diff options
Diffstat (limited to 'cpukit/libfs/src/imfs/imfs_load_tar.c')
| -rw-r--r-- | cpukit/libfs/src/imfs/imfs_load_tar.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/cpukit/libfs/src/imfs/imfs_load_tar.c b/cpukit/libfs/src/imfs/imfs_load_tar.c new file mode 100644 index 0000000000..3cb3c4e195 --- /dev/null +++ b/cpukit/libfs/src/imfs/imfs_load_tar.c @@ -0,0 +1,186 @@ +/* + * COPYRIGHT (c) 1989-2010. + * On-Line Applications Research Corporation (OAR). + * + * 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. + * + * $Id$ + */ + +#if HAVE_CONFIG_H +#include "config.h" +#endif + +/* + * This file implements the "mount" procedure for tar-based IMFS + * extensions. The TAR is not actually mounted under the IMFS. + * Directories from the TAR file are created as usual in the IMFS. + * File entries are created as IMFS_LINEAR_FILE nodes with their nods + * pointing to addresses in the TAR image. + */ + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <tar.h> + +#include <string.h> + +#include <rtems.h> +#include <rtems/libio_.h> +#include <rtems/imfs.h> +#include <rtems/untar.h> + +/* + * TAR file format: + * + * Offset Length Contents + * 0 100 bytes File name ('\0' terminated, 99 maxmum length) + * 100 8 bytes File mode (in octal ascii) + * 108 8 bytes User ID (in octal ascii) + * 116 8 bytes Group ID (in octal ascii) + * 124 12 bytes File size (s) (in octal ascii) + * 136 12 bytes Modify time (in octal ascii) + * 148 8 bytes Header checksum (in octal ascii) + * 156 1 bytes Link flag + * 157 100 bytes Linkname ('\0' terminated, 99 maxmum length) + * 257 8 bytes Magic PAX ("ustar\0" + 2 bytes padding) + * 257 8 bytes Magic GNU tar ("ustar \0") + * 265 32 bytes User name ('\0' terminated, 31 maxmum length) + * 297 32 bytes Group name ('\0' terminated, 31 maxmum length) + * 329 8 bytes Major device ID (in octal ascii) + * 337 8 bytes Minor device ID (in octal ascii) + * 345 167 bytes Padding + * 512 (s+p)bytes File contents (s+p) := (((s) + 511) & ~511), + * round up to 512 bytes + * + * Checksum: + * int i, sum; + * char* header = tar_header_pointer; + * sum = 0; + * for(i = 0; i < 512; i++) + * sum += 0xFF & header[i]; + */ + +#define MAX_NAME_FIELD_SIZE 99 + +#define MIN(a,b) ((a)>(b)?(b):(a)) + +/* + * rtems_tarfs_load + * + * Here we create the mountpoint directory and load the tarfs at + * that node. Once the IMFS has been mounted, we work through the + * tar image and perform as follows: + * - For directories, simply call mkdir(). The IMFS creates nodes as + * needed. + * - For files, we make our own calls to IMFS eval_for_make and + * create_node. + */ +int rtems_tarfs_load( + char *mountpoint, + uint8_t *tar_image, + size_t tar_size +) +{ + rtems_filesystem_location_info_t root_loc; + rtems_filesystem_location_info_t loc; + const char *hdr_ptr; + char filename[100]; + char full_filename[256]; + int hdr_chksum; + unsigned char linkflag; + unsigned long file_size; + unsigned long file_mode; + int offset; + unsigned long nblocks; + IMFS_jnode_t *node; + int status; + + status = rtems_filesystem_evaluate_path( + mountpoint, + strlen(mountpoint), + 0, + &root_loc, + 0 + ); + if (status != 0) + return -1; + + if (root_loc.ops != &IMFS_ops && root_loc.ops != &fifoIMFS_ops) + return -1; + + /* + * Create an IMFS node structure pointing to tar image memory. + */ + offset = 0; + while (1) { + if (offset + 512 > tar_size) + break; + + /* + * Read a header. + */ + hdr_ptr = (char *) &tar_image[offset]; + offset += 512; + if (strncmp(&hdr_ptr[257], "ustar", 5)) + break; + + strncpy(filename, hdr_ptr, MAX_NAME_FIELD_SIZE); + filename[MAX_NAME_FIELD_SIZE] = '\0'; + + linkflag = hdr_ptr[156]; + file_mode = _rtems_octal2ulong(&hdr_ptr[100], 8); + file_size = _rtems_octal2ulong(&hdr_ptr[124], 12); + hdr_chksum = _rtems_octal2ulong(&hdr_ptr[148], 8); + + if (_rtems_tar_header_checksum(hdr_ptr) != hdr_chksum) + break; + + /* + * Generate an IMFS node depending on the file type. + * - For directories, just create directories as usual. IMFS + * will take care of the rest. + * - For files, create a file node with special tarfs properties. + */ + if (linkflag == DIRTYPE) { + strcpy(full_filename, mountpoint); + if (full_filename[strlen(full_filename)-1] != '/') + strcat(full_filename, "/"); + strcat(full_filename, filename); + mkdir(full_filename, S_IRWXU | S_IRWXG | S_IRWXO); + } + /* + * Create a LINEAR_FILE node + * + * NOTE: Coverity Id 20 reports this as a leak. + * While technically not a leak, it indicated that + * IMFS_create_node was ONLY passed a NULL when we created the + * root node. We added a new IMFS_create_root_node() so this + * path no longer existed. The result was simpler code which + * should not have this path. + */ + else if (linkflag == REGTYPE) { + const char *name; + + loc = root_loc; + if (IMFS_evaluate_for_make(filename, &loc, &name) == 0) { + node = IMFS_create_node( + &loc, + IMFS_LINEAR_FILE, (char *)name, + (file_mode & (S_IRWXU | S_IRWXG | S_IRWXO)) | S_IFREG, + NULL + ); + node->info.linearfile.size = file_size; + node->info.linearfile.direct = &tar_image[offset]; + } + + nblocks = (((file_size) + 511) & ~511) / 512; + offset += 512 * nblocks; + } + } + return status; +} + |