[RFC] start converting tmpfiles from shell to C

.gitignore

@@ -0,0 +1,9 @@
+# Generated dependency files.
+.deps*
+
+# Compiled objects/libs.
+*.[oa]
+
+# Our project programs.
+/tmpfiles
+/tmpfiles_test

.travis.yml

@@ -6,6 +6,7 @@ compiler:
   - gcc
   - clang
 
+dist: xenial
 os:
   - linux
 

Makefile

@@ -1,12 +1,44 @@
+# Disable implicit rules.  We'll specify everything.
+MAKEFLAGS += -r
+.SUFFIXES:
+
 binprogs = tmpfiles
 bindir = /bin
 binmode = 0755
 install = install
 
+# Clear the default source file search path.  We'll add subdirs below.
+VPATH :=
+
+# This has to come first to define the default target.
 all:
 
+# The build machinery.
+include ./build.mk
+
+# Include generated dependencies.
+-include ./.deps.c
+-include ./.deps.cc
+.deps.c:
+	$(DRIVER_CC) $(CPPFLAGS) -MM $^ >$@
+.deps.cc:
+	$(DRIVER_CXX) $(CPPFLAGS) -MM $^ >$@
+
+# The main program.
+VPATH += src
+include ./src/module.mk
+
+# The tests.
+VPATH += test
+include ./test/module.mk
+check: tmpfiles_test
+	./tmpfiles_test
+
 install:
 	$(install) -d $(DESTDIR)$(bindir)
-	$(install) -m $(binmode) $(binprogs) $(DESTDIR)$(bindir)
+	$(install) -m $(binmode) $(binprogs) $(binprogs).sh $(DESTDIR)$(bindir)
+
+clean:
+	rm -f tmpfiles tmpfiles_test *.o
 
-.PHONY: all install
+.PHONY: all check clean install

build.mk

@@ -0,0 +1,21 @@
+# Compile flags for building the project.
+DEFAULT_FLAGS = -O2 -g
+COMMON_FLAGS = -Wall -fvisibility=hidden -fdiagnostics-color=auto
+CFLAGS ?= $(DEFAULT_FLAGS)
+CFLAGS += $(COMMON_FLAGS) -std=c11
+CXXFLAGS ?= $(DEFAULT_FLAGS)
+CXXFLAGS += $(COMMON_FLAGS) -std=c++14
+CPPFLAGS += -Isrc -D_ISOC11_SOURCE -D_POSIX_C_SOURCE=201401L
+LDFLAGS += -L.
+
+# Generic compiler invocation settings.
+DRIVER_CC = $(CC) $(CFLAGS)
+DRIVER_CXX = $(CXX) $(CXXFLAGS)
+COMPILE_CC = $(DRIVER_CC) $(CPPFLAGS) -c -o $@ $<
+COMPILE_CXX = $(DRIVER_CXX) $(CPPFLAGS) -c -o $@ $<
+LINK_CC = $(DRIVER_CC) $(LDFLAGS) $(LDFLAGS-$@) -o $@ $^ $(LDLIBS) $(LDLIBS-$@)
+LINK_CXX = $(DRIVER_CXX) $(LDFLAGS) $(LDFLAGS-$@) -o $@ $^ $(LDLIBS) $(LDLIBS-$@)
+
+# General pattern rules.
+%.o: %.c ; $(COMPILE_CC)
+%.o: %.cc ; $(COMPILE_CXX)

ci/travis.sh

@@ -40,6 +40,9 @@ m() {
 
 main() {
 	m
+	# The CI doesn't include a usable gtest install, so bootstrap it.
+	m gtest
+	m check
 	m install DESTDIR="${PWD}/destdir"
 }
 main "$@"

src/Makefile

@@ -0,0 +1,3 @@
+# Helper for developers.
+all: ; $(MAKE) -C .. all
+%: ; $(MAKE) -C .. $@

src/cli.c

@@ -0,0 +1,166 @@
+/*
+ * Copyright 2017-2019 Gentoo Foundation
+ * Copyright 2017-2019 The Chromium OS Authors
+ * Released under the 2-clause BSD license.
+ */
+
+#include "tmpfiles.h"
+
+bool verbose = false;
+bool dryrun = false;
+bool do_default = true;
+bool do_boot = false;
+bool do_clean = false;
+bool do_create = false;
+bool do_remove = false;
+
+ordered_set_t cli_files = {};
+ordered_set_t rules_prefix = {};
+ordered_set_t rules_exclude_prefix = {};
+
+/* Order here doesn't matter.  All must have a value of 256+ though. */
+typedef enum {
+	OPT_BOOT = 0x100,
+	OPT_CLEAN,
+	OPT_CREATE,
+	OPT_DRY_RUN,
+	OPT_EXCLUDE_PREFIX,
+	OPT_PREFIX,
+	OPT_REMOVE,
+	OPT_VERBOSE,
+	OPT_VERSION,
+} options;
+
+/*
+ * Order here reflects output order in --help output, so things are loosely
+ * grouped by relationship.  Otherwise, it doesn't matter.
+ */
+#define PARSE_FLAGS "h"
+#define a_argument required_argument
+static struct option const opts[] = {
+	{"boot",           no_argument, NULL, OPT_BOOT},
+	{"create",         no_argument, NULL, OPT_CREATE},
+	{"clean",          no_argument, NULL, OPT_CLEAN},
+	{"remove",         no_argument, NULL, OPT_REMOVE},
+	{"prefix",          a_argument, NULL, OPT_PREFIX},
+	{"exclude-prefix",  a_argument, NULL, OPT_EXCLUDE_PREFIX},
+	{"dry-run",        no_argument, NULL, OPT_DRY_RUN},
+	{"dryrun",         no_argument, NULL, OPT_DRY_RUN},
+	{"verbose",        no_argument, NULL, OPT_VERBOSE},
+	{"help",           no_argument, NULL, 'h'},
+	{"version",        no_argument, NULL, OPT_VERSION},
+	{NULL,             no_argument, NULL, 0x0}
+};
+
+/* Order here must match opts array above. */
+static const char * const opts_help[] = {
+	"Process all boot entries (have a ! in the command)",
+	"Process all f, F, w, d, D, v, p, L, c, b, m and z, Z, t, T, a, A commands",
+	"All paths with an age setting will be cleaned",
+	"Remove directories marked with D or R, and paths marked with r or R",
+	"Only process entries that match the specified paths",
+	"Ignore all entries that match the specified paths",
+	"Don't make any changes; just show what would be done",
+	"Alias to --dry-run",
+	"Run in verbose mode",
+	"Print this help and exit",
+	"Print version and exit",
+	NULL,
+};
+
+attribute_noreturn
+void usage(int status)
+{
+	/* Increase this if a new --longer-option is added. */
+	const int padding = 25;
+	size_t i;
+	int ret;
+	FILE *fp = status == 0 ? stdout : stderr;
+
+	fprintf(fp,
+		"Usage: tmpfiles [options] [files]\n"
+		"\n"
+		"If [files] are specified, only those will be processed.\n"
+		"Basenames are searched, while non-basenames are read directly.\n"
+		"\n"
+		"Options:\n"
+	);
+
+	for (i = 0; opts[i].name; ++i) {
+		if (opts[i].val > '~' || opts[i].val < ' ')
+			fprintf(fp, "      ");
+		else
+			fprintf(fp, "  -%c, ", opts[i].val);
+
+		ret = fprintf(fp, "--%s ", opts[i].name);
+		fprintf(fp, "%-*s", padding - ret,
+			opts[i].has_arg == no_argument ? "" : "<arg>");
+		fprintf(fp, " %s\n", opts_help[i]);
+	}
+
+	exit(status);
+}
+
+#ifndef VERSION
+#define VERSION "git"
+#endif
+attribute_noreturn
+static void version(void)
+{
+	printf("opentmpfiles %s\n", VERSION);
+	exit(0);
+}
+
+void parseargs(int argc, char *argv[])
+{
+	int i;
+
+	ordered_set_init(&cli_files);
+	ordered_set_init(&rules_prefix);
+	ordered_set_init(&rules_exclude_prefix);
+
+	while ((i = getopt_long(argc, argv, PARSE_FLAGS, opts, NULL)) != -1) {
+		switch (i) {
+		case OPT_BOOT:
+			do_default = false;
+			do_boot = true;
+			break;
+		case OPT_CLEAN:
+			do_default = false;
+			do_clean = true;
+			break;
+		case OPT_CREATE:
+			do_default = false;
+			do_create = true;
+			break;
+		case OPT_REMOVE:
+			do_default = false;
+			do_remove = true;
+			break;
+
+		case OPT_EXCLUDE_PREFIX:
+			ordered_set_add(&rules_exclude_prefix, optarg);
+			break;
+		case OPT_PREFIX:
+			ordered_set_add(&rules_prefix, optarg);
+			break;
+
+		case OPT_DRY_RUN:
+			dryrun = true;
+			break;
+		case OPT_VERBOSE:
+			verbose = true;
+			break;
+		case OPT_VERSION:
+			version();
+			break;
+		case 'h':
+			usage(0);
+		default:
+			usage(1);
+		}
+	}
+
+	for (i = optind; i < argc; ++i)
+		ordered_set_add(&cli_files, argv[i]);
+}

src/cli.h

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2017-2019 Gentoo Foundation
+ * Copyright 2017-2019 The Chromium OS Authors
+ * Released under the 2-clause BSD license.
+ */
+
+#ifndef TMPFILES_CLI_H
+#define TMPFILES_CLI_H
+
+#include "set.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* State variables for the program. */
+extern bool verbose;
+extern bool dryrun;
+extern bool do_boot;
+extern bool do_default;
+extern bool do_create;
+extern bool do_clean;
+extern bool do_remove;
+extern ordered_set_t cli_files;
+extern ordered_set_t rules_prefix;
+extern ordered_set_t rules_exclude_prefix;
+
+/* Parse the command line arguments. */
+extern void parseargs(int argc, char *argv[]);
+
+/* Show usage details and exit. */
+attribute_noreturn void usage(int status);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/headers.h

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2017-2019 Gentoo Foundation
+ * Copyright 2017-2019 The Chromium OS Authors
+ * Released under the 2-clause BSD license.
+ */
+
+/*
+ * We keep all the C library headers in this one place.  It might mean we
+ * include more headers than we need to in some modules, but so be it.  The
+ * overall build should still be "fast enough".
+ */
+
+#ifndef TMPFILES_HEADERS_H
+#define TMPFILES_HEADERS_H
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <getopt.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/* Some compiler attributes we find useful. */
+#define attribute_noreturn __attribute__((__noreturn__))
+
+#endif