inspektor-gadget

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// Copyright 2023 The Inspektor Gadget authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//     http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package tracer
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var flagNames = []string{
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	"O_CREAT",
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	"O_EXCL",
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	"O_NOCTTY",
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	"O_TRUNC",
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	"O_APPEND",
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	"O_NONBLOCK",
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	"O_DSYNC",
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	"O_FASYNC",
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	"O_DIRECT",
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	"O_LARGEFILE",
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	"O_DIRECTORY",
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	"O_NOFOLLOW",
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	"O_NOATIME",
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	"O_CLOEXEC",
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}
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func DecodeFlags(flags int32) []string {
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	flagsStr := []string{}
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	// We first need to deal with the first 3 bits which indicates access mode.
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	switch flags & 0b11 {
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	case 0:
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		flagsStr = append(flagsStr, "O_RDONLY")
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	case 1:
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		flagsStr = append(flagsStr, "O_WRONLY")
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	case 2:
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		flagsStr = append(flagsStr, "O_RDWR")
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	}
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	// Then, we need to remove the last 6 bits and we can deal with the other
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	// flags.
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	// Indeed, O_CREAT is defined as 00000100, see:
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	// https://github.com/torvalds/linux/blob/9d646009f65d/include/uapi/asm-generic/fcntl.h#L24
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	flags >>= 6
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	for i, val := range flagNames {
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		if (1<<i)&flags == 0 {
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			continue
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		}
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		flagsStr = append(flagsStr, val)
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	}
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	return flagsStr
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}
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