Rename ffmpeg-4.2-fit to ffmpeg-4-fit

trunk/3rdparty/ffmpeg-4-fit/libavutil/rc4.h

@@ -0,0 +1,66 @@
+/*
+ * RC4 encryption/decryption/pseudo-random number generator
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVUTIL_RC4_H
+#define AVUTIL_RC4_H
+
+#include <stdint.h>
+
+/**
+ * @defgroup lavu_rc4 RC4
+ * @ingroup lavu_crypto
+ * @{
+ */
+
+typedef struct AVRC4 {
+    uint8_t state[256];
+    int x, y;
+} AVRC4;
+
+/**
+ * Allocate an AVRC4 context.
+ */
+AVRC4 *av_rc4_alloc(void);
+
+/**
+ * @brief Initializes an AVRC4 context.
+ *
+ * @param key_bits must be a multiple of 8
+ * @param decrypt 0 for encryption, 1 for decryption, currently has no effect
+ * @return zero on success, negative value otherwise
+ */
+int av_rc4_init(struct AVRC4 *d, const uint8_t *key, int key_bits, int decrypt);
+
+/**
+ * @brief Encrypts / decrypts using the RC4 algorithm.
+ *
+ * @param count number of bytes
+ * @param dst destination array, can be equal to src
+ * @param src source array, can be equal to dst, may be NULL
+ * @param iv not (yet) used for RC4, should be NULL
+ * @param decrypt 0 for encryption, 1 for decryption, not (yet) used
+ */
+void av_rc4_crypt(struct AVRC4 *d, uint8_t *dst, const uint8_t *src, int count, uint8_t *iv, int decrypt);
+
+/**
+ * @}
+ */
+
+#endif /* AVUTIL_RC4_H */