cleanup: Reduce the amount of "extern" in .c files.

There is no check at all that the types of externs actually match the
type of the definition. This just accidentally was not a problem, but now
the compiler helps a bit in keeping it that way.

src/api.c

@@ -41,9 +41,6 @@ Tox              *user_tox;
 static WINDOW    *cur_window;
 static ToxWindow *self_window;
 
-extern FriendsList Friends;
-extern struct user_settings *user_settings;
-
 void api_display(const char *const msg)
 {
     if (msg == NULL) {

src/audio_call.c

@@ -60,14 +60,8 @@
 #endif /* ALC_ALL_DEVICES_SPECIFIER */
 #endif /* __APPLE__ */
 
-extern FriendsList Friends;
-extern ToxWindow *windows[MAX_WINDOWS_NUM];
-
 struct CallControl CallControl;
 
-extern struct user_settings *user_settings;
-extern struct Winthread Winthread;
-
 void on_call(ToxAV *av, uint32_t friend_number, bool audio_enabled, bool video_enabled,
              void *user_data);
 void on_call_state(ToxAV *av, uint32_t friend_number, uint32_t state, void *user_data);

src/bootstrap.c

@@ -39,9 +39,7 @@
 #include "settings.h"
 #include "windows.h"
 
-extern struct arg_opts arg_opts;
 extern struct user_settings *user_settings;
-extern struct Winthread Winthread;
 
 /* URL that we get the JSON encoded nodes list from. */
 #define NODES_LIST_URL "https://nodes.tox.chat/json"
@@ -59,7 +57,6 @@ extern struct Winthread Winthread;
 
 #define IP_MAX_SIZE 45
 #define IP_MIN_SIZE 7
-#define PORT_MAX_SIZE 5
 
 #define LAST_SCAN_JSON_KEY "\"last_scan\":"
 #define LAST_SCAN_JSON_KEY_LEN (sizeof(LAST_SCAN_JSON_KEY) - 1)

src/chat.c

@@ -58,12 +58,6 @@
 #endif /* VIDEO */
 #endif /* AUDIO */
 
-extern char *DATA_FILE;
-extern FriendsList Friends;
-
-extern struct Winthread Winthread;
-extern struct user_settings *user_settings;
-
 #ifdef AUDIO
 static void init_infobox(ToxWindow *self);
 static void kill_infobox(ToxWindow *self);

src/conference.c

@@ -63,8 +63,6 @@
 #include "toxic_strings.h"
 #include "windows.h"
 
-extern char *DATA_FILE;
-
 #define MAX_CONFERENCE_NUM (MAX_WINDOWS_NUM - 2)
 #define CONFERENCE_EVENT_WAIT 30
 

src/friendlist.c

@@ -37,6 +37,7 @@
 #include "log.h"
 #include "misc_tools.h"
 #include "notify.h"
+#include "prompt.h"
 #include "settings.h"
 #include "toxic.h"
 #include "windows.h"
@@ -46,13 +47,6 @@
 #endif
 
 
-extern char *DATA_FILE;
-extern char *BLOCK_FILE;
-extern ToxWindow *prompt;
-extern struct Winthread Winthread;
-extern struct user_settings *user_settings;
-extern struct arg_opts arg_opts;
-
 static uint8_t blocklist_view = 0;   /* 0 if we're in friendlist view, 1 if we're in blocklist view */
 
 FriendsList Friends;

src/friendlist.h

@@ -101,6 +101,8 @@ typedef struct {
     ToxicFriend *list;
 } FriendsList;
 
+extern FriendsList Friends;
+
 ToxWindow *new_friendlist(void);
 void friendlist_onInit(ToxWindow *self, Tox *m);
 void disable_chatwin(uint32_t f_num);

src/global_commands.c

@@ -42,11 +42,6 @@
 #include "game_base.h"
 #endif
 
-extern char *DATA_FILE;
-extern ToxWindow *prompt;
-extern FriendsList Friends;
-extern FriendRequests FrndRequests;
-
 /* command functions */
 void cmd_accept(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
 {

src/name_lookup.c

@@ -33,9 +33,6 @@
 #include "toxic.h"
 #include "windows.h"
 
-extern struct arg_opts arg_opts;
-extern struct Winthread Winthread;
-
 #define NAMESERVER_API_PATH "api"
 #define SERVER_KEY_SIZE 32
 #define MAX_SERVERS 50

src/prompt.h

@@ -40,6 +40,9 @@ typedef struct FriendRequests {
     struct friend_request request[MAX_FRIEND_REQUESTS];
 } FriendRequests;
 
+extern ToxWindow *prompt;
+extern FriendRequests FrndRequests;
+
 ToxWindow *new_prompt(void);
 
 void prep_prompt_win(void);

src/settings.h

@@ -96,6 +96,8 @@ struct user_settings {
 #endif
 };
 
+extern struct user_settings *user_settings;
+
 enum settings_values {
     AUTOLOG_OFF = 0,
     AUTOLOG_ON = 1,

src/toxic.c

@@ -74,7 +74,7 @@
 #ifdef VIDEO
 #include "video_call.h"
 #endif /* VIDEO */
-ToxAV *av;
+static ToxAV *av;
 #endif /* AUDIO */
 
 #ifdef PYTHON
@@ -98,8 +98,8 @@ ToxWindow *prompt = NULL;
 #define MAX_PASSWORD_LEN 64
 
 struct Winthread Winthread;
-struct cqueue_thread cqueue_thread;
-struct av_thread av_thread;
+static struct cqueue_thread cqueue_thread;
+static struct av_thread av_thread;
 struct arg_opts arg_opts;
 
 // This struct is not thread safe. It should only ever be written to from the main thread

src/toxic.h

@@ -145,5 +145,7 @@ void on_friend_typing(Tox *m, uint32_t friendnumber, bool is_typing, void *userd
 void on_friend_read_receipt(Tox *m, uint32_t friendnumber, uint32_t receipt, void *userdata);
 void on_lossless_custom_packet(Tox *m, uint32_t friendnumber, const uint8_t *data, size_t length, void *userdata);
 
+extern char *DATA_FILE;
+extern char *BLOCK_FILE;
 
 #endif /* TOXIC_H */

src/video_device.c

@@ -92,21 +92,21 @@ typedef struct VideoDevice {
 
 } VideoDevice;
 
-const char *dvideo_device_names[2];              /* Default device */
-char *video_devices_names[2][MAX_DEVICES]; /* Container of available devices */
+static const char *dvideo_device_names[2];        /* Default device */
+static char *video_devices_names[2][MAX_DEVICES]; /* Container of available devices */
 static int size[2];                               /* Size of above containers */
-VideoDevice *video_devices_running[2][MAX_DEVICES] = {{NULL}};     /* Running devices */
-uint32_t primary_video_device[2];          /* Primary device */
+static VideoDevice *video_devices_running[2][MAX_DEVICES] = {{NULL}}; /* Running devices */
+static uint32_t primary_video_device[2];                              /* Primary device */
 
 static ToxAV *av = NULL;
 
 /* q_mutex */
 #define lock pthread_mutex_lock(&video_mutex)
 #define unlock pthread_mutex_unlock(&video_mutex)
-pthread_mutex_t video_mutex;
+static pthread_mutex_t video_mutex;
 
-bool video_thread_running = true,
-     video_thread_paused = true;                /* Thread control */
+static bool video_thread_running = true;
+static bool video_thread_paused = true;                /* Thread control */
 
 void *video_thread_poll(void *);
 

src/windows.c

@@ -41,16 +41,10 @@
 #include "game_base.h"
 #endif
 
-extern char *DATA_FILE;
-extern struct Winthread Winthread;
-
 ToxWindow *windows[MAX_WINDOWS_NUM];
 static uint8_t active_window_index;
 static int num_active_windows;
 
-extern ToxWindow *prompt;
-extern struct user_settings *user_settings;
-
 /* CALLBACKS START */
 void on_friend_request(Tox *m, const uint8_t *public_key, const uint8_t *data, size_t length, void *userdata)
 {

src/windows.h

@@ -114,6 +114,8 @@ struct Winthread {
     volatile sig_atomic_t last_refresh_flag;
 };
 
+extern struct Winthread Winthread;
+
 struct cqueue_thread {
     pthread_t tid;
 };
@@ -147,6 +149,8 @@ struct arg_opts {
     uint16_t tcp_port;
 };
 
+extern struct arg_opts arg_opts;
+
 typedef struct ToxWindow ToxWindow;
 typedef struct StatusBar StatusBar;
 typedef struct PromptBuf PromptBuf;
@@ -233,6 +237,8 @@ struct ToxWindow {
     WINDOW *window_bar;
 };
 
+extern ToxWindow *windows[MAX_WINDOWS_NUM];
+
 /* statusbar info holder */
 struct StatusBar {
     WINDOW *topline;