Add CRC32 (ISO).

crc32.h

@@ -0,0 +1,31 @@
+/*
+ * This file is part of the Aaru Data Preservation Suite.
+ * Copyright (c) 2019-2021 Natalia Portillo.
+ *
+ * This library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of the
+ * License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+typedef struct
+{
+    uint32_t crc;
+    uint32_t table[256];
+} crc32_ctx;
+
+#define CRC32_ISO_POLY 0xEDB88320
+#define CRC32_ISO_SEED 0xFFFFFFFF
+
+crc32_ctx* crc32_init();
+int crc32_update(crc32_ctx* ctx, const uint8_t* data, uint32_t len);
+int crc32_final(crc32_ctx* ctx, uint32_t* crc);
+void crc32_free(crc32_ctx* ctx);