diff options
Diffstat (limited to 'cpukit/libfs/src/rfs/rtems-rfs-link.c')
| -rw-r--r-- | cpukit/libfs/src/rfs/rtems-rfs-link.c | 458 |
1 files changed, 458 insertions, 0 deletions
diff --git a/cpukit/libfs/src/rfs/rtems-rfs-link.c b/cpukit/libfs/src/rfs/rtems-rfs-link.c new file mode 100644 index 0000000000..27a08153b9 --- /dev/null +++ b/cpukit/libfs/src/rfs/rtems-rfs-link.c @@ -0,0 +1,458 @@ +/* + * COPYRIGHT (c) 2010 Chris Johns <chrisj@rtems.org> + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.com/license/LICENSE. + * + * $Id$ + */ +/** + * @file + * + * @ingroup rtems-rfs + * + * RTEMS File Systems Link Routines. + * + * These functions manage links. A link is the addition of a directory entry in + * a parent directory and incrementing the links count in the inode. + */ + +#if HAVE_CONFIG_H +#include "config.h" +#endif + +#include <inttypes.h> + +#include <rtems/rfs/rtems-rfs-block.h> +#include <rtems/rfs/rtems-rfs-buffer.h> +#include <rtems/rfs/rtems-rfs-file-system.h> +#include <rtems/rfs/rtems-rfs-trace.h> +#include <rtems/rfs/rtems-rfs-dir.h> +#include <rtems/rfs/rtems-rfs-dir-hash.h> +#include <rtems/rfs/rtems-rfs-link.h> + +int +rtems_rfs_link (rtems_rfs_file_system* fs, + const char* name, + int length, + rtems_rfs_ino parent, + rtems_rfs_ino target, + bool link_dir) +{ + rtems_rfs_inode_handle parent_inode; + rtems_rfs_inode_handle target_inode; + uint16_t links; + int rc; + + if (rtems_rfs_trace (RTEMS_RFS_TRACE_LINK)) + { + int c; + printf ("rtems-rfs: link: parent(%" PRIu32 ") -> ", parent); + for (c = 0; c < length; c++) + printf ("%c", name[c]); + printf ("(%" PRIu32 ")\n", target); + } + + rc = rtems_rfs_inode_open (fs, target, &target_inode, true); + if (rc) + return rc; + + /* + * If the target inode is a directory and we cannot link directories + * return a not supported error code. + */ + if (!link_dir && S_ISDIR (rtems_rfs_inode_get_mode (&target_inode))) + { + rtems_rfs_inode_close (fs, &target_inode); + return ENOTSUP; + } + + rc = rtems_rfs_inode_open (fs, parent, &parent_inode, true); + if (rc) + { + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + rc = rtems_rfs_dir_add_entry (fs, &parent_inode, name, length, target); + if (rc > 0) + { + rtems_rfs_inode_close (fs, &parent_inode); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + links = rtems_rfs_inode_get_links (&target_inode) + 1; + rtems_rfs_inode_set_links (&target_inode, links); + + rc = rtems_rfs_inode_time_stamp_now (&parent_inode, true, true); + if (rc > 0) + { + rtems_rfs_inode_close (fs, &parent_inode); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + rc = rtems_rfs_inode_close (fs, &parent_inode); + if (rc > 0) + { + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + rc = rtems_rfs_inode_close (fs, &target_inode); + + return rc; +} + +int +rtems_rfs_unlink (rtems_rfs_file_system* fs, + rtems_rfs_ino parent, + rtems_rfs_ino target, + uint32_t doff, + rtems_rfs_unlink_dir dir_mode) +{ + rtems_rfs_inode_handle parent_inode; + rtems_rfs_inode_handle target_inode; + uint16_t links; + bool dir; + int rc; + + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: unlink: parent(%" PRIu32 ") -X-> (%" PRIu32 ")\n", parent, target); + + rc = rtems_rfs_inode_open (fs, target, &target_inode, true); + if (rc) + return rc; + + /* + * If a directory process the unlink mode. + */ + + dir = RTEMS_RFS_S_ISDIR (rtems_rfs_inode_get_mode (&target_inode)); + if (dir) + { + switch (dir_mode) + { + case rtems_rfs_unlink_dir_denied: + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: link is a directory\n"); + rtems_rfs_inode_close (fs, &target_inode); + return EISDIR; + + case rtems_rfs_unlink_dir_if_empty: + rc = rtems_rfs_dir_empty (fs, &target_inode); + if (rc > 0) + { + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: dir-empty: %d: %s\n", rc, strerror (rc)); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + break; + + default: + break; + } + } + + rc = rtems_rfs_inode_open (fs, parent, &parent_inode, true); + if (rc) + { + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: link: inode-open failed: %d: %s\n", + rc, strerror (rc)); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + rc = rtems_rfs_dir_del_entry (fs, &parent_inode, target, doff); + if (rc > 0) + { + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: unlink: dir-del failed: %d: %s\n", + rc, strerror (rc)); + rtems_rfs_inode_close (fs, &parent_inode); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + links = rtems_rfs_inode_get_links (&target_inode); + + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: unlink: target:%" PRIu32 " links:%u\n", target, links); + + if (links > 1) + { + links--; + rtems_rfs_inode_set_links (&target_inode, links); + } + else + { + /* + * Erasing the inode releases all blocks attached to it. + */ + rc = rtems_rfs_inode_delete (fs, &target_inode); + if (rc > 0) + { + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: unlink: inode-del failed: %d: %s\n", + rc, strerror (rc)); + rtems_rfs_inode_close (fs, &parent_inode); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + if (dir) + { + links = rtems_rfs_inode_get_links (&parent_inode); + if (links > 1) + links--; + rtems_rfs_inode_set_links (&parent_inode, links); + } + } + + rc = rtems_rfs_inode_time_stamp_now (&parent_inode, true, true); + if (rc > 0) + { + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: link: inode-time-stamp failed: %d: %s\n", + rc, strerror (rc)); + rtems_rfs_inode_close (fs, &parent_inode); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + rc = rtems_rfs_inode_close (fs, &parent_inode); + if (rc > 0) + { + if (rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: link: parent inode-close failed: %d: %s\n", + rc, strerror (rc)); + rtems_rfs_inode_close (fs, &target_inode); + return rc; + } + + rc = rtems_rfs_inode_close (fs, &target_inode); + + if ((rc > 0) && rtems_rfs_trace (RTEMS_RFS_TRACE_UNLINK)) + printf ("rtems-rfs: link: target inode-close failed: %d: %s\n", + rc, strerror (rc)); + + return rc; +} + +int +rtems_rfs_symlink (rtems_rfs_file_system* fs, + const char* name, + int length, + const char* link, + int link_length, + uid_t uid, + gid_t gid, + rtems_rfs_ino parent) +{ + rtems_rfs_inode_handle inode; + rtems_rfs_ino ino; + int rc; + + if (rtems_rfs_trace (RTEMS_RFS_TRACE_SYMLINK)) + { + int c; + printf ("rtems-rfs: symlink: parent:%" PRIu32 " name:", parent); + for (c = 0; c < length; c++) + printf ("%c", name[c]); + printf (" link:"); + for (c = 0; c < link_length; c++) + printf ("%c", link[c]); + } + + if (link_length >= rtems_rfs_fs_block_size (fs)) + return ENAMETOOLONG; + + rc = rtems_rfs_inode_create (fs, parent, name, strlen (name), + RTEMS_RFS_S_SYMLINK, + 1, uid, gid, &ino); + if (rc > 0) + return rc; + + rc = rtems_rfs_inode_open (fs, ino, &inode, true); + if (rc > 0) + return rc; + + /* + * If the link length is less than the length of data union in the inode + * place the link into the data area else allocate a block and write the link + * to that. + */ + if (link_length < RTEMS_RFS_INODE_DATA_NAME_SIZE) + { + memset (inode.node->data.name, 0, RTEMS_RFS_INODE_DATA_NAME_SIZE); + memcpy (inode.node->data.name, link, link_length); + rtems_rfs_inode_set_block_count (&inode, 0); + } + else + { + rtems_rfs_block_map map; + rtems_rfs_block_no block; + rtems_rfs_buffer_handle buffer; + uint8_t* data; + + rc = rtems_rfs_block_map_open (fs, &inode, &map); + if (rc > 0) + { + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_block_map_grow (fs, &map, 1, &block); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_buffer_handle_open (fs, &buffer); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_buffer_handle_request (fs, &buffer, block, false); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + data = rtems_rfs_buffer_data (&buffer); + + memset (data, 0xff, rtems_rfs_fs_block_size (fs)); + memcpy (data, link, link_length); + + rc = rtems_rfs_buffer_handle_close (fs, &buffer); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_block_map_close (fs, &map); + if (rc > 0) + { + rtems_rfs_inode_close (fs, &inode); + return rc; + } + } + + rtems_rfs_inode_set_block_offset (&inode, link_length); + + rc = rtems_rfs_inode_close (fs, &inode); + + return rc; +} + +int +rtems_rfs_symlink_read (rtems_rfs_file_system* fs, + rtems_rfs_ino link, + char* path, + size_t size, + size_t* length) +{ + rtems_rfs_inode_handle inode; + int rc; + + if (rtems_rfs_trace (RTEMS_RFS_TRACE_SYMLINK_READ)) + printf ("rtems-rfs: symlink-read: link:%" PRIu32 "\n", link); + + rc = rtems_rfs_inode_open (fs, link, &inode, true); + if (rc) + return rc; + + if (!RTEMS_RFS_S_ISLNK (rtems_rfs_inode_get_mode (&inode))) + { + rtems_rfs_inode_close (fs, &inode); + return EINVAL; + } + + *length = rtems_rfs_inode_get_block_offset (&inode); + + if (size < *length) + { + rtems_rfs_inode_close (fs, &inode); + return EINVAL; + } + + if (rtems_rfs_inode_get_block_count (&inode) == 0) + { + memcpy (path, inode.node->data.name, *length); + } + else + { + rtems_rfs_block_map map; + rtems_rfs_block_no block; + rtems_rfs_buffer_handle buffer; + char* data; + + rc = rtems_rfs_block_map_open (fs, &inode, &map); + if (rc > 0) + { + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_block_map_seek (fs, &map, 0, &block); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_buffer_handle_open (fs, &buffer); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_buffer_handle_request (fs, &buffer, block, false); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + data = rtems_rfs_buffer_data (&buffer); + memcpy (path, data, *length); + + rc = rtems_rfs_buffer_handle_close (fs, &buffer); + if (rc > 0) + { + rtems_rfs_block_map_close (fs, &map); + rtems_rfs_inode_close (fs, &inode); + return rc; + } + + rc = rtems_rfs_block_map_close (fs, &map); + if (rc > 0) + { + rtems_rfs_inode_close (fs, &inode); + return rc; + } + } + + path[*length] = '\0'; + + rc = rtems_rfs_inode_close (fs, &inode); + + return rc; +} |