Agent Work: Word Count

Claude Sonnet 4.6 · COMP 321: Introduction to Computer Systems

COMP 321: Introduction to Computer Systems

Project 2: Word Count

Overview

You will write C code to implement a program that counts the number of characters, words, and lines in a file. The goals of this project are as follows:

Use C pointers and data structures.
Allocate and deallocate memory.
Use C's Standard I/O library to read from files.
Become comfortable with writing a larger C program.

Summary

You will write a simplified version of the Unix "wc" word count program. Your count program must do the following:

Process multiple files.
Count the number of characters, words, and lines in each file.
Keep track of the total number of characters, words, and lines in all files.
Print the results for each file in "ASCIIbetical" order by file name.
Print the total number of characters, words, and lines in all files.

The program accepts three command line flags that control what it counts: "-c", "-w", and "-l". The flags indicate whether or not the program should count characters, words, and lines, respectively. Your program should support any combination of these flags. If no flags are specified, then nothing should be counted, but empty results for each file should still be printed.

We provide a main routine that reads and parses the command line arguments appropriately. The usage of the word count program is as follows:

count [-c] [-l] [-t] [-w] <input filenames>

The "-t" flag is for testing purposes. At least one input file must be specified on the command line. Otherwise, the main routine prints an error message and terminates the program. The main routine does not impose a limit on the number of input files, aside from the implied limit of INT_MAX because argc is of int type.

The main routine will call the following function based on what is specified on the command line:

static int
do_count(char *input_files[], const int nfiles,
    const bool char_flag, const bool word_flag,
    const bool line_flag, const bool test_flag)

The first argument, input_files, is an array of strings. Each string is the name of a file that should be counted. The second argument, nfiles, indicates how many elements are in the input_files array. The remaining "flag" arguments are true or false based on whether the corresponding options were specified on the command line. In other words, char_flag is true if the command line included -c and false otherwise. You may execute whatever testing code you would like when test_flag is true. When grading your submission, we will never specify -t on the command line, so this option is solely for your use.

Your do_count function should count the characters, words, and/or lines, based on the value of the flags, in each file specified in the input_files array. Once complete, the results should be printed out to stdout using the following provided function:

static void
print_counts(FILE *fp, struct counts *cnts,
    const char *name, const bool char_flag,
    const bool word_flag, const bool line_flag)

This will print out the results of counting a single file on one line. If all flags are true, it will print the number of lines, then the number of words, then the number of characters, and finally the (file) name. For each flag that is false, that count will be omitted, but everything else will remain in its respective order. The name is always printed. For each file, you should use the same values for the flags that were passed to do_count.

The results should be printed out in "ASCIIbetical" order based on the filename. Essentially, ASCIIbetical ordering collates strings based upon the numerical ASCII representation of the characters. It differs from the conventional notion of "alphabetical" ordering in that all upper-case letters come before all lower-case letters. For example, in ASCIIbetical ordering, the string "XYZ" will come before the string "abc". The function strcmp() can be used to help sort strings in this order. See man strcmp for details.

After all of the individual file results have been printed, a total should be printed. And, to be clear, a total should be printed regardless of the number of individual file results printed. The print_counts function should again be used, but the filename should be specified as "total" and the character, word, and line counts should all be printed, regardless of the command line options. If an option was not specified on the command line, the corresponding output in the total line should be 0.

For example:

./count -l file.txt abc.txt
    32 abc.txt
   254 file.txt
   286       0       0 total

Note that the return type of do_count is int. The value returned by your do_count function will subsequently be returned by the main routine, so your do_count function should follow the standard Unix convention for the return value from programs: return 0 if there were no errors and an integer between 1 and 255 otherwise. In other words, if there is an error opening or processing *any* of the files, then the return value from do_count should be an integer between 1 and 255. However, your do_count function should *not* stop opening and processing files just because it encounters an error. Instead, it should move on to the next file in the input_files array. Further details on handling errors are discussed below.

For the purposes of this assignment, you should use the following definition of characters, words, and lines:

Character: A character is any ASCII character that appears in a file, whether it is visible or not.
Word: A word is a sequence of ASCII characters separated by whitespace. Therefore, a word is any sequence of characters that does not include a character for which the function isspace returns true (see man isspace for further details on this function).
Line: A line is anything that ends with a '\n' character.

For example, consider the following input file:

This is a line.
This is another line.

This file has 38 characters, 8 words, and 2 lines. This is assuming that both lines end with a '\n' character, that there are no other whitespace characters (space, tab, etc.) at the end of either line, and that there are no other non-visible characters in the file.

You may write whatever additional procedures or data structures you deem necessary to complete this project, but they should all be contained within the count.c file.

Since a pedagogical goal of this assignment is that you allocate and deallocate memory, you may not add any additional arrays into your submitted count.c file beyond what's initially provided in the template. This restriction includes both fixed-length arrays and C99 variable-length arrays. Moreover, you may not make changes to the existing arrays.

While the computations performed by your do_count function on each file should take little time, reading the contents of each file will be a comparatively slow operation. Therefore, you may not open a file more than once or read the contents of a file more than once. In other words, you must simultaneously compute the requested character, word, and line counts in a single pass through each file.

If you encounter an error with a file that prevents the program from opening the file, you should use app_error_fmt to print out the following error message to stderr:

ERROR: cannot open file '<fname>'

If you encounter an error while reading the file that prevents the program from counting characters/words/lines, you should use app_error_fmt to print out the following error message to stderr:

ERROR: cannot read file '<fname>'

In the error messages, <fname> *must* be the file name, and that file name *must* be surrounded by single quotes (ASCII character 39). For example, if an error was encountered while trying to open the file /usr/share/dict/words, the following error message should be printed:

ERROR: cannot open file '/usr/share/dict/words'

Do not include a newline in the arguments that you pass to app_error_fmt, as app_error_fmt itself outputs the required newline at the end of the error message. These messages should be printed to stderr in the order in which the files occur in the input_files array passed to do_count (in contrast to the counts, which should be printed to stdout in ASCIIbetical order by filename). When such an irrecoverable error occurs, you should not print anything to stdout for that file and no counts from that file should be included in the total counts. Even if all files cause errors, the total line should still be printed.

Notes

Important: be sure to read this *entire* assignment handout carefully. Part of the point of this assignment is to ensure that you can follow an English language specification of a program precisely. This means that the output of your program must match the specifications of this handout exactly. *Do not modify the function print_counts, create your own output format, or add any additional output beyond what is specified in this handout.* You may want to add additional output while you are debugging your program, but be sure this debugging output only prints when the -t flag is specified or that you comment out (or remove) the debugging printouts before you are done.

Given this requirement, your program will be graded by performing exact matching on the output of your program and the correct output. You will receive no credit for every test that is run in which your program's output deviates from the formatting described above in any way. This includes both the counts and the error messages.

Before you concern yourself with sorting the output, we suggest that you first get your word count program working correctly with a single file. The program you are creating is analogous to the Unix wc program. For files containing only ASCII characters, wc reports the counts as required for this assignment, but it does not sort the output or always print the total line, which is required for this assignment.

The definition of a word that we specified in this assignment is the definition given by the applicable standards from the Open Group and IEEE defining how the wc program should behave: http://pubs.opengroup.org/onlinepubs/9699919799/utilities/wc.html

Note that you cannot assume anything about what will be in the input file(s) except that they will not contain any non-ASCII characters. You should not, for example, assume that the input files will only contain words less than 10 characters long or anything like that.

You will find the functions strcmp and isspace useful. See their man pages for details.

Three functions from the code described throughout the textbook, and provided in the files csapp.h and csapp.c, may be helpful in this project to simplify error handling:

void *Malloc(size_t size);
void Free(void *ptr);
void app_error(char *msg);

The Malloc and Free functions are wrappers around their lowercase counterparts that print an error message and terminate the program if they fail. Keep in mind that this may not always be the behavior you want. For example, if malloc fails, it means there is not enough memory in the system, so a smart program may be able to free up memory or use an alternative routine in that case. For this project, however, terminating the program is a reasonable response to out-of-memory errors. The procedure app_error simply prints the provided error message and terminates the program, which is useful whenever you encounter an unrecoverable error in your code. These functions will be compiled into your program automatically by the provided Makefile.

An additional function is provided in count.c:

static void app_error_fmt(char *fmt, ...);

This function takes the same arguments as printf. It will format and print the error message appropriately to stderr. It adds the string "ERROR: " to the front of the message and it adds a newline at the end. Unlike app_error, it does not terminate the program. This function should be used to report errors encountered during the processing of a file. You can then go on to process the next file in the array.

Files

You should see the following files in your workspace:

count.c - provided code (implement your solution here)
Makefile - specification for building count using make
writeup.md - a skeleton writeup file
instructions.md - this file
lib/ - symlink to csapp library (csapp.h, csapp.c)

Building Your Program

To build the program, use the Unix command:

make

This will compile your code and build the count program. The make command will compile the csapp.c file and include it in your program.

Testing

Use the grade tool to run the automated test suite:

# From the workspace directory
bin/grade .

# Or specify the workspace path
bin/grade ./workspaces/agent_count

The grade tool will compile your code and run all tests, showing which pass and fail. Focus on getting all tests to pass.

--- *COMP 321: Introduction to Computer Systems, Rice University, Spring 2024*

count.c4.5 KB

/*
 * COMP 321 Project 2: Word Count
 *
 * This program counts the number of characters, words, and lines in files.
 *
 * <Put your name and NetID here>
 */

#include <ctype.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

/* Structure to hold counts for a file */
struct counts {
    long chars;
    long words;
    long lines;
};

/* Function prototypes */
static int do_count(char *input_files[], const int nfiles,
    const bool char_flag, const bool word_flag,
    const bool line_flag, const bool test_flag);
static void print_counts(FILE *fp, struct counts *cnts,
    const char *name, const bool char_flag,
    const bool word_flag, const bool line_flag);
static void app_error_fmt(char *fmt, ...);

/*
 * Requires:
 *   "fp" is a valid output file stream.
 *   "cnts" is a valid pointer to a counts structure.
 *   "name" is a valid string.
 *
 * Effects:
 *   Prints the counts to fp in the format:
 *   [lines] [words] [chars] name
 *   Each count is omitted if the corresponding flag is false.
 */
static void
print_counts(FILE *fp, struct counts *cnts, const char *name,
    const bool char_flag, const bool word_flag, const bool line_flag)
{
    if (line_flag)
        fprintf(fp, "%8ld", cnts->lines);
    if (word_flag)
        fprintf(fp, "%8ld", cnts->words);
    if (char_flag)
        fprintf(fp, "%8ld", cnts->chars);
    fprintf(fp, " %s\n", name);
}

/*
 * Requires:
 *   "fmt" is a valid printf format string.
 *
 * Effects:
 *   Prints an error message to stderr in the format:
 *   ERROR: <formatted message>
 *   Does not terminate the program.
 */
__attribute__((unused))
static void
app_error_fmt(char *fmt, ...)
{
    va_list ap;
    fprintf(stderr, "ERROR: ");
    va_start(ap, fmt);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
    fprintf(stderr, "\n");
}

/*
 * Requires:
 *   "input_files" is a valid array of file name strings.
 *   "nfiles" is the number of files in the array.
 *
 * Effects:
 *   Counts characters, words, and/or lines in each file based on flags.
 *   Prints results for each file in ASCIIbetical order.
 *   Prints totals at the end.
 *   Returns 0 on success, 1-255 on error.
 */
static int
do_count(char *input_files[], const int nfiles,
    const bool char_flag, const bool word_flag,
    const bool line_flag, const bool test_flag)
{
    (void)test_flag; /* Suppress unused parameter warning */

    /*
     * TODO: Implement this function.
     *
     * 1. For each file in input_files (sorted ASCIIbetically):
     *    - Open and read the file
     *    - Count chars, words, and lines as requested by flags
     *    - Print the counts using print_counts()
     *    - Handle errors with app_error_fmt()
     *
     * 2. Print the total counts at the end
     */

    /* Placeholder - print zero counts for each file */
    int error_flag = 0;
    struct counts total = {0, 0, 0};

    for (int i = 0; i < nfiles; i++) {
        struct counts file_counts = {0, 0, 0};
        print_counts(stdout, &file_counts, input_files[i],
            char_flag, word_flag, line_flag);
    }

    /* Print totals (always print all three counts) */
    print_counts(stdout, &total, "total", true, true, true);

    return error_flag;
}

/*
 * Requires:
 *   Nothing.
 *
 * Effects:
 *   Parses command line arguments and calls do_count.
 *   Returns the value returned by do_count.
 */
int
main(int argc, char **argv)
{
    int c;
    bool char_flag = false;
    bool word_flag = false;
    bool line_flag = false;
    bool test_flag = false;

    /* Parse command line options */
    while ((c = getopt(argc, argv, "cltwh")) != -1) {
        switch (c) {
        case 'c':
            char_flag = true;
            break;
        case 'l':
            line_flag = true;
            break;
        case 't':
            test_flag = true;
            break;
        case 'w':
            word_flag = true;
            break;
        case 'h':
            printf("Usage: %s [-c] [-l] [-t] [-w] <files>\n", argv[0]);
            return 0;
        default:
            fprintf(stderr, "Usage: %s [-c] [-l] [-t] [-w] <files>\n",
                argv[0]);
            return 1;
        }
    }

    /* Check for at least one input file */
    if (optind >= argc) {
        fprintf(stderr, "Error: No input files specified\n");
        return 1;
    }

    /* Get the input files */
    int nfiles = argc - optind;
    char **input_files = &argv[optind];

    return do_count(input_files, nfiles, char_flag, word_flag,
        line_flag, test_flag);
}

count.c6.3 KB

/*
 * COMP 321 Project 2: Word Count
 *
 * This program counts the number of characters, words, and lines in files.
 *
 * <Put your name and NetID here>
 */

#include <ctype.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>


/* Structure to hold counts for a file */
struct counts {
    long chars;
    long words;
    long lines;
};

/* Structure to hold per-file data for sorting */
struct file_data {
    char *name;
    struct counts cnts;
    bool error;
};

/* Comparator for qsort: ASCIIbetical order by file name */
static int
compare_file_data(const void *a, const void *b)
{
    const struct file_data *fa = (const struct file_data *)a;
    const struct file_data *fb = (const struct file_data *)b;
    return strcmp(fa->name, fb->name);
}

/* Function prototypes */
static int do_count(char *input_files[], const int nfiles,
    const bool char_flag, const bool word_flag,
    const bool line_flag, const bool test_flag);
static void print_counts(FILE *fp, struct counts *cnts,
    const char *name, const bool char_flag,
    const bool word_flag, const bool line_flag);
static void app_error_fmt(char *fmt, ...);

/*
 * Requires:
 *   "fp" is a valid output file stream.
 *   "cnts" is a valid pointer to a counts structure.
 *   "name" is a valid string.
 *
 * Effects:
 *   Prints the counts to fp in the format:
 *   [lines] [words] [chars] name
 *   Each count is omitted if the corresponding flag is false.
 */
static void
print_counts(FILE *fp, struct counts *cnts, const char *name,
    const bool char_flag, const bool word_flag, const bool line_flag)
{
    if (line_flag)
        fprintf(fp, "%8ld", cnts->lines);
    if (word_flag)
        fprintf(fp, "%8ld", cnts->words);
    if (char_flag)
        fprintf(fp, "%8ld", cnts->chars);
    fprintf(fp, " %s\n", name);
}

/*
 * Requires:
 *   "fmt" is a valid printf format string.
 *
 * Effects:
 *   Prints an error message to stderr in the format:
 *   ERROR: <formatted message>
 *   Does not terminate the program.
 */
__attribute__((unused))
static void
app_error_fmt(char *fmt, ...)
{
    va_list ap;
    fprintf(stderr, "ERROR: ");
    va_start(ap, fmt);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
    fprintf(stderr, "\n");
}

/*
 * Requires:
 *   "input_files" is a valid array of file name strings.
 *   "nfiles" is the number of files in the array.
 *
 * Effects:
 *   Counts characters, words, and/or lines in each file based on flags.
 *   Prints results for each file in ASCIIbetical order.
 *   Prints totals at the end.
 *   Returns 0 on success, 1-255 on error.
 */
static int
do_count(char *input_files[], const int nfiles,
    const bool char_flag, const bool word_flag,
    const bool line_flag, const bool test_flag)
{
    (void)test_flag; /* Suppress unused parameter warning */

    int error_flag = 0;
    struct counts total = {0, 0, 0};

    /* Allocate per-file data array */
    struct file_data *files = malloc(nfiles * sizeof(struct file_data));
    if (files == NULL) {
        fprintf(stderr, "ERROR: out of memory\n");
        return 1;
    }

    /* Process each file in original order (for correct error message ordering) */
    for (int i = 0; i < nfiles; i++) {
        files[i].name = input_files[i];
        files[i].cnts.chars = 0;
        files[i].cnts.words = 0;
        files[i].cnts.lines = 0;
        files[i].error = false;

        FILE *fp = fopen(input_files[i], "r");
        if (fp == NULL) {
            app_error_fmt("cannot open file '%s'", input_files[i]);
            files[i].error = true;
            error_flag = 1;
            continue;
        }

        /* Single-pass count of chars, words, and lines */
        int c;
        bool in_word = false;

        while ((c = fgetc(fp)) != EOF) {
            files[i].cnts.chars++;
            if (c == '\n')
                files[i].cnts.lines++;
            if (isspace(c)) {
                in_word = false;
            } else {
                if (!in_word) {
                    files[i].cnts.words++;
                    in_word = true;
                }
            }
        }

        if (ferror(fp)) {
            app_error_fmt("cannot read file '%s'", input_files[i]);
            files[i].error = true;
            error_flag = 1;
        }

        fclose(fp);
    }

    /* Sort files in ASCIIbetical order by name */
    qsort(files, nfiles, sizeof(struct file_data), compare_file_data);

    /* Print results in sorted order, accumulating totals for flagged counts */
    for (int i = 0; i < nfiles; i++) {
        if (!files[i].error) {
            if (char_flag)
                total.chars += files[i].cnts.chars;
            if (word_flag)
                total.words += files[i].cnts.words;
            if (line_flag)
                total.lines += files[i].cnts.lines;
            print_counts(stdout, &files[i].cnts, files[i].name,
                char_flag, word_flag, line_flag);
        }
    }

    /* Print totals (always print all three counts) */
    print_counts(stdout, &total, "total", true, true, true);

    free(files);
    return error_flag;
}

/*
 * Requires:
 *   Nothing.
 *
 * Effects:
 *   Parses command line arguments and calls do_count.
 *   Returns the value returned by do_count.
 */
int
main(int argc, char **argv)
{
    int c;
    bool char_flag = false;
    bool word_flag = false;
    bool line_flag = false;
    bool test_flag = false;

    /* Parse command line options */
    while ((c = getopt(argc, argv, "cltwh")) != -1) {
        switch (c) {
        case 'c':
            char_flag = true;
            break;
        case 'l':
            line_flag = true;
            break;
        case 't':
            test_flag = true;
            break;
        case 'w':
            word_flag = true;
            break;
        case 'h':
            printf("Usage: %s [-c] [-l] [-t] [-w] <files>\n", argv[0]);
            return 0;
        default:
            fprintf(stderr, "Usage: %s [-c] [-l] [-t] [-w] <files>\n",
                argv[0]);
            return 1;
        }
    }

    /* Check for at least one input file */
    if (optind >= argc) {
        fprintf(stderr, "Error: No input files specified\n");
        return 1;
    }

    /* Get the input files */
    int nfiles = argc - optind;
    char **input_files = &argv[optind];

    return do_count(input_files, nfiles, char_flag, word_flag,
        line_flag, test_flag);
}

COMP 321 Project 2: Word Count

Student Information

Partner 1 name and NetID: Partner 2 name and NetID (if applicable):

Black Box Test Cases

1. No trailing newline: A file whose last line does not end with '\n' (e.g., hello world). Expected: chars=11, words=2, lines=0 (no '\n' means no lines counted). Verifies that the line counter only increments on '\n', not on EOF.

2. Multiple files in non-sorted order with -l flag: Run count -l zoo.txt apple.txt mango.txt where the files have known line counts. Expected: output lists apple.txt, mango.txt, zoo.txt in ASCIIbetical order, followed by a total line showing the sum of lines and zeros for words and chars.

3. Mix of existing and non-existing files: Run count -c -w -l real.txt fake.txt where real.txt exists and fake.txt does not. Expected: error on stderr for fake.txt, counts for real.txt on stdout in sorted order, and total reflecting only real.txt counts.

4. No flags specified: Run count file.txt with no counting flags. Expected: output line file.txt with no counts, followed by 0 0 0 total.

5. File with only whitespace (tabs and spaces, no newlines): Expected: chars=N (total whitespace chars), words=0 (all chars are whitespace), lines=0 (no '\n'). Verifies that words require non-whitespace characters and lines require '\n'.

White Box Test Cases and Edge Cases

1. Word boundary at start of file: A file beginning with whitespace before the first word (e.g., hello). Since in_word is initialized to false before the read loop, the first non-whitespace character after leading spaces correctly starts a new word. Expected: words=1.

2. Consecutive whitespace between words: A file with word1 word2 (multiple spaces). Each transition from non-space to space sets in_word=false; the first non-space after a space starts a new word. Expected: words=2, not more.

3. Upper-case before lower-case in sort: Run count -l Apple.txt apple.txt. Since 'A' (ASCII 65) < 'a' (ASCII 97), ASCIIbetical order puts Apple.txt before apple.txt. Verifies that strcmp-based sorting yields case-sensitive ordering.

4. Error message ordering with multiple bad files: Run count bad2.txt bad1.txt. Even though bad1.txt comes first alphabetically, the error messages appear on stderr in the order bad2.txt then bad1.txt (input order). Verifies that errors are reported in input_files order, not sorted order.

5. Large number of files: Run count on many files (e.g., 100) to verify that dynamic allocation via malloc works correctly and no memory is leaked or overwritten by qsort rearranging the file_data array.

Section: Black Box Test Cases

Score: 4/5 points

Assessment:

What was provided: Five specific, concrete test cases covering: no trailing newline, multiple files with sorting and -l flag, mix of existing/non-existing files with all flags, no flags specified, and whitespace-only file. Each test describes input and expected output clearly.

Strengths:

All five test cases are concrete with clearly described inputs and expected outputs
Good coverage of edge cases (no trailing newline, whitespace-only file)
Tests error handling with non-existent files (test 3)
Tests the "no flags" behavior which is a subtle specification point (test 4)
Tests ASCIIbetical ordering with multiple files (test 2)
Total line behavior is verified in tests 2 and 4

Errors/Gaps:

No testing of stdin/pipe input (the spec focuses on file arguments, but this is a standard input source category)
Limited flag combination coverage: only -l alone and -c -w -l together are tested; missing partial combinations like -cl, -cw, -lw
No empty file test case (0 chars, 0 words, 0 lines)
No test of -c or -w flags in isolation
No binary/special character file test

Detailed Feedback: The student provides well-crafted, specific test cases that demonstrate a solid understanding of the specification. The no-trailing-newline test (test 1) and whitespace-only file test (test 5) are particularly good edge cases. The error-handling test (test 3) nicely verifies that counts from failed files don't pollute the total. The no-flags test (test 4) catches a subtle specification requirement. However, the submission would benefit from more systematic coverage of flag combinations — testing -c alone, -w alone, and partial combinations like -lw would strengthen the suite. The absence of stdin testing and empty file testing costs some credit.

Rubric Breakdown:

Specific, concrete test cases with expected output: ✓ (all 5 are well-described)
Flag coverage: Partial — tests -l and -c -w -l but misses individual -c, -w, and partial combinations like -cl, -lw
Multiple files / input sources: ✓ (tests 2, 3) but no stdin
Edge cases: Good (no newline, whitespace-only) but missing empty file
Error handling: ✓ (test 3 with non-existent file)
Deduction: -1 for missing flag combination coverage and no stdin/empty file testing

---

Section: White Box Test Cases and Edge Cases

Score: 4/5 points

Assessment:

What was provided: Five test cases that reference internal implementation details: in_word state initialization, word-boundary state transitions, strcmp-based sorting, error message ordering (input order vs sorted order), and dynamic memory allocation with qsort.

Strengths:

Tests 1 and 2 are genuinely white-box — they explicitly reference the in_word boolean state variable and describe the state transition logic
Test 4 demonstrates understanding of a non-obvious implementation detail: errors printed in input_files array order while counts are printed in sorted order
Test 3 verifies strcmp-based ASCIIbetical sorting with a case-sensitive example
Test 5 shows awareness of dynamic allocation via malloc and qsort interactions
Clear distinction from the black-box tests — these tests are motivated by implementation knowledge

Errors/Gaps:

No buffer/read boundary testing (e.g., files larger than internal read buffer, files that are exact multiples of buffer size, very long lines crossing buffer boundaries)
No permission-denied error path test (different from non-existent file)
No read-error test (error during fread/fgetc mid-file)
Test 5 is somewhat vague — "large number of files" without specifying exact expected behavior or how to verify no memory leak
No test for file handle closure or resource management verification

Detailed Feedback: The student demonstrates genuine white-box testing awareness, particularly with the in_word state variable references in tests 1 and 2. These clearly show understanding of how the word-counting loop works internally. Test 4 is excellent — distinguishing between error output order (input array order) and count output order (sorted) is a subtle implementation detail that wouldn't be obvious from black-box testing alone. The main gap is the complete absence of buffer-handling tests, which is a significant white-box concern for any file-reading program. Testing how the program handles files at buffer boundaries, or files that cause read errors mid-stream, would round out this section. Test 5, while touching on important concerns (malloc, qsort), would be stronger with more specific expected behavior and verification criteria.

Rubric Breakdown:

Implementation-aware test cases: ✓ (tests 1, 2, 4 clearly reference internal state)
Code path coverage: Partial — covers word-boundary and sort paths, but not all error paths
Buffer/boundary testing: ✗ — no buffer-related tests
Error handling paths: Partial — test 4 covers error ordering but no permission-denied or read-error tests
Memory/resource management: Partial — test 5 mentions it but lacks specificity
Deduction: -1 for missing buffer boundary testing and incomplete error path coverage

---

Overall Summary

Section	Score	Notes
Black Box Test Cases	4/5	Strong concrete tests with good edge cases; missing flag combinations and stdin testing
White Box Test Cases and Edge Cases	4/5	Genuine white-box awareness with `in_word` state references; missing buffer boundary and error path tests
Total	8/10

General Comments:

This is a solid submission that demonstrates good understanding of both specification-based and implementation-based testing strategies. The student's strength is in providing concrete, specific test cases with clear expected outputs — particularly the in_word state transition tests and the error-ordering test, which show genuine insight into implementation details. The main areas for improvement are: (1) more systematic coverage of flag combinations in black-box testing, and (2) buffer/read boundary testing in white-box testing, which is a critical concern for any C file-processing program. Overall, the submission reflects a student who understands the program well but could be more thorough in covering all testing dimensions.

Total: 8/10

.mcp.json

diff --git a/.mcp.json b/.mcp.json
deleted file mode 100644
index 2ff7933..0000000
--- a/.mcp.json
+++ /dev/null
@@ -1,11 +0,0 @@
-{
-  "mcpServers": {
-    "bscs-bench": {
-      "command": "/Users/bebe/Code/bscs-bench/bin/bscs-mcp",
-      "args": [
-        "--workspace",
-        "/Users/bebe/Code/bscs-bench/workspaces/comp321_count_sonnet"
-      ]
-    }
-  }
-}
\ No newline at end of file

Agent Work: Word Count

COMP 321: Introduction to Computer Systems

Project 2: Word Count

Overview

Summary

Notes

Files

Building Your Program

Testing

COMP 321 Project 2: Word Count

Student Information

Black Box Test Cases

White Box Test Cases and Edge Cases

Section: Black Box Test Cases

Score: 4/5 points

Assessment:

Rubric Breakdown:

Section: White Box Test Cases and Edge Cases

Score: 4/5 points

Assessment:

Rubric Breakdown:

Overall Summary

General Comments:

Sub-Model Usage