github.com/cloudwego/frugal@v0.1.15/internal/utils/buffer_emu.go (about)

     1  /*
     2   * Copyright 2022 ByteDance Inc.
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *     http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  
    17  package utils
    18  
    19  import (
    20      `unsafe`
    21  
    22      `github.com/cloudwego/frugal/internal/atm/hir`
    23      `github.com/cloudwego/frugal/internal/rt`
    24      `github.com/cloudwego/frugal/iov`
    25  )
    26  
    27  func emu_wbuf(ctx hir.CallContext) (v iov.BufferWriter) {
    28      (*rt.GoIface)(unsafe.Pointer(&v)).Itab = ctx.Itab()
    29      (*rt.GoIface)(unsafe.Pointer(&v)).Value = ctx.Data()
    30      return
    31  }
    32  
    33  func emu_bytes(ctx hir.CallContext, i int) (v []byte) {
    34      return rt.BytesFrom(ctx.Ap(i), int(ctx.Au(i + 1)), int(ctx.Au(i + 2)))
    35  }
    36  
    37  func emu_seterr(ctx hir.CallContext, err error) {
    38      vv := (*rt.GoIface)(unsafe.Pointer(&err))
    39      ctx.Rp(0, unsafe.Pointer(vv.Itab))
    40      ctx.Rp(1, vv.Value)
    41  }
    42  
    43  func emu_icall_ZeroCopyWriter_WriteDirect(ctx hir.CallContext) {
    44      if !ctx.Verify("*iii", "**") {
    45          panic("invalid ZeroCopyWriter.WriteDirect call")
    46      } else {
    47          emu_seterr(ctx, emu_wbuf(ctx).WriteDirect(emu_bytes(ctx, 0), int(ctx.Au(3))))
    48      }
    49  }