Added readline support for linux/osx

Makefile

@@ -10,12 +10,12 @@ EXENAME = mcrcon
 PREFIX ?= /usr/local
 
 INSTALL = install
-LINKER =
+LINKER = -lreadline
 RM = rm -v -f
 
 CC = gcc
-CFLAGS = -std=gnu99 -Wall -Wextra -Wpedantic -Os -s
-EXTRAFLAGS ?= -fstack-protector-strong
+CFLAGS = -std=gnu99 -Wall -Wextra -Wpedantic -Os -s 
+EXTRAFLAGS ?= -fstack-protector-strong 
 
 ifeq ($(OS), Windows_NT)
 	LINKER = -lws2_32

mcrcon.c

@@ -45,6 +45,8 @@
     #include <netinet/in.h>
     #include <arpa/inet.h>
     #include <netdb.h>
+    #include <readline/readline.h>
+    #include <readline/history.h>
 #endif
 
 #define VERSION "0.7.1"
@@ -76,6 +78,8 @@ typedef struct _rc_packet {
 // Network related functions
 #ifdef _WIN32
 void        net_init_WSA(void);
+char        *readline( const char *prompt );  // Substitute function for gnu readline
+void        add_history( const char *p );     // Ditto
 #endif
 void        net_close(int sd);
 int         net_connect(const char *host, const char *port);
@@ -100,6 +104,7 @@ int         rcon_auth(int sock, char *passwd);
 int         rcon_command(int sock, char *command);
 
 
+
 // =============================================
 //  GLOBAL VARIABLES
 // =============================================
@@ -565,14 +570,20 @@ rc_packet *packet_build(int id, int cmd, char *s1)
 
 	// size + id + cmd + s1 + s2 NULL terminator
 	int s1_len = strlen(s1);
-	if (s1_len > DATA_BUFFSIZE) {
+
+        /* If s1_len == DATA_BUFSIZE pascket.data will not be null terminated
+         * This will cause a problem in packet_printf (maybe other places)
+         * This should probably be s1_len >= DATA_BUFFSIZE and explicitly
+         * null terminate packet.data to be safe */
+        if (s1_len > DATA_BUFFSIZE) {
 		fprintf(stderr, "Warning: Command string too long (%d). Maximum allowed: %d.\n", s1_len, DATA_BUFFSIZE);
 		return NULL;
 	}
 
 	packet.size = sizeof(int) * 2 + s1_len + 2;
 	packet.id = id;
 	packet.cmd = cmd;
+
 	strncpy(packet.data, s1, DATA_BUFFSIZE);
 
 	return &packet;
@@ -648,22 +659,31 @@ int run_commands(int argc, char *argv[])
 int run_terminal_mode(int sock)
 {
 	int ret = 0;
-	char command[DATA_BUFFSIZE] = {0x00};
 
 	puts("Logged in. Type 'quit' or 'exit' to quit.");
 
+        char *command = NULL;
 	while (global_connection_alive) {
-		putchar('>');
-		int len = get_line(command, DATA_BUFFSIZE);
 
+                command = readline( "> " );
+                if ( command == NULL )
+                        break;
+
+                /* Note that if len is > DATA_BUFFSIZE this will cause a non fatal
+                 * Error in build_packet */
+                size_t len = strlen( command );
+                if ( len ) {
+                        add_history( command );
+                }
+
 		if ((strcasecmp(command, "exit") && strcasecmp(command, "quit")) == 0)
 			break;
 
 		if(command[0] == 'Q' && command[1] == 0)
-			break;
+                        break;
 
 		if(len > 0 && global_connection_alive)
-			ret += rcon_command(sock, command);
+                        ret += rcon_command(sock, command);
 
 		/* Special case for "stop" command to prevent server-side bug.
 		 * https://bugs.mojang.com/browse/MC-154617
@@ -672,36 +692,58 @@ int run_terminal_mode(int sock)
 		 *       ensure compatibility with other servers using source RCON.
 		 * NOTE: strcasecmp() is POSIX function.
 		 */
-		if (strcasecmp(command, "stop") == 0) {
-			break;
-		}
+		if (strcasecmp(command, "stop") == 0 )
+                        break;
 
-		command[0] = len = 0;
+                free(command);
+                command = NULL;
+                len = 0;
 	}
 
+        if ( command != NULL ) {
+                free(command);
+        }
+
 	return ret;
 }
 
+
+#ifdef _WIN32
+void add_history( const char *p ) { }
+
 // gets line from stdin and deals with rubbish left in the input buffer
-int get_line(char *buffer, int bsize)
+char *readline( const char *prompt )
 {
-	char *ret = fgets(buffer, bsize, stdin);
-	if (ret == NULL)
-		exit(EXIT_FAILURE);
+        size_t bsize = DATA_BUFFSIZE;
+
+        fputs(prompt, stdout);
+
+        char *buffer = malloc( bsize );
+        if ( buffer == NULL ) {
+                fprintf( stderr, "Could not allocate memory for read buffer\n" );
+                exit(EXIT_FAILURE);
+        }
+
+        char *ret = fgets(buffer, bsize, stdin);
+	if (ret == NULL) {
+                free(buffer);
+                exit(EXIT_FAILURE);
+        }
 
 	if (buffer[0] == 0)
 		global_connection_alive = 0;
 
 	// remove unwanted characters from the buffer
 	buffer[strcspn(buffer, "\r\n")] = '\0';
 
-	int len = strlen(buffer);
+	size_t len = strlen(buffer);
 
 	// clean input buffer if needed 
 	if (len == bsize - 1) {
 		int ch;
 		while ((ch = getchar()) != '\n' && ch != EOF);
 	}
 
-	return len;
+	return buffer;
 }
+#endif