Changeset 3e6bca8 in mainline for uspace/lib/inet/src/eth_addr.c

Timestamp:

2021-08-08T17:30:29Z (3 years ago)

Author:

Jiri Svoboda <jiri@…>

Branches:

master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

a7f7b9c3

Parents:

b4edc96

Message:

Represent Ethernet address as a number instead of an array

Carefully document the design since this breaks the principle of least
surprise. Also add unit tests.

File:

• uspace/lib/inet/src/eth_addr.c (modified) (3 diffs)

uspace/lib/inet/src/eth_addr.c

@@ -37 +37 @@
 #include <inet/eth_addr.h>
 #include <mem.h>
+#include <stdio.h>
 
-const eth_addr_t eth_addr_broadcast = {
-        0xff, 0xff, 0xff, 0xff, 0xff, 0xff
-};
+const eth_addr_t eth_addr_broadcast =
+    ETH_ADDR_INITIALIZER(0xff, 0xff, 0xff, 0xff, 0xff, 0xff);
 
 void eth_addr_encode(eth_addr_t *addr, void *buf)
 {
         uint8_t *bp = (uint8_t *)buf;
+        uint64_t a;
+        int i;
 
-        memcpy(bp, &addr->b[0], ETH_ADDR_SIZE);
+        a = addr->a;
+
+        for (i = 0; i < ETH_ADDR_SIZE; i++)
+                bp[i] = (a >> (40 - 8 * i)) & 0xff;
 }
 
@@ -52 +57 @@
 {
         const uint8_t *bp = (uint8_t *)buf;
+        uint64_t a;
+        int i;
 
-        memcpy(&addr->b[0], bp, ETH_ADDR_SIZE);
+        a = 0;
+        for (i = 0; i < ETH_ADDR_SIZE; i++)
+                a |= (uint64_t)bp[i] << (40 - 8 * i);
+
+        addr->a = a;
 }
 
@@ -62 +73 @@
 int eth_addr_compare(const eth_addr_t *a, const eth_addr_t *b)
 {
-        return memcmp(a->b, b->b, ETH_ADDR_SIZE) == 0;
+        if (a->a < b->a)
+                return -1;
+        else if (a->a == b->a)
+                return 0;
+        else
+                return 1;
+}
+
+void eth_addr_format(eth_addr_t *addr, eth_addr_str_t *saddr)
+{
+        int i;
+
+        snprintf(saddr->str, 3, "%02x",
+            (unsigned)((addr->a >> 40) & 0xff));
+        for (i = 1; i < ETH_ADDR_SIZE; i++) {
+                snprintf(saddr->str + 2 + 3 * (i - 1), 4, ":%02x",
+                    (unsigned)((addr->a >> (40 - i * 8)) & 0xff));
+        }
 }