1 /*-
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char sccsid[] = "@(#)start.c	8.1 (Berkeley) 06/06/93";
10 #endif /* not lint */
11 
12 /*
13  * Begin execution.
14  *
15  * For px, pstart does a traced exec to read in px and then stop.  But we
16  * want control after px has read in the obj file and before it starts
17  * executing.  The zeroth argument to px tells it to give us control
18  * by sending itself a signal just prior to interpreting.
19  *
20  * We set a "END_BP" breakpoint at the end of the code so that the
21  * process data doesn't disappear after the program terminates.
22  */
23 
24 #include "defs.h"
25 #include <signal.h>
26 #include "process.h"
27 #include "machine.h"
28 #include "main.h"
29 #include "breakpoint.h"
30 #include "source.h"
31 #include "object.h"
32 #include "mappings.h"
33 #include "sym.h"
34 #include "process.rep"
35 
36 #include "pxinfo.h"
37 
38 start(argv, infile, outfile)
39 char **argv;
40 char *infile, *outfile;
41 {
42     char *cmd;
43 
44     setsigtrace();
45     cmd = "px";
46     pstart(process, cmd, argv, infile, outfile);
47     if (process->status == STOPPED) {
48 	TRAPARGS *ap, t;
49 
50 	pcont(process);
51 	if (process->status != STOPPED) {
52 	    if (option('t')) {
53 		quit(process->exitval);
54 	    } else {
55 		panic("px exited with %d", process->exitval);
56 	    }
57 	}
58 #ifdef tahoe
59 	dread(&ap, process->fp, sizeof(ap));
60 	ap = (TRAPARGS *)((unsigned)ap - 4);
61 	dread(&RETLOC, process->fp - 8, sizeof(RETLOC));
62 #else
63 	dread(&ap, process->fp + 2*sizeof(int), sizeof(ap));
64 #endif
65 	dread(&t, ap, sizeof(TRAPARGS));
66 
67 #define NARGS 5
68 #ifdef tahoe
69 #	define STKNARGS (sizeof(int)*(NARGS+1))
70 #	define NARGLOC  t.trp_removed
71 #else
72 #	define STKNARGS (NARGS)
73 #	define NARGLOC  t.nargs
74 #endif
75 	if (NARGLOC != STKNARGS) {
76 	    if (option('t')) {
77 		unsetsigtraces(process);
78 		pcont(process);
79 		quit(process->exitval);
80 	    } else {
81 		panic("start: args out of sync");
82 	    }
83 	}
84 	DISPLAY = t.disp;
85 	DP = t.dp;
86 	ENDOFF = t.objstart;
87 	PCADDR = t.pcaddr;
88 	LOOPADDR = t.loopaddr;
89 	pc = 0;
90 	curfunc = program;
91 	if (objsize != 0) {
92 	    addbp(lastaddr(), END_BP, NIL, NIL, NIL, 0);
93 	}
94     }
95 }
96 
97 /*
98  * Note the termination of the program.  We do this so as to avoid
99  * having the process exit, which would make the values of variables
100  * inaccessible.
101  *
102  * Although the END_BP should really be deleted, it is taken
103  * care of by fixbps the next time the program runs.
104  */
105 
106 endprogram()
107 {
108     if (ss_variables) {
109 	prvarnews();
110     }
111     printf("\nexecution completed\n");
112     curfunc = program;
113     skimsource(srcfilename(pc));
114     curline = lastlinenum;
115     erecover();
116 }
117 
118 /*
119  * set up what signals we want to trace
120  */
121 
122 LOCAL setsigtrace()
123 {
124     register PROCESS *p;
125 
126     p = process;
127     psigtrace(p, SIGINT, TRUE);
128     psigtrace(p, SIGTRAP, TRUE);
129     psigtrace(p, SIGIOT, TRUE);
130     psigtrace(p, SIGILL, TRUE);
131     psigtrace(p, SIGBUS, TRUE);
132 }
133