local-v4l2.c

Using libspa-v4l2

/* PipeWire */
/* SPDX-FileCopyrightText: Copyright © 2018 Wim Taymans */
/* SPDX-License-Identifier: MIT */
 
/*
 [title]
 Using libspa-v4l2
 [title]
 */
 
#include <stdio.h>
#include <sys/mman.h>
 
#define WIDTH   640
#define HEIGHT  480
#define BPP    3
#define MAX_BUFFERS     32
 
#include "sdl.h"
 
#include <spa/param/video/format-utils.h>
#include <spa/param/props.h>
#include <spa/pod/filter.h>
#include <spa/node/io.h>
#include <spa/node/utils.h>
#include <spa/debug/format.h>
#include <spa/utils/names.h>
 
#include <pipewire/impl.h>
 
struct data {
        SDL_Renderer *renderer;
        SDL_Window *window;
        SDL_Texture *texture;
 
        struct pw_main_loop *loop;
 
        struct pw_context *context;
        struct pw_core *core;
 
        struct spa_port_info info;
        struct spa_param_info params[4];
 
        struct spa_node impl_node;
        struct spa_io_buffers *io;
 
        struct spa_hook_list hooks;
 
        struct spa_video_info_raw format;
        int32_t stride;
 
        struct spa_buffer *buffers[MAX_BUFFERS];
        int n_buffers;
 
        struct pw_proxy *out, *in, *link;
};
 
static void handle_events(struct data *data)
{
        SDL_Event event;
        while (SDL_PollEvent(&event)) {
                switch (event.type) {
                case SDL_QUIT:
                        pw_main_loop_quit(data->loop);
                        break;
                }
        }
}
 
static int impl_set_io(void *object, uint32_t id, void *data, size_t size)
{
        return 0;
}
 
static int impl_send_command(void *object, const struct spa_command *command)
{
        return 0;
}
 
static int impl_add_listener(void *object,
                struct spa_hook *listener,
                const struct spa_node_events *events,
                void *data)
{
        struct data *d = object;
        struct spa_hook_list save;
 
        spa_hook_list_isolate(&d->hooks, &save, listener, events, data);
 
        spa_node_emit_port_info(&d->hooks, SPA_DIRECTION_INPUT, 0, &d->info);
 
        spa_hook_list_join(&d->hooks, &save);
 
        return 0;
}
 
static int impl_set_callbacks(void *object,
                              const struct spa_node_callbacks *callbacks, void *data)
{
        return 0;
}
 
static int impl_port_set_io(void *object, enum spa_direction direction, uint32_t port_id,
                            uint32_t id, void *data, size_t size)
{
        struct data *d = object;
 
        if (id == SPA_IO_Buffers)
                d->io = data;
        else
                return -ENOENT;
 
        return 0;
}
 
static int impl_port_enum_params(void *object, int seq,
                                 enum spa_direction direction, uint32_t port_id,
                                 uint32_t id, uint32_t start, uint32_t num,
                                 const struct spa_pod *filter)
{
        struct data *d = object;
        struct spa_pod *param;
        struct spa_pod_builder b = { 0 };
        uint8_t buffer[1024];
        struct spa_result_node_params result;
        uint32_t count = 0;
 
        result.id = id;
        result.next = start;
      next:
        result.index = result.next++;
 
        spa_pod_builder_init(&b, buffer, sizeof(buffer));
 
        switch (id) {
        case SPA_PARAM_EnumFormat:
        {
                SDL_RendererInfo info;
 
                if (result.index > 0)
                        return 0;
 
                SDL_GetRendererInfo(d->renderer, &info);
                param = sdl_build_formats(&info, &b);
                break;
        }
        case SPA_PARAM_Buffers:
                if (result.index > 0)
                        return 0;
 
                param = spa_pod_builder_add_object(&b,
                        SPA_TYPE_OBJECT_ParamBuffers, id,
                        SPA_PARAM_BUFFERS_buffers, SPA_POD_CHOICE_RANGE_Int(2, 1, 32),
                        SPA_PARAM_BUFFERS_blocks,  SPA_POD_Int(1),
                        SPA_PARAM_BUFFERS_size,    SPA_POD_Int(d->stride * d->format.size.height),
                        SPA_PARAM_BUFFERS_stride,  SPA_POD_Int(d->stride));
                break;
 
        case SPA_PARAM_Meta:
                if (result.index > 0)
                        return 0;
 
                param = spa_pod_builder_add_object(&b,
                        SPA_TYPE_OBJECT_ParamMeta, id,
                        SPA_PARAM_META_type, SPA_POD_Id(SPA_META_Header),
                        SPA_PARAM_META_size, SPA_POD_Int(sizeof(struct spa_meta_header)));
                break;
 
        default:
                return -ENOENT;
        }
 
        if (spa_pod_filter(&b, &result.param, param, filter) < 0)
                goto next;
 
        spa_node_emit_result(&d->hooks, seq, 0, SPA_RESULT_TYPE_NODE_PARAMS, &result);
 
        if (++count != num)
                goto next;
 
        return 0;
}
 
static int port_set_format(void *object, enum spa_direction direction, uint32_t port_id,
                           uint32_t flags, const struct spa_pod *format)
{
        struct data *d = object;
        Uint32 sdl_format;
        void *dest;
 
        if (format == NULL) {
                spa_zero(d->format);
                SDL_DestroyTexture(d->texture);
                d->texture = NULL;
        } else {
                spa_debug_format(0, NULL, format);
 
                spa_format_video_raw_parse(format, &d->format);
 
                sdl_format = id_to_sdl_format(d->format.format);
                if (sdl_format == SDL_PIXELFORMAT_UNKNOWN)
                        return -EINVAL;
                if (d->format.size.width == 0 ||
                    d->format.size.height == 0)
                        return -EINVAL;
 
                d->texture = SDL_CreateTexture(d->renderer,
                                               sdl_format,
                                               SDL_TEXTUREACCESS_STREAMING,
                                               d->format.size.width,
                                               d->format.size.height);
                SDL_LockTexture(d->texture, NULL, &dest, &d->stride);
                SDL_UnlockTexture(d->texture);
        }
 
        d->info.change_mask = SPA_PORT_CHANGE_MASK_PARAMS;
        if (format) {
                d->params[1] = SPA_PARAM_INFO(SPA_PARAM_Format, SPA_PARAM_INFO_READWRITE);
                d->params[2] = SPA_PARAM_INFO(SPA_PARAM_Buffers, SPA_PARAM_INFO_READ);
        } else {
                d->params[1] = SPA_PARAM_INFO(SPA_PARAM_Format, SPA_PARAM_INFO_WRITE);
                d->params[2] = SPA_PARAM_INFO(SPA_PARAM_Buffers, 0);
        }
        spa_node_emit_port_info(&d->hooks, SPA_DIRECTION_INPUT, 0, &d->info);
 
        return 0;
}
 
static int impl_port_set_param(void *object,
                               enum spa_direction direction, uint32_t port_id,
                               uint32_t id, uint32_t flags,
                               const struct spa_pod *param)
{
        if (id == SPA_PARAM_Format) {
                return port_set_format(object, direction, port_id, flags, param);
        }
        else
                return -ENOENT;
}
 
static int impl_port_use_buffers(void *object,
                enum spa_direction direction, uint32_t port_id,
                uint32_t flags, struct spa_buffer **buffers, uint32_t n_buffers)
{
        struct data *d = object;
        uint32_t i;
 
        if (n_buffers > MAX_BUFFERS)
                return -ENOSPC;
 
        for (i = 0; i < n_buffers; i++)
                d->buffers[i] = buffers[i];
        d->n_buffers = n_buffers;
        return 0;
}
 
static int do_render(struct spa_loop *loop, bool async, uint32_t seq,
                     const void *_data, size_t size, void *user_data)
{
        struct data *d = user_data;
        struct spa_buffer *buf;
        uint8_t *map;
        void *sdata, *ddata;
        int sstride, dstride, ostride;
        uint32_t i;
        uint8_t *src, *dst;
 
        buf = d->buffers[d->io->buffer_id];
 
        if (buf->datas[0].type == SPA_DATA_MemFd ||
            buf->datas[0].type == SPA_DATA_DmaBuf) {
                map = mmap(NULL, buf->datas[0].maxsize + buf->datas[0].mapoffset, PROT_READ,
                           MAP_PRIVATE, buf->datas[0].fd, 0);
                sdata = SPA_PTROFF(map, buf->datas[0].mapoffset, uint8_t);
        } else if (buf->datas[0].type == SPA_DATA_MemPtr) {
                map = NULL;
                sdata = buf->datas[0].data;
        } else
                return -EINVAL;
 
        if (SDL_LockTexture(d->texture, NULL, &ddata, &dstride) < 0) {
                fprintf(stderr, "Couldn't lock texture: %s\n", SDL_GetError());
                return -EIO;
        }
        sstride = buf->datas[0].chunk->stride;
        ostride = SPA_MIN(sstride, dstride);
 
        src = sdata;
        dst = ddata;
        for (i = 0; i < d->format.size.height; i++) {
                memcpy(dst, src, ostride);
                src += sstride;
                dst += dstride;
        }
        SDL_UnlockTexture(d->texture);
 
        SDL_RenderClear(d->renderer);
        SDL_RenderCopy(d->renderer, d->texture, NULL, NULL);
        SDL_RenderPresent(d->renderer);
 
        if (map)
                munmap(map, buf->datas[0].maxsize + buf->datas[0].mapoffset);
 
        return 0;
}
 
static int impl_node_process(void *object)
{
        struct data *d = object;
        int res;
 
        if ((res = pw_loop_invoke(pw_main_loop_get_loop(d->loop), do_render,
                                  SPA_ID_INVALID, NULL, 0, true, d)) < 0)
                return res;
 
        handle_events(d);
 
        d->io->status = SPA_STATUS_NEED_DATA;
 
        return SPA_STATUS_NEED_DATA;
}
 
static const struct spa_node_methods impl_node = {
        SPA_VERSION_NODE_METHODS,
        .add_listener = impl_add_listener,
        .set_callbacks = impl_set_callbacks,
        .set_io = impl_set_io,
        .send_command = impl_send_command,
        .port_set_io = impl_port_set_io,
        .port_enum_params = impl_port_enum_params,
        .port_set_param = impl_port_set_param,
        .port_use_buffers = impl_port_use_buffers,
        .process = impl_node_process,
};
 
static int make_nodes(struct data *data)
{
        struct pw_properties *props;
 
        data->impl_node.iface = SPA_INTERFACE_INIT(
                        SPA_TYPE_INTERFACE_Node,
                        SPA_VERSION_NODE,
                        &impl_node, data);
 
        data->info = SPA_PORT_INFO_INIT();
        data->info.change_mask =
                SPA_PORT_CHANGE_MASK_FLAGS |
                SPA_PORT_CHANGE_MASK_PARAMS;
        data->info.flags = 0;
        data->params[0] = SPA_PARAM_INFO(SPA_PARAM_EnumFormat, SPA_PARAM_INFO_READ);
        data->params[1] = SPA_PARAM_INFO(SPA_PARAM_Format, SPA_PARAM_INFO_WRITE);
        data->params[2] = SPA_PARAM_INFO(SPA_PARAM_Buffers, 0);
        data->params[3] = SPA_PARAM_INFO(SPA_PARAM_Meta, SPA_PARAM_INFO_READ);
        data->info.params = data->params;
        data->info.n_params = SPA_N_ELEMENTS(data->params);
 
        data->in = pw_core_export(data->core,
                        SPA_TYPE_INTERFACE_Node,
                        NULL,
                        &data->impl_node,
                        0);
 
        props = pw_properties_new(
                        SPA_KEY_LIBRARY_NAME, "v4l2/libspa-v4l2",
                        SPA_KEY_FACTORY_NAME, SPA_NAME_API_V4L2_SOURCE,
                        NULL);
 
        data->out = pw_core_create_object(data->core,
                        "spa-node-factory",
                        PW_TYPE_INTERFACE_Node,
                        PW_VERSION_NODE,
                        &props->dict, 0);
 
 
        while (true) {
 
                if (pw_proxy_get_bound_id(data->out) != SPA_ID_INVALID &&
                    pw_proxy_get_bound_id(data->in) != SPA_ID_INVALID)
                        break;
 
                pw_loop_iterate(pw_main_loop_get_loop(data->loop), -1);
        }
 
        pw_properties_clear(props);
 
        pw_properties_setf(props,
                        PW_KEY_LINK_OUTPUT_NODE, "%d", pw_proxy_get_bound_id(data->out));
        pw_properties_setf(props,
                        PW_KEY_LINK_INPUT_NODE, "%d", pw_proxy_get_bound_id(data->in));
 
        data->link = pw_core_create_object(data->core,
                        "link-factory",
                        PW_TYPE_INTERFACE_Link,
                        PW_VERSION_LINK,
                        &props->dict, 0);
 
        pw_properties_free(props);
 
        return 0;
}
 
int main(int argc, char *argv[])
{
        struct data data = { 0, };
 
        pw_init(&argc, &argv);
 
        data.loop = pw_main_loop_new(NULL);
        data.context = pw_context_new(
                        pw_main_loop_get_loop(data.loop),
                        pw_properties_new(
                                PW_KEY_CORE_DAEMON, "false",
                                NULL), 0);
 
        spa_hook_list_init(&data.hooks);
 
        pw_context_load_module(data.context, "libpipewire-module-spa-node-factory", NULL, NULL);
        pw_context_load_module(data.context, "libpipewire-module-link-factory", NULL, NULL);
 
        if (SDL_Init(SDL_INIT_VIDEO) < 0) {
                printf("can't initialize SDL: %s\n", SDL_GetError());
                return -1;
        }
 
        if (SDL_CreateWindowAndRenderer
            (WIDTH, HEIGHT, SDL_WINDOW_RESIZABLE, &data.window, &data.renderer)) {
                printf("can't create window: %s\n", SDL_GetError());
                return -1;
        }
 
        data.core = pw_context_connect_self(data.context, NULL, 0);
        if (data.core == NULL) {
                printf("can't connect to core: %m\n");
                return -1;
        }
 
        make_nodes(&data);
 
        pw_main_loop_run(data.loop);
 
        pw_proxy_destroy(data.link);
        pw_proxy_destroy(data.in);
        pw_proxy_destroy(data.out);
        pw_context_destroy(data.context);
        pw_main_loop_destroy(data.loop);
        pw_deinit();
 
        return 0;
}