[PATCH v3] buffer: Fix some issues with -DVERIFY_ALIGNMENT

From: Frank Lichtenheld <[email protected]>

- Fix some uninitalised fields due to BUF_INIT_TRACKING
  (found by cppcheck and the original reason for this
   change).
- Fix "unused functions" if only BUF_INIT_TRACKING is
  defined.
- Fix conversion error

Change-Id: I3ecb76d9022dcd7dae92eb5e9d62e5f018744883
Signed-off-by: Frank Lichtenheld <[email protected]>
Acked-by: Gert Doering <[email protected]>
Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/1666
---

This change was reviewed on Gerrit and approved by at least one
developer. I request to merge it to master.

Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/1666
This mail reflects revision 3 of this Change.

Acked-by according to Gerrit (reflected above):
Gert Doering <[email protected]>

        
diff --git a/src/openvpn/buffer.c b/src/openvpn/buffer.c
index 71f3769..1e19137 100644
--- a/src/openvpn/buffer.c
+++ b/src/openvpn/buffer.c
@@ -64,14 +64,13 @@
 #endif
 {
     struct buffer buf;
+    CLEAR(buf);
 
     if (!buf_size_valid(size))
     {
         buf_size_error(size);
     }
     buf.capacity = (int)size;
-    buf.offset = 0;
-    buf.len = 0;
 #ifdef DMALLOC
     buf.data = openvpn_dmalloc(file, line, size);
 #else
@@ -90,13 +89,13 @@
 #endif
 {
     struct buffer buf;
+    CLEAR(buf);
+
     if (!buf_size_valid(size))
     {
         buf_size_error(size);
     }
     buf.capacity = (int)size;
-    buf.offset = 0;
-    buf.len = 0;
 #ifdef DMALLOC
     buf.data = (uint8_t *)gc_malloc_debug(size, false, gc, file, line);
 #else
@@ -120,6 +119,10 @@
     ret.capacity = buf->capacity;
     ret.offset = buf->offset;
     ret.len = buf->len;
+#ifdef BUF_INIT_TRACKING
+    ret.debug_file = buf->debug_file;
+    ret.debug_line = buf->debug_line;
+#endif
 #ifdef DMALLOC
     ret.data = (uint8_t *)openvpn_dmalloc(file, line, buf->capacity);
 #else
@@ -140,6 +143,7 @@
     return buf_init_dowork(buf, offset);
 }
 
+#ifdef VERIFY_ALIGNMENT
 static inline int
 buf_debug_line(const struct buffer *buf)
 {
@@ -151,6 +155,7 @@
 {
     return buf->debug_file;
 }
+#endif
 
 #else /* ifdef BUF_INIT_TRACKING */
 
@@ -1152,7 +1157,7 @@
     if (buf && buf->len)
     {
         msglvl_t msglevel = D_ALIGN_DEBUG;
-        const unsigned int u = (unsigned int)BPTR(buf);
+        const uintptr_t u = (uintptr_t)BPTR(buf);
 
         if (u & (PAYLOAD_ALIGN - 1))
         {