util: Introduce virReadBufInt16LE and virReadBufInt16BE

In order to read 16 bits of data in the native format and convert add
the 16 bit macros to match existing 32 and 64 bit code.

Signed-off-by: John Ferlan <jferlan@redhat.com>

diff --git a/src/util/virendian.h b/src/util/virendian.h
index eefe48ca6f1f92392948f29b45cc778855ec95ef..97940bd33a52ba280da0b643a21800bc1d5e2f5e 100644 (file)
--- a/src/util/virendian.h
+++ b/src/util/virendian.h
@@ -90,4 +90,28 @@
      ((uint32_t)(uint8_t)((buf)[2]) << 16) |             \
      ((uint32_t)(uint8_t)((buf)[3]) << 24))
 
+/**
+ * virReadBufInt16BE:
+ * @buf: byte to start reading at (can be 'char*' or 'unsigned char*');
+ *       evaluating buf must not have any side effects
+ *
+ * Read 2 bytes at BUF as a big-endian 16-bit number.  Caller is
+ * responsible to avoid reading beyond array bounds.
+ */
+# define virReadBufInt16BE(buf)                          \
+    (((uint16_t)(uint8_t)((buf)[0]) << 8) |              \
+     (uint16_t)(uint8_t)((buf)[1]))
+
+/**
+ * virReadBufInt16LE:
+ * @buf: byte to start reading at (can be 'char*' or 'unsigned char*');
+ *       evaluating buf must not have any side effects
+ *
+ * Read 2 bytes at BUF as a little-endian 16-bit number.  Caller is
+ * responsible to avoid reading beyond array bounds.
+ */
+# define virReadBufInt16LE(buf)                          \
+    ((uint16_t)(uint8_t)((buf)[0]) |                     \
+     ((uint16_t)(uint8_t)((buf)[1]) << 8))
+
 #endif /* __VIR_ENDIAN_H__ */

diff --git a/tests/virendiantest.c b/tests/virendiantest.c
index 407250710e4819200d572f4004d59cc6fc0fc3d1..f858e5cb754341b38756a61e3447810043e53e9c 100644 (file)
--- a/tests/virendiantest.c
+++ b/tests/virendiantest.c
@@ -50,6 +50,15 @@ test1(const void *data ATTRIBUTE_UNUSED)
     if (virReadBufInt32LE(array + 9) != 0x8d8c8b8aU)
         goto cleanup;
 
+    if (virReadBufInt16BE(array) != 0x0102U)
+        goto cleanup;
+    if (virReadBufInt16BE(array + 11) != 0x8c8dU)
+        goto cleanup;
+    if (virReadBufInt16LE(array) != 0x0201U)
+        goto cleanup;
+    if (virReadBufInt16LE(array + 11) != 0x8d8cU)
+        goto cleanup;
+
     ret = 0;
  cleanup:
     return ret;
@@ -81,6 +90,15 @@ test2(const void *data ATTRIBUTE_UNUSED)
     if (virReadBufInt32LE(array + 9) != 0x8d8c8b8aU)
         goto cleanup;
 
+    if (virReadBufInt16BE(array) != 0x0102U)
+        goto cleanup;
+    if (virReadBufInt16BE(array + 11) != 0x8c8dU)
+        goto cleanup;
+    if (virReadBufInt16LE(array) != 0x0201U)
+        goto cleanup;
+    if (virReadBufInt16LE(array + 11) != 0x8d8cU)
+        goto cleanup;
+
     ret = 0;
  cleanup:
     return ret;