debugger

1 files changed, 262 insertions, 0 deletions

diff --git a/src/cmd/db/main.c b/src/cmd/db/main.c
new file mode 100644
index 00000000..8e574037
--- /dev/null
+++ b/src/cmd/db/main.c
@@ -0,0 +1,262 @@
+/*
+ * db - main command loop and error/interrupt handling
+ */
+#include "defs.h"
+#include "fns.h"
+
+int wtflag = OREAD;
+BOOL kflag;
+
+BOOL mkfault;
+ADDR maxoff;
+
+int xargc;		/* bullshit */
+
+extern	BOOL	executing;
+extern	int	infile;
+int	exitflg;
+extern	int	eof;
+
+int	alldigs(char*);
+void	fault(void*, char*);
+
+extern	char	*Ipath;
+jmp_buf env;
+static char *errmsg;
+
+Fhdr *symhdr, *corhdr;
+
+void
+usage(void)
+{
+	fprint(2, "usage: db [-kw] [-m machine] [-I dir] [symfile] [pid]\n");
+	exits("usage");
+}
+
+void
+main(int argc, char **argv)
+{
+	int i, omode;
+	char *s;
+	char *name;
+	Fhdr *hdr;
+
+	name = 0;
+	outputinit();
+	maxoff = MAXOFF;
+	omode = OREAD;
+	ARGBEGIN{
+	default:
+		usage();
+	case 'A':
+		abort();
+	case 'k':
+		kflag = 1;
+		break;
+	case 'w':
+		omode = ORDWR;
+		break;
+	case 'I':
+		s = ARGF();
+		if(s == 0)
+			dprint("missing -I argument\n");
+		else
+			Ipath = s;
+		break;
+	case 'm':
+		name = ARGF();
+		if(name == 0)
+			dprint("missing -m argument\n");
+		break;
+	}ARGEND
+
+	/*
+	 * Unix and Plan 9 differ on what the right order of pid, text, and core is.
+	 * I never remember anyway.  Let's just accept them in any order.
+	 */
+	for(i=0; i<argc; i++){
+		if(alldigs(argv[i])){
+			if(pid){
+				dprint("already have pid %d; ignoring pid %d\n", pid, argv[i]);
+				continue;
+			}
+			if(corhdr){
+				dprint("already have core %s; ignoring pid %d\n", corfil, pid);
+				continue;
+			}
+			pid = atoi(argv[i]);
+			continue;
+		}
+		if((hdr = crackhdr(argv[i], omode)) == nil){
+			dprint("crackhdr %s: %r\n", argv[i]);
+			continue;
+		}
+		dprint("%s: %s %s %s\n", argv[i], hdr->aname, hdr->mname, hdr->fname);
+		if(hdr->ftype == FCORE){
+			if(pid){
+				dprint("already have pid %d; ignoring core %s\n", pid, argv[i]);
+				uncrackhdr(hdr);
+				continue;
+			}
+			if(corhdr){
+				dprint("already have core %s; ignoring core %s\n", corfil, argv[i]);
+				uncrackhdr(hdr);
+				continue;
+			}
+			corhdr = hdr;
+			corfil = argv[i];
+		}else{
+			if(symhdr){
+				dprint("already have text %s; ignoring text %s\n", symfil, argv[i]);
+				uncrackhdr(hdr);
+				continue;
+			}
+			symhdr = hdr;
+			symfil = argv[i];
+		}
+	}
+
+	if(symhdr==nil){
+		symfil = "a.out";
+		if(pid){
+			if((s = proctextfile(pid)) != nil){
+				dprint("pid %d: text %s\n", pid, s);
+				symfil = s;
+			}
+		}
+		/* XXX pull command from core */
+
+		if((symhdr = crackhdr(symfil, omode)) == nil){
+			dprint("crackhdr %s: %r\n", symfil);
+			symfil = nil;
+		}
+	}
+
+	if(!mach)
+		mach = machcpu;
+
+	/*
+	 * Set up maps.
+	 */
+	symmap = allocmap();
+	cormap = allocmap();
+	if(symmap == nil || cormap == nil)
+		sysfatal("allocating maps: %r");
+
+	if(symhdr){
+		if(mapfile(symhdr, 0, symmap, nil) < 0)
+			dprint("mapping %s: %r\n", symfil);
+		mapfile(symhdr, 0, cormap, nil);
+	}
+
+	dotmap = dumbmap(-1);
+
+	/*
+	 * show initial state and drop into the execution loop.
+	 */
+	notify(fault);
+	setsym();
+	if(setjmp(env) == 0){
+		if (pid || corhdr)
+			setcor();	/* could get error */
+		if (correg) {
+			dprint("%s\n", mach->exc(cormap, correg));
+			printpc();
+		}
+	}
+
+	setjmp(env);
+	if (executing)
+		delbp();
+	executing = FALSE;
+	for (;;) {
+		flushbuf();
+		if (errmsg) {
+			dprint(errmsg);
+			printc('\n');
+			errmsg = 0;
+			exitflg = 0;
+		}
+		if (mkfault) {
+			mkfault=0;
+			printc('\n');
+			prints(DBNAME);
+		}
+		clrinp();
+		rdc();
+		reread();
+		if (eof) {
+			if (infile == STDIN)
+				done();
+			iclose(-1, 0);
+			eof = 0;
+			longjmp(env, 1);
+		}
+		exitflg = 0;
+		command(0, 0);
+		reread();
+		if (rdc() != '\n')
+			error("newline expected");
+	}
+}
+
+int
+alldigs(char *s)
+{
+	while(*s){
+		if(*s<'0' || '9'<*s)
+			return 0;
+		s++;
+	}
+	return 1;
+}
+
+void
+done(void)
+{
+	if (pid)
+		endpcs();
+	exits(exitflg? "error": 0);
+}
+
+/*
+ * An error occurred; save the message for later printing,
+ * close open files, and reset to main command loop.
+ */
+void
+error(char *n)
+{
+	errmsg = n;
+	iclose(0, 1);
+	oclose();
+	flush();
+	delbp();
+	ending = 0;
+	longjmp(env, 1);
+}
+
+void
+errors(char *m, char *n)
+{
+	static char buf[128];
+
+	sprint(buf, "%s: %s", m, n);
+	error(buf);
+}
+
+/*
+ * An interrupt occurred;
+ * seek to the end of the current file
+ * and remember that there was a fault.
+ */
+void
+fault(void *a, char *s)
+{
+	USED(a);
+	if(strncmp(s, "interrupt", 9) == 0){
+		seek(infile, 0L, 2);
+		mkfault++;
+		noted(NCONT);
+	}
+	noted(NDFLT);
+}