Commit bd5a48fe authored by Bill Stoddard's avatar Bill Stoddard
Browse files

Get mod_rewrite working with APR locks 

This has been tested on Linux and works (with the caveats:
must use --disable-hsregex, must define NO_DBM_REWRITEMAP,
must remove Dirks March 14 patch from util.c and httpd_config.c).

Submitted by:	Paul Reder
Reviewed by:	Bill Stoddard


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@84829 13f79535-47bb-0310-9956-ffa450edef68
parent effbc621

modules/mappers/mod_rewrite.c

+20 −151
Changes for modules/mappers/mod_rewrite.c: 20 added lines, 151 removed lines.
Original line number Diff line number Diff line
@@ -230,7 +230,8 @@ static int proxy_available; 
static int once_through = 0;



static const char *lockname;

static ap_file_t *lockfd = NULL;

static ap_lock_t *rewrite_map_lock = NULL;

static ap_lock_t *rewrite_log_lock = NULL;



/*

** +-------------------------------------------------------+
@@ -964,7 +965,12 @@ static void init_module(ap_context_t *p, 
    /* check if proxy module is available */

    proxy_available = (ap_find_linked_module("mod_proxy.c") != NULL);



    /* create the rewriting lockfile in the parent */

    /* create the rewriting lockfiles in the parent */

    if (ap_create_lock (&rewrite_log_lock, APR_MUTEX, APR_INTRAPROCESS,

                        NULL, NULL) != APR_SUCCESS)

        exit(1);    /* ugly but I can't log anything yet. This is what */

                    /*   the pre-existing rewritelock_create code did. */



    rewritelock_create(s, p);

    ap_register_cleanup(p, (void *)s, rewritelock_remove, ap_null_cleanup);
@@ -991,8 +997,9 @@ static void init_module(ap_context_t *p, 


static void init_child(ap_context_t *p, server_rec *s)

{

     /* open the rewriting lockfile */

     rewritelock_open(s, p);



    if (lockname != NULL && *(lockname) != '\0')

        ap_child_init_lock (&rewrite_map_lock, lockname, p);



    /* create the lookup cache */

    cachep = init_cache(p);
@@ -2978,7 +2985,8 @@ static char *lookup_map_program(request_rec *r, ap_file_t *fpin, 
    }



    /* take the lock */

    rewritelock_alloc(r);



    ap_lock(rewrite_map_lock);



    /* write out the request key */

#ifdef NO_WRITEV
@@ -3009,7 +3017,7 @@ static char *lookup_map_program(request_rec *r, ap_file_t *fpin, 
    buf[i] = '\0';



    /* give the lock back */

    rewritelock_free(r);

    ap_unlock(rewrite_map_lock);



    if (strcasecmp(buf, "NULL") == 0) {

        return NULL;
@@ -3259,10 +3267,10 @@ static void rewritelog(request_rec *r, int level, const char *text, ...) 
                (unsigned long)(r->server), (unsigned long)r,

                type, redir, level, str2);



    fd_lock(r, conf->rewritelogfp);

    ap_lock(rewrite_log_lock);

    nbytes = strlen(str3);

    ap_write(conf->rewritelogfp, str3, &nbytes);

    fd_unlock(r, conf->rewritelogfp);

    ap_unlock(rewrite_log_lock);



    va_end(ap);

    return;
@@ -3298,11 +3306,8 @@ static char *current_logtime(request_rec *r) 


static void rewritelock_create(server_rec *s, ap_context_t *p)

{

    rewrite_server_conf *conf;

    ap_status_t rc;



    conf = ap_get_module_config(s->module_config, &rewrite_module);



    /* only operate if a lockfile is used */

    if (lockname == NULL || *(lockname) == '\0') {

        return;
@@ -3312,76 +3317,26 @@ static void rewritelock_create(server_rec *s, ap_context_t *p) 
    lockname = ap_server_root_relative(p, lockname);



    /* create the lockfile */

    unlink(lockname);

    rc = ap_open(&lockfd, lockname, APR_WRITE | APR_CREATE, REWRITELOCK_MODE, p);

    rc = ap_create_lock (&rewrite_map_lock, APR_MUTEX, APR_LOCKALL, lockname, p);

    if (rc != APR_SUCCESS) {

        ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,

                     "mod_rewrite: Parent could not create RewriteLock "

                     "file %s", lockname);

        exit(1);

    }

#if !defined(OS2) && !defined(WIN32) && !defined(NETWARE)

    /* make sure the childs have access to this file */

    if (geteuid() == 0 /* is superuser */)

        chown(lockname, unixd_config.user_id, -1 /* no gid change */);

#endif



    return;

}



static void rewritelock_open(server_rec *s, ap_context_t *p)

{

    rewrite_server_conf *conf;

    ap_status_t rc;



    conf = ap_get_module_config(s->module_config, &rewrite_module);



    /* only operate if a lockfile is used */

    if (lockname == NULL || *(lockname) == '\0') {

        return;

    }



    /* open the lockfile (once per child) to get a unique fd */

    rc = ap_open(&lockfd, lockname, APR_WRITE | APR_CREATE, REWRITELOCK_MODE, p);

    if (rc != APR_SUCCESS) {

        ap_log_error(APLOG_MARK, APLOG_ERR, 0, s,

                     "mod_rewrite: Child could not open RewriteLock "

                     "file %s", lockname);

        exit(1);

    }

    return;

}



static ap_status_t rewritelock_remove(void *data)

{

    /* only operate if a lockfile is used */

    if (lockname == NULL || *(lockname) == '\0') {

        return(-1);

    }



    /* remove the lockfile */

    unlink(lockname);

    /* destroy the rewritelock */

    ap_destroy_lock (rewrite_map_lock);

    rewrite_map_lock = NULL;

    lockname = NULL;

    lockfd = NULL;

    return(0);

}



static void rewritelock_alloc(request_rec *r)

{

    if (lockfd != NULL) {

        fd_lock(r, lockfd);

    }

    return;

}



static void rewritelock_free(request_rec *r)

{

    if (lockfd != NULL) {

        fd_unlock(r, lockfd);

    }

    return;

}





/*

** +-------------------------------------------------------+
@@ -4194,92 +4149,6 @@ static int prefix_stat(const char *path, struct stat *sb) 
}





/*

**

**  File locking

**

*/



#ifdef USE_FCNTL

static struct flock   lock_it;

static struct flock unlock_it;

#endif



static void fd_lock(request_rec *r, ap_file_t *fd)

{

    int rc;

    int sys_file;



#ifdef USE_FCNTL

    lock_it.l_whence = SEEK_SET; /* from current point */

    lock_it.l_start  = 0;        /* -"- */

    lock_it.l_len    = 0;        /* until end of file */

    lock_it.l_type   = F_WRLCK;  /* set exclusive/write lock */

    lock_it.l_pid    = 0;        /* pid not actually interesting */



    ap_get_os_file(&sys_file, fd);

    while (   ((rc = fcntl(sys_file, F_SETLKW, &lock_it)) < 0)

              && (errno == EINTR)                               ) {

        continue;

    }

#endif

#ifdef USE_FLOCK

    ap_get_os_file(fd, &sys_file);

    while (   ((rc = flock(sys_file, LOCK_EX)) < 0)

              && (errno == EINTR)               ) {

        continue;

    }

#endif

#ifdef USE_LOCKING

    /* Lock the first byte, always, assume we want to append

       and seek to the end afterwards */

    ap_seek(fd, APR_SET, 0);

    ap_get_os_file(&sys_file, fd);

    rc = _locking(sys_file, _LK_LOCK, 1);

    ap_seek(fd, APR_END, 0);

#endif



    if (rc < 0) {

        ap_log_rerror(APLOG_MARK, APLOG_ERR, errno, r,

                     "mod_rewrite: failed to lock file descriptor");

        exit(1);

    }

    return;

}



static void fd_unlock(request_rec *r, ap_file_t *fd)

{

    int rc;

    int sys_file;



#ifdef USE_FCNTL

    unlock_it.l_whence = SEEK_SET; /* from current point */

    unlock_it.l_start  = 0;        /* -"- */

    unlock_it.l_len    = 0;        /* until end of file */

    unlock_it.l_type   = F_UNLCK;  /* unlock */

    unlock_it.l_pid    = 0;        /* pid not actually interesting */



    ap_get_os_file(&sys_file, fd);

    rc = fcntl(sys_file, F_SETLKW, &unlock_it);

#endif

#ifdef USE_FLOCK

    ap_get_os_file(fd, &sys_file);

    rc = flock(sys_file, LOCK_UN);

#endif

#ifdef USE_LOCKING

    ap_seek(fd, APR_SET, 0);

    ap_get_os_file(&sys_file, fd);

    rc = _locking(sys_file, _LK_UNLCK, 1);

    ap_seek(fd, APR_END, 0);

#endif



    if (rc < 0) {

        ap_log_rerror(APLOG_MARK, APLOG_ERR, errno, r,

                     "mod_rewrite: failed to unlock file descriptor");

        exit(1);

    }

}



/*

**

**  Lexicographic Compare

modules/mappers/mod_rewrite.h

+0 −42
Changes for modules/mappers/mod_rewrite.h: 0 added lines, 42 removed lines.
Original line number Diff line number Diff line
@@ -145,41 +145,6 @@ 
#endif





    /* The locking support:

     * Try to determine whether we should use fcntl() or flock().

     * Would be better ap_config.h could provide this... :-(

     */

#if defined(USE_FCNTL_SERIALIZED_ACCEPT)

#define USE_FCNTL 1

#include <fcntl.h>

#endif

#if defined(USE_FLOCK_SERIALIZED_ACCEPT)

#define USE_FLOCK 1

#include <sys/file.h>

#endif

#if !defined(USE_FCNTL) && !defined(USE_FLOCK)

#define USE_FLOCK 1

#if !defined(MPE) && !defined(WIN32) && !defined(__TANDEM) && !defined(NETWARE)

#include <sys/file.h>

#endif

#ifndef LOCK_UN

#undef USE_FLOCK

#define USE_FCNTL 1

#include <fcntl.h>

#endif

#endif

#ifdef AIX

#undef USE_FLOCK

#define USE_FCNTL 1

#include <fcntl.h>

#endif

#ifdef WIN32

#undef USE_FCNTL

#define USE_LOCKING

#include <sys/locking.h>

#endif





/*

**

**  Some defines
@@ -459,10 +424,7 @@ static char *current_logtime(request_rec *r); 


    /* rewriting lockfile support */

static void rewritelock_create(server_rec *s, ap_context_t *p);

static void rewritelock_open(server_rec *s, ap_context_t *p);

static ap_status_t rewritelock_remove(void *data);

static void rewritelock_alloc(request_rec *r);

static void rewritelock_free(request_rec *r);



    /* program map support */

static void  run_rewritemap_programs(server_rec *s, ap_context_t *p);
@@ -492,10 +454,6 @@ static int parseargline(char *str, char **a1, char **a2, char **a3); 
static int    prefix_stat(const char *path, struct stat *sb);

static void   add_env_variable(request_rec *r, char *s);



    /* File locking */

static void fd_lock(request_rec *r, ap_file_t *fd);

static void fd_unlock(request_rec *r, ap_file_t *fd);



    /* Lexicographic Comparison */

static int compare_lexicography(char *cpNum1, char *cpNum2);