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/* Copyright (c) 2015 Goldstein Lyor, All Rights Reserved
*
* The contents of this file is dual-licensed under 2
* alternative Open Source/Free licenses: LGPL 2.1 or later and
* Apache License 2.0. (starting with JNA version 4.0.0).
*
* You can freely decide which license you want to apply to
* the project.
*
* You may obtain a copy of the LGPL License at:
*
* http://www.gnu.org/licenses/licenses.html
*
* A copy is also included in the downloadable source code package
* containing JNA, in file "LGPL2.1".
*
* You may obtain a copy of the Apache License at:
*
* http://www.apache.org/licenses/
*
* A copy is also included in the downloadable source code package
* containing JNA, in file "AL2.0".
*/
package com.sun.jna.platform.unix;
import com.sun.jna.IntegerType;
import com.sun.jna.Native;
import com.sun.jna.Pointer;
/**
* Note: we are using this "intermediate" API in order to allow
* Linux-like O/S-es to implement the same API, but maybe using a different
* library name
* @author Lyor Goldstein
*/
public interface LibCAPI extends Reboot, Resource {
/**
* This is an unsigned integer type used to represent the sizes of objects.
*/
class size_t extends IntegerType {
public static final size_t ZERO = new size_t();
private static final long serialVersionUID = 1L;
public size_t() {
this(0);
}
public size_t(long value) {
super(Native.SIZE_T_SIZE, value, true);
}
}
/**
* This is a signed integer type used for a count of bytes or an error
* indication.
*/
class ssize_t extends IntegerType {
public static final ssize_t ZERO = new ssize_t();
private static final long serialVersionUID = 1L;
public ssize_t() {
this(0);
}
public ssize_t(long value) {
super(Native.SIZE_T_SIZE, value, false);
}
}
// see man(2) get/set uid/gid
int getuid();
int geteuid();
int getgid();
int getegid();
int setuid(int uid);
int seteuid(int uid);
int setgid(int gid);
int setegid(int gid);
// see man(2) get/set hostname
int HOST_NAME_MAX = 255; // not including the '\0'
int gethostname(byte[] name, int len);
int sethostname(String name, int len);
// see man(2) get/set domainname
int getdomainname(byte[] name, int len);
int setdomainname(String name, int len);
/**
* @param name Environment variable name
* @return Returns the value in the environment, or {@code null} if there
* is no match for the name
* @see getenv(3)
*/
String getenv(String name);
/**
* Update or add a variable in the environment of the calling process.
* @param name Environment variable name
* @param value Required value
* @param overwrite If the environment variable already exists and the
* value of {@code overwrite} is non-zero, the function shall return
* success and the environment shall be updated. If the environment
* variable already exists and the value of {@code overwrite} is zero, the
* function shall return success and the environment shall remain unchanged.
* @return Upon successful completion, zero shall be returned. Otherwise,
* -1 shall be returned, {@code errno} set to indicate the error, and the
* environment shall be unchanged
* @see getenv(3)
*/
int setenv(String name, String value, int overwrite);
/**
* @param name Environment variable name - If the named variable does not
* exist in the current environment, the environment shall be unchanged
* and the function is considered to have completed successfully.
* @return Upon successful completion, zero shall be returned. Otherwise,
* -1 shall be returned, {@code errno} set to indicate the error, and the
* environment shall be unchanged
* @see getenv(3)
*/
int unsetenv(String name);
/**
* The getloadavg() function returns the number of processes in the system
* run queue averaged over various periods of time. Up to nelem samples are
* retrieved and assigned to successive elements of loadavg[]. The system
* imposes a maximum of 3 samples, representing averages over the last 1, 5,
* and 15 minutes, respectively.
* @param loadavg An array of doubles which will be filled with the results
* @param nelem Number of samples to return
* @return If the load average was unobtainable, -1 is returned; otherwise,
* the number of samples actually retrieved is returned.
* @see getloadavg(3)
*/
int getloadavg(double[] loadavg, int nelem);
/**
* Closes a file descriptor, so that it no longer refers to any file and may be
* reused. Any record locks held on the file it was associated with, and owned
* by the process, are removed (regardless of the file descriptor that was used
* to obtain the lock).
*
* If {@code fd} is the last file descriptor referring to the underlying open
* file description, the resources associated with the open file description are
* freed; if the file descriptor was the last reference to a file which has been
* removed using {@code unlink}, the file is deleted.
*
* @param fd
* a file descriptor
* @return returns zero on success. On error, -1 is returned, and {@code errno}
* is set appropriately.
*
* {@code close()} should not be retried after an error.
*/
int close(int fd);
/**
* Flushes changes made to the in-core copy of a file that was mapped into
* memory using {@link LibCUtil#mmap(Pointer, long, int, int, int, long)} back
* to the filesystem. Without use of this call, there is no guarantee that
* changes are written back before {@link #munmap(Pointer, size_t)} is called.
* To be more precise, the part of the file that corresponds to the memory area
* starting at {@code addr} and having length {@code length} is updated.
*
* @param addr
* The start of the memory area to sync to the filesystem.
* @param length
* The length of the memory area to sync to the filesystem.
* @param flags
* The flags argument should specify exactly one of {@code MS_ASYNC}
* and {@code MS_SYNC}, and may additionally include the
* {@code MS_INVALIDATE} bit.
* @return On success, zero is returned. On error, -1 is returned, and
* {@code errno} is set appropriately.
*/
int msync(Pointer addr, size_t length, int flags);
/**
* Deletes the mappings for the specified address range, and causes further
* references to addresses within the range to generate invalid memory
* references. The region is also automatically unmapped when the process is
* terminated. On the other hand, closing the file descriptor does not unmap the
* region.
*
* It is not an error if the indicated range does not contain any mapped pages.
*
* @param addr
* The base address from which to delete mappings. The address addr
* must be a multiple of the page size (but length need not be).
* @param length
* The length from the base address to delete mappings. All pages
* containing a part of the indicated range are unmapped, and
* subsequent references to these pages will generate
* {@code SIGSEGV}.
* @return On success, returns 0. On failure, it returns -1, and {@code errno}
* is set to indicate the cause of the error (probably to
* {@code EINVAL}).
*/
int munmap(Pointer addr, size_t length);
}