5 files changed, 64 insertions, 22 deletions

diff --git a/mrbgems/mruby-bin-debugger/tools/mrdb/apibreak.c b/mrbgems/mruby-bin-debugger/tools/mrdb/apibreak.c
index 4d139aa76..137f52431 100644
--- a/mrbgems/mruby-bin-debugger/tools/mrdb/apibreak.c
+++ b/mrbgems/mruby-bin-debugger/tools/mrdb/apibreak.c
@@ -14,6 +14,7 @@
 #include <mruby/variable.h>
 #include "mrdberror.h"
 #include "apibreak.h"
+#include "apistring.h"
 
 #define MAX_BREAKPOINTNO (MAX_BREAKPOINT * 1024)
 #define MRB_DEBUG_BP_FILE_OK   (0x0001)
@@ -197,7 +198,7 @@ mrb_debug_set_break_line(mrb_state *mrb, mrb_debug_context *dbg, const char *fil
   }
 
   len = strlen(file) + 1;
-  set_file = (char*)mrb_malloc(mrb, len);
+  set_file = mrb_debug_strdup(mrb, file);
 
   index = dbg->bpnum;
   dbg->bp[index].bpno = dbg->next_bpno;
@@ -207,8 +208,6 @@ mrb_debug_set_break_line(mrb_state *mrb, mrb_debug_context *dbg, const char *fil
   dbg->bp[index].point.linepoint.lineno = lineno;
   dbg->bpnum++;
 
-  strncpy(set_file, file, len);
-
   dbg->bp[index].point.linepoint.file = set_file;
 
   return dbg->bp[index].bpno;
@@ -220,7 +219,6 @@ mrb_debug_set_break_method(mrb_state *mrb, mrb_debug_context *dbg, const char *c
   int32_t index;
   char* set_class;
   char* set_method;
-  size_t len;
 
   if ((mrb == NULL) || (dbg == NULL) || (method_name == NULL)) {
     return MRB_DEBUG_INVALID_ARGUMENT;
@@ -235,18 +233,16 @@ mrb_debug_set_break_method(mrb_state *mrb, mrb_debug_context *dbg, const char *c
   }
 
   if (class_name != NULL) {
-    len = strlen(class_name) + 1;
-    set_class = (char*)mrb_malloc(mrb, len);
-    strncpy(set_class, class_name, len);
+    set_class = mrb_debug_strdup(mrb, class_name);
   }
   else {
     set_class = NULL;
   }
 
-  len = strlen(method_name) + 1;
-  set_method = (char*)mrb_malloc(mrb, len);
-
-  strncpy(set_method, method_name, len);
+  set_method = mrb_debug_strdup(mrb, method_name);
+  if (set_method == NULL) {
+    mrb_free(mrb, set_class);
+  }
 
   index = dbg->bpnum;
   dbg->bp[index].bpno = dbg->next_bpno;
diff --git a/mrbgems/mruby-bin-debugger/tools/mrdb/apilist.c b/mrbgems/mruby-bin-debugger/tools/mrdb/apilist.c
index 66ddfa783..ef80872e5 100644
--- a/mrbgems/mruby-bin-debugger/tools/mrdb/apilist.c
+++ b/mrbgems/mruby-bin-debugger/tools/mrdb/apilist.c
@@ -9,6 +9,7 @@
 #include "mrdb.h"
 #include "mrdberror.h"
 #include "apilist.h"
+#include "apistring.h"
 #include <mruby/compile.h>
 #include <mruby/irep.h>
 #include <mruby/debug.h>
@@ -74,11 +75,7 @@ dirname(mrb_state *mrb, const char *path)
   p = strrchr(path, '/');
   len = p != NULL ? (size_t)(p - path) : strlen(path);
 
-  dir = (char*)mrb_malloc(mrb, len + 1);
-  strncpy(dir, path, len);
-  dir[len] = '\0';
-
-  return dir;
+  return mrb_debug_strndup(mrb, path, len);
 }
 
 static source_file*
@@ -97,8 +94,11 @@ source_file_new(mrb_state *mrb, mrb_debug_context *dbg, char *filename)
   }
 
   file->lineno = 1;
-  file->path = (char*)mrb_malloc(mrb, strlen(filename) + 1);
-  strcpy(file->path, filename);
+  file->path = mrb_debug_strdup(mrb, filename);
+  if (file->path == NULL) {
+    source_file_free(mrb, file);
+    return NULL;
+  }
   return file;
 }
 
diff --git a/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.c b/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.c
new file mode 100644
index 000000000..4cf528feb
--- /dev/null
+++ b/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.c
@@ -0,0 +1,34 @@
+/*
+** apistring.c
+**
+*/
+
+#include <string.h>
+#include "apistring.h"
+
+static size_t
+mrb_debug_strnlen(const char *s, size_t maxlen)
+{
+  const char *p = memchr(s, '\0', maxlen);
+  return p != NULL ? (size_t)(p - s) : maxlen;
+}
+
+char*
+mrb_debug_strndup(mrb_state *mrb, const char *s, size_t size)
+{
+  size_t l = mrb_debug_strnlen(s, size);
+  char *d = mrb_malloc_simple(mrb, l + 1);
+  if (d != NULL) {
+    memcpy(d, s, l);
+    d[l] = '\0';
+  }
+  return d;
+}
+
+char*
+mrb_debug_strdup(mrb_state *mrb, const char *s)
+{
+  size_t z = strlen(s) + 1;
+  char *d = mrb_malloc_simple(mrb, z);
+  return d != NULL ? memcpy(d, s, z) : NULL;
+}
diff --git a/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.h b/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.h
new file mode 100644
index 000000000..e48478d2e
--- /dev/null
+++ b/mrbgems/mruby-bin-debugger/tools/mrdb/apistring.h
@@ -0,0 +1,14 @@
+/*
+ * apistring.h
+ */
+
+#ifndef APISTRING_H_
+#define APISTRING_H_
+
+#include "mruby.h"
+
+/* both functions return a null pointer on failure */
+char *mrb_debug_strndup(mrb_state *mrb, const char *s, size_t size);
+char *mrb_debug_strdup(mrb_state *mrb, const char *s);
+
+#endif /* APISTRING_H_ */
diff --git a/mrbgems/mruby-bin-debugger/tools/mrdb/cmdmisc.c b/mrbgems/mruby-bin-debugger/tools/mrdb/cmdmisc.c
index a05ff9415..fde65fbef 100644
--- a/mrbgems/mruby-bin-debugger/tools/mrdb/cmdmisc.c
+++ b/mrbgems/mruby-bin-debugger/tools/mrdb/cmdmisc.c
@@ -8,6 +8,7 @@
 #include <string.h>
 
 #include "apilist.h"
+#include "apistring.h"
 #include <mruby/compile.h>
 
 typedef struct help_msg {
@@ -232,10 +233,7 @@ parse_filename(mrb_state *mrb, char **sp, listcmd_parser_state *st)
     len = strlen(*sp);
   }
 
-  if (len > 0) {
-    st->filename = (char*)mrb_malloc(mrb, len + 1);
-    strncpy(st->filename, *sp, len);
-    st->filename[len] = '\0';
+  if (len > 0 && (st->filename = mrb_debug_strndup(mrb, *sp, len)) != NULL) {
     *sp += len;
     return TRUE;
   }