Paint: save functionality

The pathname is fixed right now, this GUI isn't there yet to show a
modal with a textfield. Better rename the saved file if you intend to
save several in one session. Oh wait, you can't rename a file yet!

Relatedly, fixes a memory leak when writing to a file on an ext2 file
system. I found it because at first I wrote the saved image pixel by
pixel... Which took several seconds, and made the kernel abort due to
being out of memory.

kernel/src/misc/ext2.c

@@ -290,6 +290,7 @@ uint32_t ext2_append(ext2_fs_t* fs, uint32_t inode, uint8_t* data, uint32_t size
     in->size_lower += size;
     update_inode(fs, inode, in);
     kfree(tmp);
+    kfree(in);
 
     return size;
 }

modules/Makefile

@@ -19,15 +19,13 @@ install-headers:
 clean:
 	$(info [modules] cleaning up)
 	@rm -f */*.o
-	@find . -executable -type f -delete
 
-# TODO: every module depends on every other, a change in one rebuilds all of them
 $(MODS): $(OBJS) $(LIB_DEPS) src/start.o
-	$(info [modules] $(notdir $@))
 	@mkdir -p $(TARGETROOT)
 	@$(LD) src/start.o src/$(@F).o -o $@ $(LDFLAGS) $(LIBS)
 
 %.o: %.c
+	$(info [modules] $(notdir $(basename $@)))
 	@$(CC) -c $< -o $@ $(CFLAGS)
 
 %.o: %.S

modules/src/background.c

@@ -17,15 +17,15 @@ int main() {
         uint32_t n_pixels = win->fb.width*win->fb.height;
         uint8_t* bg = malloc(n_pixels * 3);
         fread(bg, 3, n_pixels, wp);
-        snow_draw_rgb(win->fb, bg, 0, 0, win->fb.width, win->fb.height, 0x000000);
+        snow_draw_rgb(win->fb, bg, 0, 0, win->fb.width, win->fb.height);
         free(bg);
         fclose(wp);
     } else {
         snow_draw_rect(win->fb, 0, 0, scr.width, scr.height, 0x9AC4F8);
     }
 
     snow_draw_rect(win->fb, 0, 0, win->fb.width, 22, 0x303030);
-    snow_draw_string(win->fb, "Snowflake OS 0.5", 3, 3, 0x00FFFFFF);
+    snow_draw_string(win->fb, "Snowflake OS 0.6", 3, 3, 0x00FFFFFF);
     snow_render_window(win);
 
     while (true) {
@@ -53,7 +53,7 @@ int main() {
         };
 
         snow_draw_rect(win->fb, 0, 0, win->fb.width, 22, 0x303030);
-        snow_draw_string(win->fb, "Snowflake OS 0.5", 3, 3, 0x00FFFFFF);
+        snow_draw_string(win->fb, "Snowflake OS 0.6", 3, 3, 0x00FFFFFF);
         snow_draw_string(win->fb, time_text, x, y, 0xFFFFFF);
         snow_render_window_partial(win, redraw);
 

modules/src/paint.c

@@ -6,7 +6,11 @@
 #include <string.h>
 
 // callbacks
-void on_clear_clicked(button_t* button);
+void on_clear_clicked();
+void on_save_clicked();
+
+bool load(const char* path, uint32_t w, uint32_t h);
+void save();
 
 const uint32_t width = 550;
 const uint32_t height = 320;
@@ -36,24 +40,29 @@ int main(int argc, char* argv[]) {
     ui_app_t paint = ui_app_new(win, fd ? icon : NULL);
 
     vbox_t* vbox = vbox_new();
-    ui_set_root(paint, (widget_t*) vbox);
+    ui_set_root(paint, W(vbox));
 
     hbox_t* menu = hbox_new();
     menu->widget.flags &= ~UI_EXPAND_VERTICAL;
     menu->widget.bounds.h = 20;
-    vbox_add(vbox, (widget_t*) menu);
+    vbox_add(vbox, W(menu));
 
     canvas = canvas_new();
-    vbox_add(vbox, (widget_t*) canvas);
+    canvas->color = colors[0];
+    vbox_add(vbox, W(canvas));
 
     for (uint32_t i = 0; i < sizeof(colors)/sizeof(colors[0]); i++) {
         color_button_t* cbutton = color_button_new(colors[i], &canvas->color);
-        hbox_add(menu, (widget_t*) cbutton);
+        hbox_add(menu, W(cbutton));
     }
 
     button_t* button = button_new("Clear");
     button->on_click = on_clear_clicked;
-    hbox_add(menu, (widget_t*) button);
+    hbox_add(menu, W(button));
+
+    button_t* save_button = button_new("Save");
+    save_button->on_click = on_save_clicked;
+    hbox_add(menu, W(save_button));
 
     ui_draw(paint);
     snow_render_window(win);
@@ -64,22 +73,10 @@ int main(int argc, char* argv[]) {
         uint32_t w = strtol(argv[2], NULL, 10);
         uint32_t h = strtol(argv[3], NULL, 10);
 
-        FILE* fd = fopen(fname, "r");
-
-        if (fd) {
-            uint8_t* buf = malloc(w*h*3);
-
-            if ((uint32_t) fread(buf, 3, w*h, fd) < w*h) {
-                printf("paint: file smaller than expected\n");
-            } else {
-                rect_t r = ui_get_absolute_bounds(W(canvas));
-                snow_draw_rgb(win->fb, buf, r.x, r.y, w, h, 0);
-            }
-
-            free(buf);
-            fclose(fd);
+        if (load(argv[1], w, h)) {
+            printf("paint: opened '%s'\n", fname);
         } else {
-            printf("paint: failed to open '%s'\n", fname);
+            printf("paint: failed to load '%s'\n", fname);
         }
     }
 
@@ -105,8 +102,70 @@ int main(int argc, char* argv[]) {
     return 0;
 }
 
-void on_clear_clicked(button_t* button) {
-    (void) button;
-
+void on_clear_clicked() {
     canvas->needs_clearing = true;
+}
+
+void on_save_clicked() {
+    save(NULL);
+}
+
+bool load(const char* path, uint32_t w, uint32_t h) {
+    FILE* fd = fopen(path, "r");
+
+    if (!fd) {
+        return false;
+    }
+
+    uint8_t* buf = malloc(w*h*3);
+
+    if ((uint32_t) fread(buf, 3, w*h, fd) < w*h) {
+        free(buf);
+        return false;
+    } else {
+        rect_t r = ui_get_absolute_bounds(W(canvas));
+        snow_draw_rgb(win->fb, buf, r.x, r.y, w, h);
+    }
+
+    free(buf);
+    fclose(fd);
+
+    return true;
+}
+
+void save() {
+    char fname[256] = "drawing_";
+    rect_t r = ui_get_absolute_bounds(W(canvas));
+
+    itoa(r.w, fname+strlen(fname), 10);
+    strcat(fname, "x");
+    itoa(r.h, fname+strlen(fname), 10);
+    strcat(fname, ".rgb");
+
+    printf("paint: saving to '%s'.\n", fname);
+
+    FILE* fd = fopen(fname, "w");
+
+    if (!fd) {
+        printf("paint: failed to open output file '%s'\n", fname);
+        return;
+    }
+
+    uint8_t* buf = malloc(r.w*r.h*3);
+
+    /* Convert from RGBA to RGB */
+    for (int y = r.y; y < r.y+r.h; y++) {
+        for (int x = r.x; x < r.x+r.w; x++) {
+            uint32_t px = ((uint32_t*) win->fb.address)[y*win->fb.pitch/4 + x];
+            uint8_t* pixbuf = (uint8_t*) &px;
+            uint32_t idx = (y - r.y)*3*r.w + (x - r.x)*3;
+            buf[idx] = pixbuf[2];
+            buf[idx + 1] = pixbuf[1];
+            buf[idx + 2] = pixbuf[0];
+        }
+    }
+
+    fwrite(buf, 3, r.w*r.h, fd);
+    free(buf);
+    fclose(fd);
 }

snow/include/snow.h

@@ -36,7 +36,8 @@ void snow_draw_line(fb_t fb, int x0, int y0, int x1, int y1, uint32_t col);
 void snow_draw_border(fb_t fb, int x, int y, int w, int h, uint32_t col);
 void snow_draw_character(fb_t fb, char c, int x, int y, uint32_t col);
 void snow_draw_string(fb_t fb, char* str, int x, int y, uint32_t col);
-void snow_draw_rgb(fb_t fb, uint8_t* rgb, int x, int y, int w, int h, uint32_t mask);
+void snow_draw_rgb(fb_t fb, uint8_t* rgb, int x, int y, int w, int h);
+void snow_draw_rgb_masked(fb_t fb, uint8_t* rgb, int x, int y, int w, int h, uint32_t mask);
 
 // GUI functions
 window_t* snow_open_window(char* title, int width, int height, uint32_t flags);

snow/src/graphics.c

@@ -170,7 +170,17 @@ void snow_draw_string(fb_t fb, char* str, int x, int y, uint32_t col) {
     }
 }
 
-void snow_draw_rgb(fb_t fb, uint8_t* rgb, int x, int y, int w, int h, uint32_t mask) {
+void snow_draw_rgb(fb_t fb, uint8_t* rgb, int x, int y, int w, int h) {
+    for (int i = 0, c = 0; i < h; i++) {
+        for (int j = 0; j < w; j++, c += 3) {
+            uint32_t col = rgb[c] << 16 | rgb[c+1] << 8 | rgb[c+2];
+
+            snow_draw_pixel(fb, x + j, y + i, col);
+        }
+    }
+}
+
+void snow_draw_rgb_masked(fb_t fb, uint8_t* rgb, int x, int y, int w, int h, uint32_t mask) {
     for (int i = 0, c = 0; i < h; i++) {
         for (int j = 0; j < w; j++, c += 3) {
             uint32_t col = rgb[c] << 16 | rgb[c+1] << 8 | rgb[c+2];

ui/src/titlebar.c

@@ -10,7 +10,7 @@ void titlebar_on_draw(titlebar_t* tb, fb_t fb) {
     snow_draw_rect(fb, r.x, r.y, r.w, r.h, 0x303030);
 
     if (tb->icon) {
-        snow_draw_rgb(fb, tb->icon, r.x+2, r.y+2, 16, 16, 0xFFFFFF);
+        snow_draw_rgb_masked(fb, tb->icon, r.x+2, r.y+2, 16, 16, 0xFFFFFF);
         snow_draw_string(fb, tb->title, r.x+16+5, r.y+3, 0xFFFFFF);
     } else {
         snow_draw_string(fb, tb->title, r.x+3, r.y+3, 0xFFFFFF);