Implement option parsing for fuse. The syntax is:

bcachefs fusemount dev mountpoint
or
bcachefs fusemount dev1:dev2:... mountpoint

diff --git a/cmd_fusemount.c b/cmd_fusemount.c
index 6f9a9be828f47be5528b6f8edf928d61e5ecab61..a9d6305bf6a44733cfeda7c16c0001fe5829d500 100644 (file)
--- a/cmd_fusemount.c
+++ b/cmd_fusemount.c
@@ -556,21 +556,146 @@ static const struct fuse_lowlevel_ops bcachefs_fuse_ops = {
 
 };
 
+/*
+ * Setup and command parsing.
+ */
+
+struct bf_context {
+       char            *devices_str;
+       char            **devices;
+       int             nr_devices;
+};
+
+static void bf_context_free(struct bf_context *ctx)
+{
+       int i;
+
+       free(ctx->devices_str);
+       for (i = 0; i < ctx->nr_devices; ++i)
+               free(ctx->devices[i]);
+       free(ctx->devices);
+}
+
+static struct fuse_opt bf_opts[] = {
+       FUSE_OPT_END
+};
+
+/*
+ * Fuse option parsing helper -- returning 0 means we consumed the argument, 1
+ * means we did not.
+ */
+static int bf_opt_proc(void *data, const char *arg, int key,
+    struct fuse_args *outargs)
+{
+       struct bf_context *ctx = data;
+
+       switch (key) {
+       case FUSE_OPT_KEY_NONOPT:
+               /* Just extract the first non-option string. */
+               if (!ctx->devices_str) {
+                       ctx->devices_str = strdup(arg);
+                       return 0;
+               }
+               return 1;
+       }
+
+       return 1;
+}
+
+/*
+ * dev1:dev2 -> [ dev1, dev2 ]
+ * dev      -> [ dev ]
+ */
+static void tokenize_devices(struct bf_context *ctx)
+{
+       char *devices_str = strdup(ctx->devices_str);
+       char *devices_tmp = devices_str;
+       char **devices = NULL;
+       int nr = 0;
+       char *dev = NULL;
+
+       while ((dev = strsep(&devices_tmp, ":"))) {
+               if (strlen(dev) > 0) {
+                       devices = realloc(devices, (nr + 1) * sizeof *devices);
+                       devices[nr] = strdup(dev);
+                       nr++;
+               }
+       }
+
+       if (!devices) {
+               devices = malloc(sizeof *devices);
+               devices[0] = strdup(ctx->devices_str);
+               nr = 1;
+       }
+
+       ctx->devices = devices;
+       ctx->nr_devices = nr;
+
+       free(devices_str);
+}
+
+static void usage(char *argv[])
+{
+       printf("Usage: %s fusemount [options] <dev>[:dev2:...] <mountpoint>\n",
+              argv[0]);
+       printf("\n");
+}
+
 int cmd_fusemount(int argc, char *argv[])
 {
+       struct fuse_args args = FUSE_ARGS_INIT(argc, argv);
        struct bch_opts bch_opts = bch2_opts_empty();
+       struct bf_context ctx = { 0 };
        struct bch_fs *c = NULL;
+       int ret = 0, i;
 
-       c = bch2_fs_open(argv + optind, argc - optind, bch_opts);
-       if (IS_ERR(c))
-               die("error opening %s: %s", argv[optind],
-                   strerror(-PTR_ERR(c)));
+       /* Parse arguments. */
+       if (fuse_opt_parse(&args, &ctx, bf_opts, bf_opt_proc) < 0)
+               die("fuse_opt_parse err: %m");
 
-       struct fuse_args args = FUSE_ARGS_INIT(argc, argv);
        struct fuse_cmdline_opts fuse_opts;
        if (fuse_parse_cmdline(&args, &fuse_opts) < 0)
                die("fuse_parse_cmdline err: %m");
 
+       if (fuse_opts.show_help) {
+               usage(argv);
+               fuse_cmdline_help();
+               fuse_lowlevel_help();
+               ret = 0;
+               goto out;
+       }
+       if (fuse_opts.show_version) {
+               /* TODO: Show bcachefs version. */
+               printf("FUSE library version %s\n", fuse_pkgversion());
+               fuse_lowlevel_version();
+               ret = 0;
+               goto out;
+       }
+       if (!fuse_opts.mountpoint) {
+               usage(argv);
+               printf("Please supply a mountpoint.\n");
+               ret = 1;
+               goto out;
+       }
+       if (!ctx.devices_str) {
+               usage(argv);
+               printf("Please specify a device or device1:device2:...\n");
+               ret = 1;
+               goto out;
+       }
+       tokenize_devices(&ctx);
+
+       /* Open bch */
+       printf("Opening bcachefs filesystem on:\n");
+       for (i = 0; i < ctx.nr_devices; ++i)
+                printf("\t%s\n", ctx.devices[i]);
+
+       c = bch2_fs_open(ctx.devices, ctx.nr_devices, bch_opts);
+       if (IS_ERR(c))
+               die("error opening %s: %s", ctx.devices_str,
+                   strerror(-PTR_ERR(c)));
+
+       /* Fuse */
        struct fuse_session *se =
                fuse_session_new(&args, &bcachefs_fuse_ops,
                                 sizeof(bcachefs_fuse_ops), c);
@@ -580,15 +705,22 @@ int cmd_fusemount(int argc, char *argv[])
        if (fuse_set_signal_handlers(se) < 0)
                die("fuse_set_signal_handlers err: %m");
 
-       if (fuse_session_mount(se, "/home/kent/mnt"))
+       if (fuse_session_mount(se, fuse_opts.mountpoint))
                die("fuse_mount err: %m");
 
-       int ret = fuse_session_loop(se);
+       fuse_daemonize(fuse_opts.foreground);
 
+       ret = fuse_session_loop(se);
+
+       /* Cleanup */
        fuse_session_unmount(se);
        fuse_remove_signal_handlers(se);
        fuse_session_destroy(se);
+
+out:
+       free(fuse_opts.mountpoint);
        fuse_opt_free_args(&args);
+       bf_context_free(&ctx);
 
        return ret ? 1 : 0;
 }