mbed-mruby

Diff: src/backtrace.c

Revision:

0:158c61bb030f

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/backtrace.c	Wed Mar 25 17:36:16 2015 +0000
@@ -0,0 +1,202 @@
+/*
+** backtrace.c -
+**
+** See Copyright Notice in mruby.h
+*/
+
+#include <stdarg.h>
+#include "mruby.h"
+#include "mruby/variable.h"
+#include "mruby/proc.h"
+#include "mruby/array.h"
+#include "mruby/string.h"
+#include "mruby/class.h"
+#include "mruby/debug.h"
+#include "mruby/error.h"
+
+#ifdef ENABLE_STDIO
+
+typedef void (*output_stream_func)(mrb_state*, void*, int, const char*, ...);
+
+static void
+print_backtrace_i(mrb_state *mrb, void *stream, int level, const char *format, ...)
+{
+  va_list ap;
+
+  va_start(ap, format);
+  vfprintf((FILE*)stream, format, ap);
+  va_end(ap);
+}
+
+
+#define MIN_BUFSIZE 127
+
+static void
+get_backtrace_i(mrb_state *mrb, void *stream, int level, const char *format, ...)
+{
+  va_list ap;
+  mrb_value ary, str;
+  int ai;
+
+  if (level > 0) {
+    return;
+  }
+
+  ai = mrb_gc_arena_save(mrb);
+  ary = mrb_obj_value((struct RArray*)stream);
+
+  va_start(ap, format);
+  str = mrb_str_new(mrb, 0, vsnprintf(NULL, 0, format, ap) + 1);
+  va_end(ap);
+
+  va_start(ap, format);
+  vsnprintf(RSTRING_PTR(str), RSTRING_LEN(str), format, ap);
+  va_end(ap);
+
+  mrb_str_resize(mrb, str, RSTRING_LEN(str) - 1);
+  mrb_ary_push(mrb, ary, str);
+  mrb_gc_arena_restore(mrb, ai);
+}
+
+static void
+output_backtrace(mrb_state *mrb, mrb_int ciidx, mrb_code *pc0, output_stream_func func, void *stream)
+{
+  mrb_callinfo *ci;
+  const char *filename, *method, *sep;
+  int i, lineno, tracehead = 1;
+
+  if (ciidx >= mrb->c->ciend - mrb->c->cibase)
+    ciidx = 10; /* ciidx is broken... */
+
+  for (i = ciidx; i >= 0; i--) {
+    ci = &mrb->c->cibase[i];
+    filename = NULL;
+
+    if (!ci->proc) continue;
+    if (MRB_PROC_CFUNC_P(ci->proc)) {
+      continue;
+    }
+    else {
+      mrb_irep *irep = ci->proc->body.irep;
+      mrb_code *pc;
+
+      if (mrb->c->cibase[i].err) {
+        pc = mrb->c->cibase[i].err;
+      }
+      else if (i+1 <= ciidx) {
+        pc = mrb->c->cibase[i+1].pc - 1;
+      }
+      else {
+        pc = pc0;
+      }
+      filename = mrb_debug_get_filename(irep, (uint32_t)(pc - irep->iseq));
+      lineno = mrb_debug_get_line(irep, (uint32_t)(pc - irep->iseq));
+    }
+    if (lineno == -1) continue;
+    if (ci->target_class == ci->proc->target_class)
+      sep = ".";
+    else
+      sep = "#";
+
+    if (!filename) {
+      filename = "(unknown)";
+    }
+
+    if (tracehead) {
+      func(mrb, stream, 1, "trace:\n");
+      tracehead = 0;
+    }
+    method = mrb_sym2name(mrb, ci->mid);
+    if (method) {
+      const char *cn = mrb_class_name(mrb, ci->proc->target_class);
+
+      if (cn) {
+        func(mrb, stream, 1, "\t[%d] ", i);
+        func(mrb, stream, 0, "%s:%d:in %s%s%s", filename, lineno, cn, sep, method);
+        func(mrb, stream, 1, "\n");
+      }
+      else {
+        func(mrb, stream, 1, "\t[%d] ", i);
+        func(mrb, stream, 0, "%s:%d:in %s", filename, lineno, method);
+        func(mrb, stream, 1, "\n");
+      }
+    }
+    else {
+        func(mrb, stream, 1, "\t[%d] ", i);
+        func(mrb, stream, 0, "%s:%d", filename, lineno);
+        func(mrb, stream, 1, "\n");
+    }
+  }
+}
+
+static void
+exc_output_backtrace(mrb_state *mrb, struct RObject *exc, output_stream_func func, void *stream)
+{
+  output_backtrace(mrb, mrb_fixnum(mrb_obj_iv_get(mrb, exc, mrb_intern_lit(mrb, "ciidx"))),
+                   (mrb_code*)mrb_cptr(mrb_obj_iv_get(mrb, exc, mrb_intern_lit(mrb, "lastpc"))),
+                   func, stream);
+}
+
+/* mrb_print_backtrace/mrb_get_backtrace:
+
+   function to retrieve backtrace information from the exception.
+   note that if you call method after the exception, call stack will be
+   overwritten.  So invoke these functions just after detecting exceptions.
+*/
+
+MRB_API void
+mrb_print_backtrace(mrb_state *mrb)
+{
+  if (!mrb->exc || mrb_obj_is_kind_of(mrb, mrb_obj_value(mrb->exc), E_SYSSTACK_ERROR)) {
+    return;
+  }
+  exc_output_backtrace(mrb, mrb->exc, print_backtrace_i, (void*)stderr);
+}
+
+MRB_API mrb_value
+mrb_exc_backtrace(mrb_state *mrb, mrb_value self)
+{
+  mrb_value ary;
+
+  ary = mrb_ary_new(mrb);
+  exc_output_backtrace(mrb, mrb_obj_ptr(self), get_backtrace_i, (void*)mrb_ary_ptr(ary));
+
+  return ary;
+}
+
+MRB_API mrb_value
+mrb_get_backtrace(mrb_state *mrb)
+{
+  mrb_value ary;
+  mrb_callinfo *ci = mrb->c->ci;
+  mrb_code *pc = ci->pc;
+  mrb_int ciidx = (mrb_int)(ci - mrb->c->cibase - 1);
+
+  if (ciidx < 0) ciidx = 0;
+  ary = mrb_ary_new(mrb);
+  output_backtrace(mrb, ciidx, pc, get_backtrace_i, (void*)mrb_ary_ptr(ary));
+
+  return ary;
+}
+
+#else
+
+MRB_API void
+mrb_print_backtrace(mrb_state *mrb)
+{
+}
+
+MRB_API mrb_value
+mrb_exc_backtrace(mrb_state *mrb, mrb_value self)
+{
+  return mrb_ary_new(mrb);
+}
+
+MRB_API mrb_value
+mrb_get_backtrace(mrb_state *mrb)
+{
+  return mrb_ary_new(mrb);
+}
+
+#endif
+