API cleanup, be less strict with file name arguments.
diff --git a/lib/zip_file_replace.c b/lib/zip_file_replace.c
new file mode 100644
index 0000000..14da8ad
--- /dev/null
+++ b/lib/zip_file_replace.c
@@ -0,0 +1,93 @@
+/*
+ zip_file_replace.c -- replace file via callback function
+ Copyright (C) 1999-2012 Dieter Baron and Thomas Klausner
+
+ This file is part of libzip, a library to manipulate ZIP archives.
+ The authors can be contacted at <libzip@nih.at>
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ 3. The names of the authors may not be used to endorse or promote
+ products derived from this software without specific prior
+ written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
+ OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
+ DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+ IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+
+#include "zipint.h"
+
+
+
+ZIP_EXTERN int
+zip_file_replace(struct zip *za, zip_uint64_t idx, struct zip_source *source, zip_flags_t flags)
+{
+ if (idx >= za->nentry || source == NULL) {
+ _zip_error_set(&za->error, ZIP_ER_INVAL, 0);
+ return -1;
+ }
+
+ if (_zip_file_replace(za, idx, NULL, source, flags) == -1)
+ return -1;
+
+ return 0;
+}
+
+
+
+
+/* NOTE: Signed due to -1 on error. See zip_add.c for more details. */
+
+zip_int64_t
+_zip_file_replace(struct zip *za, zip_uint64_t idx, const char *name, struct zip_source *source, zip_flags_t flags)
+{
+ zip_uint64_t za_nentry_prev;
+ if (ZIP_IS_RDONLY(za)) {
+ _zip_error_set(&za->error, ZIP_ER_RDONLY, 0);
+ return -1;
+ }
+
+ za_nentry_prev = za->nentry;
+ if (idx == ZIP_UINT64_MAX) {
+ zip_int64_t i;
+
+ /* create and use new entry, used by zip_add */
+ if ((i=_zip_add_entry(za)) < 0)
+ return -1;
+ idx = i;
+ }
+
+ if (name && _zip_set_name(za, idx, name, flags) != 0) {
+ if (za->nentry != za_nentry_prev) {
+ _zip_entry_finalize(za->entry+idx);
+ za->nentry = za_nentry_prev;
+ }
+ return -1;
+ }
+
+ /* does not change any name related data, so we can do it here;
+ * needed for a double add of the same file name */
+ _zip_unchange_data(za->entry+idx);
+
+ za->entry[idx].source = source;
+
+ return idx;
+}
