-
-
-/* Used for buffering FILE IO */
-#define BUFFER_SIZE 4096
-
-/*
- * Copies bytes between two file streams.
- *
- * Copies @len bytes from @in to @out, at the current position in @out, and at
- * an offset of @in_offset in @in.
- */
-int copy_between_files(FILE *in, off_t in_offset, FILE *out, size_t len)
-{
- u8 buf[BUFFER_SIZE];
- size_t n;
-
- if (fseeko(in, in_offset, SEEK_SET) != 0) {
- ERROR("Failed to seek to byte %"PRIu64" of input file: %m\n",
- in_offset);
- return WIMLIB_ERR_READ;
- }
- /* To reduce memory usage and improve speed, read and write BUFFER_SIZE
- * bytes at a time. */
- while (len != 0) {
- n = min(len, BUFFER_SIZE);
- if (fread(buf, 1, n, in) != n) {
- if (feof(in)) {
- ERROR("Unexpected EOF when copying data "
- "between files\n");
- } else {
- ERROR("Error copying data between files: %m\n");
- }
- return WIMLIB_ERR_READ;
- }
-
- if (fwrite(buf, 1, n, out) != n) {
- ERROR("Error copying data between files: %m\n");
- return WIMLIB_ERR_WRITE;
- }
- len -= n;
- }
- return 0;
-}
-
-
-/*
- * Uncompresses a WIM file resource and writes it uncompressed to a file stream.
- *
- * @in: The file stream that contains the file resource.
- * @size: The size of the resource in the input file.
- * @original_size: The original (uncompressed) size of the resource.
- * @offset: The offset of the start of the resource in @in.
- * @input_ctype: The compression type of the resource in @in.
- * @out: The file stream to write the file resource to.
- */
-static int uncompress_resource(FILE *in, u64 size, u64 original_size,
- off_t offset, int input_ctype, FILE *out)
-{
- int ret;
- u8 buf[WIM_CHUNK_SIZE];
- /* Determine how many compressed chunks the file is divided into. */
- u64 num_chunks;
- u64 i;
- u64 uncompressed_offset;
- u64 uncompressed_chunk_size;
-
- num_chunks = (original_size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE;
-
- for (i = 0; i < num_chunks; i++) {
-
- uncompressed_offset = i * WIM_CHUNK_SIZE;
- uncompressed_chunk_size = min(WIM_CHUNK_SIZE,
- original_size - uncompressed_offset);
-
- ret = read_resource(in, size, original_size, offset, input_ctype,
- uncompressed_chunk_size,
- uncompressed_offset, buf);
- if (ret != 0)
- return ret;
-
- if (fwrite(buf, 1, uncompressed_chunk_size, out) !=
- uncompressed_chunk_size) {
- ERROR("Failed to write file resource: %m\n");
- return WIMLIB_ERR_WRITE;
- }
- }
- return 0;
-}
-
-/*
- * Transfers a file resource between two files, writing it compressed. The file
- * resource in the input file may be either compressed or uncompressed.
- * Alternatively, the input resource may be in-memory, but it must be
- * uncompressed.
- *
- * @in: The file stream that contains the file resource. Ignored
- * if uncompressed_resource != NULL.
- * @uncompressed_resource: If this pointer is not NULL, it points to an
- * array of @original_size bytes that are
- * the uncompressed input resource.
- * @size: The size of the resource in the input file.
- * @original_size: The original (uncompressed) size of the resource.
- * @offset: The offset of the start of the resource in @in. Ignored
- * if uncompressed_resource != NULL.
- * @input_ctype: The compression type of the resource in @in. Ignored if
- * uncompressed_resource != NULL.
- * @out: The file stream to write the file resource to.
- * @output_type: The compression type to use when writing the resource to
- * @out.
- * @new_size_ret: A location into which the new compressed size of the file
- * resource in returned.
- */
-static int recompress_resource(FILE *in, const u8 uncompressed_resource[],
- u64 size, u64 original_size,
- off_t offset, int input_ctype, FILE *out,
- int output_ctype, u64 *new_size_ret)
-{
- int ret;
- int (*compress)(const void *, uint, void *, uint *);
- if (output_ctype == WIM_COMPRESSION_TYPE_LZX)
- compress = lzx_compress;
- else
- compress = xpress_compress;
-
- u8 uncompressed_buf[WIM_CHUNK_SIZE];
- u8 compressed_buf[WIM_CHUNK_SIZE - 1];
-
- /* Determine how many compressed chunks the file needs to be divided
- * into. */
- u64 num_chunks = (original_size + WIM_CHUNK_SIZE - 1) / WIM_CHUNK_SIZE;
-
- u64 num_chunk_entries = num_chunks - 1;
-
- /* Size of the chunk entries--- 8 bytes for files over 4GB, otherwise 4
- * bytes */
- uint chunk_entry_size = (original_size >= (u64)1 << 32) ? 8 : 4;
-
- /* Array in which to construct the chunk offset table. */
- u64 chunk_offsets[num_chunk_entries];
-
- /* Offset of the start of the chunk table in the output file. */
- off_t chunk_tab_offset = ftello(out);
-
- /* Total size of the chunk table (as written to the file) */
- u64 chunk_tab_size = chunk_entry_size * num_chunk_entries;
-
- /* Reserve space for the chunk table. */
- if (fwrite(chunk_offsets, 1, chunk_tab_size, out) != chunk_tab_size) {
- ERROR("Failed to write chunk offset table: %m\n");
- return WIMLIB_ERR_WRITE;
- }
-
- /* Read each chunk of the file, compress it, write it to the output
- * file, and update th chunk offset table. */
- u64 cur_chunk_offset = 0;
- for (u64 i = 0; i < num_chunks; i++) {
-
- u64 uncompressed_offset = i * WIM_CHUNK_SIZE;
- u64 uncompressed_chunk_size = min(WIM_CHUNK_SIZE,
- original_size - uncompressed_offset);
-
- const u8 *uncompressed_p;
- if (uncompressed_resource != NULL) {
- uncompressed_p = uncompressed_resource +
- uncompressed_offset;
-
- } else {
- /* Read chunk i of the file into uncompressed_buf. */
- ret = read_resource(in, size, original_size, offset, input_ctype,
- uncompressed_chunk_size,
- uncompressed_offset,
- uncompressed_buf);
- if (ret != 0)
- return ret;
- uncompressed_p = uncompressed_buf;
- }
-
- if (i != 0)
- chunk_offsets[i - 1] = cur_chunk_offset;
-
- uint compressed_len;
-
- ret = compress(uncompressed_p, uncompressed_chunk_size,
- compressed_buf, &compressed_len);
-
- /* if compress() returned nonzero, the compressed chunk would
- * have been at least as large as the uncompressed chunk. In
- * this situation, the WIM format requires that the uncompressed
- * chunk be written instead. */
- const u8 *buf_to_write;
- uint len_to_write;
- if (ret == 0) {
- buf_to_write = compressed_buf;
- len_to_write = compressed_len;
- } else {
- buf_to_write = uncompressed_p;
- len_to_write = uncompressed_chunk_size;
- }
-
- if (fwrite(buf_to_write, 1, len_to_write, out) != len_to_write) {
- ERROR("Failed to write compressed file resource: %m\n");
- return WIMLIB_ERR_WRITE;
- }
- cur_chunk_offset += len_to_write;
- }
-
- /* The chunk offset after the last chunk, plus the size of the chunk
- * table, gives the total compressed size of the resource. */
- *new_size_ret = cur_chunk_offset + chunk_tab_size;
-
- /* Now that all entries of the chunk table are determined, rewind the
- * stream to where the chunk table was, and write it back out. */
-
- if (fseeko(out, chunk_tab_offset, SEEK_SET) != 0) {
- ERROR("Failed to seek to beginning of chunk table: %m\n");
- return WIMLIB_ERR_READ;
- }
-
- if (chunk_entry_size == 8) {
- array_to_le64(chunk_offsets, num_chunk_entries);
-
- if (fwrite(chunk_offsets, 1, chunk_tab_size, out) !=
- chunk_tab_size) {
- ERROR("Failed to write chunk table: %m\n");
- return WIMLIB_ERR_WRITE;
- }
- } else {
- u32 chunk_entries_small[num_chunk_entries];
- for (u64 i = 0; i < num_chunk_entries; i++)
- chunk_entries_small[i] = to_le32(chunk_offsets[i]);
- if (fwrite(chunk_entries_small, 1, chunk_tab_size, out) !=
- chunk_tab_size) {
- ERROR("Failed to write chunk table: %m\n");
- return WIMLIB_ERR_WRITE;
- }
- }
-
- if (fseeko(out, 0, SEEK_END) != 0) {
- ERROR("Failed to seek to end of output file: %m\n");
- return WIMLIB_ERR_WRITE;
- }
-
- return 0;
-}
-
-int write_resource_from_memory(const u8 resource[], int out_ctype,
- u64 resource_original_size, FILE *out,
- u64 *resource_size_ret)
-{
- if (out_ctype == WIM_COMPRESSION_TYPE_NONE) {
- if (fwrite(resource, 1, resource_original_size, out) !=
- resource_original_size) {
- ERROR("Failed to write resource of length "
- "%"PRIu64": %m\n",
- resource_original_size);
- return WIMLIB_ERR_WRITE;
- }
- *resource_size_ret = resource_original_size;
- return 0;
- } else {
- return recompress_resource(NULL, resource, resource_original_size,
- resource_original_size, 0, 0, out, out_ctype,
- resource_size_ret);
- }
-}
-
-
-/*
- * Transfers a file resource from a FILE* opened for reading to a FILE* opened
- * for writing, possibly changing the compression type.
- *
- * @in: The FILE* that contains the file resource.
- * @size: The (compressed) size of the file resource.
- * @original_size: The uncompressed size of the file resource.
- * @offset: The offset of the file resource in the input file.
- * @input_ctype: The compression type of the file resource in the input
- * file.
- * @out: The FILE* for the output file. The file resource is
- * written at the current position of @out.
- * @output_ctype: The compression type to which the file resource will be
- * converted.
- * @output_res_entry: A pointer to a resource entry that, upon successful
- * return of this function, will have the size,
- * original size, offset, and flags fields filled
- * in for the file resource written to the output
- * file.
- */
-static int transfer_file_resource(FILE *in, u64 size, u64 original_size,
- off_t offset, int input_ctype, FILE *out,
- int output_ctype,
- struct resource_entry *output_res_entry)
-{
- int ret;
-
- /* Handle zero-length files */
- if (original_size == 0) {
- memset(output_res_entry, 0, sizeof(*output_res_entry));
- return 0;
- }
-
- /* Get current offset in the output file. */
- output_res_entry->offset = ftello(out);
- if (output_res_entry->offset == -1) {
- ERROR("Failed to get output position: %m\n");
- return WIMLIB_ERR_WRITE;
- }
-
- if (output_ctype == input_ctype) {
- /* The same compression types; simply copy the resource. */
-
- ret = copy_between_files(in, offset, out, size);
- if (ret != 0)
- return ret;
- output_res_entry->size = size;
- } else {
- /* Different compression types. */
-
- if (output_ctype == WIM_COMPRESSION_TYPE_NONE) {
- /* Uncompress a compressed file resource */
- ret = uncompress_resource(in, size,
- original_size, offset,
- input_ctype, out);
- if (ret != 0)
- return ret;
- output_res_entry->size = original_size;
- } else {
- u64 new_size;
- /* Compress an uncompressed file resource, or compress a
- * compressed file resource using a different
- * compression type (the latter is currently unsupported
- * since only LZX compression is supported. */
- ret = recompress_resource(in, NULL, size, original_size,
- offset, input_ctype, out,
- output_ctype, &new_size);
- if (ret != 0)
- return ret;
- output_res_entry->size = new_size;
- }
-
- }
-
- output_res_entry->original_size = original_size;
- if (output_ctype == WIM_COMPRESSION_TYPE_NONE)
- output_res_entry->flags = 0;
- else
- output_res_entry->flags = WIM_RESHDR_FLAG_COMPRESSED;
- return 0;
-}
-
-/*
- * Writes a file resource to the output file.
- *
- * @dentry: The dentry for the file resource.
- * @wim_p: A pointer to the WIMStruct. The fields of interest to this
- * function are the input and output file streams and the lookup table.
- * @return zero on success, nonzero on failure.
- */
-static int write_file_resource(struct dentry *dentry, void *wim_p)
-{
- WIMStruct *w;
- FILE *out;
- FILE *in;
- struct lookup_table_entry *lte;
- int in_wim_ctype;
- int out_wim_ctype;
- int input_res_ctype;
- struct resource_entry *input_res_entry;
- struct resource_entry *output_res_entry;
- u64 len;
- int ret;
-
- w = wim_p;
- out = w->out_fp;
-
- /* Directories don't need file resources. */
- if (dentry_is_directory(dentry))
- return 0;
-
- /* Get the lookup entry for the file resource. */
- lte = wim_lookup_resource(w, dentry);
- if (!lte)
- return 0;
-
- /* No need to write file resources twice. (This indicates file
- * resources that are part of a hard link set.) */
- if (++lte->out_refcnt != 1)
- return 0;
-
- out_wim_ctype = wimlib_get_compression_type(w);
- output_res_entry = <e->output_resource_entry;
-
- /* Figure out if we can read the resource from the WIM file, or
- * if we have to read it from the filesystem outside. */
- if (lte->file_on_disk) {
-
- /* Read from disk (uncompressed) */
-
- len = lte->resource_entry.original_size;
-
- in = fopen(lte->file_on_disk, "rb");
- if (!in) {
- ERROR("Failed to open the file `%s': %m\n",
- lte->file_on_disk);
- return WIMLIB_ERR_OPEN;
- }
-
- if (w->verbose)
- puts(lte->file_on_disk);
-
- ret = transfer_file_resource(in, len, len, 0,
- WIM_COMPRESSION_TYPE_NONE, out,
- out_wim_ctype, output_res_entry);
- fclose(in);
- } else {
-
- /* Read from input WIM (possibly compressed) */
-
- /* It may be a different WIM file, in the case of
- * exporting images from one WIM file to another */
- if (lte->other_wim_fp) {
- /* Different WIM file. */
- in = lte->other_wim_fp;
- in_wim_ctype = lte->other_wim_ctype;
- } else {
- /* Same WIM file. */
- in = w->fp;
- in_wim_ctype = out_wim_ctype;
- }
- input_res_entry = <e->resource_entry;
- input_res_ctype = resource_compression_type(
- in_wim_ctype,
- input_res_entry->flags);
-
- ret = transfer_file_resource(in,
- input_res_entry->size,
- input_res_entry->original_size,
- input_res_entry->offset,
- input_res_ctype,
- out,
- out_wim_ctype,
- output_res_entry);
- }
- return ret;
-}
-
git://wimlib.net / wimlib / commitdiff