Method getContentFromFullBlob

internal/cache/content_cache.go:64–95

(ctx context.Context, blobID blob.ID, offset, length int64, output *gather.WriteBuffer)

}

func (c *contentCacheImpl) getContentFromFullBlob(ctx context.Context, blobID blob.ID, offset, length int64, output *gather.WriteBuffer) error {
	c.pc.exclusiveLock(string(blobID))
	defer c.pc.exclusiveUnlock(string(blobID))

	// check again to see if we perhaps lost the race and the data is now in cache.
	if c.pc.getPartial(ctx, BlobIDCacheKey(blobID), offset, length, output) {
		return nil
	}

	var blobData gather.WriteBuffer
	defer blobData.Close()

	if err := c.fetchBlobInternal(ctx, blobID, &blobData); err != nil {
		return err
	}

	if offset == 0 && length == -1 {
		_, err := blobData.Bytes().WriteTo(output)

		return errors.Wrap(err, "error copying results")
	}

	if offset < 0 || offset+length > int64(blobData.Length()) {
		return errors.Errorf("invalid (offset=%v,length=%v) for blob %q of size %v", offset, length, blobID, blobData.Length())
	}

	output.Reset()

	impossible.PanicOnError(blobData.AppendSectionTo(output, int(offset), int(length)))

	return nil
}

func (c *contentCacheImpl) fetchBlobInternal(ctx context.Context, blobID blob.ID, blobData *gather.WriteBuffer) error {
	// read the entire blob