0x19. C - Stacks, Queues - LIFO, FIFO
C - Group project - Algorithm - Data structure
Monty Interpreter
A language interpreter made in the C programming language to manage stacks and queues (LIFO and FIFO).
The aim is to interpret Monty bytecodes files. #Monty is a language that aims to close the gap between scripting and programming languages.
General - Requirements
~ Allowed editors: vi, vim, emacs
~ All files will be compiled on Ubuntu 20.04 LTS using gcc, using the options -Wall -Werror -Wextra -pedantic -std=c89
~ All files should end with a new line
~ A README.md file, at the root of the folder of the project is mandatory
~ The code should use the Betty style & It will be checked using betty-style.pl and betty-doc.pl
~ Allowed to use a maximum of one global variable & the C standard library
~ No more than 5 functions per file
~ The prototypes of all functions should be included in header file called monty.h
~ Pushing header file should must
~ All header files should be include guarded
~ Tasks should accomplished in the order shown in the project
Data structures
~ For the project use this Data structures. Don’t forget to include them in header.
Compilation & Output
$ make
~ Code will be compiled this way:
$ gcc -Wall -Werror -Wextra -pedantic -std=c89 *.c -o monty
~ Any output must be printed on stdout
~ Any error message must be printed on stderr
~ Here is a link to a GitHub repository that could help you making sure your errors are printed on stderr
Tests
~ Strongly encourage us to work all together on a set of tests
The Monty language
~ Monty 0.98 is a scripting language that is first compiled into Monty byte codes (Just like Python).
~ It relies on a unique stack, with specific instructions to manipulate it. The goal of this project is to create an interpreter for Monty ByteCodes files.
Monty byte code files
~ Files containing Monty byte codes usually have the .m extension. Most of the industry uses this standard but it is not required by the specification of the language.
~ There is not more than one instruction per line. There can be any number of spaces before or after the opcode and its argument:
julien@ubuntu:~/monty$ cat -e bytecodes/000.m
push 0$
push 1$
push 2$
push 3$
pall $
push 4$
push 5 $
push 6 $
pall$
julien@ubuntu:~/monty$
~ Monty byte code files can contain blank lines (empty or made of spaces only, and any additional text after the opcode or its required argument is not taken into account:
julien@ubuntu:~/monty$ cat -e bytecodes/001.m
push 0 Push 0 onto the stack$
push 1 Push 1 onto the stack$
$
push 2$
push 3$
pall $
$
$
$
push 4$
$
push 5 $
push 6 $
$
pall This is the end of our program. Monty is awesome!$
julien@ubuntu:~/monty$
The monty program
~ Usage: monty file
~ where file is the path to the file containing Monty byte code
~ If the user does not give any file or more than one argument to your program, print the error message
USAGE: monty file, followed by a new line, and exit with the status EXIT_FAILURE
~ If, for any reason, it’s not possible to open the file, print the error message Error: Can't open file <file>, followed by a new line, and exit with the status EXIT_FAILURE
~ where <file> is the name of the file
~ If the file contains an invalid instruction, print the error message L<line_number>: unknown instruction <opcode>, followed by a new line, and exit with the status EXIT_FAILURE
~ where is the line number where the instruction appears.
~ Line numbers always start at 1
~ The monty program runs the bytecodes line by line and stop if either:
~ it executed properly every line of the file
~ it finds an error in the file
~ an error occured
~ If you can’t malloc anymore, print the error message Error: malloc failed, followed by a new line, and exit with status EXIT_FAILURE.
~ You have to use malloc and free and are not allowed to use any other function from man malloc (realloc, calloc, …)
opcode functionality
push add element to the 'top' of stack and 'end' of queue
push remove element from 'top' of stack and 'end' of queue
pall print every member of the structure
pint prints the member value at the top of stack
swap swaps the order of the 1st and 2nd elements in stack
add add top two member values
sub subtract the top element from the 2nd top element
div divide the 2nd element by the top element
mul multiply the top two elements of the stack
mod The remainder when the 2nd element is divided by the top element
comment There is the ability to parse comments found in bytecode ->'#'
pchar print character at the top of the stack
pstr print the character at the top of the stack
rotl moves element at the top to the bottom of the stack
rotr The bottom of the stack becomes the top
Stack
queue Toggles the doubly link list implementation style
nop opcode should do nothing
Example: $ cat opcodetestfile.m
push 1
push 2
push 3
pall
$ ./montyfile opcodetestfile.m
3
2
1
$
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
$ cat opcodetestfile.m
push 1
push 2
push 3
pall
rotl
pall
$./montyfile opcodetestfile.m
3
2
1
2
1
3
Exit Status
Exits with status EXIT_FAILURE
Compilation
All files were compiled on Ubuntu 14.04 LTS
All programs and functions were compiled with gcc using flags -Wall -Wextra -Werror & =pedantic
Styling All files have been written in the betty style
Authors:
Ebsau Adem - [ebsaumar200@gmail.com]
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