compare.h

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/* Simple Plugin API
 *
 * Copyright © 2018 Wim Taymans
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */
 
#ifndef SPA_POD_COMPARE_H
#define SPA_POD_COMPARE_H
 
#ifdef __cplusplus
extern "C" {
#endif
 
#include <stdarg.h>
#include <errno.h>
#include <stdint.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
 
#include <spa/param/props.h>
#include <spa/pod/iter.h>
#include <spa/pod/builder.h>
 
static inline int spa_pod_compare_value(uint32_t type, const void *r1, const void *r2, uint32_t size)
{
        switch (type) {
        case SPA_TYPE_None:
                return 0;
        case SPA_TYPE_Bool:
        case SPA_TYPE_Id:
                return *(uint32_t *) r1 == *(uint32_t *) r2 ? 0 : 1;
        case SPA_TYPE_Int:
                return *(int32_t *) r1 - *(int32_t *) r2;
        case SPA_TYPE_Long:
                return *(int64_t *) r1 - *(int64_t *) r2;
        case SPA_TYPE_Float:
                return *(float *) r1 - *(float *) r2;
        case SPA_TYPE_Double:
                return *(double *) r1 - *(double *) r2;
        case SPA_TYPE_String:
                return strcmp((char *)r1, (char *)r2);
        case SPA_TYPE_Bytes:
                return memcmp((char *)r1, (char *)r2, size);
        case SPA_TYPE_Rectangle:
        {
                const struct spa_rectangle *rec1 = (struct spa_rectangle *) r1,
                    *rec2 = (struct spa_rectangle *) r2;
                if (rec1->width == rec2->width && rec1->height == rec2->height)
                        return 0;
                else if (rec1->width < rec2->width || rec1->height < rec2->height)
                        return -1;
                else
                        return 1;
        }
        case SPA_TYPE_Fraction:
        {
                const struct spa_fraction *f1 = (struct spa_fraction *) r1,
                    *f2 = (struct spa_fraction *) r2;
                int64_t n1, n2;
                n1 = ((int64_t) f1->num) * f2->denom;
                n2 = ((int64_t) f2->num) * f1->denom;
                if (n1 < n2)
                        return -1;
                else if (n1 > n2)
                        return 1;
                else
                        return 0;
        }
        default:
                break;
        }
        return 0;
}
 
static inline int spa_pod_compare(const struct spa_pod *pod1,
                                  const struct spa_pod *pod2)
{
        int res = 0;
        uint32_t n_vals1, n_vals2;
        uint32_t choice1, choice2;
 
        spa_return_val_if_fail(pod1 != NULL, -EINVAL);
        spa_return_val_if_fail(pod2 != NULL, -EINVAL);
 
        pod1 = spa_pod_get_values(pod1,  &n_vals1, &choice1);
        pod2 = spa_pod_get_values(pod2,  &n_vals2, &choice2);
 
        if (n_vals1 != n_vals2)
                return -EINVAL;
 
        if (SPA_POD_TYPE(pod1) != SPA_POD_TYPE(pod2))
                return -EINVAL;
 
        switch (SPA_POD_TYPE(pod1)) {
        case SPA_TYPE_Struct:
        {
                const struct spa_pod *p1, *p2;
                size_t p1s, p2s;
 
                p1 = (const struct spa_pod*)SPA_POD_BODY_CONST(pod1);
                p1s = SPA_POD_BODY_SIZE(pod1);
                p2 = (const struct spa_pod*)SPA_POD_BODY_CONST(pod2);
                p2s = SPA_POD_BODY_SIZE(pod2);
 
                while (true) {
                        if (!spa_pod_is_inside(pod1, p1s, p1) ||
                            !spa_pod_is_inside(pod2, p2s, p2))
                                return -EINVAL;
 
                        if ((res = spa_pod_compare(p1, p2)) != 0)
                                return res;
 
                        p1 = (const struct spa_pod*)spa_pod_next(p1);
                        p2 = (const struct spa_pod*)spa_pod_next(p2);
                }
                break;
        }
        case SPA_TYPE_Object:
        {
                const struct spa_pod_prop *p1, *p2;
                const struct spa_pod_object *o1, *o2;
 
                o1 = (const struct spa_pod_object*)pod1;
                o2 = (const struct spa_pod_object*)pod2;
 
                p2 = NULL;
                SPA_POD_OBJECT_FOREACH(o1, p1) {
                        if ((p2 = spa_pod_object_find_prop(o2, p2, p1->key)) == NULL)
                                return 1;
                        if ((res = spa_pod_compare(&p1->value, &p2->value)) != 0)
                                return res;
                }
                p1 = NULL;
                SPA_POD_OBJECT_FOREACH(o2, p2) {
                        if ((p1 = spa_pod_object_find_prop(o1, p1, p2->key)) == NULL)
                                return -1;
                }
                break;
        }
        case SPA_TYPE_Array:
        {
                if (SPA_POD_BODY_SIZE(pod1) != SPA_POD_BODY_SIZE(pod2))
                        return -EINVAL;
                res = memcmp(SPA_POD_BODY(pod1), SPA_POD_BODY(pod2), SPA_POD_BODY_SIZE(pod2));
                break;
        }
        default:
                if (SPA_POD_BODY_SIZE(pod1) != SPA_POD_BODY_SIZE(pod2))
                        return -EINVAL;
                res = spa_pod_compare_value(SPA_POD_TYPE(pod1),
                                SPA_POD_BODY(pod1), SPA_POD_BODY(pod2),
                                SPA_POD_BODY_SIZE(pod1));
                break;
        }
        return res;
}
 
#ifdef __cplusplus
}
#endif
 
#endif