]> wimlib.net Git - wimlib/blobdiff - src/write.c
Update version to 1.3.2
[wimlib] / src / write.c
index 1c574057e1345b7fde0492b935864d653867e843..6a07c44ed3aeae03b20f0ad85e76a7481eff8354 100644 (file)
 #  define INVALID_HANDLE_VALUE ((HANDLE)(-1))
 #endif
 
-#if TCHAR_IS_UTF16LE
-#  include <wchar.h>
-#endif
-
 static int
 fflush_and_ftruncate(FILE *fp, off_t size)
 {
@@ -155,21 +151,29 @@ out:
 }
 
 /*
- * Pointer to function to compresses a chunk of a WIM resource.
+ * compress_func_t- Pointer to a function to compresses a chunk
+ *                  of a WIM resource.  This may be either xpress_compress()
+ *                  (xpress-compress.c) or lzx_compress() (lzx-compress.c).
+ *
+ * @chunk:       Uncompressed data of the chunk.
+ * @chunk_size:          Size of the uncompressed chunk, in bytes.
+ * @out:         Pointer to output buffer of size at least (@chunk_size - 1) bytes.
  *
- * @chunk:             Uncompressed data of the chunk.
- * @chunk_size:                Size of the uncompressed chunk in bytes.
- * @compressed_chunk:  Pointer to output buffer of size at least
- *                             (@chunk_size - 1) bytes.
- * @compressed_chunk_len_ret:  Pointer to an unsigned int into which the size
- *                                     of the compressed chunk will be
- *                                     returned.
+ * Returns the size of the compressed data written to @out in bytes, or 0 if the
+ * data could not be compressed to (@chunk_size - 1) bytes or fewer.
  *
- * Returns zero if compressed succeeded, and nonzero if the chunk could not be
- * compressed to any smaller than @chunk_size.  This function cannot fail for
- * any other reasons.
+ * As a special requirement, the compression code is optimized for the WIM
+ * format and therefore requires (@chunk_size <= 32768).
+ *
+ * As another special requirement, the compression code will read up to 8 bytes
+ * off the end of the @chunk array for performance reasons.  The values of these
+ * bytes will not affect the output of the compression, but the calling code
+ * must make sure that the buffer holding the uncompressed chunk is actually at
+ * least (@chunk_size + 8) bytes, or at least that these extra bytes are in
+ * mapped memory that will not cause a memory access violation if accessed.
  */
-typedef int (*compress_func_t)(const void *, unsigned, void *, unsigned *);
+typedef unsigned (*compress_func_t)(const void *chunk, unsigned chunk_size,
+                                   void *out);
 
 compress_func_t
 get_compress_func(int out_ctype)
@@ -202,19 +206,20 @@ write_wim_resource_chunk(const u8 chunk[], unsigned chunk_size,
        unsigned out_chunk_size;
        if (chunk_tab) {
                u8 *compressed_chunk = alloca(chunk_size);
-               int ret;
 
-               ret = compress(chunk, chunk_size, compressed_chunk,
-                              &out_chunk_size);
-               if (ret == 0) {
+               out_chunk_size = compress(chunk, chunk_size, compressed_chunk);
+               if (out_chunk_size) {
+                       /* Write compressed */
                        out_chunk = compressed_chunk;
                } else {
+                       /* Write uncompressed */
                        out_chunk = chunk;
                        out_chunk_size = chunk_size;
                }
                *chunk_tab->cur_offset_p++ = chunk_tab->cur_offset;
                chunk_tab->cur_offset += out_chunk_size;
        } else {
+               /* Write uncompressed */
                out_chunk = chunk;
                out_chunk_size = chunk_size;
        }
@@ -550,8 +555,8 @@ write_wim_resource(struct wim_lookup_table_entry *lte,
                } else if (!hashes_equal(md, lte->hash)) {
                        ERROR("WIM resource has incorrect hash!");
                        if (lte->resource_location == RESOURCE_IN_FILE_ON_DISK) {
-                               ERROR("We were reading it from `%s'; maybe it changed "
-                                     "while we were reading it.",
+                               ERROR("We were reading it from `%"TS"'; maybe "
+                                     "it changed while we were reading it.",
                                      lte->file_on_disk);
                        }
                        ret = WIMLIB_ERR_INVALID_RESOURCE_HASH;
@@ -693,15 +698,18 @@ compress_chunks(struct message *msg, compress_func_t compress)
 {
        for (unsigned i = 0; i < msg->num_chunks; i++) {
                DEBUG2("compress chunk %u of %u", i, msg->num_chunks);
-               int ret = compress(msg->uncompressed_chunks[i],
-                                  msg->uncompressed_chunk_sizes[i],
-                                  msg->compressed_chunks[i],
-                                  &msg->compressed_chunk_sizes[i]);
-               if (ret == 0) {
+               unsigned len = compress(msg->uncompressed_chunks[i],
+                                       msg->uncompressed_chunk_sizes[i],
+                                       msg->compressed_chunks[i]);
+               if (len) {
+                       /* To be written compressed */
                        msg->out_compressed_chunks[i] = msg->compressed_chunks[i];
+                       msg->compressed_chunk_sizes[i] = len;
                } else {
+                       /* To be written uncompressed */
                        msg->out_compressed_chunks[i] = msg->uncompressed_chunks[i];
                        msg->compressed_chunk_sizes[i] = msg->uncompressed_chunk_sizes[i];
+
                }
        }
 }
@@ -1692,11 +1700,11 @@ lock_wim(WIMStruct *w, FILE *fp)
 
 static int
 open_wim_writable(WIMStruct *w, const tchar *path,
-                 bool trunc, bool readable)
+                 bool trunc, bool also_readable)
 {
        const tchar *mode;
        if (trunc)
-               if (readable)
+               if (also_readable)
                        mode = T("w+b");
                else
                        mode = T("wb");