X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fheader.c;h=4924b505dfba8f6e455733ddcb0e67722ba70e9f;hp=c0518ecbabb820bec1933cc5c91d18aeb77173a7;hb=5944d11442d5df847c3393951a8563412d16e640;hpb=e8c3ca2d1d0cac3d64985b45a9f654d2029a7518 diff --git a/src/header.c b/src/header.c index c0518ecb..4924b505 100644 --- a/src/header.c +++ b/src/header.c @@ -29,7 +29,7 @@ #include "wimlib.h" #include "wimlib/assert.h" -#include "wimlib/buffer_io.h" +#include "wimlib/endianness.h" #include "wimlib/error.h" #include "wimlib/file_io.h" #include "wimlib/header.h" @@ -37,73 +37,100 @@ #include "wimlib/wim.h" #include +#include +#include +#ifdef HAVE_ALLOCA_H +# include +#else +# include +#endif -/* First 8 bytes in every WIM file. */ -static const u8 wim_magic_chars[WIM_MAGIC_LEN] = { - 'M', 'S', 'W', 'I', 'M', '\0', '\0', '\0' }; - -/* Reads the header from a WIM file. */ +/* + * Reads the header from a WIM file. + * + * @filename + * Name of the WIM file (for error/debug messages only), or NULL if reading + * directly from file descriptor. + * @in_fd + * File descriptor, positioned at offset 0, to read the header from. + * @hdr + * Structure to read the header into. + * + * Return values: + * WIMLIB_ERR_SUCCESS (0) + * WIMLIB_ERR_IMAGE_COUNT + * WIMLIB_ERR_INVALID_CHUNK_SIZE + * WIMLIB_ERR_INVALID_PART_NUMBER + * WIMLIB_ERR_NOT_A_WIM_FILE + * WIMLIB_ERR_READ + * WIMLIB_ERR_UNEXPECTED_END_OF_FILE + * WIMLIB_ERR_UNKNOWN_VERSION + */ int -read_header(const tchar *filename, int in_fd, - struct wim_header *hdr, int open_flags) +read_wim_header(const tchar *filename, struct filedes *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); + int ret; + tchar *pipe_str; - DEBUG("Reading WIM header from \"%"TS"\".", filename); + wimlib_assert(in_fd->offset == 0); - bytes_read = full_pread(in_fd, buf, WIM_HEADER_DISK_SIZE, 0); - - if (bytes_read != WIM_HEADER_DISK_SIZE) { - ERROR_WITH_ERRNO("\"%"TS"\": Error reading header", filename); - return WIMLIB_ERR_READ; + if (filename == NULL) { + pipe_str = alloca(40); + tsprintf(pipe_str, T("[fd %d]"), in_fd->fd); + filename = pipe_str; } - p = buf; - if (memcmp(p, wim_magic_chars, WIM_MAGIC_LEN)) { - ERROR("\"%"TS"\": Invalid magic characters in header", filename); - return WIMLIB_ERR_NOT_A_WIM_FILE; + BUILD_BUG_ON(sizeof(struct wim_header_disk) != WIM_HEADER_DISK_SIZE); + + DEBUG("Reading WIM header from \"%"TS"\"", filename); + + ret = full_read(in_fd, &disk_hdr, sizeof(disk_hdr)); + if (ret) + goto read_error; + + if (disk_hdr.magic != WIM_MAGIC) { + if (disk_hdr.magic == PWM_MAGIC) { + /* Pipable WIM: Use header at end instead, unless + * actually reading from a pipe. */ + if (!in_fd->is_pipe) { + lseek(in_fd->fd, -WIM_HEADER_DISK_SIZE, SEEK_END); + ret = full_read(in_fd, &disk_hdr, sizeof(disk_hdr)); + if (ret) + goto read_error; + } + } else { + ERROR("\"%"TS"\": Invalid magic characters in header", filename); + return WIMLIB_ERR_NOT_A_WIM_FILE; + } } + hdr->magic = disk_hdr.magic; - /* 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); - return WIMLIB_ERR_INVALID_HEADER_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; } - /* 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); + if (le32_to_cpu(disk_hdr.wim_flags) & WIM_HDR_FLAG_COMPRESS_LZMS) { + ERROR("\"%"TS"\": This WIM uses LZMS compression, " + "which is not supported by wimlib.", filename); + } 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 & WIM_HDR_FLAG_COMPRESSION)) { - ERROR("\"%"TS"\": Unexpected chunk size of %u! Ask the author to " - "implement support for other chunk sizes.", - filename, 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); + hdr->flags = le32_to_cpu(disk_hdr.wim_flags); + hdr->chunk_size = le32_to_cpu(disk_hdr.chunk_size); + 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", @@ -111,15 +138,7 @@ read_header(const tchar *filename, int in_fd, 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); @@ -130,98 +149,118 @@ read_header(const tchar *filename, int in_fd, return WIMLIB_ERR_IMAGE_COUNT; } - /* Byte 48 */ + 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; - 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); +read_error: + ERROR_WITH_ERRNO("\"%"TS"\": Error reading header", filename); + return ret; +} - /* Byte 120 */ +/* Writes the header for a WIM file at the specified offset. If the offset + * specified is the current one, the position is advanced by the size of the + * header. */ +int +write_wim_header_at_offset(const struct wim_header *hdr, struct filedes *out_fd, + off_t offset) +{ + struct wim_header_disk disk_hdr _aligned_attribute(8); + int ret; + + DEBUG("Writing %sWIM header at offset %"PRIu64, + ((hdr->magic == PWM_MAGIC) ? "pipable " : ""), + offset); + + disk_hdr.magic = hdr->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); + if (hdr->flags & WIM_HDR_FLAG_COMPRESSION) + disk_hdr.chunk_size = cpu_to_le32(hdr->chunk_size); + else + disk_hdr.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 (offset == out_fd->offset) + ret = full_write(out_fd, &disk_hdr, sizeof(disk_hdr)); + else + ret = full_pwrite(out_fd, &disk_hdr, sizeof(disk_hdr), offset); + if (ret) + ERROR_WITH_ERRNO("Failed to write WIM header"); + return ret; +} - p = get_u32(p, &hdr->boot_idx); +/* Writes the header for a WIM file at the output file descriptor's current + * offset. */ +int +write_wim_header(const struct wim_header *hdr, struct filedes *out_fd) +{ + return write_wim_header_at_offset(hdr, out_fd, out_fd->offset); +} - /* Byte 124 */ +/* Update just the wim_flags field. */ +int +write_wim_header_flags(u32 hdr_flags, struct filedes *out_fd) +{ + le32 flags = cpu_to_le32(hdr_flags); - p = get_resource_entry(p, &hdr->integrity); + return full_pwrite(out_fd, &flags, sizeof(flags), + offsetof(struct wim_header_disk, wim_flags)); +} - /* Byte 148 */ +int +set_wim_hdr_cflags(int ctype, struct wim_header *hdr) +{ + hdr->flags &= ~(WIM_HDR_FLAG_COMPRESSION | + WIM_HDR_FLAG_COMPRESS_LZX | + WIM_HDR_FLAG_COMPRESS_RESERVED | + WIM_HDR_FLAG_COMPRESS_XPRESS | + WIM_HDR_FLAG_COMPRESS_LZMS); + switch (ctype) { - /* 60 bytes of unused stuff. */ + case WIMLIB_COMPRESSION_TYPE_NONE: + return 0; - /* Byte 208 */ + case WIMLIB_COMPRESSION_TYPE_LZX: + hdr->flags |= WIM_HDR_FLAG_COMPRESSION | WIM_HDR_FLAG_COMPRESS_LZX; + return 0; - return 0; -} + case WIMLIB_COMPRESSION_TYPE_XPRESS: + hdr->flags |= WIM_HDR_FLAG_COMPRESSION | WIM_HDR_FLAG_COMPRESS_XPRESS; + return 0; -/* - * Writes the header for a WIM file. - * - * @hdr: A pointer to a struct wim_header structure that describes the header. - * @out_fd: The file descriptor to the WIM file, opened for writing. - * - * Returns zero on success, nonzero on failure. - */ -int -write_header(const struct wim_header *hdr, int out_fd) -{ - u8 buf[WIM_HEADER_DISK_SIZE]; - u8 *p; - 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)) { - ERROR_WITH_ERRNO("Failed to write WIM header"); - return WIMLIB_ERR_WRITE; + default: + return WIMLIB_ERR_INVALID_COMPRESSION_TYPE; } - DEBUG("Done writing WIM header"); - return 0; } /* * Initializes the header for a WIM file. */ int -init_header(struct wim_header *hdr, int ctype) +init_wim_header(struct wim_header *hdr, int ctype, u32 chunk_size) { memset(hdr, 0, sizeof(struct wim_header)); - switch (ctype) { - case WIMLIB_COMPRESSION_TYPE_NONE: - hdr->flags = 0; - break; - case WIMLIB_COMPRESSION_TYPE_LZX: - hdr->flags = WIM_HDR_FLAG_COMPRESSION | - WIM_HDR_FLAG_COMPRESS_LZX; - break; - case WIMLIB_COMPRESSION_TYPE_XPRESS: - hdr->flags = WIM_HDR_FLAG_COMPRESSION | - WIM_HDR_FLAG_COMPRESS_XPRESS; - break; - default: + hdr->magic = WIM_MAGIC; + if (set_wim_hdr_cflags(ctype, hdr)) { ERROR("Invalid compression type specified (%d)", ctype); return WIMLIB_ERR_INVALID_COMPRESSION_TYPE; } + hdr->chunk_size = chunk_size; hdr->total_parts = 1; hdr->part_number = 1; randomize_byte_array(hdr->guid, sizeof(hdr->guid)); @@ -246,11 +285,11 @@ struct hdr_flag hdr_flags[] = { {WIM_HDR_FLAG_COMPRESS_XPRESS, "COMPRESS_XPRESS"}, }; -/* Prints information from the header of the WIM file associated with @w. */ +/* API function documented in wimlib.h */ WIMLIBAPI void -wimlib_print_header(const WIMStruct *w) +wimlib_print_header(const WIMStruct *wim) { - const struct wim_header *hdr = &w->hdr; + const struct wim_header *hdr = &wim->hdr; tprintf(T("Magic Characters = MSWIM\\000\\000\\000\n")); tprintf(T("Header Size = %u\n"), WIM_HEADER_DISK_SIZE); @@ -261,12 +300,12 @@ wimlib_print_header(const WIMStruct *w) if (hdr_flags[i].flag & hdr->flags) tprintf(T(" WIM_HDR_FLAG_%s is set\n"), hdr_flags[i].name); - tprintf(T("Chunk Size = %u\n"), WIM_CHUNK_SIZE); + tprintf(T("Chunk Size = %u\n"), wim->hdr.chunk_size); tfputs (T("GUID = "), stdout); print_byte_field(hdr->guid, WIM_GID_LEN, stdout); tputchar(T('\n')); - tprintf(T("Part Number = %hu\n"), w->hdr.part_number); - tprintf(T("Total Parts = %hu\n"), w->hdr.total_parts); + tprintf(T("Part Number = %hu\n"), wim->hdr.part_number); + tprintf(T("Total Parts = %hu\n"), wim->hdr.total_parts); tprintf(T("Image Count = %u\n"), hdr->image_count); tprintf(T("Lookup Table Size = %"PRIu64"\n"), (u64)hdr->lookup_table_res_entry.size);