xref: /csrg-svn/usr.bin/pascal/px/vars.h (revision 22159)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)vars.h	5.1 (Berkeley) 06/05/85
7  */
8 
9 #include <stdio.h>
10 
11 /*
12  * px - Berkeley Pascal interpreter
13  *
14  * Version 4.0, January 1981
15  *
16  * Original version by Ken Thompson
17  *
18  * Substantial revisions by Bill Joy and Chuck Haley
19  * November-December 1976
20  *
21  * Rewritten for VAX 11/780 by Kirk McKusick
22  * Fall 1978
23  *
24  * Rewritten in ``C'' using libpc by Kirk McKusick
25  * Winter 1981
26  *
27  * Px is described in detail in the "PX 4.0 Implementation Notes"
28  * The source code for px is in several major pieces:
29  *
30  *	int.c		C main program which reads in interpreter code
31  *	interp.c	Driver including main interpreter loop and
32  *			the interpreter instructions grouped by their
33  *			positions in the interpreter table.
34  *	utilities.c	Interpreter exit, backtrace, and runtime statistics.
35  *
36  * In addition there are several headers defining mappings for panic
37  * names into codes, and a definition of the interpreter transfer
38  * table. These are made by the script make.ed1 in this directory and
39  * the routine opc.c from ${PASCALDIR}. (see the makefile for details)
40  */
41 #define PXPFILE		"pmon.out"
42 #define	BITSPERBYTE	8
43 #define	BITSPERLONG	(BITSPERBYTE * sizeof(long))
44 #define HZ		100
45 #define NAMSIZ		76
46 #define MAXFILES	32
47 #define PREDEF		2
48 #ifdef ADDR32
49 #define STDLVL		((struct iorec *)(0x7ffffff1))
50 #define GLVL		((struct iorec *)(0x7ffffff0))
51 #endif ADDR32
52 #ifdef ADDR16
53 #define STDLVL		((struct iorec *)(0xfff1))
54 #define GLVL		((struct iorec *)(0xfff0))
55 #endif ADDR16
56 #define FILNIL		((struct iorec *)(0))
57 #define INPUT		((struct iorec *)(&input))
58 #define OUTPUT		((struct iorec *)(&output))
59 #define ERR		((struct iorec *)(&_err))
60 #define	PX	0	/* normal run of px */
61 #define	PIX	1	/* load and go */
62 #define	PIPE	2	/* bootstrap via a pipe */
63 #define	PDX	3	/* invoked by the debugger "pdx" */
64 #define releq 0
65 #define relne 2
66 #define rellt 4
67 #define relgt 6
68 #define relle 8
69 #define relge 10
70 typedef enum {FALSE, TRUE} bool;
71 
72 /*
73  * interrupt and allocation routines
74  */
75 extern long createtime;
76 extern char *PALLOC();
77 extern char *malloc();
78 extern long time();
79 extern intr();
80 extern memsize();
81 extern syserr();
82 extern liberr();
83 
84 /*
85  * stack routines and structures
86  */
87 struct sze8 {
88 	char element[8];
89 };
90 extern short pop2();
91 extern long pop4();
92 extern double pop8();
93 extern struct sze8 popsze8();
94 extern char *pushsp();
95 
96 /*
97  * emulated pc types
98  */
99 union progcntr {
100 	char *cp;
101 	unsigned char *ucp;
102 	short *sp;
103 	unsigned short *usp;
104 	long *lp;
105 	double *dbp;
106 	struct hdr *hdrp;
107 };
108 
109 /*
110  * THE RUNTIME DISPLAY
111  *
112  * The entries in the display point to the active static block marks.
113  * The first entry in the display is for the global variables,
114  * then the procedure or function at level one, etc.
115  * Each display entry points to a stack frame as shown:
116  *
117  *		base of stack frame
118  *		  ---------------
119  *		  |		|
120  *		  | block mark  |
121  *		  |		|
122  *		  ---------------  <-- display entry "stp" points here
123  *		  |             |  <-- display entry "locvars" points here
124  *		  |   local	|
125  *		  |  variables  |
126  *		  |		|
127  *		  ---------------
128  *		  |		|
129  *		  |  expression |
130  *		  |  temporary  |
131  *		  |  storage	|
132  *		  |		|
133  *		  - - - - - - - -
134  *
135  * The information in the block mark is thus at positive offsets from
136  * the display.stp pointer entries while the local variables are at negative
137  * offsets from display.locvars. The block mark actually consists of
138  * two parts. The first part is created at CALL and the second at entry,
139  * i.e. BEGIN. Thus:
140  *
141  *		-------------------------
142  *		|			|
143  *		|  Saved lino		|
144  *		|  Saved lc		|
145  *		|  Saved dp		|
146  *		|			|
147  *		-------------------------
148  *		|			|
149  *		|  Saved (dp)		|
150  *		|			|
151  *		|  Pointer to current 	|
152  *		|   routine header info	|
153  *		|			|
154  *		|  Saved value of	|
155  *		|   "curfile"		|
156  *		|			|
157  *		|  Empty tos value	|
158  *		|			|
159  *		-------------------------
160  */
161 
162 /*
163  * program variables
164  */
165 extern union display	_display;	/* runtime display */
166 extern struct dispsave	*_dp;		/* ptr to active frame */
167 extern long		_lino;		/* current line number */
168 extern int		_argc;		/* number of passed args */
169 extern char		**_argv;	/* values of passed args */
170 extern bool		_nodump;	/* TRUE => no post mortum dump */
171 extern long		_runtst;	/* TRUE => runtime tests */
172 extern long		_mode;		/* execl by PX, PIPE, or PIX */
173 extern long		_stlim;		/* statement limit */
174 extern long		_stcnt;		/* statement count */
175 extern long		_seed;		/* random number seed */
176 extern char		*_maxptr;	/* maximum valid pointer */
177 extern char		*_minptr;	/* minimum valid pointer */
178 extern long		*_pcpcount;	/* pointer to pxp buffer */
179 extern long		_cntrs;		/* number of counters */
180 extern long		_rtns;		/* number of routine cntrs */
181 
182 /*
183  * The file i/o routines maintain a notion of a "current file".
184  * A pointer to this file structure is kept in "curfile".
185  *
186  * file structures
187  */
188 struct iorechd {
189 	char		*fileptr;	/* ptr to file window */
190 	long		lcount;		/* number of lines printed */
191 	long		llimit;		/* maximum number of text lines */
192 	FILE		*fbuf;		/* FILE ptr */
193 	struct iorec	*fchain;	/* chain to next file */
194 	struct iorec	*flev;		/* ptr to associated file variable */
195 	char		*pfname;	/* ptr to name of file */
196 	short		funit;		/* file status flags */
197 	short		fblk;		/* index into active file table */
198 	long		fsize;		/* size of elements in the file */
199 	char		fname[NAMSIZ];	/* name of associated UNIX file */
200 };
201 
202 struct iorec {
203 	char		*fileptr;	/* ptr to file window */
204 	long		lcount;		/* number of lines printed */
205 	long		llimit;		/* maximum number of text lines */
206 	FILE		*fbuf;		/* FILE ptr */
207 	struct iorec	*fchain;	/* chain to next file */
208 	struct iorec	*flev;		/* ptr to associated file variable */
209 	char		*pfname;	/* ptr to name of file */
210 	short		funit;		/* file status flags */
211 	short		fblk;		/* index into active file table */
212 	long		fsize;		/* size of elements in the file */
213 	char		fname[NAMSIZ];	/* name of associated UNIX file */
214 	char		buf[BUFSIZ];	/* I/O buffer */
215 	char		window[1];	/* file window element */
216 };
217 
218 /*
219  * unit flags
220  */
221 #define	FDEF	0x80	/* 1 => reserved file name */
222 #define	FTEXT	0x40	/* 1 => text file, process EOLN */
223 #define	FWRITE	0x20	/* 1 => open for writing */
224 #define	FREAD	0x10	/* 1 => open for reading */
225 #define	TEMP	0x08	/* 1 => temporary file */
226 #define	SYNC	0x04	/* 1 => window is out of sync */
227 #define	EOLN	0x02	/* 1 => at end of line */
228 #define	EOFF	0x01	/* 1 => at end of file */
229 
230 /*
231  * file routines
232  */
233 extern struct iorec	*GETNAME();
234 extern char		*MKTEMP();
235 
236 /*
237  * file record variables
238  */
239 extern struct iorechd	_fchain;	/* head of active file chain */
240 extern struct iorec	*_actfile[];	/* table of active files */
241 extern long		_filefre;	/* last used entry in _actfile */
242 
243 /*
244  * standard files
245  */
246 extern struct iorechd	input;
247 extern struct iorechd	output;
248 extern struct iorechd	_err;
249 
250 /*
251  * Px execution profile array
252  */
253 #ifdef PROFILE
254 #define	NUMOPS 256
255 extern long _profcnts[NUMOPS];
256 #endif PROFILE
257