diff options
Diffstat (limited to 'mixlib/xmix_device.c')
| -rw-r--r-- | mixlib/xmix_device.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/mixlib/xmix_device.c b/mixlib/xmix_device.c index 8d4084c..6fb085f 100644 --- a/mixlib/xmix_device.c +++ b/mixlib/xmix_device.c @@ -143,14 +143,20 @@ read_ (mix_device_t *dev, mix_word_t *block) } static gboolean -ioc_ (mix_device_t *dev, mix_short_t arg) +ioc_ (mix_device_t *dev, mix_short_t arg, mix_word_t val) { int m; FILE *file; + long diskblock; m = mix_short_magnitude(arg); if (mix_short_is_negative(arg)) m = -m; m *= sizeof (mix_word_t) * SIZES_[dev->type]; + + diskblock = mix_word_magnitude(val); + if (mix_word_is_negative(val)) diskblock = -diskblock; + diskblock *= sizeof (mix_word_t) * SIZES_[dev->type]; + file = mix_io_to_FILE (GET_CHANNEL_(dev)); if (dev->type >= mix_dev_TAPE_0 && dev->type <= mix_dev_TAPE_7) @@ -160,12 +166,13 @@ ioc_ (mix_device_t *dev, mix_short_t arg) } if (dev->type >= mix_dev_DISK_0 && dev->type <= mix_dev_DISK_7) { - if (m == 0) return FALSE; - // position disk + // move read/write head to block + if (m != 0 || diskblock < 0) return FALSE; + else fseek (file, diskblock, SEEK_SET); } if (dev->type == mix_dev_PAPER_TAPE) { - if (m == 0) return FALSE; + if (m != 0) return FALSE; rewind (file); } return TRUE; |