[LTP] [RFC PATCH 1/4] Add scripts to remove TEST in library

[Richard Palethorpe]

---
 .../coccinelle/libltp-test-macro-vars.cocci   |  54 +++++++
 scripts/coccinelle/libltp-test-macro.cocci    | 137 ++++++++++++++++++
 2 files changed, 191 insertions(+)
 create mode 100644 scripts/coccinelle/libltp-test-macro-vars.cocci
 create mode 100644 scripts/coccinelle/libltp-test-macro.cocci

diff --git a/scripts/coccinelle/libltp-test-macro-vars.cocci b/scripts/coccinelle/libltp-test-macro-vars.cocci
new file mode 100644
index 000000000..679ce80fe
--- /dev/null
+++ b/scripts/coccinelle/libltp-test-macro-vars.cocci
@@ -0,0 +1,54 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright (c) 2021 SUSE LLC  <rpalethorpe@suse.com>
+
+// The TEST macro should not be used in the library because it sets
+// TST_RET and TST_ERR which are global variables. The test author
+// only expects these to be changed if *they* call TEST directly.
+
+// Set with -D fix
+virtual fix
+// Set with -D report
+virtual report
+
+// Find all positions where TEST's variables are used
+@ find_use exists @
+identifier tst_var =~ "TST_(ERR|RET)";
+position p;
+expression E;
+@@
+
+(
+ tst_var@p
+|
+ TTERRNO@p | E
+)
+
+@initialize:python depends on report@
+@@
+
+import json
+
+errors = []
+
+@script:python depends on report@
+p << find_use.p;
+@@
+
+msg = {
+    'msg': "TEST macro variable use in library",
+    'file': p[0].file,
+    'line': p[0].line,
+    'col': p[0].column,
+}
+
+errors.append(msg)
+
+@finalize:python depends on report@
+@@
+
+msgs = {
+     'check_script': 'coccinelle/libltp-test-macro-vars.cocci',
+     'errors': errors,
+}
+
+print(json.dumps(msgs, indent=2))
diff --git a/scripts/coccinelle/libltp-test-macro.cocci b/scripts/coccinelle/libltp-test-macro.cocci
new file mode 100644
index 000000000..960b5d325
--- /dev/null
+++ b/scripts/coccinelle/libltp-test-macro.cocci
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright (c) 2021 SUSE LLC  <rpalethorpe@suse.com>
+
+// The TEST macro should not be used in the library because it sets
+// TST_RET and TST_ERR which are global variables. The test author
+// only expects these to be changed if *they* call TEST directly.
+
+// Set with -D fix
+virtual fix
+// Set with -D report
+virtual report
+
+// Find all positions where TEST is _used_.
+@ find_use exists @
+position p;
+@@
+
+ TEST@p(...);
+
+// Print the position of the TEST usage
+@initialize:python depends on report@
+@@
+
+import json
+
+errors = []
+
+@script:python depends on report@
+p << find_use.p;
+@@
+
+msg = {
+    'msg': "TEST macro use in library",
+    'file': p[0].file,
+    'line': p[0].line,
+    'col': p[0].column,
+}
+
+errors.append(msg)
+
+@finalize:python depends on report@
+@@
+
+msgs = {
+     'check_script': 'coccinelle/libltp-test-macro.cocci',
+     'errors': errors,
+}
+
+print(json.dumps(msgs, indent=2))
+
+// Below are rules which will create a patch to replace TEST usage
+// It assumes we can use the ret var without conflicts
+
+// Fix all references to the variables TEST modifies when they occur in a
+// function where TEST was used.
+@ depends on fix && find_use @
+@@
+
+(
+- TST_RET
++ ret
+|
+- TST_ERR
++ errno
+|
+- TTERRNO
++ TERRNO
+)
+
+// Replace TEST in all functions where it occurs only at the start. It
+// is slightly complicated by adding a newline if a statement appears
+// on the line after TEST(). It is not clear to me what the rules are
+// for matching whitespace as it has no semantic meaning, but this
+// appears to work.
+@ depends on fix @
+identifier fn;
+expression tested_expr;
+statement st;
+@@
+
+  fn (...)
+  {
+- 	TEST(tested_expr);
++	const long ret = tested_expr;
+(
++
+	st
+|
+
+)
+	... when != TEST(...)
+  }
+
+// Replace TEST in all functions where it occurs at the start
+// Functions where it *only* occurs at the start were handled above
+@ depends on fix @
+identifier fn;
+expression tested_expr;
+statement st;
+@@
+
+  fn (...)
+  {
+- 	TEST(tested_expr);
++	long ret = tested_expr;
+(
++
+	st
+|
+
+)
+	...
+  }
+
+// Add ret var at the start of a function where TEST occurs and there
+// is not already a ret declaration
+@ depends on fix exists @
+identifier fn;
+@@
+
+  fn (...)
+  {
++	long ret;
+	... when != long ret;
+
+	TEST(...)
+	...
+  }
+
+// Replace any remaining occurances of TEST
+@ depends on fix @
+expression tested_expr;
+@@
+
+- 	TEST(tested_expr);
++	ret = tested_expr;
+
-- 
2.31.1