diff --git a/physfs.c b/physfs.c index ad2f192..ad2599a 100644 --- a/physfs.c +++ b/physfs.c @@ -1875,7 +1875,22 @@ int PHYSFS_seek(PHYSFS_file *handle, PHYSFS_uint64 pos) { FileHandle *h = (FileHandle *) handle->opaque; BAIL_IF_MACRO(!PHYSFS_flush(handle), NULL, 0); - h->buffill = h->bufpos = 0; /* just in case. */ + + if (h->buffer && h->forReading) + { + /* avoid throwing away our precious buffer if seeking within it. */ + PHYSFS_sint64 offset = pos - PHYSFS_tell(handle); + if ( /* seeking within the already-buffered range? */ + ((offset >= 0) && (offset <= h->buffill - h->bufpos)) /* forwards */ + || ((offset < 0) && (-offset <= h->bufpos)) /* backwards */ ) + { + h->bufpos += offset; + return(1); /* successful seek */ + } /* if */ + } /* if */ + + /* we have to fall back to a 'raw' seek. */ + h->buffill = h->bufpos = 0; return(h->funcs->seek(h, pos)); } /* PHYSFS_seek */