Remove a load of obsolete printf string limits.

In the previous commit I happened to notice a %.150s in a ppl_logevent
call, which was probably an important safety precaution a couple of
decades ago when that format string was being used for an sprintf into
a fixed-size buffer, but now it's just pointless cruft.

This commit removes all printf string formatting directives with a
compile-time fixed size, with the one exception of a %.3s used to cut
out a 3-letter month name in scpserver.c. In cases where the format
string in question was already going to an arbitrary-length function
like dupprintf or ppl_logevent, that's all I've done; in cases where
there was still a fixed-size buffer, I've replaced it with a dynamic
buffer and dupprintf.

ssh1login.c

@@ -448,8 +448,7 @@ static void ssh1_login_process_queue(PacketProtocolLayer *ppl)
     s->keyfile = conf_get_filename(s->conf, CONF_keyfile);
     if (!filename_is_null(s->keyfile)) {
         int keytype;
-        ppl_logevent("Reading key file \"%.150s\"",
+        ppl_logevent("Reading key file \"%s\"", filename_to_str(s->keyfile));
-                     filename_to_str(s->keyfile));
         keytype = key_type(s->keyfile);
         if (keytype == SSH_KEYTYPE_SSH1 ||
             keytype == SSH_KEYTYPE_SSH1_PUBLIC) {
@@ -655,7 +654,7 @@ static void ssh1_login_process_queue(PacketProtocolLayer *ppl)
                     s->cur_prompt->to_server = false;
                     s->cur_prompt->name = dupstr("SSH key passphrase");
                     add_prompt(s->cur_prompt,
-                               dupprintf("Passphrase for key \"%.100s\": ",
+                               dupprintf("Passphrase for key \"%s\": ",
                                          s->publickey_comment), false);
                     s->userpass_ret = seat_get_userpass_input(
                         s->ppl.seat, s->cur_prompt, NULL);

ssh2bpp.c

@@ -113,7 +113,7 @@ void ssh2_bpp_new_outgoing_crypto(
             (ssh2_cipher_alg(s->out.cipher)->flags & SSH_CIPHER_IS_CBC) &&
             !(s->bpp.remote_bugs & BUG_CHOKES_ON_SSH2_IGNORE));
 
-        bpp_logevent("Initialised %.200s outbound encryption",
+        bpp_logevent("Initialised %s outbound encryption",
                      ssh2_cipher_alg(s->out.cipher)->text_name);
     } else {
         s->out.cipher = NULL;
@@ -124,7 +124,7 @@ void ssh2_bpp_new_outgoing_crypto(
         s->out.mac = ssh2_mac_new(mac, s->out.cipher);
         mac->setkey(s->out.mac, mac_key);
 
-        bpp_logevent("Initialised %.200s outbound MAC algorithm%s%s",
+        bpp_logevent("Initialised %s outbound MAC algorithm%s%s",
                      ssh2_mac_alg(s->out.mac)->text_name,
                      etm_mode ? " (in ETM mode)" : "",
                      (s->out.cipher &&
@@ -176,7 +176,7 @@ void ssh2_bpp_new_incoming_crypto(
         ssh2_cipher_setkey(s->in.cipher, ckey);
         ssh2_cipher_setiv(s->in.cipher, iv);
 
-        bpp_logevent("Initialised %.200s inbound encryption",
+        bpp_logevent("Initialised %s inbound encryption",
                      ssh2_cipher_alg(s->in.cipher)->text_name);
     } else {
         s->in.cipher = NULL;
@@ -186,7 +186,7 @@ void ssh2_bpp_new_incoming_crypto(
         s->in.mac = ssh2_mac_new(mac, s->in.cipher);
         mac->setkey(s->in.mac, mac_key);
 
-        bpp_logevent("Initialised %.200s inbound MAC algorithm%s%s",
+        bpp_logevent("Initialised %s inbound MAC algorithm%s%s",
                      ssh2_mac_alg(s->in.mac)->text_name,
                      etm_mode ? " (in ETM mode)" : "",
                      (s->in.cipher &&

ssh2userauth.c

@@ -225,7 +225,7 @@ static void ssh2_userauth_process_queue(PacketProtocolLayer *ppl)
      */
     if (!filename_is_null(s->keyfile)) {
         int keytype;
-        ppl_logevent("Reading key file \"%.150s\"",
+        ppl_logevent("Reading key file \"%s\"",
                      filename_to_str(s->keyfile));
         keytype = key_type(s->keyfile);
         if (keytype == SSH_KEYTYPE_SSH2 ||
@@ -798,7 +798,7 @@ static void ssh2_userauth_process_queue(PacketProtocolLayer *ppl)
                         s->cur_prompt->to_server = false;
                         s->cur_prompt->name = dupstr("SSH key passphrase");
                         add_prompt(s->cur_prompt,
-                                   dupprintf("Passphrase for key \"%.100s\": ",
+                                   dupprintf("Passphrase for key \"%s\": ",
                                              s->publickey_comment),
                                    false);
                         s->userpass_ret = seat_get_userpass_input(

unix/uxpty.c

@@ -707,21 +707,29 @@ static void pty_real_select_result(Pty *pty, int fd, int event, int status)
 	close_on_exit = conf_get_int(pty->conf, CONF_close_on_exit);
 	if (close_on_exit == FORCE_OFF ||
 	    (close_on_exit == AUTO && pty->exit_code != 0)) {
-	    char message[512];
+	    char *message;
-            message[0] = '\0';
+            if (WIFEXITED(pty->exit_code)) {
-	    if (WIFEXITED(pty->exit_code))
+		message = dupprintf(
-		sprintf(message, "\r\n[pterm: process terminated with exit"
+                    "\r\n[pterm: process terminated with exit code %d]\r\n",
-			" code %d]\r\n", WEXITSTATUS(pty->exit_code));
+                    WEXITSTATUS(pty->exit_code));
-	    else if (WIFSIGNALED(pty->exit_code))
+            } else if (WIFSIGNALED(pty->exit_code)) {
 #ifdef HAVE_NO_STRSIGNAL
-		sprintf(message, "\r\n[pterm: process terminated on signal"
+		message = dupprintf(
-			" %d]\r\n", WTERMSIG(pty->exit_code));
+                    "\r\n[pterm: process terminated on signal %d]\r\n",
+                    WTERMSIG(pty->exit_code));
 #else
-		sprintf(message, "\r\n[pterm: process terminated on signal"
+		message = dupprintf(
-			" %d (%.400s)]\r\n", WTERMSIG(pty->exit_code),
+                    "\r\n[pterm: process terminated on signal %d (%s)]\r\n",
+                    WTERMSIG(pty->exit_code),
                     strsignal(WTERMSIG(pty->exit_code)));
 #endif
+            } else {
+                /* _Shouldn't_ happen, but if it does, a vague message
+                 * is better than no message at all */
+                message = dupprintf("\r\n[pterm: process terminated]\r\n");
+            }
 	    seat_stdout(pty->seat, message, strlen(message));
+            sfree(message);
 	}
 
         seat_eof(pty->seat);

windows/windlg.c

@@ -910,7 +910,7 @@ int win_seat_confirm_weak_crypto_primitive(
     static const char mbtitle[] = "%s Security Alert";
     static const char msg[] =
 	"The first %s supported by the server\n"
-	"is %.64s, which is below the configured\n"
+	"is %s, which is below the configured\n"
 	"warning threshold.\n"
 	"Do you want to continue with this connection?\n";
     char *message, *title;

windows/window.c

@@ -354,7 +354,7 @@ static void start_backend(void)
 {
     const struct BackendVtable *vt;
     const char *error;
-    char msg[1024], *title;
+    const char *title;
     char *realhost;
     int i;
 
@@ -379,17 +379,19 @@ static void start_backend(void)
                          conf_get_bool(conf, CONF_tcp_keepalives));
     if (error) {
 	char *str = dupprintf("%s Error", appname);
-	sprintf(msg, "Unable to open connection to\n"
+        char *msg = dupprintf("Unable to open connection to\n%s\n%s",
-		"%.800s\n" "%s", conf_dest(conf), error);
+                              conf_dest(conf), error);
 	MessageBox(NULL, msg, str, MB_ICONERROR | MB_OK);
 	sfree(str);
+	sfree(msg);
 	exit(0);
     }
     window_name = icon_name = NULL;
+    char *title_to_free = NULL;
     title = conf_get_str(conf, CONF_wintitle);
     if (!*title) {
-	sprintf(msg, "%s - %s", realhost, appname);
+	title_to_free = dupprintf("%s - %s", realhost, appname);
-	title = msg;
+	title = title_to_free;
     }
     sfree(realhost);
     win_set_title(wintw, title);
@@ -417,17 +419,20 @@ static void start_backend(void)
     }
 
     session_closed = false;
+
+    sfree(title_to_free);
 }
 
 static void close_session(void *ignored_context)
 {
-    char morestuff[100];
+    char *newtitle;
     int i;
 
     session_closed = true;
-    sprintf(morestuff, "%.70s (inactive)", appname);
+    newtitle = dupprintf("%s (inactive)", appname);
-    win_set_icon_title(wintw, morestuff);
+    win_set_icon_title(wintw, newtitle);
-    win_set_title(wintw, morestuff);
+    win_set_title(wintw, newtitle);
+    sfree(newtitle);
 
     if (ldisc) {
 	ldisc_free(ldisc);
@@ -1178,10 +1183,9 @@ static void wintw_set_raw_mouse_mode(TermWin *tw, bool activate)
  */
 static void win_seat_connection_fatal(Seat *seat, const char *msg)
 {
-    char title[100];
+    char *title = dupprintf("%s Fatal Error", appname);
-
-    sprintf(title, "%.70s Fatal Error", appname);
     MessageBox(hwnd, msg, title, MB_ICONERROR | MB_OK);
+    sfree(title);
 
     if (conf_get_int(conf, CONF_close_on_exit) == FORCE_ON)
 	PostQuitMessage(1);
@@ -1196,14 +1200,15 @@ static void win_seat_connection_fatal(Seat *seat, const char *msg)
 void cmdline_error(const char *fmt, ...)
 {
     va_list ap;
-    char *stuff, morestuff[100];
+    char *message, *title;
 
     va_start(ap, fmt);
-    stuff = dupvprintf(fmt, ap);
+    message = dupvprintf(fmt, ap);
     va_end(ap);
-    sprintf(morestuff, "%.70s Command Line Error", appname);
+    title = dupprintf("%s Command Line Error", appname);
-    MessageBox(hwnd, stuff, morestuff, MB_ICONERROR | MB_OK);
+    MessageBox(hwnd, message, title, MB_ICONERROR | MB_OK);
-    sfree(stuff);
+    sfree(message);
+    sfree(title);
     exit(1);
 }
 
@@ -5381,15 +5386,15 @@ static void wintw_clip_request_paste(TermWin *tw, int clipboard)
 void modalfatalbox(const char *fmt, ...)
 {
     va_list ap;
-    char *stuff, morestuff[100];
+    char *message, *title;
 
     va_start(ap, fmt);
-    stuff = dupvprintf(fmt, ap);
+    message = dupvprintf(fmt, ap);
     va_end(ap);
-    sprintf(morestuff, "%.70s Fatal Error", appname);
+    title = dupprintf("%s Fatal Error", appname);
-    MessageBox(hwnd, stuff, morestuff,
+    MessageBox(hwnd, message, title, MB_SYSTEMMODAL | MB_ICONERROR | MB_OK);
-	       MB_SYSTEMMODAL | MB_ICONERROR | MB_OK);
+    sfree(message);
-    sfree(stuff);
+    sfree(title);
     cleanup_exit(1);
 }
 
@@ -5399,14 +5404,15 @@ void modalfatalbox(const char *fmt, ...)
 void nonfatal(const char *fmt, ...)
 {
     va_list ap;
-    char *stuff, morestuff[100];
+    char *message, *title;
 
     va_start(ap, fmt);
-    stuff = dupvprintf(fmt, ap);
+    message = dupvprintf(fmt, ap);
     va_end(ap);
-    sprintf(morestuff, "%.70s Error", appname);
+    title = dupprintf("%s Error", appname);
-    MessageBox(hwnd, stuff, morestuff, MB_ICONERROR | MB_OK);
+    MessageBox(hwnd, message, title, MB_ICONERROR | MB_OK);
-    sfree(stuff);
+    sfree(message);
+    sfree(title);
 }
 
 static bool flash_window_ex(DWORD dwFlags, UINT uCount, DWORD dwTimeout)
@@ -5514,13 +5520,14 @@ static void wintw_bell(TermWin *tw, int mode)
 	Filename *bell_wavefile = conf_get_filename(conf, CONF_bell_wavefile);
 	if (!p_PlaySound || !p_PlaySound(bell_wavefile->path, NULL,
                          SND_ASYNC | SND_FILENAME)) {
-	    char buf[sizeof(bell_wavefile->path) + 80];
+            char *buf, *otherbuf;
-	    char otherbuf[100];
+            buf = dupprintf(
-	    sprintf(buf, "Unable to play sound file\n%s\n"
+                "Unable to play sound file\n%s\nUsing default sound instead",
-		    "Using default sound instead", bell_wavefile->path);
+                bell_wavefile->path);
-	    sprintf(otherbuf, "%.70s Sound Error", appname);
+            otherbuf = dupprintf("%s Sound Error", appname);
-	    MessageBox(hwnd, buf, otherbuf,
+            MessageBox(hwnd, buf, otherbuf, MB_OK | MB_ICONEXCLAMATION);
-		       MB_OK | MB_ICONEXCLAMATION);
+            sfree(buf);
+            sfree(otherbuf);
 	    conf_set_int(conf, CONF_beep, BELL_DEFAULT);
 	}
     } else if (mode == BELL_PCSPEAKER) {