1 /* Copyright (c) 1979 Regents of the University of California */ 2 3 /* static char sccsid[] = "@(#)vars.h 1.5 01/26/81"; */ 4 5 #include <stdio.h> 6 7 /* 8 * px - Berkeley Pascal interpreter 9 * 10 * Version 4.0, January 1981 11 * 12 * Original version by Ken Thompson 13 * 14 * Substantial revisions by Bill Joy and Chuck Haley 15 * November-December 1976 16 * 17 * Rewritten for VAX 11/780 by Kirk McKusick 18 * Fall 1978 19 * 20 * Rewritten in ``C'' using libpc by Kirk McKusick 21 * Winter 1981 22 * 23 * Px is described in detail in the "PX 4.0 Implementation Notes" 24 * The source code for px is in several major pieces: 25 * 26 * int.c C main program which reads in interpreter code 27 * interp.c Driver including main interpreter loop and 28 * the interpreter instructions grouped by their 29 * positions in the interpreter table. 30 * except.c Handlers for interpreter specific errors not 31 * included in libpc. 32 * utilities.c Interpreter exit, backtrace, and runtime statistics. 33 * 34 * In addition there are several headers defining mappings for panic 35 * names into codes, and a definition of the interpreter transfer 36 * table. These are made by the script make.ed1 in this directory and 37 * the routine opc.c from ${PASCALDIR}. (see the makefile for details) 38 */ 39 #define PXPFILE "pmon.out" 40 #define BITSPERBYTE 8 41 #define BITSPERLONG (BITSPERBYTE * sizeof(long)) 42 #define HZ 60 43 #define TRUE 1 44 #define FALSE 0 45 #define MAXLVL 20 46 #define NAMSIZ 76 47 #define MAXFILES 32 48 #define PREDEF 2 49 #define STDLVL ((struct iorec *)(0x7ffffff1)) 50 #define GLVL ((struct iorec *)(0x7ffffff0)) 51 #define FILNIL ((struct iorec *)(0)) 52 #define INPUT ((struct iorec *)(&input)) 53 #define OUTPUT ((struct iorec *)(&output)) 54 #define ERR ((struct iorec *)(&_err)) 55 #define PX 0 /* normal run of px */ 56 #define PIX 1 /* load and go */ 57 #define PIPE 2 /* bootstrap via a pipe */ 58 #define releq 0 59 #define relne 2 60 #define rellt 4 61 #define relgt 6 62 #define relle 8 63 #define relge 10 64 65 /* 66 * interrupt and allocation routines 67 */ 68 extern long createtime; 69 extern char *PALLOC(); 70 extern char *malloc(); 71 extern intr(); 72 extern memsize(); 73 extern except(); 74 extern syserr(); 75 extern liberr(); 76 77 /* 78 * stack routines and structures 79 */ 80 struct sze8 { 81 char element[8]; 82 }; 83 extern short pop2(); 84 extern long pop4(); 85 extern double pop8(); 86 extern struct sze8 popsze8(); 87 extern char *pushsp(); 88 89 /* 90 * emulated pc types 91 */ 92 union progcntr { 93 char *cp; 94 unsigned char *ucp; 95 short *sp; 96 unsigned short *usp; 97 long *lp; 98 double *dp; 99 struct hdr *hdrp; 100 }; 101 102 /* 103 * THE RUNTIME DISPLAY 104 * 105 * The entries in the display point to the active static block marks. 106 * The first entry in the display is for the global variables, 107 * then the procedure or function at level one, etc. 108 * Each display entry points to a stack frame as shown: 109 * 110 * base of stack frame 111 * --------------- 112 * | | 113 * | block mark | 114 * | | 115 * --------------- <-- display entry "stp" points here 116 * | | <-- display entry "locvars" points here 117 * | local | 118 * | variables | 119 * | | 120 * --------------- 121 * | | 122 * | expression | 123 * | temporary | 124 * | storage | 125 * | | 126 * - - - - - - - - 127 * 128 * The information in the block mark is thus at positive offsets from 129 * the display.stp pointer entries while the local variables are at negative 130 * offsets from display.locvars. The block mark actually consists of 131 * two parts. The first part is created at CALL and the second at entry, 132 * i.e. BEGIN. Thus: 133 * 134 * ------------------------- 135 * | | 136 * | Saved lino | 137 * | Saved lc | 138 * | Saved dp | 139 * | | 140 * ------------------------- 141 * | | 142 * | Saved (dp) | 143 * | | 144 * | Pointer to current | 145 * | routine header info | 146 * | | 147 * | Saved value of | 148 * | "curfile" | 149 * | | 150 * | Empty tos value | 151 * | | 152 * ------------------------- 153 */ 154 155 /* 156 * runtime display structure 157 */ 158 struct disp { 159 char *locvars; /* pointer to local variables */ 160 struct stack *stp; /* pointer to local stack frame */ 161 }; 162 163 struct stack { 164 char *tos; /* pointer to top of stack frame */ 165 struct iorec *file; /* pointer to active file name */ 166 struct hdr { 167 long framesze; /* number of bytes of local vars */ 168 long nargs; /* number of bytes of arguments */ 169 short tests; /* TRUE => perform runtime tests */ 170 short offset; /* offset of procedure in source file */ 171 char name[1]; /* name of active procedure */ 172 } *entry; 173 struct disp odisp; /* previous display value for this level */ 174 struct disp *dp; /* pointer to active display entry */ 175 union progcntr pc; /* previous location counter */ 176 long lino; /* previous line number */ 177 }; 178 179 union disply { 180 struct disp frame[MAXLVL]; 181 char *raw[2*MAXLVL]; 182 }; 183 184 /* 185 * formal routine structure 186 */ 187 struct formalrtn { 188 char *entryaddr; 189 long cbn; 190 struct disp disp[2*MAXLVL]; 191 }; 192 193 /* 194 * program variables 195 */ 196 extern union disply _display; /* runtime display */ 197 extern struct disp *_dp; /* ptr to active frame */ 198 extern long _lino; /* current line number */ 199 extern int _argc; /* number of passed args */ 200 extern char **_argv; /* values of passed args */ 201 extern long _nodump; /* TRUE => no post mortum dump */ 202 extern long _runtst; /* TRUE => runtime tests */ 203 extern long _mode; /* execl by PX, PIPE, or PIX */ 204 extern long _stlim; /* statement limit */ 205 extern long _stcnt; /* statement count */ 206 extern long _seed; /* random number seed */ 207 extern char *_maxptr; /* maximum valid pointer */ 208 extern char *_minptr; /* minimum valid pointer */ 209 extern long *_pcpcount; /* pointer to pxp buffer */ 210 extern long _cntrs; /* number of counters */ 211 extern long _rtns; /* number of routine cntrs */ 212 213 /* 214 * The file i/o routines maintain a notion of a "current file". 215 * A pointer to this file structure is kept in "curfile". 216 * 217 * file structures 218 */ 219 struct iorechd { 220 char *fileptr; /* ptr to file window */ 221 long lcount; /* number of lines printed */ 222 long llimit; /* maximum number of text lines */ 223 FILE *fbuf; /* FILE ptr */ 224 struct iorec *fchain; /* chain to next file */ 225 struct iorec *flev; /* ptr to associated file variable */ 226 char *pfname; /* ptr to name of file */ 227 short funit; /* file status flags */ 228 short fblk; /* index into active file table */ 229 long fsize; /* size of elements in the file */ 230 char fname[NAMSIZ]; /* name of associated UNIX file */ 231 }; 232 233 struct iorec { 234 char *fileptr; /* ptr to file window */ 235 long lcount; /* number of lines printed */ 236 long llimit; /* maximum number of text lines */ 237 FILE *fbuf; /* FILE ptr */ 238 struct iorec *fchain; /* chain to next file */ 239 struct iorec *flev; /* ptr to associated file variable */ 240 char *pfname; /* ptr to name of file */ 241 short funit; /* file status flags */ 242 short fblk; /* index into active file table */ 243 long fsize; /* size of elements in the file */ 244 char fname[NAMSIZ]; /* name of associated UNIX file */ 245 char buf[BUFSIZ]; /* I/O buffer */ 246 char window[1]; /* file window element */ 247 }; 248 249 /* 250 * unit flags 251 */ 252 #define FDEF 0x80 /* 1 => reserved file name */ 253 #define FTEXT 0x40 /* 1 => text file, process EOLN */ 254 #define FWRITE 0x20 /* 1 => open for writing */ 255 #define FREAD 0x10 /* 1 => open for reading */ 256 #define TEMP 0x08 /* 1 => temporary file */ 257 #define SYNC 0x04 /* 1 => window is out of sync */ 258 #define EOLN 0x02 /* 1 => at end of line */ 259 #define EOFF 0x01 /* 1 => at end of file */ 260 261 /* 262 * file routines 263 */ 264 extern struct iorec *GETNAME(); 265 extern char *MKTEMP(); 266 267 /* 268 * file record variables 269 */ 270 extern struct iorechd _fchain; /* head of active file chain */ 271 extern struct iorec *_actfile[]; /* table of active files */ 272 extern long _filefre; /* last used entry in _actfile */ 273 274 /* 275 * standard files 276 */ 277 extern struct iorechd input; 278 extern struct iorechd output; 279 extern struct iorechd _err; 280 281 /* 282 * Px execution profile array 283 */ 284 #ifdef PROFILE 285 #define NUMOPS 256 286 extern long _profcnts[NUMOPS]; 287 #endif PROFILE 288