X-Git-Url: http://gitweb.hachti.de/?a=blobdiff_plain;ds=sidebyside;f=sw%2Fdisk8%2Fsrc%2Fstructures.h;fp=sw%2Fdisk8%2Fsrc%2Fstructures.h;h=0a72b01c30d355aa3ef57bcc0ffdce9accb7c425;hb=919757fd611e482003ce51f366f6783cab73dea3;hp=0000000000000000000000000000000000000000;hpb=4d042122cf54c44711dcb27547816639243ca87f;p=pdp8.git

diff --git a/sw/disk8/src/structures.h b/sw/disk8/src/structures.h
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+/* 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
+