1 /*
2  * db - main command loop and error/interrupt handling
3  */
4 #include "defs.h"
5 #include "fns.h"
6 
7 int wtflag = OREAD;
8 BOOL kflag;
9 
10 BOOL mkfault;
11 ADDR maxoff;
12 
13 int xargc;		/* bullshit */
14 
15 extern	BOOL	executing;
16 extern	int	infile;
17 int	exitflg;
18 extern	int	eof;
19 
20 int	alldigs(char*);
21 void	fault(void*, char*);
22 
23 extern	char	*Ipath;
24 jmp_buf env;
25 static char *errmsg;
26 
27 Fhdr *symhdr, *corhdr;
28 
29 void
30 usage(void)
31 {
32 	fprint(2, "usage: db [-kw] [-m machine] [-I dir] [symfile] [pid]\n");
33 	exits("usage");
34 }
35 
36 void
37 main(int argc, char **argv)
38 {
39 	int i, omode;
40 	char *s;
41 	char *name;
42 	Fhdr *hdr;
43 
44 	name = 0;
45 	outputinit();
46 	maxoff = MAXOFF;
47 	omode = OREAD;
48 	ARGBEGIN{
49 	default:
50 		usage();
51 	case 'A':
52 		abort();
53 	case 'k':
54 		kflag = 1;
55 		break;
56 	case 'w':
57 		omode = ORDWR;
58 		break;
59 	case 'I':
60 		s = ARGF();
61 		if(s == 0)
62 			dprint("missing -I argument\n");
63 		else
64 			Ipath = s;
65 		break;
66 	case 'm':
67 		name = ARGF();
68 		if(name == 0)
69 			dprint("missing -m argument\n");
70 		break;
71 	}ARGEND
72 
73 	/*
74 	 * Unix and Plan 9 differ on what the right order of pid, text, and core is.
75 	 * I never remember anyway.  Let's just accept them in any order.
76 	 */
77 	for(i=0; i<argc; i++){
78 		if(alldigs(argv[i])){
79 			if(pid){
80 				dprint("already have pid %d; ignoring pid %d\n", pid, argv[i]);
81 				continue;
82 			}
83 			if(corhdr){
84 				dprint("already have core %s; ignoring pid %d\n", corfil, pid);
85 				continue;
86 			}
87 			pid = atoi(argv[i]);
88 			continue;
89 		}
90 		if((hdr = crackhdr(argv[i], omode)) == nil){
91 			dprint("crackhdr %s: %r\n", argv[i]);
92 			continue;
93 		}
94 		dprint("%s: %s %s %s\n", argv[i], hdr->aname, hdr->mname, hdr->fname);
95 		if(hdr->ftype == FCORE){
96 			if(pid){
97 				dprint("already have pid %d; ignoring core %s\n", pid, argv[i]);
98 				uncrackhdr(hdr);
99 				continue;
100 			}
101 			if(corhdr){
102 				dprint("already have core %s; ignoring core %s\n", corfil, argv[i]);
103 				uncrackhdr(hdr);
104 				continue;
105 			}
106 			corhdr = hdr;
107 			corfil = argv[i];
108 		}else{
109 			if(symhdr){
110 				dprint("already have text %s; ignoring text %s\n", symfil, argv[i]);
111 				uncrackhdr(hdr);
112 				continue;
113 			}
114 			symhdr = hdr;
115 			symfil = argv[i];
116 		}
117 	}
118 
119 	if(symhdr==nil){
120 		symfil = "a.out";
121 		if(pid){
122 			if((s = proctextfile(pid)) != nil){
123 				dprint("pid %d: text %s\n", pid, s);
124 				symfil = s;
125 			}
126 		}
127 		/* XXX pull command from core */
128 
129 		if((symhdr = crackhdr(symfil, omode)) == nil){
130 			dprint("crackhdr %s: %r\n", symfil);
131 			symfil = nil;
132 		}
133 	}
134 
135 	if(!mach)
136 		mach = machcpu;
137 
138 	/*
139 	 * Set up maps.
140 	 */
141 	symmap = allocmap();
142 	cormap = allocmap();
143 	if(symmap == nil || cormap == nil)
144 		sysfatal("allocating maps: %r");
145 
146 	if(symhdr){
147 		if(mapfile(symhdr, 0, symmap, nil) < 0)
148 			dprint("mapping %s: %r\n", symfil);
149 		mapfile(symhdr, 0, cormap, nil);
150 	}
151 
152 	dotmap = dumbmap(-1);
153 
154 	/*
155 	 * show initial state and drop into the execution loop.
156 	 */
157 	notify(fault);
158 	setsym();
159 	if(setjmp(env) == 0){
160 		if (pid || corhdr)
161 			setcor();	/* could get error */
162 		if (correg) {
163 			dprint("%s\n", mach->exc(cormap, correg));
164 			printpc();
165 		}
166 	}
167 
168 	setjmp(env);
169 	if (executing)
170 		delbp();
171 	executing = FALSE;
172 	for (;;) {
173 		flushbuf();
174 		if (errmsg) {
175 			dprint(errmsg);
176 			printc('\n');
177 			errmsg = 0;
178 			exitflg = 0;
179 		}
180 		if (mkfault) {
181 			mkfault=0;
182 			printc('\n');
183 			prints(DBNAME);
184 		}
185 		clrinp();
186 		rdc();
187 		reread();
188 		if (eof) {
189 			if (infile == STDIN)
190 				done();
191 			iclose(-1, 0);
192 			eof = 0;
193 			longjmp(env, 1);
194 		}
195 		exitflg = 0;
196 		command(0, 0);
197 		reread();
198 		if (rdc() != '\n')
199 			error("newline expected");
200 	}
201 }
202 
203 int
204 alldigs(char *s)
205 {
206 	while(*s){
207 		if(*s<'0' || '9'<*s)
208 			return 0;
209 		s++;
210 	}
211 	return 1;
212 }
213 
214 void
215 done(void)
216 {
217 	if (pid)
218 		endpcs();
219 	exits(exitflg? "error": 0);
220 }
221 
222 /*
223  * An error occurred; save the message for later printing,
224  * close open files, and reset to main command loop.
225  */
226 void
227 error(char *n)
228 {
229 	errmsg = n;
230 	iclose(0, 1);
231 	oclose();
232 	flush();
233 	delbp();
234 	ending = 0;
235 	longjmp(env, 1);
236 }
237 
238 void
239 errors(char *m, char *n)
240 {
241 	static char buf[128];
242 
243 	sprint(buf, "%s: %s", m, n);
244 	error(buf);
245 }
246 
247 /*
248  * An interrupt occurred;
249  * seek to the end of the current file
250  * and remember that there was a fault.
251  */
252 void
253 fault(void *a, char *s)
254 {
255 	USED(a);
256 	if(strncmp(s, "interrupt", 9) == 0){
257 		seek(infile, 0L, 2);
258 		mkfault++;
259 		noted(NCONT);
260 	}
261 	noted(NDFLT);
262 }