build: improve char escaping of syntax lists

Escape `.` only when generating the syntax files rather than directly in
the syntax lists, so that the latter contain the command names as is.

This also makes the escaping apply to the arg1 syntax list as well.

Note: Double escaping (`\\\\.`) is used in `regex_fromlf` because its
output is used in another sed replacement (where it needs to be `\\.`).

Relates to #5627.

Makefile

@@ -106,13 +106,13 @@ syntax: $(SYNTAX_FILES)
 contrib/syntax/lists/profile_commands_arg0.list: src/firejail/profile.c Makefile
 	@printf 'Generating %s from %s\n' $@ $<
 	@sed -En 's/.*strn?cmp\(ptr, "([^ "]*[^ ])".*/\1/p' $< | \
-	grep -Ev '^(include|rlimit)$$' | sed 's/\./\\./' | LC_ALL=C sort -u >$@
+	grep -Ev '^(include|rlimit)$$' | LC_ALL=C sort -u >$@
 
 # TODO: private-lib is special-cased in the code and doesn't match the regex
 contrib/syntax/lists/profile_commands_arg1.list: src/firejail/profile.c Makefile
 	@printf 'Generating %s from %s\n' $@ $<
-	@{ sed -En 's/.*strn?cmp\(ptr, "([^"]+) ".*/\1/p' $<; echo private-lib; } | \
-	LC_ALL=C sort -u >$@
+	@{ sed -En 's/.*strn?cmp\(ptr, "([^"]+) ".*/\1/p' $<; \
+	   echo private-lib; } | LC_ALL=C sort -u >$@
 
 contrib/syntax/lists/profile_conditionals.list: src/firejail/profile.c Makefile
 	@printf 'Generating %s from %s\n' $@ $<
@@ -139,17 +139,17 @@ contrib/syntax/lists/system_errnos.list: src/lib/errno.c Makefile
 	@printf 'Generating %s from %s\n' $@ $<
 	@sed -En 's/.*"(E[^"]+).*/\1/p' $< | LC_ALL=C sort -u >$@
 
-pipe_fromlf = { tr '\n' '|' | sed 's/|$$//'; }
-space_fromlf = { tr '\n' ' ' | sed 's/ $$//'; }
+regex_fromlf = { tr '\n' '|' | sed -e 's/|$$//' -e 's/\./\\\\./g'; }
+space_fromlf = { tr '\n' ' ' | sed -e 's/ $$//'; }
 edit_syntax_file = sed \
 	-e "s/@make_input@/$$(basename $@).  Generated from $$(basename $<) by make./" \
-	-e "s/@FJ_PROFILE_COMMANDS_ARG0@/$$($(pipe_fromlf) <contrib/syntax/lists/profile_commands_arg0.list)/" \
-	-e "s/@FJ_PROFILE_COMMANDS_ARG1@/$$($(pipe_fromlf) <contrib/syntax/lists/profile_commands_arg1.list)/" \
-	-e "s/@FJ_PROFILE_CONDITIONALS@/$$($(pipe_fromlf) <contrib/syntax/lists/profile_conditionals.list)/" \
-	-e "s/@FJ_PROFILE_MACROS@/$$($(pipe_fromlf) <contrib/syntax/lists/profile_macros.list)/" \
+	-e "s/@FJ_PROFILE_COMMANDS_ARG0@/$$($(regex_fromlf) <contrib/syntax/lists/profile_commands_arg0.list)/" \
+	-e "s/@FJ_PROFILE_COMMANDS_ARG1@/$$($(regex_fromlf) <contrib/syntax/lists/profile_commands_arg1.list)/" \
+	-e "s/@FJ_PROFILE_CONDITIONALS@/$$($(regex_fromlf) <contrib/syntax/lists/profile_conditionals.list)/" \
+	-e "s/@FJ_PROFILE_MACROS@/$$($(regex_fromlf) <contrib/syntax/lists/profile_macros.list)/" \
 	-e "s/@FJ_SYSCALLS@/$$($(space_fromlf) <contrib/syntax/lists/syscalls.list)/" \
-	-e "s/@FJ_SYSCALL_GROUPS@/$$($(pipe_fromlf) <contrib/syntax/lists/syscall_groups.list)/" \
-	-e "s/@FJ_SYSTEM_ERRNOS@/$$($(pipe_fromlf) <contrib/syntax/lists/system_errnos.list)/"
+	-e "s/@FJ_SYSCALL_GROUPS@/$$($(regex_fromlf) <contrib/syntax/lists/syscall_groups.list)/" \
+	-e "s/@FJ_SYSTEM_ERRNOS@/$$($(regex_fromlf) <contrib/syntax/lists/system_errnos.list)/"
 
 contrib/syntax/files/example: contrib/syntax/files/example.in $(SYNTAX_LISTS) Makefile
 	@printf 'Generating %s from %s\n' $@ $<

contrib/syntax/lists/profile_commands_arg0.list

@@ -41,7 +41,7 @@ private-tmp
 quiet
 restrict-namespaces
 seccomp
-seccomp\.block-secondary
+seccomp.block-secondary
 tab
 tracelog
 writable-etc