Adding upstream version 247.3.upstream/247.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 76 insertions, 0 deletions

diff --git a/src/shared/json-internal.h b/src/shared/json-internal.h
new file mode 100644
index 0000000..63afd22
--- /dev/null
+++ b/src/shared/json-internal.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#pragma once
+
+#include "json.h"
+
+/* This header should include all prototypes only the JSON parser itself and
+ * its tests need access to. Normal code consuming the JSON parser should not
+ * interface with this. */
+
+typedef union JsonValue  {
+        /* Encodes a simple value. On x86-64 this structure is 16 bytes wide (as long double is 128bit). */
+        bool boolean;
+        long double real;
+        intmax_t integer;
+        uintmax_t unsig;
+} JsonValue;
+
+/* Let's protect us against accidental structure size changes on our most relevant arch */
+#ifdef __x86_64__
+assert_cc(sizeof(JsonValue) == 16U);
+#endif
+
+#define JSON_VALUE_NULL ((JsonValue) {})
+
+/* We use fake JsonVariant objects for some special values, in order to avoid memory allocations for them. Note that
+ * effectively this means that there are multiple ways to encode the same objects: via these magic values or as
+ * properly allocated JsonVariant. We convert between both on-the-fly as necessary. */
+enum
+{
+ _JSON_VARIANT_MAGIC_TRUE = 1,
+#define JSON_VARIANT_MAGIC_TRUE ((JsonVariant*) _JSON_VARIANT_MAGIC_TRUE)
+ _JSON_VARIANT_MAGIC_FALSE,
+#define JSON_VARIANT_MAGIC_FALSE ((JsonVariant*) _JSON_VARIANT_MAGIC_FALSE)
+ _JSON_VARIANT_MAGIC_NULL,
+#define JSON_VARIANT_MAGIC_NULL ((JsonVariant*) _JSON_VARIANT_MAGIC_NULL)
+ _JSON_VARIANT_MAGIC_ZERO_INTEGER,
+#define JSON_VARIANT_MAGIC_ZERO_INTEGER ((JsonVariant*) _JSON_VARIANT_MAGIC_ZERO_INTEGER)
+ _JSON_VARIANT_MAGIC_ZERO_UNSIGNED,
+#define JSON_VARIANT_MAGIC_ZERO_UNSIGNED ((JsonVariant*) _JSON_VARIANT_MAGIC_ZERO_UNSIGNED)
+ _JSON_VARIANT_MAGIC_ZERO_REAL,
+#define JSON_VARIANT_MAGIC_ZERO_REAL ((JsonVariant*) _JSON_VARIANT_MAGIC_ZERO_REAL)
+ _JSON_VARIANT_MAGIC_EMPTY_STRING,
+#define JSON_VARIANT_MAGIC_EMPTY_STRING ((JsonVariant*) _JSON_VARIANT_MAGIC_EMPTY_STRING)
+ _JSON_VARIANT_MAGIC_EMPTY_ARRAY,
+#define JSON_VARIANT_MAGIC_EMPTY_ARRAY ((JsonVariant*) _JSON_VARIANT_MAGIC_EMPTY_ARRAY)
+ _JSON_VARIANT_MAGIC_EMPTY_OBJECT,
+#define JSON_VARIANT_MAGIC_EMPTY_OBJECT ((JsonVariant*) _JSON_VARIANT_MAGIC_EMPTY_OBJECT)
+ __JSON_VARIANT_MAGIC_MAX
+#define _JSON_VARIANT_MAGIC_MAX ((JsonVariant*) __JSON_VARIANT_MAGIC_MAX)
+};
+
+/* This is only safe as long as we don't define more than 4K magic pointers, i.e. the page size of the simplest
+ * architectures we support. That's because we rely on the fact that malloc() will never allocate from the first memory
+ * page, as it is a faulting page for catching NULL pointer dereferences. */
+assert_cc((unsigned) __JSON_VARIANT_MAGIC_MAX < 4096U);
+
+enum { /* JSON tokens */
+        JSON_TOKEN_END,
+        JSON_TOKEN_COLON,
+        JSON_TOKEN_COMMA,
+        JSON_TOKEN_OBJECT_OPEN,
+        JSON_TOKEN_OBJECT_CLOSE,
+        JSON_TOKEN_ARRAY_OPEN,
+        JSON_TOKEN_ARRAY_CLOSE,
+        JSON_TOKEN_STRING,
+        JSON_TOKEN_REAL,
+        JSON_TOKEN_INTEGER,
+        JSON_TOKEN_UNSIGNED,
+        JSON_TOKEN_BOOLEAN,
+        JSON_TOKEN_NULL,
+        _JSON_TOKEN_MAX,
+        _JSON_TOKEN_INVALID = -1,
+};
+
+int json_tokenize(const char **p, char **ret_string, JsonValue *ret_value, unsigned *ret_line, unsigned *ret_column, void **state, unsigned *line, unsigned *column);