password shredding

Justus had written a patch for this, but the list archive didn't want to
disgorge it, so I wrote one.

2 files changed, 20 insertions, 0 deletions

diff --git a/dlib/dlib.c b/dlib/dlib.c
index f2ef2dd1..a3c59060 100644
--- a/dlib/dlib.c
+++ b/dlib/dlib.c
@@ -134,6 +134,15 @@ char *dStrstrip(char *s)
 }
 
 /*
+ * Clear the contents of the string
+ */
+void dStrshred(char *s)
+{
+   if (s)
+      memset(s, 0, strlen(s));
+}
+
+/*
  * Return a new string of length 'len' filled with 'c' characters
  */
 char *dStrnfill(size_t len, char c)
@@ -336,6 +345,15 @@ void dStr_truncate (Dstr *ds, int len)
 }
 
 /*
+ * Clear a Dstr.
+ */
+void dStr_shred (Dstr *ds)
+{
+   if (ds && ds->sz > 0)
+      memset(ds->str, '\0', ds->sz);
+}
+
+/*
  * Erase a substring.
  */
 void dStr_erase (Dstr *ds, int pos_0, int len)
diff --git a/dlib/dlib.h b/dlib/dlib.h
index ae9c7286..cd612d28 100644
--- a/dlib/dlib.h
+++ b/dlib/dlib.h
@@ -87,6 +87,7 @@ char *dStrstrip(char *s);
 char *dStrnfill(size_t len, char c);
 char *dStrsep(char **orig, const char *delim);
 char *dStristr(const char *haystack, const char *needle);
+void dStrshred(char *s);
 
 /* these are in POSIX 2001. Could be implemented if a port requires it */
 #define dStrcasecmp strcasecmp
@@ -114,6 +115,7 @@ void dStr_append_l (Dstr *ds, const char *s, int l);
 void dStr_insert (Dstr *ds, int pos_0, const char *s);
 void dStr_insert_l (Dstr *ds, int pos_0, const char *s, int l);
 void dStr_truncate (Dstr *ds, int len);
+void dStr_shred (Dstr *ds);
 void dStr_erase (Dstr *ds, int pos_0, int len);
 void dStr_vsprintfa (Dstr *ds, const char *format, va_list argp);
 void dStr_vsprintf (Dstr *ds, const char *format, va_list argp);