tooltip with address, byte value and strings

5 files changed, 157 insertions, 11 deletions

diff --git a/src/hash.h b/src/hash.h
index 238b15b..f9da7bb 100644
--- a/src/hash.h
+++ b/src/hash.h
@@ -3,7 +3,7 @@
 
 #include <stdint.h>
 
-static uint64_t fnv(uint8_t *data, size_t size) {
+static uint64_t fnv(const uint8_t *data, size_t size) {
 	uint64_t hash = 0xcbf29ce484222325;
 	for (size_t i = 0; i < size; i++) {
 		hash ^= data[i];
diff --git a/src/main.c b/src/main.c
index 4a80d21..e65459b 100644
--- a/src/main.c
+++ b/src/main.c
@@ -14,6 +14,7 @@
 #include "memory.h"
 #include "font.h"
 #include "menu.h"
+#include "tooltip.h"
 
 SDL_Window *window;
 SDL_Renderer *renderer;
@@ -34,6 +35,7 @@ static procfs_map *mappings = NULL;
 static int n_mappings = 0;
 
 static menu *current_menu = NULL;
+static tooltip current_tooltip = {0};
 
 static double get_scale() {
 	if (scale >= 1) {
@@ -307,6 +309,45 @@ static void update() {
 	} else {
 		mouse_held = false;
 	}
+
+	double x = mx, y = my;
+	absolute_pos(&x, &y);
+	uintptr_t addr = to_addr(x, y);
+	uintptr_t page_addr = addr - addr % PAGE_SIZE;
+	static uint8_t page_data[PAGE_SIZE];
+	if (read_mem(pages.fd, page_addr, page_data, PAGE_SIZE) == 0) {
+		uint8_t hover_byte = page_data[addr % PAGE_SIZE];
+		static char tooltip_buf[1024];
+		int n = snprintf(tooltip_buf, sizeof(tooltip_buf),
+			"%p\n0x%02x", addr, hover_byte
+		);
+		char *p = tooltip_buf + n;
+		if (hover_byte < 128 && hover_byte != 0) {
+			p = stpcpy(p, "\n\"");
+			int min, max;
+			for (min = addr % PAGE_SIZE; min > 0; min--) {
+				uint8_t next = page_data[min - 1];
+				if (next >= 128 || next == 0) break;
+			}
+			for (max = addr % PAGE_SIZE; max < PAGE_SIZE; max++) {
+				uint8_t cur = page_data[max];
+				if (cur >= 128 || cur == 0) break;
+			}
+			while (max - min > 64) {
+				if (max - addr % PAGE_SIZE > addr % PAGE_SIZE - min) {
+					max--;
+				} else {
+					min++;
+				}
+			}
+			memcpy(p, page_data + min, max - min);
+			p += max - min;
+			p = stpcpy(p, "\"");
+		}
+		set_tooltip_text(&current_tooltip, tooltip_buf);
+	} else {
+		set_tooltip_text(&current_tooltip, NULL);
+	}
 }
 
 static SDL_Texture *missing_texture();
@@ -377,6 +418,21 @@ static SDL_Texture *missing_texture() {
 	return tex;
 }
 
+static void show() {
+	SDL_GetWindowSize(window, &window_width, &window_height);
+	SDL_RenderClear(renderer);
+	show_pages();
+	SDL_RenderPresent(renderer);
+	if (current_menu) {
+		menu_render(current_menu);
+		hide_tooltip(&current_tooltip);
+	} else {
+		float mx, my;
+		SDL_GetMouseState(&mx, &my);
+		show_tooltip(&current_tooltip, mx, my);
+	}
+}
+
 static void main_loop() {
 	int last_time = 0, current_time = 0;
 	while (true) {
@@ -387,11 +443,7 @@ static void main_loop() {
 			}
 		}
 		update();
-		SDL_GetWindowSize(window, &window_width, &window_height);
-		SDL_RenderClear(renderer);
-		show_pages();
-		SDL_RenderPresent(renderer);
-		if (current_menu) menu_render(current_menu);
+		show();
 
 		last_time = current_time;
 		current_time = SDL_GetTicks();
diff --git a/src/menu.c b/src/menu.c
index 73b1dbd..caffa81 100644
--- a/src/menu.c
+++ b/src/menu.c
@@ -6,10 +6,10 @@
 #include "main.h"
 #include "menu.h"
 
-#define MENU_PADDING 4
+#define PADDING 4
 
 static int option_at(menu *m, int x, int y) {
-	float cur_y = MENU_PADDING;
+	float cur_y = PADDING;
 	for (int i = 0; i < m->count; i++) {
 		float tw, th;
 		must(SDL_GetTextureSize(m->textures[i], &tw, &th));
@@ -34,18 +34,19 @@ menu *create_menu(menu_entry *entries, int count, int x, int y) {
 	m->textures = calloc(count, sizeof(SDL_Texture *));
 	if (!m->textures) panic("out of memory");
 
-	int w = MENU_PADDING, h = MENU_PADDING;
+	int w = PADDING, h = PADDING;
 	for (int i = 0; i < count; i++) {
 		SDL_Color color = {0xff, 0xff, 0xff, 0xff};
 		SDL_Surface *text =
 			must(TTF_RenderText_Blended(font, m->entries[i].name, 0, color));
 		m->textures[i] = must(SDL_CreateTextureFromSurface(m->renderer, text));
+		SDL_DestroySurface(text);
 		float tw, th;
 		must(SDL_GetTextureSize(m->textures[i], &tw, &th));
 		w = SDL_max(w, tw);
 		h += th;
 	}
-	w += MENU_PADDING; h += MENU_PADDING;
+	w += PADDING; h += PADDING;
 	m->height = h;
 
 	int px, py;
@@ -122,7 +123,7 @@ void menu_render(menu *m) {
 
 	SDL_SetRenderDrawColor(m->renderer, 0x00, 0x00, 0x00, 0xff);
 	SDL_RenderClear(m->renderer);
-	float x = MENU_PADDING, y = MENU_PADDING - SDL_floor(m->scroll);
+	float x = PADDING, y = PADDING - SDL_floor(m->scroll);
 	for (int i = 0; i < m->count; i++) {
 		SDL_FRect dst;
 		dst.x = x;
diff --git a/src/tooltip.c b/src/tooltip.c
new file mode 100644
index 0000000..e900e40
--- /dev/null
+++ b/src/tooltip.c
@@ -0,0 +1,74 @@
+#include <SDL3/SDL.h>
+#include <SDL3_ttf/SDL_ttf.h>
+#include "panic.h"
+#include "font.h"
+#include "hash.h"
+#include "main.h"
+#include "tooltip.h"
+
+#define PADDING 4
+
+void set_tooltip_text(tooltip *t, const char *text) {
+	if (!t->window) {
+		t->window = must(SDL_CreatePopupWindow(window,
+			0, 0, 0, 0, SDL_WINDOW_TOOLTIP | SDL_WINDOW_BORDERLESS
+		));
+		t->renderer = must(SDL_CreateRenderer(t->window, NULL));
+	}
+	uint64_t hash = fnv(text, text ? strlen(text) : 0);
+	if (hash == t->hash) {
+		return;
+	}
+	t->hash = hash;
+	if (t->texture) {
+		SDL_DestroyTexture(t->texture);
+		t->texture = NULL;
+	}
+	if (!text) return;
+	SDL_Color color = {0xff, 0xff, 0xff, 0xff};
+	SDL_Surface *s = must(TTF_RenderText_Blended_Wrapped(
+		font, text, 0, color, 0
+	));
+	t->texture = must(SDL_CreateTextureFromSurface(t->renderer, s));
+	SDL_DestroySurface(s);
+	float tw, th;
+	SDL_GetTextureSize(t->texture, &tw, &th);
+	SDL_SetWindowSize(t->window, tw + PADDING*2, th + PADDING*2);
+	SDL_SyncWindow(t->window);
+}
+
+void show_tooltip(tooltip *t, int x, int y) {
+	if (!(SDL_GetWindowFlags(window) & SDL_WINDOW_MOUSE_FOCUS)) {
+		hide_tooltip(t);
+		return;
+	}
+	if (!t->texture) {
+		hide_tooltip(t);
+		return;
+	}
+	float tw, th;
+	SDL_GetTextureSize(t->texture, &tw, &th);
+	SDL_SetWindowPosition(t->window, x + PADDING, y - th - PADDING*3);
+	if (t->hidden) {
+		SDL_ShowWindow(t->window);
+		SDL_SyncWindow(t->window);
+		t->hidden = false;
+	}
+
+	SDL_SetRenderDrawColor(t->renderer, 0, 0, 0x20, 0xff);
+	SDL_RenderClear(t->renderer);
+	SDL_SetRenderDrawColor(t->renderer, 0, 0, 0, 0xff);
+	SDL_FRect dst = {PADDING, PADDING, tw, th};
+	SDL_RenderTexture(t->renderer, t->texture, NULL, &dst);
+	SDL_FRect border_rect = {0, 0, tw + PADDING*2, th + PADDING*2};
+	SDL_SetRenderDrawColor(t->renderer, 0x50, 0x50, 0x50, 0xff);
+	SDL_RenderRect(t->renderer, &border_rect);
+	must(SDL_RenderPresent(t->renderer));
+}
+
+void hide_tooltip(tooltip *t) {
+	if (t->window && !t->hidden) {
+		SDL_HideWindow(t->window);
+		t->hidden = true;
+	}
+}
diff --git a/src/tooltip.h b/src/tooltip.h
new file mode 100644
index 0000000..f9385fc
--- /dev/null
+++ b/src/tooltip.h
@@ -0,0 +1,19 @@
+#ifndef TOOLTIP_H
+#define TOOLTIP_H
+
+#include <SDL3/SDL.h>
+#include <stdbool.h>
+
+typedef struct tooltip {
+	SDL_Window *window;
+	SDL_Renderer *renderer;
+	SDL_Texture *texture;
+	uint64_t hash;
+	bool hidden;
+} tooltip;
+
+void set_tooltip_text(tooltip *t, const char *text);
+void show_tooltip(tooltip *t, int x, int y);
+void hide_tooltip(tooltip *t);
+
+#endif