extract.c: simplify extract_from_tmpfile()
authorEric Biggers <ebiggers3@gmail.com>
Sat, 30 May 2015 20:48:21 +0000 (15:48 -0500)
committerEric Biggers <ebiggers3@gmail.com>
Fri, 5 Jun 2015 03:05:38 +0000 (22:05 -0500)
Since win32_apply.c no longer will create external backing references at
blob extraction time, extract_from_tmpfile() can be simplified.

include/wimlib/blob_table.h
src/extract.c

index 9dfca8d..6dbbe55 100644 (file)
@@ -353,7 +353,7 @@ extern int
 cmp_blobs_by_sequential_order(const void *p1, const void *p2);
 
 static inline const struct blob_extraction_target *
-blob_extraction_targets(struct blob_descriptor *blob)
+blob_extraction_targets(const struct blob_descriptor *blob)
 {
        if (blob->out_refcnt <= ARRAY_LEN(blob->inline_blob_extraction_targets))
                return blob->inline_blob_extraction_targets;
index cf8a2c9..04d0b79 100644 (file)
@@ -384,61 +384,31 @@ extract_chunk_wrapper(const void *chunk, size_t size, void *_ctx)
        return call_consume_chunk(chunk, size, ctx->saved_cbs);
 }
 
+/* Copy the blob's data from the temporary file to each of its targets.
+ *
+ * This is executed only in the very uncommon case that a blob is being
+ * extracted to more than MAX_OPEN_FILES targets!  */
 static int
-extract_from_tmpfile(const tchar *tmpfile_name, struct apply_ctx *ctx)
+extract_from_tmpfile(const tchar *tmpfile_name,
+                    const struct blob_descriptor *orig_blob,
+                    const struct read_blob_callbacks *cbs)
 {
        struct blob_descriptor tmpfile_blob;
-       struct blob_descriptor *orig_blob = ctx->cur_blob;
-       const struct read_blob_callbacks *cbs = ctx->saved_cbs;
+       const struct blob_extraction_target *targets = blob_extraction_targets(orig_blob);
        int ret;
-       const u32 orig_refcnt = orig_blob->out_refcnt;
-
-       BUILD_BUG_ON(MAX_OPEN_FILES <
-                    ARRAY_LEN(orig_blob->inline_blob_extraction_targets));
-
-       struct blob_extraction_target *targets = orig_blob->blob_extraction_targets;
-
-       /* Copy the blob's data from the temporary file to each of its targets.
-        *
-        * This is executed only in the very uncommon case that a blob is being
-        * extracted to more than MAX_OPEN_FILES targets!  */
 
        memcpy(&tmpfile_blob, orig_blob, sizeof(struct blob_descriptor));
        tmpfile_blob.blob_location = BLOB_IN_FILE_ON_DISK;
-       tmpfile_blob.file_on_disk = ctx->tmpfile_name;
-       ret = 0;
-       for (u32 i = 0; i < orig_refcnt; i++) {
-
-               /* Note: it usually doesn't matter whether we pass the original
-                * blob descriptor to callbacks provided by the extraction
-                * backend as opposed to the tmpfile blob descriptor, since they
-                * shouldn't actually read data from the blob other than through
-                * the read_blob_with_cbs() call below.  But for
-                * WIMLIB_EXTRACT_FLAG_WIMBOOT mode on Windows it does matter
-                * because it needs access to the original WIM resource
-                * descriptor in order to create the external backing reference.
-                */
-
-               orig_blob->out_refcnt = 1;
-               orig_blob->inline_blob_extraction_targets[0] = targets[i];
-
-               ret = call_begin_blob(orig_blob, cbs);
-               if (ret)
-                       break;
+       tmpfile_blob.file_on_disk = (tchar *)tmpfile_name;
+       tmpfile_blob.out_refcnt = 1;
 
-               struct read_blob_callbacks wrapper_cbs = {
-                       .consume_chunk  = cbs->consume_chunk,
-                       .ctx            = cbs->ctx,
-               };
-               ret = read_blob_with_cbs(&tmpfile_blob, &wrapper_cbs);
-
-               ret = call_end_blob(orig_blob, ret, cbs);
+       for (u32 i = 0; i < orig_blob->out_refcnt; i++) {
+               tmpfile_blob.inline_blob_extraction_targets[0] = targets[i];
+               ret = read_blob_with_cbs(&tmpfile_blob, cbs);
                if (ret)
-                       break;
+                       return ret;
        }
-       FREE(targets);
-       orig_blob->out_refcnt = 0;
-       return ret;
+       return 0;
 }
 
 static int
@@ -449,7 +419,8 @@ end_extract_blob_wrapper(struct blob_descriptor *blob, int status, void *_ctx)
        if (unlikely(filedes_valid(&ctx->tmpfile_fd))) {
                filedes_close(&ctx->tmpfile_fd);
                if (!status)
-                       status = extract_from_tmpfile(ctx->tmpfile_name, ctx);
+                       status = extract_from_tmpfile(ctx->tmpfile_name, blob,
+                                                     ctx->saved_cbs);
                filedes_invalidate(&ctx->tmpfile_fd);
                tunlink(ctx->tmpfile_name);
                FREE(ctx->tmpfile_name);