json: Use GString instead of QString to accumulate strings

QString supports modifying its string, but it's quite limited: you can
only append.  The remaining callers use it for building an initial
string, never for modifying it later.

Change parse_string() to do build the initial string with GString.
This is another step towards making QString immutable.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-18-armbru@redhat.com>

diff --git a/qobject/json-parser.c b/qobject/json-parser.c
index c0f521b56b108554d642b9a1c7d224a6d2b1d83b..d351039b1015807ee12ec7bae2159d1056e1c580 100644 (file)
--- a/qobject/json-parser.c
+++ b/qobject/json-parser.c
@@ -130,7 +130,7 @@ static int cvt4hex(const char *s)
 static QString *parse_string(JSONParserContext *ctxt, JSONToken *token)
 {
     const char *ptr = token->str;
-    QString *str;
+    GString *str;
     char quote;
     const char *beg;
     int cp, trailing;
@@ -140,7 +140,7 @@ static QString *parse_string(JSONParserContext *ctxt, JSONToken *token)
 
     assert(*ptr == '"' || *ptr == '\'');
     quote = *ptr++;
-    str = qstring_new();
+    str = g_string_new(NULL);
 
     while (*ptr != quote) {
         assert(*ptr);
@@ -149,31 +149,31 @@ static QString *parse_string(JSONParserContext *ctxt, JSONToken *token)
             beg = ptr++;
             switch (*ptr++) {
             case '"':
-                qstring_append_chr(str, '"');
+                g_string_append_c(str, '"');
                 break;
             case '\'':
-                qstring_append_chr(str, '\'');
+                g_string_append_c(str, '\'');
                 break;
             case '\\':
-                qstring_append_chr(str, '\\');
+                g_string_append_c(str, '\\');
                 break;
             case '/':
-                qstring_append_chr(str, '/');
+                g_string_append_c(str, '/');
                 break;
             case 'b':
-                qstring_append_chr(str, '\b');
+                g_string_append_c(str, '\b');
                 break;
             case 'f':
-                qstring_append_chr(str, '\f');
+                g_string_append_c(str, '\f');
                 break;
             case 'n':
-                qstring_append_chr(str, '\n');
+                g_string_append_c(str, '\n');
                 break;
             case 'r':
-                qstring_append_chr(str, '\r');
+                g_string_append_c(str, '\r');
                 break;
             case 't':
-                qstring_append_chr(str, '\t');
+                g_string_append_c(str, '\t');
                 break;
             case 'u':
                 cp = cvt4hex(ptr);
@@ -200,7 +200,7 @@ static QString *parse_string(JSONParserContext *ctxt, JSONToken *token)
                                 (int)(ptr - beg), beg);
                     goto out;
                 }
-                qstring_append(str, utf8_buf);
+                g_string_append(str, utf8_buf);
                 break;
             default:
                 parse_error(ctxt, token, "invalid escape sequence in string");
@@ -225,14 +225,14 @@ static QString *parse_string(JSONParserContext *ctxt, JSONToken *token)
             ptr = end;
             len = mod_utf8_encode(utf8_buf, sizeof(utf8_buf), cp);
             assert(len >= 0);
-            qstring_append(str, utf8_buf);
+            g_string_append(str, utf8_buf);
         }
     }
 
-    return str;
+    return qstring_from_gstring(str);
 
 out:
-    qobject_unref(str);
+    g_string_free(str, true);
     return NULL;
 }