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-rw-r--r--src/shared/json-internal.h76
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
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--- /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. This structure is generally 8 bytes wide (as double is 64-bit). */
+ bool boolean;
+ double real;
+ int64_t integer;
+ uint64_t unsig;
+} JsonValue;
+
+/* Let's protect us against accidental structure size changes on our most relevant arch */
+#ifdef __x86_64__
+assert_cc(sizeof(JsonValue) == 8U);
+#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 = -EINVAL,
+};
+
+int json_tokenize(const char **p, char **ret_string, JsonValue *ret_value, unsigned *ret_line, unsigned *ret_column, void **state, unsigned *line, unsigned *column);