wsutil: Improve UTF-8 APIs for debugging

In particular add an UTF-8 specific wslog API that should
make it easier to interpret invalid encodings.

2 files changed, 33 insertions, 15 deletions

diff --git a/wsutil/wmem/wmem_strbuf.c b/wsutil/wmem/wmem_strbuf.c
index 00edf26264..bb1ea41c83 100644
--- a/wsutil/wmem/wmem_strbuf.c
+++ b/wsutil/wmem/wmem_strbuf.c
@@ -252,6 +252,23 @@ wmem_strbuf_append_unichar(wmem_strbuf_t *strbuf, const gunichar c)
     }
 }
 
+static const char hex[16] = { '0', '1', '2', '3', '4', '5', '6', '7',
+                              '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
+
+void
+wmem_strbuf_append_hex(wmem_strbuf_t *strbuf, uint8_t ch)
+{
+    wmem_strbuf_grow(strbuf, 4);
+
+    if (!strbuf->max_size || WMEM_STRBUF_ROOM(strbuf) >= 4) {
+        strbuf->str[strbuf->len++] = '\\';
+        strbuf->str[strbuf->len++] = 'x';
+        strbuf->str[strbuf->len++] = hex[(ch >> 4) & 0xF];
+        strbuf->str[strbuf->len++] = hex[(ch >> 0) & 0xF];
+        strbuf->str[strbuf->len] = '\0';
+    }
+}
+
 void
 wmem_strbuf_truncate(wmem_strbuf_t *strbuf, const size_t len)
 {
@@ -332,14 +349,16 @@ wmem_strbuf_destroy(wmem_strbuf_t *strbuf)
 }
 
 bool
-wmem_strbuf_sanitize_utf8(wmem_strbuf_t *strbuf)
+wmem_strbuf_utf8_validate(wmem_strbuf_t *strbuf, const char **endptr)
 {
-    if (g_utf8_validate(strbuf->str, -1, NULL)) {
-        return false;
-    }
+    return g_utf8_validate(strbuf->str, strbuf->len, endptr);
+}
 
+void
+wmem_strbuf_utf8_make_valid(wmem_strbuf_t *strbuf)
+{
     /* Sanitize the contents to a temporary string. */
-    char *tmp = g_utf8_make_valid(strbuf->str, -1);
+    char *tmp = g_utf8_make_valid(strbuf->str, strbuf->len);
 
     /* Reset the strbuf, keeping the backing memory allocation */
     *strbuf->str = '\0';
@@ -348,8 +367,6 @@ wmem_strbuf_sanitize_utf8(wmem_strbuf_t *strbuf)
     /* Copy the temporary string to the strbuf. */
     wmem_strbuf_append(strbuf, tmp);
     g_free(tmp);
-
-    return true;
 }
 
 /*
diff --git a/wsutil/wmem/wmem_strbuf.h b/wsutil/wmem/wmem_strbuf.h
index c691eeb160..e9acc215c7 100644
--- a/wsutil/wmem/wmem_strbuf.h
+++ b/wsutil/wmem/wmem_strbuf.h
@@ -106,6 +106,10 @@ wmem_strbuf_append_unichar(wmem_strbuf_t *strbuf, const gunichar c);
 
 WS_DLL_PUBLIC
 void
+wmem_strbuf_append_hex(wmem_strbuf_t *strbuf, uint8_t);
+
+WS_DLL_PUBLIC
+void
 wmem_strbuf_truncate(wmem_strbuf_t *strbuf, const size_t len);
 
 WS_DLL_PUBLIC
@@ -137,16 +141,13 @@ WS_DLL_PUBLIC
 void
 wmem_strbuf_destroy(wmem_strbuf_t *strbuf);
 
-/** Check the UTF-8 encoded strbuf for validity and sanitize the contents if needed,
- * by replacing encoding errors with unicode replacement character. This function is
- * intended for debugging purposes and is not optimized for speed.
- *
- * @param strbuf the strbuf to validate
- * @return true if the string was sanitized, false otherwise
- */
 WS_DLL_PUBLIC
 bool
-wmem_strbuf_sanitize_utf8(wmem_strbuf_t *strbuf);
+wmem_strbuf_utf8_validate(wmem_strbuf_t *strbuf, const char **endptr);
+
+WS_DLL_PUBLIC
+void
+wmem_strbuf_utf8_make_valid(wmem_strbuf_t *strbuf);
 
 /**   @}
  *  @} */