--- /dev/null
+/* Data structures used in disk8 */
+
+#ifndef D8_STRUCTURES_H
+#define D8_STRUCTURES_H
+
+/* Our basic data type representing one 12 bit word */
+typedef unsigned short int p8word;
+
+/*
+ * This represents one 256 word block system memory or file system block.
+ * Contents can be accessed by the diskblocks[] member as well.
+ */
+typedef union {
+ p8word data [0400];
+} os8_block_t;
+
+
+typedef struct {
+ p8word data[4];
+} os8_file_name_t;
+
+
+typedef union {
+ p8word data[5];
+ struct{
+ struct{
+ unsigned int device_number :4;
+ unsigned int file_size : 8; /* In system blocks */
+ unsigned int dummy: 4;
+ };
+ os8_file_name_t file_name;
+ };
+} what_was_that_t;
+
+
+typedef struct {
+ /* Minus the number of entries in this segment (block) */
+ p8word neg_entries;
+
+ /* Starting block number of first file in this segment */
+ p8word first_file_start;
+
+ /* Link to next segment, 0 if no next segment */
+ p8word next_segment;
+
+ /* Flag word */
+ p8word flag_word;
+
+ /* Minus the number of additional Information words */
+ p8word additional_info_neg;
+
+ /* The directory data */
+ p8word entry_data[0400-06];
+
+ /* End of directory word */
+ p8word end_of_dir;
+
+} os8_directory_segment_t;
+
+
+/*!
+ *\brief OS/8 partition header
+ *
+ * This is the major structure of a device heading.
+ * Normal volumes can start the data at block 007,
+ * system volumes mustn't touch blocks 007-067.
+ */
+typedef struct {
+ /* 000 */ os8_block_t bootblock;
+ /* 001-006 */ os8_directory_segment_t directory[6];
+ /* 007-012 */ os8_block_t keyboard_monitor[4];
+ /* 013-015 */ os8_block_t usr[3];
+ /* 016-025 */ os8_block_t device_handlers[8];
+ /* 026 */ os8_block_t enter_processor;
+ /* 027-050 */ os8_block_t system_scratch[18];
+ /* 051-053 */ os8_block_t command_decoder[3];
+ /* 054-055 */ os8_block_t save_and_date_ovl[2];
+ /* 056 */ os8_block_t mon_errors;
+ /* 057 */ os8_block_t chain_processor;
+ /* 060-063 */ os8_block_t system_odt[4];
+ /* 064 */ os8_block_t reserved_for_expansion;
+ /* 065 */ os8_block_t ccl_reminiscences;
+ /* 066 */ os8_block_t td8e_resident_code;
+ /* 067 */ os8_block_t ccl_overlay;
+} os8_partition_header_t;
+
+
+/********************************************************************************
+ * Following are "private" structures not directly related to OS/8.
+ */
+
+
+typedef union{
+ os8_partition_header_t header;
+ os8_block_t data[4096];
+} os8_partition_t;
+
+typedef enum {IT_UNKNOWN=0, IT_DISK, IT_DECTAPE} image_type_t;
+
+
+/*
+ * File system type
+ * System is for boot images, beginning of data at block 070.
+ */
+#define FST_NORMAL 0
+#define FST_SYSTEM 1
+
+
+/*!
+ *\brief Memory representation of a disk or tape image
+ *
+ * This structure contains all working info and data
+ * associated with a disk or DECTape image.
+ * The image itself \e can contain at most two complete
+ * filesystems as RK05 disks are split into two partitions.
+ */
+typedef struct {
+
+ //! Size of the image in blocks
+ unsigned int size;
+
+ //! Raw byte size of the imported file
+ unsigned int raw_size;
+
+ //! Type of the image, perhaps used later
+ image_type_t type;
+
+ union {
+ //! All blocks in the image
+ os8_block_t data[2*4096];
+ struct {
+ //! The first (and - on tape - only) partition
+ os8_partition_t part0;
+ //! The second partition of a disk
+ os8_partition_t part1;
+ };
+ };
+} image_t;
+
+
+/*
+ * OS/8 file types
+ *
+ * Tentative files should not occur at the moment!
+ */
+typedef enum{
+ FT_EMPTY=0, //!< A \e unused file
+ FT_PERMANENT, //!< A normal fixed file
+ FT_TENTATIVE //!< A Open file (for writing)
+} os8_filetype_t;
+
+/* Maximal number of additional information words in a directory entry */
+#define MAX_ADDITIONAL_INFO 0200
+
+typedef struct os8_dir_entry_s os8_direntry_t;
+
+struct os8_dir_entry_s {
+ os8_filetype_t type; //!< Filetype
+ char name[10]; //!< ASCII file name, not used on empty files
+ int size_blocks; //!< Size of the file in blocks
+ int start_block; //!< First block of the file
+ os8_direntry_t *next; //!< Pointer to next entry
+ os8_direntry_t *prev; //!< Pointer to previous entry
+ p8word additional_info[MAX_ADDITIONAL_INFO];
+};
+
+
+
+typedef struct {
+ os8_direntry_t* entries; //!< Linked list of entries in this directory
+ int additional_info; //!< Size of additional info in each entry
+} directory_t;
+
+
+#endif
+
projects / pdp8.git / blobdiff