[systemd-devel] [RFC 07/12] gfx: add graphics layer

[Lennart Poettering]

On Wed, 27.11.13 19:48, David Herrmann (dh.herrmann at gmail.com) wrote:

> +typedef struct gfx_config_pipe gfx_config_pipe;
> +typedef struct gfx_connector gfx_connector;
> +typedef struct gfx_encoder gfx_encoder;
> +
> +/* clock-wise framebuffer rotation */
> +enum {
> +        GFX_ROTATE_0,
> +        GFX_ROTATE_90,
> +        GFX_ROTATE_180,
> +        GFX_ROTATE_270,
> +};
> +
> +struct gfx_config_pipe {
> +        unsigned int config_id;
> +        char **connectors;
> +        char *mode;
> +        unsigned int rotate;
> +
> +        unsigned int disable : 1;

C99 bool plz! (here and everywhere else...)

> +        memset(handles, 0, sizeof(handles));
> +        memset(strides, 0, sizeof(strides));
> +        memset(offsets, 0, sizeof(offsets));

zero(handles) is so much nicer... (here and everywhere...)

> +static int gfx_pipe_new(sd_gfx_pipe **out, sd_gfx_card *card, drmModeCrtc *crtc, unsigned int connector_count) {
> +        sd_gfx_pipe *pipe;
> +        int r;
> +
> +        pipe = calloc(1, sizeof(*pipe));
> +        if (!pipe)
> +                return log_oom();
> +
> +        pipe->ref = 1;
> +        pipe->card = card;
> +        pipe->id = card->pipe_ids;
> +        pipe->crtc_id = crtc->crtc_id;
> +        pipe->page_flip_cnt = 1;
> +
> +        pipe->connectors = calloc(connector_count, sizeof(*pipe->connectors));
> +        if (!pipe->connectors) {
> +                r = log_oom();
> +                goto err_pipe;
> +        }
> +
> +        pipe->want_connectors = calloc(connector_count, sizeof(*pipe->want_connectors));
> +        if (!pipe->want_connectors) {
> +                r = log_oom();
> +                goto err_connectors;
> +        }
> +
> +        pipe->connector_ids = calloc(connector_count, sizeof(*pipe->connector_ids));
> +        if (!pipe->connector_ids) {
> +                r = log_oom();
> +                goto err_want_connectors;
> +        }
> +
> +        pipe->want_connector_ids = calloc(connector_count, sizeof(*pipe->want_connector_ids));
> +        if (!pipe->want_connector_ids) {
> +                r = log_oom();
> +                goto err_connector_ids;
> +        }
> +
> +        r = gfx_plane_new_primary(&pipe->primary, pipe);
> +        if (r < 0)
> +                goto err_want_connector_ids;
> +
> +        gfx_pipe_refresh(pipe, crtc);
> +
> +        *out = pipe;
> +        return 0;
> +
> +err_want_connector_ids:
> +        free(pipe->want_connector_ids);
> +err_connector_ids:
> +        free(pipe->connector_ids);
> +err_want_connectors:
> +        free(pipe->want_connectors);
> +err_connectors:
> +        free(pipe->connectors);
> +err_pipe:
> +        free(pipe);
> +        return r;
> +}
> +

For clean-up code like this I usually find it nicer to simply have a
destructor function that is robust to destruct half-initialized objects
and then just invoke this here.

> +/* framebuffer */
> +
> +typedef void (*sd_gfx_fb_unlink_fn) (sd_gfx_fb *fb, void *fn_data);
> +typedef void (*sd_gfx_fb_unpin_fn) (sd_gfx_fb *fb, void *fn_data);

For the types that actually feel like primitive types (in contrast to
objects), we usually appended a libc style _t to our names. 

I can't really say much about the actual drm stuff going on here, just
my usualy whining about logging from lib code, C99 bools, zero()...

Lennart

-- 
Lennart Poettering, Red Hat