text: /*
   * Copyright 1998-2018 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the Apache License 2.0 (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <openssl/objects.h>
  #include <openssl/comp.h>
  #include <openssl/err.h>
  #include "comp_lcl.h"
  
  COMP_CTX *COMP_CTX_new(COMP_METHOD *meth)
  {
      COMP_CTX *ret;
  
      if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL) {
          COMPerr(COMP_F_COMP_CTX_NEW, ERR_R_MALLOC_FAILURE);
          return NULL;
      }
      ret->meth = meth;
      if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
          OPENSSL_free(ret);
          ret = NULL;
      }
      return ret;
  }
  
  const COMP_METHOD *COMP_CTX_get_method(const COMP_CTX *ctx)
  {
      return ctx->meth;
  }
  
  int COMP_get_type(const COMP_METHOD *meth)
  {
      return meth->type;
  }
  
  const char *COMP_get_name(const COMP_METHOD *meth)
  {
      return meth->name;
  }
  
  void COMP_CTX_free(COMP_CTX *ctx)
  {
      if (ctx == NULL)
          return;
      if (ctx->meth->finish != NULL)
          ctx->meth->finish(ctx);
  
      OPENSSL_free(ctx);
  }
  
  int COMP_compress_block(COMP_CTX *ctx, unsigned char *out, int olen,
                          unsigned char *in, int ilen)
  {
      int ret;
      if (ctx->meth->compress == NULL) {
          return -1;
      }
      ret = ctx->meth->compress(ctx, out, olen, in, ilen);
      if (ret > 0) {
          ctx->compress_in += ilen;
          ctx->compress_out += ret;
      }
      return ret;
  }
  
  int COMP_expand_block(COMP_CTX *ctx, unsigned char *out, int olen,
                        unsigned char *in, int ilen)
  {
      int ret;
  
      if (ctx->meth->expand == NULL) {
          return -1;
      }
      ret = ctx->meth->expand(ctx, out, olen, in, ilen);
      if (ret > 0) {
          ctx->expand_in += ilen;
          ctx->expand_out += ret;
      }
      return ret;
  }
  
  int COMP_CTX_get_type(const COMP_CTX* comp)
  {
      return comp->meth ? comp->meth->type : NID_undef;
  }
  