explicitly zero extra buffer space added with realloc to silence valgrind warnings

[project/libubox.git] / blob.c

diff --git a/blob.c b/blob.c
index 3bd69fa..4bc67a8 100644 (file)
--- a/blob.c
+++ b/blob.c
@@ -18,8 +18,11 @@
 static bool
 blob_buffer_grow(struct blob_buf *buf, int minlen)
 {
-       buf->buflen += ((minlen / 256) + 1) * 256;
+       int delta = ((minlen / 256) + 1) * 256;
+       buf->buflen += delta;
        buf->buf = realloc(buf->buf, buf->buflen);
+       if (buf->buf)
+               memset(buf->buf + buf->buflen - delta, 0, delta);
        return !!buf->buf;
 }
 
@@ -80,6 +83,14 @@ blob_buf_init(struct blob_buf *buf, int id)
        return 0;
 }
 
+void
+blob_buf_free(struct blob_buf *buf)
+{
+       free(buf->buf);
+       buf->buf = NULL;
+       buf->buflen = 0;
+}
+
 struct blob_attr *
 blob_new(struct blob_buf *buf, int id, int payload)
 {
@@ -131,6 +142,28 @@ static const int blob_type_minlen[BLOB_ATTR_LAST] = {
        [BLOB_ATTR_INT64] = sizeof(uint64_t),
 };
 
+bool
+blob_check_type(const void *ptr, int len, int type)
+{
+       const char *data = ptr;
+
+       if (type >= BLOB_ATTR_LAST)
+               return false;
+
+       if (type >= BLOB_ATTR_INT8 && type <= BLOB_ATTR_INT64) {
+               if (len != blob_type_minlen[type])
+                       return false;
+       } else {
+               if (len < blob_type_minlen[type])
+                       return false;
+       }
+
+       if (type == BLOB_ATTR_STRING && data[len - 1] != 0)
+               return false;
+
+       return true;
+}
+
 int
 blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_attr_info *info, int max)
 {
@@ -142,27 +175,18 @@ blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_at
        blob_for_each_attr(pos, attr, rem) {
                int id = blob_id(pos);
                int len = blob_len(pos);
-               char *pdata;
 
                if (id >= max)
                        continue;
 
                if (info) {
                        int type = info[id].type;
+
                        if (type < BLOB_ATTR_LAST) {
-                               if (type >= BLOB_ATTR_INT8 && type <= BLOB_ATTR_INT64) {
-                                       if (len != blob_type_minlen[type])
-                                               continue;
-                               } else {
-                                       if (len < blob_type_minlen[type])
-                                               continue;
-                               }
+                               if (!blob_check_type(blob_data(pos), len, type))
+                                       continue;
                        }
 
-                       pdata = blob_data(pos);
-                       if (type == BLOB_ATTR_STRING && pdata[len] != 0)
-                               continue;
-
                        if (info[id].minlen && len < info[id].minlen)
                                continue;
 
@@ -180,3 +204,18 @@ blob_parse(struct blob_attr *attr, struct blob_attr **data, const struct blob_at
        }
        return found;
 }
+
+bool
+blob_attr_equal(const struct blob_attr *a1, const struct blob_attr *a2)
+{
+       if (!a1 && !a2)
+               return true;
+
+       if (!a1 || !a2)
+               return false;
+
+       if (blob_pad_len(a1) != blob_pad_len(a2))
+               return false;
+
+       return !memcmp(a1, a2, blob_pad_len(a1));
+}