github.com/inspektor-gadget/inspektor-gadget@v0.28.1/pkg/gadgets/top/top.go (about)

     1  // Copyright 2022 The Inspektor Gadget authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package top
    16  
    17  import (
    18  	"fmt"
    19  	"time"
    20  
    21  	"github.com/inspektor-gadget/inspektor-gadget/pkg/columns"
    22  	columnssort "github.com/inspektor-gadget/inspektor-gadget/pkg/columns/sort"
    23  )
    24  
    25  const (
    26  	MaxRowsDefault  = 20
    27  	IntervalDefault = 1
    28  
    29  	IntervalParam = "interval"
    30  	MaxRowsParam  = "max_rows"
    31  	SortByParam   = "sort_by"
    32  )
    33  
    34  type Event[T any] struct {
    35  	Error string `json:"error,omitempty"`
    36  	Stats []*T   `json:"stats,omitempty"`
    37  }
    38  
    39  func SortStats[T any](stats []*T, sortBy []string, colMap *columns.ColumnMap[T]) {
    40  	columnssort.SortEntries(*colMap, stats, sortBy)
    41  }
    42  
    43  // ComputeIterations returns the number of iterations to perform to get the
    44  // desired timeout. It returns zero if timeout is zero.
    45  func ComputeIterations(interval, timeout time.Duration) (int, error) {
    46  	if timeout <= 0 {
    47  		return 0, nil
    48  	}
    49  	if timeout < interval {
    50  		return 0, fmt.Errorf("timeout must be greater than interval")
    51  	}
    52  	if timeout%interval != 0 {
    53  		return 0, fmt.Errorf("timeout must be a multiple of interval")
    54  	}
    55  	return int(timeout / interval), nil
    56  }