CLI flags

5 files changed, 216 insertions, 65 deletions

diff --git a/README.md b/README.md
index 9a5e138..eb10f22 100644
--- a/README.md
+++ b/README.md
@@ -1 +1 @@
-# btaskt
+# btasktd
diff --git a/src/Makefile b/src/Makefile
index d05ed6d..fa8ddc8 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -20,7 +20,7 @@ clean:
 	$(CC) $(CFLAGS) -c $< -o $@
 
 
-BTASKTD_OBJECTS = btasktd.o
+BTASKTD_OBJECTS = btasktd.o cliflags.o
 BTASKTD_LIBS = -lc
 
 btasktd: $(BTASKTD_OBJECTS)
diff --git a/src/btasktd.c b/src/btasktd.c
index 92f1ce4..34e1fae 100644
--- a/src/btasktd.c
+++ b/src/btasktd.c
@@ -39,83 +39,59 @@
 #include <fcntl.h>
 #include <unistd.h>
 #include <errno.h>
+#include "cliflags.h"
 
-#ifndef BTASKTD_QUEUE_LEN
-#	define QUEUE_LEN 16
-#endif
-
-enum flag_val_res {
-	fvr_not_found = -1,
-	fvr_min = fvr_not_found,
-	fvr_ok = 0,
-	fvr_invalid,
-	fvr_max = fvr_invalid
-};
+#define BTASKTD_HELP_STR \
+	"btasktd - task tracking TCP-server\n" \
+	"flags:\n" \
+	" -p PORT\n" \
+	"    sets the port server should listen to\n" \
+	" -h\n" \
+	"    prints the help message (the server won't start!)\n" \
+	" -V\n" \
+	"    prints version (the server won't start!)\n"
 
-struct str_flag_val {
-	enum flag_val_res code;
-	char *data;
-};
+#define BTASKTD_VERSION_STR \
+	"0.0.0"
 
-struct int_flag_val {
-	enum flag_val_res code;
-	int data;
-};
-
-/* -f the_str */
-static struct str_flag_val
-extract_str_flag(char flagletter, int argc, char **argv)
-{
-	struct str_flag_val res = {0};
-	char flagstr[3] = { '-', ' ', '\0' };
-	int i;
-	flagstr[1] = flagletter;
-	for (i = 1; i < argc; i++)
-		if (0 == strcmp(flagstr, argv[i]))
-			break;
-	if (i >= argc) {
-		res.code = fvr_not_found;
-	} else if (i == argc-1) {
-		res.code = fvr_invalid;
-	} else {
-		res.code = fvr_ok;
-		res.data = argv[i+1];
-	}
-	return res;
-}
+#ifndef BTASKTD_QUEUE_LEN
+#	define BTASKTD_QUEUE_LEN 16
+#endif
 
-/* -f number */
-static struct int_flag_val
-extract_int_flag(char flagletter, int argc, char **argv)
+static void
+fprint_help(FILE *f)
 {
-	struct int_flag_val res;
-	struct str_flag_val strres =
-		extract_str_flag(flagletter, argc, argv);
-	char *endptr;
-	res.code = strres.code;
-	if (res.code != fvr_ok) {
-		return res;
-	}
-	res.data = strtol(strres.data, &endptr, 10);
-	if (*endptr != '\0')
-		res.code = fvr_invalid;
-	return res;
+	fputs(BTASKTD_HELP_STR, f);
 }
 
 int
 main(int argc, char **argv)
 {
-	int server_fd, opt = 1, res, flags, port;
+	int server_fd, opt = 1, res, fflags, port, passed_flags = 1;
 	struct sockaddr_in addr = {0};
-	struct int_flag_val port_res =
-		extract_int_flag('p', argc, argv);
+	struct int_flag_val port_res;
+	struct bool_flag_val show_ver, show_help;
+
+	show_ver = extract_bool_flag('V', argc, argv);
+	if (show_ver.code == fvr_ok && show_ver.data) {
+		printf("btasktd version %s\n", BTASKTD_VERSION_STR);
+		return 0;
+	}
+
+	show_help = extract_bool_flag('h', argc, argv);
+	if (show_help.code == fvr_ok && show_help.data) {
+		fprint_help(stdout);
+		return 0;
+	}
+
+	port_res = extract_int_flag('p', argc, argv);
 	switch (port_res.code) {
 	case fvr_not_found:
 #		ifdef BTASKTD_DEFAULT_PORT
 			port = BTASKTD_DEFAULT_PORT;
 #		else
 			fputs("No port specified!\n", stderr);
-			return 1;
+			passed_flags = 0;
 #		endif
 		break;
 	case fvr_invalid:
@@ -123,6 +99,12 @@ main(int argc, char **argv)
 		return 1;
 	case fvr_ok:
 		port = port_res.data;
+		break;
+	}
+
+	if (!passed_flags) {
+		fprint_help(stderr);
+		return 1;
 	}
 
 	server_fd = socket(AF_INET, SOCK_STREAM, 0);
@@ -139,7 +121,7 @@ main(int argc, char **argv)
 		perror("bind");
 		return 1;
 	}
-	res = listen(server_fd, QUEUE_LEN);
+	res = listen(server_fd, BTASKTD_QUEUE_LEN);
 	if (0 != res) {
 		close(server_fd);
 		perror("listen");
@@ -152,8 +134,8 @@ main(int argc, char **argv)
 		perror("setsockopt");
 		return 1;
 	}
-	flags = fcntl(server_fd, F_GETFL);
-	fcntl(server_fd, F_SETFL, flags|O_NONBLOCK);
+	fflags = fcntl(server_fd, F_GETFL);
+	fcntl(server_fd, F_SETFL, fflags|O_NONBLOCK);
 
 	printf("btaskt server btasktd started on port %d\n", port);
 
diff --git a/src/cliflags.c b/src/cliflags.c
new file mode 100644
index 0000000..f34a889
--- /dev/null
+++ b/src/cliflags.c
@@ -0,0 +1,94 @@
+/*-
+ * Copyright (c) 2026, Mr. Goblin
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided
+ * with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
+ * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "cliflags.h"
+
+/* -f */
+struct bool_flag_val
+extract_bool_flag(char flagletter, int argc, char **argv)
+{
+	struct bool_flag_val res = {0};
+	char flagstr[3] = { '-', ' ', '\0' };
+	int i;
+	flagstr[1] = flagletter;
+	res.code = fvr_not_found;
+	res.data = 0;
+	for (i = 1; i < argc; i++) {
+		if (0 == strcmp(flagstr, argv[i])) {
+			res.code = fvr_ok;
+			res.data = 1;
+			break;
+		}
+	}
+	return res;
+}
+
+/* -f the_str */
+struct str_flag_val
+extract_str_flag(char flagletter, int argc, char **argv)
+{
+	struct str_flag_val res = {0};
+	char flagstr[3] = { '-', ' ', '\0' };
+	int i;
+	flagstr[1] = flagletter;
+	for (i = 1; i < argc; i++)
+		if (0 == strcmp(flagstr, argv[i]))
+			break;
+	if (i >= argc) {
+		res.code = fvr_not_found;
+	} else if (i == argc-1) {
+		res.code = fvr_invalid;
+	} else {
+		res.code = fvr_ok;
+		res.data = argv[i+1];
+	}
+	return res;
+}
+
+/* -f number */
+struct int_flag_val
+extract_int_flag(char flagletter, int argc, char **argv)
+{
+	struct int_flag_val res;
+	struct str_flag_val strres =
+		extract_str_flag(flagletter, argc, argv);
+	char *endptr;
+	res.code = strres.code;
+	if (res.code != fvr_ok) {
+		return res;
+	}
+	res.data = strtol(strres.data, &endptr, 10);
+	if (*endptr != '\0')
+		res.code = fvr_invalid;
+	return res;
+}
diff --git a/src/cliflags.h b/src/cliflags.h
new file mode 100644
index 0000000..21ffebc
--- /dev/null
+++ b/src/cliflags.h
@@ -0,0 +1,75 @@
+/*-
+ * Copyright (c) 2026, Mr. Goblin
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided
+ * with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
+ * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ */
+
+#ifndef BTASKT_CLIFLAGS_H_SENTRY
+#define BTASKT_CLIFLAGS_H_SENTRY
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+enum flag_val_res {
+	fvr_not_found = -1,
+	fvr_min = fvr_not_found,
+	fvr_ok = 0,
+	fvr_invalid,
+	fvr_max = fvr_invalid
+};
+
+struct str_flag_val {
+	enum flag_val_res code;
+	char *data;
+};
+
+struct int_flag_val {
+	enum flag_val_res code;
+	int data;
+};
+
+struct bool_flag_val {
+	enum flag_val_res code;
+	int data;
+};
+
+/* -f */
+struct bool_flag_val
+extract_bool_flag(char flagletter, int argc, char **argv);
+
+/* -f the_str */
+struct str_flag_val
+extract_str_flag(char flagletter, int argc, char **argv);
+
+/* -f number */
+struct int_flag_val
+extract_int_flag(char flagletter, int argc, char **argv);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* BTASKT_CLIFLAGS_H_SENTRY */