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 xtype_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 xtype_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 xtype_have_attr(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 MIME_type *xtype_get(const char *path)
 118 {
 119         ssize_t size;
 120         gchar *buf;
 121         MIME_type *type = NULL;
 122
 123         RETURN_IF_IGNORED(type_from_path(path));
 124
 125         if (!dyn_getxattr)
 126                 return type_from_path(path);    /* Old libc */
 127
 128         size = dyn_getxattr(path, XTYPE_ATTR, "", 0);
 129         if (size > 0)
 130         {
 131                 int new_size;
 132
 133                 buf = g_new(gchar, size + 1);
 134                 new_size = dyn_getxattr(path, XTYPE_ATTR, buf, size);
 135
 136                 if (size == new_size)
 137                 {
 138                         buf[size] = '\0';
 139                         type = mime_type_lookup(buf);
 140                 }
 141                 g_free(buf);
 142
 143         }
 144         if (type)
 145                 return type;
 146
 147         /* Fall back to non-extended */
 148         return type_from_path(path);
 149 }
 150
 151 /* 0 on success */
 152 int xtype_set(const char *path, const MIME_type *type)
 153 {
 154         int res;
 155         gchar *ttext;
 156
 157         if(o_xattr_ignore.int_value)
 158         {
 159                 errno = ENOSYS;
 160                 return 1;
 161         }
 162
 163         if (!dyn_setxattr)
 164         {
 165                 errno = ENOSYS;
 166                 return 1; /* Set type failed */
 167         }
 168
 169         ttext = g_strdup_printf("%s/%s", type->media_type, type->subtype);
 170         res = dyn_setxattr(path, XTYPE_ATTR, ttext, strlen(ttext), 0);
 171         g_free(ttext);
 172
 173         return res;
 174 }
 175
 176 #elif defined(HAVE_ATTROPEN)
 177
 178 /* Solaris 9 implementation */
 179
 180 void xtype_init(void)
 181 {
 182         option_add_int(&o_xattr_ignore, "xattr_ignore", FALSE);
 183 }
 184
 185 int xtype_supported(const char *path)
 186 {
 187         RETURN_IF_IGNORED(FALSE);
 188 #ifdef _PC_XATTR_ENABLED
 189         if(!path)
 190                 return TRUE;
 191
 192         return pathconf(path, _PC_XATTR_ENABLED);
 193 #else
 194         return FALSE;
 195 #endif
 196 }
 197
 198 int xtype_have_attr(const char *path)
 199 {
 200         RETURN_IF_IGNORED(FALSE);
 201 #ifdef _PC_XATTR_EXISTS
 202         return pathconf(path, _PC_XATTR_EXISTS)>0;
 203 #else
 204         return FALSE;
 205 #endif
 206 }
 207
 208 MIME_type *xtype_get(const char *path)
 209 {
 210         int fd;
 211         char buf[1024];
 212         int nb;
 213         MIME_type *type=NULL;
 214
 215         RETURN_IF_IGNORED(type_from_path(path));
 216
 217 #ifdef _PC_XATTR_EXISTS
 218         if(!pathconf(path, _PC_XATTR_EXISTS))
 219                 return type_from_path(path);
 220 #endif
 221
 222         fd=attropen(path, XTYPE_ATTR, O_RDONLY);
 223
 224         if(fd>=0) {
 225                 nb=read(fd, buf, sizeof(buf));
 226                 if(nb>0) {
 227                         buf[nb]=0;
 228                         type=mime_type_lookup(buf);
 229                 }
 230                 close(fd);
 231         }
 232
 233         if(type)
 234                 return type;
 235
 236         /* Fall back to non-extended */
 237         return type_from_path(path);
 238 }
 239
 240 int xtype_set(const char *path, const MIME_type *type)
 241 {
 242         int fd;
 243         gchar *ttext;
 244         int nb;
 245
 246         if(o_xattr_ignore.int_value)
 247         {
 248                 errno = ENOSYS;
 249                 return 1;
 250         }
 251
 252         fd=attropen(path, XTYPE_ATTR, O_WRONLY|O_CREAT, 0644);
 253         if(fd>0) {
 254                 ttext=g_strdup_printf("%s/%s",
 255                                       type->media_type, type->subtype);
 256                 nb=write(fd, ttext, strlen(ttext));
 257                 if(nb==strlen(ttext))
 258                         ftruncate(fd, (off_t) nb);
 259                 g_free(ttext);
 260
 261                 close(fd);
 262
 263                 if(nb>0)
 264                         return 0;
 265         }
 266
 267         return 1; /* Set type failed */
 268 }
 269
 270 #else
 271 /* No extended attributes available */
 272
 273 void xtype_init(void)
 274 {
 275 }
 276
 277 int xtype_supported(const char *path)
 278 {
 279         return FALSE;
 280 }
 281
 282 int xtype_have_attr(const char *path)
 283 {
 284         return FALSE;
 285 }
 286
 287 MIME_type *xtype_get(const char *path)
 288 {
 289         /* Fall back to non-extended */
 290         return type_from_path(path);
 291 }
 292
 293 int xtype_set(const char *path, const MIME_type *type)
 294 {
 295         errno = ENOSYS;
 296         return 1; /* Set type failed */
 297 }
 298
 299 #endif
 300