config: introduce quick-select-allow-editing

If false while quick-select is true, the left mouse button acts in the same
way as the right mouse button.

README.md

@@ -30,4 +30,4 @@ GPL-3.0-only
 
 See `LICENSE` for more information.
 
-Copyright © 2024 Kirill Primak
+Copyright © 2025 Kirill Primak

dulcepan.cfg

@@ -33,6 +33,10 @@ animation-duration = 0
 # or when a whole output is selected with a mouse button.
 quick-select = false
 
+# If true, dulcepan will allow editing the current selection if quick-select is
+# true. Has no effect if quick-select is false.
+quick-select-allow-editing = true
+
 # If true, dulcepan will remember selection between runs.
 # The state is stored at $XDG_CACHE_HOME/dulcepan.
 persistence = true
@@ -40,6 +44,7 @@ persistence = true
 # PNG (zlib) compression level, 0-9
 png-compression = 6
 
-# Key bindings
+# Key bindings. Each binding is a comma-separated list of key names; empty names
+# are ignored. A binding may be empty.
 quit-key = Escape
-save-key = Space
+save-key = Space,Enter

meson.build

@@ -1,7 +1,7 @@
 project(
   'dulcepan',
   'c',
-  version: '1.0.1',
+  version: '1.0.3',
   license: 'GPL-3.0-only',
   default_options: [
     'c_std=c11',

src/config.c

@@ -15,7 +15,22 @@ static inline void bytes_to_color(uint8_t bytes[static 4], float out[static 4])
 	}
 }
 
-static void load_color(const char *value, int line_idx, float out[static 4]) {
+static void keybinding_init(struct dp_keybinding *kb, xkb_keysym_t *syms, size_t n_syms) {
+	*kb = (struct dp_keybinding){
+		.syms = dp_zalloc(sizeof(*kb->syms) * n_syms),
+		.n_syms = n_syms,
+	};
+	for (size_t i = 0; i < n_syms; i++) {
+		xkb_keysym_t sym = syms[i];
+		kb->syms[i] = sym;
+	}
+}
+
+static void keybinding_finish(struct dp_keybinding *kb) {
+	free(kb->syms);
+}
+
+static void load_color(char *value, int line_idx, float out[static 4]) {
 	size_t len = strlen(value);
 
 	uint8_t bytes[4] = {0, 0, 0, 0};
@@ -46,7 +61,7 @@ bad:
 	dp_log_fatal("Config: invalid color %s on line %d", value, line_idx);
 }
 
-static void load_int(const char *value, int line_idx, int min, int max, int *out) {
+static void load_int(char *value, int line_idx, int min, int max, int *out) {
 	const char *p = value;
 	int mul = 1;
 	if (*p == '-') {
@@ -68,7 +83,7 @@ static void load_int(const char *value, int line_idx, int min, int max, int *out
 	}
 }
 
-static void load_bool(const char *value, int line_idx, bool *out) {
+static void load_bool(char *value, int line_idx, bool *out) {
 	if (strcmp(value, "true") == 0) {
 		*out = true;
 	} else if (strcmp(value, "false") == 0) {
@@ -78,19 +93,31 @@ static void load_bool(const char *value, int line_idx, bool *out) {
 	}
 }
 
-static void load_key(const char *value, int line_idx, xkb_keysym_t *out) {
-	*out = xkb_keysym_from_name(value, XKB_KEYSYM_CASE_INSENSITIVE);
-	if (*out == XKB_KEY_NoSymbol) {
-		dp_log_fatal("Config: unknown key %s on line %d", value, line_idx);
+static void load_key(char *value, int line_idx, struct dp_keybinding *out) {
+	size_t n_syms = 0;
+	xkb_keysym_t syms[32];
+
+	char *save_ptr = NULL;
+	for (char *name; (name = strtok_r(value, ",", &save_ptr)) != NULL; value = NULL) {
+		if (n_syms == sizeof(syms) / sizeof(*syms)) {
+			// chill out
+			dp_log_fatal("Config: too many keys on line %d", line_idx);
 		}
+		xkb_keysym_t sym = xkb_keysym_from_name(name, XKB_KEYSYM_CASE_INSENSITIVE);
+		if (sym == XKB_KEY_NoSymbol) {
+			dp_log_fatal("Config: unknown key \"%s\" on line %d", name, line_idx);
+		}
+		syms[n_syms++] = sym;
+	}
+
+	keybinding_finish(out);
+	keybinding_init(out, syms, n_syms);
 }
 
 void dp_config_load(struct dp_state *state, const char *user_path) {
 	struct dp_config *config = &state->config;
 
 	*config = (struct dp_config){
-		.quit_key = XKB_KEY_Escape,
-		.save_key = XKB_KEY_space,
 		.border_size = 2,
 		.border_gradient = DP_BORDER_GRADIENT_NONE,
 		.gradient_angle = 45,
@@ -98,13 +125,18 @@ void dp_config_load(struct dp_state *state, const char *user_path) {
 		.animation_duration = 0,
 		.png_compression = 6,
 		.quick_select = false,
+		.quick_select_allow_editing = true,
 		.persistence = true,
 	};
+
 	bytes_to_color((uint8_t[]){0xff, 0xff, 0xff, 0x40}, config->unselected_color);
 	bytes_to_color((uint8_t[]){0x00, 0x00, 0x00, 0x00}, config->selected_color);
 	bytes_to_color((uint8_t[]){0xff, 0xff, 0xff, 0xff}, config->border_color);
 	bytes_to_color((uint8_t[]){0x00, 0x00, 0x00, 0xff}, config->border_secondary_color);
 
+	keybinding_init(&config->quit_kb, (xkb_keysym_t[]){XKB_KEY_Escape}, 1);
+	keybinding_init(&config->save_kb, (xkb_keysym_t[]){XKB_KEY_space, XKB_KEY_Return}, 2);
+
 	FILE *fp = NULL;
 	if (user_path != NULL) {
 		fp = fopen(user_path, "r");
@@ -212,12 +244,14 @@ void dp_config_load(struct dp_state *state, const char *user_path) {
 			load_int(value, line_idx, 0, 9, &config->png_compression);
 		} else if (strcmp(key, "quick-select") == 0) {
 			load_bool(value, line_idx, &config->quick_select);
+		} else if (strcmp(key, "quick-select-allow-editing") == 0) {
+			load_bool(value, line_idx, &config->quick_select_allow_editing);
 		} else if (strcmp(key, "persistence") == 0) {
 			load_bool(value, line_idx, &config->persistence);
 		} else if (strcmp(key, "quit-key") == 0) {
-			load_key(value, line_idx, &config->quit_key);
+			load_key(value, line_idx, &config->quit_kb);
 		} else if (strcmp(key, "save-key") == 0) {
-			load_key(value, line_idx, &config->save_key);
+			load_key(value, line_idx, &config->save_kb);
 		} else {
 			dp_log_error("Config: unknown key %s on line %d", key, line_idx);
 		}
@@ -226,3 +260,10 @@ void dp_config_load(struct dp_state *state, const char *user_path) {
 
 	fclose(fp);
 }
+
+void dp_config_finish(struct dp_state *state) {
+	struct dp_config *config = &state->config;
+
+	keybinding_finish(&config->quit_kb);
+	keybinding_finish(&config->save_kb);
+}

src/dulcepan.h

@@ -126,6 +126,14 @@ struct dp_selection {
 	int resize_edges;
 	// Resize anchor
 	double resize_x, resize_y;
+
+	// Used for toggling
+	struct {
+		// If not NULL, the current output has been selected via the dedicated
+		// action rather than by persistent state loading or manual resizing
+		struct dp_output *output;
+		double x, y, width, height;
+	} last_partial;
 };
 
 enum dp_file_format {
@@ -141,6 +149,11 @@ enum dp_border_gradient {
 	DP_BORDER_GRADIENT_LOOP,
 };
 
+struct dp_keybinding {
+	xkb_keysym_t *syms;
+	size_t n_syms;
+};
+
 struct dp_config {
 	// RGBA, not premultiplied
 	float unselected_color[4];
@@ -148,8 +161,8 @@ struct dp_config {
 	float border_color[4];
 	float border_secondary_color[4];
 
-	xkb_keysym_t quit_key;
-	xkb_keysym_t save_key;
+	struct dp_keybinding quit_kb;
+	struct dp_keybinding save_kb;
 
 	int border_size; // 0 if disabled
 	enum dp_border_gradient border_gradient;
@@ -158,7 +171,10 @@ struct dp_config {
 	int animation_duration; // In milliseconds
 
 	int png_compression;
+
 	bool quick_select;
+	bool quick_select_allow_editing;
+
 	bool persistence;
 };
 
@@ -195,6 +211,8 @@ struct dp_state {
 	const char *output_path; // May be NULL
 	enum dp_file_format output_format;
 
+	bool allow_selection_editing;
+
 	bool show_cursors;
 
 	cairo_pattern_t *border_pattern;
@@ -204,6 +222,7 @@ struct dp_state {
 };
 
 void dp_config_load(struct dp_state *state, const char *user_path);
+void dp_config_finish(struct dp_state *state);
 
 // When done, data must be unmapped
 struct wl_buffer *dp_buffer_create(struct dp_state *state, int32_t width, int32_t height,
@@ -226,7 +245,7 @@ void dp_select_stop_interactive(struct dp_selection *selection);
 void dp_select_notify_pointer_position(
 		struct dp_selection *selection, struct dp_output *output, double x, double y);
 
-void dp_select_whole(struct dp_selection *selection, struct dp_output *output);
+void dp_select_toggle_whole(struct dp_selection *selection, struct dp_output *output);
 
 void dp_save(struct dp_state *state);
 

src/main.c

@@ -1,6 +1,7 @@
 #include <getopt.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <wayland-client-core.h>
 #include <wayland-client-protocol.h>
 #include <xkbcommon/xkbcommon.h>
@@ -167,14 +168,15 @@ static void help(const char *prog) {
 			"  -o <path>    Specify the output file path.\n"
 			"\n"
 			"If the output file path is not specified, the resuling image will be printed to\n"
-			"the standard output. If the output file format is not specified, it is guessed\n"
-			"from the output file path if it's specified, and assumed to be PNG otherwise.\n"
+			"the standard output, which is expected to not be a terminal. If the output file\n"
+			"format is not specified, it is guessed from the output file path if it's\n"
+			"specified, and assumed to be PNG otherwise.\n"
 			"\n"
 			"Supported formats: png, ppm.\n"
 			"\n"
 			"Use the left or right mouse button to select a part of the output. A selection\n"
 			"can also be moved and resized with the left mouse button. Clicking the middle\n"
-			"mouse button selects the entire output.\n",
+			"mouse button toggles the selection of the entire output.\n",
 			prog);
 }
 
@@ -210,9 +212,13 @@ int main(int argc, char **argv) {
 		}
 	}
 
-	state.basedir_ctx = sfdo_basedir_ctx_create();
-
-	dp_config_load(&state, config_path);
+	if (state.output_path == NULL && isatty(STDOUT_FILENO)) {
+		fprintf(stderr,
+				"Refusing to run as the standard output is a terminal and there's no output file\n"
+				"path specified.\n\n");
+		help(argv[0]);
+		exit(1);
+	}
 
 	if (state.output_format == DP_FILE_UNKNOWN) {
 		if (state.output_path != NULL) {
@@ -227,6 +233,10 @@ int main(int argc, char **argv) {
 		}
 	}
 
+	state.basedir_ctx = sfdo_basedir_ctx_create();
+
+	dp_config_load(&state, config_path);
+
 	wl_list_init(&state.outputs);
 	wl_list_init(&state.seats);
 
@@ -238,6 +248,9 @@ int main(int argc, char **argv) {
 	state.xkb_context = xkb_context_new(XKB_CONTEXT_NO_FLAGS);
 
 	struct dp_config *config = &state.config;
+
+	state.allow_selection_editing = !config->quick_select || config->quick_select_allow_editing;
+
 	if (config->border_gradient != DP_BORDER_GRADIENT_NONE) {
 		state.border_pattern = cairo_pattern_create_linear(0, 0, 1, 0);
 		cairo_pattern_add_color_stop_rgba(state.border_pattern, 0, config->border_color[0],
@@ -268,6 +281,8 @@ int main(int argc, char **argv) {
 
 	run(&state);
 
+	dp_config_finish(&state);
+
 	cairo_pattern_destroy(state.border_pattern);
 
 	xkb_context_unref(state.xkb_context);

src/output.c

@@ -79,6 +79,12 @@ static void frame_handle_buffer(void *data, struct zwlr_screencopy_frame_v1 *fra
 		wl_buffer_destroy(output->frame_buffer);
 	}
 
+	if ((int32_t)width != output->width || (int32_t)height != output->height) {
+		dp_log_fatal("Output/buffer size mismatch: mode=%" PRIi32 "x%" PRIi32 ", buffer=%" PRIu32
+					 "x%" PRIu32,
+				output->width, output->height, width, height);
+	}
+
 	output->frame_format = format;
 	output->frame_stride = (int)stride;
 	output->frame_buffer = dp_buffer_create(output->state, output->width, output->height,
@@ -156,6 +162,10 @@ static void output_handle_geometry(void *data, struct wl_output *wl_output, int3
 
 static void output_handle_mode(void *data, struct wl_output *wl_output, uint32_t flags,
 		int32_t width, int32_t height, int32_t refresh) {
+	if ((flags & WL_OUTPUT_MODE_CURRENT) == 0) {
+		return;
+	}
+
 	struct dp_output *output = data;
 
 	if (output->has_geom) {
@@ -178,6 +188,7 @@ static void output_handle_done(void *data, struct wl_output *wl_output) {
 
 	assert(output->name != NULL);
 
+	assert(output->width > 0 && output->height > 0);
 	if ((output->transform & WL_OUTPUT_TRANSFORM_90) != 0) {
 		output->transformed_width = output->height;
 		output->transformed_height = output->width;

src/seat.c

@@ -50,6 +50,15 @@ static void keyboard_handle_leave(
 	// Ignored
 }
 
+static bool match_keybinding(struct dp_keybinding *kb, uint32_t sym) {
+	for (size_t i = 0; i < kb->n_syms; i++) {
+		if (sym == kb->syms[i]) {
+			return true;
+		}
+	}
+	return false;
+}
+
 static void keyboard_handle_key(void *data, struct wl_keyboard *wl_keyboard, uint32_t serial,
 		uint32_t time_msec, uint32_t keycode, enum wl_keyboard_key_state key_state) {
 	struct dp_seat *seat = data;
@@ -62,9 +71,9 @@ static void keyboard_handle_key(void *data, struct wl_keyboard *wl_keyboard, uin
 	struct dp_state *state = seat->state;
 	struct dp_config *config = &state->config;
 
-	if (keysym == config->quit_key) {
+	if (match_keybinding(&config->quit_kb, keysym)) {
 		state->status = DP_STATUS_QUIT;
-	} else if (keysym == config->save_key) {
+	} else if (match_keybinding(&config->save_kb, keysym)) {
 		state->status = DP_STATUS_SAVED;
 	}
 }
@@ -83,13 +92,15 @@ static const struct wl_keyboard_listener keyboard_listener = {
 	.modifiers = keyboard_handle_modifiers,
 };
 
-static enum wp_cursor_shape_device_v1_shape get_cursor_shape(struct dp_selection *selection) {
+static enum wp_cursor_shape_device_v1_shape get_cursor_shape(struct dp_state *state) {
+	if (state->allow_selection_editing) {
+		struct dp_selection *selection = &state->selection;
 		switch (selection->action) {
 		case DP_SELECTION_ACTION_NONE:
-		return WP_CURSOR_SHAPE_DEVICE_V1_SHAPE_CROSSHAIR;
+			break;
 		case DP_SELECTION_ACTION_RESIZING:
 			if (selection->width == 0 || selection->height == 0) {
-			return WP_CURSOR_SHAPE_DEVICE_V1_SHAPE_CROSSHAIR;
+				break;
 			}
 			switch (selection->resize_edges) {
 			case DP_EDGE_TOP:
@@ -116,17 +127,20 @@ static enum wp_cursor_shape_device_v1_shape get_cursor_shape(struct dp_selection
 					selection->width == selection->output->effective_width &&
 					selection->height == selection->output->effective_height) {
 				// Moving is impossible
-			return WP_CURSOR_SHAPE_DEVICE_V1_SHAPE_DEFAULT;
+				break;
 			}
 			return WP_CURSOR_SHAPE_DEVICE_V1_SHAPE_MOVE;
 		}
-	abort(); // Unreachable
+	}
+
+	// The default cursor
+	return WP_CURSOR_SHAPE_DEVICE_V1_SHAPE_CROSSHAIR;
 }
 
 static void update_cursor(struct dp_seat *seat) {
 	if (seat->cursor_shape_device != NULL) {
-		wp_cursor_shape_device_v1_set_shape(seat->cursor_shape_device, seat->pointer_serial,
-				get_cursor_shape(&seat->state->selection));
+		wp_cursor_shape_device_v1_set_shape(
+				seat->cursor_shape_device, seat->pointer_serial, get_cursor_shape(seat->state));
 	}
 }
 
@@ -172,7 +186,8 @@ static void pointer_handle_button(void *data, struct wl_pointer *wl_pointer, uin
 
 	struct dp_selection *selection = &state->selection;
 	if (button_state != WL_POINTER_BUTTON_STATE_PRESSED) {
-		if (selection->width > 0 && selection->height > 0 && state->config.quick_select) {
+		if (selection->action == DP_SELECTION_ACTION_RESIZING && selection->width > 0 &&
+				selection->height > 0 && state->config.quick_select) {
 			state->status = DP_STATUS_SAVED;
 		}
 		dp_select_stop_interactive(selection);
@@ -186,14 +201,14 @@ static void pointer_handle_button(void *data, struct wl_pointer *wl_pointer, uin
 	switch (button) {
 	case BTN_LEFT:
 	case BTN_RIGHT:
-		dp_select_start_interactive(
-				selection, seat->ptr_output, seat->ptr_x, seat->ptr_y, button == BTN_LEFT);
+		dp_select_start_interactive(selection, seat->ptr_output, seat->ptr_x, seat->ptr_y,
+				state->allow_selection_editing && button == BTN_LEFT);
 		update_cursor(seat);
 		break;
 	case BTN_MIDDLE:
-		dp_select_whole(selection, seat->ptr_output);
+		dp_select_toggle_whole(selection, seat->ptr_output);
 
-		// dp_select_whole() doesn't invalidate the interactive state, so do it manually
+		// Update the interaction state manually
 		dp_select_notify_pointer_position(selection, seat->ptr_output, seat->ptr_x, seat->ptr_y);
 		update_cursor(seat);
 

src/select.c

@@ -20,6 +20,24 @@ static void set_selected_output(struct dp_selection *selection, struct dp_output
 	}
 }
 
+static inline bool has_last_partial(struct dp_selection *selection) {
+	return selection->last_partial.output != NULL;
+}
+
+static inline void reset_last_partial(struct dp_selection *selection) {
+	selection->last_partial.output = NULL;
+}
+
+static bool has_partial(struct dp_selection *selection) {
+	struct dp_output *output = selection->output;
+	if (output == NULL) {
+		return false;
+	}
+
+	return selection->x != 0 || selection->y != 0 || selection->width != output->effective_width ||
+			selection->height != output->effective_height;
+}
+
 static void update_action(
 		struct dp_selection *selection, struct dp_output *output, double x, double y) {
 	if (output == selection->output) {
@@ -161,6 +179,8 @@ void dp_select_start_interactive(struct dp_selection *selection, struct dp_outpu
 	update_action(selection, output, x, y);
 	selection->action_active = true;
 
+	reset_last_partial(selection);
+
 	if (modify_existing) {
 		switch (selection->action) {
 		case DP_SELECTION_ACTION_NONE:
@@ -187,6 +207,8 @@ void dp_select_start_interactive(struct dp_selection *selection, struct dp_outpu
 	selection->resize_edges = DP_EDGE_BOTTOM | DP_EDGE_RIGHT;
 
 	init_resize(selection, x, y);
+
+	dp_output_redraw(output);
 }
 
 void dp_select_stop_interactive(struct dp_selection *selection) {
@@ -211,13 +233,35 @@ void dp_select_notify_pointer_position(
 	}
 }
 
-void dp_select_whole(struct dp_selection *selection, struct dp_output *output) {
+void dp_select_toggle_whole(struct dp_selection *selection, struct dp_output *output) {
+	if (selection->output == output && has_last_partial(selection)) {
+		// Toggle the selection back to the last partial one
+		set_selected_output(selection, selection->last_partial.output);
+
+		selection->x = selection->last_partial.x;
+		selection->y = selection->last_partial.y;
+		selection->width = selection->last_partial.width;
+		selection->height = selection->last_partial.height;
+
+		reset_last_partial(selection);
+	} else {
+		// Don't save another whole output selection as partial
+		if (has_partial(selection) && !has_last_partial(selection)) {
+			selection->last_partial.output = selection->output;
+
+			selection->last_partial.x = selection->x;
+			selection->last_partial.y = selection->y;
+			selection->last_partial.width = selection->width;
+			selection->last_partial.height = selection->height;
+		}
+
 		set_selected_output(selection, output);
 
 		selection->x = 0;
 		selection->y = 0;
 		selection->width = output->effective_width;
 		selection->height = output->effective_height;
-
-	dp_output_redraw(output);
+	}
+
+	dp_output_redraw(selection->output);
 }

src/util.c

@@ -28,6 +28,10 @@ void dp_log_fatal(const char *fmt, ...) {
 }
 
 void *dp_zalloc(size_t size) {
+	if (size == 0) {
+		return NULL;
+	}
+
 	void *ptr = calloc(1, size);
 	if (ptr == NULL) {
 		dp_log_fatal("Failed to allocate %zu bytes", size);