Merge pull request #10316 from poettering/json-api

just the json stuff from #9762

src/basic/json-internal.h

@@ -0,0 +1,57 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#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. */
+#define JSON_VARIANT_MAGIC_TRUE ((JsonVariant*) 1)
+#define JSON_VARIANT_MAGIC_FALSE ((JsonVariant*) 2)
+#define JSON_VARIANT_MAGIC_NULL ((JsonVariant*) 3)
+#define JSON_VARIANT_MAGIC_ZERO_INTEGER ((JsonVariant*) 4)
+#define JSON_VARIANT_MAGIC_ZERO_UNSIGNED ((JsonVariant*) 5)
+#define JSON_VARIANT_MAGIC_ZERO_REAL ((JsonVariant*) 6)
+#define JSON_VARIANT_MAGIC_EMPTY_STRING ((JsonVariant*) 7)
+#define JSON_VARIANT_MAGIC_EMPTY_ARRAY ((JsonVariant*) 8)
+#define JSON_VARIANT_MAGIC_EMPTY_OBJECT ((JsonVariant*) 9)
+
+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);

src/basic/json.h

@@ -0,0 +1,274 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#pragma once
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include "macro.h"
+#include "string-util.h"
+#include "util.h"
+
+/*
+  In case you wonder why we have our own JSON implementation, here are a couple of reasons why this implementation has
+  benefits over various other implementatins:
+
+  - We need support for 64bit signed and unsigned integers, i.e. the full 64,5bit range of -9223372036854775808…18446744073709551615
+  - All our variants are immutable after creation
+  - Special values such as true, false, zero, null, empty strings, empty array, empty objects require zero dynamic memory
+  - Progressive parsing
+  - Our integer/real type implicitly converts, but only if that's safe and loss-lessly possible
+  - There's a "builder" for putting together objects easily in varargs function calls
+  - There's a "dispatcher" for mapping objects to C data structures
+  - Every variant optionally carries parsing location information, which simplifies debugging and parse log error generation
+  - Formatter has color, line, column support
+
+  Limitations:
+  - Doesn't allow embedded NUL in strings
+  - Can't store integers outside of the -9223372036854775808…18446744073709551615 range (it will use 'long double' for
+    values outside this range, which is lossy)
+  - Can't store negative zero (will be treated identical to positive zero, and not retained across serialization)
+  - Can't store non-integer numbers that can't be stored in "long double" losslessly
+  - Allows creation and parsing of objects with duplicate keys. The "dispatcher" will refuse them however. This means
+    we can parse and pass around such objects, but will carefully refuse them when we convert them into our own data.
+
+  (These limitations should be pretty much in line with those of other JSON implementations, in fact might be less
+  limiting in most cases even.)
+*/
+
+typedef struct JsonVariant JsonVariant;
+
+typedef enum JsonVariantType {
+        JSON_VARIANT_STRING,
+        JSON_VARIANT_INTEGER,
+        JSON_VARIANT_UNSIGNED,
+        JSON_VARIANT_REAL,
+        JSON_VARIANT_NUMBER, /* This a pseudo-type: we can never create variants of this type, but we use it as wildcard check for the above three types */
+        JSON_VARIANT_BOOLEAN,
+        JSON_VARIANT_ARRAY,
+        JSON_VARIANT_OBJECT,
+        JSON_VARIANT_NULL,
+        _JSON_VARIANT_TYPE_MAX,
+        _JSON_VARIANT_TYPE_INVALID = -1
+} JsonVariantType;
+
+int json_variant_new_stringn(JsonVariant **ret, const char *s, size_t n);
+int json_variant_new_integer(JsonVariant **ret, intmax_t i);
+int json_variant_new_unsigned(JsonVariant **ret, uintmax_t u);
+int json_variant_new_real(JsonVariant **ret, long double d);
+int json_variant_new_boolean(JsonVariant **ret, bool b);
+int json_variant_new_array(JsonVariant **ret, JsonVariant **array, size_t n);
+int json_variant_new_array_bytes(JsonVariant **ret, const void *p, size_t n);
+int json_variant_new_array_strv(JsonVariant **ret, char **l);
+int json_variant_new_object(JsonVariant **ret, JsonVariant **array, size_t n);
+int json_variant_new_null(JsonVariant **ret);
+
+static inline int json_variant_new_string(JsonVariant **ret, const char *s) {
+        return json_variant_new_stringn(ret, s, strlen_ptr(s));
+}
+
+JsonVariant *json_variant_ref(JsonVariant *v);
+JsonVariant *json_variant_unref(JsonVariant *v);
+void json_variant_unref_many(JsonVariant **array, size_t n);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(JsonVariant *, json_variant_unref);
+
+const char *json_variant_string(JsonVariant *v);
+intmax_t json_variant_integer(JsonVariant *v);
+uintmax_t json_variant_unsigned(JsonVariant *v);
+long double json_variant_real(JsonVariant *v);
+bool json_variant_boolean(JsonVariant *v);
+
+JsonVariantType json_variant_type(JsonVariant *v);
+bool json_variant_has_type(JsonVariant *v, JsonVariantType type);
+
+static inline bool json_variant_is_string(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_STRING);
+}
+
+static inline bool json_variant_is_integer(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_INTEGER);
+}
+
+static inline bool json_variant_is_unsigned(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_UNSIGNED);
+}
+
+static inline bool json_variant_is_real(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_REAL);
+}
+
+static inline bool json_variant_is_number(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_NUMBER);
+}
+
+static inline bool json_variant_is_boolean(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_BOOLEAN);
+}
+
+static inline bool json_variant_is_array(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_ARRAY);
+}
+
+static inline bool json_variant_is_object(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_OBJECT);
+}
+
+static inline bool json_variant_is_null(JsonVariant *v) {
+        return json_variant_has_type(v, JSON_VARIANT_NULL);
+}
+
+bool json_variant_is_negative(JsonVariant *v);
+
+size_t json_variant_elements(JsonVariant *v);
+JsonVariant *json_variant_by_index(JsonVariant *v, size_t index);
+JsonVariant *json_variant_by_key(JsonVariant *v, const char *key);
+JsonVariant *json_variant_by_key_full(JsonVariant *v, const char *key, JsonVariant **ret_key);
+
+bool json_variant_equal(JsonVariant *a, JsonVariant *b);
+
+struct json_variant_foreach_state {
+        JsonVariant *variant;
+        size_t idx;
+};
+
+#define JSON_VARIANT_ARRAY_FOREACH(i, v)                                \
+        for (struct json_variant_foreach_state _state = { (v), 0 };     \
+             _state.idx < json_variant_elements(_state.variant) &&      \
+                     ({ i = json_variant_by_index(_state.variant, _state.idx); \
+                             true; });                                  \
+             _state.idx++)
+
+#define JSON_VARIANT_OBJECT_FOREACH(k, e, v)                            \
+        for (struct json_variant_foreach_state _state = { (v), 0 };     \
+             _state.idx < json_variant_elements(_state.variant) &&      \
+                     ({ k = json_variant_by_index(_state.variant, _state.idx); \
+                             e = json_variant_by_index(_state.variant, _state.idx + 1); \
+                             true; });                                  \
+             _state.idx += 2)
+
+int json_variant_get_source(JsonVariant *v, const char **ret_source, unsigned *ret_line, unsigned *ret_column);
+
+enum {
+        JSON_FORMAT_NEWLINE = 1 << 0, /* suffix with newline */
+        JSON_FORMAT_PRETTY  = 1 << 1, /* add internal whitespace to appeal to human readers */
+        JSON_FORMAT_COLOR   = 1 << 2, /* insert ANSI color sequences */
+        JSON_FORMAT_SOURCE  = 1 << 3, /* prefix with source filename/line/column */
+        JSON_FORMAT_SSE     = 1 << 4, /* prefix/suffix with W3C server-sent events */
+        JSON_FORMAT_SEQ     = 1 << 5, /* prefix/suffix with RFC 7464 application/json-seq */
+};
+
+int json_variant_format(JsonVariant *v, unsigned flags, char **ret);
+void json_variant_dump(JsonVariant *v, unsigned flags, FILE *f, const char *prefix);
+
+int json_parse(const char *string, JsonVariant **ret, unsigned *ret_line, unsigned *ret_column);
+int json_parse_continue(const char **p, JsonVariant **ret, unsigned *ret_line, unsigned *ret_column);
+int json_parse_file(FILE *f, const char *path, JsonVariant **ret, unsigned *ret_line, unsigned *ret_column);
+
+enum {
+        _JSON_BUILD_STRING,
+        _JSON_BUILD_INTEGER,
+        _JSON_BUILD_UNSIGNED,
+        _JSON_BUILD_REAL,
+        _JSON_BUILD_BOOLEAN,
+        _JSON_BUILD_ARRAY_BEGIN,
+        _JSON_BUILD_ARRAY_END,
+        _JSON_BUILD_OBJECT_BEGIN,
+        _JSON_BUILD_OBJECT_END,
+        _JSON_BUILD_PAIR,
+        _JSON_BUILD_NULL,
+        _JSON_BUILD_VARIANT,
+        _JSON_BUILD_LITERAL,
+        _JSON_BUILD_STRV,
+        _JSON_BUILD_MAX,
+};
+
+#define JSON_BUILD_STRING(s) _JSON_BUILD_STRING, ({ const char *_x = s; _x; })
+#define JSON_BUILD_INTEGER(i) _JSON_BUILD_INTEGER, ({ intmax_t _x = i; _x; })
+#define JSON_BUILD_UNSIGNED(u) _JSON_BUILD_UNSIGNED, ({ uintmax_t _x = u; _x; })
+#define JSON_BUILD_REAL(d) _JSON_BUILD_REAL, ({ long double _x = d; _x; })
+#define JSON_BUILD_BOOLEAN(b) _JSON_BUILD_BOOLEAN, ({ bool _x = b; _x; })
+#define JSON_BUILD_ARRAY(...) _JSON_BUILD_ARRAY_BEGIN, __VA_ARGS__, _JSON_BUILD_ARRAY_END
+#define JSON_BUILD_OBJECT(...) _JSON_BUILD_OBJECT_BEGIN, __VA_ARGS__, _JSON_BUILD_OBJECT_END
+#define JSON_BUILD_PAIR(n, ...) _JSON_BUILD_PAIR, ({ const char *_x = n; _x; }), __VA_ARGS__
+#define JSON_BUILD_NULL _JSON_BUILD_NULL
+#define JSON_BUILD_VARIANT(v) _JSON_BUILD_VARIANT, ({ JsonVariant *_x = v; _x; })
+#define JSON_BUILD_LITERAL(l) _JSON_BUILD_LITERAL, ({ const char *_x = l; _x; })
+#define JSON_BUILD_STRV(l) _JSON_BUILD_STRV, ({ char **_x = l; _x; })
+
+int json_build(JsonVariant **ret, ...);
+int json_buildv(JsonVariant **ret, va_list ap);
+
+/* A bitmask of flags used by the dispatch logic. Note that this is a combined bit mask, that is generated from the bit
+ * mask originally passed into json_dispatch(), the individual bitmask associated with the static JsonDispatch callout
+ * entry, as well the bitmask specified for json_log() calls */
+typedef enum JsonDispatchFlags {
+        /* The following three may be set in JsonDispatch's .flags field or the json_dispatch() flags parameter  */
+        JSON_PERMISSIVE = 1 << 0, /* Shall parsing errors be considered fatal for this property? */
+        JSON_MANDATORY  = 1 << 1, /* Should existance of this property be mandatory? */
+        JSON_LOG        = 1 << 2, /* Should the parser log about errors? */
+
+        /* The following two may be passed into log_json() in addition to the three above */
+        JSON_DEBUG      = 1 << 3, /* Indicates that this log message is a debug message */
+        JSON_WARNING    = 1 << 4, /* Indicates that this log message is a warning message */
+} JsonDispatchFlags;
+
+typedef int (*JsonDispatchCallback)(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+
+typedef struct JsonDispatch {
+        const char *name;
+        JsonVariantType type;
+        JsonDispatchCallback callback;
+        size_t offset;
+        JsonDispatchFlags flags;
+} JsonDispatch;
+
+int json_dispatch(JsonVariant *v, const JsonDispatch table[], JsonDispatchCallback bad, JsonDispatchFlags flags, void *userdata);
+
+int json_dispatch_string(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_strv(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_boolean(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_tristate(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_variant(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_integer(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_unsigned(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_uint32(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+int json_dispatch_int32(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata);
+
+assert_cc(sizeof(uintmax_t) == sizeof(uint64_t))
+#define json_dispatch_uint64 json_dispatch_unsigned
+
+assert_cc(sizeof(intmax_t) == sizeof(int64_t))
+#define json_dispatch_int64 json_dispatch_integer
+
+static inline int json_dispatch_level(JsonDispatchFlags flags) {
+
+        /* Did the user request no logging? If so, then never log higher than LOG_DEBUG. Also, if this is marked as
+         * debug message, then also log at debug level. */
+
+        if (!(flags & JSON_LOG) ||
+            (flags & JSON_DEBUG))
+                return LOG_DEBUG;
+
+        /* Are we invoked in permissive mode, or is this explicitly marked as warning message? Then this should be
+         * printed at LOG_WARNING */
+        if (flags & (JSON_PERMISSIVE|JSON_WARNING))
+                return LOG_WARNING;
+
+        /* Otherwise it's an error. */
+        return LOG_ERR;
+}
+
+int json_log_internal(JsonVariant *variant, int level, int error, const char *file, int line, const char *func, const char *format, ...)  _printf_(7, 8);
+
+#define json_log(variant, flags, error, ...)                       \
+        ({                                                              \
+                int _level = json_dispatch_level(flags), _e = (error);    \
+                (log_get_max_level() >= LOG_PRI(_level))                \
+                        ? json_log_internal(variant, _level, _e, __FILE__, __LINE__, __func__, __VA_ARGS__) \
+                        : -abs(_e);                                     \
+        })
+
+const char *json_variant_type_to_string(JsonVariantType t);
+JsonVariantType json_variant_type_from_string(const char *s);

src/basic/meson.build

@@ -99,6 +99,9 @@ basic_sources = files('''
         ioprio.h
         journal-importer.c
         journal-importer.h
+        json-internal.h
+        json.c
+        json.h
         khash.c
         khash.h
         label.c
@@ -313,7 +316,8 @@ libbasic = static_library(
                         libcap,
                         libblkid,
                         libmount,
-                        libselinux],
+                        libselinux,
+                        libm],
         c_args : ['-fvisibility=default'],
         install : false)
 

src/fuzz/fuzz-json.c

@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "fuzz.h"
+#include "json.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        _cleanup_free_ char *out = NULL; /* out should be freed after g */
+        size_t out_size;
+        _cleanup_fclose_ FILE *f = NULL, *g = NULL;
+        _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
+
+        if (size == 0)
+                return 0;
+
+        f = fmemopen((char*) data, size, "re");
+        assert_se(f);
+
+        if (json_parse_file(f, NULL, &v, NULL, NULL) < 0)
+                return 0;
+
+        g = open_memstream(&out, &out_size);
+        assert_se(g);
+
+        json_variant_dump(v, 0, g, NULL);
+        json_variant_dump(v, JSON_FORMAT_PRETTY|JSON_FORMAT_COLOR|JSON_FORMAT_SOURCE, g, NULL);
+
+        return 0;
+}

src/fuzz/meson.build

@@ -37,6 +37,10 @@ fuzzers += [
           libsystemd_network],
          []],
 
+        [['src/fuzz/fuzz-json.c'],
+         [libshared],
+         []],
+
         [['src/fuzz/fuzz-unit-file.c'],
          [libcore,
           libshared],

src/test/meson.build

@@ -191,6 +191,10 @@ tests += [
          [],
          []],
 
+        [['src/test/test-json.c'],
+         [],
+         []],
+
         [['src/test/test-mount-util.c'],
          [],
          []],

src/test/test-json.c

@@ -0,0 +1,411 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <math.h>
+#if HAVE_VALGRIND_VALGRIND_H
+#include <valgrind/valgrind.h>
+#endif
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "json-internal.h"
+#include "json.h"
+#include "string-util.h"
+#include "strv.h"
+#include "util.h"
+
+static void test_tokenizer(const char *data, ...) {
+        unsigned line = 0, column = 0;
+        void *state = NULL;
+        va_list ap;
+
+        va_start(ap, data);
+
+        for (;;) {
+                unsigned token_line, token_column;
+                _cleanup_free_ char *str = NULL;
+                JsonValue v = JSON_VALUE_NULL;
+                int t, tt;
+
+                t = json_tokenize(&data, &str, &v, &token_line, &token_column, &state, &line, &column);
+                tt = va_arg(ap, int);
+
+                assert_se(t == tt);
+
+                if (t == JSON_TOKEN_END || t < 0)
+                        break;
+
+                else if (t == JSON_TOKEN_STRING) {
+                        const char *nn;
+
+                        nn = va_arg(ap, const char *);
+                        assert_se(streq_ptr(nn, str));
+
+                } else if (t == JSON_TOKEN_REAL) {
+                        long double d;
+
+                        d = va_arg(ap, long double);
+
+#if HAVE_VALGRIND_VALGRIND_H
+                        if (!RUNNING_ON_VALGRIND)
+#endif
+                                /* Valgrind doesn't support long double calculations and automatically downgrades to 80bit:
+                                 * http://www.valgrind.org/docs/manual/manual-core.html#manual-core.limits */
+                                assert_se(fabsl(d - v.real) < 0.001L);
+
+                } else if (t == JSON_TOKEN_INTEGER) {
+                        intmax_t i;
+
+                        i = va_arg(ap, intmax_t);
+                        assert_se(i == v.integer);
+
+                } else if (t == JSON_TOKEN_UNSIGNED) {
+                        uintmax_t u;
+
+                        u = va_arg(ap, uintmax_t);
+                        assert_se(u == v.unsig);
+
+                } else if (t == JSON_TOKEN_BOOLEAN) {
+                        bool b;
+
+                        b = va_arg(ap, int);
+                        assert_se(b == v.boolean);
+                }
+        }
+
+        va_end(ap);
+}
+
+typedef void (*Test)(JsonVariant *);
+
+static void test_variant(const char *data, Test test) {
+        _cleanup_(json_variant_unrefp) JsonVariant *v = NULL, *w = NULL;
+        _cleanup_free_ char *s = NULL;
+        int r;
+
+        r = json_parse(data, &v, NULL, NULL);
+        assert_se(r == 0);
+        assert_se(v);
+
+        r = json_variant_format(v, 0, &s);
+        assert_se(r >= 0);
+        assert_se(s);
+
+        log_info("formatted normally: %s\n", s);
+
+        r = json_parse(data, &w, NULL, NULL);
+        assert_se(r == 0);
+        assert_se(w);
+        assert_se(json_variant_has_type(v, json_variant_type(w)));
+        assert_se(json_variant_has_type(w, json_variant_type(v)));
+        assert_se(json_variant_equal(v, w));
+
+        s = mfree(s);
+        w = json_variant_unref(w);
+
+        r = json_variant_format(v, JSON_FORMAT_PRETTY, &s);
+        assert_se(r >= 0);
+        assert_se(s);
+
+        log_info("formatted prettily:\n%s", s);
+
+        r = json_parse(data, &w, NULL, NULL);
+        assert_se(r == 0);
+        assert_se(w);
+
+        assert_se(json_variant_has_type(v, json_variant_type(w)));
+        assert_se(json_variant_has_type(w, json_variant_type(v)));
+        assert_se(json_variant_equal(v, w));
+
+        s = mfree(s);
+        r = json_variant_format(v, JSON_FORMAT_COLOR, &s);
+        assert_se(r >= 0);
+        assert_se(s);
+        printf("Normal with color: %s\n", s);
+
+        s = mfree(s);
+        r = json_variant_format(v, JSON_FORMAT_COLOR|JSON_FORMAT_PRETTY, &s);
+        assert_se(r >= 0);
+        assert_se(s);
+        printf("Pretty with color:\n%s\n", s);
+
+        if (test)
+                test(v);
+}
+
+static void test_1(JsonVariant *v) {
+        JsonVariant *p, *q;
+        unsigned i;
+
+        /* 3 keys + 3 values */
+        assert_se(json_variant_elements(v) == 6);
+
+        /* has k */
+        p = json_variant_by_key(v, "k");
+        assert_se(p && json_variant_type(p) == JSON_VARIANT_STRING);
+
+        /* k equals v */
+        assert_se(streq(json_variant_string(p), "v"));
+
+        /* has foo */
+        p = json_variant_by_key(v, "foo");
+        assert_se(p && json_variant_type(p) == JSON_VARIANT_ARRAY && json_variant_elements(p) == 3);
+
+        /* check  foo[0] = 1, foo[1] = 2, foo[2] = 3 */
+        for (i = 0; i < 3; ++i) {
+                q = json_variant_by_index(p, i);
+                assert_se(q && json_variant_type(q) == JSON_VARIANT_UNSIGNED && json_variant_unsigned(q) == (i+1));
+                assert_se(q && json_variant_has_type(q, JSON_VARIANT_INTEGER) && json_variant_integer(q) == (i+1));
+        }
+
+        /* has bar */
+        p = json_variant_by_key(v, "bar");
+        assert_se(p && json_variant_type(p) == JSON_VARIANT_OBJECT && json_variant_elements(p) == 2);
+
+        /* zap is null */
+        q = json_variant_by_key(p, "zap");
+        assert_se(q && json_variant_type(q) == JSON_VARIANT_NULL);
+}
+
+static void test_2(JsonVariant *v) {
+        JsonVariant *p, *q;
+
+        /* 2 keys + 2 values */
+        assert_se(json_variant_elements(v) == 4);
+
+        /* has mutant */
+        p = json_variant_by_key(v, "mutant");
+        assert_se(p && json_variant_type(p) == JSON_VARIANT_ARRAY && json_variant_elements(p) == 4);
+
+        /* mutant[0] == 1 */
+        q = json_variant_by_index(p, 0);
+        assert_se(q && json_variant_type(q) == JSON_VARIANT_UNSIGNED && json_variant_unsigned(q) == 1);
+        assert_se(q && json_variant_has_type(q, JSON_VARIANT_INTEGER) && json_variant_integer(q) == 1);
+
+        /* mutant[1] == null */
+        q = json_variant_by_index(p, 1);
+        assert_se(q && json_variant_type(q) == JSON_VARIANT_NULL);
+
+        /* mutant[2] == "1" */
+        q = json_variant_by_index(p, 2);
+        assert_se(q && json_variant_type(q) == JSON_VARIANT_STRING && streq(json_variant_string(q), "1"));
+
+        /* mutant[3] == JSON_VARIANT_OBJECT */
+        q = json_variant_by_index(p, 3);
+        assert_se(q && json_variant_type(q) == JSON_VARIANT_OBJECT && json_variant_elements(q) == 2);
+
+        /* has 1 */
+        p = json_variant_by_key(q, "1");
+        assert_se(p && json_variant_type(p) == JSON_VARIANT_ARRAY && json_variant_elements(p) == 2);
+
+        /* "1"[0] == 1 */
+        q = json_variant_by_index(p, 0);
+        assert_se(q && json_variant_type(q) == JSON_VARIANT_UNSIGNED && json_variant_unsigned(q) == 1);
+        assert_se(q && json_variant_has_type(q, JSON_VARIANT_INTEGER) && json_variant_integer(q) == 1);
+
+        /* "1"[1] == "1" */
+        q = json_variant_by_index(p, 1);
+        assert_se(q && json_variant_type(q) == JSON_VARIANT_STRING && streq(json_variant_string(q), "1"));
+
+        /* has thisisaverylongproperty */
+        p = json_variant_by_key(v, "thisisaverylongproperty");
+        assert_se(p && json_variant_type(p) == JSON_VARIANT_REAL && fabs(json_variant_real(p) - 1.27) < 0.001);
+}
+
+
+static void test_zeroes(JsonVariant *v) {
+        size_t i;
+
+        /* Make sure zero is how we expect it. */
+
+        assert_se(json_variant_elements(v) == 13);
+
+        for (i = 0; i < json_variant_elements(v); i++) {
+                JsonVariant *w;
+                size_t j;
+
+                assert_se(w = json_variant_by_index(v, i));
+
+                assert_se(json_variant_integer(w) == 0);
+                assert_se(json_variant_unsigned(w) == 0U);
+
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wfloat-equal"
+                assert_se(json_variant_real(w) == 0.0L);
+#pragma GCC diagnostic pop
+
+                assert_se(json_variant_is_integer(w));
+                assert_se(json_variant_is_unsigned(w));
+                assert_se(json_variant_is_real(w));
+                assert_se(json_variant_is_number(w));
+
+                assert_se(!json_variant_is_negative(w));
+
+                assert_se(IN_SET(json_variant_type(w), JSON_VARIANT_INTEGER, JSON_VARIANT_UNSIGNED, JSON_VARIANT_REAL));
+
+                for (j = 0; j < json_variant_elements(v); j++) {
+                        JsonVariant *q;
+
+                        assert_se(q = json_variant_by_index(v, j));
+
+                        assert_se(json_variant_equal(w, q));
+                }
+        }
+}
+
+static void test_build(void) {
+        _cleanup_(json_variant_unrefp) JsonVariant *a = NULL, *b = NULL;
+        _cleanup_free_ char *s = NULL, *t = NULL;
+
+        assert_se(json_build(&a, JSON_BUILD_STRING("hallo")) >= 0);
+        assert_se(json_build(&b, JSON_BUILD_LITERAL(" \"hallo\"   ")) >= 0);
+        assert_se(json_variant_equal(a, b));
+
+        b = json_variant_unref(b);
+
+        assert_se(json_build(&b, JSON_BUILD_VARIANT(a)) >= 0);
+        assert_se(json_variant_equal(a, b));
+
+        b = json_variant_unref(b);
+        assert_se(json_build(&b, JSON_BUILD_STRING("pief")) >= 0);
+        assert_se(!json_variant_equal(a, b));
+
+        a = json_variant_unref(a);
+        b = json_variant_unref(b);
+
+        assert_se(json_build(&a, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("one", JSON_BUILD_INTEGER(7)),
+                                                   JSON_BUILD_PAIR("two", JSON_BUILD_REAL(2.0)),
+                                                   JSON_BUILD_PAIR("three", JSON_BUILD_INTEGER(0)))) >= 0);
+
+        assert_se(json_build(&b, JSON_BUILD_OBJECT(JSON_BUILD_PAIR("two", JSON_BUILD_INTEGER(2)),
+                                                   JSON_BUILD_PAIR("three", JSON_BUILD_REAL(0)),
+                                                   JSON_BUILD_PAIR("one", JSON_BUILD_REAL(7)))) >= 0);
+
+        assert_se(json_variant_equal(a, b));
+
+        a = json_variant_unref(a);
+        b = json_variant_unref(b);
+
+        assert_se(json_build(&a, JSON_BUILD_ARRAY(JSON_BUILD_OBJECT(JSON_BUILD_PAIR("x", JSON_BUILD_BOOLEAN(true)),
+                                                                    JSON_BUILD_PAIR("y", JSON_BUILD_OBJECT(JSON_BUILD_PAIR("this", JSON_BUILD_NULL)))),
+                                                  JSON_BUILD_VARIANT(NULL),
+                                                  JSON_BUILD_LITERAL(NULL),
+                                                  JSON_BUILD_STRING(NULL),
+                                                  JSON_BUILD_NULL,
+                                                  JSON_BUILD_INTEGER(77),
+                                                  JSON_BUILD_STRV(STRV_MAKE("one", "two", "three", "four")))) >= 0);
+
+        assert_se(json_variant_format(a, 0, &s) >= 0);
+        log_info("GOT: %s\n", s);
+        assert_se(json_parse(s, &b, NULL, NULL) >= 0);
+        assert_se(json_variant_equal(a, b));
+
+        a = json_variant_unref(a);
+        b = json_variant_unref(b);
+
+        assert_se(json_build(&a, JSON_BUILD_REAL(M_PIl)) >= 0);
+
+        s = mfree(s);
+        assert_se(json_variant_format(a, 0, &s) >= 0);
+        log_info("GOT: %s\n", s);
+        assert_se(json_parse(s, &b, NULL, NULL) >= 0);
+        assert_se(json_variant_format(b, 0, &t) >= 0);
+        log_info("GOT: %s\n", t);
+
+        assert_se(streq(s, t));
+
+        a = json_variant_unref(a);
+        b = json_variant_unref(b);
+}
+
+static void test_source(void) {
+        static const char data[] =
+                "\n"
+                "\n"
+                "{\n"
+                "\"foo\" : \"bar\", \n"
+                "\"qüüx\" : [ 1, 2, 3,\n"
+                "4,\n"
+                "5 ],\n"
+                "\"miep\" : { \"hallo\" : 1 },\n"
+                "\n"
+                "\"zzzzzz\" \n"
+                ":\n"
+                "[ true, \n"
+                "false, 7.5, {} ]\n"
+                "}\n";
+
+        _cleanup_fclose_ FILE *f = NULL;
+        _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
+
+        printf("--- original begin ---\n"
+               "%s"
+               "--- original end ---\n", data);
+
+        assert_se(f = fmemopen((void*) data, sizeof(data), "r"));
+
+        assert_se(json_parse_file(f, "waldo", &v, NULL, NULL) >= 0);
+
+        printf("--- non-pretty begin ---\n");
+        json_variant_dump(v, 0, stdout, NULL);
+        printf("\n--- non-pretty end ---\n");
+
+        printf("--- pretty begin ---\n");
+        json_variant_dump(v, JSON_FORMAT_PRETTY|JSON_FORMAT_COLOR|JSON_FORMAT_SOURCE, stdout, NULL);
+        printf("--- pretty end ---\n");
+}
+
+int main(int argc, char *argv[]) {
+
+        log_set_max_level(LOG_DEBUG);
+        log_parse_environment();
+        log_open();
+
+        test_tokenizer("x", -EINVAL);
+        test_tokenizer("", JSON_TOKEN_END);
+        test_tokenizer(" ", JSON_TOKEN_END);
+        test_tokenizer("0", JSON_TOKEN_UNSIGNED, (uintmax_t) 0, JSON_TOKEN_END);
+        test_tokenizer("-0", JSON_TOKEN_INTEGER, (intmax_t) 0, JSON_TOKEN_END);
+        test_tokenizer("1234", JSON_TOKEN_UNSIGNED, (uintmax_t) 1234, JSON_TOKEN_END);
+        test_tokenizer("-1234", JSON_TOKEN_INTEGER, (intmax_t) -1234, JSON_TOKEN_END);
+        test_tokenizer("18446744073709551615", JSON_TOKEN_UNSIGNED, (uintmax_t) UINT64_MAX, JSON_TOKEN_END);
+        test_tokenizer("-9223372036854775808", JSON_TOKEN_INTEGER, (intmax_t) INT64_MIN, JSON_TOKEN_END);
+        test_tokenizer("18446744073709551616", JSON_TOKEN_REAL, (long double) 18446744073709551616.0L, JSON_TOKEN_END);
+        test_tokenizer("-9223372036854775809", JSON_TOKEN_REAL, (long double) -9223372036854775809.0L, JSON_TOKEN_END);
+        test_tokenizer("-1234", JSON_TOKEN_INTEGER, (intmax_t) -1234, JSON_TOKEN_END);
+        test_tokenizer("3.141", JSON_TOKEN_REAL, (long double) 3.141, JSON_TOKEN_END);
+        test_tokenizer("0.0", JSON_TOKEN_REAL, (long double) 0.0, JSON_TOKEN_END);
+        test_tokenizer("7e3", JSON_TOKEN_REAL, (long double) 7e3, JSON_TOKEN_END);
+        test_tokenizer("-7e-3", JSON_TOKEN_REAL, (long double) -7e-3, JSON_TOKEN_END);
+        test_tokenizer("true", JSON_TOKEN_BOOLEAN, true, JSON_TOKEN_END);
+        test_tokenizer("false", JSON_TOKEN_BOOLEAN, false, JSON_TOKEN_END);
+        test_tokenizer("null", JSON_TOKEN_NULL, JSON_TOKEN_END);
+        test_tokenizer("{}", JSON_TOKEN_OBJECT_OPEN, JSON_TOKEN_OBJECT_CLOSE, JSON_TOKEN_END);
+        test_tokenizer("\t {\n} \n", JSON_TOKEN_OBJECT_OPEN, JSON_TOKEN_OBJECT_CLOSE, JSON_TOKEN_END);
+        test_tokenizer("[]", JSON_TOKEN_ARRAY_OPEN, JSON_TOKEN_ARRAY_CLOSE, JSON_TOKEN_END);
+        test_tokenizer("\t [] \n\n", JSON_TOKEN_ARRAY_OPEN, JSON_TOKEN_ARRAY_CLOSE, JSON_TOKEN_END);
+        test_tokenizer("\"\"", JSON_TOKEN_STRING, "", JSON_TOKEN_END);
+        test_tokenizer("\"foo\"", JSON_TOKEN_STRING, "foo", JSON_TOKEN_END);
+        test_tokenizer("\"foo\\nfoo\"", JSON_TOKEN_STRING, "foo\nfoo", JSON_TOKEN_END);
+        test_tokenizer("{\"foo\" : \"bar\"}", JSON_TOKEN_OBJECT_OPEN, JSON_TOKEN_STRING, "foo", JSON_TOKEN_COLON, JSON_TOKEN_STRING, "bar", JSON_TOKEN_OBJECT_CLOSE, JSON_TOKEN_END);
+        test_tokenizer("{\"foo\" : [true, false]}", JSON_TOKEN_OBJECT_OPEN, JSON_TOKEN_STRING, "foo", JSON_TOKEN_COLON, JSON_TOKEN_ARRAY_OPEN, JSON_TOKEN_BOOLEAN, true, JSON_TOKEN_COMMA, JSON_TOKEN_BOOLEAN, false, JSON_TOKEN_ARRAY_CLOSE, JSON_TOKEN_OBJECT_CLOSE, JSON_TOKEN_END);
+        test_tokenizer("\"\xef\xbf\xbd\"", JSON_TOKEN_STRING, "\xef\xbf\xbd", JSON_TOKEN_END);
+        test_tokenizer("\"\\ufffd\"", JSON_TOKEN_STRING, "\xef\xbf\xbd", JSON_TOKEN_END);
+        test_tokenizer("\"\\uf\"", -EINVAL);
+        test_tokenizer("\"\\ud800a\"", -EINVAL);
+        test_tokenizer("\"\\udc00\\udc00\"", -EINVAL);
+        test_tokenizer("\"\\ud801\\udc37\"", JSON_TOKEN_STRING, "\xf0\x90\x90\xb7", JSON_TOKEN_END);
+
+        test_tokenizer("[1, 2, -3]", JSON_TOKEN_ARRAY_OPEN, JSON_TOKEN_UNSIGNED, (uintmax_t) 1, JSON_TOKEN_COMMA, JSON_TOKEN_UNSIGNED, (uintmax_t) 2, JSON_TOKEN_COMMA, JSON_TOKEN_INTEGER, (intmax_t) -3, JSON_TOKEN_ARRAY_CLOSE, JSON_TOKEN_END);
+
+        test_variant("{\"k\": \"v\", \"foo\": [1, 2, 3], \"bar\": {\"zap\": null}}", test_1);
+        test_variant("{\"mutant\": [1, null, \"1\", {\"1\": [1, \"1\"]}], \"thisisaverylongproperty\": 1.27}", test_2);
+        test_variant("{\"foo\" : \"\\uDBFF\\uDFFF\\\"\\uD9FF\\uDFFFFFF\\\"\\uDBFF\\uDFFF\\\"\\uD9FF\\uDFFF\\uDBFF\\uDFFFF\\uDBFF\\uDFFF\\uDBFF\\uDFFF\\uDBFF\\uDFFF\\uDBFF\\uDFFF\\\"\\uD9FF\\uDFFFFF\\\"\\uDBFF\\uDFFF\\\"\\uD9FF\\uDFFF\\uDBFF\\uDFFF\"}", NULL);
+
+        test_variant("[ 0, -0, 0.0, -0.0, 0.000, -0.000, 0e0, -0e0, 0e+0, -0e-0, 0e-0, -0e000, 0e+000 ]", test_zeroes);
+
+        test_build();
+
+        test_source();
+
+        return 0;
+}

tools/oss-fuzz.sh

@@ -48,5 +48,8 @@ zip -jqr $OUT/fuzz-dns-packet_seed_corpus.zip $df/packet
 
 install -Dt $OUT/src/shared/ $build/src/shared/libsystemd-shared-*.so
 
+wget -O $OUT/fuzz-json_seed_corpus.zip https://storage.googleapis.com/skia-fuzzer/oss-fuzz/skjson_seed_corpus.zip
+wget -O $OUT/fuzz-json.dict https://raw.githubusercontent.com/rc0r/afl-fuzz/master/dictionaries/json.dict
+
 find $build -maxdepth 1 -type f -executable -name "fuzz-*" -exec mv {} $OUT \;
 cp src/fuzz/*.options $OUT