| Index: mozilla/nsprpub/pr/include/prshma.h
|
| ===================================================================
|
| --- mozilla/nsprpub/pr/include/prshma.h (revision 191424)
|
| +++ mozilla/nsprpub/pr/include/prshma.h (working copy)
|
| @@ -1,239 +0,0 @@
|
| -/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
| -/* This Source Code Form is subject to the terms of the Mozilla Public
|
| - * License, v. 2.0. If a copy of the MPL was not distributed with this
|
| - * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
| -
|
| -/*
|
| -** prshma.h -- NSPR Anonymous Shared Memory
|
| -**
|
| -** NSPR provides an anonymous shared memory based on NSPR's PRFileMap
|
| -** type. The anonymous file-mapped shared memory provides an inheritable
|
| -** shared memory, as in: the child process inherits the shared memory.
|
| -** Compare the file-mapped anonymous shared memory to to a named shared
|
| -** memory described in prshm.h. The intent is to provide a shared
|
| -** memory that is accessable only by parent and child processes. ...
|
| -** It's a security thing.
|
| -**
|
| -** Depending on the underlying platform, the file-mapped shared memory
|
| -** may be backed by a file. ... surprise! ... On some platforms, no
|
| -** real file backs the shared memory. On platforms where the shared
|
| -** memory is backed by a file, the file's name in the filesystem is
|
| -** visible to other processes for only the duration of the creation of
|
| -** the file, hopefully a very short time. This restricts processess
|
| -** that do not inherit the shared memory from opening the file and
|
| -** reading or writing its contents. Further, when all processes
|
| -** using an anonymous shared memory terminate, the backing file is
|
| -** deleted. ... If you are not paranoid, you're not paying attention.
|
| -**
|
| -** The file-mapped shared memory requires a protocol for the parent
|
| -** process and child process to share the memory. NSPR provides two
|
| -** protocols. Use one or the other; don't mix and match.
|
| -**
|
| -** In the first protocol, the job of passing the inheritable shared
|
| -** memory is done via helper-functions with PR_CreateProcess(). In the
|
| -** second protocol, the parent process is responsible for creating the
|
| -** child process; the parent and child are mutually responsible for
|
| -** passing a FileMap string. NSPR provides helper functions for
|
| -** extracting data from the PRFileMap object. ... See the examples
|
| -** below.
|
| -**
|
| -** Both sides should adhere strictly to the protocol for proper
|
| -** operation. The pseudo-code below shows the use of a file-mapped
|
| -** shared memory by a parent and child processes. In the examples, the
|
| -** server creates the file-mapped shared memory, the client attaches to
|
| -** it.
|
| -**
|
| -** First protocol.
|
| -** Server:
|
| -**
|
| -** fm = PR_OpenAnonFileMap(dirName, size, FilemapProt);
|
| -** addr = PR_MemMap(fm);
|
| -** attr = PR_NewProcessAttr();
|
| -** PR_ProcessAttrSetInheritableFileMap( attr, fm, shmname );
|
| -** PR_CreateProcess(Client);
|
| -** PR_DestroyProcessAttr(attr);
|
| -** ... yadda ...
|
| -** PR_MemUnmap( addr );
|
| -** PR_CloseFileMap(fm);
|
| -**
|
| -**
|
| -** Client:
|
| -** ... started by server via PR_CreateProcess()
|
| -** fm = PR_GetInheritedFileMap( shmname );
|
| -** addr = PR_MemMap(fm);
|
| -** ... yadda ...
|
| -** PR_MemUnmap(addr);
|
| -** PR_CloseFileMap(fm);
|
| -**
|
| -**
|
| -** Second Protocol:
|
| -** Server:
|
| -**
|
| -** fm = PR_OpenAnonFileMap(dirName, size, FilemapProt);
|
| -** fmstring = PR_ExportFileMapAsString( fm );
|
| -** addr = PR_MemMap(fm);
|
| -** ... application specific technique to pass fmstring to child
|
| -** ... yadda ... Server uses his own magic to create child
|
| -** PR_MemUnmap( addr );
|
| -** PR_CloseFileMap(fm);
|
| -**
|
| -**
|
| -** Client:
|
| -** ... started by server via his own magic
|
| -** ... application specific technique to find fmstring from parent
|
| -** fm = PR_ImportFileMapFromString( fmstring )
|
| -** addr = PR_MemMap(fm);
|
| -** ... yadda ...
|
| -** PR_MemUnmap(addr);
|
| -** PR_CloseFileMap(fm);
|
| -**
|
| -**
|
| -** lth. 2-Jul-1999.
|
| -**
|
| -** Note: The second protocol was requested by NelsonB (7/1999); this is
|
| -** to accomodate servers which already create their own child processes
|
| -** using platform native methods.
|
| -**
|
| -*/
|
| -
|
| -#ifndef prshma_h___
|
| -#define prshma_h___
|
| -
|
| -#include "prtypes.h"
|
| -#include "prio.h"
|
| -#include "prproces.h"
|
| -
|
| -PR_BEGIN_EXTERN_C
|
| -
|
| -/*
|
| -** PR_OpenAnonFileMap() -- Creates an anonymous file-mapped shared memory
|
| -**
|
| -** Description:
|
| -** PR_OpenAnonFileMap() creates an anonymous shared memory. If the
|
| -** shared memory already exists, a handle is returned to that shared
|
| -** memory object.
|
| -**
|
| -** On Unix platforms, PR_OpenAnonFileMap() uses 'dirName' as a
|
| -** directory name, without the trailing '/', to contain the anonymous
|
| -** file. A filename is generated for the name.
|
| -**
|
| -** On Windows platforms, dirName is ignored.
|
| -**
|
| -** Inputs:
|
| -** dirName -- A directory name to contain the anonymous file.
|
| -** size -- The size of the shared memory
|
| -** prot -- How the shared memory is mapped. See prio.h
|
| -**
|
| -** Outputs:
|
| -** PRFileMap *
|
| -**
|
| -** Returns:
|
| -** Pointer to PRFileMap or NULL on error.
|
| -**
|
| -*/
|
| -NSPR_API( PRFileMap *)
|
| -PR_OpenAnonFileMap(
|
| - const char *dirName,
|
| - PRSize size,
|
| - PRFileMapProtect prot
|
| -);
|
| -
|
| -/*
|
| -** PR_ProcessAttrSetInheritableFileMap() -- Prepare FileMap for export
|
| -** to my children processes via PR_CreateProcess()
|
| -**
|
| -** Description:
|
| -** PR_ProcessAttrSetInheritableFileMap() connects the PRFileMap to
|
| -** PRProcessAttr with shmname. A subsequent call to PR_CreateProcess()
|
| -** makes the PRFileMap importable by the child process.
|
| -**
|
| -** Inputs:
|
| -** attr -- PRProcessAttr, used to pass data to PR_CreateProcess()
|
| -** fm -- PRFileMap structure to be passed to the child process
|
| -** shmname -- The name for the PRFileMap; used by child.
|
| -**
|
| -** Outputs:
|
| -** PRFileMap *
|
| -**
|
| -** Returns:
|
| -** PRStatus
|
| -**
|
| -*/
|
| -NSPR_API(PRStatus)
|
| -PR_ProcessAttrSetInheritableFileMap(
|
| - PRProcessAttr *attr,
|
| - PRFileMap *fm,
|
| - const char *shmname
|
| -);
|
| -
|
| -/*
|
| -** PR_GetInheritedFileMap() -- Import a PRFileMap previously exported
|
| -** by my parent process via PR_CreateProcess()
|
| -**
|
| -** Description:
|
| -** PR_GetInheritedFileMap() retrieves a PRFileMap object exported from
|
| -** its parent process via PR_CreateProcess().
|
| -**
|
| -** Inputs:
|
| -** shmname -- The name provided to PR_ProcessAttrSetInheritableFileMap()
|
| -**
|
| -** Outputs:
|
| -** PRFileMap *
|
| -**
|
| -** Returns:
|
| -** PRFileMap pointer or NULL.
|
| -**
|
| -*/
|
| -NSPR_API( PRFileMap *)
|
| -PR_GetInheritedFileMap(
|
| - const char *shmname
|
| -);
|
| -
|
| -/*
|
| -** PR_ExportFileMapAsString() -- Creates a string identifying a PRFileMap
|
| -**
|
| -** Description:
|
| -** Creates an identifier, as a string, from a PRFileMap object
|
| -** previously created with PR_OpenAnonFileMap().
|
| -**
|
| -** Inputs:
|
| -** fm -- PRFileMap pointer to be represented as a string.
|
| -** bufsize -- sizeof(buf)
|
| -** buf -- a buffer of length PR_FILEMAP_STRING_BUFSIZE
|
| -**
|
| -** Outputs:
|
| -** buf contains the stringized PRFileMap identifier
|
| -**
|
| -** Returns:
|
| -** PRStatus
|
| -**
|
| -*/
|
| -NSPR_API( PRStatus )
|
| -PR_ExportFileMapAsString(
|
| - PRFileMap *fm,
|
| - PRSize bufsize,
|
| - char *buf
|
| -);
|
| -#define PR_FILEMAP_STRING_BUFSIZE 128
|
| -
|
| -/*
|
| -** PR_ImportFileMapFromString() -- Creates a PRFileMap from the identifying string
|
| -**
|
| -** Description:
|
| -** PR_ImportFileMapFromString() creates a PRFileMap object from a
|
| -** string previously created by PR_ExportFileMapAsString().
|
| -**
|
| -** Inputs:
|
| -** fmstring -- string created by PR_ExportFileMapAsString()
|
| -**
|
| -** Returns:
|
| -** PRFileMap pointer or NULL.
|
| -**
|
| -*/
|
| -NSPR_API( PRFileMap * )
|
| -PR_ImportFileMapFromString(
|
| - const char *fmstring
|
| -);
|
| -
|
| -PR_END_EXTERN_C
|
| -#endif /* prshma_h___ */
|
|
|