* along with wimlib; if not, see http://www.gnu.org/licenses/.
*/
-#include "wimlib_internal.h"
-#include "buffer_io.h"
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include "wimlib.h"
+#include "wimlib/assert.h"
+#include "wimlib/endianness.h"
+#include "wimlib/error.h"
+#include "wimlib/file_io.h"
+#include "wimlib/header.h"
+#include "wimlib/util.h"
+#include "wimlib/wim.h"
+
#include <limits.h>
+#include <string.h>
+
+/* WIM magic characters, translated to a single 64-bit little endian number. */
+#define WIM_MAGIC \
+ cpu_to_le64(((u64)'M' << 0) | \
+ ((u64)'S' << 8) | \
+ ((u64)'W' << 16) | \
+ ((u64)'I' << 24) | \
+ ((u64)'M' << 32) | \
+ ((u64)'\0' << 40) | \
+ ((u64)'\0' << 48) | \
+ ((u64)'\0' << 54))
+
+/* On-disk format of the WIM header. */
+struct wim_header_disk {
+
+ /* Magic characters "MSWIM\0\0\0" */
+ le64 magic;
+
+ /* Size of the WIM header, in bytes; WIM_HEADER_DISK_SIZE expected
+ * (currently the only supported value). */
+ u32 hdr_size;
+
+ /* Version of the WIM file; WIM_VERSION expected (currently the only
+ * supported value). */
+ u32 wim_version;
+
+ /* Flags for the WIM file (WIM_HDR_FLAG_*) */
+ u32 wim_flags;
+
+ /* Uncompressed chunk size of resources in the WIM. 0 if the WIM is
+ * uncompressed. If compressed, WIM_CHUNK_SIZE is expected (currently
+ * the only supported value). */
+ u32 chunk_size;
+
+ /* Globally unique identifier for the WIM file. Basically a bunch of
+ * random bytes. */
+ u8 guid[WIM_GID_LEN];
+
+ /* Number of this WIM part in the split WIM file, indexed from 1, or 1
+ * if the WIM is not split. */
+ u16 part_number;
+
+ /* Total number of parts of the split WIM file, or 1 if the WIM is not
+ * split. */
+ u16 total_parts;
+
+ /* Number of images in the WIM. */
+ u32 image_count;
+
+ /* Location and size of the WIM's lookup table. */
+ struct resource_entry_disk lookup_table_res_entry;
+
+ /* Location and size of the WIM's XML data. */
+ struct resource_entry_disk xml_data_res_entry;
-/* First 8 bytes in every WIM file. */
-static const u8 wim_magic_chars[WIM_MAGIC_LEN] = {
- 'M', 'S', 'W', 'I', 'M', '\0', '\0', '\0' };
+ /* Location and size of metadata resource for the bootable image of the
+ * WIM, or all zeroes if no image is bootable. */
+ struct resource_entry_disk boot_metadata_res_entry;
+
+ /* 1-based index of the bootable image of the WIM, or 0 if no image is
+ * bootable. */
+ u32 boot_idx;
+
+ /* Location and size of the WIM's integrity table, or all zeroes if the
+ * WIM has no integrity table.
+ *
+ * Note the integrity_table_res_entry here is 4-byte aligned even though
+ * it would ordinarily be 8-byte aligned--- hence, the _packed_attribute
+ * on the `struct wim_header_disk' is essential. */
+ struct resource_entry_disk integrity_table_res_entry;
+
+ /* Unused bytes. */
+ u8 unused[60];
+} _packed_attribute;
/* Reads the header from a WIM file. */
int
-read_header(const tchar *filename, int in_fd,
- struct wim_header *hdr, int open_flags)
+read_header(const tchar *filename, int in_fd, struct wim_header *hdr)
{
- size_t bytes_read;
- u8 buf[WIM_HEADER_DISK_SIZE];
- const void *p;
-
- u32 hdr_size;
- u32 wim_version;
- u32 chunk_size;
+ struct wim_header_disk disk_hdr _aligned_attribute(8);
- DEBUG("Reading WIM header from \"%"TS"\".", filename);
+ BUILD_BUG_ON(sizeof(struct wim_header_disk) != WIM_HEADER_DISK_SIZE);
- bytes_read = full_pread(in_fd, buf, WIM_HEADER_DISK_SIZE, 0);
+ DEBUG("Reading WIM header from \"%"TS"\"", filename);
- if (bytes_read != WIM_HEADER_DISK_SIZE) {
+ if (full_pread(in_fd, &disk_hdr, sizeof(disk_hdr), 0) != sizeof(disk_hdr)) {
ERROR_WITH_ERRNO("\"%"TS"\": Error reading header", filename);
return WIMLIB_ERR_READ;
}
- p = buf;
- if (memcmp(p, wim_magic_chars, WIM_MAGIC_LEN)) {
+ if (disk_hdr.magic != WIM_MAGIC) {
ERROR("\"%"TS"\": Invalid magic characters in header", filename);
return WIMLIB_ERR_NOT_A_WIM_FILE;
}
- /* Byte 8 */
- p = get_u32(p + 8, &hdr_size);
- if (hdr_size != WIM_HEADER_DISK_SIZE) {
- ERROR("\"%"TS"\": Header is %u bytes (expected %u bytes)",
- filename, hdr_size, WIM_HEADER_DISK_SIZE);
+ if (le32_to_cpu(disk_hdr.hdr_size) != sizeof(struct wim_header_disk)) {
+ ERROR("\"%"TS"\": Header size is invalid (%u bytes)",
+ filename, le32_to_cpu(disk_hdr.hdr_size));
return WIMLIB_ERR_INVALID_HEADER_SIZE;
}
- /* Byte 12 */
- p = get_u32(buf + WIM_MAGIC_LEN + sizeof(u32), &wim_version);
- if (wim_version != WIM_VERSION) {
+ if (le32_to_cpu(disk_hdr.wim_version) != WIM_VERSION) {
ERROR("\"%"TS"\": The WIM header says the WIM version is %u, "
"but wimlib only knows about version %u",
- filename, wim_version, WIM_VERSION);
+ filename, le32_to_cpu(disk_hdr.wim_version), WIM_VERSION);
return WIMLIB_ERR_UNKNOWN_VERSION;
}
- p = get_u32(p, &hdr->flags);
- p = get_u32(p, &chunk_size);
- if (chunk_size != WIM_CHUNK_SIZE &&
+ hdr->flags = le32_to_cpu(disk_hdr.wim_flags);
+ if (le32_to_cpu(disk_hdr.chunk_size) != WIM_CHUNK_SIZE &&
(hdr->flags & WIM_HDR_FLAG_COMPRESSION)) {
ERROR("\"%"TS"\": Unexpected chunk size of %u! Ask the author to "
"implement support for other chunk sizes.",
- filename, chunk_size);
+ filename, le32_to_cpu(disk_hdr.chunk_size));
ERROR("(Or it might just be that the WIM header is invalid.)");
return WIMLIB_ERR_INVALID_CHUNK_SIZE;
}
- p = get_bytes(p, WIM_GID_LEN, hdr->guid);
- p = get_u16(p, &hdr->part_number);
- p = get_u16(p, &hdr->total_parts);
+ memcpy(hdr->guid, disk_hdr.guid, WIM_GID_LEN);
+
+ hdr->part_number = le16_to_cpu(disk_hdr.part_number);
+ hdr->total_parts = le16_to_cpu(disk_hdr.total_parts);
- if (hdr->total_parts == 0 ||
- hdr->part_number == 0 ||
+ if (hdr->total_parts == 0 || hdr->part_number == 0 ||
hdr->part_number > hdr->total_parts)
{
ERROR("\"%"TS"\": Invalid WIM part number: %hu of %hu",
return WIMLIB_ERR_INVALID_PART_NUMBER;
}
- if (!(open_flags & WIMLIB_OPEN_FLAG_SPLIT_OK) &&
- hdr->total_parts != 1)
- {
- ERROR("\"%"TS"\": This WIM is part %u of a %u-part WIM",
- filename, hdr->part_number, hdr->total_parts);
- return WIMLIB_ERR_SPLIT_UNSUPPORTED;
- }
-
- p = get_u32(p, &hdr->image_count);
+ hdr->image_count = le32_to_cpu(disk_hdr.image_count);
DEBUG("part_number = %u, total_parts = %u, image_count = %u",
hdr->part_number, hdr->total_parts, hdr->image_count);
return WIMLIB_ERR_IMAGE_COUNT;
}
- /* Byte 48 */
-
- p = get_resource_entry(p, &hdr->lookup_table_res_entry);
- p = get_resource_entry(p, &hdr->xml_res_entry);
- p = get_resource_entry(p, &hdr->boot_metadata_res_entry);
-
- /* Byte 120 */
-
- p = get_u32(p, &hdr->boot_idx);
-
- /* Byte 124 */
-
- p = get_resource_entry(p, &hdr->integrity);
-
- /* Byte 148 */
-
- /* 60 bytes of unused stuff. */
-
- /* Byte 208 */
-
+ get_resource_entry(&disk_hdr.lookup_table_res_entry, &hdr->lookup_table_res_entry);
+ get_resource_entry(&disk_hdr.xml_data_res_entry, &hdr->xml_res_entry);
+ get_resource_entry(&disk_hdr.boot_metadata_res_entry, &hdr->boot_metadata_res_entry);
+ hdr->boot_idx = le32_to_cpu(disk_hdr.boot_idx);
+ get_resource_entry(&disk_hdr.integrity_table_res_entry, &hdr->integrity);
return 0;
}
int
write_header(const struct wim_header *hdr, int out_fd)
{
- u8 buf[WIM_HEADER_DISK_SIZE];
- u8 *p;
+ struct wim_header_disk disk_hdr _aligned_attribute(8);
DEBUG("Writing WIM header.");
- p = put_bytes(buf, WIM_MAGIC_LEN, wim_magic_chars);
- p = put_u32(p, WIM_HEADER_DISK_SIZE);
- p = put_u32(p, WIM_VERSION);
- p = put_u32(p, hdr->flags);
- p = put_u32(p, (hdr->flags & WIM_HDR_FLAG_COMPRESSION) ?
- WIM_CHUNK_SIZE : 0);
- /* Byte 24 */
-
- p = put_bytes(p, WIM_GID_LEN, hdr->guid);
- p = put_u16(p, hdr->part_number);
-
- /* Byte 40 */
-
- p = put_u16(p, hdr->total_parts);
- p = put_u32(p, hdr->image_count);
- p = put_resource_entry(p, &hdr->lookup_table_res_entry);
- p = put_resource_entry(p, &hdr->xml_res_entry);
- p = put_resource_entry(p, &hdr->boot_metadata_res_entry);
- p = put_u32(p, hdr->boot_idx);
- p = put_resource_entry(p, &hdr->integrity);
- p = put_zeroes(p, WIM_UNUSED_LEN);
- wimlib_assert(p - buf == sizeof(buf));
-
- if (full_pwrite(out_fd, buf, sizeof(buf), 0) != sizeof(buf)) {
+ disk_hdr.magic = WIM_MAGIC;
+ disk_hdr.hdr_size = cpu_to_le32(sizeof(struct wim_header_disk));
+ disk_hdr.wim_version = cpu_to_le32(WIM_VERSION);
+ disk_hdr.wim_flags = cpu_to_le32(hdr->flags);
+ disk_hdr.chunk_size = cpu_to_le32((hdr->flags & WIM_HDR_FLAG_COMPRESSION) ?
+ WIM_CHUNK_SIZE : 0);
+ memcpy(disk_hdr.guid, hdr->guid, WIM_GID_LEN);
+
+ disk_hdr.part_number = cpu_to_le16(hdr->part_number);
+ disk_hdr.total_parts = cpu_to_le16(hdr->total_parts);
+ disk_hdr.image_count = cpu_to_le32(hdr->image_count);
+ put_resource_entry(&hdr->lookup_table_res_entry, &disk_hdr.lookup_table_res_entry);
+ put_resource_entry(&hdr->xml_res_entry, &disk_hdr.xml_data_res_entry);
+ put_resource_entry(&hdr->boot_metadata_res_entry, &disk_hdr.boot_metadata_res_entry);
+ disk_hdr.boot_idx = cpu_to_le32(hdr->boot_idx);
+ put_resource_entry(&hdr->integrity, &disk_hdr.integrity_table_res_entry);
+ memset(disk_hdr.unused, 0, sizeof(disk_hdr.unused));
+
+ if (full_pwrite(out_fd, &disk_hdr, sizeof(disk_hdr), 0) != sizeof(disk_hdr)) {
ERROR_WITH_ERRNO("Failed to write WIM header");
return WIMLIB_ERR_WRITE;
}
return 0;
}
+/* Update just the wim_flags field. */
+int
+write_header_flags(u32 hdr_flags, int out_fd)
+{
+ le32 flags = cpu_to_le32(hdr_flags);
+ if (full_pwrite(out_fd, &flags, sizeof(flags),
+ offsetof(struct wim_header_disk, wim_flags)) != sizeof(flags))
+ {
+ return WIMLIB_ERR_WRITE;
+ } else {
+ return 0;
+ }
+
+}
+
+/* Update just the part_number and total_parts fields. */
+int
+write_header_part_data(u16 part_number, u16 total_parts, int out_fd)
+{
+ le16 part_data[2] = {
+ cpu_to_le16(part_number),
+ cpu_to_le16(total_parts),
+ };
+ if (full_pwrite(out_fd, &part_data, sizeof(part_data),
+ offsetof(struct wim_header_disk, part_number)) != sizeof(part_data))
+ {
+ return WIMLIB_ERR_WRITE;
+ } else {
+ return 0;
+ }
+}
+
/*
* Initializes the header for a WIM file.
*/
git://wimlib.net / wimlib / blobdiff