ap_hook.c

apach加密模块

    ap_hook_value modeval;
    ap_hook_entry *he;
    va_list ap;
    int rc;

    va_start(ap, modeid);

    if (modeid == AP_HOOK_MODE_DECLINE || modeid == AP_HOOK_MODE_DECLTMP) {
        if (AP_HOOK_SIG_HAS(sig, RC, char))
            modeval.v_char = va_arg(ap, va_type(char));
        else if (AP_HOOK_SIG_HAS(sig, RC, int))
            modeval.v_int = va_arg(ap, va_type(int));
        else if (AP_HOOK_SIG_HAS(sig, RC, long))
            modeval.v_long = va_arg(ap, va_type(long));
        else if (AP_HOOK_SIG_HAS(sig, RC, float))
            modeval.v_float = va_arg(ap, va_type(float));
        else if (AP_HOOK_SIG_HAS(sig, RC, double))
            modeval.v_double = va_arg(ap, va_type(double));
        else if (AP_HOOK_SIG_HAS(sig, RC, ptr))
            modeval.v_ptr = va_arg(ap, va_type(ptr));
    }

    if ((he = ap_hook_create(hook)) == NULL)
        return FALSE;

    if (he->he_sig == AP_HOOK_SIG_UNKNOWN)
        he->he_sig = sig;
    if (he->he_modeid == AP_HOOK_MODE_UNKNOWN) {
        he->he_modeid  = modeid;
        he->he_modeval = modeval;
    }

    for (i = 0; he->he_func[i] != NULL; i++)
        if (ap_hook_call_func(ap, he, he->he_func[i]))
            break;

    if (i > 0 && he->he_modeid == AP_HOOK_MODE_ALL)
        rc = TRUE;
    else if (i == AP_HOOK_MAX_FUNCS || he->he_func[i] == NULL)
        rc = FALSE;
    else
        rc = TRUE;

    va_end(ap);
    return rc;
}

/*
 * Call a hook
 */
API_EXPORT(int) ap_hook_call(char *hook, ...)
{
    int i;
    ap_hook_entry *he;
    va_list ap;
    int rc;
    
    va_start(ap, hook);

    if ((he = ap_hook_find(hook)) == NULL) {
        va_end(ap);
        return FALSE;
    }
    if (   he->he_sig == AP_HOOK_SIG_UNKNOWN
        || he->he_modeid == AP_HOOK_MODE_UNKNOWN) {
        va_end(ap);
        return FALSE;
    }

    for (i = 0; he->he_func[i] != NULL; i++)
        if (ap_hook_call_func(ap, he, he->he_func[i]))
            break;

    if (i > 0 && he->he_modeid == AP_HOOK_MODE_ALL)
        rc = TRUE;
    else if (i == AP_HOOK_MAX_FUNCS || he->he_func[i] == NULL)
        rc = FALSE;
    else
        rc = TRUE;

    va_end(ap);
    return rc;
}

static int ap_hook_call_func(va_list ap, ap_hook_entry *he, ap_hook_func *hf)
{
    void *v_rc;
    ap_hook_value v_tmp;
    int rc;

    /*
     * Now we dispatch the various function calls. We support function
     * signatures with up to 9 types (1 return type, 8 argument types) where
     * each argument can have 7 different types (ctx, char, int, long, float,
     * double, ptr), so theoretically there are 9^7 (=4782969) combinations
     * possible.  But because we don't need all of them, of course, we
     * implement only the following well chosen subset (duplicates are ok):
     *
     * 1. `The basic hook'.
     *
     *    void func()
     *
     * 2. The standard set of signatures which form all combinations of
     *    int&ptr based signatures for up to 3 arguments. We provide
     *    them per default for module authors.
     *
     *    int func()
     *    ptr func()
     *    int func(int)
     *    int func(ptr)
     *    ptr func(int)
     *    ptr func(ptr)
     *    int func(int,int)
     *    int func(int,ptr)
     *    int func(ptr,int)
     *    int func(ptr,ptr)
     *    ptr func(int,int)
     *    ptr func(int,ptr)
     *    ptr func(ptr,int)
     *    ptr func(ptr,ptr)
     *    int func(int,int,int)
     *    int func(int,int,ptr)
     *    int func(int,ptr,int)
     *    int func(int,ptr,ptr)
     *    int func(ptr,int,int)
     *    int func(ptr,int,ptr)
     *    int func(ptr,ptr,int)
     *    int func(ptr,ptr,ptr)
     *    ptr func(int,int,int)
     *    ptr func(int,int,ptr)
     *    ptr func(int,ptr,int)
     *    ptr func(int,ptr,ptr)
     *    ptr func(ptr,int,int)
     *    ptr func(ptr,int,ptr)
     *    ptr func(ptr,ptr,int)
     *    ptr func(ptr,ptr,ptr)
     *
     * 3. Actually currently used hooks.
     *
     *    int   func(ptr)                          [2x]
     *    int   func(ptr,ptr)                      [2x]
     *    int   func(ptr,ptr,int)                  [5x]
     *    int   func(ptr,ptr,ptr,int)              [1x]
     *    int   func(ptr,ptr,ptr,int,ptr)          [1x]
     *    int   func(ptr,ptr,ptr,ptr,int)          [1x]
     *    int   func(ptr,ptr,ptr,ptr,int,ptr)      [1x]
     *    ptr   func(ptr,ptr)                      [3x]
     *    ptr   func(ptr,ptr,ptr,ptr,ptr)          [1x]
     *    void  func(ptr)                          [2x]
     *    void  func(ptr,int,int)                  [1x]
     *    void  func(ptr,ptr)                      [5x]
     *    void  func(ptr,ptr,ptr)                  [3x]
     *    void  func(ptr,ptr,ptr,ptr)              [2x]
     *
     * To simplify the programming task we generate the actual dispatch code
     * for these calls via the embedded Perl script at the end of this source
     * file. This script parses the above lines and generates the section
     * below.  So, when you need more signature variants just add them to the
     * above list and run
     *
     *     $ perl ap_hook.c
     *
     * This automatically updates the above code.
     */

    rc = TRUE;
    v_rc = NULL;
    if (!AP_HOOK_SIG_HAS(he->he_sig, RC, void)) {
        if (he->he_modeid == AP_HOOK_MODE_DECLTMP) {
            /* the return variable is a temporary one */ 
            if (AP_HOOK_SIG_HAS(he->he_sig, RC, char))
                v_rc = &v_tmp.v_char;
            else if (AP_HOOK_SIG_HAS(he->he_sig, RC, int))
                v_rc = &v_tmp.v_int;
            else if (AP_HOOK_SIG_HAS(he->he_sig, RC, long))
                v_rc = &v_tmp.v_long;
            else if (AP_HOOK_SIG_HAS(he->he_sig, RC, float))
                v_rc = &v_tmp.v_float;
            else if (AP_HOOK_SIG_HAS(he->he_sig, RC, double))
                v_rc = &v_tmp.v_double;
            else if (AP_HOOK_SIG_HAS(he->he_sig, RC, ptr))
                v_rc = &v_tmp.v_ptr;
        }
        else {
            /* the return variable is provided by caller */ 
            v_rc = va_arg(ap, void *);
        }
    }

    /* ----BEGIN GENERATED SECTION-------- */
    if (he->he_sig == AP_HOOK_SIG1(void)) {
        /* Call: void func() */
        ((void(*)())(hf->hf_ptr))();
    }
    else if (he->he_sig == AP_HOOK_SIG1(int)) {
        /* Call: int func() */
        *((int *)v_rc) = ((int(*)())(hf->hf_ptr))();
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG1(ptr)) {
        /* Call: ptr func() */
        *((void * *)v_rc) = ((void *(*)())(hf->hf_ptr))();
        rc = (*((void * *)v_rc) != he->he_modeval.v_ptr);
    }
    else if (he->he_sig == AP_HOOK_SIG2(int, int)) {
        /* Call: int func(int) */
        int   v1 = va_arg(ap, va_type(int));
        *((int *)v_rc) = ((int(*)(int))(hf->hf_ptr))(v1);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG2(int, ptr)) {
        /* Call: int func(ptr) */
        void *v1 = va_arg(ap, va_type(ptr));
        *((int *)v_rc) = ((int(*)(void *))(hf->hf_ptr))(v1);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG2(ptr, int)) {
        /* Call: ptr func(int) */
        int   v1 = va_arg(ap, va_type(int));
        *((void * *)v_rc) = ((void *(*)(int))(hf->hf_ptr))(v1);
        rc = (*((void * *)v_rc) != he->he_modeval.v_ptr);
    }
    else if (he->he_sig == AP_HOOK_SIG2(ptr, ptr)) {
        /* Call: ptr func(ptr) */
        void *v1 = va_arg(ap, va_type(ptr));
        *((void * *)v_rc) = ((void *(*)(void *))(hf->hf_ptr))(v1);
        rc = (*((void * *)v_rc) != he->he_modeval.v_ptr);
    }
    else if (he->he_sig == AP_HOOK_SIG3(int, int, int)) {
        /* Call: int func(int,int) */
        int   v1 = va_arg(ap, va_type(int));
        int   v2 = va_arg(ap, va_type(int));
        *((int *)v_rc) = ((int(*)(int, int))(hf->hf_ptr))(v1, v2);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG3(int, int, ptr)) {
        /* Call: int func(int,ptr) */
        int   v1 = va_arg(ap, va_type(int));
        void *v2 = va_arg(ap, va_type(ptr));
        *((int *)v_rc) = ((int(*)(int, void *))(hf->hf_ptr))(v1, v2);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG3(int, ptr, int)) {
        /* Call: int func(ptr,int) */
        void *v1 = va_arg(ap, va_type(ptr));
        int   v2 = va_arg(ap, va_type(int));
        *((int *)v_rc) = ((int(*)(void *, int))(hf->hf_ptr))(v1, v2);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG3(int, ptr, ptr)) {
        /* Call: int func(ptr,ptr) */
        void *v1 = va_arg(ap, va_type(ptr));
        void *v2 = va_arg(ap, va_type(ptr));
        *((int *)v_rc) = ((int(*)(void *, void *))(hf->hf_ptr))(v1, v2);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG3(ptr, int, int)) {
        /* Call: ptr func(int,int) */
        int   v1 = va_arg(ap, va_type(int));
        int   v2 = va_arg(ap, va_type(int));
        *((void * *)v_rc) = ((void *(*)(int, int))(hf->hf_ptr))(v1, v2);
        rc = (*((void * *)v_rc) != he->he_modeval.v_ptr);
    }
    else if (he->he_sig == AP_HOOK_SIG3(ptr, int, ptr)) {
        /* Call: ptr func(int,ptr) */
        int   v1 = va_arg(ap, va_type(int));
        void *v2 = va_arg(ap, va_type(ptr));
        *((void * *)v_rc) = ((void *(*)(int, void *))(hf->hf_ptr))(v1, v2);
        rc = (*((void * *)v_rc) != he->he_modeval.v_ptr);
    }
    else if (he->he_sig == AP_HOOK_SIG3(ptr, ptr, int)) {
        /* Call: ptr func(ptr,int) */
        void *v1 = va_arg(ap, va_type(ptr));
        int   v2 = va_arg(ap, va_type(int));
        *((void * *)v_rc) = ((void *(*)(void *, int))(hf->hf_ptr))(v1, v2);
        rc = (*((void * *)v_rc) != he->he_modeval.v_ptr);
    }
    else if (he->he_sig == AP_HOOK_SIG3(ptr, ptr, ptr)) {
        /* Call: ptr func(ptr,ptr) */
        void *v1 = va_arg(ap, va_type(ptr));
        void *v2 = va_arg(ap, va_type(ptr));
        *((void * *)v_rc) = ((void *(*)(void *, void *))(hf->hf_ptr))(v1, v2);
        rc = (*((void * *)v_rc) != he->he_modeval.v_ptr);
    }
    else if (he->he_sig == AP_HOOK_SIG4(int, int, int, int)) {
        /* Call: int func(int,int,int) */
        int   v1 = va_arg(ap, va_type(int));
        int   v2 = va_arg(ap, va_type(int));
        int   v3 = va_arg(ap, va_type(int));
        *((int *)v_rc) = ((int(*)(int, int, int))(hf->hf_ptr))(v1, v2, v3);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG4(int, int, int, ptr)) {
        /* Call: int func(int,int,ptr) */
        int   v1 = va_arg(ap, va_type(int));
        int   v2 = va_arg(ap, va_type(int));
        void *v3 = va_arg(ap, va_type(ptr));
        *((int *)v_rc) = ((int(*)(int, int, void *))(hf->hf_ptr))(v1, v2, v3);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG4(int, int, ptr, int)) {
        /* Call: int func(int,ptr,int) */
        int   v1 = va_arg(ap, va_type(int));
        void *v2 = va_arg(ap, va_type(ptr));
        int   v3 = va_arg(ap, va_type(int));
        *((int *)v_rc) = ((int(*)(int, void *, int))(hf->hf_ptr))(v1, v2, v3);
        rc = (*((int *)v_rc) != he->he_modeval.v_int);
    }
    else if (he->he_sig == AP_HOOK_SIG4(int, int, ptr, ptr)) {
        /* Call: int func(int,ptr,ptr) */
        int   v1 = va_arg(ap, va_type(int));