X-Git-Url: https://wimlib.net/git/?p=wimlib;a=blobdiff_plain;f=src%2Fresource.c;h=84d4441bb26add7738f25cee44b3af044e97e145;hp=464ca711ea43a3dbb7dda4d87b3a4d9a8e0b20ec;hb=c9482ee98e12fa3f1073e4fc3c56f5eef3c40f32;hpb=f9695b9f40035f1a20968293255761a8301eaba0 diff --git a/src/resource.c b/src/resource.c index 464ca711..84d4441b 100644 --- a/src/resource.c +++ b/src/resource.c @@ -22,25 +22,37 @@ * wimlib; if not, see http://www.gnu.org/licenses/. */ -#include "wimlib_internal.h" -#include "dentry.h" -#include "lookup_table.h" -#include "buffer_io.h" -#include "sha1.h" +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include "wimlib.h" +#include "wimlib/dentry.h" +#include "wimlib/endianness.h" +#include "wimlib/error.h" +#include "wimlib/file_io.h" +#include "wimlib/lookup_table.h" +#include "wimlib/resource.h" +#include "wimlib/sha1.h" #ifdef __WIN32__ -# include "win32.h" +/* for read_win32_file_prefix(), read_win32_encrypted_file_prefix() */ +# include "wimlib/win32.h" #endif -#include -#include -#include -#include -#include +#ifdef WITH_NTFS_3G +/* for read_ntfs_file_prefix() */ +# include "wimlib/ntfs_3g.h" +#endif #ifdef HAVE_ALLOCA_H # include #endif +#include +#include +#include +#include +#include /* * Reads all or part of a compressed WIM resource. @@ -48,7 +60,7 @@ * Returns zero on success, nonzero on failure. */ static int -read_compressed_resource(filedes_t in_fd, +read_compressed_resource(int in_fd, u64 resource_compressed_size, u64 resource_uncompressed_size, u64 resource_offset, @@ -85,8 +97,8 @@ read_compressed_resource(filedes_t in_fd, /* Calculate how many chunks the resource consists of in its entirety. * */ - u64 num_chunks = (resource_uncompressed_size + WIM_CHUNK_SIZE - 1) / - WIM_CHUNK_SIZE; + u64 num_chunks = DIV_ROUND_UP(resource_uncompressed_size, WIM_CHUNK_SIZE); + /* As mentioned, the first chunk has no entry in the chunk table. */ u64 num_chunk_entries = num_chunks - 1; @@ -111,11 +123,20 @@ read_compressed_resource(filedes_t in_fd, if (end_chunk != num_chunks - 1) num_needed_chunks++; + /* According to M$'s documentation, if the uncompressed size of + * the file is greater than 4 GB, the chunk entries are 8-byte + * integers. Otherwise, they are 4-byte integers. */ + u64 chunk_entry_size = (resource_uncompressed_size > + (u64)1 << 32) ? 8 : 4; + + /* Size of the full chunk table in the WIM file. */ + u64 chunk_table_size = chunk_entry_size * num_chunk_entries; + /* Allocate the chunk table. It will only contain offsets for the * chunks that are actually needed for this read. */ u64 *chunk_offsets; bool chunk_offsets_malloced; - if (num_needed_chunks < 1000) { + if (num_needed_chunks < 1024) { chunk_offsets = alloca(num_needed_chunks * sizeof(u64)); chunk_offsets_malloced = false; } else { @@ -139,14 +160,6 @@ read_compressed_resource(filedes_t in_fd, if (start_chunk == 0) chunk_offsets[0] = 0; - /* According to M$'s documentation, if the uncompressed size of - * the file is greater than 4 GB, the chunk entries are 8-byte - * integers. Otherwise, they are 4-byte integers. */ - u64 chunk_entry_size = (resource_uncompressed_size >= (u64)1 << 32) ? - 8 : 4; - - /* Size of the full chunk table in the WIM file. */ - u64 chunk_table_size = chunk_entry_size * num_chunk_entries; /* Read the needed chunk offsets from the table in the WIM file. */ @@ -163,12 +176,30 @@ read_compressed_resource(filedes_t in_fd, u64 file_offset_of_needed_chunk_entries = resource_offset + start_table_idx * chunk_entry_size; + /* Allocate a buffer into which to read the raw chunk entries. */ + void *chunk_tab_buf; + bool chunk_tab_buf_malloced = false; + /* Number of bytes we need to read from the chunk table. */ size_t size = num_needed_chunk_entries * chunk_entry_size; + if ((u64)size != num_needed_chunk_entries * chunk_entry_size) { + ERROR("Compressed read request too large to fit into memory!"); + ret = WIMLIB_ERR_NOMEM; + goto out; + } - /* Read the raw data into the end of the chunk_offsets array to - * avoid allocating another array. */ - void *chunk_tab_buf = (void*)&chunk_offsets[num_needed_chunks] - size; + if (size < 4096) { + chunk_tab_buf = alloca(size); + } else { + chunk_tab_buf = malloc(size); + if (!chunk_tab_buf) { + ERROR("Failed to allocate chunk table buffer of " + "size %zu bytes", size); + ret = WIMLIB_ERR_NOMEM; + goto out; + } + chunk_tab_buf_malloced = true; + } if (full_pread(in_fd, chunk_tab_buf, size, file_offset_of_needed_chunk_entries) != size) @@ -182,17 +213,17 @@ read_compressed_resource(filedes_t in_fd, chunk_tab_p++; if (chunk_entry_size == 4) { - u32 *entries = (u32*)chunk_tab_buf; + le32 *entries = (le32*)chunk_tab_buf; while (num_needed_chunk_entries--) *chunk_tab_p++ = le32_to_cpu(*entries++); } else { - u64 *entries = (u64*)chunk_tab_buf; + le64 *entries = (le64*)chunk_tab_buf; while (num_needed_chunk_entries--) *chunk_tab_p++ = le64_to_cpu(*entries++); } - /* Done with the chunk table now. We must now seek to the first chunk - * that is needed for the read. */ + /* Done reading the chunk table now. Now calculate the file offset for + * the first byte of compressed data we need to read. */ u64 cur_read_offset = resource_offset + chunk_table_size + chunk_offsets[0]; @@ -336,6 +367,8 @@ read_compressed_resource(filedes_t in_fd, out: if (chunk_offsets_malloced) FREE(chunk_offsets); + if (chunk_tab_buf_malloced) + FREE(chunk_tab_buf); return ret; read_error: @@ -344,73 +377,63 @@ read_error: goto out; } -/* - * Reads uncompressed data from an open file stream. - */ -int -read_uncompressed_resource(FILE *fp, u64 offset, u64 len, void *contents_ret) +/* Translates a WIM resource entry from the on-disk format to an in-memory + * format. */ +void +get_resource_entry(const struct resource_entry_disk *disk_entry, + struct resource_entry *entry) { - if (fseeko(fp, offset, SEEK_SET) != 0) { - ERROR("Failed to seek to byte %"PRIu64" of input file " - "to read uncompressed resource (len = %"PRIu64")", - offset, len); - return WIMLIB_ERR_READ; - } - if (fread(contents_ret, 1, len, fp) != len) { - if (feof(fp)) { - ERROR("Unexpected EOF in uncompressed file resource"); - } else { - ERROR("Failed to read %"PRIu64" bytes from " - "uncompressed resource at offset %"PRIu64, - len, offset); - } - return WIMLIB_ERR_READ; - } - return 0; -} - -/* Reads the contents of a struct resource_entry, as represented in the on-disk - * format, from the memory pointed to by @p, and fills in the fields of @entry. - * A pointer to the byte after the memory read at @p is returned. */ -const void * -get_resource_entry(const void *p, struct resource_entry *entry) -{ - u64 size; - u8 flags; - - p = get_u56(p, &size); - p = get_u8(p, &flags); - entry->size = size; - entry->flags = flags; + /* Note: disk_entry may not be 8 byte aligned--- in that case, the + * offset and original_size members will be unaligned. (This should be + * okay since `struct resource_entry_disk' is declared as packed.) */ + + /* Read the size and flags into a bitfield portably... */ + entry->size = (((u64)disk_entry->size[0] << 0) | + ((u64)disk_entry->size[1] << 8) | + ((u64)disk_entry->size[2] << 16) | + ((u64)disk_entry->size[3] << 24) | + ((u64)disk_entry->size[4] << 32) | + ((u64)disk_entry->size[5] << 40) | + ((u64)disk_entry->size[6] << 48)); + entry->flags = disk_entry->flags; + entry->offset = le64_to_cpu(disk_entry->offset); + entry->original_size = le64_to_cpu(disk_entry->original_size); /* offset and original_size are truncated to 62 bits to avoid possible * overflows, when converting to a signed 64-bit integer (off_t) or when * adding size or original_size. This is okay since no one would ever * actually have a WIM bigger than 4611686018427387903 bytes... */ - p = get_u64(p, &entry->offset); if (entry->offset & 0xc000000000000000ULL) { WARNING("Truncating offset in resource entry"); entry->offset &= 0x3fffffffffffffffULL; } - p = get_u64(p, &entry->original_size); if (entry->original_size & 0xc000000000000000ULL) { WARNING("Truncating original_size in resource entry"); entry->original_size &= 0x3fffffffffffffffULL; } - return p; } -/* Copies the struct resource_entry @entry to the memory pointed to by @p in the - * on-disk format. A pointer to the byte after the memory written at @p is - * returned. */ -void * -put_resource_entry(void *p, const struct resource_entry *entry) +/* Translates a WIM resource entry from an in-memory format into the on-disk + * format. */ +void +put_resource_entry(const struct resource_entry *entry, + struct resource_entry_disk *disk_entry) { - p = put_u56(p, entry->size); - p = put_u8(p, entry->flags); - p = put_u64(p, entry->offset); - p = put_u64(p, entry->original_size); - return p; + /* Note: disk_entry may not be 8 byte aligned--- in that case, the + * offset and original_size members will be unaligned. (This should be + * okay since `struct resource_entry_disk' is declared as packed.) */ + u64 size = entry->size; + + disk_entry->size[0] = size >> 0; + disk_entry->size[1] = size >> 8; + disk_entry->size[2] = size >> 16; + disk_entry->size[3] = size >> 24; + disk_entry->size[4] = size >> 32; + disk_entry->size[5] = size >> 40; + disk_entry->size[6] = size >> 48; + disk_entry->flags = entry->flags; + disk_entry->offset = cpu_to_le64(entry->offset); + disk_entry->original_size = cpu_to_le64(entry->original_size); } static int @@ -422,7 +445,7 @@ read_partial_wim_resource(const struct wim_lookup_table_entry *lte, u64 offset) { WIMStruct *wim; - filedes_t in_fd; + int in_fd; int ret; wimlib_assert(lte->resource_location == RESOURCE_IN_WIM); @@ -437,7 +460,7 @@ read_partial_wim_resource(const struct wim_lookup_table_entry *lte, lte->resource_entry.size, lte->resource_entry.original_size, lte->resource_entry.offset, - wimlib_get_compression_type(wim), + wim->compression_type, size, offset, cb, @@ -588,8 +611,6 @@ typedef int (*read_resource_prefix_handler_t)(const struct wim_lookup_table_entr * size until the resource is exhausted. * * If the resource is located in a WIM file, @flags can be: - * * WIMLIB_RESOURCE_FLAG_THREADSAFE_READ if it must be safe to access the resource - * concurrently by multiple threads. * * WIMLIB_RESOURCE_FLAG_RAW if the raw compressed data is to be supplied * instead of the uncompressed data. * Otherwise, the @flags are ignored. @@ -670,13 +691,13 @@ extract_wim_resource(const struct wim_lookup_table_entry *lte, u8 hash[SHA1_HASH_SIZE]; sha1_final(hash, &ctx.sha_ctx); if (!hashes_equal(hash, lte->hash)) { - #ifdef ENABLE_ERROR_MESSAGES - ERROR("Invalid SHA1 message digest " - "on the following WIM resource:"); - print_lookup_table_entry(lte, stderr); - if (lte->resource_location == RESOURCE_IN_WIM) - ERROR("The WIM file appears to be corrupt!"); - #endif + if (wimlib_print_errors) { + ERROR("Invalid SHA1 message digest " + "on the following WIM resource:"); + print_lookup_table_entry(lte, stderr); + if (lte->resource_location == RESOURCE_IN_WIM) + ERROR("The WIM file appears to be corrupt!"); + } ret = WIMLIB_ERR_INVALID_RESOURCE_HASH; } }