Version v0.2.20 - Add comprehensive help flag support and fix pad selection to prioritize hex prefix matching over number selection

README.md

@@ -164,11 +164,9 @@ Offset | Size | Field               | Description
 4      | 2    | Version           | Format version (currently 1)
 6      | 32   | Pad Checksum      | Binary pad checksum (32 bytes)
 38     | 8    | Pad Offset        | Offset in pad file (uint64_t)
-46     | 2    | Filename Length   | Original filename length (uint16_t)
+46     | 4    | File Mode         | Original file permissions (uint32_t)
-48     | var  | Original Filename | Original filename string
+50     | 8    | File Size         | Original file size (uint64_t)
-var    | 4    | File Mode         | Original file permissions (uint32_t)
+58     | var  | Encrypted Data    | XOR-encrypted file contents
-var    | 8    | File Size         | Original file size (uint64_t)
-var    | var  | Encrypted Data    | XOR-encrypted file contents
 ```
 
 ### .otp.asc File Format (ASCII Armored)
@@ -185,7 +183,7 @@ Pad-Offset: <decimal-offset-value>
 -----END OTP MESSAGE-----
 ```
 
-**Note:** ASCII armored files lose original filename and permission metadata.
+**Note:** ASCII armored files do not preserve original file permissions metadata.
 
 ## Usage Examples
 

otp.c

@@ -151,6 +151,14 @@ int interactive_mode(void) {
 }
 
 int command_line_mode(int argc, char* argv[]) {
+    // Check for help flags first
+    if (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--h") == 0 || 
+        strcmp(argv[1], "-help") == 0 || strcmp(argv[1], "--help") == 0 || 
+        strcmp(argv[1], "help") == 0) {
+        print_usage(argv[0]);
+        return 0;
+    }
+    
     if (strcmp(argv[1], "generate") == 0 || strcmp(argv[1], "-g") == 0) {
         if (argc != 3) {
             printf("Usage: %s generate|-g <size>\n", argv[0]);
@@ -374,31 +382,7 @@ char* find_pad_by_prefix(const char* prefix) {
     char* matches[100];  // Store up to 100 matches
     int match_count = 0;
     
-    // Check if it's a number (for interactive menu selection)
+    // Always try hex prefix matching first
-    // Only treat as number if it's a single digit (1-9) to avoid conflicts with hex prefixes
-    char* endptr;
-    int selection = strtol(prefix, &endptr, 10);
-    if (*endptr == '\0' && selection > 0 && selection <= 9 && strlen(prefix) == 1) {
-        // It's a number, find the nth pad
-        int current = 0;
-        rewinddir(dir);
-        while ((entry = readdir(dir)) != NULL && match_count == 0) {
-            // Skip . and .. entries, and only process .pad files
-            if (entry->d_name[0] == '.') continue;
-            if (!strstr(entry->d_name, ".pad")) continue;
-            if (strlen(entry->d_name) != 68) continue; // 64 char chksum + ".pad"
-            
-            current++;
-            if (current == selection) {
-                matches[match_count] = malloc(65);
-                strncpy(matches[match_count], entry->d_name, 64);
-                matches[match_count][64] = '\0';
-                match_count = 1;
-                break;
-            }
-        }
-    } else {
-        // Find pads that start with the prefix
     size_t prefix_len = strlen(prefix);
     while ((entry = readdir(dir)) != NULL && match_count < 100) {
         // Skip . and .. entries, and only process .pad files
@@ -414,6 +398,31 @@ char* find_pad_by_prefix(const char* prefix) {
             match_count++;
         }
     }
+    
+    // If no hex prefix matches and it looks like a small number, try number selection
+    if (match_count == 0) {
+        char* endptr;
+        int selection = strtol(prefix, &endptr, 10);
+        if (*endptr == '\0' && selection > 0 && selection <= 100) {
+            // It's a number, find the nth pad
+            int current = 0;
+            rewinddir(dir);
+            while ((entry = readdir(dir)) != NULL) {
+                // Skip . and .. entries, and only process .pad files
+                if (entry->d_name[0] == '.') continue;
+                if (!strstr(entry->d_name, ".pad")) continue;
+                if (strlen(entry->d_name) != 68) continue; // 64 char chksum + ".pad"
+                
+                current++;
+                if (current == selection) {
+                    matches[match_count] = malloc(65);
+                    strncpy(matches[match_count], entry->d_name, 64);
+                    matches[match_count][64] = '\0';
+                    match_count = 1;
+                    break;
+                }
+            }
+        }
     }
     
     closedir(dir);
@@ -1445,16 +1454,6 @@ int encrypt_file(const char* pad_identifier, const char* input_file, const char*
         // Pad offset: 8 bytes
         fwrite(&current_offset, sizeof(uint64_t), 1, output_fp);
         
-        // Original filename length and name
-        const char* base_filename = strrchr(input_file, '/');
-        if (base_filename) {
-            base_filename++; // Skip the '/'
-        } else {
-            base_filename = input_file;
-        }
-        uint16_t filename_len = strlen(base_filename);
-        fwrite(&filename_len, sizeof(uint16_t), 1, output_fp);
-        fwrite(base_filename, 1, filename_len, output_fp);
         
         // File mode: 4 bytes
         uint32_t file_mode = input_stat.st_mode;
@@ -1527,7 +1526,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     uint16_t version;
     unsigned char pad_chksum_bin[32];
     uint64_t pad_offset;
-    uint16_t filename_len;
     uint32_t file_mode;
     uint64_t file_size;
     
@@ -1535,7 +1533,8 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
         fread(&version, sizeof(uint16_t), 1, input_fp) != 1 ||
         fread(pad_chksum_bin, 1, 32, input_fp) != 32 ||
         fread(&pad_offset, sizeof(uint64_t), 1, input_fp) != 1 ||
-        fread(&filename_len, sizeof(uint16_t), 1, input_fp) != 1) {
+        fread(&file_mode, sizeof(uint32_t), 1, input_fp) != 1 ||
+        fread(&file_size, sizeof(uint64_t), 1, input_fp) != 1) {
         printf("Error: Cannot read binary header\n");
         fclose(input_fp);
         return 1;
@@ -1547,25 +1546,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
         return 1;
     }
     
-    // Read original filename
-    char* original_filename = malloc(filename_len + 1);
-    if (fread(original_filename, 1, filename_len, input_fp) != filename_len) {
-        printf("Error: Cannot read original filename\n");
-        free(original_filename);
-        fclose(input_fp);
-        return 1;
-    }
-    original_filename[filename_len] = '\0';
-    
-    // Read remaining header
-    if (fread(&file_mode, sizeof(uint32_t), 1, input_fp) != 1 ||
-        fread(&file_size, sizeof(uint64_t), 1, input_fp) != 1) {
-        printf("Error: Cannot read file metadata\n");
-        free(original_filename);
-        fclose(input_fp);
-        return 1;
-    }
-    
     // Convert binary checksum to hex
     char pad_chksum_hex[65];
     for (int i = 0; i < 32; i++) {
@@ -1574,7 +1554,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     pad_chksum_hex[64] = '\0';
     
     printf("Decrypting binary file...\n");
-    printf("Original filename: %s\n", original_filename);
     printf("File size: %lu bytes\n", file_size);
     
     // Check if we have the required pad
@@ -1586,7 +1565,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
         printf("Error: Required pad not found: %s\n", pad_chksum_hex);
         printf("Available pads:\n");
         list_available_pads();
-        free(original_filename);
         fclose(input_fp);
         return 1;
     }
@@ -1594,8 +1572,7 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     // Determine output filename
     char default_output[512];
     if (output_file == NULL) {
-        strncpy(default_output, original_filename, sizeof(default_output) - 1);
+        snprintf(default_output, sizeof(default_output), "decrypted.bin");
-        default_output[sizeof(default_output) - 1] = '\0';
         output_file = default_output;
     }
     
@@ -1603,7 +1580,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     unsigned char* encrypted_data = malloc(file_size);
     if (fread(encrypted_data, 1, file_size, input_fp) != file_size) {
         printf("Error: Cannot read encrypted data\n");
-        free(original_filename);
         free(encrypted_data);
         fclose(input_fp);
         return 1;
@@ -1614,14 +1590,12 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     FILE* pad_file = fopen(pad_path, "rb");
     if (!pad_file) {
         printf("Error: Cannot open pad file\n");
-        free(original_filename);
         free(encrypted_data);
         return 1;
     }
     
     if (fseek(pad_file, pad_offset, SEEK_SET) != 0) {
         printf("Error: Cannot seek to offset in pad file\n");
-        free(original_filename);
         free(encrypted_data);
         fclose(pad_file);
         return 1;
@@ -1630,7 +1604,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     unsigned char* pad_data = malloc(file_size);
     if (fread(pad_data, 1, file_size, pad_file) != file_size) {
         printf("Error: Cannot read pad data\n");
-        free(original_filename);
         free(encrypted_data);
         free(pad_data);
         fclose(pad_file);
@@ -1647,7 +1620,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     FILE* output_fp = fopen(output_file, "wb");
     if (!output_fp) {
         printf("Error: Cannot create output file %s\n", output_file);
-        free(original_filename);
         free(encrypted_data);
         free(pad_data);
         return 1;
@@ -1655,7 +1627,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     
     if (fwrite(encrypted_data, 1, file_size, output_fp) != file_size) {
         printf("Error: Cannot write decrypted data\n");
-        free(original_filename);
         free(encrypted_data);
         free(pad_data);
         fclose(output_fp);
@@ -1672,7 +1643,6 @@ int decrypt_binary_file(FILE* input_fp, const char* output_file) {
     printf("Restored permissions and metadata\n");
     
     // Cleanup
-    free(original_filename);
     free(encrypted_data);
     free(pad_data);