docs(cnadd): add Doxygen comments to functions

Added detailed Doxygen-style documentation comments to ensure_directory_exists,
get_cnotes_path, write_entry, print_usage, and main functions in src/cnadd.c.
Also included a backup of the original file as src/cnadd.c.bak and fixed
missing newline at end of file.

src/cnadd.c

@@ -7,6 +7,11 @@
 #include "platform.h"
 #include "config.h"
 
+/**
+ * @brief Ensures that the directory at the given path exists, creating it if necessary.
+ * @param path The path to the directory.
+ * @return 1 if the directory exists or was created successfully, 0 otherwise.
+ */
 int ensure_directory_exists(const char *path) {
     struct stat st;
     
@@ -37,6 +42,12 @@ int ensure_directory_exists(const char *path) {
     return 1;
 }
 
+/**
+ * @brief Retrieves the path to the cnotes directory, using environment variables if set.
+ * @param buffer Buffer to store the path.
+ * @param bufsize Size of the buffer.
+ * @return 1 if the path was successfully retrieved, 0 otherwise.
+ */
 int get_cnotes_path(char *buffer, size_t bufsize) {
     const char *custom_path;
     const char *home;
@@ -81,6 +92,12 @@ int get_cnotes_path(char *buffer, size_t bufsize) {
     return 1;
 }
 
+/**
+ * @brief Writes a new entry to the cnotes file with the given category and message.
+ * @param category The category for the entry (max 10 characters).
+ * @param message The message text (max 80 characters).
+ * @return 1 if the entry was written successfully, 0 otherwise.
+ */
 int write_entry(const char *category, const char *message) {
     char dir_path[512];
     char file_path[600];
@@ -154,6 +171,10 @@ int write_entry(const char *category, const char *message) {
     return 1;
 }
 
+/**
+ * @brief Prints the usage information for the program.
+ * @param prog_name The name of the program.
+ */
 void print_usage(const char *prog_name) {
     fprintf(stderr, "Usage: %s [-c category] message\n", prog_name);
     fprintf(stderr, "  -c category  Optional category (max 10 chars, default: %s)\n", 
@@ -161,6 +182,12 @@ void print_usage(const char *prog_name) {
     fprintf(stderr, "  message      Required message text (max 80 chars). Wrapped in double-quotes.\n");
 }
 
+/**
+ * @brief Main entry point of the program.
+ * @param argc Number of command-line arguments.
+ * @param argv Array of command-line arguments.
+ * @return 0 on success, 1 on failure.
+ */
 int main(int argc, char *argv[]) {
     const char *category;
     const char *message;
@@ -200,4 +227,4 @@ int main(int argc, char *argv[]) {
     }
     
     return 0;
-}
+}

src/cnadd.c.bak

@@ -0,0 +1,194 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <sys/stat.h>
+
+#include "platform.h"
+#include "config.h"
+
+int ensure_directory_exists(const char *path) {
+    struct stat st;
+    
+    if (stat(path, &st) == 0) {
+        /* Path exists, check if it's a directory */
+        if (S_ISDIR(st.st_mode)) {
+            return 1;
+        } else {
+            fprintf(stderr, "Error: %s exists but is not a directory\n", path);
+            return 0;
+        }
+    }
+    
+    /* Directory doesn't exist, try to create it */
+    if (mkdir_portable(path) != 0) {
+        fprintf(stderr, "Error: Cannot create directory %s\n", path);
+        return 0;
+    }
+    return 1;
+}
+
+int get_cnotes_path(char *buffer, size_t bufsize) {
+    const char *custom_path;
+    const char *home;
+    size_t len;
+
+    /* First check for CNOTES_PATH environment variable override */
+    custom_path = getenv(CNOTES_PATH_ENV);
+    if (custom_path != NULL && strlen(custom_path) > 0) {
+        if (strlen(custom_path) >= bufsize) {
+            fprintf(stderr, "Error: Path too long\n");
+            return 0;
+        }
+        strcpy(buffer, custom_path);
+        return 1;
+    }
+
+    /* Fall back to HOME_ENV + CNOTES_DIR */
+    home = getenv(HOME_ENV);
+    if (home == NULL) {
+        fprintf(stderr, "Error: %s environment variable not set\n", HOME_ENV);
+        fprintf(stderr, "Hint: Set %s to specify notes directory\n", CNOTES_PATH_ENV);
+        return 0;
+    }
+
+    /* Build path: $HOME/CNOTES_DIR (or just $HOME if CNOTES_DIR is empty) */
+    len = strlen(home);
+    if (strlen(CNOTES_DIR) == 0) {
+        /* DOS mode: use home directory directly */
+        if (len >= bufsize) {
+            fprintf(stderr, "Error: Path too long\n");
+            return 0;
+        }
+        strcpy(buffer, home);
+    } else {
+        /* Unix/Windows: append CNOTES_DIR to home */
+        if (len + strlen(CNOTES_DIR) + 2 > bufsize) {
+            fprintf(stderr, "Error: Path too long\n");
+            return 0;
+        }
+        sprintf(buffer, "%s" PATH_SEP_STR "%s", home, CNOTES_DIR);
+    }
+    return 1;
+}
+
+int write_entry(const char *category, const char *message) {
+    char dir_path[512];
+    char file_path[600];
+    FILE *file;
+    time_t now;
+    struct tm *tm_info;
+    char date[11];
+    char time_str[6];
+    char padded_category[CATEGORY_LENGTH + 1];
+    char truncated_message[FREETEXT_MAX_LENGTH + 1];
+    int i;
+    
+    /* Get current date and time */
+    now = time(NULL);
+    if (now == -1) {
+        fprintf(stderr, "Error: Cannot get current time\n");
+        return 0;
+    }
+    
+    tm_info = localtime(&now);
+    if (tm_info == NULL) {
+        fprintf(stderr, "Error: Cannot convert time\n");
+        return 0;
+    }
+    
+    /* Format date as YYYY-MM-DD */
+    strftime(date, sizeof(date), "%Y-%m-%d", tm_info);
+    
+    /* Format time as HH:MM */
+    strftime(time_str, sizeof(time_str), "%H:%M", tm_info);
+    
+    /* Pad category to 10 characters */
+    strncpy(padded_category, category, CATEGORY_LENGTH);
+    padded_category[CATEGORY_LENGTH] = '\0';
+    for (i = (int)strlen(padded_category); i < CATEGORY_LENGTH; i++) {
+        padded_category[i] = ' ';
+    }
+    padded_category[CATEGORY_LENGTH] = '\0';
+    
+    /* Truncate message to 80 characters */
+    strncpy(truncated_message, message, FREETEXT_MAX_LENGTH);
+    truncated_message[FREETEXT_MAX_LENGTH] = '\0';
+    
+    /* Get cnotes directory path */
+    if (!get_cnotes_path(dir_path, sizeof(dir_path))) {
+        return 0;
+    }
+    
+    /* Ensure directory exists */
+    if (!ensure_directory_exists(dir_path)) {
+        return 0;
+    }
+    
+    /* Build full file path */
+    sprintf(file_path, "%s" PATH_SEP_STR "%s", dir_path, CNOTES_FILE);
+    
+    /* Open file in append mode */
+    file = fopen(file_path, "a");
+    if (file == NULL) {
+        fprintf(stderr, "Error: Cannot open file %s\n", file_path);
+        return 0;
+    }
+    
+    /* Write entry */
+    fprintf(file, "%s,%s,%s,\"%s\"\n", 
+            date, time_str, padded_category, truncated_message);
+    
+    fclose(file);
+    
+    printf("Entry added to %s\n", file_path);
+    return 1;
+}
+
+void print_usage(const char *prog_name) {
+    fprintf(stderr, "Usage: %s [-c category] message\n", prog_name);
+    fprintf(stderr, "  -c category  Optional category (max 10 chars, default: %s)\n", 
+            DEFAULT_CATEGORY);
+    fprintf(stderr, "  message      Required message text (max 80 chars). Wrapped in double-quotes.\n");
+}
+
+int main(int argc, char *argv[]) {
+    const char *category;
+    const char *message;
+    int i;
+    
+    category = DEFAULT_CATEGORY;
+    message = NULL;
+    
+    /* Parse command-line arguments */
+    i = 1;
+    while (i < argc) {
+        if (strcmp(argv[i], "-c") == 0) {
+            if (i + 1 >= argc) {
+                fprintf(stderr, "Error: -c option requires an argument\n");
+                print_usage(argv[0]);
+                return 1;
+            }
+            category = argv[i + 1];
+            i += 2;
+        } else {
+            message = argv[i];
+            i++;
+            break;  /* Only take first non-option as message */
+        }
+    }
+    
+    /* Validate arguments */
+    if (message == NULL || strlen(message) == 0) {
+        fprintf(stderr, "Error: Message is required\n");
+        print_usage(argv[0]);
+        return 1;
+    }
+    
+    /* Write entry */
+    if (!write_entry(category, message)) {
+        return 1;
+    }
+    
+    return 0;
+}