C Integer Processing Program Overview

Text Explanation Analysis

The provided code is a C program that processes integers from an input file, optionally filters them, sorts them, and writes the result to an output file. The main components of the code include error handling, file operations, memory allocation, and basic sorting with a custom comparison function.

Visual Representation

Flowchart

           +----------------------+
           |      Start           |
           +----------+-----------+
                      |
                      v
           +----------+-----------+
           | Parse Command-line   |
           |    Arguments         |
           +----------+-----------+
                      |
                      v
           +----------+-----------+
           |  Validate Args Count |
           +----+-------+--------+
                |       |
                |       v
                | +-----+-------+
                | |   Errors:   |
                | | show_error  |
                | +-------------+
                |
                v
           +----+----------------+
           |  Open Input File    |
           +----+--------+-------+
                |        |
                |        v
                |   +----+-------+
                |   | Errors:    |
                |   | show_error |
                |   +------------+
                |
                v
           +----+-----------+-------------------+
           | Read Numbers  |   Count Numbers    |
           +----+-----------+-------------------+
                | 
                v
           +----+------------+------------------+
           |  Close Input File                  |
           |  Init Array / alloc mem for array  |
           +----+-----------+-------------------+
                |  
                v
           +----+----------------+
           |  Optional Filtering |
           +-----------+---------+
                       |
                       v
             +---------+---------+
             |  Sort the Array   |
             +---------+---------+
                       |
                       v
             +---------+---------+
             | Write to Output   |
             |      File         |
             +---------+---------+
                       |
                       v
                +------+-------+
                | Show Errors  |
                | if any       |
                +------+-------+
                       |
                       v
                +------+-------+
                |    End       |
                +--------------+

Pseudocode

MAIN FUNCTION:
1. Start
2. Parse command-line arguments
   a. If argc < 3, set error code to ERR_ARGS and go to END
   b. If argc == 4 and argv[3] == "f", set filter_mode to 1
3. Get input (file_in) and output file paths (file_out)
4. Call init_array() to load data from file_in
   a. If error, go to END
5. If filter_mode is enabled:
   a. Call key() to filter data
   b. Free the initial array memory if key() is successful
   c. If error, go to END
   OTHERWISE:
   a. Set pb to start of array and pe to end of array
6. Call mysort() to sort the data
7. Call write_into_file() to save sorted data to file_out
   a. If error, go to END
8. Free memory allocated for the array
9. Display error messages if any
10. End

FUNCTION show_error_message(rc):
1. Switch on rc:
   a. ERR_ARGS: Print "Ошибка аргументов"
   b. ... (other error messages)

FUNCTION count_numbers(filepath, result):
1. Open file
   a. If error, return ERR_FILE
2. Read integers and count them
   a. If end of file, close file and return OK
   b. If error, close file and return ERR_INS

FUNCTION fill_array(filepath, a, count):
1. Open file
   a. If error, return ERR_FILE
2. Allocate memory for array
   a. If error, return ERR_ALLOC
3. Fill array with integers from file
4. Close file and return OK

FUNCTION init_array(filepath, count, arr):
1. Call count_numbers() and set count
   a. If error, return error code
2. If count == 0, return ERR_EMP
3. Call fill_array() to populate the array
   a. If error, return error code
4. Set arr to populated array and return OK

FUNCTION key(pb_src, pe_src, pb_dst, pe_dst):
1. Call count_filter() to count valid numbers
   a. If count == 0, return ERR_EMP
2. Allocate memory for filtered array
   a. If error, return ERR_ALLOC
3. Use fill_filter() to copy valid numbers
4. Set pb_dst and pe_dst to filtered array and return OK

FUNCTION count_filter(pb, pe):
1. Count integers while no negative number is found
2. Return count

FUNCTION fill_filter(pb_src, pe_src, arr):
1. Copy integers to arr while no negative number is found

FUNCTION swap(l, r, size):
1. Swap bytes of size size between l and r

FUNCTION cmp(one, two):
1. Compare two integers
   a. Return 1 if one > two, else return 0

FUNCTION mysort(ptr, count, size, cmp):
1. Perform a bidirectional bubble sort on array ptr of size count using cmp for comparison

FUNCTION write_into_file(filepath, ps, pe):
1. Open file
   a. If error, return ERR_FILE
2. Write integers to file
3. Close file and return OK

Enhanced Clarity through Annotations

• Error Handling: Clearly denote error codes and the corresponding error messages for easier understanding.
• Function Interaction: Show how functions are related and their sequence of calls in handling different tasks.
• Conditional Flow: Highlight decision points, especially for cases where optional filtering is applied.
• Memory Management: Explicitly mention memory allocation and deallocation points.
• File Operations: Clearly mark the steps involving file opening, reading, writing, and closing to show data flow.

This visualization seeks to make the program's flow and interactions clearer, providing a structured overview of the logic and data handling processes within the code. For further learning on data visualization and detailed explanations, interested individuals can explore courses on the Enterprise DNA Platform.