ROX-Filer/src/xtypes.c

   1 /*
   2  * $Id$
   3  *
   4  * ROX-Filer, filer for the ROX desktop project
   5  * Copyright (C) 2005, the ROX-Filer team.
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the Free
   9  * Software Foundation; either version 2 of the License, or (at your option)
  10  * any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  19  * Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21
  22
  23 /*
  24  * xtypes.c - Extended filesystem attribute support for MIME types
  25  */
  26
  27 #include "config.h"
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <errno.h>
  31
  32 #include <unistd.h>
  33 #include <sys/types.h>
  34 #include <sys/stat.h>
  35 #include <fcntl.h>
  36
  37 #include <glib.h>
  38
  39 #include "global.h"
  40 #include "type.h"
  41 #include "xtypes.h"
  42 #include "options.h"
  43
  44 static Option o_xattr_ignore;
  45
  46 #define XTYPE_ATTR "user.mime_type"
  47
  48 #define RETURN_IF_IGNORED(val) if(o_xattr_ignore.int_value) return (val)
  49
  50 #if defined(HAVE_GETXATTR)
  51 /* Linux implementation */
  52
  53 #include <dlfcn.h>
  54
  55 static int (*dyn_setxattr)(const char *path, const char *name,
  56                      const void *value, size_t size, int flags) = NULL;
  57 static ssize_t (*dyn_getxattr)(const char *path, const char *name,
  58                          void *value, size_t size) = NULL;
  59 static ssize_t (*dyn_listxattr)(const char *path, char *list,
  60                          size_t size) = NULL;
  61
  62 void xattr_init(void)
  63 {
  64         void *libc;
  65
  66         libc = dlopen("libc.so.6", RTLD_LAZY | RTLD_NOLOAD);
  67         if (!libc)
  68                 return; /* Give up on xattr support */
  69
  70         dyn_setxattr = (void *) dlsym(libc, "setxattr");
  71         dyn_getxattr = (void *) dlsym(libc, "getxattr");
  72         dyn_listxattr = (void *) dlsym(libc, "listxattr");
  73
  74         option_add_int(&o_xattr_ignore, "xattr_ignore", FALSE);
  75 }
  76
  77 int xattr_supported(const char *path)
  78 {
  79         char buf[1];
  80         ssize_t nent;
  81
  82         RETURN_IF_IGNORED(FALSE);
  83
  84         if (!dyn_getxattr)
  85                 return FALSE;
  86
  87         if(path) {
  88                 errno=0;
  89                 nent=dyn_getxattr(path, XTYPE_ATTR, buf, sizeof(buf));
  90
  91                 if(nent<0 && errno==ENOTSUP)
  92                         return FALSE;
  93         }
  94
  95         return TRUE;
  96 }
  97
  98 int xattr_have(const char *path)
  99 {
 100         char buf[1];
 101         ssize_t nent;
 102
 103         RETURN_IF_IGNORED(FALSE);
 104
 105         if (!dyn_listxattr)
 106                 return FALSE;
 107
 108         errno=0;
 109         nent=dyn_listxattr(path, buf, sizeof(buf));
 110
 111         if(nent<0 && errno==ERANGE)
 112                 return TRUE;
 113
 114         return (nent>0);
 115 }
 116
 117 gchar *xattr_get(const char *path, const char *attr, int *len)
 118 {
 119         ssize_t size;
 120         gchar *buf;
 121
 122         RETURN_IF_IGNORED(NULL);
 123
 124         if (!dyn_getxattr)
 125                 return NULL;
 126
 127         size = dyn_getxattr(path, attr, "", 0);
 128         if (size > 0)
 129         {
 130                 int new_size;
 131
 132                 buf = g_new(gchar, size + 1);
 133                 new_size = dyn_getxattr(path, attr, buf, size);
 134
 135                 if(size == new_size)
 136                 {
 137                         buf[size] = '\0';
 138
 139                         if(len)
 140                                 *len=(int) size;
 141
 142                         return buf;
 143                 }
 144
 145                 g_free(buf);
 146         }
 147
 148         return NULL;
 149
 150 }
 151
 152 /* 0 on success */
 153 int xattr_set(const char *path, const char *attr,
 154               const char *value, int value_len)
 155 {
 156         if(o_xattr_ignore.int_value)
 157         {
 158                 errno = ENOSYS;
 159                 return 1;
 160         }
 161
 162         if (!dyn_setxattr)
 163         {
 164                 errno = ENOSYS;
 165                 return 1; /* Set attr failed */
 166         }
 167
 168         if(value && value_len<0)
 169                 value_len = strlen(value);
 170
 171         return dyn_setxattr(path, attr, value, value_len, 0);
 172 }
 173
 174
 175 #elif defined(HAVE_ATTROPEN)
 176
 177 /* Solaris 9 implementation */
 178
 179 void xattr_init(void)
 180 {
 181         option_add_int(&o_xattr_ignore, "xattr_ignore", FALSE);
 182 }
 183
 184 int xattr_supported(const char *path)
 185 {
 186         RETURN_IF_IGNORED(FALSE);
 187 #ifdef _PC_XATTR_ENABLED
 188         if(!path)
 189                 return TRUE;
 190
 191         return pathconf(path, _PC_XATTR_ENABLED);
 192 #else
 193         return FALSE;
 194 #endif
 195 }
 196
 197 int xattr_have(const char *path)
 198 {
 199         RETURN_IF_IGNORED(FALSE);
 200 #ifdef _PC_XATTR_EXISTS
 201         return pathconf(path, _PC_XATTR_EXISTS)>0;
 202 #else
 203         return FALSE;
 204 #endif
 205 }
 206
 207 #define MAX_ATTR_SIZE BUFSIZ
 208 gchar *xattr_get(const char *path, const char *attr, int *len)
 209 {
 210         int fd;
 211         char *buf=NULL;
 212         int nb;
 213
 214         RETURN_IF_IGNORED(NULL);
 215
 216 #ifdef _PC_XATTR_EXISTS
 217         if(!pathconf(path, _PC_XATTR_EXISTS))
 218                 return NULL;
 219 #endif
 220
 221         fd=attropen(path, attr, O_RDONLY);
 222
 223         if(fd>=0) {
 224                 buf = g_new(gchar, MAX_ATTR_SIZE);
 225                 nb=read(fd, buf, MAX_ATTR_SIZE);
 226                 if(nb>0) {
 227                         buf[nb]=0;
 228                 }
 229                 close(fd);
 230
 231                 if(len)
 232                         *len=nb;
 233         }
 234
 235         return buf;
 236 }
 237
 238 int xattr_set(const char *path, const char *attr,
 239               const char *value, int value_len)
 240 {
 241         int fd;
 242         int nb;
 243
 244         if(o_xattr_ignore.int_value)
 245         {
 246                 errno = ENOSYS;
 247                 return 1;
 248         }
 249
 250         if(value && value_len<0)
 251                 value_len = strlen(value);
 252
 253         fd=attropen(path, attr, O_WRONLY|O_CREAT, 0644);
 254         if(fd>0) {
 255
 256                 nb=write(fd, value, value_len);
 257                 if(nb==value_len)
 258                         ftruncate(fd, (off_t) nb);
 259
 260                 close(fd);
 261
 262                 if(nb>0)
 263                         return 0;
 264         }
 265
 266         return 1; /* Set type failed */
 267 }
 268
 269 #else
 270 /* No extended attributes available */
 271
 272 void xattr_init(void)
 273 {
 274 }
 275
 276 int xattr_supported(const char *path)
 277 {
 278         return FALSE;
 279 }
 280
 281 int xattr_have(const char *path)
 282 {
 283         return FALSE;
 284 }
 285
 286 gchar *xattr_get(const char *path, const char *attr, int *len)
 287 {
 288         /* Fall back to non-extended */
 289         return NULL;
 290 }
 291
 292 int xattr_set(const char *path, const char *attr,
 293               const char *value, int value_len)
 294 {
 295         errno = ENOSYS;
 296         return 1; /* Set type failed */
 297 }
 298
 299 #endif
 300
 301 MIME_type *xtype_get(const char *path)
 302 {
 303         MIME_type *type = NULL;
 304         gchar *buf;
 305         char *nl;
 306
 307         buf = xattr_get(path, XTYPE_ATTR, NULL);
 308
 309         if(buf)
 310         {
 311                 nl = strchr(buf, '\n');
 312                 if(nl)
 313                         *nl = 0;
 314                 type = mime_type_lookup(buf);
 315                 g_free(buf);
 316         }
 317         return type;
 318 }
 319
 320 int xtype_set(const char *path, const MIME_type *type)
 321 {
 322         int res;
 323         gchar *ttext;
 324
 325         if(o_xattr_ignore.int_value)
 326         {
 327                 errno = ENOSYS;
 328                 return 1;
 329         }
 330
 331         ttext = g_strdup_printf("%s/%s", type->media_type, type->subtype);
 332         res = xattr_set(path, XTYPE_ATTR, ttext, -1);
 333         g_free(ttext);
 334
 335         return res;
 336 }
 337