refactor: Eliminate Friends global variable (step 3).

Complete the transition to per-instance FriendsList by heap-allocating
it within the Toxic struct and removing the static instance in
friendlist.c.

Includes a new portable toxic_qsort_r wrapper to eliminate the need for
static state during friend list sorting.

Author: iphydf

src/friendlist.c

@@ -34,11 +34,13 @@
 
 static uint8_t blocklist_view = 0;   /* 0 if we're in friendlist view, 1 if we're in blocklist view */
 
-static FriendsList Friends;
-
 void init_friendlist(Toxic *toxic)
 {
-    toxic->friends = &Friends;
+    toxic->friends = calloc(1, sizeof(FriendsList));
+
+    if (toxic->friends == NULL) {
+        exit_toxic_err(FATALERR_MEMORY, "failed in init_friendlist");
+    }
 }
 
 static struct Blocked {
@@ -350,15 +352,15 @@ int load_blocklist(char *path)
 }
 
 #define S_WEIGHT 100000
-static FriendsList *sorting_friends;
-static int index_name_cmp(const void *n1, const void *n2)
+static int index_name_cmp(const void *n1, const void *n2, void *arg)
 {
-    int res = qsort_strcasecmp_hlpr(sorting_friends->list[*(const uint32_t *) n1].name,
-                                    sorting_friends->list[*(const uint32_t *) n2].name);
+    FriendsList *friends = arg;
+    int res = qsort_strcasecmp_hlpr(friends->list[*(const uint32_t *) n1].name,
+                                    friends->list[*(const uint32_t *) n2].name);
 
     /* Use weight to make qsort always put online friends before offline */
-    res = sorting_friends->list[*(const uint32_t *) n1].connection_status ? (res - S_WEIGHT) : (res + S_WEIGHT);
-    res = sorting_friends->list[*(const uint32_t *) n2].connection_status ? (res + S_WEIGHT) : (res - S_WEIGHT);
+    res = friends->list[*(const uint32_t *) n1].connection_status ? (res - S_WEIGHT) : (res + S_WEIGHT);
+    res = friends->list[*(const uint32_t *) n2].connection_status ? (res + S_WEIGHT) : (res - S_WEIGHT);
 
     return res;
 }
@@ -376,8 +378,7 @@ void sort_friendlist_index(FriendsList *friends)
     }
 
     if (friends->num_friends > 0) {
-        sorting_friends = friends;
-        qsort(friends->index, friends->num_friends, sizeof(uint32_t), index_name_cmp);
+        toxic_qsort_r(friends->index, friends->num_friends, sizeof(uint32_t), index_name_cmp, friends);
     }
 }
 

src/main.c

@@ -1214,6 +1214,7 @@ static Toxic *toxic_init(void)
         free(toxic->c_config);
         free(toxic->run_opts);
         free(toxic->windows);
+        free(toxic->friends);
         free(toxic);
         return NULL;
     }

src/misc_tools.c

@@ -295,6 +295,32 @@ int qsort_ptr_char_array_helper(const void *str1, const void *str2)
     return strcasecmp(*(const char *const *)str1, *(const char *const *)str2);
 }
 
+struct qsort_r_data {
+    void *arg;
+    int (*compar)(const void *, const void *, void *);
+};
+
+#ifdef __APPLE__
+static int qsort_r_compar_apple(void *thunk, const void *a, const void *b)
+{
+    struct qsort_r_data *data = thunk;
+    return data->compar(a, b, data->arg);
+}
+
+#endif
+
+void toxic_qsort_r(void *base, size_t nmemb, size_t size,
+                   int (*compar)(const void *, const void *, void *),
+                   void *arg)
+{
+#if defined(__APPLE__)
+    struct qsort_r_data data = { arg, compar };
+    qsort_r(base, nmemb, size, &data, qsort_r_compar_apple);
+#else
+    qsort_r(base, nmemb, size, compar, arg);
+#endif
+}
+
 /* List of characters we don't allow in nicks. */
 static const char invalid_nick_chars[] = {':', '/', '\0', '\a', '\b', '\f', '\n', '\r', '\t', '\v'};
 

src/misc_tools.h

@@ -151,6 +151,17 @@ int qsort_strcasecmp_hlpr(const void *str1, const void *str2);
 /* case-insensitive string compare function for use with qsort */
 int qsort_ptr_char_array_helper(const void *str1, const void *str2);
 
+/* Portable wrapper for qsort_r.
+ *
+ * Signature matches the GNU version:
+ * void qsort_r(void *base, size_t nmemb, size_t size,
+ *             int (*compar)(const void *, const void *, void *),
+ *             void *arg);
+ */
+void toxic_qsort_r(void *base, size_t nmemb, size_t size,
+                   int (*compar)(const void *, const void *, void *),
+                   void *arg);
+
 /* Returns true if nick is valid.
  *
  * A valid toxic nick:

src/toxic.c

@@ -88,6 +88,7 @@ static void kill_toxic(Toxic *toxic)
     free(toxic->c_config);
     free(toxic->run_opts);
     free(toxic->windows);
+    free(toxic->friends);
     paths_free(toxic->paths);
     free(toxic);
 }