gpg: Use usual free semantics for packet structure free functions.

* g10/free-packet.c (free_attributes): Turn function into a nop for a
NULL arg.
(free_user_id): Ditto.
(free_compressed): Ditto.
(free_encrypted): Ditto.
(free_plaintext): Ditto.
(release_public_key_parts): Avoid extra check for NULL.
* g10/getkey.c (get_best_pubkey_byname): Ditto.
--

This change avoid surprises because it is common that function named
like free and taking a pointer also have similar semantics.

Signed-off-by: Werner Koch <wk@gnupg.org>

g10/free-packet.c

@@ -114,11 +114,8 @@ release_public_key_parts (PKT_public_key *pk)
       xfree (pk->prefs);
       pk->prefs = NULL;
     }
-  if (pk->user_id)
-    {
   free_user_id (pk->user_id);
   pk->user_id = NULL;
-    }
   if (pk->revkey)
     {
       xfree(pk->revkey);
@@ -293,6 +290,9 @@ free_comment( PKT_comment *rem )
 void
 free_attributes(PKT_user_id *uid)
 {
+  if (!uid)
+    return;
+
   xfree(uid->attribs);
   xfree(uid->attrib_data);
 
@@ -304,6 +304,9 @@ free_attributes(PKT_user_id *uid)
 void
 free_user_id (PKT_user_id *uid)
 {
+  if (!uid)
+    return;
+
   log_assert (uid->ref > 0);
   if (--uid->ref)
     return;
@@ -318,9 +321,14 @@ free_user_id (PKT_user_id *uid)
 void
 free_compressed( PKT_compressed *zd )
 {
-    if( zd->buf ) { /* have to skip some bytes */
+  if (!zd)
-	/* don't have any information about the length, so
+    return;
-	 * we assume this is the last packet */
+
+  if (zd->buf)
+    {
+      /* We need to skip some bytes.  Because don't have any
+       * information about the length, so we assume this is the last
+       * packet */
       while (iobuf_read( zd->buf, NULL, 1<<30 ) != -1)
         ;
     }
@@ -330,13 +338,22 @@ free_compressed( PKT_compressed *zd )
 void
 free_encrypted( PKT_encrypted *ed )
 {
-    if( ed->buf ) { /* have to skip some bytes */
+  if (!ed)
-	if( ed->is_partial ) {
+    return;
+
+  if (ed->buf)
+    {
+      /* We need to skip some bytes. */
+      if (ed->is_partial)
+        {
           while (iobuf_read( ed->buf, NULL, 1<<30 ) != -1)
             ;
 	}
-	else {
+      else
-	   while( ed->len ) { /* skip the packet */
+        {
+          while (ed->len)
+            {
+              /* Skip the packet. */
               int n = iobuf_read( ed->buf, NULL, ed->len );
               if (n == -1)
                 ed->len = 0;
@@ -352,13 +369,20 @@ free_encrypted( PKT_encrypted *ed )
 void
 free_plaintext( PKT_plaintext *pt )
 {
-    if( pt->buf ) { /* have to skip some bytes */
+  if (!pt)
-	if( pt->is_partial ) {
+    return;
+
+  if (pt->buf)
+    { /* We need to skip some bytes.  */
+      if (pt->is_partial)
+        {
           while (iobuf_read( pt->buf, NULL, 1<<30 ) != -1)
             ;
         }
-	else {
+      else
-	   while( pt->len ) { /* skip the packet */
+        {
+          while( pt->len )
+            { /* Skip the packet.  */
               int n = iobuf_read( pt->buf, NULL, pt->len );
               if (n == -1)
                 pt->len = 0;

g10/getkey.c

@@ -1602,7 +1602,6 @@ get_best_pubkey_byname (ctrl_t ctrl, GETKEY_CTX *retctx, PKT_public_key *pk,
             {
               /* New key is better.  */
               release_public_key_parts (&best.key);
-              if (best.uid)
               free_user_id (best.uid);
               best = new;
             }
@@ -1610,20 +1609,17 @@ get_best_pubkey_byname (ctrl_t ctrl, GETKEY_CTX *retctx, PKT_public_key *pk,
             {
               /* Old key is better.  */
               release_public_key_parts (&new.key);
-              if (new.uid)
               free_user_id (new.uid);
             }
           else
             {
               /* A tie.  Keep the old key.  */
               release_public_key_parts (&new.key);
-              if (new.uid)
               free_user_id (new.uid);
             }
         }
       getkey_end (ctx);
       ctx = NULL;
-      if (best.uid)
       free_user_id (best.uid);
 
       if (best.valid)
@@ -3604,7 +3600,6 @@ finish_lookup (kbnode_t keyblock, unsigned int req_usage, int want_exact,
   if (latest_key)
     {
       pk = latest_key->pkt->pkt.public_key;
-      if (pk->user_id)
       free_user_id (pk->user_id);
       pk->user_id = scopy_user_id (foundu);
     }