Add check-includes.sh: Find redundant includes. Check ifndef:s.

Makefile

@@ -255,7 +255,10 @@ check-python:
 	@# E731 do not assign a lambda expression, use a def
 	@flake8 --ignore=E501,E731 --exclude=contrib/pylightning/lightning/__init__.py ${PYSRC}
 
-check-source: check-makefile check-source-bolt check-whitespace check-markdown check-spelling check-python
+check-includes:
+	@tools/check-includes.sh
+
+check-source: check-makefile check-source-bolt check-whitespace check-markdown check-spelling check-python check-includes
 
 full-check: check check-source
 

tools/check-includes.sh

@@ -0,0 +1,61 @@
+#!/bin/bash
+
+EXIT_CODE=0
+
+# Check include guards
+
+HEADER_ID_PREFIX="LIGHTNING_"
+HEADER_ID_SUFFIX="_H"
+REGEXP_EXCLUDE_FILES_WITH_PREFIX="ccan/"
+for HEADER_FILE in $(git ls-files -- "*.h" | grep -vE "^${REGEXP_EXCLUDE_FILES_WITH_PREFIX}")
+do
+    HEADER_ID_BASE=$(tr / _ <<< "${HEADER_FILE/%.h/}" | tr "[:lower:]" "[:upper:]")
+    HEADER_ID="${HEADER_ID_PREFIX}${HEADER_ID_BASE}${HEADER_ID_SUFFIX}"
+    if [[ $(grep -cE "^#((ifndef|define) ${HEADER_ID}|endif /\* ${HEADER_ID} \*/)$" "${HEADER_FILE}") != 3 ]]; then
+        echo "${HEADER_FILE} seems to be missing the expected include guard:"
+        echo "  #ifndef ${HEADER_ID}"
+        echo "  #define ${HEADER_ID}"
+        echo "  ..."
+        echo "  #endif /* ${HEADER_ID} */"
+        echo
+        EXIT_CODE=1
+    fi
+done
+
+# Check redundant includes
+
+filter_suffix() {
+    git ls-files | grep -v 'ccan/' | grep -E "\.${1}"'$'
+}
+
+for HEADER_FILE in $(filter_suffix h); do
+    DUPLICATE_INCLUDES_IN_HEADER_FILE=$(grep -E "^#include " < "${HEADER_FILE}" | sort | uniq -d)
+    if [[ ${DUPLICATE_INCLUDES_IN_HEADER_FILE} != "" ]]; then
+        echo "Duplicate include(s) in ${HEADER_FILE}:"
+        echo "${DUPLICATE_INCLUDES_IN_HEADER_FILE}"
+        echo
+        EXIT_CODE=1
+    fi
+    C_FILE=${HEADER_FILE/%\.h/.c}
+    if [[ ! -e $C_FILE ]]; then
+        continue
+    fi
+    DUPLICATE_INCLUDES_IN_HEADER_AND_C_FILES=$(grep -hE "^#include " <(sort -u < "${HEADER_FILE}") <(sort -u < "${C_FILE}") | grep -E "^#include " | sort | uniq -d)
+    if [[ ${DUPLICATE_INCLUDES_IN_HEADER_AND_C_FILES} != "" ]]; then
+        echo "Include(s) from ${HEADER_FILE} duplicated in ${C_FILE}:"
+        echo "${DUPLICATE_INCLUDES_IN_HEADER_AND_C_FILES}"
+        echo
+        EXIT_CODE=1
+    fi
+done
+for C_FILE in $(filter_suffix c); do
+    DUPLICATE_INCLUDES_IN_C_FILE=$(grep -E "^#include " < "${C_FILE}" | sort | uniq -d)
+    if [[ ${DUPLICATE_INCLUDES_IN_C_FILE} != "" ]]; then
+        echo "Duplicate include(s) in ${C_FILE}:"
+        echo "${DUPLICATE_INCLUDES_IN_C_FILE}"
+        echo
+        EXIT_CODE=1
+    fi
+done
+
+exit ${EXIT_CODE}