Description
Write a complete module used to maintain the symbol table for the SIC/XE assembler:
• use a binary search tree implementation to store each symbol along with its associated attributes
o exportable binary search tree operations: insert, search, view (create, destroy – non-class based)
Write a complete main/driver program that uses the symbol table module to process two text files:
• SYMBOLS.DAT used to populate the symbol table.
o file format (each line): SYMBOL VALUE RFLAG
▪ zero or more leading spaces in front of the SYMBOL attribute.
▪ one or more leading spaces in front of the VALUE and RFLAG attributes.
• search file used to search the symbol table.
o search file name obtained from the command line.
o file format (each line): SYMBOL
▪ zero or more leading spaces in front of the SYMBOL attribute.
Basic Algorithm
1. read symbols and their attributes one line at a time from the file named SYMBOLS.DAT.
o invalid symbols and/or invalid symbol attributes are not inserted in the symbol table.
▪ display the symbol along with a detailed error message.
o valid symbols with valid attributes are inserted in the symbol table.
2. read symbols one at a time from the search file.
o if no file name was specified on the command line then prompt the user for the file name.
o invalid symbol: display the symbol along with a detailed error message.
o valid symbol: search for the symbol in the symbol table (significant portion only).
▪ found: display the symbol and its associated attributes.
▪ not found: display the symbol along with a detailed error message.
3. perform an inorder traversal of the symbol table.
o display all symbols and associated attributes in a tabular format using output formatting techniques.
SYMBOL (also referred to as a label in assembly language programing)
• starts with a letter (A..Z, a..z).
• followed by letters (A..Z, a..z), digits (0..9), and the dash (-).
• maximum of 10 characters in length in the source program
o only the first 5 characters are significant.
o only the first 5 characters are stored in the symbol table.
• not case sensitive (CSC-354, CSc-354, csc-354 – all the same symbol – stored as CSC-3).
VALUE
• signed integer value (+, –, 0..9).
RFLAG (Boolean)
• 0, f, false
• 1, t, true
• not case sensitive.
IFLAG (Boolean)
• indicates whether or not a symbol has been defined within the current control section – (true for now).
MFLAG (Boolean)
• indicates whether or not a symbol has been defined more than one time in the same control section.
• each valid symbol is inserted into the symbol table exactly one time (invalid symbols are never inserted).
Sample Program Run
Step #1 – SYMBOLS.DAT // File names are case sensitive in Linux as well as some languages
ABCDE 50 True // Valid – insert ABCDE and all attributes into symbol table (*)
B12-34 -3 false // Valid – insert B12-3 and all attributes into symbol table (*)
a1B2-c3-D4 +45 1 // Valid – insert A1B2- and all attributes into symbol table (*)
ABCD! 33 t // ERROR – symbols contain letters, digits and dashes: ABCD!
1234567890 0 0 // ERROR – symbols start with a letter: 1234567890
ABCDEF +100 1 // ERROR – symbol previously defined: ABCDE (+)
a1234 3.5 F // ERROR – symbol a1234 invalid value: 3.5
XYZ 100 5 // ERROR – symbol XYZ invalid rflag: 5
(*) no message displayed for valid symbols with valid attributes – set IFLAG to true – set MFLAG to false
(+) set MFLAG attribute to true for symbol ABCDE
Step #2 – search file
ABCDE // Found – display symbol ABCDE and all attributes
A1b2-C3xYz // Found – display symbol A1B2- and all attributes
CDEF // ERROR – CDEF not found in symbol table
abc_def // ERROR – symbols contain letters, digits and dashes: abc~def
a1b2c3d4e5f6 // ERROR – symbols contain 10 characters maximum: a1b2c3d4e5f6
Step #3 – view the symbol table – required output order and format
Symbol Value RFlag IFlag MFlag // Do not allow the data to scroll off of the screen
// Hold the output every 20 lines – Tera Term screen size
A1B2- 45 1 1 0 // Continue when user indicates to do so
ABCDE 50 1 1 1
B12-3 -3 0 1 0 // Perform an in-order traversal of symbol table
Notes and Suggestions
• Do NOT stop on error!!! Process all data in both files completely!!! Display detailed error messages!!!
• Check for errors in all symbols and all symbol attributes read from both files
o Step #1 SYMBOL VALUE RFLAG
o Step #2 SYMBOL
• Convert all values to one common format:
o All symbols were converted to uppercase: csc, CSC, CSc => CSC
o All flag values were converted to Boolean values: 0, f, false => 0 1, t, true => 1
Other Requirements
• The module/program must use proper data abstraction techniques.
o See the Assignment Requirements document on the course web site.
• All module/program files must be fully documented.
o See the Documentation Requirements document on the course web site.
• All C/C++ programs must compile and run using the Computer Science Linux server: cscssh.sdstate.edu
• All C# programs must compile and run as a Visual Studio 2017 Community Edition solution/project.
• All Java programs must compile and run from the command line. Include Instructions for building/running
with your program submission.
• Zip all files together and send them to the account listed one the course syllabus before class on the due
date.
o Visual Studio zip entire solution folder (containing project folder)
o Java zip entire project folder
o C/C++ zip all necessary program and header files.
• All duplicate or near duplicate assignments will earn a grade of 0.
