Diff: include/lwip/pbuf.h

Revision:

0:51ac1d130fd4

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/lwip/pbuf.h	Fri Jun 22 09:25:39 2012 +0000
@@ -0,0 +1,154 @@
+/*
+ * 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>
+ *
+ */
+
+#ifndef __LWIP_PBUF_H__
+#define __LWIP_PBUF_H__
+
+#include "lwip/opt.h"
+#include "lwip/err.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/** Currently, the pbuf_custom code is only needed for one specific configuration
+ * of IP_FRAG */
+#define LWIP_SUPPORT_CUSTOM_PBUF (IP_FRAG && !IP_FRAG_USES_STATIC_BUF && !LWIP_NETIF_TX_SINGLE_PBUF)
+
+#define PBUF_TRANSPORT_HLEN 20
+#define PBUF_IP_HLEN        20
+
+typedef enum {
+  PBUF_TRANSPORT,
+  PBUF_IP,
+  PBUF_LINK,
+  PBUF_RAW
+} pbuf_layer;
+
+typedef enum {
+  PBUF_RAM, /* pbuf data is stored in RAM */
+  PBUF_ROM, /* pbuf data is stored in ROM */
+  PBUF_REF, /* pbuf comes from the pbuf pool */
+  PBUF_POOL /* pbuf payload refers to RAM */
+} pbuf_type;
+
+
+/** indicates this packet's data should be immediately passed to the application */
+#define PBUF_FLAG_PUSH      0x01U
+/** indicates this is a custom pbuf: pbuf_free and pbuf_header handle such a
+    a pbuf differently */
+#define PBUF_FLAG_IS_CUSTOM 0x02U
+/** indicates this pbuf is UDP multicast to be looped back */
+#define PBUF_FLAG_MCASTLOOP 0x04U
+
+struct pbuf {
+  /** next pbuf in singly linked pbuf chain */
+  struct pbuf *next;
+
+  /** pointer to the actual data in the buffer */
+  void *payload;
+
+  /**
+   * total length of this buffer and all next buffers in chain
+   * belonging to the same packet.
+   *
+   * For non-queue packet chains this is the invariant:
+   * p->tot_len == p->len + (p->next? p->next->tot_len: 0)
+   */
+  u16_t tot_len;
+
+  /** length of this buffer */
+  u16_t len;
+
+  /** pbuf_type as u8_t instead of enum to save space */
+  u8_t /*pbuf_type*/ type;
+
+  /** misc flags */
+  u8_t flags;
+
+  /**
+   * the reference count always equals the number of pointers
+   * that refer to this pbuf. This can be pointers from an application,
+   * the stack itself, or pbuf->next pointers from a chain.
+   */
+  u16_t ref;
+};
+
+#if LWIP_SUPPORT_CUSTOM_PBUF
+/** Prototype for a function to free a custom pbuf */
+typedef void (*pbuf_free_custom_fn)(struct pbuf *p);
+
+/** A custom pbuf: like a pbuf, but following a function pointer to free it. */
+struct pbuf_custom {
+  /** The actual pbuf */
+  struct pbuf pbuf;
+  /** This function is called when pbuf_free deallocates this pbuf(_custom) */
+  pbuf_free_custom_fn custom_free_function;
+};
+#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
+
+/* Initializes the pbuf module. This call is empty for now, but may not be in future. */
+#define pbuf_init()
+
+struct pbuf *pbuf_alloc(pbuf_layer l, u16_t length, pbuf_type type);
+#if LWIP_SUPPORT_CUSTOM_PBUF
+struct pbuf *pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type,
+                                 struct pbuf_custom *p, void *payload_mem,
+                                 u16_t payload_mem_len);
+#endif /* LWIP_SUPPORT_CUSTOM_PBUF */
+void pbuf_realloc(struct pbuf *p, u16_t size); 
+u8_t pbuf_header(struct pbuf *p, s16_t header_size);
+void pbuf_ref(struct pbuf *p);
+u8_t pbuf_free(struct pbuf *p);
+u8_t pbuf_clen(struct pbuf *p);  
+void pbuf_cat(struct pbuf *head, struct pbuf *tail);
+void pbuf_chain(struct pbuf *head, struct pbuf *tail);
+struct pbuf *pbuf_dechain(struct pbuf *p);
+err_t pbuf_copy(struct pbuf *p_to, struct pbuf *p_from);
+u16_t pbuf_copy_partial(struct pbuf *p, void *dataptr, u16_t len, u16_t offset);
+err_t pbuf_take(struct pbuf *buf, const void *dataptr, u16_t len);
+struct pbuf *pbuf_coalesce(struct pbuf *p, pbuf_layer layer);
+#if LWIP_CHECKSUM_ON_COPY
+err_t pbuf_fill_chksum(struct pbuf *p, u16_t start_offset, const void *dataptr,
+                       u16_t len, u16_t *chksum);
+#endif /* LWIP_CHECKSUM_ON_COPY */
+
+u8_t pbuf_get_at(struct pbuf* p, u16_t offset);
+u16_t pbuf_memcmp(struct pbuf* p, u16_t offset, const void* s2, u16_t n);
+u16_t pbuf_memfind(struct pbuf* p, const void* mem, u16_t mem_len, u16_t start_offset);
+u16_t pbuf_strstr(struct pbuf* p, const char* substr);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LWIP_PBUF_H__ */