Don't call memcpy() if there is nothing to copy

- rename "flag_connection_alive" variable back to "global_connection_alive"
- return exit code from run_terminal_mode()
- rcon_command(): add error messages

.gitignore

@@ -2,5 +2,9 @@
 *.o
 *.dev
 *.win
+*.txt
 *.layout
 *.project
+mcrcon
+todo
+*.plist

BUILDING.md

@@ -0,0 +1,29 @@
+Building and installing
+-----------------------
+
+#### Requirements & dependencies:
+- GCC compatible compiler
+- POSIX getopt support from **<unistd.h>**
+
+---
+
+#### Compiling
+
+    cc -std=gnu99 -Wpedantic -Wall -Wextra -Wno-gnu-zero-variadic-macro-arguments -O2 -o mcrcon mcrcon.c
+    
+>[!NOTE]
+>If you are compiling on Windows remember to link with winsock by adding `-lws2_32` to your compiler command line.
+
+---
+
+Or you can run **make**
+
+    make           - compiles mcrcon
+    make install   - installs compiled binaries and manpage to the system
+    make uninstall - removes binaries and manpage from the system
+    
+    file install locations:
+        /usr/local/bin/mcrcon
+        /usr/local/share/man/man1/mcrcon.1
+
+Makefile **install** and **uninstall** rules are not available on Windows.

CHANGELOG.md

@@ -0,0 +1,93 @@
+#### Version history:
+
+###### 0.7.3
+ - Add support to Valve style rcon authentication
+ - Change maximum packet size to correct value (4096 -> 4106)
+ - Print auth failed message to stderr instead of stdout
+ - Fail immediately if received packet size is out of spec
+ - Return proper exit code from run_terminal_mode()
+ - Add error messages to rcon_command() function
+ 
+###### 0.7.2
+ - Quit gracefully when Ctrl-D or Ctrl+C is pressed
+ - Remove "exit" and "quit" as quitting commands
+    * these are actual rcon commands on some servers
+ - Suppress compiler warning (strncpy)
+ - Fix erroneous string length in packet building function
+ - Fix typo in ANSI escape sequence for LCYAN
+ - Make stdout and stderr unbuffered
+
+###### 0.7.1
+ - Deprecate `-i` flag for invoking terminal mode
+ - Add workaround to prevent server-side bug.
+   * https://bugs.mojang.com/browse/MC-154617
+
+###### 0.7.0
+ - Add -w option for rcon command throttling
+    * Thanks HorlogeSkynet @ Github
+
+###### 0.6.2
+ - Set default address to localhost
+
+###### 0.6.1
+ - Color coding fixed
+    * Thanks to Hagb @ Github
+
+###### 0.6.0
+ - Version numbering changed to more sane system (0.0.5 -> 0.6.0)
+ - Fixed munged output
+ - Support for using environment variables to set some basic options
+ - Cleaned networking code
+ - Various code cleanups
+ - Changes and updates in usage text and error reporting
+ - Version option flag (-v) added
+ - Man page added 
+ - Proper makefile added
+
+###### 0.0.5
+  - IPv6 support!
+     * Thanks to 'Tanja84dk' for addressing the real need of IPv6.
+
+  - Fixed bug causing crash / segmentation fault (invalid write) when receiving malformed rcon packet.
+
+  - Program makes use of C99 feature (variable-length arrays) so "-std=gnu99" flag on
+    GCC-compiler must be used to avoid unecessary warnings.
+
+  - Rcon receive buffer is now bigger (2024 bytes -> 10240 bytes).
+     * Thanks to 'gman_ftw' @ Bukkit forums.
+
+  - Fixed invalid error message when receiving empty rcon packet (10 bytes).
+     * Thanks to 'pkmnfrk' @ bukkit forums.
+
+  - Terminal mode now closes automatically when rcon socket is closed by server
+    or if packet size cannot be retrieved correctly.
+
+  - Client now tries to clean the incoming socket data if last package was out of spec.
+
+###### 0.0.4
+  - Reverted back to default getopts options error handler (opterr = 1).
+    Custom error handler requires rewriting.
+  - Some cosmetic changes in program output strings.
+  - Program usage(); function now waits for enter before exiting on Windows.
+
+###### 0.0.3
+  - Colors are now supported on Windows too!
+  - Terminal mode is now triggered with "-t" flag. "-i" flag still works for
+    backwards compatibility.
+  - Bug fixes (Packet size check always evaluating false and color validity
+    check always evaluating true).
+
+###### 0.0.2
+  - License changed from 'ISC License' to 'zlib/libpng License'.
+  - Bug fixes & code cleanups
+  - Interactive mode (-i flag). Client acts as interactive terminal.
+  - Program return value is now the number of rcon commmands sent successfully.
+    If connecting or authentication fails, the return value is -1.
+  - Colors are now enabled by default. Now '-c' flag disables the color support.
+
+###### 0.0.1
+  - Added experimental support for bukkit colors.
+    Should work with any sh compatible shell.
+  - Packet string data limited to max 2048 (DATA_BUFFSIZE) bytes.
+    No idea how Minecraft handles multiple rcon packets.
+    If someone knows, please mail me so I can implement it.

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2012-2013, Tiiffi <tiiffi --> gmail_dot_com>
+Copyright (c) 2012-2024, Tiiffi <tiiffi at gmail>
 
 This software is provided 'as-is', without any express or implied
 warranty. In no event will the authors be held liable for any damages

Makefile

@@ -0,0 +1,47 @@
+# if you want to cross compile:
+#   export PATH=$PATH:/path/to/compiler/bin
+#   export CROSS_COMPILE=arm-none-linux-gnueabi-
+#   make
+#
+# Windows cross compile:
+#   x86_64-w64-mingw32-gcc -std=gnu99 -Wall -Wextra -Wpedantic -O2 -fstack-protector-all -o mcrcon.exe mcrcon.c -lws2_32
+
+EXENAME = mcrcon
+PREFIX ?= /usr/local
+
+INSTALL = install
+LINKER =
+RM = rm -v -f
+
+CC ?= gcc
+CFLAGS = -std=gnu99 -Wall -Wextra -Wpedantic -Wno-gnu-zero-variadic-macro-arguments -O2
+EXTRAFLAGS ?= -fstack-protector-all
+
+ifeq ($(OS), Windows_NT)
+	LINKER = -lws2_32
+	EXENAME = mcrcon.exe
+	RM = cmd /C del /F
+endif
+
+.PHONY: all
+all: $(EXENAME)
+
+$(EXENAME): mcrcon.c
+	$(CROSS_COMPILE)$(CC) $(CFLAGS) $(EXTRAFLAGS) -o $@ $< $(LINKER)
+
+ifneq ($(OS), Windows_NT)
+.PHONY: install
+install:
+	$(INSTALL) -v $(EXENAME) $(DESTDIR)$(PREFIX)/bin/$(EXENAME)
+	$(INSTALL) -v -m 0644 mcrcon.1 $(DESTDIR)$(PREFIX)/share/man/man1/mcrcon.1
+	@echo "\nmcrcon installed. Run 'make uninstall' if you want to uninstall.\n"
+
+.PHONY: uninstall
+uninstall:
+	$(RM) $(DESTDIR)$(PREFIX)/bin/$(EXENAME) $(DESTDIR)$(PREFIX)/share/man/man1/mcrcon.1
+	@echo "\nmcrcon uninstalled.\n"
+endif
+
+.PHONY: clean
+clean:
+	$(RM) $(EXENAME) $(EXENAME).exe

README.md

@@ -1,10 +1,108 @@
-####Compiling:
+# mcrcon
 
-```gcc -std=gnu11 -pedantic -Wall -Wextra -O2 -s -o mcrcon mcrcon.c```
+mcrcon is a command-line [rcon](https://developer.valvesoftware.com/wiki/Source_RCON_Protocol) client intended for remote server administration and maintenance automation.
+
+Though originally developed for Minecraft servers, it also works with a variety of other servers using the Valve or Minecraft-style rcon protocol.
 
-On windows, remember to link with winsockets.
-Add ```-lws2_32``` to compiler command line on Mingw GCC.
 
 ---
 
-More info [here](http://forums.bukkit.org/threads/admin-rcon-mcrcon-remote-connection-client-for-minecraft-servers.70910/).
+### Installing
+
+##### Binary releases
+
+Pre-built binaries are provided for Linux and Windows: https://github.com/Tiiffi/mcrcon/releases/latest
+
+##### Via package manager
+See https://pkgs.org/download/mcrcon and https://repology.org/project/mcrcon/packages for available packages in various Linux distros (note that some packages might be outdated).
+
+- Fedora: https://packages.fedoraproject.org/pkgs/mcrcon/mcrcon/
+- Gentoo: https://packages.gentoo.org/packages/games-util/mcrcon
+- Arch: https://aur.archlinux.org/packages/mcrcon/
+- NixOS: https://search.nixos.org/packages?show=mcrcon
+- Snapcraft: https://snapcraft.io/mcrcon-nsg
+- Scoop: https://scoop.sh/#/apps?q=mcrcon
+
+##### Building from sources
+```sh
+git clone https://github.com/Tiiffi/mcrcon.git
+cd mcrcon
+make
+
+# install is optional
+sudo make install
+```
+_Check [BUILDING.md](BUILDING.md) for more details._
+
+---
+
+### Usage
+mcrcon [OPTIONS] [COMMANDS]
+
+Sends rcon commands to Minecraft server.
+
+```
+Option:
+  -H            Server address (default: localhost)
+  -P            Port (default: 25575)
+  -p            Rcon password
+  -t            Terminal mode
+  -s            Silent mode
+  -c            Disable colors
+  -r            Output raw packets
+  -w            Wait for specified duration (seconds) between each command (1 - 600s)
+  -h            Print usage
+  -v            Version information
+```
+Server address, port and password can be set using following environment variables:
+```
+MCRCON_HOST
+MCRCON_PORT
+MCRCON_PASS
+```
+###### Notes:
+- mcrcon will start in terminal mode if no commands are given
+- Command-line options will override environment variables
+- Rcon commands with spaces must be enclosed in quotes
+
+###### Example:
+Send three commands ("say", "save-all", "stop") and wait five seconds between the commands:
+
+```sh
+mcrcon -H my.minecraft.server -p password -w 5 "say Server is restarting!" save-all stop
+```
+---
+
+> [!TIP]
+>Enable RCON on Minecraft server by adding following lines to [```server.properties```](https://minecraft.gamepedia.com/Server.properties) configuration file.
+>```
+>enable-rcon=true
+>rcon.port=25575
+>rcon.password=your_rcon_pasword
+>```
+
+---
+
+### Contact
+
+* WWW:            https://github.com/Tiiffi/mcrcon/
+* MAIL:           tiiffi+mcrcon at gmail
+* ISSUES:         https://github.com/Tiiffi/mcrcon/issues/
+
+> [!TIP]
+>When reporting issues, please provide the following information:
+>
+>- Version of mcrcon: Please specify the precise version number
+>- Game: Indicate the specific game server you're using (e.g., Minecraft, Valve Source Engine game, ARK, ...)
+>- Server version: Provide the exact version of the game server
+>- Mods and Extensions: List all mods and extensions used, including their versions
+>- Issue Description: Clearly describe the problem you're encountering and the expected behavior.
+>- Steps to reproduce
+>
+>If you're tech-savvy, consider providing a packet capture file (PCAP). Remember to use a fake password.
+
+---
+
+### License
+
+This project is licensed under the zlib License - see the [LICENSE](LICENSE) file for details.

create_shortcut.bat

@@ -0,0 +1,31 @@
+@echo off
+@cls
+
+@set /p host="Enter host (default: "127.0.0.1"): "
+@if "%host%"=="" set host=127.0.0.1
+
+@set /p port="Enter port (default: 25575): "
+@if "%port%"=="" set port=25575
+
+@set /p passwd="Enter password: "
+@if "%passwd%"=="" set passwd=
+
+set name=connect_%host%-%port%
+
+@set /p name="Enter shortcut name (default: "%name%.bat"): "
+@if "%name%"=="" set name=connect_%host%-%port%
+
+set command=@mcrcon.exe -t -H %host% -P %port% -p %passwd%
+
+@echo %command% >> %name%.bat
+@echo.
+@echo Command: "%command%"
+@echo.
+@echo Shortcut "%name%.bat" created!
+@echo.
+
+@set "host="
+@set "port="
+@set "passwd="
+
+@pause

launch.bat

@@ -0,0 +1,29 @@
+@echo off
+@cls
+
+@if not exist mcrcon.exe (
+  @echo ERROR: Cannot find "mcrcon.exe". Bailing out!
+  @echo.
+  @pause
+  @exit
+)
+
+@set /p host="Enter host (default: 127.0.0.1): "
+@if "%host%"=="" set host=127.0.0.1
+
+@set /p port="Enter port (default: 25575): "
+@if "%port%"=="" set port=25575
+
+@set /p passwd="Enter password: "
+@if "%passwd%"=="" set passwd=
+
+@echo.
+mcrcon.exe -t -H %host% -P %port% -p %passwd%
+@echo.
+
+@set "host="
+@set "port="
+@set "passwd="
+
+@pause
+

mcrcon.1

@@ -0,0 +1,66 @@
+.\" Process this file with
+.\" groff -man -Tascii mcrcon.1
+.\"
+.TH MCRCON 1 "November 2024" "Version 0.7.3"
+.SH NAME 
+mcrcon \- send rcon commands to a Minecraft server
+.SH SYNOPSIS
+.B mcrcon [
+options
+.B ] [
+commands
+.B ]
+.SH DESCRIPTION
+mcrcon is a command-line rcon client intended for remote server administration and maintenance automation.
+.SH OPTIONS
+.IP -H
+Server address (default: localhost)
+.IP -P
+Port (default: 25575)
+.IP -p
+Rcon password
+.IP -t
+Terminal mode
+.IP -s
+Silent mode
+.IP -c
+Disable colors
+.IP -r
+Output raw packets
+.IP -w
+Wait for specified duration (seconds) between each command (1 - 600s)
+.IP -h
+Print usage
+.IP -v
+Output version information
+.PP
+Commands with spaces must be enclosed in quotes.
+.br
+mcrcon will start in terminal mode if no commands are given.
+.SH ENVIRONMENT VARIABLES
+Server address, port and password can be set with following environment variables:
+.PP
+\fBMCRCON_HOST
+.br
+\fBMCRCON_PORT
+.br
+\fBMCRCON_PASS\fR
+.PP
+Note that command-line options will override environment variables.
+.SH EXAMPLES
+Make rcon connection in terminal mode using default port
+.RS
+\fBmcrcon\fR -H my.minecraft.server -p password
+.RE
+.PP
+Send "weather clear" command to server using custom port 1337
+.RS
+\fBmcrcon\fR -H my.minecraft.server -P 1337 -p password "weather clear"
+.RE
+.PP
+Send three commands ("say", "save-all", "stop") and wait five seconds between the commands.
+.RS
+\fBmcrcon\fR -H my.minecraft.server -p password -w 5 "say Server is restarting!" save-all stop
+.RE
+.SH BUGS
+Report bugs to \fBtiiffi+mcrcon at gmail\fR or \fBhttps://github.com/Tiiffi/mcrcon/issues/\fR