1 #define _POSIX_C_SOURCE 200809
2 #include <assert.h>
3 #include <cairo.h>
4 #include <fcntl.h>
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include <sys/mman.h>
9 #include <unistd.h>
10 #include <wayland-client.h>
11 #include "pool-buffer.h"
12 
set_cloexec(int fd)13 static bool set_cloexec(int fd) {
14 	long flags = fcntl(fd, F_GETFD);
15 	if (flags == -1) {
16 		return false;
17 	}
18 
19 	if (fcntl(fd, F_SETFD, flags | FD_CLOEXEC) == -1) {
20 		return false;
21 	}
22 
23 	return true;
24 }
25 
create_pool_file(size_t size,char ** name)26 static int create_pool_file(size_t size, char **name) {
27 	static const char template[] = "sway-client-XXXXXX";
28 	const char *path = getenv("XDG_RUNTIME_DIR");
29 	if (path == NULL) {
30 		fprintf(stderr, "XDG_RUNTIME_DIR is not set\n");
31 		return -1;
32 	}
33 
34 	size_t name_size = strlen(template) + 1 + strlen(path) + 1;
35 	*name = malloc(name_size);
36 	if (*name == NULL) {
37 		fprintf(stderr, "allocation failed\n");
38 		return -1;
39 	}
40 	snprintf(*name, name_size, "%s/%s", path, template);
41 
42 	int fd = mkstemp(*name);
43 	if (fd < 0) {
44 		return -1;
45 	}
46 
47 	if (!set_cloexec(fd)) {
48 		close(fd);
49 		return -1;
50 	}
51 
52 	if (ftruncate(fd, size) < 0) {
53 		close(fd);
54 		return -1;
55 	}
56 
57 	return fd;
58 }
59 
create_buffer(struct pool_buffer * buf,struct wl_shm * shm,int32_t width,int32_t height,uint32_t format)60 bool create_buffer(struct pool_buffer *buf, struct wl_shm *shm,
61 		int32_t width, int32_t height, uint32_t format) {
62 	uint32_t stride = width * 4;
63 	size_t size = stride * height;
64 
65 	char *name;
66 	int fd = create_pool_file(size, &name);
67 	assert(fd != -1);
68 	void *data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
69 	struct wl_shm_pool *pool = wl_shm_create_pool(shm, fd, size);
70 	buf->buffer = wl_shm_pool_create_buffer(pool, 0,
71 			width, height, stride, format);
72 	wl_shm_pool_destroy(pool);
73 	close(fd);
74 	unlink(name);
75 	free(name);
76 	fd = -1;
77 
78 	buf->size = size;
79 	buf->data = data;
80 	buf->surface = cairo_image_surface_create_for_data(data,
81 			CAIRO_FORMAT_ARGB32, width, height, stride);
82 	buf->cairo = cairo_create(buf->surface);
83 	return true;
84 }
85 
destroy_buffer(struct pool_buffer * buffer)86 void destroy_buffer(struct pool_buffer *buffer) {
87 	if (buffer->buffer) {
88 		wl_buffer_destroy(buffer->buffer);
89 	}
90 	if (buffer->cairo) {
91 		cairo_destroy(buffer->cairo);
92 	}
93 	if (buffer->surface) {
94 		cairo_surface_destroy(buffer->surface);
95 	}
96 	if (buffer->data) {
97 		munmap(buffer->data, buffer->size);
98 	}
99 }
100