[PATCH] Re-examine and simplify code where "return" is followed by "else"

Try to make the code flow more linear.  Handle easy cases early.  This
avoids unnecessary identation and a complex tree structure of the code.

In at76_iw_handler_get_power(), an at76_dbg() call was supposed to cover
the "disabled" case but would not actually be called.  Fix it.

Signed-off-by: Pavel Roskin <proski@gnu.org>

1 files changed, 96 insertions, 103 deletions

diff --git a/at76_usb.c b/at76_usb.c
index 3e84c7b..d6572f7 100644
--- a/at76_usb.c
+++ b/at76_usb.c
@@ -396,10 +396,10 @@ static int at76_usbdfu_download(struct usb_device *udev, u8 *dfu_buffer,
 
       exit:
 	kfree(dmabuf);
-	if (ret < 0)
-		return ret;
-	else
-		return 0;
+	if (ret >= 0)
+		ret = 0;
+
+	return ret;
 }
 
 /* Report that the scan results are ready */
@@ -3247,17 +3247,14 @@ static int at76_iw_handler_get_power(struct net_device *netdev,
 {
 	struct at76_priv *priv = netdev_priv(netdev);
 
-	if ((power->disabled = (priv->pm_mode == AT76_PM_OFF)))
-		return 0;
-	else {
-		power->flags = IW_POWER_PERIOD;
+	power->disabled = (priv->pm_mode == AT76_PM_OFF);
+	if (!power->disabled) {
+		power->flags = IW_POWER_PERIOD | IW_POWER_ALL_R;
 		power->value = priv->pm_period;
 	}
-	power->flags |= IW_POWER_ALL_R;
 
-	at76_dbg(DBG_IOCTL,
-		 "%s: SIOCGIWPOWER - disabled %s flags x%x value x%x",
-		 netdev->name, (power->disabled) ? "true" : "false",
+	at76_dbg(DBG_IOCTL, "%s: SIOCGIWPOWER - %s flags x%x value x%x",
+		 netdev->name, power->disabled ? "disabled" : "enabled",
 		 power->flags, power->value);
 
 	return 0;
@@ -5501,113 +5498,109 @@ static struct sk_buff *at76_check_for_rx_frags(struct at76_priv *priv)
 		if (bptr->seqnr == seqnr) {
 			int left;
 			/* the fragment has the current sequence number */
-			if (((bptr->fragnr + 1) & 0xf) == fragnr) {
-				bptr->last_rx = jiffies;
-				/* the next following fragment number ->
-				   add the data at the end */
-				/* is & 0xf necessary above ??? */
-
-				/* for test only ??? */
-				left = skb_tailroom(bptr->skb);
-				if (left < data_len) {
-					printk(KERN_INFO
-					       "%s: only %d byte free (need %d)\n",
-					       priv->netdev->name, left,
-					       data_len);
-				} else
-					memcpy(skb_put(bptr->skb, data_len),
-					       data, data_len);
-				bptr->fragnr = fragnr;
-				if (!(frame_ctl & IEEE80211_FCTL_MOREFRAGS)) {
-					/* this was the last fragment - send it */
-					skb = bptr->skb;
-					bptr->skb = NULL;	/* free the entry */
-					at76_dbg(DBG_RX_FRAGS,
-						 "%s: last frag of seq %d",
-						 priv->netdev->name, seqnr);
-					return skb;
-				} else
-					return NULL;
-			} else {
+			if (((bptr->fragnr + 1) & 0xf) != fragnr) {
 				/* wrong fragment number -> ignore it */
+				/* is & 0xf necessary above ??? */
 				at76_dbg(DBG_RX_FRAGS,
 					 "%s: frag nr does not match: %d+1 != %d",
 					 priv->netdev->name, bptr->fragnr,
 					 fragnr);
 				return NULL;
 			}
-		} else {
-			/* got another sequence number */
-			if (fragnr == 0) {
-				/* it's the start of a new chain - replace the
-				   old one by this */
-				/* bptr->sender has the correct value already */
-				at76_dbg(DBG_RX_FRAGS,
-					 "%s: start of new seq %d, "
-					 "removing old seq %d",
-					 priv->netdev->name, seqnr,
-					 bptr->seqnr);
-				bptr->seqnr = seqnr;
-				bptr->fragnr = 0;
-				bptr->last_rx = jiffies;
-				/* swap bptr->skb and priv->rx_skb */
-				skb = bptr->skb;
-				bptr->skb = priv->rx_skb;
-				priv->rx_skb = skb;
-			} else {
-				/* it from the middle of a new chain ->
-				   delete the old entry and skip the new one */
-				at76_dbg(DBG_RX_FRAGS,
-					 "%s: middle of new seq %d (%d) "
-					 "removing old seq %d",
-					 priv->netdev->name, seqnr, fragnr,
-					 bptr->seqnr);
-				dev_kfree_skb(bptr->skb);
-				bptr->skb = NULL;
-			}
-			return NULL;
-		}
-	} else {
-		/* if we didn't find a chain for the sender address optr
-		   points either to the first free or the oldest entry */
+			bptr->last_rx = jiffies;
+			/* the next following fragment number ->
+			   add the data at the end */
 
-		if (fragnr != 0) {
-			/* this is not the begin of a fragment chain ... */
-			at76_dbg(DBG_RX_FRAGS,
-				 "%s: no chain for non-first fragment (%d)",
-				 priv->netdev->name, fragnr);
-			return NULL;
+			/* for test only ??? */
+			left = skb_tailroom(bptr->skb);
+			if (left < data_len) {
+				printk(KERN_INFO
+				       "%s: only %d byte free (need %d)\n",
+				       priv->netdev->name, left, data_len);
+			} else
+				memcpy(skb_put(bptr->skb, data_len), data,
+				       data_len);
+			bptr->fragnr = fragnr;
+			if (frame_ctl & IEEE80211_FCTL_MOREFRAGS)
+				return NULL;
+
+			/* this was the last fragment - send it */
+			skb = bptr->skb;
+			bptr->skb = NULL;	/* free the entry */
+			at76_dbg(DBG_RX_FRAGS, "%s: last frag of seq %d",
+				 priv->netdev->name, seqnr);
+			return skb;
 		}
-		at76_assert(optr != NULL);
-		if (optr == NULL)
-			return NULL;
-
-		if (optr->skb != NULL) {
-			/* swap the skb's */
-			skb = optr->skb;
-			optr->skb = priv->rx_skb;
-			priv->rx_skb = skb;
 
+		/* got another sequence number */
+		if (fragnr == 0) {
+			/* it's the start of a new chain - replace the
+			   old one by this */
+			/* bptr->sender has the correct value already */
 			at76_dbg(DBG_RX_FRAGS,
-				 "%s: free old contents: sender %s seq/frag %d/%d",
-				 priv->netdev->name, mac2str(optr->sender),
-				 optr->seqnr, optr->fragnr);
-
+				 "%s: start of new seq %d, removing old seq %d",
+				 priv->netdev->name, seqnr, bptr->seqnr);
+			bptr->seqnr = seqnr;
+			bptr->fragnr = 0;
+			bptr->last_rx = jiffies;
+			/* swap bptr->skb and priv->rx_skb */
+			skb = bptr->skb;
+			bptr->skb = priv->rx_skb;
+			priv->rx_skb = skb;
 		} else {
-			/* take the skb from priv->rx_skb */
-			optr->skb = priv->rx_skb;
-			priv->rx_skb = NULL;	/* let at76_submit_rx_urb() allocate a new skb */
-
-			at76_dbg(DBG_RX_FRAGS, "%s: use a free entry",
-				 priv->netdev->name);
+			/* it from the middle of a new chain ->
+			   delete the old entry and skip the new one */
+			at76_dbg(DBG_RX_FRAGS,
+				 "%s: middle of new seq %d (%d) "
+				 "removing old seq %d",
+				 priv->netdev->name, seqnr, fragnr,
+				 bptr->seqnr);
+			dev_kfree_skb(bptr->skb);
+			bptr->skb = NULL;
 		}
-		memcpy(optr->sender, i802_11_hdr->addr2, ETH_ALEN);
-		optr->seqnr = seqnr;
-		optr->fragnr = 0;
-		optr->last_rx = jiffies;
+		return NULL;
+	}
 
+	/* if we didn't find a chain for the sender address, optr
+	   points either to the first free or the oldest entry */
+
+	if (fragnr != 0) {
+		/* this is not the begin of a fragment chain ... */
+		at76_dbg(DBG_RX_FRAGS,
+			 "%s: no chain for non-first fragment (%d)",
+			 priv->netdev->name, fragnr);
 		return NULL;
 	}
+	at76_assert(optr != NULL);
+	if (optr == NULL)
+		return NULL;
+
+	if (optr->skb != NULL) {
+		/* swap the skb's */
+		skb = optr->skb;
+		optr->skb = priv->rx_skb;
+		priv->rx_skb = skb;
+
+		at76_dbg(DBG_RX_FRAGS,
+			 "%s: free old contents: sender %s seq/frag %d/%d",
+			 priv->netdev->name, mac2str(optr->sender),
+			 optr->seqnr, optr->fragnr);
+
+	} else {
+		/* take the skb from priv->rx_skb */
+		optr->skb = priv->rx_skb;
+		/* let at76_submit_rx_urb() allocate a new skb */
+		priv->rx_skb = NULL;
+
+		at76_dbg(DBG_RX_FRAGS, "%s: use a free entry",
+			 priv->netdev->name);
+	}
+	memcpy(optr->sender, i802_11_hdr->addr2, ETH_ALEN);
+	optr->seqnr = seqnr;
+	optr->fragnr = 0;
+	optr->last_rx = jiffies;
+
+	return NULL;
 }
 
 /* Rx interrupt: we expect the complete data buffer in priv->rx_skb */