Implement I/O abstraction layer. Finally.
diff --git a/lib/zip_io_util.c b/lib/zip_io_util.c
new file mode 100644
index 0000000..3f4970c
--- /dev/null
+++ b/lib/zip_io_util.c
@@ -0,0 +1,211 @@
+/*
+ zip_io_util.c -- I/O helper functions
+ Copyright (C) 1999-2014 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 <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "zipint.h"
+
+zip_uint16_t
+_zip_get_16(const zip_uint8_t **a)
+{
+ zip_uint16_t ret;
+
+ ret = (zip_uint16_t)((*a)[0]+((*a)[1]<<8));
+ *a += 2;
+
+ return ret;
+}
+
+
+zip_uint32_t
+_zip_get_32(const zip_uint8_t **a)
+{
+ zip_uint32_t ret;
+
+ ret = ((((((zip_uint32_t)(*a)[3]<<8)+(*a)[2])<<8)+(*a)[1])<<8)+(*a)[0];
+ *a += 4;
+
+ return ret;
+}
+
+
+zip_uint64_t
+_zip_get_64(const zip_uint8_t **a)
+{
+ zip_uint64_t x, y;
+
+ x = ((((((zip_uint64_t)(*a)[3]<<8)+(*a)[2])<<8)+(*a)[1])<<8)+(*a)[0];
+ *a += 4;
+ y = ((((((zip_uint64_t)(*a)[3]<<8)+(*a)[2])<<8)+(*a)[1])<<8)+(*a)[0];
+ *a += 4;
+
+ return x+(y<<32);
+}
+
+int
+_zip_read(struct zip_source *src, zip_uint8_t *b, zip_uint64_t length, struct zip_error *error)
+{
+ zip_int64_t n;
+
+ if (length > ZIP_INT64_MAX) {
+ zip_error_set(error, ZIP_ER_INTERNAL, 0);
+ return -1;
+ }
+
+ if ((n = zip_source_read(src, b, length)) < 0) {
+ zip_error_set_from_source(error, src);
+ return -1;
+ }
+
+ if (n < (zip_int64_t)length) {
+ zip_error_set(error, ZIP_ER_EOF, 0);
+ return -1;
+ }
+
+ return 0;
+}
+
+
+zip_uint8_t *
+_zip_read_data(const zip_uint8_t **buf, struct zip_source *src, size_t len, int nulp, struct zip_error *error)
+{
+ zip_uint8_t *r;
+
+ if (len == 0 && nulp == 0)
+ return NULL;
+
+ r = (zip_uint8_t *)malloc(nulp ? len+1 : len);
+ if (!r) {
+ zip_error_set(error, ZIP_ER_MEMORY, 0);
+ return NULL;
+ }
+
+ if (buf) {
+ memcpy(r, *buf, len);
+ *buf += len;
+ }
+ else {
+ if (_zip_read(src, r, len, error) < 0) {
+ free(r);
+ return NULL;
+ }
+ }
+
+ if (nulp) {
+ zip_uint8_t *o;
+ /* replace any in-string NUL characters with spaces */
+ r[len] = 0;
+ for (o=r; o<r+len; o++)
+ if (*o == '\0')
+ *o = ' ';
+ }
+
+ return r;
+}
+
+
+struct zip_string *
+_zip_read_string(const zip_uint8_t **buf, struct zip_source *src, zip_uint16_t len, int nulp, struct zip_error *error)
+{
+ zip_uint8_t *raw;
+ struct zip_string *s;
+
+ if ((raw=_zip_read_data(buf, src, len, nulp, error)) == NULL)
+ return NULL;
+
+ s = _zip_string_new(raw, len, ZIP_FL_ENC_GUESS, error);
+ free(raw);
+ return s;
+}
+
+
+
+
+void
+_zip_put_16(zip_uint8_t **p, zip_uint16_t i)
+{
+ *((*p)++) = i&0xff;
+ *((*p)++) = (i>>8)&0xff;
+}
+
+
+void
+_zip_put_32(zip_uint8_t **p, zip_uint32_t i)
+{
+ *((*p)++) = i&0xff;
+ *((*p)++) = (i>>8)&0xff;
+ *((*p)++) = (i>>16)&0xff;
+ *((*p)++) = (i>>24)&0xff;
+}
+
+
+void
+_zip_put_64(zip_uint8_t **p, zip_uint64_t i)
+{
+ *((*p)++) = i&0xff;
+ *((*p)++) = (i>>8)&0xff;
+ *((*p)++) = (i>>16)&0xff;
+ *((*p)++) = (i>>24)&0xff;
+ *((*p)++) = (i>>32)&0xff;
+ *((*p)++) = (i>>40)&0xff;
+ *((*p)++) = (i>>48)&0xff;
+ *((*p)++) = (i>>56)&0xff;
+}
+
+
+void
+_zip_put_data(zip_uint8_t **p, const char *s, size_t len)
+{
+ memcpy(*p, s, len);
+ *p += len;
+}
+
+
+int
+_zip_write(struct zip *za, const void *data, zip_uint64_t length)
+{
+ zip_int64_t n;
+
+ if ((n = zip_source_write(za->src, data, length)) < 0) {
+ zip_error_set_from_source(&za->error, za->src);
+ return -1;
+ }
+ if ((zip_uint64_t)n != length) {
+ zip_error_set(&za->error, ZIP_ER_WRITE, EINTR);
+ return -1;
+ }
+
+ return 0;
+}
