ptio.c

Netscape NSPR库源码

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 
 * The contents of this file are subject to the Mozilla Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/MPL/
 * 
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 * 
 * The Original Code is the Netscape Portable Runtime (NSPR).
 * 
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are 
 * Copyright (C) 1998-2000 Netscape Communications Corporation.  All
 * Rights Reserved.
 * 
 * Contributor(s):
 * 
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License Version 2 or later (the
 * "GPL"), in which case the provisions of the GPL are applicable 
 * instead of those above.  If you wish to allow use of your 
 * version of this file only under the terms of the GPL and not to
 * allow others to use your version of this file under the MPL,
 * indicate your decision by deleting the provisions above and
 * replace them with the notice and other provisions required by
 * the GPL.  If you do not delete the provisions above, a recipient
 * may use your version of this file under either the MPL or the
 * GPL.
 */

/*
** File:   ptio.c
** Descritpion:  Implemenation of I/O methods for pthreads
*/

#if defined(_PR_PTHREADS)

#if defined(_PR_POLL_WITH_SELECT)
/* set fd limit for select(), before including system header files */
#define FD_SETSIZE (16 * 1024)
#endif

#include <pthread.h>
#include <string.h>  /* for memset() */
#include <sys/types.h>
#include <dirent.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#if defined(SOLARIS) || defined(UNIXWARE)
#include <sys/filio.h>  /* to pick up FIONREAD */
#endif
#ifdef _PR_POLL_AVAILABLE
#include <poll.h>
#endif
#ifdef AIX
/* To pick up sysconf() */
#include <unistd.h>
#include <dlfcn.h>  /* for dlopen */
#else
/* To pick up getrlimit() etc. */
#include <sys/time.h>
#include <sys/resource.h>
#endif

#ifdef SOLARIS
/*
 * Define HAVE_SENDFILEV if the system has the sendfilev() system call.
 * Code built this way won't run on a system without sendfilev().
 * We can define HAVE_SENDFILEV by default when the minimum release
 * of Solaris that NSPR supports has sendfilev().
 */
#ifdef HAVE_SENDFILEV

#include <sys/sendfile.h>

#define SOLARIS_SENDFILEV(a, b, c, d) sendfilev((a), (b), (c), (d))

#else

#include <dlfcn.h>  /* for dlopen */

/*
 * Match the definitions in <sys/sendfile.h>.
 */
typedef struct sendfilevec {
    int sfv_fd;       /* input fd */
    uint_t sfv_flag;  /* flags */
    off_t sfv_off;    /* offset to start reading from */
    size_t sfv_len;   /* amount of data */
} sendfilevec_t;

#define SFV_FD_SELF (-2)

/*
 * extern ssize_t sendfilev(int, const struct sendfilevec *, int, size_t *);
 */
static ssize_t (*pt_solaris_sendfilev_fptr)() = NULL;

#define SOLARIS_SENDFILEV(a, b, c, d) \
        (*pt_solaris_sendfilev_fptr)((a), (b), (c), (d))

#endif /* HAVE_SENDFILEV */
#endif /* SOLARIS */

/*
 * The send_file() system call is available in AIX 4.3.2 or later.
 * If this file is compiled on an older AIX system, it attempts to
 * look up the send_file symbol at run time to determine whether
 * we can use the faster PR_SendFile/PR_TransmitFile implementation based on
 * send_file().  On AIX 4.3.2 or later, we can safely skip this
 * runtime function dispatching and just use the send_file based
 * implementation.
 */
#ifdef AIX
#ifdef SF_CLOSE
#define HAVE_SEND_FILE
#endif

#ifdef HAVE_SEND_FILE

#define AIX_SEND_FILE(a, b, c) send_file(a, b, c)

#else /* HAVE_SEND_FILE */

/*
 * The following definitions match those in <sys/socket.h>
 * on AIX 4.3.2.
 */

/*
 * Structure for the send_file() system call
 */
struct sf_parms {
    /* --------- header parms ---------- */
    void      *header_data;         /* Input/Output. Points to header buf */
    uint_t    header_length;        /* Input/Output. Length of the header */
    /* --------- file parms ------------ */
    int       file_descriptor;      /* Input. File descriptor of the file */
    unsigned long long file_size;   /* Output. Size of the file */
    unsigned long long file_offset; /* Input/Output. Starting offset */
    long long file_bytes;           /* Input/Output. no. of bytes to send */
    /* --------- trailer parms --------- */
    void      *trailer_data;        /* Input/Output. Points to trailer buf */
    uint_t    trailer_length;       /* Input/Output. Length of the trailer */
    /* --------- return info ----------- */
    unsigned long long bytes_sent;  /* Output. no. of bytes sent */
};

/*
 * Flags for the send_file() system call
 */
#define SF_CLOSE        0x00000001      /* close the socket after completion */
#define SF_REUSE        0x00000002      /* reuse socket. not supported */
#define SF_DONT_CACHE   0x00000004      /* don't apply network buffer cache */
#define SF_SYNC_CACHE   0x00000008      /* sync/update network buffer cache */

/*
 * prototype: size_t send_file(int *, struct sf_parms *, uint_t);
 */
static ssize_t (*pt_aix_sendfile_fptr)() = NULL;

#define AIX_SEND_FILE(a, b, c) (*pt_aix_sendfile_fptr)(a, b, c)

#endif /* HAVE_SEND_FILE */
#endif /* AIX */

#ifdef LINUX
#include <sys/sendfile.h>
#endif

#include "primpl.h"

#include <netinet/tcp.h>  /* TCP_NODELAY, TCP_MAXSEG */
#ifdef LINUX
/* TCP_CORK is not defined in <netinet/tcp.h> on Red Hat Linux 6.0 */
#ifndef TCP_CORK
#define TCP_CORK 3
#endif
#endif

#if defined(SOLARIS)
#define _PRSockOptVal_t char *
#elif defined(IRIX) || defined(OSF1) || defined(AIX) || defined(HPUX) \
    || defined(LINUX) || defined(FREEBSD) || defined(BSDI) || defined(VMS) \
    || defined(NTO) || defined(OPENBSD) || defined(DARWIN) \
    || defined(UNIXWARE)
#define _PRSockOptVal_t void *
#else
#error "Cannot determine architecture"
#endif

#if (defined(HPUX) && !defined(HPUX10_30) && !defined(HPUX11))
#define _PRSelectFdSetArg_t int *
#elif defined(AIX4_1)
#define _PRSelectFdSetArg_t void *
#elif defined(IRIX) || (defined(AIX) && !defined(AIX4_1)) \
    || defined(OSF1) || defined(SOLARIS) \
    || defined(HPUX10_30) || defined(HPUX11) || defined(LINUX) \
    || defined(FREEBSD) || defined(NETBSD) || defined(OPENBSD) \
    || defined(BSDI) || defined(VMS) || defined(NTO) || defined(DARWIN) \
    || defined(UNIXWARE)
#define _PRSelectFdSetArg_t fd_set *
#else
#error "Cannot determine architecture"
#endif

static PRFileDesc *pt_SetMethods(
    PRIntn osfd, PRDescType type, PRBool isAcceptedSocket, PRBool imported);

static PRLock *_pr_flock_lock;  /* For PR_LockFile() etc. */
static PRCondVar *_pr_flock_cv;  /* For PR_LockFile() etc. */
static PRLock *_pr_rename_lock;  /* For PR_Rename() */

/**************************************************************************/

/* These two functions are only used in assertions. */
#if defined(DEBUG)

PRBool IsValidNetAddr(const PRNetAddr *addr)
{
    if ((addr != NULL)
            && (addr->raw.family != AF_UNIX)
            && (addr->raw.family != PR_AF_INET6)
            && (addr->raw.family != AF_INET)) {
        return PR_FALSE;
    }
    return PR_TRUE;
}

static PRBool IsValidNetAddrLen(const PRNetAddr *addr, PRInt32 addr_len)
{
    /*
     * The definition of the length of a Unix domain socket address
     * is not uniform, so we don't check it.
     */
    if ((addr != NULL)
            && (addr->raw.family != AF_UNIX)
            && (PR_NETADDR_SIZE(addr) != addr_len)) {
#if defined(LINUX) && __GLIBC__ == 2 && __GLIBC_MINOR__ == 1
        /*
         * In glibc 2.1, struct sockaddr_in6 is 24 bytes.  In glibc 2.2
         * and in the 2.4 kernel, struct sockaddr_in6 has the scope_id
         * field and is 28 bytes.  It is possible for socket functions
         * to return an addr_len greater than sizeof(struct sockaddr_in6).
         * We need to allow that.  (Bugzilla bug #77264)
         */
        if ((PR_AF_INET6 == addr->raw.family)
                && (sizeof(addr->ipv6) == addr_len)) {
            return PR_TRUE;
        }
#endif
        return PR_FALSE;
    }
    return PR_TRUE;
}

#endif /* DEBUG */

/*****************************************************************************/
/************************* I/O Continuation machinery ************************/
/*****************************************************************************/

/*
 * The polling interval defines the maximum amount of time that a thread
 * might hang up before an interrupt is noticed.
 */
#define PT_DEFAULT_POLL_MSEC 5000
#if defined(_PR_POLL_WITH_SELECT)
#define PT_DEFAULT_SELECT_SEC (PT_DEFAULT_POLL_MSEC/PR_MSEC_PER_SEC)
#define PT_DEFAULT_SELECT_USEC							\
		((PT_DEFAULT_POLL_MSEC % PR_MSEC_PER_SEC) * PR_USEC_PER_MSEC)
#endif

/*
 * pt_SockLen is the type for the length of a socket address
 * structure, used in the address length argument to bind,
 * connect, accept, getsockname, getpeername, etc.  Posix.1g
 * defines this type as socklen_t.  It is size_t or int on
 * most current systems.
 */
#if defined(HAVE_SOCKLEN_T) \
    || (defined(LINUX) && defined(__GLIBC__) && __GLIBC__ >= 2)
typedef socklen_t pt_SockLen;
#elif (defined(AIX) && !defined(AIX4_1)) \
    || defined(VMS)
typedef PRSize pt_SockLen;
#else
typedef PRIntn pt_SockLen;
#endif

typedef struct pt_Continuation pt_Continuation;
typedef PRBool (*ContinuationFn)(pt_Continuation *op, PRInt16 revents);

typedef enum pr_ContuationStatus
{
    pt_continuation_pending,
    pt_continuation_done
} pr_ContuationStatus;

struct pt_Continuation
{
    /* The building of the continuation operation */
    ContinuationFn function;                /* what function to continue */
    union { PRIntn osfd; } arg1;            /* #1 - the op's fd */
    union { void* buffer; } arg2;           /* #2 - primary transfer buffer */
    union {
        PRSize amount;                      /* #3 - size of 'buffer', or */
        pt_SockLen *addr_len;                  /*    - length of address */
#ifdef HPUX11
        /*
         * For sendfile()
         */
		struct file_spec {		
        	off_t offset;                       /* offset in file to send */
        	size_t nbytes;                      /* length of file data to send */
        	size_t st_size;                     /* file size */
		} file_spec;
#endif
    } arg3;
    union { PRIntn flags; } arg4;           /* #4 - read/write flags */
    union { PRNetAddr *addr; } arg5;        /* #5 - send/recv address */

#ifdef HPUX11
    /*
     * For sendfile()
     */
    int filedesc;                           /* descriptor of file to send */
    int nbytes_to_send;                     /* size of header and file */
#endif  /* HPUX11 */
    
#ifdef SOLARIS
    /*
     * For sendfilev()
     */
    int nbytes_to_send;                     /* size of header and file */
#endif  /* SOLARIS */

#ifdef LINUX
    /*
     * For sendfile()
     */
    int in_fd;                              /* descriptor of file to send */
    off_t offset;
    size_t count;
#endif  /* LINUX */
 
    PRIntervalTime timeout;                 /* client (relative) timeout */

    PRInt16 event;                           /* flags for poll()'s events */

    /*
    ** The representation and notification of the results of the operation.
    ** These function can either return an int return code or a pointer to
    ** some object.
    */
    union { PRSize code; void *object; } result;

    PRIntn syserrno;                        /* in case it failed, why (errno) */
    pr_ContuationStatus status;             /* the status of the operation */
};

#if defined(DEBUG)

PTDebug pt_debug;  /* this is shared between several modules */

PR_IMPLEMENT(void) PT_GetStats(PTDebug* here) { *here = pt_debug; }

PR_IMPLEMENT(void) PT_FPrintStats(PRFileDesc *debug_out, const char *msg)
{
    PTDebug stats;
    char buffer[100];
    PRExplodedTime tod;
    PRInt64 elapsed, aMil;
    PT_GetStats(&stats);  /* a copy */
    PR_ExplodeTime(stats.timeStarted, PR_LocalTimeParameters, &tod);
    (void)PR_FormatTime(buffer, sizeof(buffer), "%T", &tod);

    LL_SUB(elapsed, PR_Now(), stats.timeStarted);
    LL_I2L(aMil, 1000000);
    LL_DIV(elapsed, elapsed, aMil);
    
    if (NULL != msg) PR_fprintf(debug_out, "%s", msg);
    PR_fprintf(
        debug_out, "\tstarted: %s[%lld]\n", buffer, elapsed);
    PR_fprintf(
        debug_out, "\tlocks [created: %u, destroyed: %u]\n",
        stats.locks_created, stats.locks_destroyed);
    PR_fprintf(
        debug_out, "\tlocks [acquired: %u, released: %u]\n",
        stats.locks_acquired, stats.locks_released);
    PR_fprintf(
        debug_out, "\tcvars [created: %u, destroyed: %u]\n",
        stats.cvars_created, stats.cvars_destroyed);
    PR_fprintf(
        debug_out, "\tcvars [notified: %u, delayed_delete: %u]\n",
        stats.cvars_notified, stats.delayed_cv_deletes);
}  /* PT_FPrintStats */

#endif  /* DEBUG */

#if defined(_PR_POLL_WITH_SELECT)
/*
 * OSF1 and HPUX report the POLLHUP event for a socket when the
 * shutdown(SHUT_WR) operation is called for the remote end, even though
 * the socket is still writeable. Use select(), instead of poll(), to
 * workaround this problem.
 */
static void pt_poll_now_with_select(pt_Continuation *op)
{
    PRInt32 msecs;
	fd_set rd, wr, *rdp, *wrp;
	struct timeval tv;
	PRIntervalTime epoch, now, elapsed, remaining;
	PRBool wait_for_remaining;
    PRThread *self = PR_GetCurrentThread();
    
	PR_ASSERT(PR_INTERVAL_NO_WAIT != op->timeout);
	PR_ASSERT(op->arg1.osfd < FD_SETSIZE);

    switch (op->timeout) {
        case PR_INTERVAL_NO_TIMEOUT:
			tv.tv_sec = PT_DEFAULT_SELECT_SEC;
			tv.tv_usec = PT_DEFAULT_SELECT_USEC;
			do
			{
				PRIntn rv;

				if (op->event & POLLIN) {
					FD_ZERO(&rd);
					FD_SET(op->arg1.osfd, &rd);
					rdp = &rd;
				} else
					rdp = NULL;
				if (op->event & POLLOUT) {
					FD_ZERO(&wr);
					FD_SET(op->arg1.osfd, &wr);
					wrp = &wr;