M devices/file.c → devices/file.c

@@ -18,7 +18,7 @@ #include "../xyw.h"
 
 extern xyw_byte xyw_memory[];
 
-/* file device */
+// file device 
 #define FILE_PATH 0x0
 #define FILE_TYPE 0x2
 #define FILE_SIZE 0x3
@@ -28,33 +28,33 @@ #define FILE_READ 0x9
 #define FILE_WRITE 0xB
 #define FILE_OPERATION 0xD
 
-/* File operations */
+// File operations 
 #define FILE_OP_READ 0x01
 #define FILE_OP_WRITE 0x02
 #define FILE_OP_APPEND 0x03
 #define FILE_OP_DELETE 0x04
 
-/* File types */
+// File types 
 #define XYW_FILE_TYPE_UNKNOWN 0x00
 #define FILE_TYPE_FILE 0x01
 #define FILE_TYPE_DIRECTORY 0x02
 
-/* Error codes (high nibble = 3 for file device) */
+// Error codes (high nibble = 3 for file device) 
 #define FILE_ERROR_NOT_FOUND 0x31
 #define FILE_ERROR_ACCESS_DENIED 0x32
 #define FILE_ERROR_INVALID_OP 0x33
 #define FILE_ERROR_IO_ERROR 0x34
 
-/* Maximum path length */
+// Maximum path length 
 #define FILE_MAX_PATH 256
 
-/* Internal state for streaming */
+// Internal state for streaming 
 static FILE *file_handle = NULL;
 static char file_current_path[FILE_MAX_PATH] = {0};
 static long file_cursor = 0;
 static int file_is_write_mode = 0;
 
-/* Get null-terminated string from memory at given address */
+// Get null-terminated string from memory at given address 
 static void get_path_string(xyw_word addr, char *buf, size_t bufsize)
 {
     size_t i;
@@ -65,7 +65,7 @@ }
     buf[i] = '\0';
 }
 
-/* Close any open file */
+// Close any open file 
 static void file_close(void)
 {
     if (file_handle)
@@ -78,7 +78,7 @@ file_cursor = 0;
     file_is_write_mode = 0;
 }
 
-/* Update file type and size based on path */
+// Update file type and size based on path 
 static void update_file_stats(xyw_byte *data)
 {
     xyw_word path_addr = XYW_PEEKW(&data[FILE_PATH]);
@@ -109,7 +109,7 @@ }
     else if (S_ISREG(st.st_mode))
     {
         data[FILE_TYPE] = FILE_TYPE_FILE;
-        /* Cap size at 64KB (0xFFFF) */
+        // Cap size at 64KB (0xFFFF) 
         xyw_word size = (st.st_size > 0xFFFF) ? 0xFFFF : (xyw_word)st.st_size;
         XYW_POKEW(&data[FILE_SIZE], size);
     }
@@ -120,7 +120,7 @@ XYW_POKEW(&data[FILE_SIZE], 0);
     }
 }
 
-/* Read file contents into memory buffer with cursor support */
+// Read file contents into memory buffer with cursor support 
 static void file_read(xyw_byte *data, xyw_byte *error)
 {
     xyw_word path_addr = XYW_PEEKW(&data[FILE_PATH]);
@@ -128,7 +128,7 @@ xyw_word buffer_addr = XYW_PEEKW(&data[FILE_READ]);
     xyw_word length = XYW_PEEKW(&data[FILE_LENGTH]);
     char path[FILE_MAX_PATH];
 
-    /* Clear success */
+    // Clear success 
     XYW_POKEW(&data[FILE_SUCCESS], 0);
 
     if (path_addr == 0 || buffer_addr == 0 || length == 0)
@@ -142,7 +142,7 @@ get_path_string(path_addr, path, FILE_MAX_PATH);
 
     XYW_DBG("   Reading file: %s, length=%u, cursor=%ld\n", path, length, file_cursor);
 
-    /* Check if it's a directory - list contents (no cursor support for dirs) */
+    // Check if it's a directory - list contents (no cursor support for dirs) 
     if (data[FILE_TYPE] == FILE_TYPE_DIRECTORY)
     {
         xyw_word offset = 0;
@@ -162,7 +162,7 @@ *error = FILE_ERROR_ACCESS_DENIED;
             return;
         }
 
-        /* Output . and .. first */
+        // Output . and .. first 
         char line[FILE_MAX_PATH + 16];
         int len = snprintf(line, sizeof(line), "%02X %04X .\n", FILE_TYPE_DIRECTORY, 0);
         if (len <= (int)length)
@@ -217,7 +217,7 @@ *error = FILE_ERROR_ACCESS_DENIED;
             return;
         }
 
-        /* Output . and .. first */
+        // Output . and .. first
         char line[FILE_MAX_PATH + 16];
         int len = snprintf(line, sizeof(line), "%02X %04X .\n", FILE_TYPE_DIRECTORY, 0);
         if (len <= (int)length)
@@ -270,7 +270,7 @@ 
         closedir(dir);
 #endif
 
-        /* Null-terminate if space */
+        // Null-terminate if space 
         if (offset < length)
         {
             xyw_memory[buffer_addr + offset] = 0;
@@ -280,9 +280,9 @@ XYW_POKEW(&data[FILE_SUCCESS], offset);
         return;
     }
 
-    /* Regular file read with cursor */
+    // Regular file read with cursor 
 
-    /* Open file if not already open or if path changed */
+    // Open file if not already open or if path changed 
     if (!file_handle || strcmp(file_current_path, path) != 0 || file_is_write_mode)
     {
         file_close();
@@ -299,21 +299,21 @@ file_cursor = 0;
         file_is_write_mode = 0;
     }
 
-    /* Seek to cursor position */
-    if (fseek(file_handle, file_cursor, SEEK_SET) != 0)
+    // Seek to cursor position, only if not already there 
+    if (ftell(file_handle) != file_cursor && fseek(file_handle, file_cursor, SEEK_SET) != 0)
     {
         XYW_DBG("   Failed to seek in file: %s\n", path);
         *error = FILE_ERROR_IO_ERROR;
         return;
     }
 
-    /* Read data */
+    // Read data 
     size_t bytes_read = fread(&xyw_memory[buffer_addr], 1, length, file_handle);
 
-    /* Advance cursor */
+    // Advance cursor 
     file_cursor += bytes_read;
 
-    /* Null-terminate if space and we read less than length */
+    // Null-terminate if space and we read less than length 
     if (bytes_read < length)
     {
         xyw_memory[buffer_addr + bytes_read] = 0;
@@ -323,7 +323,7 @@ XYW_DBG("   Read %zu bytes, cursor now at %ld\n", bytes_read, file_cursor);
     XYW_POKEW(&data[FILE_SUCCESS], (xyw_word)bytes_read);
 }
 
-/* Write memory buffer to file with cursor support */
+// Write memory buffer to file with cursor support 
 static void file_write_op(xyw_byte *data, xyw_byte *error, int append)
 {
     xyw_word path_addr = XYW_PEEKW(&data[FILE_PATH]);
@@ -331,7 +331,7 @@ xyw_word buffer_addr = XYW_PEEKW(&data[FILE_WRITE]);
     xyw_word length = XYW_PEEKW(&data[FILE_LENGTH]);
     char path[FILE_MAX_PATH];
 
-    /* Clear success */
+    // Clear success 
     XYW_POKEW(&data[FILE_SUCCESS], 0);
 
     if (path_addr == 0 || buffer_addr == 0 || length == 0)
@@ -345,7 +345,7 @@ get_path_string(path_addr, path, FILE_MAX_PATH);
 
     XYW_DBG("   Writing to file: %s (append=%d), length=%u, cursor=%ld\n", path, append, length, file_cursor);
 
-    /* Open file if not already open, path changed, or mode changed */
+    // Open file if not already open, path changed, or mode changed 
     int need_reopen = !file_handle ||
                       strcmp(file_current_path, path) != 0 ||
                       !file_is_write_mode;
@@ -354,14 +354,14 @@ if (need_reopen)
     {
         file_close();
 
-        /* For append, open in append mode; otherwise open for read/write or create */
+        // For append, open in append mode; otherwise open for read/write or create 
         if (append)
         {
             file_handle = fopen(path, "ab");
         }
         else
         {
-            /* Try to open existing file for r+b, if fails create with wb */
+            // Try to open existing file for r+b, if fails create with wb 
             file_handle = fopen(path, "r+b");
             if (!file_handle)
             {
@@ -382,7 +382,7 @@ file_is_write_mode = 1;
 
         if (append)
         {
-            /* Seek to end for append */
+            // Seek to end for append 
             fseek(file_handle, 0, SEEK_END);
             file_cursor = ftell(file_handle);
         }
@@ -392,15 +392,15 @@ file_cursor = 0;
         }
     }
 
-    /* Seek to cursor position (for non-append continuing writes) */
-    if (!append && fseek(file_handle, file_cursor, SEEK_SET) != 0)
+    // Seek to cursor position (for non-append continuing writes), skip if already positioned 
+    if (!append && ftell(file_handle) != file_cursor && fseek(file_handle, file_cursor, SEEK_SET) != 0)
     {
         XYW_DBG("   Failed to seek in file: %s\n", path);
         *error = FILE_ERROR_IO_ERROR;
         return;
     }
 
-    /* Find actual content length (stop at null terminator if present) */
+    // Find actual content length (stop at null terminator if present) 
     xyw_word actual_length = 0;
     while (actual_length < length && xyw_memory[buffer_addr + actual_length] != 0)
     {
@@ -413,27 +413,26 @@ XYW_DBG("   Empty content for file_write\n");
         return;
     }
 
-    /* Write data */
+    // Write data
     size_t written = fwrite(&xyw_memory[buffer_addr], 1, actual_length, file_handle);
-    fflush(file_handle);
 
-    /* Advance cursor */
+    // Advance cursor
     file_cursor += written;
 
     XYW_DBG("   Wrote %zu bytes (of %u max), cursor now at %ld\n", written, length, file_cursor);
     XYW_POKEW(&data[FILE_SUCCESS], (xyw_word)written);
 
-    /* Update stats after write */
-    update_file_stats(data);
+    // Update file size
+    data[FILE_TYPE] = FILE_TYPE_FILE;
+    XYW_POKEW(&data[FILE_SIZE], (xyw_word)(file_cursor > 0xFFFF ? 0xFFFF : file_cursor));
 }
 
-/* Delete a file */
+// Delete a file 
 static void file_delete(xyw_byte *data, xyw_byte *error)
 {
     xyw_word path_addr = XYW_PEEKW(&data[FILE_PATH]);
     char path[FILE_MAX_PATH];
 
-    /* Clear success */
     XYW_POKEW(&data[FILE_SUCCESS], 0);
 
     if (path_addr == 0)
@@ -445,7 +444,7 @@ }
 
     get_path_string(path_addr, path, FILE_MAX_PATH);
 
-    /* Close file if it's the one being deleted */
+    // Close file if it's the one being deleted
     if (file_handle && strcmp(file_current_path, path) == 0)
     {
         file_close();
@@ -460,19 +459,19 @@ *error = FILE_ERROR_ACCESS_DENIED;
         return;
     }
 
-    /* Success = 1 for successful delete */
+    // Success = 1 for successful delete 
     XYW_POKEW(&data[FILE_SUCCESS], 1);
 
-    /* Update stats after delete */
+    // Update stats after delete 
     update_file_stats(data);
 }
 
 void file_setup(xyw_byte *data)
 {
-    /* Close any open file */
+    // Close any open file 
     file_close();
 
-    /* Clear all device memory */
+    // Clear all device memory 
     memset(data, 0, 16);
 }
 
@@ -492,7 +491,7 @@ file_close();
         update_file_stats(data);
     }
 
-    /* When operation is written, execute it */
+    // When operation is written, execute it 
     if (addr == FILE_OPERATION)
     {
         xyw_byte op = data[FILE_OPERATION];
@@ -519,7 +518,7 @@ }
             break;
         }
 
-        /* Clear operation after execution */
+        // Clear operation after execution 
         data[FILE_OPERATION] = 0;
     }
 }