initial commit of lk (little kernel) project
diff --git a/lib/lwip/src/core/mem.c b/lib/lwip/src/core/mem.c
new file mode 100644
index 0000000..b38d8f1
--- /dev/null
+++ b/lib/lwip/src/core/mem.c
@@ -0,0 +1,310 @@
+/** @file
+ *
+ * Dynamic memory manager
+ *
+ */
+
+/*
+ * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ *
+ * Author: Adam Dunkels <adam@sics.se>
+ *
+ */
+
+#include <string.h>
+
+#include "lwip/arch.h"
+#include "lwip/opt.h"
+#include "lwip/def.h"
+#include "lwip/mem.h"
+
+#include "lwip/sys.h"
+
+#include "lwip/stats.h"
+
+struct mem {
+ mem_size_t next, prev;
+#if MEM_ALIGNMENT == 1
+ u8_t used;
+#elif MEM_ALIGNMENT == 2
+ u16_t used;
+#elif MEM_ALIGNMENT == 4
+ u32_t used;
+#elif MEM_ALIGNMENT == 8
+ u64_t used;
+#else
+#error "unhandled MEM_ALIGNMENT size"
+#endif /* MEM_ALIGNMENT */
+};
+
+static struct mem *ram_end;
+static u8_t ram[MEM_SIZE + sizeof(struct mem) + MEM_ALIGNMENT];
+
+#define MIN_SIZE 12
+#if 0 /* this one does not align correctly for some, resulting in crashes */
+#define SIZEOF_STRUCT_MEM (unsigned int)MEM_ALIGN_SIZE(sizeof(struct mem))
+#else
+#define SIZEOF_STRUCT_MEM (sizeof(struct mem) + \
+ (((sizeof(struct mem) % MEM_ALIGNMENT) == 0)? 0 : \
+ (4 - (sizeof(struct mem) % MEM_ALIGNMENT))))
+#endif
+
+static struct mem *lfree; /* pointer to the lowest free block */
+
+static sys_sem_t mem_sem;
+
+static void
+plug_holes(struct mem *mem)
+{
+ struct mem *nmem;
+ struct mem *pmem;
+
+ LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
+ LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t *)mem < (u8_t *)ram_end);
+ LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
+
+ /* plug hole forward */
+ LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE", mem->next <= MEM_SIZE);
+
+ nmem = (struct mem *)&ram[mem->next];
+ if (mem != nmem && nmem->used == 0 && (u8_t *)nmem != (u8_t *)ram_end) {
+ if (lfree == nmem) {
+ lfree = mem;
+ }
+ mem->next = nmem->next;
+ ((struct mem *)&ram[nmem->next])->prev = (u8_t *)mem - ram;
+ }
+
+ /* plug hole backward */
+ pmem = (struct mem *)&ram[mem->prev];
+ if (pmem != mem && pmem->used == 0) {
+ if (lfree == mem) {
+ lfree = pmem;
+ }
+ pmem->next = mem->next;
+ ((struct mem *)&ram[mem->next])->prev = (u8_t *)pmem - ram;
+ }
+
+}
+void
+mem_init(void)
+{
+ struct mem *mem;
+
+ memset(ram, 0, MEM_SIZE);
+ mem = (struct mem *)ram;
+ mem->next = MEM_SIZE;
+ mem->prev = 0;
+ mem->used = 0;
+ ram_end = (struct mem *)&ram[MEM_SIZE];
+ ram_end->used = 1;
+ ram_end->next = MEM_SIZE;
+ ram_end->prev = MEM_SIZE;
+
+ mem_sem = sys_sem_new(1);
+
+ lfree = (struct mem *)ram;
+
+#if MEM_STATS
+ lwip_stats.mem.avail = MEM_SIZE;
+#endif /* MEM_STATS */
+}
+void
+mem_free(void *rmem)
+{
+ struct mem *mem;
+
+ if (rmem == NULL) {
+ LWIP_DEBUGF(MEM_DEBUG | DBG_TRACE | 2, ("mem_free(p == NULL) was called.\n"));
+ return;
+ }
+
+ sys_sem_wait(mem_sem);
+
+ LWIP_ASSERT("mem_free: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
+ (u8_t *)rmem < (u8_t *)ram_end);
+
+ if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
+ LWIP_DEBUGF(MEM_DEBUG | 3, ("mem_free: illegal memory\n"));
+#if MEM_STATS
+ ++lwip_stats.mem.err;
+#endif /* MEM_STATS */
+ sys_sem_signal(mem_sem);
+ return;
+ }
+ mem = (struct mem *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
+
+ LWIP_ASSERT("mem_free: mem->used", mem->used);
+
+ mem->used = 0;
+
+ if (mem < lfree) {
+ lfree = mem;
+ }
+
+#if MEM_STATS
+ lwip_stats.mem.used -= mem->next - ((u8_t *)mem - ram);
+
+#endif /* MEM_STATS */
+ plug_holes(mem);
+ sys_sem_signal(mem_sem);
+}
+void *
+mem_reallocm(void *rmem, mem_size_t newsize)
+{
+ void *nmem;
+ nmem = mem_malloc(newsize);
+ if (nmem == NULL) {
+ return mem_realloc(rmem, newsize);
+ }
+ memcpy(nmem, rmem, newsize);
+ mem_free(rmem);
+ return nmem;
+}
+
+void *
+mem_realloc(void *rmem, mem_size_t newsize)
+{
+ mem_size_t size;
+ mem_size_t ptr, ptr2;
+ struct mem *mem, *mem2;
+
+ /* Expand the size of the allocated memory region so that we can
+ adjust for alignment. */
+ if ((newsize % MEM_ALIGNMENT) != 0) {
+ newsize += MEM_ALIGNMENT - ((newsize + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT);
+ }
+
+ if (newsize > MEM_SIZE) {
+ return NULL;
+ }
+
+ sys_sem_wait(mem_sem);
+
+ LWIP_ASSERT("mem_realloc: legal memory", (u8_t *)rmem >= (u8_t *)ram &&
+ (u8_t *)rmem < (u8_t *)ram_end);
+
+ if ((u8_t *)rmem < (u8_t *)ram || (u8_t *)rmem >= (u8_t *)ram_end) {
+ LWIP_DEBUGF(MEM_DEBUG | 3, ("mem_realloc: illegal memory\n"));
+ return rmem;
+ }
+ mem = (struct mem *)((u8_t *)rmem - SIZEOF_STRUCT_MEM);
+
+ ptr = (u8_t *)mem - ram;
+
+ size = mem->next - ptr - SIZEOF_STRUCT_MEM;
+#if MEM_STATS
+ lwip_stats.mem.used -= (size - newsize);
+#endif /* MEM_STATS */
+
+ if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE < size) {
+ ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
+ mem2 = (struct mem *)&ram[ptr2];
+ mem2->used = 0;
+ mem2->next = mem->next;
+ mem2->prev = ptr;
+ mem->next = ptr2;
+ if (mem2->next != MEM_SIZE) {
+ ((struct mem *)&ram[mem2->next])->prev = ptr2;
+ }
+
+ plug_holes(mem2);
+ }
+ sys_sem_signal(mem_sem);
+ return rmem;
+}
+void *
+mem_malloc(mem_size_t size)
+{
+ mem_size_t ptr, ptr2;
+ struct mem *mem, *mem2;
+
+ if (size == 0) {
+ return NULL;
+ }
+
+ /* Expand the size of the allocated memory region so that we can
+ adjust for alignment. */
+ if ((size % MEM_ALIGNMENT) != 0) {
+ size += MEM_ALIGNMENT - ((size + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT);
+ }
+
+ if (size > MEM_SIZE) {
+ return NULL;
+ }
+
+ sys_sem_wait(mem_sem);
+
+ for (ptr = (u8_t *)lfree - ram; ptr < MEM_SIZE; ptr = ((struct mem *)&ram[ptr])->next) {
+ mem = (struct mem *)&ram[ptr];
+ if (!mem->used &&
+ mem->next - (ptr + SIZEOF_STRUCT_MEM) >= size + SIZEOF_STRUCT_MEM) {
+ ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
+ mem2 = (struct mem *)&ram[ptr2];
+
+ mem2->prev = ptr;
+ mem2->next = mem->next;
+ mem->next = ptr2;
+ if (mem2->next != MEM_SIZE) {
+ ((struct mem *)&ram[mem2->next])->prev = ptr2;
+ }
+
+ mem2->used = 0;
+ mem->used = 1;
+#if MEM_STATS
+ lwip_stats.mem.used += (size + SIZEOF_STRUCT_MEM);
+ /* if (lwip_stats.mem.max < lwip_stats.mem.used) {
+ lwip_stats.mem.max = lwip_stats.mem.used;
+ } */
+ if (lwip_stats.mem.max < ptr2) {
+ lwip_stats.mem.max = ptr2;
+ }
+#endif /* MEM_STATS */
+
+ if (mem == lfree) {
+ /* Find next free block after mem */
+ while (lfree->used && lfree != ram_end) {
+ lfree = (struct mem *)&ram[lfree->next];
+ }
+ LWIP_ASSERT("mem_malloc: !lfree->used", !lfree->used);
+ }
+ sys_sem_signal(mem_sem);
+ LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
+ (mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
+ LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
+ (unsigned long)((u8_t *)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
+ return (u8_t *)mem + SIZEOF_STRUCT_MEM;
+ }
+ }
+ LWIP_DEBUGF(MEM_DEBUG | 2, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
+#if MEM_STATS
+ ++lwip_stats.mem.err;
+#endif /* MEM_STATS */
+ sys_sem_signal(mem_sem);
+ return NULL;
+}