xref: /haiku/src/add-ons/kernel/file_systems/userlandfs/server/fuse/helper.c (revision 4a55cc230cf7566cadcbb23b1928eefff8aea9a2)
1 /*
2   FUSE: Filesystem in Userspace
3   Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
4 
5   This program can be distributed under the terms of the GNU LGPLv2.
6   See the file COPYING.LIB.
7 */
8 
9 #include "config.h"
10 #include "fuse_api.h"
11 #include "fuse_misc.h"
12 #include "fuse_opt.h"
13 #include "fuse_lowlevel.h"
14 #include "fuse_common_compat.h"
15 
16 #include <stdio.h>
17 #include <stdlib.h>
18 #include <stddef.h>
19 #include <unistd.h>
20 #include <string.h>
21 #include <limits.h>
22 #include <errno.h>
23 #include <sys/param.h>
24 
25 enum  {
26 	KEY_HELP,
27 	KEY_HELP_NOHEADER,
28 	KEY_VERSION,
29 };
30 
31 struct helper_opts {
32 	int singlethread;
33 	int foreground;
34 	int nodefault_subtype;
35 	char *mountpoint;
36 };
37 
38 #define FUSE_HELPER_OPT(t, p) { t, offsetof(struct helper_opts, p), 1 }
39 
40 static const struct fuse_opt fuse_helper_opts[] = {
41 	FUSE_HELPER_OPT("-d",		foreground),
42 	FUSE_HELPER_OPT("debug",	foreground),
43 	FUSE_HELPER_OPT("-f",		foreground),
44 	FUSE_HELPER_OPT("-s",		singlethread),
45 	FUSE_HELPER_OPT("fsname=",	nodefault_subtype),
46 	FUSE_HELPER_OPT("subtype=",	nodefault_subtype),
47 
48 	FUSE_OPT_KEY("-h",		KEY_HELP),
49 	FUSE_OPT_KEY("--help",		KEY_HELP),
50 	FUSE_OPT_KEY("-ho",		KEY_HELP_NOHEADER),
51 	FUSE_OPT_KEY("-V",		KEY_VERSION),
52 	FUSE_OPT_KEY("--version",	KEY_VERSION),
53 	FUSE_OPT_KEY("-d",		FUSE_OPT_KEY_KEEP),
54 	FUSE_OPT_KEY("debug",		FUSE_OPT_KEY_KEEP),
55 	FUSE_OPT_KEY("fsname=",		FUSE_OPT_KEY_KEEP),
56 	FUSE_OPT_KEY("subtype=",	FUSE_OPT_KEY_KEEP),
57 	FUSE_OPT_END
58 };
59 
60 static void usage(const char *progname)
61 {
62 	fprintf(stderr,
63 		"usage: %s mountpoint [options]\n\n", progname);
64 	fprintf(stderr,
65 		"general options:\n"
66 		"    -o opt,[opt...]        mount options\n"
67 		"    -h   --help            print help\n"
68 		"    -V   --version         print version\n"
69 		"\n");
70 }
71 
72 static void helper_help(void)
73 {
74 	fprintf(stderr,
75 		"FUSE options:\n"
76 		"    -d   -o debug          enable debug output (implies -f)\n"
77 		"    -f                     foreground operation\n"
78 		"    -s                     disable multi-threaded operation\n"
79 		"\n"
80 		);
81 }
82 
83 static void helper_version(void)
84 {
85 	fprintf(stderr, "FUSE library version: %s\n", PACKAGE_VERSION);
86 }
87 
88 static int fuse_helper_opt_proc(void *data, const char *arg, int key,
89 				struct fuse_args *outargs)
90 {
91 	struct helper_opts *hopts = data;
92 
93 	switch (key) {
94 	case KEY_HELP:
95 		usage(outargs->argv[0]);
96 		/* fall through */
97 
98 	case KEY_HELP_NOHEADER:
99 		helper_help();
100 		return fuse_opt_add_arg(outargs, "-h");
101 
102 	case KEY_VERSION:
103 		helper_version();
104 		return 1;
105 
106 	case FUSE_OPT_KEY_NONOPT:
107 		if (!hopts->mountpoint) {
108 			char mountpoint[PATH_MAX];
109 			if (realpath(arg, mountpoint) == NULL) {
110 				fprintf(stderr,
111 					"fuse: bad mount point `%s': %s\n",
112 					arg, strerror(errno));
113 				return -1;
114 			}
115 			return fuse_opt_add_opt(&hopts->mountpoint, mountpoint);
116 		} else {
117 			fprintf(stderr, "fuse: invalid argument `%s'\n", arg);
118 			return -1;
119 		}
120 
121 	default:
122 		return 1;
123 	}
124 }
125 
126 static int add_default_subtype(const char *progname, struct fuse_args *args)
127 {
128 	int res;
129 	char *subtype_opt;
130 	const char *basename = strrchr(progname, '/');
131 	if (basename == NULL)
132 		basename = progname;
133 	else if (basename[1] != '\0')
134 		basename++;
135 
136 	subtype_opt = (char *) malloc(strlen(basename) + 64);
137 	if (subtype_opt == NULL) {
138 		fprintf(stderr, "fuse: memory allocation failed\n");
139 		return -1;
140 	}
141 	sprintf(subtype_opt, "-osubtype=%s", basename);
142 	res = fuse_opt_add_arg(args, subtype_opt);
143 	free(subtype_opt);
144 	return res;
145 }
146 
147 int fuse_parse_cmdline(struct fuse_args *args, char **mountpoint,
148 		       int *multithreaded, int *foreground)
149 {
150 	int res;
151 	struct helper_opts hopts;
152 
153 	memset(&hopts, 0, sizeof(hopts));
154 	res = fuse_opt_parse(args, &hopts, fuse_helper_opts,
155 			     fuse_helper_opt_proc);
156 	if (res == -1)
157 		return -1;
158 
159 	if (!hopts.nodefault_subtype) {
160 		res = add_default_subtype(args->argv[0], args);
161 		if (res == -1)
162 			goto err;
163 	}
164 	if (mountpoint)
165 		*mountpoint = hopts.mountpoint;
166 	else
167 		free(hopts.mountpoint);
168 
169 	if (multithreaded)
170 		*multithreaded = !hopts.singlethread;
171 	if (foreground)
172 		*foreground = hopts.foreground;
173 	return 0;
174 
175 err:
176 	free(hopts.mountpoint);
177 	return -1;
178 }
179 
180 int fuse_daemonize(int foreground)
181 {
182 	// On Haiku, always run "foreground", the userlandfs_server already takes care of running
183 	// as a server if needed.
184 	return 0;
185 }
186 
187