[sdl] sdl backend stub (runs SDL_Init and friends)

Makefile

@@ -1,5 +1,7 @@
 cc = clang
 
+sdl_ldflags = $(shell pkg-config SDL2_ttf sdl2 --libs)
+
 cflags = -g -O0 -pthread \
 	-Wall \
 	-Wshadow  \
@@ -25,6 +27,6 @@ gen:
 	racket scripts/enum.rkt src _build
 
 ${test_bin}: ${srcs} ${hdrs}
-	${cc} ${cflags} ${srcs} -o ${test_bin}
+	${cc} ${cflags} ${srcs} ${sdl_ldflags} -o ${test_bin}
 
 .PHONY: all clean gen

src/backend.h

@@ -10,8 +10,10 @@ struct ax_font_h;
 
 extern const char* ax__backend_impl_name;
 
-struct ax_backend* ax__backend_new(
-    struct rgn* init_rgn);
+int ax__backend_new(
+    struct rgn* init_rgn,
+    struct ax_backend** out_bac,
+    const char** out_err);
 
 const char* ax__backend_get_error(
     struct ax_backend* bac);

src/backend/sdl.c

@@ -1,20 +1,53 @@
 #include "../backend.h"
 #include "../util/region.h"
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_ttf.h>
 
 struct ax_backend {
 };
 
 const char* ax__backend_impl_name = "SDL";
 
-struct ax_backend* ax__backend_new(
-    struct rgn* init_rgn)
+static void shutdown_backend(struct ax_backend* bac);
+
+int ax__backend_new(
+    struct rgn* init_rgn,
+    struct ax_backend** out_bac,
+    const char** out_err)
 {
+    const char* err;
+    if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER) != 0) {
+        err = SDL_GetError();
+        goto fail;
+    }
+    if (TTF_Init() != 0) {
+        err = TTF_GetError();
+        goto fail;
+    }
+
     struct ax_backend* bac = ralloc_typed(init_rgn, struct ax_backend, 1);
-    return bac;
+    rgn_pin(init_rgn, bac, (void*) shutdown_backend);
+
+    if (out_bac != NULL) {
+        *out_bac = bac;
+    }
+    return 0;
+
+fail:
+    if (out_err != NULL) {
+        *out_err = err;
+    }
+    return 1;
 }
 
-const char* ax__backend_get_error(
-    struct ax_backend* bac)
+static void shutdown_backend(struct ax_backend* bac)
+{
+    // printf("bye, from SDL\n");
+    TTF_Quit();
+    SDL_Quit();
+}
+
+const char* ax__backend_get_error(struct ax_backend* bac)
 {
     (void) bac;
     return NULL;

src/ctxt.h

@@ -43,5 +43,3 @@ static inline void ax__set_error(struct ax_ctxt* ax, const char* text)
 {
     strcpy(ax__make_error_buf(ax, strlen(text) + 1), text);
 }
-
-struct ax_backend* ax__backend(struct ax_ctxt* ax);

src/ctxt/ctxt.c

@@ -49,7 +49,12 @@ void ax__ctxt_init(struct ax_ctxt* ax, struct rgn* init_rgn)
     ax->thmb = NULL;
     ax->sel_theme = NULL;
 
-    ax->bac = NULL;
+    const char* err;
+    if (ax__backend_new(init_rgn, &ax->bac, &err) != 0) {
+        ASSERT(0, "initializing %s backend failed: %s",
+               ax__backend_impl_name,
+               err);
+    }
 }
 
 void ax__ctxt_cleanup(struct ax_ctxt* ax)
@@ -58,20 +63,6 @@ void ax__ctxt_cleanup(struct ax_ctxt* ax)
     rgn_cleanup(&ax->err_rgn);
 }
 
-struct ax_backend* ax__backend(struct ax_ctxt* ax)
-{
-    if (ax->bac == NULL) {
-        struct rgn msg_rgn;
-        rgn_init(&msg_rgn, SMALL);
-        ax_log(ax, rsprintf(&msg_rgn, "initializing `%s' backend",
-                            ax__backend_impl_name));
-        rgn_cleanup(&msg_rgn);
-
-        ax->bac = ax__backend_new(ax->init_rgn);
-    }
-    return ax->bac;
-}
-
 /* -----------------------------------------------------------------------------
  * API functions :: logging
  * -------------------------------------------------------------------------- */
@@ -106,13 +97,9 @@ void ax_begin_theme(struct ax_ctxt* ax)
 void ax_end_theme(struct ax_ctxt* ax, struct ax_theme** out_thm)
 {
     ASSERT(ax->thmb != NULL, "`ax_end_theme' called while not building a theme");
-
     struct ax_theme* thm;
     ax__theme_builder_finish(ax->thmb, ax->init_rgn, &thm);
     rgn_clear(&ax->thmb_rgn);
-
-    (void) ax__backend(ax); // TODO: tell backend to load this theme
-
     if (out_thm != NULL) {
         *out_thm = thm;
     }