github.com/cilium/ebpf@v0.15.1-0.20240517100537-8079b37aa138/cmd/bpf2go/flags.go (about)

     1  package main
     2  
     3  import (
     4  	"flag"
     5  	"go/build/constraint"
     6  )
     7  
     8  // buildTags is a comma-separated list of build tags.
     9  //
    10  // This follows the pre-Go 1.17 syntax and is kept for compatibility reasons.
    11  type buildTags struct {
    12  	Expr constraint.Expr
    13  }
    14  
    15  var _ flag.Value = (*buildTags)(nil)
    16  
    17  func (bt *buildTags) String() string {
    18  	if bt.Expr == nil {
    19  		return ""
    20  	}
    21  
    22  	return (bt.Expr).String()
    23  }
    24  
    25  func (bt *buildTags) Set(value string) error {
    26  	ct, err := constraint.Parse("// +build " + value)
    27  	if err != nil {
    28  		return err
    29  	}
    30  
    31  	bt.Expr = ct
    32  	return nil
    33  }
    34  
    35  func andConstraints(x, y constraint.Expr) constraint.Expr {
    36  	if x == nil {
    37  		return y
    38  	}
    39  
    40  	if y == nil {
    41  		return x
    42  	}
    43  
    44  	return &constraint.AndExpr{X: x, Y: y}
    45  }
    46  
    47  func orConstraints(x, y constraint.Expr) constraint.Expr {
    48  	if x == nil {
    49  		return y
    50  	}
    51  
    52  	if y == nil {
    53  		return x
    54  	}
    55  
    56  	return &constraint.OrExpr{X: x, Y: y}
    57  }