header.c, lookup_table.c: Read/write data from structures
authorEric Biggers <ebiggers3@gmail.com>
Fri, 17 May 2013 18:01:51 +0000 (13:01 -0500)
committerEric Biggers <ebiggers3@gmail.com>
Fri, 17 May 2013 18:01:51 +0000 (13:01 -0500)
include/wimlib/header.h
include/wimlib/resource.h
include/wimlib/sha1.h
src/header.c
src/lookup_table.c
src/metadata_resource.c
src/resource.c
src/split.c

index 151d6c7..b250381 100644 (file)
@@ -4,12 +4,10 @@
 #include "wimlib/resource.h"
 #include "wimlib/types.h"
 
-#define WIM_MAGIC_LEN  8
 #define WIM_GID_LEN    16
-#define WIM_UNUSED_LEN 60
 
 /* Length of the WIM header on disk. */
-#define WIM_HEADER_DISK_SIZE (148 + WIM_UNUSED_LEN)
+#define WIM_HEADER_DISK_SIZE 208
 
 /* Compressed resources in the WIM are divided into separated compressed chunks
  * of this size. */
  * yet.  The differences between the versions are undocumented. */
 #define WIM_VERSION 0x10d00
 
-/* Header at the very beginning of the WIM file. */
+/* Header at the very beginning of the WIM file.  This is the in-memory
+ * representation and does not include all fields; see `struct wim_header_disk'
+ * for the on-disk structure. */
 struct wim_header {
-       /* Identifies the file as WIM file. Must be exactly
-        * {'M', 'S', 'W', 'I', 'M', 0, 0, 0}  */
-       //u8  magic[WIM_MAGIC_LEN];
-
-       /* size of WIM header in bytes. */
-       //u32 hdr_size;
-
-       /* Version of the WIM file.  Microsoft provides no documentation about
-        * exactly what this field affects about the file format, other than the
-        * fact that more recent versions have a higher value. */
-       //u32 version;
-
        /* Bitwise OR of one or more of the WIM_HDR_FLAG_* defined below. */
        u32 flags;
 
-       /* The size of the pieces that the uncompressed files were split up into
-        * when they were compressed.  This should be the same as
-        * WIM_CHUNK_SIZE.  Microsoft incorrectly documents this as "the size of
-        * the compressed .wim file in bytes".*/
-       //u32 chunk_size;
-
        /* A unique identifier for the WIM file. */
        u8 guid[WIM_GID_LEN];
 
@@ -72,9 +54,6 @@ struct wim_header {
        /* The location of the optional integrity table used to verify the
         * integrity WIM.  Zeroed out if there is no integrity table.*/
        struct resource_entry integrity;
-
-       /* Reserved for future disuse */
-       //u8 unused[WIM_UNUSED_LEN];
 };
 
 /* Flags for the `flags' field of the struct wim_header: */
index 757531c..c759861 100644 (file)
@@ -23,6 +23,12 @@ struct resource_entry {
        u64 original_size;
 };
 
+struct resource_entry_disk {
+       u8 size[7];
+       u8 flags;
+       le64 offset;
+       le64 original_size;
+} _packed_attribute;
 
 /* Flags for the `flags' field of the struct resource_entry structure. */
 
@@ -84,11 +90,13 @@ read_resource_prefix(const struct wim_lookup_table_entry *lte,
                     u64 size, consume_data_callback_t cb, void *ctx_or_buf,
                     int flags);
 
-extern const void *
-get_resource_entry(const void *p, struct resource_entry *entry);
+extern void
+get_resource_entry(const struct resource_entry_disk *disk_entry,
+                  struct resource_entry *entry);
 
-extern void *
-put_resource_entry(void *p, const struct resource_entry *entry);
+extern void
+put_resource_entry(const struct resource_entry *entry,
+                  struct resource_entry_disk *disk_entry);
 
 extern int
 read_partial_wim_resource_into_buf(const struct wim_lookup_table_entry *lte,
index 1f7c50f..76e6d5e 100644 (file)
@@ -22,17 +22,16 @@ random_hash(u8 hash[SHA1_HASH_SIZE])
        randomize_byte_array(hash, SHA1_HASH_SIZE);
 }
 
-static inline bool
-hashes_equal(const u8 h1[SHA1_HASH_SIZE], const u8 h2[SHA1_HASH_SIZE])
+static inline int
+hashes_cmp(const u8 h1[SHA1_HASH_SIZE], const u8 h2[SHA1_HASH_SIZE])
 {
-       return memcmp(h1, h2, SHA1_HASH_SIZE) == 0;
+       return memcmp(h1, h2, SHA1_HASH_SIZE);
 }
 
-static inline int
-hashes_cmp(const u8 h1[SHA1_HASH_SIZE],
-                            const u8 h2[SHA1_HASH_SIZE])
+static inline bool
+hashes_equal(const u8 h1[SHA1_HASH_SIZE], const u8 h2[SHA1_HASH_SIZE])
 {
-       return memcmp(h1, h2, SHA1_HASH_SIZE);
+       return !hashes_cmp(h1, h2);
 }
 
 static inline void
@@ -42,22 +41,19 @@ print_hash(const u8 hash[SHA1_HASH_SIZE], FILE *out)
 }
 
 static inline bool
-is_zero_hash(const u8 hash[SHA1_HASH_SIZE])
+is_zero_hash(const u8 *hash)
 {
-       if (hash)
-               for (u8 i = 0; i < SHA1_HASH_SIZE / 4; i++)
-                       if (((const u32*)hash)[i])
-                               return false;
-       return true;
+       if (!hash)
+               return true;
+       return hashes_equal(hash, zero_hash);
 }
 
 static inline void
 zero_out_hash(u8 hash[SHA1_HASH_SIZE])
 {
-       memset(hash, 0, SHA1_HASH_SIZE);
+       copy_hash(hash, zero_hash);
 }
 
-
 #ifdef WITH_LIBCRYPTO
 
 #include <openssl/sha.h>
index c0518ec..0066d75 100644 (file)
@@ -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"
 #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 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;
+
+       /* 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;
 
-/* First 8 bytes in every WIM file. */
-static const u8 wim_magic_chars[WIM_MAGIC_LEN] = {
-                       'M', 'S', 'W', 'I', 'M', '\0', '\0', '\0' };
+       /* 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)
 {
-       size_t bytes_read;
-       u8 buf[WIM_HEADER_DISK_SIZE];
-       const void *p;
+       struct wim_header_disk disk_hdr _aligned_attribute(8);
 
-       u32 hdr_size;
-       u32 wim_version;
-       u32 chunk_size;
-
-       DEBUG("Reading WIM header from \"%"TS"\".", filename);
+       DEBUG("Reading WIM header from \"%"TS"\"", filename);
 
-       bytes_read = full_pread(in_fd, buf, WIM_HEADER_DISK_SIZE, 0);
-
-       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);
+       BUILD_BUG_ON(sizeof(struct wim_header_disk) != 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",
@@ -111,15 +169,14 @@ 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)
+       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);
@@ -130,26 +187,11 @@ read_header(const tchar *filename, int in_fd,
                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;
 }
 
@@ -164,34 +206,28 @@ read_header(const tchar *filename, int in_fd,
 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;
        }
index 2e45f8f..9570886 100644 (file)
@@ -28,7 +28,7 @@
 #  include "config.h"
 #endif
 
-#include "wimlib/buffer_io.h"
+#include "wimlib/endianness.h"
 #include "wimlib/error.h"
 #include "wimlib/file_io.h"
 #include "wimlib/lookup_table.h"
@@ -348,9 +348,22 @@ for_lookup_table_entry_pos_sorted(struct wim_lookup_table *table,
        return ret;
 }
 
+/* On-disk format of a WIM lookup table entry (stream entry). */
+struct wim_lookup_table_entry_disk {
+       /* Location, offset, compression status, and metadata status of the
+        * stream. */
+       struct resource_entry_disk resource_entry;
 
-/* Size of each lookup table entry in the WIM file. */
-#define WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE 50
+       /* Which part of the split WIM this stream is in; indexed from 1. */
+       u16 part_number;
+
+       /* Reference count of this stream over all WIM images. */
+       u32 refcnt;
+
+       /* SHA1 message digest of the uncompressed data of this stream, or
+        * optionally all zeroes if this stream is of zero length. */
+       u8 hash[SHA1_HASH_SIZE];
+} _packed_attribute;
 
 /*
  * Reads the lookup table from a WIM file.
@@ -366,11 +379,12 @@ read_lookup_table(WIMStruct *w)
        size_t num_entries;
        struct wim_lookup_table *table;
        struct wim_lookup_table_entry *cur_entry, *duplicate_entry;
-       u8 table_buf[(BUFFER_SIZE / WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE) *
-                       WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE];
-       const u8 *p;
+       struct wim_lookup_table_entry_disk
+                       table_buf[BUFFER_SIZE / sizeof(struct wim_lookup_table_entry_disk)]
+                               _aligned_attribute(8);
        off_t offset;
        size_t buf_entries_remaining;
+       const struct wim_lookup_table_entry_disk *disk_entry;
 
        DEBUG("Reading lookup table: offset %"PRIu64", size %"PRIu64"",
              w->hdr.lookup_table_res_entry.offset,
@@ -383,7 +397,7 @@ read_lookup_table(WIMStruct *w)
        }
 
        num_entries = w->hdr.lookup_table_res_entry.size /
-                     WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE;
+                     sizeof(struct wim_lookup_table_entry_disk);
        table = new_lookup_table(num_entries * 2 + 1);
        if (!table)
                return WIMLIB_ERR_NOMEM;
@@ -391,15 +405,14 @@ read_lookup_table(WIMStruct *w)
        w->current_image = 0;
        offset = w->hdr.lookup_table_res_entry.offset;
        buf_entries_remaining = 0;
-       for (; num_entries != 0; num_entries--, buf_entries_remaining--) {
+       for (; num_entries != 0;
+            num_entries--, buf_entries_remaining--, disk_entry++)
+       {
                if (buf_entries_remaining == 0) {
                        size_t entries_to_read, bytes_to_read;
 
-                       entries_to_read = min(sizeof(table_buf) /
-                                               WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE,
-                                             num_entries);
-                       bytes_to_read = entries_to_read *
-                                               WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE;
+                       entries_to_read = min(ARRAY_LEN(table_buf), num_entries);
+                       bytes_to_read = entries_to_read * sizeof(struct wim_lookup_table_entry_disk);
                        if (full_pread(w->in_fd, table_buf,
                                       bytes_to_read, offset) != bytes_to_read)
                        {
@@ -409,7 +422,7 @@ read_lookup_table(WIMStruct *w)
                                goto out_free_lookup_table;
                        }
                        offset += bytes_to_read;
-                       p = table_buf;
+                       disk_entry = table_buf;
                        buf_entries_remaining = entries_to_read;
                }
                cur_entry = new_lookup_table_entry();
@@ -420,10 +433,10 @@ read_lookup_table(WIMStruct *w)
 
                cur_entry->wim = w;
                cur_entry->resource_location = RESOURCE_IN_WIM;
-               p = get_resource_entry(p, &cur_entry->resource_entry);
-               p = get_u16(p, &cur_entry->part_number);
-               p = get_u32(p, &cur_entry->refcnt);
-               p = get_bytes(p, SHA1_HASH_SIZE, cur_entry->hash);
+               get_resource_entry(&disk_entry->resource_entry, &cur_entry->resource_entry);
+               cur_entry->part_number = le16_to_cpu(disk_entry->part_number);
+               cur_entry->refcnt = le32_to_cpu(disk_entry->refcnt);
+               copy_hash(cur_entry->hash, disk_entry->hash);
 
                if (cur_entry->part_number != w->hdr.part_number) {
                        ERROR("A lookup table entry in part %hu of the WIM "
@@ -534,14 +547,14 @@ out:
 }
 
 
-static u8 *
-write_lookup_table_entry(const struct wim_lookup_table_entry *lte, u8 *buf_p)
+static void
+write_lookup_table_entry(const struct wim_lookup_table_entry *lte,
+                        struct wim_lookup_table_entry_disk *disk_entry)
 {
-       buf_p = put_resource_entry(buf_p, &lte->output_resource_entry);
-       buf_p = put_u16(buf_p, lte->part_number);
-       buf_p = put_u32(buf_p, lte->out_refcnt);
-       buf_p = put_bytes(buf_p, SHA1_HASH_SIZE, lte->hash);
-       return buf_p;
+       put_resource_entry(&lte->output_resource_entry, &disk_entry->resource_entry);
+       disk_entry->part_number = cpu_to_le16(lte->part_number);
+       disk_entry->refcnt = cpu_to_le32(lte->out_refcnt);
+       copy_hash(disk_entry->hash, lte->hash);
 }
 
 int
@@ -551,32 +564,34 @@ write_lookup_table_from_stream_list(struct list_head *stream_list,
 {
        int ret;
        off_t start_offset;
-       u8 table_buf[(BUFFER_SIZE / WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE) *
-                       WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE];
-       u8 *buf_p;
+       struct wim_lookup_table_entry_disk
+                       table_buf[BUFFER_SIZE / sizeof(struct wim_lookup_table_entry_disk)]
+                               _aligned_attribute(8);
        size_t table_size;
        size_t bytes_to_write;
        struct wim_lookup_table_entry *lte;
+       size_t cur_idx;
 
        start_offset = filedes_offset(out_fd);
        if (start_offset == -1)
                goto write_error;
 
-       buf_p = table_buf;
        table_size = 0;
+       cur_idx = 0;
        list_for_each_entry(lte, stream_list, lookup_table_list) {
-               if (buf_p == table_buf + sizeof(table_buf)) {
+               if (cur_idx == ARRAY_LEN(table_buf)) {
                        bytes_to_write = sizeof(table_buf);
                        if (full_write(out_fd, table_buf,
                                       bytes_to_write) != bytes_to_write)
                                goto write_error;
                        table_size += bytes_to_write;
-                       buf_p = table_buf;
+                       cur_idx = 0;
                }
-               buf_p = write_lookup_table_entry(lte, buf_p);
+               write_lookup_table_entry(lte, &table_buf[cur_idx]);
+               cur_idx++;
        }
-       bytes_to_write = buf_p - table_buf;
-       if (bytes_to_write != 0) {
+       if (cur_idx != 0) {
+               bytes_to_write = cur_idx * sizeof(struct wim_lookup_table_entry_disk);
                if (full_write(out_fd, table_buf,
                               bytes_to_write) != bytes_to_write)
                        goto write_error;
index 5b22ab6..13ebf51 100644 (file)
@@ -59,7 +59,6 @@ read_metadata_resource(WIMStruct *wim, struct wim_image_metadata *imd)
        struct wim_dentry *root;
        const struct wim_lookup_table_entry *metadata_lte;
        u64 metadata_len;
-       struct wim_security_data *security_data;
 
        metadata_lte = imd->metadata_lte;
        metadata_len = wim_resource_size(metadata_lte);
@@ -114,7 +113,7 @@ read_metadata_resource(WIMStruct *wim, struct wim_image_metadata *imd)
         * and calculate the offset in the metadata resource of the root dentry.
         * */
 
-       ret = read_wim_security_data(buf, metadata_len, &security_data);
+       ret = read_wim_security_data(buf, metadata_len, &imd->security_data);
        if (ret)
                goto out_free_buf;
 
@@ -128,7 +127,7 @@ read_metadata_resource(WIMStruct *wim, struct wim_image_metadata *imd)
        }
 
        ret = read_dentry(buf, metadata_len,
-                         security_data->total_length, root);
+                         imd->security_data->total_length, root);
 
        if (ret == 0 && root->length == 0) {
                ERROR("Metadata resource cannot begin with end-of-directory entry!");
@@ -157,6 +156,8 @@ read_metadata_resource(WIMStruct *wim, struct wim_image_metadata *imd)
                goto out_free_dentry_tree;
 
        if (!wim->all_images_verified) {
+               /* Note: verify_dentry() expects to access imd->security_data,
+                * so it needs to be set before here. */
                DEBUG("Running miscellaneous verifications on the dentry tree");
                for_lookup_table_entry(wim->lookup_table, lte_zero_real_refcnt, NULL);
                ret = for_dentry_in_tree(root, verify_dentry, wim);
@@ -167,13 +168,13 @@ read_metadata_resource(WIMStruct *wim, struct wim_image_metadata *imd)
        DEBUG("Done reading image metadata");
 
        imd->root_dentry = root;
-       imd->security_data = security_data;
        INIT_LIST_HEAD(&imd->unhashed_streams);
        goto out_free_buf;
 out_free_dentry_tree:
        free_dentry_tree(root, wim->lookup_table);
 out_free_security_data:
-       free_wim_security_data(security_data);
+       free_wim_security_data(imd->security_data);
+       imd->security_data = NULL;
 out_free_buf:
        FREE(buf);
        return ret;
index 9192062..38f005f 100644 (file)
@@ -27,8 +27,8 @@
 #endif
 
 #include "wimlib.h"
-#include "wimlib/buffer_io.h"
 #include "wimlib/dentry.h"
+#include "wimlib/endianness.h"
 #include "wimlib/error.h"
 #include "wimlib/file_io.h"
 #include "wimlib/lookup_table.h"
@@ -356,48 +356,63 @@ read_error:
        goto out;
 }
 
-/* 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)
+/* 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)
 {
-       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
index 05a7bee..78dc8ab 100644 (file)
@@ -28,7 +28,7 @@
 #endif
 
 #include "wimlib.h"
-#include "wimlib/buffer_io.h"
+#include "wimlib/endianness.h"
 #include "wimlib/error.h"
 #include "wimlib/file_io.h"
 #include "wimlib/lookup_table.h"
@@ -224,7 +224,7 @@ wimlib_split(WIMStruct *w, const tchar *swm_name,
        for (int i = 1; i <= total_parts; i++) {
                const tchar *part_name;
                int part_fd;
-               u8 part_data_buf[4];
+               le16 part_data[2];
                size_t bytes_written;
 
                if (i == 1) {
@@ -241,13 +241,13 @@ wimlib_split(WIMStruct *w, const tchar *swm_name,
                        ret = WIMLIB_ERR_OPEN;
                        goto out;
                }
-               put_u16(&part_data_buf[0], i);
-               put_u16(&part_data_buf[2], total_parts);
+               part_data[0] = cpu_to_le16(i);
+               part_data[1] = cpu_to_le16(total_parts);
 
-               bytes_written = full_pwrite(part_fd, part_data_buf,
-                                           sizeof(part_data_buf), 40);
+               bytes_written = full_pwrite(part_fd, part_data,
+                                           sizeof(part_data), 40);
                ret = close(part_fd);
-               if (bytes_written != sizeof(part_data_buf) || ret != 0) {
+               if (bytes_written != sizeof(part_data) || ret != 0) {
                        ERROR_WITH_ERRNO("Error updating header of `%"TS"'",
                                         part_name);
                        ret = WIMLIB_ERR_WRITE;