[lwip] configure buffer options and preserve PBUF tailroom

2 files changed, 75 insertions, 8 deletions

diff --git a/components/net/lwip/lwip-2.1.2/src/core/pbuf.c b/components/net/lwip/lwip-2.1.2/src/core/pbuf.c
index a209e0ca8f..40071728e4 100644
--- a/components/net/lwip/lwip-2.1.2/src/core/pbuf.c
+++ b/components/net/lwip/lwip-2.1.2/src/core/pbuf.c
@@ -271,7 +271,10 @@ pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
       break;
     }
     case PBUF_RAM: {
-      u16_t payload_len = (u16_t)(LWIP_MEM_ALIGN_SIZE(offset) + LWIP_MEM_ALIGN_SIZE(length));
+      mem_size_t payload_len = (mem_size_t)(LWIP_MEM_ALIGN_SIZE(offset) + LWIP_MEM_ALIGN_SIZE(length));
+#if PBUF_PAYLOAD_MARGIN_LEN > 0
+      payload_len += LWIP_MEM_ALIGN_SIZE(PBUF_PAYLOAD_MARGIN_LEN);
+#endif
       mem_size_t alloc_len = (mem_size_t)(LWIP_MEM_ALIGN_SIZE(SIZEOF_STRUCT_PBUF) + payload_len);
 
       /* bug #50040: Check for integer overflow when calculating alloc_len */
@@ -440,9 +443,31 @@ pbuf_realloc(struct pbuf *p, u16_t new_len)
       && ((q->flags & PBUF_FLAG_IS_CUSTOM) == 0)
 #endif /* LWIP_SUPPORT_CUSTOM_PBUF */
      ) {
-    /* reallocate and adjust the length of the pbuf that will be split */
-    q = (struct pbuf *)mem_trim(q, (mem_size_t)(((u8_t *)q->payload - (u8_t *)q) + rem_len));
-    LWIP_ASSERT("mem_trim returned q == NULL", q != NULL);
+    size_t trim_len = (size_t)((u8_t *)q->payload - (u8_t *)q);
+#if PBUF_PAYLOAD_MARGIN_LEN > 0
+    size_t margin_len = LWIP_MEM_ALIGN_SIZE((size_t)PBUF_PAYLOAD_MARGIN_LEN);
+#endif
+    /* Keep the original allocation if the aligned trim size would wrap. */
+    int trim_size_ok = (size_t)rem_len <= (size_t)-1 - trim_len;
+#if PBUF_PAYLOAD_MARGIN_LEN > 0
+    trim_size_ok = trim_size_ok &&
+                   margin_len <= (size_t)-1 - trim_len - rem_len;
+#endif
+    if (trim_size_ok) {
+      trim_len += rem_len;
+#if PBUF_PAYLOAD_MARGIN_LEN > 0
+      trim_len += margin_len;
+#endif
+      if (trim_len <= (size_t)((mem_size_t)-1) - (MEM_ALIGNMENT - 1U)) {
+        struct pbuf *trimmed;
+        /* reallocate and adjust the length of the pbuf that will be split */
+        trimmed = (struct pbuf *)mem_trim(q, (mem_size_t)trim_len);
+        LWIP_ASSERT("mem_trim returned q == NULL", trimmed != NULL);
+        if (trimmed != NULL) {
+          q = trimmed;
+        }
+      }
+    }
   }
   /* adjust length fields for new last pbuf */
   q->len = rem_len;
diff --git a/components/net/lwip/port/lwipopts.h b/components/net/lwip/port/lwipopts.h
index 424430c665..7d29d79b6b 100644
--- a/components/net/lwip/port/lwipopts.h
+++ b/components/net/lwip/port/lwipopts.h
@@ -282,14 +282,21 @@
 //#define MEM_LIBC_MALLOC             1
 //#define MEM_USE_POOLS               1
 //#define MEMP_USE_CUSTOM_POOLS       1
-//#define MEM_SIZE                    (1024*64)
+
+#ifdef RT_LWIP_MEM_SIZE
+#define MEM_SIZE                    RT_LWIP_MEM_SIZE
+#endif
 
 #define MEMP_MEM_MALLOC             0
 
 /* MEMP_NUM_PBUF: the number of memp struct pbufs. If the application
    sends a lot of data out of ROM (or other static memory), this
    should be set high. */
+#ifdef RT_LWIP_PBUF_STRUCT_NUM
+#define MEMP_NUM_PBUF               RT_LWIP_PBUF_STRUCT_NUM
+#else
 #define MEMP_NUM_PBUF               32 //16
+#endif
 
 /* the number of struct netconns */
 #ifdef RT_MEMP_NUM_NETCONN
@@ -323,17 +330,44 @@
  * setting in the lwip opts.h
  */
 /* MEMP_NUM_NETBUF: the number of struct netbufs. */
-// #define MEMP_NUM_NETBUF             2
+#ifdef RT_LWIP_MEMP_NUM_NETBUF
+#define MEMP_NUM_NETBUF             RT_LWIP_MEMP_NUM_NETBUF
+#endif
 /* MEMP_NUM_NETCONN: the number of struct netconns. */
 // #define MEMP_NUM_NETCONN            4
 
 /* MEMP_NUM_TCPIP_MSG_*: the number of struct tcpip_msg, which is used
    for sequential API communication and incoming packets. Used in
    src/api/tcpip.c. */
-// #define MEMP_NUM_TCPIP_MSG_API      16
-// #define MEMP_NUM_TCPIP_MSG_INPKT    16
+#ifdef RT_LWIP_TCPIP_MSG_API_NUM
+#define MEMP_NUM_TCPIP_MSG_API      RT_LWIP_TCPIP_MSG_API_NUM
+#endif
+#ifdef RT_LWIP_TCPIP_MSG_INPKT_NUM
+#define MEMP_NUM_TCPIP_MSG_INPKT    RT_LWIP_TCPIP_MSG_INPKT_NUM
+#endif
 
 /* ---------- Pbuf options ---------- */
+
+/* Optional driver-reserved space before and after a PBUF_RAM payload. */
+#ifdef RT_LWIP_PBUF_LINK_ENCAPSULATION_HLEN
+#define PBUF_LINK_ENCAPSULATION_HLEN RT_LWIP_PBUF_LINK_ENCAPSULATION_HLEN
+#endif
+
+#ifdef RT_LWIP_PBUF_PAYLOAD_MARGIN_LEN
+#define PBUF_PAYLOAD_MARGIN_LEN      RT_LWIP_PBUF_PAYLOAD_MARGIN_LEN
+#else
+#define PBUF_PAYLOAD_MARGIN_LEN      0
+#endif
+
+/* Only the bundled lwIP 2.1.2 implements PBUF_RAM tailroom allocation. */
+#if PBUF_PAYLOAD_MARGIN_LEN != 0 && !defined(RT_USING_LWIP212)
+#error "PBUF_PAYLOAD_MARGIN_LEN requires the bundled lwIP 2.1.2 (RT_USING_LWIP212)"
+#endif
+
+#ifdef RT_LWIP_NETIF_TX_SINGLE_PBUF
+#define LWIP_NETIF_TX_SINGLE_PBUF    1
+#endif
+
 /* PBUF_POOL_SIZE: the number of buffers in the pbuf pool. */
 #ifdef RT_LWIP_PBUF_NUM
 #define PBUF_POOL_SIZE               RT_LWIP_PBUF_NUM
@@ -415,7 +449,11 @@
 #define TCPIP_THREAD_STACKSIZE      4096
 #endif
 #define TCPIP_THREAD_NAME           "tcpip"
+#ifdef RT_LWIP_TCP_RECVMBOX_SIZE
+#define DEFAULT_TCP_RECVMBOX_SIZE   RT_LWIP_TCP_RECVMBOX_SIZE
+#else
 #define DEFAULT_TCP_RECVMBOX_SIZE   10
+#endif
 
 /* ---------- ARP options ---------- */
 #define LWIP_ARP                    1
@@ -490,7 +528,11 @@
 
 #define LWIP_UDPLITE                0
 #define UDP_TTL                     255
+#ifdef RT_LWIP_UDP_RECVMBOX_SIZE
+#define DEFAULT_UDP_RECVMBOX_SIZE   RT_LWIP_UDP_RECVMBOX_SIZE
+#else
 #define DEFAULT_UDP_RECVMBOX_SIZE   1
+#endif
 
 /* ---------- RAW options ---------- */
 #ifdef RT_LWIP_RAW