Introduction$$ In this case study you will implement a simple logging service built on top of a message queue.$2$ Specification$$The task is broken into two parts, a message logging server, and a library to log messages. The$$message server listens to a message queue and extracts the log messages from it$.$ The library$$provides a more convenient way access the message queue.$$You have been provided with a program to test that your library communicates with your$$server$.$ You will need to review the lecture notes, and the documentation supplied in Section $4$to implement these programs.$2\mathrm{.}1$ Message Logging Server$$The message logging server should attempt to create the message queue, if this fails then it$$should terminate with an error message, it should not run if the message queue actually exists$($IPC$\_$EXCL will help here$).$Once connected to the message queue, the program should sit in a loop, receiving a mes$-$sage$,$ and printing it to the stdout. Messages should be formatted:$$id: message$$where id is the type from the message structure and message is the message field.$$The server should shutdown cleanly $($i$.$e$.$ delete the message queue$)$ on receipt of a SIGINT$($generated by pressing control and C keys at the same time$).$The sample code files logservice$.$h and logserver$.$c should form the basis of$$your solution for this part. There are a number of comments in this file to help you structure$$your code.$2\mathrm{.}2$ Messaging library$$The messaging library consists of two functions, both defined in logservice$.$h:$$int initLogService$()$This function should initialise the message queue to log messages to$,$ returning$$an id if successful, and $-1$ on error.$$This function should not attempt to create the message queue, only attach it to$$the process

int logMessage$($int id$,$ char $*$message$)$This function logs the message passed as the string message to the log$$service id$.$ It should return $0$ on success and $-1$ on error.$$When sending a message, the function should encode the processes pid into$$the type field of the message, and the string into the message field.$$It is your choice what to do if the message is too long $($i$.$e$.$ longer than$$MSGCHARS$),$ sample behaviours include breaking the message up into$$smaller pieces or simply rejecting it$.$ Whatever the choice, the documentation in$$the header file should reflect this choice.$$The sample code files logservice$.$h and logservice$.$c should form the basis of$$your solution for this part.$3$ Sample Code$$In addition to the sample code files, two additional files have been provided, a makefile$$that contains build rules, and a server launch script.$$The make utility simplifies the build process for large projects, introductory documen$-$tation for make is included in the documentation section $($Sec$.4).$ To use make to auto$-$mate compile process simply type $$make$$ at the terminal $($in the same directory as the other$$files$),$ it will use the rules defined in the makefile to build both the logserver and$$logclient executables from the source files, and it will also ensure that the$$launch server.sh script is executable. If none of the source files have changed since$$the last build $($based on their timestamps$)$ the make utility will not rebuild the executables.$$There should be no need to modify the makefile, its format is a bit fussy so it is safer to$$download the file from vUWS than type it up$.$The launch server.sh script will open the logserver program in a new termi$-$nal window for you. This script detects the host operating system and performs an equivalent$$action after this detection. There is nop need to understand how this file achieves its goal. $3\mathrm{.}1$ logservice$.h3\mathrm{.}2$ logservice$.$c $3\mathrm{.}3$ logclient$.$c $3\mathrm{.}4$ logserver$.$c$3\mathrm{.}5$ makefile

$3\mathrm{.}6$ launch$\_$server.sh