Initial commit

This initial commit has enough to make a new file system and print out
it's structures.

Signed-off-by: Zach Brown <zab@versity.com>

utils/src/cmd.c

@@ -0,0 +1,82 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include <string.h>
+#include <assert.h>
+
+#include "cmd.h"
+#include "util.h"
+
+static struct command {
+	char *name;
+	char *opts;
+	char *summary;
+	int (*func)(int argc, char **argv);
+} cmds[100], *next_cmd = cmds;
+
+#define cmd_for_each(com) for (com = cmds; com->func; com++)
+
+void cmd_register(char *name, char *opts, char *summary,
+		  int (*func)(int argc, char **argv))
+{
+	struct command *com = next_cmd++;
+
+	assert((com - cmds) < array_size(cmds));
+
+	com->name = name;
+	com->opts = opts;
+	com->summary = summary;
+	com->func = func;
+}
+
+static struct command *find_command(char *name)
+{
+	struct command *com;
+
+	cmd_for_each(com) {
+		if (!strcmp(name, com->name))
+			return com;
+	}
+
+	return NULL;
+}
+
+static void usage(void)
+{
+	struct command *com;
+
+	fprintf(stderr, "usage: scoutfs <command> [<args>]\n"
+	       "Commands:\n");
+
+	cmd_for_each(com) {
+		fprintf(stderr, "  %8s %12s - %s\n",
+			com->name, com->opts, com->summary);
+	}
+}
+
+int cmd_execute(int argc, char **argv)
+{
+	struct command *com = NULL;
+	int ret;
+
+	if (argc > 1) {
+		com = find_command(argv[1]);
+		if (!com)
+			fprintf(stderr, "scoutfs: unrecognized command: '%s'\n",
+				argv[1]);
+	}
+	if (!com) {
+		usage();
+		return 1;
+	}
+
+	ret = com->func(argc - 2, argv + 2);
+	if (ret < 0) {
+		fprintf(stderr, "scoutfs: %s failed: %s (%d)\n",
+			com->name, strerror(-ret), -ret);
+		return 1;
+	}
+
+	return 0;
+}