locks.c

Apache V2.0.15 Alpha For Linuxhttpd-2_0_15-alpha.tar.Z

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#include "apr_general.h"
#include "apr_strings.h"
#include "win32/locks.h"
#include "apr_portable.h"

APR_DECLARE(apr_status_t) apr_lock_create(apr_lock_t **lock, 
                                          apr_locktype_e type, 
                                          apr_lockscope_e scope, 
                                          const char *fname,
                                          apr_pool_t *cont)
{
    apr_lock_t *newlock;
    SECURITY_ATTRIBUTES sec;

    newlock = (apr_lock_t *)apr_palloc(cont, sizeof(apr_lock_t));

    newlock->cntxt = cont;
    /* ToDo:  How to handle the case when no context is available? 
    *         How to cleanup the storage properly?
    */
    newlock->fname = apr_pstrdup(cont, fname);
    newlock->type = type;
    newlock->scope = scope;
    sec.nLength = sizeof(SECURITY_ATTRIBUTES);
    sec.lpSecurityDescriptor = NULL;

    if (scope == APR_CROSS_PROCESS || scope == APR_LOCKALL) {
        sec.bInheritHandle = TRUE;
    }
    else {
        sec.bInheritHandle = FALSE;
    }

    if (scope == APR_INTRAPROCESS) {
        InitializeCriticalSection(&newlock->section);
    } else {
        newlock->mutex = CreateMutex(&sec, FALSE, fname);
    }
    *lock = newlock;
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_lock_child_init(apr_lock_t **lock, 
                                              const char *fname, 
                                              apr_pool_t *cont)
{
    /* This routine should not be called (and OpenMutex will fail if called) 
     * on a INTRAPROCESS lock
     */
    (*lock) = (apr_lock_t *)apr_palloc(cont, sizeof(apr_lock_t));

    if ((*lock) == NULL) {
        return APR_ENOMEM;
    }
    (*lock)->fname = apr_pstrdup(cont, fname);
    (*lock)->mutex = OpenMutex(MUTEX_ALL_ACCESS, TRUE, fname);
    
    if ((*lock)->mutex == NULL) {
        return apr_get_os_error();
    }
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_lock_acquire(apr_lock_t *lock)
{
    DWORD rv;
    if (lock->scope == APR_INTRAPROCESS) {
        EnterCriticalSection(&lock->section);
        return APR_SUCCESS;
    } else {
        rv = WaitForSingleObject(lock->mutex, INFINITE);

        if (rv == WAIT_OBJECT_0 || rv == WAIT_ABANDONED) {
            return APR_SUCCESS;
        }
    }
    return apr_get_os_error();
}

APR_DECLARE(apr_status_t) apr_lock_release(apr_lock_t *lock)
{
    if (lock->scope == APR_INTRAPROCESS) {
        LeaveCriticalSection(&lock->section);
        return APR_SUCCESS;
    } else {
        if (ReleaseMutex(lock->mutex) == 0) {
            return apr_get_os_error();
        }
    }
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_lock_destroy(apr_lock_t *lock)
{
    if (lock->scope == APR_INTRAPROCESS) {
        DeleteCriticalSection(&lock->section);
        return APR_SUCCESS;
    } else {
        if (CloseHandle(lock->mutex) == 0) {
            return apr_get_os_error();
        }
    }
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_lock_data_get(apr_lock_t *lock, const char *key,
                                           void *data)
{
    return apr_pool_userdata_get(data, key, lock->cntxt);
}

APR_DECLARE(apr_status_t) apr_lock_data_set(apr_lock_t *lock, void *data,
                                           const char *key,
                                           apr_status_t (*cleanup) (void *))
{
    return apr_pool_userdata_set(data, key, cleanup, lock->cntxt);
}

APR_DECLARE(apr_status_t) apr_os_lock_get(apr_os_lock_t *thelock,
                                          apr_lock_t *lock)
{
    *thelock = lock->mutex;
    return APR_SUCCESS;
}

APR_DECLARE(apr_status_t) apr_os_lock_put(apr_lock_t **lock,
                                          apr_os_lock_t *thelock,
                                          apr_pool_t *cont)
{
    if (cont == NULL) {
        return APR_ENOPOOL;
    }
    if ((*lock) == NULL) {
        (*lock) = (apr_lock_t *)apr_palloc(cont, sizeof(apr_lock_t));
        (*lock)->cntxt = cont;
    }
    (*lock)->mutex = *thelock;
    return APR_SUCCESS;
}