Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20190403' into staging

[mirror_qemu.git] / qobject / qstring.c

diff --git a/qobject/qstring.c b/qobject/qstring.c
index 05b4bbc2d628d2afeab58c5871ee7ba8e8099048..1c6897df00c764632a6e0457e159647633a0aeda 100644 (file)
--- a/qobject/qstring.c
+++ b/qobject/qstring.c
@@ -12,7 +12,6 @@
 
 #include "qemu/osdep.h"
 #include "qapi/qmp/qstring.h"
-#include "qemu-common.h"
 
 /**
  * qstring_new(): Create a new empty QString
@@ -37,21 +36,23 @@ size_t qstring_get_length(const QString *qstring)
  *
  * Return string reference
  */
-QString *qstring_from_substr(const char *str, int start, int end)
+QString *qstring_from_substr(const char *str, size_t start, size_t end)
 {
     QString *qstring;
 
+    assert(start <= end);
+
     qstring = g_malloc(sizeof(*qstring));
     qobject_init(QOBJECT(qstring), QTYPE_QSTRING);
 
-    qstring->length = end - start + 1;
+    qstring->length = end - start;
     qstring->capacity = qstring->length;
 
+    assert(qstring->capacity < SIZE_MAX);
     qstring->string = g_malloc(qstring->capacity + 1);
     memcpy(qstring->string, str + start, qstring->length);
     qstring->string[qstring->length] = 0;
 
-
     return qstring;
 }
 
@@ -62,13 +63,15 @@ QString *qstring_from_substr(const char *str, int start, int end)
  */
 QString *qstring_from_str(const char *str)
 {
-    return qstring_from_substr(str, 0, strlen(str) - 1);
+    return qstring_from_substr(str, 0, strlen(str));
 }
 
 static void capacity_increase(QString *qstring, size_t len)
 {
     if (qstring->capacity < (qstring->length + len)) {
+        assert(len <= SIZE_MAX - qstring->capacity);
         qstring->capacity += len;
+        assert(qstring->capacity <= SIZE_MAX / 2);
         qstring->capacity *= 2; /* use exponential growth */
 
         qstring->string = g_realloc(qstring->string, qstring->capacity + 1);
@@ -105,17 +108,6 @@ void qstring_append_chr(QString *qstring, int c)
     qstring->string[qstring->length] = 0;
 }
 
-/**
- * qobject_to_qstring(): Convert a QObject to a QString
- */
-QString *qobject_to_qstring(const QObject *obj)
-{
-    if (!obj || qobject_type(obj) != QTYPE_QSTRING) {
-        return NULL;
-    }
-    return container_of(obj, QString, base);
-}
-
 /**
  * qstring_get_str(): Return a pointer to the stored string
  *
@@ -127,13 +119,34 @@ const char *qstring_get_str(const QString *qstring)
     return qstring->string;
 }
 
+/**
+ * qstring_get_try_str(): Return a pointer to the stored string
+ *
+ * NOTE: will return NULL if qstring is not provided.
+ */
+const char *qstring_get_try_str(const QString *qstring)
+{
+    return qstring ? qstring_get_str(qstring) : NULL;
+}
+
+/**
+ * qobject_get_try_str(): Return a pointer to the corresponding string
+ *
+ * NOTE: the string will only be returned if the object is valid, and
+ * its type is QString, otherwise NULL is returned.
+ */
+const char *qobject_get_try_str(const QObject *qstring)
+{
+    return qstring_get_try_str(qobject_to(QString, qstring));
+}
+
 /**
  * qstring_is_equal(): Test whether the two QStrings are equal
  */
 bool qstring_is_equal(const QObject *x, const QObject *y)
 {
-    return !strcmp(qobject_to_qstring(x)->string,
-                   qobject_to_qstring(y)->string);
+    return !strcmp(qobject_to(QString, x)->string,
+                   qobject_to(QString, y)->string);
 }
 
 /**
@@ -145,7 +158,7 @@ void qstring_destroy_obj(QObject *obj)
     QString *qs;
 
     assert(obj != NULL);
-    qs = qobject_to_qstring(obj);
+    qs = qobject_to(QString, obj);
     g_free(qs->string);
     g_free(qs);
 }