CS 2734 Programming Project: MAC-1 Assembler

• The assembler is to be written in C. You are to use fgets and strtok in the parsing of the tokens.

• The assembler takes the following command-line options:
  -o filename1
  -s filename2
  

  If -o is given, the assembler writes the assembled code to filename1, otherwise the assembler writes the assembled code to a.out. If -s is given, the assembler writes the symbol table in ASCII to filename2. The assembled code should be written out in ASCII hex.

• The assembler should be a two pass-assembler. In the first pass the assembler creates a symbol table and outputs it if the -s option was given on the command line. In the second pass the assembler assembles the code and outputs it to the appropriate file.

• You may assume for this assignment that no program will ever contain more than 100 symbols. You may use an array for the symbol table.

• Your program should be well-structured and well-documented. Each function should have a header describing the function and specifying the meaning of each parameter.

• Your assembler should recognize the .WORD directive for defining memory locations. For example,
  

  .WORD 6

  means to set aside 6 memory locations and set the values contained in these locations to zero.

• You may assume that all opcodes and the .WORD directive are in upper case. If an operand contains only valid decimal digits, it is assumed to be a value. Use atoi to convert it from string to an int. Otherwise an operand is assumed to be a label. Label definitions are on lines by themselves and end in a colon. Write a function is_string_a_number to determine whether a string only contains valid decimal digits.

• If your assembler encounters invalid assembly language, it should print an appropriate error message and exit. On the final test, you will be asked to demonstrate your assembler for many different test programs.

Due Dates:

Note: You must hand in completely documented source code for each part by midnight on the Wednesday of the due week.