libmach

src/libmach/nm.c

@@ -0,0 +1,289 @@
+/*
+ * nm.c -- drive nm
+ */
+#include <u.h>
+#include <libc.h>
+#include <ar.h>
+#include <bio.h>
+#include <mach.h>
+
+enum{
+	CHUNK	=	256	/* must be power of 2 */
+};
+
+char	*errs;			/* exit status */
+char	*filename;		/* current file */
+char	symname[]="__.SYMDEF";	/* table of contents file name */
+int	multifile;		/* processing multiple files */
+int	aflag;
+int	gflag;
+int	hflag;
+int	nflag;
+int	sflag;
+int	uflag;
+
+Symbol	**fnames;		/* file path translation table */
+Symbol	**symptr;
+int	nsym;
+Biobuf	bout;
+
+int	cmp(void*, void*);
+void	error(char*, ...);
+void	execsyms(int);
+void	psym(Symbol*, void*);
+void	printsyms(Symbol**, long);
+void	doar(Biobuf*);
+void	dofile(Biobuf*);
+void	zenter(Symbol*);
+
+void
+main(int argc, char *argv[])
+{
+	int i;
+	Biobuf	*bin;
+
+	Binit(&bout, 1, OWRITE);
+	argv0 = argv[0];
+	ARGBEGIN {
+	case 'a':	aflag = 1; break;
+	case 'g':	gflag = 1; break;
+	case 'h':	hflag = 1; break;
+	case 'n':	nflag = 1; break;
+	case 's':	sflag = 1; break;
+	case 'u':	uflag = 1; break;
+	} ARGEND
+	if (argc > 1)
+		multifile++;
+	for(i=0; i<argc; i++){
+		filename = argv[i];
+		bin = Bopen(filename, OREAD);
+		if(bin == 0){
+			error("cannot open %s", filename);
+			continue;
+		}
+		if (isar(bin))
+			doar(bin);
+		else{
+			Bseek(bin, 0, 0);
+			dofile(bin);
+		}
+		Bterm(bin);
+	}
+	exits(errs);
+}
+
+/*
+ * read an archive file,
+ * processing the symbols for each intermediate file in it.
+ */
+void
+doar(Biobuf *bp)
+{
+	int offset, size, obj;
+	char membername[SARNAME];
+
+	multifile = 1;
+	for (offset = Boffset(bp);;offset += size) {
+		size = nextar(bp, offset, membername);
+		if (size < 0) {
+			error("phase error on ar header %ld", offset);
+			return;
+		}
+		if (size == 0)
+			return;
+		if (strcmp(membername, symname) == 0)
+			continue;
+		obj = objtype(bp, 0);
+		if (obj < 0) {
+			error("inconsistent file %s in %s",
+					membername, filename);
+			return;
+		}
+		if (!readar(bp, obj, offset+size, 1)) {
+			error("invalid symbol reference in file %s",
+					membername);
+			return;
+		}
+		filename = membername;
+		nsym=0;
+		objtraverse(psym, 0);
+		printsyms(symptr, nsym);
+	}
+}
+
+/*
+ * process symbols in a file
+ */
+void
+dofile(Biobuf *bp)
+{
+	int obj;
+
+	obj = objtype(bp, 0);
+	if (obj < 0)
+		execsyms(Bfildes(bp));
+	else
+	if (readobj(bp, obj)) {
+		nsym = 0;
+		objtraverse(psym, 0);
+		printsyms(symptr, nsym);
+	}
+}
+
+/*
+ * comparison routine for sorting the symbol table
+ *	this screws up on 'z' records when aflag == 1
+ */
+int
+cmp(void *vs, void *vt)
+{
+	Symbol **s, **t;
+
+	s = vs;
+	t = vt;
+	if(nflag)
+		if((*s)->value < (*t)->value)
+			return -1;
+		else
+			return (*s)->value > (*t)->value;
+	return strcmp((*s)->name, (*t)->name);
+}
+/*
+ * enter a symbol in the table of filename elements
+ */
+void
+zenter(Symbol *s)
+{
+	static int maxf = 0;
+
+	if (s->value > maxf) {
+		maxf = (s->value+CHUNK-1) &~ (CHUNK-1);
+		fnames = realloc(fnames, (maxf+1)*sizeof(*fnames));
+		if(fnames == 0) {
+			error("out of memory", argv0);
+			exits("memory");
+		}
+	}
+	fnames[s->value] = s;
+}
+
+/*
+ * get the symbol table from an executable file, if it has one
+ */
+void
+execsyms(int fd)
+{
+	Fhdr f;
+	Symbol *s;
+	long n;
+
+	seek(fd, 0, 0);
+	if (crackhdr(fd, &f) == 0) {
+		error("Can't read header for %s", filename);
+		return;
+	}
+	if (syminit(fd, &f) < 0)
+		return;
+	s = symbase(&n);
+	nsym = 0;
+	while(n--)
+		psym(s++, 0);
+
+	printsyms(symptr, nsym);
+}
+
+void
+psym(Symbol *s, void* p)
+{
+	USED(p);
+	switch(s->type) {
+	case 'T':
+	case 'L':
+	case 'D':
+	case 'B':
+		if (uflag)
+			return;
+		if (!aflag && ((s->name[0] == '.' || s->name[0] == '$')))
+			return;
+		break;
+	case 'b':
+	case 'd':
+	case 'l':
+	case 't':
+		if (uflag || gflag)
+			return;
+		if (!aflag && ((s->name[0] == '.' || s->name[0] == '$')))
+			return;
+		break;
+	case 'U':
+		if (gflag)
+			return;
+		break;
+	case 'Z':
+		if (!aflag)
+			return;
+		break;
+	case 'm':
+	case 'f':	/* we only see a 'z' when the following is true*/
+		if(!aflag || uflag || gflag)
+			return;
+		if (strcmp(s->name, ".frame"))
+			zenter(s);
+		break;
+	case 'a':
+	case 'p':
+	case 'z':
+	default:
+		if(!aflag || uflag || gflag)
+			return;
+		break;
+	}
+	symptr = realloc(symptr, (nsym+1)*sizeof(Sym*));
+	if (symptr == 0) {
+		error("out of memory");
+		exits("memory");
+	}
+	symptr[nsym++] = s;
+}
+
+void
+printsyms(Symbol **symptr, long nsym)
+{
+	Symbol *s;
+	char *cp;
+	char path[512];
+
+	if(!sflag)
+		qsort(symptr, nsym, sizeof(*symptr), cmp);
+	while (nsym-- > 0) {
+		s = *symptr++;
+		if (multifile && !hflag)
+			Bprint(&bout, "%s:", filename);
+		if (s->type == 'z') {
+			fileelem(fnames, (uchar *) s->name, path, 512);
+			cp = path;
+		} else
+			cp = s->name;
+		if (s->value || s->type == 'a' || s->type == 'p')
+			Bprint(&bout, "%8lux %c %s\n", s->value, s->type, cp);
+		else
+			Bprint(&bout, "         %c %s\n", s->type, cp);
+	}
+}
+
+void
+error(char *fmt, ...)
+{
+	Fmt f;
+	char buf[128];
+	va_list arg;
+
+	fmtfdinit(&f, 2, buf, sizeof buf);
+	fmtprint(&f, "%s: ", argv0);
+	va_start(arg, fmt);
+	fmtvprint(&f, fmt, arg);
+	va_end(arg);
+	fmtprint(&f, "\n");
+	fmtfdflush(&f);
+	errs = "errors";
+}