Merge pull request #9 from speedy-lex/main

emulator drive

src/components/drive.c

@@ -51,6 +51,11 @@ void nn_drive_readSector(nn_drive *drive, void *_, nn_component *component, nn_c
     nn_value sectorValue = nn_getArgument(computer, 0);
     int sector = nn_toInt(sectorValue);
     size_t sector_size = drive->getSectorSize(component, drive->userdata);
+    // we leave the +1 intentionally to compare the end of the real sector
+    if (sector < 1 || (sector * sector_size > drive->getCapacity(component, drive->userdata))) {
+        nn_setCError(computer, "bad argument #1 (sector out of range)");
+        return;
+    }
     char buf[sector_size];
     drive->readSector(component, drive->userdata, sector, buf);
     nn_return_string(computer, buf, sector_size);
@@ -60,16 +65,31 @@ void nn_drive_writeSector(nn_drive *drive, void *_, nn_component *component, nn_
     int sector = nn_toInt(sectorValue);
     size_t sector_size = drive->getSectorSize(component, drive->userdata);
     nn_value bufValue = nn_getArgument(computer, 1);
-    const char *buf = nn_toString(bufValue, &sector_size);
+
+    size_t buf_size = 0;
+    const char *buf = nn_toString(bufValue, &buf_size);
+    if (buf_size != sector_size) {
+        nn_setCError(computer, "bad argument #2 (expected buffer of length `sectorSize`)");
+        return;
+    }
+    // we leave the +1 intentionally to compare the end of the real sector
+    if (sector < 1 || (sector * sector_size > drive->getCapacity(component, drive->userdata))) {
+        nn_setCError(computer, "bad argument #1 (sector out of range)");
+        return;
+    }
     drive->writeSector(component, drive->userdata, sector, buf);
 }
 void nn_drive_readByte(nn_drive *drive, void *_, nn_component *component, nn_computer *computer) {
     nn_value offsetValue = nn_getArgument(computer, 0);
-    size_t disk_offset = nn_toInt(offsetValue);
+    size_t disk_offset = nn_toInt(offsetValue) - 1;
     size_t sector_size = drive->getSectorSize(component, drive->userdata);
-    int sector = disk_offset / sector_size;
+    int sector = (disk_offset / sector_size) + 1;
     size_t sector_offset = disk_offset % sector_size;
 
+    if (disk_offset >= drive->getCapacity(component, drive->userdata)) {
+        nn_setCError(computer, "bad argument #1 (index out of range)");
+        return;
+    }
     char buf[sector_size];
     drive->readSector(component, drive->userdata, sector, buf);
 
@@ -78,12 +98,20 @@ void nn_drive_readByte(nn_drive *drive, void *_, nn_component *component, nn_com
 void nn_drive_writeByte(nn_drive *drive, void *_, nn_component *component, nn_computer *computer) {
     nn_value offsetValue = nn_getArgument(computer, 0);
     nn_value writeValue = nn_getArgument(computer, 1);
-    size_t disk_offset = nn_toInt(offsetValue);
+    size_t disk_offset = nn_toInt(offsetValue) - 1;
-    char write = nn_toInt(writeValue);
+    intptr_t write = nn_toInt(writeValue);
     size_t sector_size = drive->getSectorSize(component, drive->userdata);
-    int sector = disk_offset / sector_size;
+    int sector = (disk_offset / sector_size) + 1;
     size_t sector_offset = disk_offset % sector_size;
 
+    if (write < -128 || write > 255) {
+        nn_setCError(computer, "bad argument #2 (byte out of range)");
+        return;
+    }
+    if (disk_offset >= drive->getCapacity(component, drive->userdata)) {
+        nn_setCError(computer, "bad argument #1 (index out of range)");
+        return;
+    }
     char buf[sector_size];
     drive->readSector(component, drive->userdata, sector, buf);
 

src/emulator.c

@@ -238,6 +238,47 @@ bool ne_fs_exists(nn_component *component, ne_fs *fs, const char *path) {
     return FileExists(p) || DirectoryExists(p);
 }
 
+typedef struct ne_drive {
+    FILE *file;
+} ne_drive;
+
+void ne_drive_close(nn_component *component, ne_drive *drive) {
+    fclose(drive->file);
+}
+nn_driveControl ne_drive_getControl(nn_component *component, ne_drive *_) {
+    return (nn_driveControl){};
+}
+size_t ne_drive_getPlatterCount(nn_component *component, ne_drive *_) {
+    return 1;
+}
+size_t ne_drive_getSectorSize(nn_component *component, ne_drive *_) {
+    return 512;
+}
+size_t ne_drive_getCapacity(nn_component *component, ne_drive *drive) {
+    fseek(drive->file, 0, SEEK_END);
+    return ftell(drive->file);
+}
+void ne_drive_readSector(nn_component *component, ne_drive *drive, int shifted_sector, char *buf) {
+    int sector = shifted_sector - 1;
+    size_t sectorSize = ne_drive_getSectorSize(component, drive);
+
+    size_t offset = sector * sectorSize;
+    fseek(drive->file, offset, SEEK_SET);
+    fread(buf, sizeof(char), sectorSize, drive->file);
+}
+void ne_drive_writeSector(nn_component *component, ne_drive *drive, int shifted_sector, const char *buf) {
+    int sector = shifted_sector - 1;
+    size_t sectorSize = ne_drive_getSectorSize(component, drive);
+
+    size_t offset = sector * sectorSize;
+    fseek(drive->file, offset, SEEK_SET);
+    fwrite(buf, sizeof(char), sectorSize, drive->file);
+
+    // this is probably not needed but i believe someone isn't running the deinit
+    fflush(drive->file);
+}
+
+
 int keycode_to_oc(int keycode) {
     switch (keycode) {
         case KEY_NULL:
@@ -533,6 +574,27 @@ int main() {
     };
     nn_addFileSystem(computer, "OpenOS", 1, &genericFS);
 
+    ne_drive drive = {
+        .file = fopen("data/drive.img", "r+")
+    };
+    assert(drive.file != NULL);
+
+    nn_drive genericDrive = {
+        .refc = 0,
+        .userdata = &drive,
+        .deinit = (void *)ne_drive_close,
+        .control = (void *)ne_drive_getControl,
+        .getLabel = ne_eeprom_getLabel,
+        .setLabel = ne_eeprom_setLabel,
+        .getPlatterCount = (void *)ne_drive_getPlatterCount,
+        .getSectorSize = (void *)ne_drive_getSectorSize,
+        .getCapacity = (void *)ne_drive_getCapacity,
+        .readSector = (void *)ne_drive_readSector,
+        .writeSector = (void *)ne_drive_writeSector,
+    };
+
+    nn_addDrive(computer, "drive.img", 4, &genericDrive);
+
     nn_screen *s = nn_newScreen(&alloc, 80, 32, 16, 16, 256);
     nn_addKeyboard(s, "shitty keyboard");
     nn_mountKeyboard(computer, "shitty keyboard", 2);