scripts: add coccinelle

scripts/coccinelle/andconst.cocci

@@ -0,0 +1,18 @@
+// Two comparisons of the same expression to different constants,
+// connected by a conjunction
+// Confidence: Moderate
+// Copyright: (C) Diego Liziero
+// URL: https://coccinelle.gitlabpages.inria.fr/website/rules/andconst.html
+// Options:
+
+@@ identifier i; constant C1,C2; @@
+(
+- i == C1 && i == C2
++ i == C1 || i == C2
+)
+
+@@ identifier i; constant C1,C2; @@
+(
+- i != C1 || i != C2
++ i != C1 && i != C2
+)

scripts/coccinelle/bad_return_type.cocci

@@ -0,0 +1,34 @@
+@@
+type T, B != T;
+identifier func, i;
+expression E;
+@@
+
+T func (...) {
+...
+(
+T i;
+|
+T i = E;
+|
+static B i;
+|
+static B i = E;
+|
+-B i;
++T i;
+|
+-B i = E;
++T i = E;
+)
+<+...
+(
+return i;
+|
+return (T) i;
+)
+...+>
+}
+
+
+

scripts/coccinelle/badzero.cocci

@@ -0,0 +1,51 @@
+// A pointer should not be compared to zero
+//
+// Confidence: High
+// Copyright: (C) Gilles Muller, Julia Lawall, EMN, INRIA, DIKU.  GPLv2.
+// URL: https://coccinelle.gitlabpages.inria.fr/website/rules/badzero.html
+// Options:
+
+@ disable is_zero,isnt_zero @
+expression *E;
+expression E1,f;
+@@
+
+E = f(...)
+<...
+(
+- E == 0
++ !E    
+|
+- E != 0
++ E
+|
+- 0 == E
++ !E
+|
+- 0 != E
++ E
+)
+...>
+?E = E1
+
+@ disable is_zero,isnt_zero @
+expression *E;
+@@
+
+(
+  E == 
+- 0
++ NULL  
+|
+  E !=
+- 0
++ NULL  
+|
+- 0
++ NULL
+  == E
+|
+- 0
++ NULL
+  != E
+)

scripts/coccinelle/coccicheck.sh

@@ -0,0 +1,39 @@
+#!/bin/sh
+set -eu
+
+read -p "Type the path to the testing folder [src/bin]: " path
+if [ -z $path ]; then
+   path='src/bin'
+else
+   path=$path
+fi
+
+COCCI_FILES="
+andconst.cocci
+badzero.cocci
+continue.cocci
+free_stack.cocci
+mutex.cocci
+notand.cocci
+notnull.cocci
+null_ref.cocci
+unused.cocci
+use_after_iter.cocci
+macros.cocci
+"
+
+HAS_ERROR=0
+for f in $COCCI_FILES; do
+   OPTIONS=""
+   if [ "$f" = "macros.cocci" ]; then
+      OPTIONS="--defined DIV_ROUND_UP --defined ROUND_UP --defined MIN --defined MAX"
+   fi
+   CMD="spatch --timeout 200 --very-quiet --cocci-file scripts/coccinelle/$f --include-headers --dir $path $OPTIONS"
+   OUT=$($CMD)
+   echo "$CMD"
+   if [ -n "$OUT" ]; then
+      echo "$OUT"
+      HAS_ERROR=1
+   fi
+done
+exit $HAS_ERROR

scripts/coccinelle/continue.cocci

@@ -0,0 +1,17 @@
+// Continue at the end of a for loop has no purpose
+//
+// Confidence: Moderate
+// Copyright: (C) Gilles Muller, Julia Lawall, EMN, INRIA, DIKU.  GPLv2.
+// URL: https://coccinelle.gitlabpages.inria.fr/website/rules/continue.html
+// Options:
+
+@@
+@@
+
+for (...;...;...) {
+   ...
+   if (...) {
+     ...
+-   continue;
+   }
+}

scripts/coccinelle/free_stack.cocci

@@ -0,0 +1,15 @@
+// For fun, but gcc actually detects those by itself
+@@
+type T;
+identifier K;
+expression E;
+@@
+(
+(
+T K;
+|
+T K = E;
+)
+...
+- free(&K);
+)

scripts/coccinelle/macros.cocci

@@ -0,0 +1,38 @@
+// DIV_ROUND_UP
+@@
+expression n, d;
+@@
+(
+- (((n + d) - 1) / d)
++ DIV_ROUND_UP(n, d)
+|
+- ((n + (d - 1)) / d)
++ DIV_ROUND_UP(n, d)
+)
+
+// ROUND_UP
+@@
+expression n, d;
+@@
+(
+- ((((n + d) - 1) / d) * d)
++ ROUND_UP(n, d)
+|
+- (((n + (d - 1)) / d) * d)
++ ROUND_UP(n, d)
+|
+- (DIV_ROUND_UP(n,d) * d)
++ ROUND_UP(n, d)
+)
+
+// MIN / MAX
+@@
+expression x, y;
+@@
+(
+- (((x) > (y)) ? (y) : (x))
++ MIN(x, y)
+|
+- (((x) > (y)) ? (x) : (y))
++ MAX(x, y)
+)

scripts/coccinelle/mutex.cocci

@@ -0,0 +1,38 @@
+// A mutex_lock is not matched by a mutex_unlock before an error return/goto.
+@@
+expression l;
+identifier LOCK =~ "^.*_lock$";
+identifier UN =~ "^.*_unlock$";
+@@
+
+LOCK(l);
+... when != UN(l)
+    when any
+    when strict
+(
+{ ... when != UN(l)
++   todo_add_unlock(l);
+    return ...;
+}
+|
+UN(l);
+)
+
+
+// unlock from not locked code
+//@@
+//expression E;
+//identifier LOCK =~ "^.*_lock$";
+//identifier UN =~ "^.*_unlock$";
+//@@
+//... when != LOCK(E)
+//(
+//if (...) {
+//+add_LOCK(E);
+//... when != LOCK(E)
+// UN(E);
+// return ...;
+//}
+//|
+//UN(E)
+//)

scripts/coccinelle/notand.cocci

@@ -0,0 +1,14 @@
+// !x&y combines boolean negation with bitwise and
+//
+// Confidence: High
+// Copyright: (C) Gilles Muller, Julia Lawall, EMN, INRIA, DIKU.  GPLv2.
+// URL: https://coccinelle.gitlabpages.inria.fr/website/rules/notand.html
+// Options:
+
+@@ expression E; constant C; @@
+(
+  !E & !C
+|
+- !E & C
++ !(E & C)
+)

scripts/coccinelle/notnull.cocci

@@ -0,0 +1,104 @@
+// this detects NULL tests that can only be reached when the value is known 
+// not to be NULL
+//
+// Confidence: High
+// Copyright: (C) Gilles Muller, Julia Lawall, EMN, INRIA, DIKU.  GPLv2.
+// URL: https://coccinelle.gitlabpages.inria.fr/website/rules/notnull.html
+// Options:
+
+@r exists@
+local idexpression x;
+expression E;
+position p1,p2;
+@@
+
+if (x@p1 == NULL || ...) { ... when forall
+   return ...; }
+... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\)
+    when != &x
+(
+x@p2 == NULL
+|
+x@p2 != NULL
+)
+
+// another path to the test that is not through p1?
+
+@s exists@
+local idexpression r.x;
+position r.p1,r.p2;
+@@
+
+... when != x@p1
+(
+x@p2 == NULL
+|
+x@p2 != NULL
+)
+
+// another path to the test from p1?
+
+@t exists@
+local idexpression x;
+position r.p1,r.p2;
+@@
+
+if (x@p1 == NULL || ...) { ... x@p2 ... when any
+   return ...; }
+
+// another path to the test containing an assignment?
+
+@u exists@
+local idexpression x;
+expression E;
+position r.p1,r.p2;
+@@
+
+if (x@p1 == NULL || ...) { ... when forall
+   return ...; }
+ ...
+ \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
+ ...  when != x@p1
+      when any
+(
+x@p2 == NULL
+|
+x@p2 != NULL
+)
+
+@fix depends on !s && !t && !u@
+position r.p2;
+expression x,E;
+statement S1,S2;
+@@
+
+(
+- if ((x@p2 != NULL) || ...)
+  S1
+|
+- if ((x@p2 != NULL) || ...)
+  S1
+- else S2
+|
+- (x@p2 != NULL) && E
++ E
+|
+- (x@p2 == NULL) || E
++ E
+|
+- if ((x@p2 == NULL) && ...) S1
+|
+- if ((x@p2 == NULL) && ...) S1 else
+  S2
+|
+- BUG_ON(x@p2 == NULL);
+)
+
+@script:python depends on !s && !t && !u && !fix@
+p1 << r.p1;
+p2 << r.p2;
+@@
+
+cocci.print_main("",p1)
+cocci.print_secs("retest",p2)
+