Add CMake custom commands for generated contents

.clang-format

@@ -0,0 +1,5 @@
+---
+BasedOnStyle: LLVM
+SortIncludes:
+  Enabled:         true
+  IgnoreCase:      false

Makefile

@@ -20,7 +20,7 @@ VERSION?=$(SPECVERSION)
 RELEASE?=cmark-$(VERSION)
 INSTALL_PREFIX?=/usr/local
 CLANG_CHECK?=clang-check
-CLANG_FORMAT=clang-format -style llvm -sort-includes=0 -i
+CLANG_FORMAT=clang-format -i
 AFL_PATH?=/usr/local/bin
 
 .PHONY: all cmake_build leakcheck clean fuzztest test debug ubsan asan mingw archive newbench bench format update-spec afl libFuzzer lint
@@ -141,15 +141,7 @@ $(SRCDIR)/case_fold.inc: $(DATADIR)/CaseFolding.txt
 # We include scanners.c in the repository, so this shouldn't
 # normally need to be generated.
 $(SRCDIR)/scanners.c: $(SRCDIR)/scanners.re
-	@case "$$(re2c -v)" in \
-	    *\ 0.13.*|*\ 0.14|*\ 0.14.1) \
-		echo "re2c >= 0.14.2 is required"; \
-		false; \
-		;; \
-	esac
-	re2c -W -Werror -b -i --no-generation-date \
-		-o $@ $<
-	$(CLANG_FORMAT) $@
+	./tools/make_scanners $< $@
 
 # We include entities.inc in the repository, so normally this
 # doesn't need to be regenerated:

src/CMakeLists.txt

@@ -5,12 +5,49 @@ configure_file(libcmark.pc.in
   ${CMAKE_CURRENT_BINARY_DIR}/libcmark.pc
   @ONLY)
 
+find_program(PYTHON3_EXECUTABLE python3 OPTIONAL)
+
+if(PYTHON3_EXECUTABLE)
+  add_custom_command(
+    OUTPUT case_fold.inc
+    COMMAND ${PYTHON3_EXECUTABLE}
+            ${CMAKE_CURRENT_SOURCE_DIR}/../tools/make_case_fold_inc.py
+            < ${CMAKE_CURRENT_SOURCE_DIR}/../data/CaseFolding.txt
+            > case_fold.inc
+    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/../data/CaseFolding.txt
+    VERBATIM)
+  add_custom_command(
+    OUTPUT entities.inc
+    COMMAND ${PYTHON3_EXECUTABLE}
+            ${CMAKE_CURRENT_SOURCE_DIR}/../tools/make_entities_inc.py
+            > entities.inc
+    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/../tools/make_entities_inc.py
+    VERBATIM)
+endif()
+
+find_program(RE2C_EXECUTABLE re2c OPTIONAL)
+find_program(CLANG_FORMAT_EXECUTABLE clang-format OPTIONAL)
+
+if(RE2C_EXECUTABLE AND CLANG_FORMAT_EXECUTABLE)
+  add_custom_command(
+    OUTPUT scanners.c
+    COMMAND RE2C_EXECUTABLE=${RE2C_EXECUTABLE}
+            CLANG_FORMAT_EXECUTABLE=${CLANG_FORMAT_EXECUTABLE}
+            ${CMAKE_CURRENT_SOURCE_DIR}/../tools/make_scanners
+            ${CMAKE_CURRENT_SOURCE_DIR}/scanners.re
+            scanners.c
+    DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/scanners.re
+    VERBATIM)
+endif()
+
 add_library(cmark
   blocks.c
   buffer.c
+  case_fold.inc
   cmark.c
   cmark_ctype.c
   commonmark.c
+  entities.inc
   houdini_href_e.c
   houdini_html_e.c
   houdini_html_u.c

tools/make_scanners

@@ -0,0 +1,24 @@
+#!/bin/sh
+
+# Creates C scanner code using re2c.
+# Usage: ./tools/make_scanners src/scanners.re src/scanners.c
+# Environment variable: RE2C_EXECUTABLE, CLANG_FORMAT_EXECUTABLE
+
+set -eu
+
+in=${1?no input file}
+out=${2?no output file}
+
+: "${RE2C_EXECUTABLE:=re2c}"
+: "${CLANG_FORMAT_EXECUTABLE:=clang-format}"
+
+case "$("$RE2C_EXECUTABLE" -v)" in
+	*\ 0.13.*|*\ 0.14|*\ 0.14.1)
+		echo "re2c >= 0.14.2 is required"
+		false
+		;;
+esac
+
+"$RE2C_EXECUTABLE" -W -Werror -b -i --no-generation-date \
+	               -o "$out" "$in"
+"$CLANG_FORMAT_EXECUTABLE" -i "$out"