wlroots/render/drm_format_set.c

#include <assert.h>
#include <drm_fourcc.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <wlr/render/drm_format_set.h>
#include <wlr/util/log.h>
#include "render/drm_format_set.h"

void wlr_drm_format_finish(struct wlr_drm_format *format) {
	if (!format) {
		return;
	}

	free(format->modifiers);
}

void wlr_drm_format_set_finish(struct wlr_drm_format_set *set) {
	for (size_t i = 0; i < set->len; ++i) {
		wlr_drm_format_finish(set->formats[i]);
		free(set->formats[i]);
	}
	free(set->formats);

	set->len = 0;
	set->capacity = 0;
	set->formats = NULL;
}

static struct wlr_drm_format **format_set_get_ref(struct wlr_drm_format_set *set,
		uint32_t format) {
	for (size_t i = 0; i < set->len; ++i) {
		if (set->formats[i]->format == format) {
			return &set->formats[i];
		}
	}

	return NULL;
}

const struct wlr_drm_format *wlr_drm_format_set_get(
		const struct wlr_drm_format_set *set, uint32_t format) {
	struct wlr_drm_format **ptr =
		format_set_get_ref((struct wlr_drm_format_set *)set, format);
	return ptr ? *ptr : NULL;
}

bool wlr_drm_format_set_has(const struct wlr_drm_format_set *set,
		uint32_t format, uint64_t modifier) {
	const struct wlr_drm_format *fmt = wlr_drm_format_set_get(set, format);
	if (!fmt) {
		return false;
	}
	return wlr_drm_format_has(fmt, modifier);
}

bool wlr_drm_format_set_add(struct wlr_drm_format_set *set, uint32_t format,
		uint64_t modifier) {
	assert(format != DRM_FORMAT_INVALID);

	struct wlr_drm_format **ptr = format_set_get_ref(set, format);
	if (ptr) {
		return wlr_drm_format_add(*ptr, modifier);
	}

	struct wlr_drm_format *fmt = calloc(1, sizeof(*fmt));
	if (!fmt) {
		return false;
	}

	wlr_drm_format_init(fmt, format);
	if (!wlr_drm_format_add(fmt, modifier)) {
		wlr_drm_format_finish(fmt);
		return false;
	}

	if (set->len == set->capacity) {
		size_t new = set->capacity ? set->capacity * 2 : 4;

		struct wlr_drm_format **tmp = realloc(set->formats,
			sizeof(set->formats[0]) * new);
		if (!tmp) {
			wlr_log_errno(WLR_ERROR, "Allocation failed");
			free(fmt);
			return false;
		}

		set->capacity = new;
		set->formats = tmp;
	}

	set->formats[set->len++] = fmt;
	return true;
}

void wlr_drm_format_init(struct wlr_drm_format *fmt, uint32_t format) {
	memset(fmt, 0, sizeof(*fmt));
	fmt->format = format;
}

bool wlr_drm_format_has(const struct wlr_drm_format *fmt, uint64_t modifier) {
	for (size_t i = 0; i < fmt->len; ++i) {
		if (fmt->modifiers[i] == modifier) {
			return true;
		}
	}
	return false;
}

bool wlr_drm_format_add(struct wlr_drm_format *fmt, uint64_t modifier) {
	if (wlr_drm_format_has(fmt, modifier)) {
		return true;
	}

	if (fmt->len == fmt->capacity) {
		size_t capacity = fmt->capacity ? fmt->capacity * 2 : 4;

		uint64_t *new_modifiers = realloc(fmt->modifiers, sizeof(*fmt->modifiers) * capacity);
		if (!new_modifiers) {
			wlr_log_errno(WLR_ERROR, "Allocation failed");
			return false;
		}

		fmt->capacity = capacity;
		fmt->modifiers = new_modifiers;
	}

	fmt->modifiers[fmt->len++] = modifier;
	return true;
}

struct wlr_drm_format *wlr_drm_format_dup(const struct wlr_drm_format *format) {
	assert(format->len <= format->capacity);

	uint64_t *modifiers = malloc(sizeof(*format->modifiers) * format->capacity);
	if (!modifiers) {
		return NULL;
	}

	memcpy(modifiers, format->modifiers, sizeof(*format->modifiers) * format->len);

	struct wlr_drm_format *dst = calloc(1, sizeof(*dst));
	if (!dst) {
		return NULL;
	}

	dst->capacity = format->capacity;
	dst->len = format->len;
	dst->modifiers = modifiers;

	return dst;
}

bool wlr_drm_format_set_copy(struct wlr_drm_format_set *dst, const struct wlr_drm_format_set *src) {
	struct wlr_drm_format **formats = malloc(src->len * sizeof(formats[0]));
	if (formats == NULL) {
		return false;
	}

	struct wlr_drm_format_set out = {
		.len = 0,
		.capacity = src->len,
		.formats = formats,
	};

	size_t i;
	for (i = 0; i < src->len; i++) {
		out.formats[out.len] = wlr_drm_format_dup(src->formats[i]);
		if (out.formats[out.len] == NULL) {
			wlr_drm_format_set_finish(&out);
			return false;
		}
		out.len++;
	}

	*dst = out;

	return true;
}

struct wlr_drm_format *wlr_drm_format_intersect(
		const struct wlr_drm_format *a, const struct wlr_drm_format *b) {
	assert(a->format == b->format);

	size_t capacity = a->len < b->len ? a->len : b->len;
	uint64_t *modifiers = malloc(sizeof(*modifiers) * capacity);
	if (!modifiers) {
		return false;
	}

	struct wlr_drm_format fmt = {
		.capacity = capacity,
		.len = 0,
		.modifiers = modifiers,
		.format = a->format,
	};

	for (size_t i = 0; i < a->len; i++) {
		for (size_t j = 0; j < b->len; j++) {
			if (a->modifiers[i] == b->modifiers[j]) {
				assert(fmt.len < fmt.capacity);
				fmt.modifiers[fmt.len++] = a->modifiers[i];
				break;
			}
		}
	}

	// If the intersection is empty, then the formats aren't compatible with
	// each other.
	if (fmt.len == 0) {
		wlr_drm_format_finish(&fmt);
		return NULL;
	}

	struct wlr_drm_format *format = calloc(1, sizeof(*format));
	if (!format) {
		wlr_drm_format_finish(&fmt);
		return NULL;
	}
	*format = fmt;
	return format;
}

bool wlr_drm_format_set_intersect(struct wlr_drm_format_set *dst,
		const struct wlr_drm_format_set *a, const struct wlr_drm_format_set *b) {
	struct wlr_drm_format_set out = {0};
	out.capacity = a->len < b->len ? a->len : b->len;
	out.formats = calloc(out.capacity, sizeof(struct wlr_drm_format *));
	if (out.formats == NULL) {
		wlr_log_errno(WLR_ERROR, "Allocation failed");
		return false;
	}

	for (size_t i = 0; i < a->len; i++) {
		for (size_t j = 0; j < b->len; j++) {
			if (a->formats[i]->format == b->formats[j]->format) {
				// When the two formats have no common modifier, keep
				// intersecting the rest of the formats: they may be compatible
				// with each other
				struct wlr_drm_format *format =
					wlr_drm_format_intersect(a->formats[i], b->formats[j]);
				if (format != NULL) {
					out.formats[out.len] = format;
					out.len++;
				}
				break;
			}
		}
	}

	if (out.len == 0) {
		wlr_drm_format_set_finish(&out);
		return false;
	}

	wlr_drm_format_set_finish(dst);
	*dst = out;
	return true;
}

static bool drm_format_set_extend(struct wlr_drm_format_set *dst,
		const struct wlr_drm_format_set *src) {
	for (size_t i = 0; i < src->len; i++) {
		struct wlr_drm_format *format = src->formats[i];
		for (size_t j = 0; j < format->len; j++) {
			if (!wlr_drm_format_set_add(dst, format->format, format->modifiers[j])) {
				wlr_log_errno(WLR_ERROR, "Adding format/modifier to set failed");
				return false;
			}
		}
	}

	return true;
}

bool wlr_drm_format_set_union(struct wlr_drm_format_set *dst,
		const struct wlr_drm_format_set *a, const struct wlr_drm_format_set *b) {
	struct wlr_drm_format_set out = {0};
	out.capacity = a->len + b->len;
	out.formats = calloc(out.capacity, sizeof(struct wlr_drm_format *));
	if (out.formats == NULL) {
		wlr_log_errno(WLR_ERROR, "Allocation failed");
		return false;
	}

	// Add both a and b sets into out
	if (!drm_format_set_extend(&out, a)) {
		return false;
	}
	if (!drm_format_set_extend(&out, b)) {
		return false;
	}

	wlr_drm_format_set_finish(dst);
	*dst = out;

	return true;
}