github.com/thediveo/gons@v0.9.9/gons.go (about)

     1  // Copyright 2019 Harald Albrecht.
     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  //go:build linux
    16  // +build linux
    17  
    18  package gons
    19  
    20  /*
    21  extern void gonamespaces(void);
    22  extern char *gonsmsg;
    23  void __attribute__((constructor)) init(void) {
    24  	gonamespaces();
    25  }
    26  */
    27  import "C"
    28  
    29  // NamespaceSwitchError reports unsuccessful namespace switching during
    30  // startup.
    31  type NamespaceSwitchError struct {
    32  	details string
    33  }
    34  
    35  // Error returns a description of the failure causing the initial namespace
    36  // switching to abort.
    37  func (e *NamespaceSwitchError) Error() string {
    38  	if e == nil {
    39  		return "<nil>"
    40  	}
    41  	return e.details
    42  }
    43  
    44  // Status returns nil if there were no problems switching namespaces during
    45  // initial startup; otherwise, it returns a NamespaceSwitchError with a detail
    46  // description.
    47  func Status() error {
    48  	if C.gonsmsg == nil {
    49  		return nil
    50  	}
    51  	return &NamespaceSwitchError{
    52  		details: C.GoString(C.gonsmsg),
    53  	}
    54  }