/* compress.c -- compress a memory buffer

 * Copyright (C) 1995-2005, 2014, 2016 Jean-loup Gailly, Mark Adler

 * For conditions of distribution and use, see copyright notice in zlib.h

 */

#include "zbuild.h"

#include "zutil.h"

#include <limits.h>

/* ===========================================================================

 *  Architecture-specific hooks.

 */

#ifdef S390_DFLTCC_DEFLATE

#  include "arch/s390/dfltcc_common.h"

#else

/* Returns the upper bound on compressed data length based on uncompressed data length, assuming default settings.

 * Zero means that arch-specific deflation code behaves identically to the regular zlib-ng algorithms. */

#  define DEFLATE_BOUND_COMPLEN(source_len) 0

#endif

/* ===========================================================================

     Compresses the source buffer into the destination buffer. The level

   parameter has the same meaning as in deflateInit.  sourceLen is the byte

   length of the source buffer. Upon entry, destLen is the total size of the

   destination buffer, which must be at least 0.1% larger than sourceLen plus

   12 bytes. Upon exit, destLen is the actual size of the compressed buffer.

     compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough

   memory, Z_BUF_ERROR if there was not enough room in the output buffer,

   Z_STREAM_ERROR if the level parameter is invalid.

*/

#ifdef ZLIB_COMPAT

int Z_EXPORT PREFIX(compress2_z)(unsigned char *dest, z_size_t *destLen, const unsigned char *source, z_size_t sourceLen,

                        int level) {

#else

int32_t Z_EXPORT PREFIX(compress2)(uint8_t *dest, size_t *destLen, const uint8_t *source, size_t sourceLen, int32_t level) {

#endif

    PREFIX3(stream) stream;

    int err;

    z_size_t left;

    if ((sourceLen > 0 && source == NULL) ||

        destLen == NULL || (*destLen > 0 && dest == NULL))

        return Z_STREAM_ERROR;

    left = *destLen;

    *destLen = 0;

    stream.zalloc = NULL;

    stream.zfree = NULL;

    stream.opaque = NULL;

    err = PREFIX(deflateInit)(&stream, level);

    if (err != Z_OK)

        return err;

    stream.next_out = dest;

    stream.avail_out = 0;

    stream.next_in = (z_const unsigned char *)source;

    stream.avail_in = 0;

    do {

        if (stream.avail_out == 0) {

            stream.avail_out = (unsigned int)MIN(UINT_MAX, left);

            left -= stream.avail_out;

        }

        if (stream.avail_in == 0) {

            stream.avail_in = (unsigned int)MIN(UINT_MAX, sourceLen);

            sourceLen -= stream.avail_in;

        }

        err = PREFIX(deflate)(&stream, sourceLen ? Z_NO_FLUSH : Z_FINISH);

    } while (err == Z_OK);

    *destLen = stream.total_out;

    PREFIX(deflateEnd)(&stream);

    return err == Z_STREAM_END ? Z_OK : err;

}

/* ===========================================================================

 */

z_int32_t Z_EXPORT PREFIX(compress)(unsigned char *dest, z_uintmax_t *destLen, const unsigned char *source, z_uintmax_t sourceLen) {

    return PREFIX(compress2)(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);

}

/* ===========================================================================

   If the default memLevel or windowBits for deflateInit() is changed, then

   this function needs to be updated.

 */

#ifdef ZLIB_COMPAT

z_size_t Z_EXPORT PREFIX(compressBound_z)(z_size_t sourceLen) {

#else

size_t Z_EXPORT PREFIX(compressBound)(size_t sourceLen) {

#endif

    z_size_t complen = DEFLATE_BOUND_COMPLEN(sourceLen);

    z_size_t bound;

    if (complen > 0) {

        /* Architecture-specific code provided an upper bound. */

        bound = complen + ZLIB_WRAPLEN;

        return bound < sourceLen ? (z_size_t)-1 : bound;

    }

#ifndef NO_QUICK_STRATEGY

    bound = sourceLen                      /* The source size itself */

      + (sourceLen == 0 ? 1 : 0)           /* Always at least one byte for any input */

      + (sourceLen < 9 ? 1 : 0)            /* One extra byte for lengths less than 9 */

      + DEFLATE_QUICK_OVERHEAD(sourceLen)  /* Source encoding overhead, padded to next full byte */

      + DEFLATE_BLOCK_OVERHEAD             /* Deflate block overhead bytes */

      + ZLIB_WRAPLEN;                      /* zlib wrapper */

#else

    bound = sourceLen + (sourceLen >> 4) + 7 + ZLIB_WRAPLEN;

#endif

    return bound < sourceLen ? (z_size_t)-1 : bound;

}

#ifdef ZLIB_COMPAT

unsigned long Z_EXPORT PREFIX(compressBound)(unsigned long sourceLen) {

    z_size_t bound = PREFIX(compressBound_z)(sourceLen);

    return (unsigned long)MIN(ULONG_MAX, bound);

}

int Z_EXPORT PREFIX(compress2)(unsigned char *dest, unsigned long *destLen, const unsigned char *source,

                              unsigned long sourceLen, int level) {

    z_size_t got = destLen ? *destLen : 0;

    int ret = PREFIX(compress2_z)(dest, &got, source, sourceLen, level);

    if (destLen)

        *destLen = (unsigned long)got;

    return ret;

}

z_int32_t Z_EXPORT PREFIX(compress_z)(unsigned char *dest, z_size_t *destLen, const unsigned char *source,

                                      z_size_t sourceLen) {

    return PREFIX(compress2_z)(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION);

}

#endif