prio.h

Netscape NSPR库源码

typedef PRInt32 (PR_CALLBACK *PRRecvFN)(
    PRFileDesc *fd, void *buf, PRInt32 amount,
    PRIntn flags, PRIntervalTime timeout);
typedef PRInt32 (PR_CALLBACK *PRSendFN) (
    PRFileDesc *fd, const void *buf, PRInt32 amount,
    PRIntn flags, PRIntervalTime timeout);
typedef PRInt32 (PR_CALLBACK *PRRecvfromFN)(
    PRFileDesc *fd, void *buf, PRInt32 amount,
    PRIntn flags, PRNetAddr *addr, PRIntervalTime timeout);
typedef PRInt32 (PR_CALLBACK *PRSendtoFN)(
    PRFileDesc *fd, const void *buf, PRInt32 amount,
    PRIntn flags, const PRNetAddr *addr, PRIntervalTime timeout);
typedef PRInt16 (PR_CALLBACK *PRPollFN)(
    PRFileDesc *fd, PRInt16 in_flags, PRInt16 *out_flags);
typedef PRInt32 (PR_CALLBACK *PRAcceptreadFN)(
    PRFileDesc *sd, PRFileDesc **nd, PRNetAddr **raddr,
    void *buf, PRInt32 amount, PRIntervalTime t);
typedef PRInt32 (PR_CALLBACK *PRTransmitfileFN)(
     PRFileDesc *sd, PRFileDesc *fd, const void *headers,
     PRInt32 hlen, PRTransmitFileFlags flags, PRIntervalTime t);
typedef PRStatus (PR_CALLBACK *PRGetsocknameFN)(PRFileDesc *fd, PRNetAddr *addr);
typedef PRStatus (PR_CALLBACK *PRGetpeernameFN)(PRFileDesc *fd, PRNetAddr *addr);
typedef PRStatus (PR_CALLBACK *PRGetsocketoptionFN)(
    PRFileDesc *fd, PRSocketOptionData *data);
typedef PRStatus (PR_CALLBACK *PRSetsocketoptionFN)(
    PRFileDesc *fd, const PRSocketOptionData *data);
typedef PRInt32 (PR_CALLBACK *PRSendfileFN)(
	PRFileDesc *networkSocket, PRSendFileData *sendData,
	PRTransmitFileFlags flags, PRIntervalTime timeout);
typedef PRStatus (PR_CALLBACK *PRConnectcontinueFN)(
    PRFileDesc *fd, PRInt16 out_flags);
typedef PRIntn (PR_CALLBACK *PRReservedFN)(PRFileDesc *fd);

struct PRIOMethods {
    PRDescType file_type;           /* Type of file represented (tos)           */
    PRCloseFN close;                /* close file and destroy descriptor        */
    PRReadFN read;                  /* read up to specified bytes into buffer   */
    PRWriteFN write;                /* write specified bytes from buffer        */
    PRAvailableFN available;        /* determine number of bytes available      */
    PRAvailable64FN available64;    /*          ditto, 64 bit                   */
    PRFsyncFN fsync;                /* flush all buffers to permanent store     */
    PRSeekFN seek;                  /* position the file to the desired place   */
    PRSeek64FN seek64;              /*           ditto, 64 bit                  */
    PRFileInfoFN fileInfo;          /* Get information about an open file       */
    PRFileInfo64FN fileInfo64;      /*           ditto, 64 bit                  */
    PRWritevFN writev;              /* Write segments as described by iovector  */
    PRConnectFN connect;            /* Connect to the specified (net) address   */
    PRAcceptFN accept;              /* Accept a connection for a (net) peer     */
    PRBindFN bind;                  /* Associate a (net) address with the fd    */
    PRListenFN listen;              /* Prepare to listen for (net) connections  */
    PRShutdownFN shutdown;          /* Shutdown a (net) connection              */
    PRRecvFN recv;                  /* Solicit up the the specified bytes       */
    PRSendFN send;                  /* Send all the bytes specified             */
    PRRecvfromFN recvfrom;          /* Solicit (net) bytes and report source    */
    PRSendtoFN sendto;              /* Send bytes to (net) address specified    */
    PRPollFN poll;                  /* Test the fd to see if it is ready        */
    PRAcceptreadFN acceptread;      /* Accept and read on a new (net) fd        */
    PRTransmitfileFN transmitfile;  /* Transmit at entire file                  */
    PRGetsocknameFN getsockname;    /* Get (net) address associated with fd     */
    PRGetpeernameFN getpeername;    /* Get peer's (net) address                 */
    PRReservedFN reserved_fn_6;     /* reserved for future use */
    PRReservedFN reserved_fn_5;     /* reserved for future use */
    PRGetsocketoptionFN getsocketoption;
                                    /* Get current setting of specified option  */
    PRSetsocketoptionFN setsocketoption;
                                    /* Set value of specified option            */
    PRSendfileFN sendfile;			/* Send a (partial) file with header/trailer*/
    PRConnectcontinueFN connectcontinue;
                                    /* Continue a nonblocking connect */
    PRReservedFN reserved_fn_3;		/* reserved for future use */
    PRReservedFN reserved_fn_2;		/* reserved for future use */
    PRReservedFN reserved_fn_1;		/* reserved for future use */
    PRReservedFN reserved_fn_0;		/* reserved for future use */
};

/*
 **************************************************************************
 * FUNCTION: PR_GetSpecialFD
 * DESCRIPTION: Get the file descriptor that represents the standard input,
 *              output, or error stream.
 * INPUTS:
 *     PRSpecialFD id
 *         A value indicating the type of stream desired:
 *             PR_StandardInput: standard input
 *             PR_StandardOuput: standard output
 *             PR_StandardError: standard error
 * OUTPUTS: none
 * RETURNS: PRFileDesc *
 *     If the argument is valid, PR_GetSpecialFD returns a file descriptor
 *     that represents the corresponding standard I/O stream.  Otherwise,
 *     PR_GetSpecialFD returns NULL and sets error PR_INVALID_ARGUMENT_ERROR.
 **************************************************************************
 */

typedef enum PRSpecialFD
{
    PR_StandardInput,          /* standard input */
    PR_StandardOutput,         /* standard output */
    PR_StandardError           /* standard error */
} PRSpecialFD;

NSPR_API(PRFileDesc*) PR_GetSpecialFD(PRSpecialFD id);

#define PR_STDIN	PR_GetSpecialFD(PR_StandardInput)
#define PR_STDOUT	PR_GetSpecialFD(PR_StandardOutput)
#define PR_STDERR	PR_GetSpecialFD(PR_StandardError)

/*
 **************************************************************************
 * Layering file descriptors
 *
 * File descriptors may be layered. Each layer has it's own identity.
 * Identities are allocated by the runtime and are to be associated
 * (by the layer implementor) with all layers that are of that type.
 * It is then possible to scan the chain of layers and find a layer
 * that one recongizes and therefore predict that it will implement
 * a desired protocol.
 *
 * There are three well-known identities:
 *      PR_INVALID_IO_LAYER => an invalid layer identity, for error return
 *      PR_TOP_IO_LAYER     => the identity of the top of the stack
 *      PR_NSPR_IO_LAYER    => the identity used by NSPR proper
 * PR_TOP_IO_LAYER may be used as a shorthand for identifying the topmost
 * layer of an existing stack. Ie., the following two constructs are
 * equivalent.
 *
 *      rv = PR_PushIOLayer(stack, PR_TOP_IO_LAYER, my_layer);
 *      rv = PR_PushIOLayer(stack, PR_GetLayersIdentity(stack), my_layer)
 *
 * A string may be associated with the creation of the identity. It
 * will be copied by the runtime. If queried the runtime will return
 * a reference to that copied string (not yet another copy). There
 * is no facility for deleting an identity.
 **************************************************************************
 */

#define PR_IO_LAYER_HEAD (PRDescIdentity)-3
#define PR_INVALID_IO_LAYER (PRDescIdentity)-1
#define PR_TOP_IO_LAYER (PRDescIdentity)-2
#define PR_NSPR_IO_LAYER (PRDescIdentity)0

NSPR_API(PRDescIdentity) PR_GetUniqueIdentity(const char *layer_name);
NSPR_API(const char*) PR_GetNameForIdentity(PRDescIdentity ident);
NSPR_API(PRDescIdentity) PR_GetLayersIdentity(PRFileDesc* fd);
NSPR_API(PRFileDesc*) PR_GetIdentitiesLayer(PRFileDesc* fd_stack, PRDescIdentity id);

/*
 **************************************************************************
 * PR_GetDefaultIOMethods: Accessing the default methods table.
 * You may get a pointer to the default methods table by calling this function.
 * You may then select any elements from that table with which to build your
 * layer's methods table. You may NOT modify the table directly.
 **************************************************************************
 */
NSPR_API(const PRIOMethods *) PR_GetDefaultIOMethods(void);

/*
 **************************************************************************
 * Creating a layer
 *
 * A new layer may be allocated by calling PR_CreateIOLayerStub(). The
 * file descriptor returned will contain the pointer to the methods table
 * provided. The runtime will not modify the table nor test its correctness.
 **************************************************************************
 */
NSPR_API(PRFileDesc*) PR_CreateIOLayerStub(
    PRDescIdentity ident, const PRIOMethods *methods);

/*
 **************************************************************************
 * Creating a layer
 *
 * A new stack may be created by calling PR_CreateIOLayer(). The
 * file descriptor returned will point to the top of the stack, which has
 * the layer 'fd' as the topmost layer.
 * 
 * NOTE: This function creates a new style stack, which has a fixed, dummy
 * header. The old style stack, created by a call to PR_PushIOLayer,
 * results in modifying contents of the top layer of the stack, when
 * pushing and popping layers of the stack.
 **************************************************************************
 */
NSPR_API(PRFileDesc*) PR_CreateIOLayer(PRFileDesc* fd);

/*
 **************************************************************************
 * Pushing a layer
 *
 * A file descriptor (perhaps allocated using PR_CreateIOLayerStub()) may
 * be pushed into an existing stack of file descriptors at any point the
 * caller deems appropriate. The new layer will be inserted into the stack
 * just above the layer with the indicated identity.
 *
 * Note: Even if the identity parameter indicates the top-most layer of
 * the stack, the value of the file descriptor describing the original
 * stack will not change.
 **************************************************************************
 */
NSPR_API(PRStatus) PR_PushIOLayer(
    PRFileDesc *fd_stack, PRDescIdentity id, PRFileDesc *layer);

/*
 **************************************************************************
 * Popping a layer
 *
 * A layer may be popped from a stack by indicating the identity of the
 * layer to be removed. If found, a pointer to the removed object will
 * be returned to the caller. The object then becomes the responsibility
 * of the caller.
 *
 * Note: Even if the identity indicates the top layer of the stack, the
 * reference returned will not be the file descriptor for the stack and
 * that file descriptor will remain valid.
 **************************************************************************
 */
NSPR_API(PRFileDesc*) PR_PopIOLayer(PRFileDesc *fd_stack, PRDescIdentity id);

/*
 **************************************************************************
 * FUNCTION:    PR_Open
 * DESCRIPTION:    Open a file for reading, writing, or both.
 * INPUTS:
 *     const char *name
 *         The path name of the file to be opened
 *     PRIntn flags
 *         The file status flags.
 *         It is a bitwise OR of the following bit flags (only one of
 *         the first three flags below may be used):
 *		PR_RDONLY        Open for reading only.
 *		PR_WRONLY        Open for writing only.
 *		PR_RDWR          Open for reading and writing.
 *		PR_CREATE_FILE   If the file does not exist, the file is created
 *                              If the file exists, this flag has no effect.
 *      PR_SYNC          If set, each write will wait for both the file data
 *                              and file status to be physically updated.
 *		PR_APPEND        The file pointer is set to the end of
 *                              the file prior to each write.
 *		PR_TRUNCATE      If the file exists, its length is truncated to 0.
 *      PR_EXCL          With PR_CREATE_FILE, if the file does not exist,
 *                              the file is created. If the file already 
 *                              exists, no action and NULL is returned
 *
 *     PRIntn mode
 *         The access permission bits of the file mode, if the file is
 *         created when PR_CREATE_FILE is on.
 * OUTPUTS:    None
 * RETURNS:    PRFileDesc *
 *     If the file is successfully opened,
 *     returns a pointer to the PRFileDesc
 *     created for the newly opened file.
 *     Returns a NULL pointer if the open
 *     failed.
 * SIDE EFFECTS:
 * RESTRICTIONS:
 * MEMORY:
 *     The return value, if not NULL, points to a dynamically allocated
 *     PRFileDesc object.
 * ALGORITHM:
 **************************************************************************
 */

/* Open flags */
#define PR_RDONLY       0x01
#define PR_WRONLY       0x02
#define PR_RDWR         0x04
#define PR_CREATE_FILE  0x08
#define PR_APPEND       0x10
#define PR_TRUNCATE     0x20
#define PR_SYNC         0x40
#define PR_EXCL         0x80

/*
** File modes ....
**
** CAVEAT: 'mode' is currently only applicable on UNIX platforms.
** The 'mode' argument may be ignored by PR_Open on other platforms.
**
**   00400   Read by owner.
**   00200   Write by owner.
**   00100   Execute (search if a directory) by owner.
**   00040   Read by group.
**   00020   Write by group.
**   00010   Execute by group.
**   00004   Read by others.
**   00002   Write by others
**   00001   Execute by others.
**
*/

NSPR_API(PRFileDesc*) PR_Open(const char *name, PRIntn flags, PRIntn mode);

/*
 **************************************************************************
 * FUNCTION: PR_OpenFile
 * DESCRIPTION:
 *     Open a file for reading, writing, or both.
 *     PR_OpenFile has the same prototype as PR_Open but implements
 *     the specified file mode where possible.
 **************************************************************************
 */

/* File mode bits */
#define PR_IRWXU 00700  /* read, write, execute/search by owner */
#define PR_IRUSR 00400  /* read permission, owner */
#define PR_IWUSR 00200  /* write permission, owner */
#define PR_IXUSR 00100  /* execute/search permission, owner */
#define PR_IRWXG 00070  /* read, write, execute/search by group */
#define PR_IRGRP 00040  /* read permission, group */
#define PR_IWGRP 00020  /* write permission, group */
#define PR_IXGRP 00010  /* execute/search permission, group */
#define PR_IRWXO 00007  /* read, write, execute/search by others */
#define PR_IROTH 00004  /* read permission, others */
#define PR_IWOTH 00002  /* write permission, others */
#define PR_IXOTH 00001  /* execute/search permission, others */

NSPR_API(PRFileDesc*) PR_OpenFile(
    const char *name, PRIntn flags, PRIntn mode);

/*
 **************************************************************************
 * FUNCTION: PR_Close
 * DESCRIPTION:
 *     Close a file or socket.
 * INPUTS:
 *     PRFileDesc *fd
 *         a pointer to a PRFileDesc.
 * OUTPUTS:
 *     None.
 * RETURN:
 *     PRStatus
 * SIDE EFFECTS:
 * RESTRICTIONS:
 *     None.
 * MEMORY: