ac89bb064a
All OS and IO operations should be moved out, leaving only some misc portable pure functions. This is useful to avoid copious CPP when doing things like Windows and Emscripten ports. Newly exposed functions to break cycles: - `restoreSignals` - `updateWindowSize`
85 lines
1.6 KiB
C++
85 lines
1.6 KiB
C++
#pragma once
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///@file
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#include "types.hh"
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#include "error.hh"
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namespace nix {
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struct Sink;
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struct Source;
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/**
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* Read the contents of a resource into a string.
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*/
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std::string readFile(int fd);
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/**
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* Wrappers arount read()/write() that read/write exactly the
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* requested number of bytes.
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*/
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void readFull(int fd, char * buf, size_t count);
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void writeFull(int fd, std::string_view s, bool allowInterrupts = true);
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/**
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* Read a line from a file descriptor.
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*/
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std::string readLine(int fd);
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/**
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* Write a line to a file descriptor.
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*/
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void writeLine(int fd, std::string s);
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/**
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* Read a file descriptor until EOF occurs.
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*/
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std::string drainFD(int fd, bool block = true, const size_t reserveSize=0);
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void drainFD(int fd, Sink & sink, bool block = true);
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/**
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* Automatic cleanup of resources.
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*/
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class AutoCloseFD
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{
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int fd;
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public:
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AutoCloseFD();
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AutoCloseFD(int fd);
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AutoCloseFD(const AutoCloseFD & fd) = delete;
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AutoCloseFD(AutoCloseFD&& fd);
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~AutoCloseFD();
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AutoCloseFD& operator =(const AutoCloseFD & fd) = delete;
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AutoCloseFD& operator =(AutoCloseFD&& fd);
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int get() const;
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explicit operator bool() const;
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int release();
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void close();
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void fsync();
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};
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class Pipe
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{
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public:
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AutoCloseFD readSide, writeSide;
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void create();
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void close();
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};
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/**
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* Close all file descriptors except those listed in the given set.
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* Good practice in child processes.
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*/
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void closeMostFDs(const std::set<int> & exceptions);
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/**
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* Set the close-on-exec flag for the given file descriptor.
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*/
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void closeOnExec(int fd);
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MakeError(EndOfFile, Error);
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}
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