dynamic.h

/* Simple Plugin API */
/* SPDX-FileCopyrightText: Copyright © 2018 Wim Taymans */
/* SPDX-License-Identifier: MIT */
 
#ifndef SPA_POD_DYNAMIC_H
#define SPA_POD_DYNAMIC_H
 
#include <spa/pod/builder.h>
#include <spa/utils/cleanup.h>
 
#ifdef __cplusplus
extern "C" {
#endif
 
#ifndef SPA_API_POD_DYNAMIC
 #ifdef SPA_API_IMPL
  #define SPA_API_POD_DYNAMIC SPA_API_IMPL
 #else
  #define SPA_API_POD_DYNAMIC static inline
 #endif
#endif
 
struct spa_pod_dynamic_builder {
        struct spa_pod_builder b;
        void *data;
        uint32_t extend;
        uint32_t _padding;
};
 
static int spa_pod_dynamic_builder_overflow(void *data, uint32_t size)
{
        struct spa_pod_dynamic_builder *d = (struct spa_pod_dynamic_builder*)data;
        int32_t old_size = d->b.size;
        int32_t new_size = SPA_ROUND_UP_N(size, d->extend);
        void *old_data = d->b.data, *new_data;
 
        if (old_data == d->data)
                d->b.data = NULL;
        if ((new_data = realloc(d->b.data, new_size)) == NULL)
                return -errno;
        if (old_data == d->data && new_data != old_data && old_size > 0)
                memcpy(new_data, old_data, old_size);
        d->b.data = new_data;
        d->b.size = new_size;
        return 0;
}
 
SPA_API_POD_DYNAMIC void spa_pod_dynamic_builder_init(struct spa_pod_dynamic_builder *builder,
                void *data, uint32_t size, uint32_t extend)
{
        static const struct spa_pod_builder_callbacks spa_pod_dynamic_builder_callbacks = {
                .version = SPA_VERSION_POD_BUILDER_CALLBACKS,
                .overflow = spa_pod_dynamic_builder_overflow
        };
        builder->b = SPA_POD_BUILDER_INIT(data, size);
        if (extend > 0)
                spa_pod_builder_set_callbacks(&builder->b, &spa_pod_dynamic_builder_callbacks, builder);
        builder->extend = extend;
        builder->data = data;
}
 
SPA_API_POD_DYNAMIC void spa_pod_dynamic_builder_continue(struct spa_pod_dynamic_builder *builder,
                struct spa_pod_builder *b)
{
        uint32_t remain = b->state.offset >= b->size ? 0 : b->size - b->state.offset;
        spa_pod_dynamic_builder_init(builder,
                        remain ? SPA_PTROFF(b->data, b->state.offset, void) : NULL,
                        remain, b->callbacks.funcs == NULL ? 0 : 4096);
}
 
SPA_API_POD_DYNAMIC void spa_pod_dynamic_builder_clean(struct spa_pod_dynamic_builder *builder)
{
        if (builder->data != builder->b.data) {
                free(builder->b.data);
                builder->b.data = NULL;
        }
}
 
SPA_DEFINE_AUTO_CLEANUP(spa_pod_dynamic_builder, struct spa_pod_dynamic_builder, {
        spa_pod_dynamic_builder_clean(thing);
})
 
#ifdef __cplusplus
}  /* extern "C" */
#endif
 
#endif /* SPA_POD_DYNAMIC_H */