examples/fuse_nfs.c

   1 /*
   2    Copyright (C) by Ronnie Sahlberg <ronniesahlberg@gmail.com> 2013
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17 /* A FUSE filesystem based on libnfs. */
  18
  19 #define FUSE_USE_VERSION 26
  20 #define _FILE_OFFSET_BITS 64
  21
  22 #include <fuse.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <errno.h>
  27 #include <fcntl.h>
  28 #include <getopt.h>
  29
  30 #include <nfsc/libnfs.h>
  31
  32 #define discard_const(ptr) ((void *)((intptr_t)(ptr)))
  33
  34 struct nfs_context *nfs = NULL;
  35
  36 static int fuse_nfs_getattr(const char *path, struct stat *stbuf)
  37 {
  38         int ret = 0;
  39
  40         memset(stbuf, 0, sizeof(struct stat));
  41         ret = nfs_stat(nfs, path, stbuf);
  42
  43         return ret;
  44 }
  45
  46 static int fuse_nfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
  47                          off_t offset, struct fuse_file_info *fi)
  48 {
  49         struct nfsdir *nfsdir;
  50         struct nfsdirent *nfsdirent;
  51
  52         int ret = 0;
  53
  54         ret = nfs_opendir(nfs, path, &nfsdir);
  55         if (ret < 0) {
  56                 return ret;
  57         }
  58         while ((nfsdirent = nfs_readdir(nfs, nfsdir)) != NULL) {
  59                 filler(buf, nfsdirent->name, NULL, 0);
  60         }
  61
  62         return ret;
  63 }
  64
  65 static int fuse_nfs_open(const char *path, struct fuse_file_info *fi)
  66 {
  67         int ret = 0;
  68         struct nfsfh *nfsfh;
  69
  70         fi->fh = 0;
  71         ret = nfs_open(nfs, path, fi->flags, &nfsfh);
  72         if (ret < 0) {
  73                 return ret;
  74         }
  75
  76         fi->fh = (uint64_t)nfsfh;
  77
  78         return ret;
  79 }
  80
  81 static int fuse_nfs_release(const char *path, struct fuse_file_info *fi)
  82 {
  83         struct nfsfh *nfsfh = (struct nfsfh *)fi->fh;
  84
  85         nfs_close(nfs, nfsfh);
  86         return 0;
  87 }
  88
  89 static int fuse_nfs_read(const char *path, char *buf, size_t size,
  90        off_t offset, struct fuse_file_info *fi)
  91 {
  92         int ret = 0;
  93         struct nfsfh *nfsfh = (struct nfsfh *)fi->fh;
  94
  95         ret = nfs_pread(nfs, nfsfh, offset, size, buf);
  96
  97         return ret;
  98 }
  99
 100 static int fuse_nfs_write(const char *path, const char *buf, size_t size,
 101        off_t offset, struct fuse_file_info *fi)
 102 {
 103         int ret = 0;
 104         struct nfsfh *nfsfh = (struct nfsfh *)fi->fh;
 105
 106         ret = nfs_pwrite(nfs, nfsfh, offset, size, discard_const(buf));
 107
 108         return ret;
 109 }
 110
 111 static int fuse_nfs_create(const char *path, mode_t mode, struct fuse_file_info *fi)
 112 {
 113         int ret = 0;
 114         struct nfsfh *nfsfh;
 115
 116         ret = nfs_creat(nfs, path, mode, &nfsfh);
 117         if (ret < 0) {
 118                 return ret;
 119         }
 120
 121         fi->fh = (uint64_t)nfsfh;
 122
 123         return ret;
 124 }
 125
 126 static int fuse_nfs_utime(const char *path, struct utimbuf *times)
 127 {
 128         int ret = 0;
 129
 130         ret = nfs_utime(nfs, path, times);
 131         if (ret < 0) {
 132                 return ret;
 133         }
 134
 135         return ret;
 136 }
 137
 138 static int fuse_nfs_unlink(const char *path)
 139 {
 140         int ret = 0;
 141
 142         ret = nfs_unlink(nfs, path);
 143         if (ret < 0) {
 144                 return ret;
 145         }
 146
 147         return ret;
 148 }
 149
 150 static int fuse_nfs_rmdir(const char *path)
 151 {
 152         int ret = 0;
 153
 154         ret = nfs_rmdir(nfs, path);
 155         if (ret < 0) {
 156                 return ret;
 157         }
 158
 159         return ret;
 160 }
 161
 162 static int fuse_nfs_mkdir(const char *path, mode_t mode)
 163 {
 164         int ret = 0;
 165
 166         ret = nfs_mkdir(nfs, path);
 167         if (ret < 0) {
 168                 return ret;
 169         }
 170         ret = nfs_chmod(nfs, path, mode);
 171         if (ret < 0) {
 172                 return ret;
 173         }
 174
 175         return ret;
 176 }
 177
 178 static struct fuse_operations nfs_oper = {
 179         .create         = fuse_nfs_create,
 180         .getattr        = fuse_nfs_getattr,
 181         .mkdir          = fuse_nfs_mkdir,
 182         .open           = fuse_nfs_open,
 183         .read           = fuse_nfs_read,
 184         .readdir        = fuse_nfs_readdir,
 185         .release        = fuse_nfs_release,
 186         .rmdir          = fuse_nfs_rmdir,
 187         .unlink         = fuse_nfs_unlink,
 188         .utime          = fuse_nfs_utime,
 189         .write          = fuse_nfs_write,
 190 };
 191
 192 void print_usage(char *name)
 193 {
 194         printf("Usage: %s [-?|--help] [-n|--nfs-share=nfs-url] [-m|--mountpoint=mountpoint]\n",
 195                 name);
 196         exit(0);
 197 }
 198
 199 int main(int argc, char *argv[])
 200 {
 201         int ret = 0;
 202         static struct option long_opts[] = {
 203                 { "help", no_argument, 0, '?' },
 204                 { "nfs-share", required_argument, 0, 'n' },
 205                 { "mountpoint", required_argument, 0, 'm' },
 206                 { NULL, 0, 0, 0 }
 207         };
 208         int c;
 209         int opt_idx = 0;
 210         char *url = NULL;
 211         char *mnt = NULL;
 212         char *server = NULL, *export = NULL, *strp;
 213         int fuse_nfs_argc = 5;
 214         char *fuse_nfs_argv[16] = {
 215                 "fuse-nfs",
 216                 "<export>",
 217                 "-oallow_other",
 218                 "-odefault_permissions",
 219                 "-omax_write=32768",
 220                 NULL,
 221                 NULL,
 222                 NULL,
 223                 NULL,
 224                 NULL,
 225                 NULL,
 226                 NULL,
 227                 NULL,
 228                 NULL,
 229                 NULL,
 230                 NULL,
 231         };
 232
 233         while ((c = getopt_long(argc, argv, "?hm:n:", long_opts,
 234                     &opt_idx)) > 0) {
 235                 switch (c) {
 236                 case 'h':
 237                 case '?':
 238                         print_usage(argv[0]);
 239                         return 0;
 240                 case 'm':
 241                         mnt = strdup(optarg);
 242                         break;
 243                 case 'n':
 244                         url = strdup(optarg);
 245                         break;
 246                 }
 247         }
 248
 249         if (url == NULL) {
 250                 fprintf(stderr, "-n was not specified.\n");
 251                 print_usage(argv[0]);
 252                 ret = 10;
 253                 goto finished;
 254         }
 255         if (mnt == NULL) {
 256                 fprintf(stderr, "-m was not specified.\n");
 257                 print_usage(argv[0]);
 258                 ret = 10;
 259                 goto finished;
 260         }
 261
 262
 263         if (strncmp(url, "nfs://", 6)) {
 264                 fprintf(stderr, "Invalid URL specified.\n");
 265                 ret = 10;
 266                 goto finished;
 267         }
 268         server = strdup(url + 6);
 269         if (server == NULL) {
 270                 fprintf(stderr, "Failed to strdup server string\n");
 271                 ret = 10;
 272                 goto finished;
 273         }
 274         if (server[0] == '/' || server[0] == '\0') {
 275                 fprintf(stderr, "Invalid server string.\n");
 276                 ret = 10;
 277                 goto finished;
 278         }
 279         strp = strchr(server, '/');
 280         if (strp == NULL) {
 281                 fprintf(stderr, "Invalid URL specified.\n");
 282                 ret = 10;
 283                 goto finished;
 284         }
 285         export = strdup(strp);
 286         if (export == NULL) {
 287                 fprintf(stderr, "Failed to strdup server string\n");
 288                 ret = 10;
 289                 goto finished;
 290         }
 291         if (export[0] != '/') {
 292                 fprintf(stderr, "Invalid export.\n");
 293                 ret = 10;
 294                 goto finished;
 295         }
 296         *strp = 0;
 297
 298         nfs = nfs_init_context();
 299         if (nfs == NULL) {
 300                 printf("failed to init context\n");
 301                 goto finished;
 302         }
 303
 304         ret = nfs_mount(nfs, server, export);
 305         if (ret != 0) {
 306                 printf("Failed to mount nfs share : %s\n", nfs_get_error(nfs));
 307                 goto finished;
 308         }
 309
 310
 311         fuse_nfs_argv[1] = mnt;
 312         return fuse_main(fuse_nfs_argc, fuse_nfs_argv, &nfs_oper, NULL);
 313
 314 finished:
 315         if (nfs != NULL) {
 316                 nfs_destroy_context(nfs);
 317         }
 318         free(server);
 319         free(export);
 320         free(url);
 321         free(mnt);
 322         return ret;
 323 }