_depends = "kern", "signal", "msg", "event", "eth", "heap"
+ * $WIZ$ module_depends = "kern", "signal", "msg", "event", "eth"
  */
 
 #ifndef NET_LWIP_H
diff --git a/bertos/net/lwip/src/arch/sys_arch.c b/bertos/net/lwip/src/arch/sys_arch.c
index 1d314cc3..a7feddbd 100644
--- a/bertos/net/lwip/src/arch/sys_arch.c
+++ b/bertos/net/lwip/src/arch/sys_arch.c
@@ -336,10 +336,23 @@ static void thread_trampoline(void)
 	thread_node->entry(thread_node->arg);
 }
 
+#if !CONFIG_KERN_HEAP
+/*
+ * NOTE: threads are never destroyed, consequently these stacks are never
+ * deallocated. So, the stack allocator can be implemented as a simple index
+ * that is atomically incremented at each allocation.
+ */
+static cpu_stack_t thread_stack[MAX_THREAD_CNT]
+			[DEFAULT_THREAD_STACKSIZE / sizeof(cpu_stack_t)]
+				ALIGNED(sizeof(cpu_stack_t));
+static int last_stack;
+#endif
+
 sys_thread_t sys_thread_new(char *name, void (* thread)(void *arg),
 				void *arg, int stacksize, int prio)
 {
 	ThreadNode *thread_node;
+	cpu_stack_t *stackbase;
 
 	proc_forbid();
 	thread_node = (ThreadNode *)list_remHead(&free_thread);
@@ -354,8 +367,14 @@ sys_thread_t sys_thread_new(char *name, void (* thread)(void *arg),
 	thread_node->entry = thread;
 	thread_node->arg = arg;
 
+	#if !CONFIG_KERN_HEAP
+		ASSERT(stacksize <= DEFAULT_THREAD_STACKSIZE);
+		PROC_ATOMIC(stackbase = &thread_stack[last_stack++]);
+	#else
+		stackbase = NULL;
+	#endif
 	thread_node->pid = proc_new_with_name(name, thread_trampoline,
-				(void *)thread_node, stacksize, NULL);
+				(void *)thread_node, stacksize, stackbase);
 	if (thread_node->pid == NULL)
 		return NULL;
 
-- 
2.25.1