declare default port as int, use HOST_NAME_MAX

src/atcmd.c

@@ -81,7 +81,7 @@ m2k_atcmdD(const char *s, AtdAType at, AtdPType pt)
   if (*s == '"')
     s++;
   /* "%[^:\"]:%[^\"]" */
-  sscanf(s, "%" LIT(ADDR_MAX) "[^ \"] %" LIT(PORT_MAX) "[^\"]",
+  sscanf(s, "%" LIT(HOST_NAME_MAX) "[^ \"] %" LIT(PORT_MAX) "[^\"]",
          atcmd.d.addr.str, atcmd.d.port.str);
   atcmd.d.addr.type = at;
   atcmd.d.port.type = pt;

src/modemu2k.h

@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2018 Andy Alt <[email protected]>
+ * Copyright 2022 Andy Alt <[email protected]>
  *
  * modemu2k is a fork of modemu
  * Originally developed by Toru Egashira
@@ -29,11 +29,13 @@
  * @brief core modemu2k API
  */
 
+#include <limits.h>
 #include <stdio.h>              /*stderr,(sscanf,sprintf) */
 #include <string.h>             /*(strncpy) */
 #include <stdbool.h>
 #include <sys/types.h>
 #include <sys/time.h>
+#include <unistd.h>
 
 #ifdef TERMNET
 #include <termnet.h>
@@ -47,6 +49,10 @@
 
 #include "cmdarg.h"
 
+#ifndef HOST_NAME_MAX
+#define HOST_NAME_MAX 255
+#endif
+
 /* TODO: the API shouldn't be localized and really shouldn't contain any strings;
  * but rather the functions should return values to the application can print
  * any messages to stdout or stderr
@@ -76,7 +82,7 @@ typedef unsigned char uchar;
 #define HAVE_GRANTPT
 #endif
 
-#define DEFAULT_PORT 23
+extern const int DEFAULT_PORT;
 
 // sock
 
@@ -123,7 +129,6 @@ typedef enum
   ATDP_STR
 } AtdPType;
 
-#define ADDR_MAX 63
 #define PORT_MAX 63
 #define PT_MAX 40
 #define SREG_MAX 12
@@ -134,7 +139,7 @@ typedef struct
   {
     struct
     {
-      char str[ADDR_MAX + 1];
+      char str[HOST_NAME_MAX + 1];
       AtdAType type;
     } addr;
     struct

src/sock.c

@@ -31,6 +31,8 @@
 #include <stdlib.h>             /*(getenv) */
 #include "modemu2k.h"
 
+const int DEFAULT_PORT = 23;
+
 void
 sockInit(struct st_sock *sock)
 {
@@ -65,36 +67,33 @@ sockShutdown(st_sock * sock)
 int
 m2k_sockDial(st_sock * sock)
 {
-  struct addrinfo hints;
+  struct addrinfo hints, *result;
   memset(&hints, 0, sizeof(struct addrinfo));
 
-  sockInit(sock);
-  struct addrinfo *result = NULL;
-
-  int s;
-
   hints.ai_family = AF_UNSPEC;  /* Allow IPv4 or IPv6 */
   hints.ai_socktype = SOCK_STREAM;
   hints.ai_flags = 0;
   hints.ai_protocol = 0;        /* Any protocol */
 
   char out_port[PORT_MAX + 1];
+  if ((size_t)
+      snprintf(out_port, sizeof out_port, "%d",
+               atcmd.d.port.type ==
+               ATDP_NUL ? DEFAULT_PORT : atoi(atcmd.d.port.str)) >=
+      sizeof out_port)
+    return 1;
 
-  if (atcmd.d.port.type == ATDP_NUL)
-    snprintf(out_port, sizeof out_port, "%d", DEFAULT_PORT);
-  else
-  {
-    strcpy(out_port, atcmd.d.port.str);
+  if (atcmd.d.port.type != ATDP_NUL)
     telOpt.sentReqs = 1;        /* skip sending option requests */
-  }
 
-  s = getaddrinfo(atcmd.d.addr.str, out_port, &hints, &result);
+  int s = getaddrinfo(atcmd.d.addr.str, out_port, &hints, &result);
   if (s != 0)
   {
     fprintf(stderr, _("Host address lookup failed: %s\n"), gai_strerror(s));
     return 1;
   }
 
+  sockInit(sock);
   for (sock->rp = result; sock->rp != NULL; sock->rp = sock->rp->ai_next)
   {
     sock->fd =