libmach

1 files changed, 54 insertions, 0 deletions

diff --git a/src/libmach/stabs.c b/src/libmach/stabs.c
new file mode 100644
index 00000000..d34bb864
--- /dev/null
+++ b/src/libmach/stabs.c
@@ -0,0 +1,54 @@
+#include <u.h>
+#include <libc.h>
+#include <mach.h>
+#include "stabs.h"
+
+/*
+http://sources.redhat.com/gdb/onlinedocs/stabs.html
+*/
+
+int
+stabsym(Stab *stabs, int i, StabSym *sym)
+{
+	uchar *p;
+	ulong x;
+
+	if(stabs == nil){
+		werrstr("no stabs");
+		return -1;
+	}
+	if(stabs->e2==nil || stabs->e4==nil){
+		werrstr("no data extractors");
+		return -1;
+	}
+
+	if(i >= stabs->stabsize/12){
+		werrstr("stabs index out of range");
+		return -1;
+	}
+
+	p = stabs->stabbase+i*12;
+	x = stabs->e4(p);
+	if(x == 0)
+		sym->name = nil;
+	else if(x < stabs->strsize)
+		sym->name = stabs->strbase+x;
+	else{
+		werrstr("bad stabs string index");
+		return -1;
+	}
+
+	/*
+	 * In theory, if name ends with a backslash,
+	 * it continues into the next entry.  We could
+	 * rewrite these in place and then zero the next
+	 * few entries, but let's wait until we run across
+	 * some system that generates these.
+	 */
+	sym->type = p[4];
+	sym->other = p[5];
+	sym->desc = stabs->e2(p+6);
+	sym->value = stabs->e4(p+8);
+	return 0;
+}
+