Telodendria/src/Json.c

859 lines
18 KiB
C

/*
* Copyright (C) 2022 Jordan Bancino <@jordan:bancino.net>
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <Json.h>
#include <Util.h>
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
struct JsonValue
{
JsonType type;
union
{
HashMap *object;
Array *array;
char *string;
long integer;
double floating;
int boolean:1;
} as;
};
typedef enum JsonToken
{
TOKEN_UNKNOWN,
TOKEN_COLON,
TOKEN_COMMA,
TOKEN_OBJECT_OPEN,
TOKEN_OBJECT_CLOSE,
TOKEN_ARRAY_OPEN,
TOKEN_ARRAY_CLOSE,
TOKEN_STRING,
TOKEN_INTEGER,
TOKEN_FLOAT,
TOKEN_BOOLEAN,
TOKEN_NULL,
TOKEN_EOF
} JsonToken;
typedef struct JsonParserState
{
FILE *stream;
JsonToken tokenType;
char *token;
} JsonParserState;
JsonType
JsonValueType(JsonValue * value)
{
if (!value)
{
return JSON_NULL;
}
return value->type;
}
static JsonValue *
JsonValueAllocate(void)
{
return malloc(sizeof(JsonValue));
}
JsonValue *
JsonValueObject(HashMap * object)
{
JsonValue *value;
if (!object)
{
return NULL;
}
value = JsonValueAllocate();
if (!value)
{
return NULL;
}
value->type = JSON_OBJECT;
value->as.object = object;
return value;
}
HashMap *
JsonValueAsObject(JsonValue * value)
{
if (!value || value->type != JSON_OBJECT)
{
return NULL;
}
return value->as.object;
}
JsonValue *
JsonValueArray(Array * array)
{
JsonValue *value;
if (!array)
{
return NULL;
}
value = JsonValueAllocate();
if (!value)
{
return NULL;
}
value->type = JSON_ARRAY;
value->as.array = array;
return value;
}
Array *
JsonValueAsArray(JsonValue * value)
{
if (!value || value->type != JSON_ARRAY)
{
return NULL;
}
return value->as.array;
}
JsonValue *
JsonValueString(char *string)
{
JsonValue *value;
if (!string)
{
return NULL;
}
value = JsonValueAllocate();
if (!value)
{
return NULL;
}
value->type = JSON_STRING;
value->as.string = string;
return value;
}
char *
JsonValueAsString(JsonValue * value)
{
if (!value || value->type != JSON_STRING)
{
return NULL;
}
return value->as.string;
}
JsonValue *
JsonValueInteger(long integer)
{
JsonValue *value;
value = JsonValueAllocate();
if (!value)
{
return 0;
}
value->type = JSON_INTEGER;
value->as.integer = integer;
return value;
}
long
JsonValueAsInteger(JsonValue * value)
{
if (!value || value->type != JSON_INTEGER)
{
return 0;
}
return value->as.integer;
}
JsonValue *
JsonValueFloat(double floating)
{
JsonValue *value;
value = JsonValueAllocate();
if (!value)
{
return NULL;
}
value->type = JSON_FLOAT;
value->as.floating = floating;
return value;
}
double
JsonValueAsFloat(JsonValue * value)
{
if (!value || value->type != JSON_FLOAT)
{
return 0;
}
return value->as.floating;
}
JsonValue *
JsonValueBoolean(int boolean)
{
JsonValue *value;
value = JsonValueAllocate();
if (!value)
{
return NULL;
}
value->type = JSON_BOOLEAN;
value->as.boolean = boolean;
return value;
}
int
JsonValueAsBoolean(JsonValue * value)
{
if (!value || value->type != JSON_BOOLEAN)
{
return 0;
}
return value->as.boolean;
}
JsonValue *
JsonValueNull(void)
{
JsonValue *value;
value = JsonValueAllocate();
if (!value)
{
return NULL;
}
value->type = JSON_NULL;
return value;
}
void
JsonValueFree(JsonValue * value)
{
size_t i;
Array *arr;
if (!value)
{
return;
}
switch (value->type)
{
case JSON_OBJECT:
JsonFree(value->as.object);
break;
case JSON_ARRAY:
arr = value->as.array;
for (i = 0; i < ArraySize(arr); i++)
{
JsonValueFree((JsonValue *) ArrayGet(arr, i));
}
ArrayFree(arr);
break;
case JSON_STRING:
free(value->as.string);
break;
default:
break;
}
free(value);
}
void
JsonEncodeString(const char *str, FILE * out)
{
size_t i;
char c;
fputc('"', out);
i = 0;
while ((c = str[i]) != '\0')
{
switch (c)
{
case '\\':
case '"':
case '/':
fputc('\\', out);
fputc(c, out);
break;
case '\b':
fputs("\\b", out);
break;
case '\t':
fputs("\\t", out);
break;
case '\n':
fputs("\\n", out);
break;
case '\f':
fputs("\\f", out);
break;
case '\r':
fputs("\\r", out);
break;
default: /* Assume UTF-8 input */
/*
* RFC 4627: "All Unicode characters may be placed
* within the quotation marks except for the characters
* that must be escaped: quotation mark, reverse solidus,
* and the control characters (U+0000 through U+001F)."
*
* This technically covers the above cases for backspace,
* tab, newline, feed, and carriage return characters,
* but we can save bytes if we encode those as their
* more human-readable representation.
*/
if (c <= 0x001F)
{
printf("\\u%04x", c);
}
else
{
fputc(c, out);
}
break;
}
i++;
}
fputc('"', out);
}
static char *
JsonDecodeString(FILE * in)
{
const size_t strBlockSize = 16;
size_t i;
size_t len;
size_t allocated;
char *str;
char c;
char a[5];
unsigned long utf8;
char *utf8Ptr;
len = 0;
allocated = strBlockSize;
str = malloc(allocated * sizeof(char));
if (!str)
{
return NULL;
}
while ((c = fgetc(in)) != EOF)
{
if (c <= 0x001F)
{
/* Bad byte; these must be escaped */
free(str);
return NULL;
}
switch (c)
{
case '"':
str[len] = '\0';
return str;
break;
case '\\':
c = fgetc(in);
switch (c)
{
case '\\':
case '"':
case '/':
a[0] = c;
a[1] = '\0';
break;
case 'b':
a[0] = '\b';
a[1] = '\0';
break;
case 't':
a[0] = '\t';
a[1] = '\0';
break;
case 'n':
a[0] = '\n';
a[1] = '\0';
break;
case 'f':
a[0] = '\f';
a[1] = '\0';
break;
case 'r':
a[0] = '\r';
a[1] = '\0';
break;
case 'u':
/* Read \uXXXX point into a 4-byte buffer */
if (fscanf(in, "%04lx", &utf8) != 1)
{
/* Bad hex value */
free(str);
return NULL;
}
if (utf8 == 0)
{
/*
* We read in a \u0000, null. There is no
* circumstance in which putting a null
* character into our buffer will end well.
*
* There's also really no legitimate use
* for the null character in our JSON anyway;
* it's likely an attempted exploit.
*
* So lets just strip it out. Don't even
* include it in the string. There should be
* no harm in ignoring it.
*/
continue;
}
/* Encode the 4-byte UTF-8 buffer into a series
* of 1-byte characters */
utf8Ptr = UtilUtf8Encode(utf8);
if (!utf8Ptr)
{
/* Mem error */
free(str);
return NULL;
}
/* Move the output of UtilUtf8Encode() into our
* local buffer */
strcpy(a, utf8Ptr);
free(utf8Ptr);
break;
default:
/* Bad escape value */
free(str);
return NULL;
}
break;
default:
a[0] = c;
a[1] = '\0';
break;
}
/* Append buffer a */
i = 0;
while (a[i] != '\0')
{
if (len >= allocated)
{
char *tmp;
allocated += strBlockSize;
tmp = realloc(str, allocated * sizeof(char));
if (!tmp)
{
free(str);
return NULL;
}
str = tmp;
}
str[len] = a[i];
len++;
i++;
}
}
free(str);
return NULL;
}
void
JsonEncodeValue(JsonValue * value, FILE * out)
{
size_t i;
size_t len;
Array *arr;
switch (value->type)
{
case JSON_OBJECT:
JsonEncode(value->as.object, out);
break;
case JSON_ARRAY:
arr = value->as.array;
len = ArraySize(arr);
fputc('[', out);
for (i = 0; i < len; i++)
{
JsonEncodeValue(ArrayGet(arr, i), out);
if (i < len - 1)
{
fputc(',', out);
}
}
fputc(']', out);
break;
case JSON_STRING:
JsonEncodeString(value->as.string, out);
break;
case JSON_INTEGER:
fprintf(out, "%ld", value->as.integer);
break;
case JSON_FLOAT:
fprintf(out, "%f", value->as.floating);
break;
case JSON_BOOLEAN:
if (value->as.boolean)
{
fputs("true", out);
}
else
{
fputs("false", out);
}
break;
case JSON_NULL:
fputs("null", out);
break;
default:
return;
}
}
int
JsonEncode(HashMap * object, FILE * out)
{
size_t index;
size_t count;
char *key;
JsonValue *value;
if (!object || !out)
{
return 0;
}
count = 0;
while (HashMapIterate(object, &key, (void **) &value))
{
count++;
}
fputc('{', out);
index = 0;
while (HashMapIterate(object, &key, (void **) &value))
{
JsonEncodeString(key, out);
fputc(':', out);
JsonEncodeValue(value, out);
if (index < count - 1)
{
fputc(',', out);
}
index++;
}
fputc('}', out);
return 1;
}
void
JsonFree(HashMap * object)
{
char *key;
JsonValue *value;
while (HashMapIterate(object, &key, (void **) &value))
{
JsonValueFree(value);
}
HashMapFree(object);
}
static int
JsonConsumeWhitespace(JsonParserState * state)
{
int c;
while (isspace(c = fgetc(state->stream)));
return c;
}
static void
JsonTokenSeek(JsonParserState * state)
{
int c = JsonConsumeWhitespace(state);
if (feof(state->stream))
{
state->tokenType = TOKEN_EOF;
return;
}
if (state->token)
{
free(state->token);
state->token = NULL;
}
switch (c)
{
case ':':
state->tokenType = TOKEN_COLON;
break;
case ',':
state->tokenType = TOKEN_COMMA;
break;
case '{':
state->tokenType = TOKEN_OBJECT_OPEN;
break;
case '}':
state->tokenType = TOKEN_OBJECT_CLOSE;
break;
case '[':
state->tokenType = TOKEN_ARRAY_OPEN;
break;
case ']':
state->tokenType = TOKEN_ARRAY_CLOSE;
break;
case '"':
state->token = JsonDecodeString(state->stream);
if (!state->token)
{
state->tokenType = TOKEN_EOF;
return;
}
state->tokenType = TOKEN_STRING;
break;
default:
if (c == '-' || isdigit(c))
{
int isFloat = 0;
size_t allocated = 16;
size_t len = 1;
state->token = malloc(allocated);
if (!state->token)
{
state->tokenType = TOKEN_EOF;
return;
}
state->token[0] = c;
while ((c = fgetc(state->stream)) != EOF)
{
if (c == '.')
{
if (len > 1)
{
isFloat = 1;
}
else
{
state->tokenType = TOKEN_UNKNOWN;
return;
}
}
if (!isdigit(c))
{
ungetc(c, state->stream);
break;
}
if (len >= allocated)
{
char *tmp;
allocated += 16;
tmp = realloc(state->token, allocated);
if (!tmp)
{
state->tokenType = TOKEN_EOF;
return;
}
state->token = tmp;
}
state->token[len] = c;
len++;
}
if (state->token[len - 1] == '.')
{
state->tokenType = TOKEN_UNKNOWN;
return;
}
state->token[len] = '\0';
if (isFloat)
{
state->tokenType = TOKEN_FLOAT;
}
else
{
state->tokenType = TOKEN_INTEGER;
}
}
else
{
state->token = malloc(8);
if (!state->token)
{
state->tokenType = TOKEN_EOF;
return;
}
switch (c)
{
case 't':
fgets(state->token, 5, state->stream);
if (!strcmp("true", state->token))
{
state->tokenType = TOKEN_BOOLEAN;
}
else
{
state->tokenType = TOKEN_UNKNOWN;
}
break;
case 'f':
fgets(state->token, 6, state->stream);
if (!strcmp("false", state->token))
{
state->tokenType = TOKEN_BOOLEAN;
}
else
{
state->tokenType = TOKEN_UNKNOWN;
}
break;
case 'n':
fgets(state->token, 5, state->stream);
if (strcmp("null", state->token))
{
state->tokenType = TOKEN_NULL;
}
else
{
state->tokenType = TOKEN_UNKNOWN;
}
break;
default:
state->tokenType = TOKEN_UNKNOWN;
break;
}
}
}
}
static int
JsonExpect(JsonParserState * state, JsonToken token)
{
return state->tokenType == token;
}
static HashMap *
JsonDecodeObject(JsonParserState * state)
{
return NULL;
}
static Array *
JsonDecodeArray(JsonParserState * state)
{
return NULL;
}
HashMap *
JsonDecode(FILE * stream)
{
JsonParserState state;
state.stream = stream;
state.token = NULL;
return JsonDecodeObject(&state);
}