Add Al's comments in from https://lkml.org/lkml/2013/3/20/345
Signed-off-by: Joe Perches <j...@perches.com>
---
diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle
index e00b8f0..c4ba183 100644
--- a/Documentation/CodingStyle
+++ b/Documentation/CodingStyle
@@ -836,6 +836,141 @@ next instruction in the assembly output:
: /* outputs */ : /* inputs */ : /* clobbers */);
+ Chapter 20:
+
+Tips to avoid overly tab indented code.
+
+Tip 1:
+ if (foo) {
+ A /* two lines */
+ } else {
+ B /* huge pile of shite */
+ }
+ return result;
+
+is equivalent to
+
+ if (foo) {
+ A
+ return result;
+ }
+ B
+ return result;
+
+Tip 2:
+ while (1) {
+ A /* a couple of lines */
+ if (foo) {
+ break;
+ } else {
+ B /* huge pile of shite */
+ }
+ }
+
+is equivalent to
+
+ while (1) {
+ A
+ if (foo)
+ break;
+ B
+ }
+
+Tip 3:
+ while (1) {
+ A /* moderate pile of shite, assigning foo */
+ if (foo) {
+ B /* huge pile of shite */
+ }
+ }
+
+is equivalent to
+
+ while (1) {
+ A
+ if (!foo)
+ continue;
+ B
+ }
+
+Tip 4:
+
+functions are there for purpose. When you have two identical piles of
+garbage (avert your eyes, or risk taking another look at your dinner)
+such as
+ int unit, sign, min;
+ unit =
+ (data.value >> 10) &
+ 0x7;
+ sign =
+ (data.value >> 13) &
+ 0x1;
+ min =
+ (data.value >> 14) &
+ 0xfffff;
+
+ switch (unit) {
+ case 0:{
+ min =
+ min
+ *
+ 1000000;
+ }
+ break;
+ case 1:{
+ min =
+ min
+ *
+ 1000;
+ }
+ break;
+ case 2:{
+ min =
+ min
+ * 1;
+ }
+ break;
+ }
+ if (sign)
+ min = -min;
+
+you just might consider turning that pile of excrements into a helper
+function. Incidentally, min = min * 1 is somewhat, er, pointless...
+
+Tip 5:
+ for (i = 0; i <= 4; i++) {
+ {
+ switch (i) {
+ case 0: c = non_NULL_1; ... break;
+ case 1: c = non_NULL_2; ... break;
+ case 2: c = non_NULL_3; ... break;
+ case 3: c = non_NULL_4; ... break;
+ case 4: c = non_NULL_5; ... break;
+ default: c = NULL; break;
+ }
+ if (c) {
+ pile_of_shite
+ }
+ }
+might, perhaps, be taking defensive programming a bit too far...
+
+Tip 6:
+The Vogon whose brain has produced that code up had been brought up on Pascal,
+Ada or something worse, and had been badly traumatized by semantics of switch
+and break.
+ switch (foo) {
+ case 0: {
+ bar = baz;
+ } break;
+ case 1: {
+ .....
+ }
+ is not quite conventional for C.
+
+Tip 7:
+Code flow is down, not across...
+
+
Appendix I: References
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