Bundle GUI variables in context struct

This allows to pass all variables easily between small functions.

1 files changed, 40 insertions, 25 deletions

diff --git a/gui.c b/gui.c
index 39e2b9a..cb26990 100644
--- a/gui.c
+++ b/gui.c
@@ -19,24 +19,39 @@
 
 #include <SDL2/SDL.h>
 #include <stdbool.h>
+#include <stdlib.h>
 #include <unistd.h>
 
 #include "xmpp.h"
 
 
-void gui_run(void) {
-
-	bool quit = false;
+struct GuiContext {
+	bool quit;
 	SDL_Event event;
 	SDL_Window* window;
 	SDL_Renderer* renderer;
 	SDL_Texture* texture;
 	uint32_t* pixels;
-	int xmpp_fd = -1;
+	int xmpp_fd;
+};
+
+
+struct GuiContext *init() {
+	struct GuiContext *ctx = malloc(sizeof(struct GuiContext));
+
+	ctx->quit = false;
+	ctx->xmpp_fd = -1;
+
+	return ctx;
+}
+
+void gui_run(void) {
+
+	struct GuiContext *ctx = init();
 
 	// init SDL2 and create window
 	SDL_Init(SDL_INIT_VIDEO);
-	window = SDL_CreateWindow("LimoX",
+	ctx->window = SDL_CreateWindow("LimoX",
 	    SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 640, 480,
 	    SDL_WINDOW_RESIZABLE
 	);
@@ -45,42 +60,42 @@ void gui_run(void) {
 	fprintf(stderr, "SDL2 video driver: %s\n", SDL_GetCurrentVideoDriver());
 
 	// create and initialize renderer, texture and pixel buffer
-	renderer = SDL_CreateRenderer(window, -1, 0);
-	texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_ARGB8888,
-	                            SDL_TEXTUREACCESS_STATIC, 640, 480);
-	pixels = malloc(sizeof(uint32_t) * 640 * 480);
-	memset(pixels, 255, 640 * 480 * sizeof(uint32_t));
+	ctx->renderer = SDL_CreateRenderer(ctx->window, -1, 0);
+	ctx->texture = SDL_CreateTexture(ctx->renderer, SDL_PIXELFORMAT_ARGB8888,
+	                                 SDL_TEXTUREACCESS_STATIC, 640, 480);
+	ctx->pixels = malloc(sizeof(uint32_t) * 640 * 480);
+	memset(ctx->pixels, 255, 640 * 480 * sizeof(uint32_t));
 
 	// handle failed window creation
-	if (window == NULL) {
+	if (ctx->window == NULL) {
 		fprintf(stderr, "Failed to create SDL2 window!\n");
 		return;
 	} else {
-		while (!quit) {
-			SDL_UpdateTexture(texture, NULL, pixels, 640 * sizeof(uint32_t));
-			SDL_WaitEvent(&event);
-			switch (event.type) {
+		while (!ctx->quit) {
+			SDL_UpdateTexture(ctx->texture, NULL, ctx->pixels, 640 * sizeof(uint32_t));
+			SDL_WaitEvent(&ctx->event);
+			switch (ctx->event.type) {
 			case SDL_QUIT:
-				quit = true;
+				ctx->quit = true;
 				break;
 			case SDL_MOUSEBUTTONDOWN:
-				if (xmpp_fd == -1) {
-					xmpp_fd = xmpp_connect();
+				if (ctx->xmpp_fd == -1) {
+					ctx->xmpp_fd = xmpp_connect();
 				} else {
-					close(xmpp_fd);
-					xmpp_fd = -1;
+					close(ctx->xmpp_fd);
+					ctx->xmpp_fd = -1;
 					printf("Closed XMPP connection.\n");
 				}
 				break;
 			}
-			SDL_RenderClear(renderer);
-			SDL_RenderCopy(renderer, texture, NULL, NULL);
-			SDL_RenderPresent(renderer);
+			SDL_RenderClear(ctx->renderer);
+			SDL_RenderCopy(ctx->renderer, ctx->texture, NULL, NULL);
+			SDL_RenderPresent(ctx->renderer);
 		}
-		SDL_DestroyWindow(window);
+		SDL_DestroyWindow(ctx->window);
 	}
 
-	free(pixels);
+	free(ctx->pixels);
 
 	// TODO this seems to end in memory access errors but ... why?
 	//SDL_DestroyTexture(texture);