xnu-1504.9.17.tar.gz

[apple/xnu.git] / bsd / sys / sem.h

diff --git a/bsd/sys/sem.h b/bsd/sys/sem.h
index 9aa6bd8efcf02f439a053e056ebb1546673ded4a..18eeb2061291360e583cb4795ed7aaaabfed02c2 100644 (file)
--- a/bsd/sys/sem.h
+++ b/bsd/sys/sem.h
@@ -1,16 +1,19 @@
 /*
 /*

- * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2007 Apple Inc. All rights reserved.

  *
  *

- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@

  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in

- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ * 
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.

  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER


@@ -20,7 +23,7 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 

- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@

  */
 /*     $NetBSD: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $      */
 
  */
 /*     $NetBSD: sem.h,v 1.5 1994/06/29 06:45:15 cgd Exp $      */
 


@@ -28,224 +31,198 @@
  * SVID compatible sem.h file
  *
  * Author:  Daniel Boulet
  * SVID compatible sem.h file
  *
  * Author:  Daniel Boulet

- */
-/*

  * John Bellardo modified the implementation for Darwin. 12/2000
  */
 
 #ifndef _SYS_SEM_H_
 #define _SYS_SEM_H_
 
  * John Bellardo modified the implementation for Darwin. 12/2000
  */
 
 #ifndef _SYS_SEM_H_
 #define _SYS_SEM_H_
 

-#include <sys/appleapiopts.h>
-#include <sys/ipc.h>
-
-struct sem {
-       u_short semval;         /* semaphore value */
-       pid_t   sempid;         /* pid of last operation */
-       u_short semncnt;        /* # awaiting semval > cval */
-       u_short semzcnt;        /* # awaiting semval = 0 */
-};
-
-struct semid_ds {
-       struct  ipc_perm sem_perm;      /* operation permission struct */
-       struct  sem *sem_base;  /* pointer to first semaphore in set */
-       u_short sem_nsems;      /* number of sems in set */
-       time_t  sem_otime;      /* last operation time */
-       long    sem_pad1;       /* SVABI/386 says I need this here */
-       time_t  sem_ctime;      /* last change time */
-                               /* Times measured in secs since */
-                               /* 00:00:00 GMT, Jan. 1, 1970 */
-       long    sem_pad2;       /* SVABI/386 says I need this here */
-       long    sem_pad3[4];    /* SVABI/386 says I need this here */
-};

 
 

-/*
- * semop's sops parameter structure
- */
-struct sembuf {
-       u_short sem_num;        /* semaphore # */
-       short   sem_op;         /* semaphore operation */
-       short   sem_flg;        /* operation flags */
-};
-#define SEM_UNDO       010000
-
-#define MAX_SOPS       5       /* maximum # of sembuf's per semop call */
-
-/*
- * semctl's arg parameter structure
- */
-union semun {
-       int     val;            /* value for SETVAL */
-       struct  semid_ds *buf;  /* buffer for IPC_STAT & IPC_SET */
-       u_short *array;         /* array for GETALL & SETALL */
-};
-
-/*
- * commands for semctl
- */
-#define GETNCNT        3       /* Return the value of semncnt {READ} */
-#define GETPID 4       /* Return the value of sempid {READ} */
-#define GETVAL 5       /* Return the value of semval {READ} */
-#define GETALL 6       /* Return semvals into arg.array {READ} */
-#define GETZCNT        7       /* Return the value of semzcnt {READ} */
-#define SETVAL 8       /* Set the value of semval to arg.val {ALTER} */
-#define SETALL 9       /* Set semvals from arg.array {ALTER} */
+#include <sys/cdefs.h>
+#include <sys/_types.h>

 
 /*
 
 /*

- * Permissions
+ * [XSI]       All of the symbols from <sys/ipc.h> SHALL be defined
+ *             when this header is included

  */
  */

-#define SEM_A          0200    /* alter permission */
-#define SEM_R          0400    /* read permission */
+#include <sys/ipc.h>

 
 

-#ifdef KERNEL
-#ifdef __APPLE_API_PRIVATE
-/*
- * Kernel implementation stuff
- */
-#define SEMVMX 32767           /* semaphore maximum value */
-#define SEMAEM 16384           /* adjust on exit max value */

 
 /*
 
 /*

- * Configuration parameters.  SEMMNI, SEMMNS, and SEMMNU are hard limits.
- * The code dynamically allocates enough memory to satisfy the current
- * demand in even increments of SEMMNI_INC, SEMMNS_INC, and SEMMNU_INC.
- * The code will never allocate more than the hard limits.  The *_INC's
- * are defined in the kernel section of the header.
- */
-/*
- * Configuration parameters
+ * [XSI] The pid_t, time_t, key_t, and size_t types shall be defined as
+ * described in <sys/types.h>.
+ *
+ * NOTE:       The definition of the key_t type is implicit from the
+ *             inclusion of <sys/ipc.h>

  */
  */

-#ifndef SEMMNS                 /* # of semaphores in system */
-#define SEMMNS (1048576/sizeof(struct sem))
-#endif                         /* no more than 1M of semaphore data */
-#ifndef SEMMNI                 /* # of semaphore identifiers */
-#define SEMMNI SEMMNS          /* max of 1 for each semaphore */
-#endif
-#ifndef SEMUME
-#define SEMUME 10              /* max # of undo entries per process */
+#ifndef _PID_T
+typedef __darwin_pid_t pid_t;
+#define _PID_T

 #endif
 #endif

-#ifndef SEMMNU                 /* # of undo structures in system */
-#define SEMMNU SEMMNS          /* 1 for each semaphore.  This is quite large */
-#endif                         /* This should be max 1 for each process */

 
 

-/* shouldn't need tuning */
-#ifndef SEMMAP
-#define SEMMAP 30              /* # of entries in semaphore map */
-#endif
-#ifndef SEMMSL
-#define SEMMSL SEMMNS          /* max # of semaphores per id */
-#endif
-#ifndef SEMOPM
-#define SEMOPM 100             /* max # of operations per semop call */
+#ifndef        _TIME_T
+#define        _TIME_T
+typedef        __darwin_time_t time_t;

 #endif
 
 #endif
 

+#ifndef _SIZE_T
+#define _SIZE_T
+typedef __darwin_size_t        size_t;
+#endif

 
 /*
 
 /*

- * Undo structure (one per process)
+ * Technically, we should force all code references to the new structure
+ * definition, not in just the standards conformance case, and leave the
+ * legacy interface there for binary compatibility only.  Currently, we
+ * are only forcing this for programs requesting standards conformance.

  */
  */

-struct sem_undo {
-       struct  sem_undo *un_next;      /* ptr to next active undo structure */
-       struct  proc *un_proc;          /* owner of this structure */
-       short   un_cnt;                 /* # of active entries */
-       struct undo {
-               short   un_adjval;      /* adjust on exit values */
-               short   un_num;         /* semaphore # */
-               int     un_id;          /* semid */
-       } un_ent[SEMUME];               /* undo entries */
+#if __DARWIN_UNIX03 || defined(KERNEL)
+#pragma pack(4)
+/*
+ * Structure used internally.
+ * 
+ * This structure is exposed because standards dictate that it is used as
+ * the semun union member 'buf' as the fourth argment to semctl() when the
+ * third argument is IPC_STAT or IPC_SET.
+ *
+ * Note: only the fields sem_perm, sem_nsems, sem_otime, and sem_ctime
+ * are meaningful in user space.
+ */
+#if (defined(_POSIX_C_SOURCE) && !defined(_DARWIN_C_SOURCE))
+struct semid_ds
+#else
+#define        semid_ds        __semid_ds_new
+struct __semid_ds_new
+#endif
+{
+       struct __ipc_perm_new sem_perm; /* [XSI] operation permission struct */
+       __int32_t       sem_base;       /* 32 bit base ptr for semaphore set */
+       unsigned short  sem_nsems;      /* [XSI] number of sems in set */
+       time_t          sem_otime;      /* [XSI] last operation time */
+       __int32_t       sem_pad1;       /* RESERVED: DO NOT USE! */
+       time_t          sem_ctime;      /* [XSI] last change time */
+                                       /* Times measured in secs since */
+                                       /* 00:00:00 GMT, Jan. 1, 1970 */
+       __int32_t       sem_pad2;       /* RESERVED: DO NOT USE! */
+       __int32_t       sem_pad3[4];    /* RESERVED: DO NOT USE! */

 };
 };

+#pragma pack()
+#else  /* !__DARWIN_UNIX03 */
+#define        semid_ds        __semid_ds_old
+#endif /* __DARWIN_UNIX03 */
+
+#if !__DARWIN_UNIX03
+struct __semid_ds_old {
+       struct __ipc_perm_old sem_perm; /* [XSI] operation permission struct */
+       __int32_t       sem_base;       /* 32 bit base ptr for semaphore set */
+       unsigned short  sem_nsems;      /* [XSI] number of sems in set */
+       time_t          sem_otime;      /* [XSI] last operation time */
+       __int32_t       sem_pad1;       /* RESERVED: DO NOT USE! */
+       time_t          sem_ctime;      /* [XSI] last change time */
+                                       /* Times measured in secs since */
+                                       /* 00:00:00 GMT, Jan. 1, 1970 */
+       __int32_t       sem_pad2;       /* RESERVED: DO NOT USE! */
+       __int32_t       sem_pad3[4];    /* RESERVED: DO NOT USE! */
+};
+#endif /* !__DARWIN_UNIX03 */

 
 /*
 
 /*

- * semaphore info struct
+ * Possible values for the third argument to semctl()

  */
  */

-struct seminfo {
-       int     semmap,         /* # of entries in semaphore map */
-               semmni,         /* # of semaphore identifiers */
-               semmns,         /* # of semaphores in system */
-               semmnu,         /* # of undo structures in system */
-               semmsl,         /* max # of semaphores per id */
-               semopm,         /* max # of operations per semop call */
-               semume,         /* max # of undo entries per process */
-               semusz,         /* size in bytes of undo structure */
-               semvmx,         /* semaphore maximum value */
-               semaem;         /* adjust on exit max value */
-};
-extern struct seminfo  seminfo;
+#define GETNCNT        3       /* [XSI] Return the value of semncnt {READ} */
+#define GETPID 4       /* [XSI] Return the value of sempid {READ} */
+#define GETVAL 5       /* [XSI] Return the value of semval {READ} */
+#define GETALL 6       /* [XSI] Return semvals into arg.array {READ} */
+#define GETZCNT        7       /* [XSI] Return the value of semzcnt {READ} */
+#define SETVAL 8       /* [XSI] Set the value of semval to arg.val {ALTER} */
+#define SETALL 9       /* [XSI] Set semvals from arg.array {ALTER} */

 
 

-/* internal "mode" bits */
-#define        SEM_ALLOC       01000   /* semaphore is allocated */
-#define        SEM_DEST        02000   /* semaphore will be destroyed on last detach */

 
 

-#define SEMMNI_INC     8       /* increment value for semaphore identifiers */
-#define SEMMNS_INC     64      /* increment value for semaphores */
-#define SEMMNU_INC     32      /* increment value for undo structures */
+/* A semaphore; this is an anonymous structure, not for external use */
+struct sem {
+       unsigned short  semval;         /* semaphore value */
+       pid_t           sempid;         /* pid of last operation */
+       unsigned short  semncnt;        /* # awaiting semval > cval */
+       unsigned short  semzcnt;        /* # awaiting semval == 0 */
+};
+

 
 /*
 
 /*

- * Due to the way semaphore memory is allocated, we have to ensure that
- * SEMUSZ is properly aligned.
- *
- * We are not doing strange semaphore memory allocation anymore, so
- * these macros are no longer needed.
+ * Structure of array element for second argument to semop()

  */
  */

+struct sembuf {
+       unsigned short  sem_num;        /* [XSI] semaphore # */
+       short           sem_op;         /* [XSI] semaphore operation */
+       short           sem_flg;        /* [XSI] operation flags */
+};

 
 /*
 
 /*

- * #define SEM_ALIGN(bytes) (((bytes) + (sizeof(long) - 1)) & ~(sizeof(long) - 1))
+ * Possible flag values for sem_flg

  */
  */

+#define SEM_UNDO       010000          /* [XSI] Set up adjust on exit entry */
+
+
+#if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)

 
 

-/* actual size of an undo structure */

 /*
 /*

- * #define SEMUSZ      SEM_ALIGN(offsetof(struct sem_undo, un_ent[SEMUME]))
+ * System imposed limit on the value of the third parameter to semop().
+ * This is arbitrary, and the standards unfortunately do not provide a
+ * way for user applications to retrieve this value (e.g. via sysconf()
+ * or from a manifest value in <unistd.h>).  The value shown here is
+ * informational, and subject to change in future revisions.

  */
  */

-#define SEMUSZ         sizeof(struct sem_undo)
+#define MAX_SOPS       5       /* maximum # of sembuf's per semop call */

 
 

-extern struct semid_ds *sema;  /* semaphore id pool */
-extern struct sem *sem;                /* semaphore pool */
-/* This is now a struct sem_undo with the new memory allocation 
- * extern int  *semu;          /* undo structure pool
- */
-extern struct sem_undo *semu;          /* undo structure pool */

 
 /*
 
 /*

- * Macro to find a particular sem_undo vector
- */
-/* Until we can initialize seminfo.semusz to SEMUSZ, we hard code the size macro
- * in SEMU.  This should be fixed when (if) we implement dynamic pool sizes
+ * Union used as the fourth argment to semctl() in all cases.  Specific
+ * member values are used for different values of the third parameter:
+ * 
+ * Command                                     Member
+ * ------------------------------------------- ------
+ * GETALL, SETALL                              array
+ * SETVAL                                      val
+ * IPC_STAT, IPC_SET                           buf

  *
  *

- * #define SEMU(ix)     ((struct sem_undo *)(((intptr_t)semu)+ix * seminfo.semusz))
- */
-/*
- * This macro doesn't work because we are using a staticly allocated array
- * for semu now.
- * #define SEMU(ix)        ((struct sem_undo *)(((intptr_t)semu)+ix * SEMUSZ)) 
+ * The union definition is intended to be defined by the user application
+ * in conforming applications; it is provided here for two reasons:
+ * 
+ * 1)  Historical source compatability for non-conforming applications
+ *     expecting this header to declare the union type on their behalf
+ *
+ * 2)  Documentation; specifically, 64 bit applications that do not pass
+ *     this structure for 'val', or, alternately, a 64 bit type, will
+ *     not function correctly

  */
  */

-#define SEMU(ix)        (&semu[ix])
+union semun {
+       int             val;            /* value for SETVAL */
+       struct semid_ds *buf;           /* buffer for IPC_STAT & IPC_SET */
+       unsigned short  *array;         /* array for GETALL & SETALL */
+};
+typedef union semun semun_t;

 
 
 /*
 
 
 /*

- * Process sem_undo vectors at proc exit.
+ * Permissions

  */
  */

-void   semexit __P((struct proc *p));
+#define SEM_A          0200    /* alter permission */
+#define SEM_R          0400    /* read permission */

 
 

-/*
- * Parameters to the semconfig system call
- */
-typedef enum {
-       SEM_CONFIG_FREEZE,      /* Freeze the semaphore facility. */
-       SEM_CONFIG_THAW         /* Thaw the semaphore facility. */
-} semconfig_ctl_t;
+#endif /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */

 
 

-#endif /* __APPLE_API_PRIVATE */

 
 

-#endif /* KERNEL */

 
 #ifndef KERNEL
 
 #ifndef KERNEL

-#include <sys/cdefs.h>

 
 __BEGIN_DECLS
 
 __BEGIN_DECLS

-int semsys __P((int, ...));
-int semctl __P((int, int, int, union semun));
-int semget __P((key_t, int, int));
-int semop __P((int, struct sembuf *,unsigned));
+#if !defined(_POSIX_C_SOURCE) || defined(_DARWIN_C_SOURCE)
+int    semsys(int, ...);
+#endif /* (!_POSIX_C_SOURCE || _DARWIN_C_SOURCE) */
+int    semctl(int, int, int, ...) __DARWIN_ALIAS(semctl);
+int    semget(key_t, int, int);
+int    semop(int, struct sembuf *, size_t);

 __END_DECLS
 __END_DECLS

+

 #endif /* !KERNEL */
 
 #endif /* !_SEM_H_ */
 #endif /* !KERNEL */
 
 #endif /* !_SEM_H_ */