replace non-standard qsort_r with qsort

I've tried to make as few changes, as possible.

Usually the reason for using qsort_r is, that you can pass an extra userdata pointer to the
compare function. However, in sway list_sort wrapped qsort_r and always called a wrapper
function for comparing, the wrapper function then had the real compare function as argument.
The only thing, that the wrapper function does, is dereferencing the 'left' and 'right' function
arguments before passing them to the real compare function.

I have renamed list_sort to list_qsort to avoid confusion (so nobody tries to use list_qsort like
list_sort) and removed the wrapper functionality. Now the dereferencing must be done in the
compare function, that gets passed.

Some compare functions were used in both list_sort and list_seq_find. To make the difference
clear, I've added a '_qsort' suffix to the compare functions, that are intended to be used with
the new list_qsort. (In other words: list_qsort is not compatible anymore with list_seq_find).

- Changed and renamed function (it isn't used anywhere but in commands.c, and only for sorting):
	compare_set -> compare_set_qsort
- New wrapper functions:
	sway_binding_cmp_qsort (for sway_binding_cmp)
	sway_mouse_binding_cmp_qsort (for sway_mouse_binding_cmp)

common/list.c

@@ -50,14 +50,8 @@ void list_cat(list_t *list, list_t *source) {
 	}
 }
 
-// pass the pointer of the object we care about to the comparison function
-static int list_cmp(const void *l, const void *r, void *_cmp) {
-	int (*cmp)(const void *, const void *) = _cmp;
-	return cmp(*(void**)l, *(void**)r);
-}
-
-void list_sort(list_t *list, int compare(const void *left, const void *right)) {
-	qsort_r(list->items, list->length, sizeof(void *), list_cmp, compare);
+void list_qsort(list_t* list, int compare(const void *left, const void *right)) {
+	qsort(list->items, list->length, sizeof(void *), compare);
 }
 
 int list_seq_find(list_t *list, int compare(const void *item, const void *data), const void *data) {

include/config.h

@@ -179,10 +179,12 @@ void free_output_config(struct output_config *oc);
 int workspace_output_cmp_workspace(const void *a, const void *b);
 
 int sway_binding_cmp(const void *a, const void *b);
+int sway_binding_cmp_qsort(const void *a, const void *b);
 int sway_binding_cmp_keys(const void *a, const void *b);
 void free_sway_binding(struct sway_binding *sb);
 
 int sway_mouse_binding_cmp(const void *a, const void *b);
+int sway_mouse_binding_cmp_qsort(const void *a, const void *b);
 int sway_mouse_binding_cmp_buttons(const void *a, const void *b);
 void free_sway_mouse_binding(struct sway_mouse_binding *smb);
 

include/list.h

@@ -13,8 +13,9 @@ void list_add(list_t *list, void *item);
 void list_insert(list_t *list, int index, void *item);
 void list_del(list_t *list, int index);
 void list_cat(list_t *list, list_t *source);
-// See qsort
-void list_sort(list_t *list, int compare(const void *left, const void *right));
+// See qsort. Remember to use *_qsort functions as compare functions,
+// because they dereference the left and right arguments first!
+void list_qsort(list_t *list, int compare(const void *left, const void *right));
 // Return index for first item in list that returns 0 for given compare
 // function or -1 if none matches.
 int list_seq_find(list_t *list, int compare(const void *item, const void *cmp_to), const void *cmp_to);

sway/commands.c

@@ -219,7 +219,7 @@ static struct cmd_results *cmd_bindsym(int argc, char **argv) {
 	}
 	binding->order = binding_order++;
 	list_add(mode->bindings, binding);
-	list_sort(mode->bindings, sway_binding_cmp);
+	list_qsort(mode->bindings, sway_binding_cmp_qsort);
 
 	sway_log(L_DEBUG, "bindsym - Bound %s to command %s", argv[0], binding->command);
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
@@ -1255,9 +1255,9 @@ static struct cmd_results *cmd_scratchpad(int argc, char **argv) {
 }
 
 // sort in order of longest->shortest
-static int compare_set(const void *_l, const void *_r) {
-	struct sway_variable const *l = _l;
-	struct sway_variable const *r = _r;
+static int compare_set_qsort(const void *_l, const void *_r) {
+	struct sway_variable const *l = *(void **)_l;
+	struct sway_variable const *r = *(void **)_r;
 	return strlen(r->name) - strlen(l->name);
 }
 
@@ -1284,7 +1284,7 @@ static struct cmd_results *cmd_set(int argc, char **argv) {
 		var = malloc(sizeof(struct sway_variable));
 		var->name = strdup(argv[0]);
 		list_add(config->symbols, var);
-		list_sort(config->symbols, compare_set);
+		list_qsort(config->symbols, compare_set_qsort);
 	}
 	var->value = join_args(argv + 1, argc - 1);
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
@@ -1620,7 +1620,7 @@ static struct cmd_results *bar_cmd_bindsym(int argc, char **argv) {
 		list_del(bar->bindings, i);
 	}
 	list_add(bar->bindings, binding);
-	list_sort(bar->bindings, sway_mouse_binding_cmp);
+	list_qsort(bar->bindings, sway_mouse_binding_cmp_qsort);
 
 	sway_log(L_DEBUG, "bindsym - Bound %s to command %s when clicking swaybar", argv[0], binding->command);
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);

sway/config.c

@@ -642,6 +642,10 @@ int sway_binding_cmp(const void *a, const void *b) {
 	return lenient_strcmp(binda->command, bindb->command);
 }
 
+int sway_binding_cmp_qsort(const void *a, const void *b) {
+	return sway_binding_cmp(*(void **)a, *(void **)b);
+}
+
 void free_sway_binding(struct sway_binding *binding) {
 	if (binding->keys) {
 		for (int i = 0; i < binding->keys->length; i++) {
@@ -675,6 +679,10 @@ int sway_mouse_binding_cmp(const void *a, const void *b) {
 	return lenient_strcmp(binda->command, bindb->command);
 }
 
+int sway_mouse_binding_cmp_qsort(const void *a, const void *b) {
+	return sway_mouse_binding_cmp(*(void **)a, *(void **)b);
+}
+
 void free_sway_mouse_binding(struct sway_mouse_binding *binding) {
 	if (binding->command) {
 		free(binding->command);