1 /* This file contains file metadata retrieval and manipulation routines. 2 * 3 * The entry points into this file are: 4 * get_mode return a file's mode 5 * do_stat perform the STAT file system call 6 * do_chmod perform the CHMOD file system call 7 * do_utime perform the UTIME file system call 8 * 9 * Created: 10 * April 2009 (D.C. van Moolenbroek) 11 */ 12 13 #include "inc.h" 14 15 /*===========================================================================* 16 * get_mode * 17 *===========================================================================*/ 18 mode_t get_mode(struct inode *ino, int mode) 19 { 20 /* Return the mode for an inode, given the inode and the retrieved mode. 21 */ 22 23 mode &= S_IRWXU; 24 mode = mode | (mode >> 3) | (mode >> 6); 25 26 if (IS_DIR(ino)) 27 mode = S_IFDIR | (mode & sffs_params->p_dir_mask); 28 else 29 mode = S_IFREG | (mode & sffs_params->p_file_mask); 30 31 if (read_only) 32 mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH); 33 34 return mode; 35 } 36 37 /*===========================================================================* 38 * do_stat * 39 *===========================================================================*/ 40 int do_stat(ino_t ino_nr, struct stat *stat) 41 { 42 /* Retrieve inode status. 43 */ 44 struct inode *ino; 45 struct sffs_attr attr; 46 char path[PATH_MAX]; 47 int r; 48 49 /* Don't increase the inode refcount: it's already open anyway */ 50 if ((ino = find_inode(ino_nr)) == NULL) 51 return EINVAL; 52 53 attr.a_mask = SFFS_ATTR_MODE | SFFS_ATTR_SIZE | SFFS_ATTR_CRTIME | 54 SFFS_ATTR_ATIME | SFFS_ATTR_MTIME | SFFS_ATTR_CTIME; 55 56 if ((r = verify_inode(ino, path, &attr)) != OK) 57 return r; 58 59 stat->st_ino = ino_nr; 60 stat->st_mode = get_mode(ino, attr.a_mode); 61 stat->st_uid = sffs_params->p_uid; 62 stat->st_gid = sffs_params->p_gid; 63 stat->st_rdev = NO_DEV; 64 stat->st_size = attr.a_size; 65 stat->st_atimespec = attr.a_atime; 66 stat->st_mtimespec = attr.a_mtime; 67 stat->st_ctimespec = attr.a_ctime; 68 stat->st_birthtimespec = attr.a_crtime; 69 70 stat->st_blocks = stat->st_size / S_BLKSIZE; 71 if (stat->st_size % S_BLKSIZE != 0) 72 stat->st_blocks += 1; 73 74 stat->st_blksize = BLOCK_SIZE; 75 76 /* We could make this more accurate by iterating over directory inodes' 77 * children, counting how many of those are directories as well. 78 * It's just not worth it. 79 */ 80 stat->st_nlink = 0; 81 if (ino->i_parent != NULL) stat->st_nlink++; 82 if (IS_DIR(ino)) { 83 stat->st_nlink++; 84 if (HAS_CHILDREN(ino)) stat->st_nlink++; 85 } 86 87 return OK; 88 } 89 90 /*===========================================================================* 91 * do_chmod * 92 *===========================================================================*/ 93 int do_chmod(ino_t ino_nr, mode_t *mode) 94 { 95 /* Change file mode. 96 */ 97 struct inode *ino; 98 char path[PATH_MAX]; 99 struct sffs_attr attr; 100 int r; 101 102 if (read_only) 103 return EROFS; 104 105 if ((ino = find_inode(ino_nr)) == NULL) 106 return EINVAL; 107 108 if ((r = verify_inode(ino, path, NULL)) != OK) 109 return r; 110 111 /* Set the new file mode. */ 112 attr.a_mask = SFFS_ATTR_MODE; 113 attr.a_mode = *mode; /* no need to convert in this direction */ 114 115 if ((r = sffs_table->t_setattr(path, &attr)) != OK) 116 return r; 117 118 /* We have no idea what really happened. Query for the mode again. */ 119 if ((r = verify_path(path, ino, &attr, NULL)) != OK) 120 return r; 121 122 *mode = get_mode(ino, attr.a_mode); 123 124 return OK; 125 } 126 127 /*===========================================================================* 128 * do_utime * 129 *===========================================================================*/ 130 int do_utime(ino_t ino_nr, struct timespec *atime, struct timespec *mtime) 131 { 132 /* Set file times. 133 */ 134 struct inode *ino; 135 char path[PATH_MAX]; 136 struct sffs_attr attr; 137 int r; 138 139 if (read_only) 140 return EROFS; 141 142 if ((ino = find_inode(ino_nr)) == NULL) 143 return EINVAL; 144 145 if ((r = verify_inode(ino, path, NULL)) != OK) 146 return r; 147 148 attr.a_mask = 0; 149 150 switch (atime->tv_nsec) { 151 case UTIME_OMIT: /* do not touch */ 152 break; 153 case UTIME_NOW: 154 /* XXX VFS should have time() into ACTIME, for compat; we trust it! */ 155 atime->tv_nsec = 0; 156 /*FALLTHROUGH*/ 157 default: 158 attr.a_atime = *atime; 159 attr.a_mask |= SFFS_ATTR_ATIME; 160 break; 161 } 162 163 switch (mtime->tv_nsec) { 164 case UTIME_OMIT: /* do not touch */ 165 break; 166 case UTIME_NOW: 167 /* XXX VFS should have time() into MODTIME, for compat; we trust it! */ 168 mtime->tv_nsec = 0; 169 /*FALLTHROUGH*/ 170 default: 171 attr.a_mtime = *mtime; 172 attr.a_mask |= SFFS_ATTR_MTIME; 173 break; 174 } 175 176 return sffs_table->t_setattr(path, &attr); 177 } 178