Stage 16: Config Module
Recap
In the previous stages, we have updated our server to operate with HTTP messages. We have implemented HTTP request parsing in Stage 14 and sending the output as HTTP response messages in Stage 15.
Learning Objectives
- Implementation of multiple cores
- Use JSON file to set-up server configuration
- Implement reverse proxy and URL redirecting
Introduction
Till now, we have implemented a single core architecture i.e all listeners created were attached to the same core. In this stage, we are updating the server to operate with multiple cores thus enhancing the throughput. It allows the efficient processing of multiple requests concurrently. Now, all the listeners to be created are duplicated across each of the cores.
A JSON configuration file is used to configure the number of cores to be created and the listeners to be attached to those. It also specifies the type of each of the port for a given a req_path.
For example:
json
"listeners": [{ "host": "0.0.0.0", "port": 8003 }],
"routes": [
{
"req_path": "/",
"type": "redirect",
"http_status_code": 302,
"redirect_url": "https://expserver.github.io"
}
]- Listener configuration ensures that any client connecting to the server's IP address on port 8003 will be able to send requests.
routesdefines the behavior of the server when handling specific request paths. Here, when a client sends a request to the root path (/), the server responds with a302status code, redirecting the client to the URLhttps://expserver.github.io.
We are also introducing the redirecting server and re-introducing the reverse proxy functionality.
File Structure
Design
A new module xps_config is added for reading the JSON configuration file and storing the parsed data in the structs. It also implements a lookup of the configuration to determine the appropriate server and route for an incoming request. It also matchs the listeners and hostnames.
The session module is updated to incorporate the lookup of configuration while processing the request. The appropriate functionality is executed with respsect to the request type obtained from the lookup. The redirect server and reverse proxy server are implemented here.
The main.c is updated to create multiple cores. Each of the listeners mentioned in the configuration file is duplicated and added to all the cores created.
Implementation
As the server configuration is present in the form of JSON data, a parser is required for parsing this data. It parses JSON data into C structures and manipulate or extract the data in a structured manner. Add the below given files in the specified location for ensuring the parsing of provided configuration:
expserver/src/lib/parson/parson.h
```c
/*
SPDX-License-Identifier: MIT
Parson 1.5.3 (https://github.com/kgabis/parson)
Copyright (c) 2012 - 2023 Krzysztof Gabis
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 substantial 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.
*/
#ifndef parson_parson_h
#define parson_parson_h
#ifdef __cplusplus
extern "C"
{
#endif
#if 0
} /* unconfuse xcode */
#endif
#define PARSON_VERSION_MAJOR 1
#define PARSON_VERSION_MINOR 5
#define PARSON_VERSION_PATCH 3
#define PARSON_VERSION_STRING "1.5.3"
#include <stddef.h> /* size_t */
/* Types and enums */
typedef struct json_object_t JSON_Object;
typedef struct json_array_t JSON_Array;
typedef struct json_value_t JSON_Value;
enum json_value_type {
JSONError = -1,
JSONNull = 1,
JSONString = 2,
JSONNumber = 3,
JSONObject = 4,
JSONArray = 5,
JSONBoolean = 6
};
typedef int JSON_Value_Type;
enum json_result_t {
JSONSuccess = 0,
JSONFailure = -1
};
typedef int JSON_Status;
typedef void * (*JSON_Malloc_Function)(size_t);
typedef void (*JSON_Free_Function)(void *);
/* A function used for serializing numbers (see json_set_number_serialization_function).
If 'buf' is null then it should return number of bytes that would've been written
(but not more than PARSON_NUM_BUF_SIZE).
*/
typedef int (*JSON_Number_Serialization_Function)(double num, char *buf);
/* Call only once, before calling any other function from parson API. If not called, malloc and free
from stdlib will be used for all allocations */
void json_set_allocation_functions(JSON_Malloc_Function malloc_fun, JSON_Free_Function free_fun);
/* Sets if slashes should be escaped or not when serializing JSON. By default slashes are escaped.
This function sets a global setting and is not thread safe. */
void json_set_escape_slashes(int escape_slashes);
/* Sets float format used for serialization of numbers.
Make sure it can't serialize to a string longer than PARSON_NUM_BUF_SIZE.
If format is null then the default format is used. */
void json_set_float_serialization_format(const char *format);
/* Sets a function that will be used for serialization of numbers.
If function is null then the default serialization function is used. */
void json_set_number_serialization_function(JSON_Number_Serialization_Function fun);
/* Parses first JSON value in a file, returns NULL in case of error */
JSON_Value * json_parse_file(const char *filename);
/* Parses first JSON value in a file and ignores comments (/ * * / and //),
returns NULL in case of error */
JSON_Value * json_parse_file_with_comments(const char *filename);
/* Parses first JSON value in a string, returns NULL in case of error */
JSON_Value * json_parse_string(const char *string);
/* Parses first JSON value in a string and ignores comments (/ * * / and //),
returns NULL in case of error */
JSON_Value * json_parse_string_with_comments(const char *string);
/* Serialization */
size_t json_serialization_size(const JSON_Value *value); /* returns 0 on fail */
JSON_Status json_serialize_to_buffer(const JSON_Value *value, char *buf, size_t buf_size_in_bytes);
JSON_Status json_serialize_to_file(const JSON_Value *value, const char *filename);
char * json_serialize_to_string(const JSON_Value *value);
/* Pretty serialization */
size_t json_serialization_size_pretty(const JSON_Value *value); /* returns 0 on fail */
JSON_Status json_serialize_to_buffer_pretty(const JSON_Value *value, char *buf, size_t buf_size_in_bytes);
JSON_Status json_serialize_to_file_pretty(const JSON_Value *value, const char *filename);
char * json_serialize_to_string_pretty(const JSON_Value *value);
void json_free_serialized_string(char *string); /* frees string from json_serialize_to_string and json_serialize_to_string_pretty */
/* Comparing */
int json_value_equals(const JSON_Value *a, const JSON_Value *b);
/* Validation
This is *NOT* JSON Schema. It validates json by checking if object have identically
named fields with matching types.
For example schema {"name":"", "age":0} will validate
{"name":"Joe", "age":25} and {"name":"Joe", "age":25, "gender":"m"},
but not {"name":"Joe"} or {"name":"Joe", "age":"Cucumber"}.
In case of arrays, only first value in schema is checked against all values in tested array.
Empty objects ({}) validate all objects, empty arrays ([]) validate all arrays,
null validates values of every type.
*/
JSON_Status json_validate(const JSON_Value *schema, const JSON_Value *value);
/*
* JSON Object
*/
JSON_Value * json_object_get_value (const JSON_Object *object, const char *name);
const char * json_object_get_string (const JSON_Object *object, const char *name);
size_t json_object_get_string_len(const JSON_Object *object, const char *name); /* doesn't account for last null character */
JSON_Object * json_object_get_object (const JSON_Object *object, const char *name);
JSON_Array * json_object_get_array (const JSON_Object *object, const char *name);
double json_object_get_number (const JSON_Object *object, const char *name); /* returns 0 on fail */
int json_object_get_boolean(const JSON_Object *object, const char *name); /* returns -1 on fail */
/* dotget functions enable addressing values with dot notation in nested objects,
just like in structs or c++/java/c# objects (e.g. objectA.objectB.value).
Because valid names in JSON can contain dots, some values may be inaccessible
this way. */
JSON_Value * json_object_dotget_value (const JSON_Object *object, const char *name);
const char * json_object_dotget_string (const JSON_Object *object, const char *name);
size_t json_object_dotget_string_len(const JSON_Object *object, const char *name); /* doesn't account for last null character */
JSON_Object * json_object_dotget_object (const JSON_Object *object, const char *name);
JSON_Array * json_object_dotget_array (const JSON_Object *object, const char *name);
double json_object_dotget_number (const JSON_Object *object, const char *name); /* returns 0 on fail */
int json_object_dotget_boolean(const JSON_Object *object, const char *name); /* returns -1 on fail */
/* Functions to get available names */
size_t json_object_get_count (const JSON_Object *object);
const char * json_object_get_name (const JSON_Object *object, size_t index);
JSON_Value * json_object_get_value_at(const JSON_Object *object, size_t index);
JSON_Value * json_object_get_wrapping_value(const JSON_Object *object);
/* Functions to check if object has a value with a specific name. Returned value is 1 if object has
* a value and 0 if it doesn't. dothas functions behave exactly like dotget functions. */
int json_object_has_value (const JSON_Object *object, const char *name);
int json_object_has_value_of_type(const JSON_Object *object, const char *name, JSON_Value_Type type);
int json_object_dothas_value (const JSON_Object *object, const char *name);
int json_object_dothas_value_of_type(const JSON_Object *object, const char *name, JSON_Value_Type type);
/* Creates new name-value pair or frees and replaces old value with a new one.
* json_object_set_value does not copy passed value so it shouldn't be freed afterwards. */
JSON_Status json_object_set_value(JSON_Object *object, const char *name, JSON_Value *value);
JSON_Status json_object_set_string(JSON_Object *object, const char *name, const char *string);
JSON_Status json_object_set_string_with_len(JSON_Object *object, const char *name, const char *string, size_t len); /* length shouldn't include last null character */
JSON_Status json_object_set_number(JSON_Object *object, const char *name, double number);
JSON_Status json_object_set_boolean(JSON_Object *object, const char *name, int boolean);
JSON_Status json_object_set_null(JSON_Object *object, const char *name);
/* Works like dotget functions, but creates whole hierarchy if necessary.
* json_object_dotset_value does not copy passed value so it shouldn't be freed afterwards. */
JSON_Status json_object_dotset_value(JSON_Object *object, const char *name, JSON_Value *value);
JSON_Status json_object_dotset_string(JSON_Object *object, const char *name, const char *string);
JSON_Status json_object_dotset_string_with_len(JSON_Object *object, const char *name, const char *string, size_t len); /* length shouldn't include last null character */
JSON_Status json_object_dotset_number(JSON_Object *object, const char *name, double number);
JSON_Status json_object_dotset_boolean(JSON_Object *object, const char *name, int boolean);
JSON_Status json_object_dotset_null(JSON_Object *object, const char *name);
/* Frees and removes name-value pair */
JSON_Status json_object_remove(JSON_Object *object, const char *name);
/* Works like dotget function, but removes name-value pair only on exact match. */
JSON_Status json_object_dotremove(JSON_Object *object, const char *key);
/* Removes all name-value pairs in object */
JSON_Status json_object_clear(JSON_Object *object);
/*
*JSON Array
*/
JSON_Value * json_array_get_value (const JSON_Array *array, size_t index);
const char * json_array_get_string (const JSON_Array *array, size_t index);
size_t json_array_get_string_len(const JSON_Array *array, size_t index); /* doesn't account for last null character */
JSON_Object * json_array_get_object (const JSON_Array *array, size_t index);
JSON_Array * json_array_get_array (const JSON_Array *array, size_t index);
double json_array_get_number (const JSON_Array *array, size_t index); /* returns 0 on fail */
int json_array_get_boolean(const JSON_Array *array, size_t index); /* returns -1 on fail */
size_t json_array_get_count (const JSON_Array *array);
JSON_Value * json_array_get_wrapping_value(const JSON_Array *array);
/* Frees and removes value at given index, does nothing and returns JSONFailure if index doesn't exist.
* Order of values in array may change during execution. */
JSON_Status json_array_remove(JSON_Array *array, size_t i);
/* Frees and removes from array value at given index and replaces it with given one.
* Does nothing and returns JSONFailure if index doesn't exist.
* json_array_replace_value does not copy passed value so it shouldn't be freed afterwards. */
JSON_Status json_array_replace_value(JSON_Array *array, size_t i, JSON_Value *value);
JSON_Status json_array_replace_string(JSON_Array *array, size_t i, const char* string);
JSON_Status json_array_replace_string_with_len(JSON_Array *array, size_t i, const char *string, size_t len); /* length shouldn't include last null character */
JSON_Status json_array_replace_number(JSON_Array *array, size_t i, double number);
JSON_Status json_array_replace_boolean(JSON_Array *array, size_t i, int boolean);
JSON_Status json_array_replace_null(JSON_Array *array, size_t i);
/* Frees and removes all values from array */
JSON_Status json_array_clear(JSON_Array *array);
/* Appends new value at the end of array.
* json_array_append_value does not copy passed value so it shouldn't be freed afterwards. */
JSON_Status json_array_append_value(JSON_Array *array, JSON_Value *value);
JSON_Status json_array_append_string(JSON_Array *array, const char *string);
JSON_Status json_array_append_string_with_len(JSON_Array *array, const char *string, size_t len); /* length shouldn't include last null character */
JSON_Status json_array_append_number(JSON_Array *array, double number);
JSON_Status json_array_append_boolean(JSON_Array *array, int boolean);
JSON_Status json_array_append_null(JSON_Array *array);
/*
*JSON Value
*/
JSON_Value * json_value_init_object (void);
JSON_Value * json_value_init_array (void);
JSON_Value * json_value_init_string (const char *string); /* copies passed string */
JSON_Value * json_value_init_string_with_len(const char *string, size_t length); /* copies passed string, length shouldn't include last null character */
JSON_Value * json_value_init_number (double number);
JSON_Value * json_value_init_boolean(int boolean);
JSON_Value * json_value_init_null (void);
JSON_Value * json_value_deep_copy (const JSON_Value *value);
void json_value_free (JSON_Value *value);
JSON_Value_Type json_value_get_type (const JSON_Value *value);
JSON_Object * json_value_get_object (const JSON_Value *value);
JSON_Array * json_value_get_array (const JSON_Value *value);
const char * json_value_get_string (const JSON_Value *value);
size_t json_value_get_string_len(const JSON_Value *value); /* doesn't account for last null character */
double json_value_get_number (const JSON_Value *value);
int json_value_get_boolean(const JSON_Value *value);
JSON_Value * json_value_get_parent (const JSON_Value *value);
/* Same as above, but shorter */
JSON_Value_Type json_type (const JSON_Value *value);
JSON_Object * json_object (const JSON_Value *value);
JSON_Array * json_array (const JSON_Value *value);
const char * json_string (const JSON_Value *value);
size_t json_string_len(const JSON_Value *value); /* doesn't account for last null character */
double json_number (const JSON_Value *value);
int json_boolean(const JSON_Value *value);
#ifdef __cplusplus
}
#endif
#endif
```
expserver/src/lib/parson/parson.c
```c
/*
SPDX-License-Identifier: MIT
Parson 1.5.3 (https://github.com/kgabis/parson)
Copyright (c) 2012 - 2023 Krzysztof Gabis
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 substantial 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.
*/
#ifdef _MSC_VER
#ifndef _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS
#endif /* _CRT_SECURE_NO_WARNINGS */
#endif /* _MSC_VER */
#include "parson.h"
#define PARSON_IMPL_VERSION_MAJOR 1
#define PARSON_IMPL_VERSION_MINOR 5
#define PARSON_IMPL_VERSION_PATCH 3
#if (PARSON_VERSION_MAJOR != PARSON_IMPL_VERSION_MAJOR)\
|| (PARSON_VERSION_MINOR != PARSON_IMPL_VERSION_MINOR)\
|| (PARSON_VERSION_PATCH != PARSON_IMPL_VERSION_PATCH)
#error "parson version mismatch between parson.c and parson.h"
#endif
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <errno.h>
/* Apparently sscanf is not implemented in some "standard" libraries, so don't use it, if you
* don't have to. */
#ifdef sscanf
#undef sscanf
#define sscanf THINK_TWICE_ABOUT_USING_SSCANF
#endif
/* strcpy is unsafe */
#ifdef strcpy
#undef strcpy
#endif
#define strcpy USE_MEMCPY_INSTEAD_OF_STRCPY
#define STARTING_CAPACITY 16
#define MAX_NESTING 2048
#ifndef PARSON_DEFAULT_FLOAT_FORMAT
#define PARSON_DEFAULT_FLOAT_FORMAT "%1.17g" /* do not increase precision without incresing NUM_BUF_SIZE */
#endif
#ifndef PARSON_NUM_BUF_SIZE
#define PARSON_NUM_BUF_SIZE 64 /* double printed with "%1.17g" shouldn't be longer than 25 bytes so let's be paranoid and use 64 */
#endif
#ifndef PARSON_INDENT_STR
#define PARSON_INDENT_STR " "
#endif
#define SIZEOF_TOKEN(a) (sizeof(a) - 1)
#define SKIP_CHAR(str) ((*str)++)
#define SKIP_WHITESPACES(str) while (isspace((unsigned char)(**str))) { SKIP_CHAR(str); }
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#undef malloc
#undef free
#if defined(isnan) && defined(isinf)
#define IS_NUMBER_INVALID(x) (isnan((x)) || isinf((x)))
#else
#define IS_NUMBER_INVALID(x) (((x) * 0.0) != 0.0)
#endif
#define OBJECT_INVALID_IX ((size_t)-1)
static JSON_Malloc_Function parson_malloc = malloc;
static JSON_Free_Function parson_free = free;
static int parson_escape_slashes = 1;
static char *parson_float_format = NULL;
static JSON_Number_Serialization_Function parson_number_serialization_function = NULL;
#define IS_CONT(b) (((unsigned char)(b) & 0xC0) == 0x80) /* is utf-8 continuation byte */
typedef int parson_bool_t;
#define PARSON_TRUE 1
#define PARSON_FALSE 0
typedef struct json_string {
char *chars;
size_t length;
} JSON_String;
/* Type definitions */
typedef union json_value_value {
JSON_String string;
double number;
JSON_Object *object;
JSON_Array *array;
int boolean;
int null;
} JSON_Value_Value;
struct json_value_t {
JSON_Value *parent;
JSON_Value_Type type;
JSON_Value_Value value;
};
struct json_object_t {
JSON_Value *wrapping_value;
size_t *cells;
unsigned long *hashes;
char **names;
JSON_Value **values;
size_t *cell_ixs;
size_t count;
size_t item_capacity;
size_t cell_capacity;
};
struct json_array_t {
JSON_Value *wrapping_value;
JSON_Value **items;
size_t count;
size_t capacity;
};
/* Various */
static char * read_file(const char *filename);
static void remove_comments(char *string, const char *start_token, const char *end_token);
static char * parson_strndup(const char *string, size_t n);
static char * parson_strdup(const char *string);
static int parson_sprintf(char * s, const char * format, ...);
static int hex_char_to_int(char c);
static JSON_Status parse_utf16_hex(const char *string, unsigned int *result);
static int num_bytes_in_utf8_sequence(unsigned char c);
static JSON_Status verify_utf8_sequence(const unsigned char *string, int *len);
static parson_bool_t is_valid_utf8(const char *string, size_t string_len);
static parson_bool_t is_decimal(const char *string, size_t length);
static unsigned long hash_string(const char *string, size_t n);
/* JSON Object */
static JSON_Object * json_object_make(JSON_Value *wrapping_value);
static JSON_Status json_object_init(JSON_Object *object, size_t capacity);
static void json_object_deinit(JSON_Object *object, parson_bool_t free_keys, parson_bool_t free_values);
static JSON_Status json_object_grow_and_rehash(JSON_Object *object);
static size_t json_object_get_cell_ix(const JSON_Object *object, const char *key, size_t key_len, unsigned long hash, parson_bool_t *out_found);
static JSON_Status json_object_add(JSON_Object *object, char *name, JSON_Value *value);
static JSON_Value * json_object_getn_value(const JSON_Object *object, const char *name, size_t name_len);
static JSON_Status json_object_remove_internal(JSON_Object *object, const char *name, parson_bool_t free_value);
static JSON_Status json_object_dotremove_internal(JSON_Object *object, const char *name, parson_bool_t free_value);
static void json_object_free(JSON_Object *object);
/* JSON Array */
static JSON_Array * json_array_make(JSON_Value *wrapping_value);
static JSON_Status json_array_add(JSON_Array *array, JSON_Value *value);
static JSON_Status json_array_resize(JSON_Array *array, size_t new_capacity);
static void json_array_free(JSON_Array *array);
/* JSON Value */
static JSON_Value * json_value_init_string_no_copy(char *string, size_t length);
static const JSON_String * json_value_get_string_desc(const JSON_Value *value);
/* Parser */
static JSON_Status skip_quotes(const char **string);
static JSON_Status parse_utf16(const char **unprocessed, char **processed);
static char * process_string(const char *input, size_t input_len, size_t *output_len);
static char * get_quoted_string(const char **string, size_t *output_string_len);
static JSON_Value * parse_object_value(const char **string, size_t nesting);
static JSON_Value * parse_array_value(const char **string, size_t nesting);
static JSON_Value * parse_string_value(const char **string);
static JSON_Value * parse_boolean_value(const char **string);
static JSON_Value * parse_number_value(const char **string);
static JSON_Value * parse_null_value(const char **string);
static JSON_Value * parse_value(const char **string, size_t nesting);
/* Serialization */
static int json_serialize_to_buffer_r(const JSON_Value *value, char *buf, int level, parson_bool_t is_pretty, char *num_buf);
static int json_serialize_string(const char *string, size_t len, char *buf);
/* Various */
static char * read_file(const char * filename) {
FILE *fp = fopen(filename, "r");
size_t size_to_read = 0;
size_t size_read = 0;
long pos;
char *file_contents;
if (!fp) {
return NULL;
}
fseek(fp, 0L, SEEK_END);
pos = ftell(fp);
if (pos < 0) {
fclose(fp);
return NULL;
}
size_to_read = pos;
rewind(fp);
file_contents = (char*)parson_malloc(sizeof(char) * (size_to_read + 1));
if (!file_contents) {
fclose(fp);
return NULL;
}
size_read = fread(file_contents, 1, size_to_read, fp);
if (size_read == 0 || ferror(fp)) {
fclose(fp);
parson_free(file_contents);
return NULL;
}
fclose(fp);
file_contents[size_read] = '\0';
return file_contents;
}
static void remove_comments(char *string, const char *start_token, const char *end_token) {
parson_bool_t in_string = PARSON_FALSE, escaped = PARSON_FALSE;
size_t i;
char *ptr = NULL, current_char;
size_t start_token_len = strlen(start_token);
size_t end_token_len = strlen(end_token);
if (start_token_len == 0 || end_token_len == 0) {
return;
}
while ((current_char = *string) != '\0') {
if (current_char == '\\' && !escaped) {
escaped = PARSON_TRUE;
string++;
continue;
} else if (current_char == '\"' && !escaped) {
in_string = !in_string;
} else if (!in_string && strncmp(string, start_token, start_token_len) == 0) {
for(i = 0; i < start_token_len; i++) {
string[i] = ' ';
}
string = string + start_token_len;
ptr = strstr(string, end_token);
if (!ptr) {
return;
}
for (i = 0; i < (ptr - string) + end_token_len; i++) {
string[i] = ' ';
}
string = ptr + end_token_len - 1;
}
escaped = PARSON_FALSE;
string++;
}
}
static char * parson_strndup(const char *string, size_t n) {
/* We expect the caller has validated that 'n' fits within the input buffer. */
char *output_string = (char*)parson_malloc(n + 1);
if (!output_string) {
return NULL;
}
output_string[n] = '\0';
memcpy(output_string, string, n);
return output_string;
}
static char * parson_strdup(const char *string) {
return parson_strndup(string, strlen(string));
}
static int parson_sprintf(char * s, const char * format, ...) {
int result;
va_list args;
va_start(args, format);
#if defined(__APPLE__) && defined(__clang__)
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
#endif
result = vsprintf(s, format, args);
#if defined(__APPLE__) && defined(__clang__)
#pragma clang diagnostic pop
#endif
va_end(args);
return result;
}
static int hex_char_to_int(char c) {
if (c >= '0' && c <= '9') {
return c - '0';
} else if (c >= 'a' && c <= 'f') {
return c - 'a' + 10;
} else if (c >= 'A' && c <= 'F') {
return c - 'A' + 10;
}
return -1;
}
static JSON_Status parse_utf16_hex(const char *s, unsigned int *result) {
int x1, x2, x3, x4;
if (s[0] == '\0' || s[1] == '\0' || s[2] == '\0' || s[3] == '\0') {
return JSONFailure;
}
x1 = hex_char_to_int(s[0]);
x2 = hex_char_to_int(s[1]);
x3 = hex_char_to_int(s[2]);
x4 = hex_char_to_int(s[3]);
if (x1 == -1 || x2 == -1 || x3 == -1 || x4 == -1) {
return JSONFailure;
}
*result = (unsigned int)((x1 << 12) | (x2 << 8) | (x3 << 4) | x4);
return JSONSuccess;
}
static int num_bytes_in_utf8_sequence(unsigned char c) {
if (c == 0xC0 || c == 0xC1 || c > 0xF4 || IS_CONT(c)) {
return 0;
} else if ((c & 0x80) == 0) { /* 0xxxxxxx */
return 1;
} else if ((c & 0xE0) == 0xC0) { /* 110xxxxx */
return 2;
} else if ((c & 0xF0) == 0xE0) { /* 1110xxxx */
return 3;
} else if ((c & 0xF8) == 0xF0) { /* 11110xxx */
return 4;
}
return 0; /* won't happen */
}
static JSON_Status verify_utf8_sequence(const unsigned char *string, int *len) {
unsigned int cp = 0;
*len = num_bytes_in_utf8_sequence(string[0]);
if (*len == 1) {
cp = string[0];
} else if (*len == 2 && IS_CONT(string[1])) {
cp = string[0] & 0x1F;
cp = (cp << 6) | (string[1] & 0x3F);
} else if (*len == 3 && IS_CONT(string[1]) && IS_CONT(string[2])) {
cp = ((unsigned char)string[0]) & 0xF;
cp = (cp << 6) | (string[1] & 0x3F);
cp = (cp << 6) | (string[2] & 0x3F);
} else if (*len == 4 && IS_CONT(string[1]) && IS_CONT(string[2]) && IS_CONT(string[3])) {
cp = string[0] & 0x7;
cp = (cp << 6) | (string[1] & 0x3F);
cp = (cp << 6) | (string[2] & 0x3F);
cp = (cp << 6) | (string[3] & 0x3F);
} else {
return JSONFailure;
}
/* overlong encodings */
if ((cp < 0x80 && *len > 1) ||
(cp < 0x800 && *len > 2) ||
(cp < 0x10000 && *len > 3)) {
return JSONFailure;
}
/* invalid unicode */
if (cp > 0x10FFFF) {
return JSONFailure;
}
/* surrogate halves */
if (cp >= 0xD800 && cp <= 0xDFFF) {
return JSONFailure;
}
return JSONSuccess;
}
static int is_valid_utf8(const char *string, size_t string_len) {
int len = 0;
const char *string_end = string + string_len;
while (string < string_end) {
if (verify_utf8_sequence((const unsigned char*)string, &len) != JSONSuccess) {
return PARSON_FALSE;
}
string += len;
}
return PARSON_TRUE;
}
static parson_bool_t is_decimal(const char *string, size_t length) {
if (length > 1 && string[0] == '0' && string[1] != '.') {
return PARSON_FALSE;
}
if (length > 2 && !strncmp(string, "-0", 2) && string[2] != '.') {
return PARSON_FALSE;
}
while (length--) {
if (strchr("xX", string[length])) {
return PARSON_FALSE;
}
}
return PARSON_TRUE;
}
static unsigned long hash_string(const char *string, size_t n) {
#ifdef PARSON_FORCE_HASH_COLLISIONS
(void)string;
(void)n;
return 0;
#else
unsigned long hash = 5381;
unsigned char c;
size_t i = 0;
for (i = 0; i < n; i++) {
c = string[i];
if (c == '\0') {
break;
}
hash = ((hash << 5) + hash) + c; /* hash * 33 + c */
}
return hash;
#endif
}
/* JSON Object */
static JSON_Object * json_object_make(JSON_Value *wrapping_value) {
JSON_Status res = JSONFailure;
JSON_Object *new_obj = (JSON_Object*)parson_malloc(sizeof(JSON_Object));
if (new_obj == NULL) {
return NULL;
}
new_obj->wrapping_value = wrapping_value;
res = json_object_init(new_obj, 0);
if (res != JSONSuccess) {
parson_free(new_obj);
return NULL;
}
return new_obj;
}
static JSON_Status json_object_init(JSON_Object *object, size_t capacity) {
unsigned int i = 0;
object->cells = NULL;
object->names = NULL;
object->values = NULL;
object->cell_ixs = NULL;
object->hashes = NULL;
object->count = 0;
object->cell_capacity = capacity;
object->item_capacity = (unsigned int)(capacity * 7/10);
if (capacity == 0) {
return JSONSuccess;
}
object->cells = (size_t*)parson_malloc(object->cell_capacity * sizeof(*object->cells));
object->names = (char**)parson_malloc(object->item_capacity * sizeof(*object->names));
object->values = (JSON_Value**)parson_malloc(object->item_capacity * sizeof(*object->values));
object->cell_ixs = (size_t*)parson_malloc(object->item_capacity * sizeof(*object->cell_ixs));
object->hashes = (unsigned long*)parson_malloc(object->item_capacity * sizeof(*object->hashes));
if (object->cells == NULL
|| object->names == NULL
|| object->values == NULL
|| object->cell_ixs == NULL
|| object->hashes == NULL) {
goto error;
}
for (i = 0; i < object->cell_capacity; i++) {
object->cells[i] = OBJECT_INVALID_IX;
}
return JSONSuccess;
error:
parson_free(object->cells);
parson_free(object->names);
parson_free(object->values);
parson_free(object->cell_ixs);
parson_free(object->hashes);
return JSONFailure;
}
static void json_object_deinit(JSON_Object *object, parson_bool_t free_keys, parson_bool_t free_values) {
unsigned int i = 0;
for (i = 0; i < object->count; i++) {
if (free_keys) {
parson_free(object->names[i]);
}
if (free_values) {
json_value_free(object->values[i]);
}
}
object->count = 0;
object->item_capacity = 0;
object->cell_capacity = 0;
parson_free(object->cells);
parson_free(object->names);
parson_free(object->values);
parson_free(object->cell_ixs);
parson_free(object->hashes);
object->cells = NULL;
object->names = NULL;
object->values = NULL;
object->cell_ixs = NULL;
object->hashes = NULL;
}
static JSON_Status json_object_grow_and_rehash(JSON_Object *object) {
JSON_Value *wrapping_value = NULL;
JSON_Object new_object;
char *key = NULL;
JSON_Value *value = NULL;
unsigned int i = 0;
size_t new_capacity = MAX(object->cell_capacity * 2, STARTING_CAPACITY);
JSON_Status res = json_object_init(&new_object, new_capacity);
if (res != JSONSuccess) {
return JSONFailure;
}
wrapping_value = json_object_get_wrapping_value(object);
new_object.wrapping_value = wrapping_value;
for (i = 0; i < object->count; i++) {
key = object->names[i];
value = object->values[i];
res = json_object_add(&new_object, key, value);
if (res != JSONSuccess) {
json_object_deinit(&new_object, PARSON_FALSE, PARSON_FALSE);
return JSONFailure;
}
value->parent = wrapping_value;
}
json_object_deinit(object, PARSON_FALSE, PARSON_FALSE);
*object = new_object;
return JSONSuccess;
}
static size_t json_object_get_cell_ix(const JSON_Object *object, const char *key, size_t key_len, unsigned long hash, parson_bool_t *out_found) {
size_t cell_ix = hash & (object->cell_capacity - 1);
size_t cell = 0;
size_t ix = 0;
unsigned int i = 0;
unsigned long hash_to_check = 0;
const char *key_to_check = NULL;
size_t key_to_check_len = 0;
*out_found = PARSON_FALSE;
for (i = 0; i < object->cell_capacity; i++) {
ix = (cell_ix + i) & (object->cell_capacity - 1);
cell = object->cells[ix];
if (cell == OBJECT_INVALID_IX) {
return ix;
}
hash_to_check = object->hashes[cell];
if (hash != hash_to_check) {
continue;
}
key_to_check = object->names[cell];
key_to_check_len = strlen(key_to_check);
if (key_to_check_len == key_len && strncmp(key, key_to_check, key_len) == 0) {
*out_found = PARSON_TRUE;
return ix;
}
}
return OBJECT_INVALID_IX;
}
static JSON_Status json_object_add(JSON_Object *object, char *name, JSON_Value *value) {
unsigned long hash = 0;
parson_bool_t found = PARSON_FALSE;
size_t cell_ix = 0;
JSON_Status res = JSONFailure;
if (!object || !name || !value) {
return JSONFailure;
}
hash = hash_string(name, strlen(name));
found = PARSON_FALSE;
cell_ix = json_object_get_cell_ix(object, name, strlen(name), hash, &found);
if (found) {
return JSONFailure;
}
if (object->count >= object->item_capacity) {
res = json_object_grow_and_rehash(object);
if (res != JSONSuccess) {
return JSONFailure;
}
cell_ix = json_object_get_cell_ix(object, name, strlen(name), hash, &found);
}
object->names[object->count] = name;
object->cells[cell_ix] = object->count;
object->values[object->count] = value;
object->cell_ixs[object->count] = cell_ix;
object->hashes[object->count] = hash;
object->count++;
value->parent = json_object_get_wrapping_value(object);
return JSONSuccess;
}
static JSON_Value * json_object_getn_value(const JSON_Object *object, const char *name, size_t name_len) {
unsigned long hash = 0;
parson_bool_t found = PARSON_FALSE;
size_t cell_ix = 0;
size_t item_ix = 0;
if (!object || !name) {
return NULL;
}
hash = hash_string(name, name_len);
found = PARSON_FALSE;
cell_ix = json_object_get_cell_ix(object, name, name_len, hash, &found);
if (!found) {
return NULL;
}
item_ix = object->cells[cell_ix];
return object->values[item_ix];
}
static JSON_Status json_object_remove_internal(JSON_Object *object, const char *name, parson_bool_t free_value) {
unsigned long hash = 0;
parson_bool_t found = PARSON_FALSE;
size_t cell = 0;
size_t item_ix = 0;
size_t last_item_ix = 0;
size_t i = 0;
size_t j = 0;
size_t x = 0;
size_t k = 0;
JSON_Value *val = NULL;
if (object == NULL) {
return JSONFailure;
}
hash = hash_string(name, strlen(name));
found = PARSON_FALSE;
cell = json_object_get_cell_ix(object, name, strlen(name), hash, &found);
if (!found) {
return JSONFailure;
}
item_ix = object->cells[cell];
if (free_value) {
val = object->values[item_ix];
json_value_free(val);
val = NULL;
}
parson_free(object->names[item_ix]);
last_item_ix = object->count - 1;
if (item_ix < last_item_ix) {
object->names[item_ix] = object->names[last_item_ix];
object->values[item_ix] = object->values[last_item_ix];
object->cell_ixs[item_ix] = object->cell_ixs[last_item_ix];
object->hashes[item_ix] = object->hashes[last_item_ix];
object->cells[object->cell_ixs[item_ix]] = item_ix;
}
object->count--;
i = cell;
j = i;
for (x = 0; x < (object->cell_capacity - 1); x++) {
j = (j + 1) & (object->cell_capacity - 1);
if (object->cells[j] == OBJECT_INVALID_IX) {
break;
}
k = object->hashes[object->cells[j]] & (object->cell_capacity - 1);
if ((j > i && (k <= i || k > j))
|| (j < i && (k <= i && k > j))) {
object->cell_ixs[object->cells[j]] = i;
object->cells[i] = object->cells[j];
i = j;
}
}
object->cells[i] = OBJECT_INVALID_IX;
return JSONSuccess;
}
static JSON_Status json_object_dotremove_internal(JSON_Object *object, const char *name, parson_bool_t free_value) {
JSON_Value *temp_value = NULL;
JSON_Object *temp_object = NULL;
const char *dot_pos = strchr(name, '.');
if (!dot_pos) {
return json_object_remove_internal(object, name, free_value);
}
temp_value = json_object_getn_value(object, name, dot_pos - name);
if (json_value_get_type(temp_value) != JSONObject) {
return JSONFailure;
}
temp_object = json_value_get_object(temp_value);
return json_object_dotremove_internal(temp_object, dot_pos + 1, free_value);
}
static void json_object_free(JSON_Object *object) {
json_object_deinit(object, PARSON_TRUE, PARSON_TRUE);
parson_free(object);
}
/* JSON Array */
static JSON_Array * json_array_make(JSON_Value *wrapping_value) {
JSON_Array *new_array = (JSON_Array*)parson_malloc(sizeof(JSON_Array));
if (new_array == NULL) {
return NULL;
}
new_array->wrapping_value = wrapping_value;
new_array->items = (JSON_Value**)NULL;
new_array->capacity = 0;
new_array->count = 0;
return new_array;
}
static JSON_Status json_array_add(JSON_Array *array, JSON_Value *value) {
if (array->count >= array->capacity) {
size_t new_capacity = MAX(array->capacity * 2, STARTING_CAPACITY);
if (json_array_resize(array, new_capacity) != JSONSuccess) {
return JSONFailure;
}
}
value->parent = json_array_get_wrapping_value(array);
array->items[array->count] = value;
array->count++;
return JSONSuccess;
}
static JSON_Status json_array_resize(JSON_Array *array, size_t new_capacity) {
JSON_Value **new_items = NULL;
if (new_capacity == 0) {
return JSONFailure;
}
new_items = (JSON_Value**)parson_malloc(new_capacity * sizeof(JSON_Value*));
if (new_items == NULL) {
return JSONFailure;
}
if (array->items != NULL && array->count > 0) {
memcpy(new_items, array->items, array->count * sizeof(JSON_Value*));
}
parson_free(array->items);
array->items = new_items;
array->capacity = new_capacity;
return JSONSuccess;
}
static void json_array_free(JSON_Array *array) {
size_t i;
for (i = 0; i < array->count; i++) {
json_value_free(array->items[i]);
}
parson_free(array->items);
parson_free(array);
}
/* JSON Value */
static JSON_Value * json_value_init_string_no_copy(char *string, size_t length) {
JSON_Value *new_value = (JSON_Value*)parson_malloc(sizeof(JSON_Value));
if (!new_value) {
return NULL;
}
new_value->parent = NULL;
new_value->type = JSONString;
new_value->value.string.chars = string;
new_value->value.string.length = length;
return new_value;
}
/* Parser */
static JSON_Status skip_quotes(const char **string) {
if (**string != '\"') {
return JSONFailure;
}
SKIP_CHAR(string);
while (**string != '\"') {
if (**string == '\0') {
return JSONFailure;
} else if (**string == '\\') {
SKIP_CHAR(string);
if (**string == '\0') {
return JSONFailure;
}
}
SKIP_CHAR(string);
}
SKIP_CHAR(string);
return JSONSuccess;
}
static JSON_Status parse_utf16(const char **unprocessed, char **processed) {
unsigned int cp, lead, trail;
char *processed_ptr = *processed;
const char *unprocessed_ptr = *unprocessed;
JSON_Status status = JSONFailure;
unprocessed_ptr++; /* skips u */
status = parse_utf16_hex(unprocessed_ptr, &cp);
if (status != JSONSuccess) {
return JSONFailure;
}
if (cp < 0x80) {
processed_ptr[0] = (char)cp; /* 0xxxxxxx */
} else if (cp < 0x800) {
processed_ptr[0] = ((cp >> 6) & 0x1F) | 0xC0; /* 110xxxxx */
processed_ptr[1] = ((cp) & 0x3F) | 0x80; /* 10xxxxxx */
processed_ptr += 1;
} else if (cp < 0xD800 || cp > 0xDFFF) {
processed_ptr[0] = ((cp >> 12) & 0x0F) | 0xE0; /* 1110xxxx */
processed_ptr[1] = ((cp >> 6) & 0x3F) | 0x80; /* 10xxxxxx */
processed_ptr[2] = ((cp) & 0x3F) | 0x80; /* 10xxxxxx */
processed_ptr += 2;
} else if (cp >= 0xD800 && cp <= 0xDBFF) { /* lead surrogate (0xD800..0xDBFF) */
lead = cp;
unprocessed_ptr += 4; /* should always be within the buffer, otherwise previous sscanf would fail */
if (*unprocessed_ptr++ != '\\' || *unprocessed_ptr++ != 'u') {
return JSONFailure;
}
status = parse_utf16_hex(unprocessed_ptr, &trail);
if (status != JSONSuccess || trail < 0xDC00 || trail > 0xDFFF) { /* valid trail surrogate? (0xDC00..0xDFFF) */
return JSONFailure;
}
cp = ((((lead - 0xD800) & 0x3FF) << 10) | ((trail - 0xDC00) & 0x3FF)) + 0x010000;
processed_ptr[0] = (((cp >> 18) & 0x07) | 0xF0); /* 11110xxx */
processed_ptr[1] = (((cp >> 12) & 0x3F) | 0x80); /* 10xxxxxx */
processed_ptr[2] = (((cp >> 6) & 0x3F) | 0x80); /* 10xxxxxx */
processed_ptr[3] = (((cp) & 0x3F) | 0x80); /* 10xxxxxx */
processed_ptr += 3;
} else { /* trail surrogate before lead surrogate */
return JSONFailure;
}
unprocessed_ptr += 3;
*processed = processed_ptr;
*unprocessed = unprocessed_ptr;
return JSONSuccess;
}
/* Copies and processes passed string up to supplied length.
Example: "\u006Corem ipsum" -> lorem ipsum */
static char* process_string(const char *input, size_t input_len, size_t *output_len) {
const char *input_ptr = input;
size_t initial_size = (input_len + 1) * sizeof(char);
size_t final_size = 0;
char *output = NULL, *output_ptr = NULL, *resized_output = NULL;
output = (char*)parson_malloc(initial_size);
if (output == NULL) {
goto error;
}
output_ptr = output;
while ((*input_ptr != '\0') && (size_t)(input_ptr - input) < input_len) {
if (*input_ptr == '\\') {
input_ptr++;
switch (*input_ptr) {
case '\"': *output_ptr = '\"'; break;
case '\\': *output_ptr = '\\'; break;
case '/': *output_ptr = '/'; break;
case 'b': *output_ptr = '\b'; break;
case 'f': *output_ptr = '\f'; break;
case 'n': *output_ptr = '\n'; break;
case 'r': *output_ptr = '\r'; break;
case 't': *output_ptr = '\t'; break;
case 'u':
if (parse_utf16(&input_ptr, &output_ptr) != JSONSuccess) {
goto error;
}
break;
default:
goto error;
}
} else if ((unsigned char)*input_ptr < 0x20) {
goto error; /* 0x00-0x19 are invalid characters for json string (http://www.ietf.org/rfc/rfc4627.txt) */
} else {
*output_ptr = *input_ptr;
}
output_ptr++;
input_ptr++;
}
*output_ptr = '\0';
/* resize to new length */
final_size = (size_t)(output_ptr-output) + 1;
/* todo: don't resize if final_size == initial_size */
resized_output = (char*)parson_malloc(final_size);
if (resized_output == NULL) {
goto error;
}
memcpy(resized_output, output, final_size);
*output_len = final_size - 1;
parson_free(output);
return resized_output;
error:
parson_free(output);
return NULL;
}
/* Return processed contents of a string between quotes and
skips passed argument to a matching quote. */
static char * get_quoted_string(const char **string, size_t *output_string_len) {
const char *string_start = *string;
size_t input_string_len = 0;
JSON_Status status = skip_quotes(string);
if (status != JSONSuccess) {
return NULL;
}
input_string_len = *string - string_start - 2; /* length without quotes */
return process_string(string_start + 1, input_string_len, output_string_len);
}
static JSON_Value * parse_value(const char **string, size_t nesting) {
if (nesting > MAX_NESTING) {
return NULL;
}
SKIP_WHITESPACES(string);
switch (**string) {
case '{':
return parse_object_value(string, nesting + 1);
case '[':
return parse_array_value(string, nesting + 1);
case '\"':
return parse_string_value(string);
case 'f': case 't':
return parse_boolean_value(string);
case '-':
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
return parse_number_value(string);
case 'n':
return parse_null_value(string);
default:
return NULL;
}
}
static JSON_Value * parse_object_value(const char **string, size_t nesting) {
JSON_Status status = JSONFailure;
JSON_Value *output_value = NULL, *new_value = NULL;
JSON_Object *output_object = NULL;
char *new_key = NULL;
output_value = json_value_init_object();
if (output_value == NULL) {
return NULL;
}
if (**string != '{') {
json_value_free(output_value);
return NULL;
}
output_object = json_value_get_object(output_value);
SKIP_CHAR(string);
SKIP_WHITESPACES(string);
if (**string == '}') { /* empty object */
SKIP_CHAR(string);
return output_value;
}
while (**string != '\0') {
size_t key_len = 0;
new_key = get_quoted_string(string, &key_len);
/* We do not support key names with embedded \0 chars */
if (!new_key) {
json_value_free(output_value);
return NULL;
}
if (key_len != strlen(new_key)) {
parson_free(new_key);
json_value_free(output_value);
return NULL;
}
SKIP_WHITESPACES(string);
if (**string != ':') {
parson_free(new_key);
json_value_free(output_value);
return NULL;
}
SKIP_CHAR(string);
new_value = parse_value(string, nesting);
if (new_value == NULL) {
parson_free(new_key);
json_value_free(output_value);
return NULL;
}
status = json_object_add(output_object, new_key, new_value);
if (status != JSONSuccess) {
parson_free(new_key);
json_value_free(new_value);
json_value_free(output_value);
return NULL;
}
SKIP_WHITESPACES(string);
if (**string != ',') {
break;
}
SKIP_CHAR(string);
SKIP_WHITESPACES(string);
if (**string == '}') {
break;
}
}
SKIP_WHITESPACES(string);
if (**string != '}') {
json_value_free(output_value);
return NULL;
}
SKIP_CHAR(string);
return output_value;
}
static JSON_Value * parse_array_value(const char **string, size_t nesting) {
JSON_Value *output_value = NULL, *new_array_value = NULL;
JSON_Array *output_array = NULL;
output_value = json_value_init_array();
if (output_value == NULL) {
return NULL;
}
if (**string != '[') {
json_value_free(output_value);
return NULL;
}
output_array = json_value_get_array(output_value);
SKIP_CHAR(string);
SKIP_WHITESPACES(string);
if (**string == ']') { /* empty array */
SKIP_CHAR(string);
return output_value;
}
while (**string != '\0') {
new_array_value = parse_value(string, nesting);
if (new_array_value == NULL) {
json_value_free(output_value);
return NULL;
}
if (json_array_add(output_array, new_array_value) != JSONSuccess) {
json_value_free(new_array_value);
json_value_free(output_value);
return NULL;
}
SKIP_WHITESPACES(string);
if (**string != ',') {
break;
}
SKIP_CHAR(string);
SKIP_WHITESPACES(string);
if (**string == ']') {
break;
}
}
SKIP_WHITESPACES(string);
if (**string != ']' || /* Trim array after parsing is over */
json_array_resize(output_array, json_array_get_count(output_array)) != JSONSuccess) {
json_value_free(output_value);
return NULL;
}
SKIP_CHAR(string);
return output_value;
}
static JSON_Value * parse_string_value(const char **string) {
JSON_Value *value = NULL;
size_t new_string_len = 0;
char *new_string = get_quoted_string(string, &new_string_len);
if (new_string == NULL) {
return NULL;
}
value = json_value_init_string_no_copy(new_string, new_string_len);
if (value == NULL) {
parson_free(new_string);
return NULL;
}
return value;
}
static JSON_Value * parse_boolean_value(const char **string) {
size_t true_token_size = SIZEOF_TOKEN("true");
size_t false_token_size = SIZEOF_TOKEN("false");
if (strncmp("true", *string, true_token_size) == 0) {
*string += true_token_size;
return json_value_init_boolean(1);
} else if (strncmp("false", *string, false_token_size) == 0) {
*string += false_token_size;
return json_value_init_boolean(0);
}
return NULL;
}
static JSON_Value * parse_number_value(const char **string) {
char *end;
double number = 0;
errno = 0;
number = strtod(*string, &end);
if (errno == ERANGE && (number <= -HUGE_VAL || number >= HUGE_VAL)) {
return NULL;
}
if ((errno && errno != ERANGE) || !is_decimal(*string, end - *string)) {
return NULL;
}
*string = end;
return json_value_init_number(number);
}
static JSON_Value * parse_null_value(const char **string) {
size_t token_size = SIZEOF_TOKEN("null");
if (strncmp("null", *string, token_size) == 0) {
*string += token_size;
return json_value_init_null();
}
return NULL;
}
/* Serialization */
/* APPEND_STRING() is only called on string literals.
It's a bit hacky because it makes plenty of assumptions about the external state
and should eventually be tidied up into a function (same goes for APPEND_INDENT)
*/
#define APPEND_STRING(str) do {\
written = SIZEOF_TOKEN((str));\
if (buf != NULL) {\
memcpy(buf, (str), written);\
buf[written] = '\0';\
buf += written;\
}\
written_total += written;\
} while (0)
#define APPEND_INDENT(level) do {\
int level_i = 0;\
for (level_i = 0; level_i < (level); level_i++) {\
APPEND_STRING(PARSON_INDENT_STR);\
}\
} while (0)
static int json_serialize_to_buffer_r(const JSON_Value *value, char *buf, int level, parson_bool_t is_pretty, char *num_buf)
{
const char *key = NULL, *string = NULL;
JSON_Value *temp_value = NULL;
JSON_Array *array = NULL;
JSON_Object *object = NULL;
size_t i = 0, count = 0;
double num = 0.0;
int written = -1, written_total = 0;
size_t len = 0;
switch (json_value_get_type(value)) {
case JSONArray:
array = json_value_get_array(value);
count = json_array_get_count(array);
APPEND_STRING("[");
if (count > 0 && is_pretty) {
APPEND_STRING("\n");
}
for (i = 0; i < count; i++) {
if (is_pretty) {
APPEND_INDENT(level+1);
}
temp_value = json_array_get_value(array, i);
written = json_serialize_to_buffer_r(temp_value, buf, level+1, is_pretty, num_buf);
if (written < 0) {
return -1;
}
if (buf != NULL) {
buf += written;
}
written_total += written;
if (i < (count - 1)) {
APPEND_STRING(",");
}
if (is_pretty) {
APPEND_STRING("\n");
}
}
if (count > 0 && is_pretty) {
APPEND_INDENT(level);
}
APPEND_STRING("]");
return written_total;
case JSONObject:
object = json_value_get_object(value);
count = json_object_get_count(object);
APPEND_STRING("{");
if (count > 0 && is_pretty) {
APPEND_STRING("\n");
}
for (i = 0; i < count; i++) {
key = json_object_get_name(object, i);
if (key == NULL) {
return -1;
}
if (is_pretty) {
APPEND_INDENT(level+1);
}
/* We do not support key names with embedded \0 chars */
written = json_serialize_string(key, strlen(key), buf);
if (written < 0) {
return -1;
}
if (buf != NULL) {
buf += written;
}
written_total += written;
APPEND_STRING(":");
if (is_pretty) {
APPEND_STRING(" ");
}
temp_value = json_object_get_value_at(object, i);
written = json_serialize_to_buffer_r(temp_value, buf, level+1, is_pretty, num_buf);
if (written < 0) {
return -1;
}
if (buf != NULL) {
buf += written;
}
written_total += written;
if (i < (count - 1)) {
APPEND_STRING(",");
}
if (is_pretty) {
APPEND_STRING("\n");
}
}
if (count > 0 && is_pretty) {
APPEND_INDENT(level);
}
APPEND_STRING("}");
return written_total;
case JSONString:
string = json_value_get_string(value);
if (string == NULL) {
return -1;
}
len = json_value_get_string_len(value);
written = json_serialize_string(string, len, buf);
if (written < 0) {
return -1;
}
if (buf != NULL) {
buf += written;
}
written_total += written;
return written_total;
case JSONBoolean:
if (json_value_get_boolean(value)) {
APPEND_STRING("true");
} else {
APPEND_STRING("false");
}
return written_total;
case JSONNumber:
num = json_value_get_number(value);
if (buf != NULL) {
num_buf = buf;
}
if (parson_number_serialization_function) {
written = parson_number_serialization_function(num, num_buf);
} else {
const char *float_format = parson_float_format ? parson_float_format : PARSON_DEFAULT_FLOAT_FORMAT;
written = parson_sprintf(num_buf, float_format, num);
}
if (written < 0) {
return -1;
}
if (buf != NULL) {
buf += written;
}
written_total += written;
return written_total;
case JSONNull:
APPEND_STRING("null");
return written_total;
case JSONError:
return -1;
default:
return -1;
}
}
static int json_serialize_string(const char *string, size_t len, char *buf) {
size_t i = 0;
char c = '\0';
int written = -1, written_total = 0;
APPEND_STRING("\"");
for (i = 0; i < len; i++) {
c = string[i];
switch (c) {
case '\"': APPEND_STRING("\\\""); break;
case '\\': APPEND_STRING("\\\\"); break;
case '\b': APPEND_STRING("\\b"); break;
case '\f': APPEND_STRING("\\f"); break;
case '\n': APPEND_STRING("\\n"); break;
case '\r': APPEND_STRING("\\r"); break;
case '\t': APPEND_STRING("\\t"); break;
case '\x00': APPEND_STRING("\\u0000"); break;
case '\x01': APPEND_STRING("\\u0001"); break;
case '\x02': APPEND_STRING("\\u0002"); break;
case '\x03': APPEND_STRING("\\u0003"); break;
case '\x04': APPEND_STRING("\\u0004"); break;
case '\x05': APPEND_STRING("\\u0005"); break;
case '\x06': APPEND_STRING("\\u0006"); break;
case '\x07': APPEND_STRING("\\u0007"); break;
/* '\x08' duplicate: '\b' */
/* '\x09' duplicate: '\t' */
/* '\x0a' duplicate: '\n' */
case '\x0b': APPEND_STRING("\\u000b"); break;
/* '\x0c' duplicate: '\f' */
/* '\x0d' duplicate: '\r' */
case '\x0e': APPEND_STRING("\\u000e"); break;
case '\x0f': APPEND_STRING("\\u000f"); break;
case '\x10': APPEND_STRING("\\u0010"); break;
case '\x11': APPEND_STRING("\\u0011"); break;
case '\x12': APPEND_STRING("\\u0012"); break;
case '\x13': APPEND_STRING("\\u0013"); break;
case '\x14': APPEND_STRING("\\u0014"); break;
case '\x15': APPEND_STRING("\\u0015"); break;
case '\x16': APPEND_STRING("\\u0016"); break;
case '\x17': APPEND_STRING("\\u0017"); break;
case '\x18': APPEND_STRING("\\u0018"); break;
case '\x19': APPEND_STRING("\\u0019"); break;
case '\x1a': APPEND_STRING("\\u001a"); break;
case '\x1b': APPEND_STRING("\\u001b"); break;
case '\x1c': APPEND_STRING("\\u001c"); break;
case '\x1d': APPEND_STRING("\\u001d"); break;
case '\x1e': APPEND_STRING("\\u001e"); break;
case '\x1f': APPEND_STRING("\\u001f"); break;
case '/':
if (parson_escape_slashes) {
APPEND_STRING("\\/"); /* to make json embeddable in xml\/html */
} else {
APPEND_STRING("/");
}
break;
default:
if (buf != NULL) {
buf[0] = c;
buf += 1;
}
written_total += 1;
break;
}
}
APPEND_STRING("\"");
return written_total;
}
#undef APPEND_STRING
#undef APPEND_INDENT
/* Parser API */
JSON_Value * json_parse_file(const char *filename) {
char *file_contents = read_file(filename);
JSON_Value *output_value = NULL;
if (file_contents == NULL) {
return NULL;
}
output_value = json_parse_string(file_contents);
parson_free(file_contents);
return output_value;
}
JSON_Value * json_parse_file_with_comments(const char *filename) {
char *file_contents = read_file(filename);
JSON_Value *output_value = NULL;
if (file_contents == NULL) {
return NULL;
}
output_value = json_parse_string_with_comments(file_contents);
parson_free(file_contents);
return output_value;
}
JSON_Value * json_parse_string(const char *string) {
if (string == NULL) {
return NULL;
}
if (string[0] == '\xEF' && string[1] == '\xBB' && string[2] == '\xBF') {
string = string + 3; /* Support for UTF-8 BOM */
}
return parse_value((const char**)&string, 0);
}
JSON_Value * json_parse_string_with_comments(const char *string) {
JSON_Value *result = NULL;
char *string_mutable_copy = NULL, *string_mutable_copy_ptr = NULL;
string_mutable_copy = parson_strdup(string);
if (string_mutable_copy == NULL) {
return NULL;
}
remove_comments(string_mutable_copy, "/*", "*/");
remove_comments(string_mutable_copy, "//", "\n");
string_mutable_copy_ptr = string_mutable_copy;
result = parse_value((const char**)&string_mutable_copy_ptr, 0);
parson_free(string_mutable_copy);
return result;
}
/* JSON Object API */
JSON_Value * json_object_get_value(const JSON_Object *object, const char *name) {
if (object == NULL || name == NULL) {
return NULL;
}
return json_object_getn_value(object, name, strlen(name));
}
const char * json_object_get_string(const JSON_Object *object, const char *name) {
return json_value_get_string(json_object_get_value(object, name));
}
size_t json_object_get_string_len(const JSON_Object *object, const char *name) {
return json_value_get_string_len(json_object_get_value(object, name));
}
double json_object_get_number(const JSON_Object *object, const char *name) {
return json_value_get_number(json_object_get_value(object, name));
}
JSON_Object * json_object_get_object(const JSON_Object *object, const char *name) {
return json_value_get_object(json_object_get_value(object, name));
}
JSON_Array * json_object_get_array(const JSON_Object *object, const char *name) {
return json_value_get_array(json_object_get_value(object, name));
}
int json_object_get_boolean(const JSON_Object *object, const char *name) {
return json_value_get_boolean(json_object_get_value(object, name));
}
JSON_Value * json_object_dotget_value(const JSON_Object *object, const char *name) {
const char *dot_position = strchr(name, '.');
if (!dot_position) {
return json_object_get_value(object, name);
}
object = json_value_get_object(json_object_getn_value(object, name, dot_position - name));
return json_object_dotget_value(object, dot_position + 1);
}
const char * json_object_dotget_string(const JSON_Object *object, const char *name) {
return json_value_get_string(json_object_dotget_value(object, name));
}
size_t json_object_dotget_string_len(const JSON_Object *object, const char *name) {
return json_value_get_string_len(json_object_dotget_value(object, name));
}
double json_object_dotget_number(const JSON_Object *object, const char *name) {
return json_value_get_number(json_object_dotget_value(object, name));
}
JSON_Object * json_object_dotget_object(const JSON_Object *object, const char *name) {
return json_value_get_object(json_object_dotget_value(object, name));
}
JSON_Array * json_object_dotget_array(const JSON_Object *object, const char *name) {
return json_value_get_array(json_object_dotget_value(object, name));
}
int json_object_dotget_boolean(const JSON_Object *object, const char *name) {
return json_value_get_boolean(json_object_dotget_value(object, name));
}
size_t json_object_get_count(const JSON_Object *object) {
return object ? object->count : 0;
}
const char * json_object_get_name(const JSON_Object *object, size_t index) {
if (object == NULL || index >= json_object_get_count(object)) {
return NULL;
}
return object->names[index];
}
JSON_Value * json_object_get_value_at(const JSON_Object *object, size_t index) {
if (object == NULL || index >= json_object_get_count(object)) {
return NULL;
}
return object->values[index];
}
JSON_Value *json_object_get_wrapping_value(const JSON_Object *object) {
if (!object) {
return NULL;
}
return object->wrapping_value;
}
int json_object_has_value (const JSON_Object *object, const char *name) {
return json_object_get_value(object, name) != NULL;
}
int json_object_has_value_of_type(const JSON_Object *object, const char *name, JSON_Value_Type type) {
JSON_Value *val = json_object_get_value(object, name);
return val != NULL && json_value_get_type(val) == type;
}
int json_object_dothas_value (const JSON_Object *object, const char *name) {
return json_object_dotget_value(object, name) != NULL;
}
int json_object_dothas_value_of_type(const JSON_Object *object, const char *name, JSON_Value_Type type) {
JSON_Value *val = json_object_dotget_value(object, name);
return val != NULL && json_value_get_type(val) == type;
}
/* JSON Array API */
JSON_Value * json_array_get_value(const JSON_Array *array, size_t index) {
if (array == NULL || index >= json_array_get_count(array)) {
return NULL;
}
return array->items[index];
}
const char * json_array_get_string(const JSON_Array *array, size_t index) {
return json_value_get_string(json_array_get_value(array, index));
}
size_t json_array_get_string_len(const JSON_Array *array, size_t index) {
return json_value_get_string_len(json_array_get_value(array, index));
}
double json_array_get_number(const JSON_Array *array, size_t index) {
return json_value_get_number(json_array_get_value(array, index));
}
JSON_Object * json_array_get_object(const JSON_Array *array, size_t index) {
return json_value_get_object(json_array_get_value(array, index));
}
JSON_Array * json_array_get_array(const JSON_Array *array, size_t index) {
return json_value_get_array(json_array_get_value(array, index));
}
int json_array_get_boolean(const JSON_Array *array, size_t index) {
return json_value_get_boolean(json_array_get_value(array, index));
}
size_t json_array_get_count(const JSON_Array *array) {
return array ? array->count : 0;
}
JSON_Value * json_array_get_wrapping_value(const JSON_Array *array) {
if (!array) {
return NULL;
}
return array->wrapping_value;
}
/* JSON Value API */
JSON_Value_Type json_value_get_type(const JSON_Value *value) {
return value ? value->type : JSONError;
}
JSON_Object * json_value_get_object(const JSON_Value *value) {
return json_value_get_type(value) == JSONObject ? value->value.object : NULL;
}
JSON_Array * json_value_get_array(const JSON_Value *value) {
return json_value_get_type(value) == JSONArray ? value->value.array : NULL;
}
static const JSON_String * json_value_get_string_desc(const JSON_Value *value) {
return json_value_get_type(value) == JSONString ? &value->value.string : NULL;
}
const char * json_value_get_string(const JSON_Value *value) {
const JSON_String *str = json_value_get_string_desc(value);
return str ? str->chars : NULL;
}
size_t json_value_get_string_len(const JSON_Value *value) {
const JSON_String *str = json_value_get_string_desc(value);
return str ? str->length : 0;
}
double json_value_get_number(const JSON_Value *value) {
return json_value_get_type(value) == JSONNumber ? value->value.number : 0;
}
int json_value_get_boolean(const JSON_Value *value) {
return json_value_get_type(value) == JSONBoolean ? value->value.boolean : -1;
}
JSON_Value * json_value_get_parent (const JSON_Value *value) {
return value ? value->parent : NULL;
}
void json_value_free(JSON_Value *value) {
switch (json_value_get_type(value)) {
case JSONObject:
json_object_free(value->value.object);
break;
case JSONString:
parson_free(value->value.string.chars);
break;
case JSONArray:
json_array_free(value->value.array);
break;
default:
break;
}
parson_free(value);
}
JSON_Value * json_value_init_object(void) {
JSON_Value *new_value = (JSON_Value*)parson_malloc(sizeof(JSON_Value));
if (!new_value) {
return NULL;
}
new_value->parent = NULL;
new_value->type = JSONObject;
new_value->value.object = json_object_make(new_value);
if (!new_value->value.object) {
parson_free(new_value);
return NULL;
}
return new_value;
}
JSON_Value * json_value_init_array(void) {
JSON_Value *new_value = (JSON_Value*)parson_malloc(sizeof(JSON_Value));
if (!new_value) {
return NULL;
}
new_value->parent = NULL;
new_value->type = JSONArray;
new_value->value.array = json_array_make(new_value);
if (!new_value->value.array) {
parson_free(new_value);
return NULL;
}
return new_value;
}
JSON_Value * json_value_init_string(const char *string) {
if (string == NULL) {
return NULL;
}
return json_value_init_string_with_len(string, strlen(string));
}
JSON_Value * json_value_init_string_with_len(const char *string, size_t length) {
char *copy = NULL;
JSON_Value *value;
if (string == NULL) {
return NULL;
}
if (!is_valid_utf8(string, length)) {
return NULL;
}
copy = parson_strndup(string, length);
if (copy == NULL) {
return NULL;
}
value = json_value_init_string_no_copy(copy, length);
if (value == NULL) {
parson_free(copy);
}
return value;
}
JSON_Value * json_value_init_number(double number) {
JSON_Value *new_value = NULL;
if (IS_NUMBER_INVALID(number)) {
return NULL;
}
new_value = (JSON_Value*)parson_malloc(sizeof(JSON_Value));
if (new_value == NULL) {
return NULL;
}
new_value->parent = NULL;
new_value->type = JSONNumber;
new_value->value.number = number;
return new_value;
}
JSON_Value * json_value_init_boolean(int boolean) {
JSON_Value *new_value = (JSON_Value*)parson_malloc(sizeof(JSON_Value));
if (!new_value) {
return NULL;
}
new_value->parent = NULL;
new_value->type = JSONBoolean;
new_value->value.boolean = boolean ? 1 : 0;
return new_value;
}
JSON_Value * json_value_init_null(void) {
JSON_Value *new_value = (JSON_Value*)parson_malloc(sizeof(JSON_Value));
if (!new_value) {
return NULL;
}
new_value->parent = NULL;
new_value->type = JSONNull;
return new_value;
}
JSON_Value * json_value_deep_copy(const JSON_Value *value) {
size_t i = 0;
JSON_Value *return_value = NULL, *temp_value_copy = NULL, *temp_value = NULL;
const JSON_String *temp_string = NULL;
const char *temp_key = NULL;
char *temp_string_copy = NULL;
JSON_Array *temp_array = NULL, *temp_array_copy = NULL;
JSON_Object *temp_object = NULL, *temp_object_copy = NULL;
JSON_Status res = JSONFailure;
char *key_copy = NULL;
switch (json_value_get_type(value)) {
case JSONArray:
temp_array = json_value_get_array(value);
return_value = json_value_init_array();
if (return_value == NULL) {
return NULL;
}
temp_array_copy = json_value_get_array(return_value);
for (i = 0; i < json_array_get_count(temp_array); i++) {
temp_value = json_array_get_value(temp_array, i);
temp_value_copy = json_value_deep_copy(temp_value);
if (temp_value_copy == NULL) {
json_value_free(return_value);
return NULL;
}
if (json_array_add(temp_array_copy, temp_value_copy) != JSONSuccess) {
json_value_free(return_value);
json_value_free(temp_value_copy);
return NULL;
}
}
return return_value;
case JSONObject:
temp_object = json_value_get_object(value);
return_value = json_value_init_object();
if (!return_value) {
return NULL;
}
temp_object_copy = json_value_get_object(return_value);
for (i = 0; i < json_object_get_count(temp_object); i++) {
temp_key = json_object_get_name(temp_object, i);
temp_value = json_object_get_value(temp_object, temp_key);
temp_value_copy = json_value_deep_copy(temp_value);
if (!temp_value_copy) {
json_value_free(return_value);
return NULL;
}
key_copy = parson_strdup(temp_key);
if (!key_copy) {
json_value_free(temp_value_copy);
json_value_free(return_value);
return NULL;
}
res = json_object_add(temp_object_copy, key_copy, temp_value_copy);
if (res != JSONSuccess) {
parson_free(key_copy);
json_value_free(temp_value_copy);
json_value_free(return_value);
return NULL;
}
}
return return_value;
case JSONBoolean:
return json_value_init_boolean(json_value_get_boolean(value));
case JSONNumber:
return json_value_init_number(json_value_get_number(value));
case JSONString:
temp_string = json_value_get_string_desc(value);
if (temp_string == NULL) {
return NULL;
}
temp_string_copy = parson_strndup(temp_string->chars, temp_string->length);
if (temp_string_copy == NULL) {
return NULL;
}
return_value = json_value_init_string_no_copy(temp_string_copy, temp_string->length);
if (return_value == NULL) {
parson_free(temp_string_copy);
}
return return_value;
case JSONNull:
return json_value_init_null();
case JSONError:
return NULL;
default:
return NULL;
}
}
size_t json_serialization_size(const JSON_Value *value) {
char num_buf[PARSON_NUM_BUF_SIZE]; /* recursively allocating buffer on stack is a bad idea, so let's do it only once */
int res = json_serialize_to_buffer_r(value, NULL, 0, PARSON_FALSE, num_buf);
return res < 0 ? 0 : (size_t)(res) + 1;
}
JSON_Status json_serialize_to_buffer(const JSON_Value *value, char *buf, size_t buf_size_in_bytes) {
int written = -1;
size_t needed_size_in_bytes = json_serialization_size(value);
if (needed_size_in_bytes == 0 || buf_size_in_bytes < needed_size_in_bytes) {
return JSONFailure;
}
written = json_serialize_to_buffer_r(value, buf, 0, PARSON_FALSE, NULL);
if (written < 0) {
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_serialize_to_file(const JSON_Value *value, const char *filename) {
JSON_Status return_code = JSONSuccess;
FILE *fp = NULL;
char *serialized_string = json_serialize_to_string(value);
if (serialized_string == NULL) {
return JSONFailure;
}
fp = fopen(filename, "w");
if (fp == NULL) {
json_free_serialized_string(serialized_string);
return JSONFailure;
}
if (fputs(serialized_string, fp) == EOF) {
return_code = JSONFailure;
}
if (fclose(fp) == EOF) {
return_code = JSONFailure;
}
json_free_serialized_string(serialized_string);
return return_code;
}
char * json_serialize_to_string(const JSON_Value *value) {
JSON_Status serialization_result = JSONFailure;
size_t buf_size_bytes = json_serialization_size(value);
char *buf = NULL;
if (buf_size_bytes == 0) {
return NULL;
}
buf = (char*)parson_malloc(buf_size_bytes);
if (buf == NULL) {
return NULL;
}
serialization_result = json_serialize_to_buffer(value, buf, buf_size_bytes);
if (serialization_result != JSONSuccess) {
json_free_serialized_string(buf);
return NULL;
}
return buf;
}
size_t json_serialization_size_pretty(const JSON_Value *value) {
char num_buf[PARSON_NUM_BUF_SIZE]; /* recursively allocating buffer on stack is a bad idea, so let's do it only once */
int res = json_serialize_to_buffer_r(value, NULL, 0, PARSON_TRUE, num_buf);
return res < 0 ? 0 : (size_t)(res) + 1;
}
JSON_Status json_serialize_to_buffer_pretty(const JSON_Value *value, char *buf, size_t buf_size_in_bytes) {
int written = -1;
size_t needed_size_in_bytes = json_serialization_size_pretty(value);
if (needed_size_in_bytes == 0 || buf_size_in_bytes < needed_size_in_bytes) {
return JSONFailure;
}
written = json_serialize_to_buffer_r(value, buf, 0, PARSON_TRUE, NULL);
if (written < 0) {
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_serialize_to_file_pretty(const JSON_Value *value, const char *filename) {
JSON_Status return_code = JSONSuccess;
FILE *fp = NULL;
char *serialized_string = json_serialize_to_string_pretty(value);
if (serialized_string == NULL) {
return JSONFailure;
}
fp = fopen(filename, "w");
if (fp == NULL) {
json_free_serialized_string(serialized_string);
return JSONFailure;
}
if (fputs(serialized_string, fp) == EOF) {
return_code = JSONFailure;
}
if (fclose(fp) == EOF) {
return_code = JSONFailure;
}
json_free_serialized_string(serialized_string);
return return_code;
}
char * json_serialize_to_string_pretty(const JSON_Value *value) {
JSON_Status serialization_result = JSONFailure;
size_t buf_size_bytes = json_serialization_size_pretty(value);
char *buf = NULL;
if (buf_size_bytes == 0) {
return NULL;
}
buf = (char*)parson_malloc(buf_size_bytes);
if (buf == NULL) {
return NULL;
}
serialization_result = json_serialize_to_buffer_pretty(value, buf, buf_size_bytes);
if (serialization_result != JSONSuccess) {
json_free_serialized_string(buf);
return NULL;
}
return buf;
}
void json_free_serialized_string(char *string) {
parson_free(string);
}
JSON_Status json_array_remove(JSON_Array *array, size_t ix) {
size_t to_move_bytes = 0;
if (array == NULL || ix >= json_array_get_count(array)) {
return JSONFailure;
}
json_value_free(json_array_get_value(array, ix));
to_move_bytes = (json_array_get_count(array) - 1 - ix) * sizeof(JSON_Value*);
memmove(array->items + ix, array->items + ix + 1, to_move_bytes);
array->count -= 1;
return JSONSuccess;
}
JSON_Status json_array_replace_value(JSON_Array *array, size_t ix, JSON_Value *value) {
if (array == NULL || value == NULL || value->parent != NULL || ix >= json_array_get_count(array)) {
return JSONFailure;
}
json_value_free(json_array_get_value(array, ix));
value->parent = json_array_get_wrapping_value(array);
array->items[ix] = value;
return JSONSuccess;
}
JSON_Status json_array_replace_string(JSON_Array *array, size_t i, const char* string) {
JSON_Value *value = json_value_init_string(string);
if (value == NULL) {
return JSONFailure;
}
if (json_array_replace_value(array, i, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_replace_string_with_len(JSON_Array *array, size_t i, const char *string, size_t len) {
JSON_Value *value = json_value_init_string_with_len(string, len);
if (value == NULL) {
return JSONFailure;
}
if (json_array_replace_value(array, i, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_replace_number(JSON_Array *array, size_t i, double number) {
JSON_Value *value = json_value_init_number(number);
if (value == NULL) {
return JSONFailure;
}
if (json_array_replace_value(array, i, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_replace_boolean(JSON_Array *array, size_t i, int boolean) {
JSON_Value *value = json_value_init_boolean(boolean);
if (value == NULL) {
return JSONFailure;
}
if (json_array_replace_value(array, i, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_replace_null(JSON_Array *array, size_t i) {
JSON_Value *value = json_value_init_null();
if (value == NULL) {
return JSONFailure;
}
if (json_array_replace_value(array, i, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_clear(JSON_Array *array) {
size_t i = 0;
if (array == NULL) {
return JSONFailure;
}
for (i = 0; i < json_array_get_count(array); i++) {
json_value_free(json_array_get_value(array, i));
}
array->count = 0;
return JSONSuccess;
}
JSON_Status json_array_append_value(JSON_Array *array, JSON_Value *value) {
if (array == NULL || value == NULL || value->parent != NULL) {
return JSONFailure;
}
return json_array_add(array, value);
}
JSON_Status json_array_append_string(JSON_Array *array, const char *string) {
JSON_Value *value = json_value_init_string(string);
if (value == NULL) {
return JSONFailure;
}
if (json_array_append_value(array, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_append_string_with_len(JSON_Array *array, const char *string, size_t len) {
JSON_Value *value = json_value_init_string_with_len(string, len);
if (value == NULL) {
return JSONFailure;
}
if (json_array_append_value(array, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_append_number(JSON_Array *array, double number) {
JSON_Value *value = json_value_init_number(number);
if (value == NULL) {
return JSONFailure;
}
if (json_array_append_value(array, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_append_boolean(JSON_Array *array, int boolean) {
JSON_Value *value = json_value_init_boolean(boolean);
if (value == NULL) {
return JSONFailure;
}
if (json_array_append_value(array, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_array_append_null(JSON_Array *array) {
JSON_Value *value = json_value_init_null();
if (value == NULL) {
return JSONFailure;
}
if (json_array_append_value(array, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_object_set_value(JSON_Object *object, const char *name, JSON_Value *value) {
unsigned long hash = 0;
parson_bool_t found = PARSON_FALSE;
size_t cell_ix = 0;
size_t item_ix = 0;
JSON_Value *old_value = NULL;
char *key_copy = NULL;
if (!object || !name || !value || value->parent) {
return JSONFailure;
}
hash = hash_string(name, strlen(name));
found = PARSON_FALSE;
cell_ix = json_object_get_cell_ix(object, name, strlen(name), hash, &found);
if (found) {
item_ix = object->cells[cell_ix];
old_value = object->values[item_ix];
json_value_free(old_value);
object->values[item_ix] = value;
value->parent = json_object_get_wrapping_value(object);
return JSONSuccess;
}
if (object->count >= object->item_capacity) {
JSON_Status res = json_object_grow_and_rehash(object);
if (res != JSONSuccess) {
return JSONFailure;
}
cell_ix = json_object_get_cell_ix(object, name, strlen(name), hash, &found);
}
key_copy = parson_strdup(name);
if (!key_copy) {
return JSONFailure;
}
object->names[object->count] = key_copy;
object->cells[cell_ix] = object->count;
object->values[object->count] = value;
object->cell_ixs[object->count] = cell_ix;
object->hashes[object->count] = hash;
object->count++;
value->parent = json_object_get_wrapping_value(object);
return JSONSuccess;
}
JSON_Status json_object_set_string(JSON_Object *object, const char *name, const char *string) {
JSON_Value *value = json_value_init_string(string);
JSON_Status status = json_object_set_value(object, name, value);
if (status != JSONSuccess) {
json_value_free(value);
}
return status;
}
JSON_Status json_object_set_string_with_len(JSON_Object *object, const char *name, const char *string, size_t len) {
JSON_Value *value = json_value_init_string_with_len(string, len);
JSON_Status status = json_object_set_value(object, name, value);
if (status != JSONSuccess) {
json_value_free(value);
}
return status;
}
JSON_Status json_object_set_number(JSON_Object *object, const char *name, double number) {
JSON_Value *value = json_value_init_number(number);
JSON_Status status = json_object_set_value(object, name, value);
if (status != JSONSuccess) {
json_value_free(value);
}
return status;
}
JSON_Status json_object_set_boolean(JSON_Object *object, const char *name, int boolean) {
JSON_Value *value = json_value_init_boolean(boolean);
JSON_Status status = json_object_set_value(object, name, value);
if (status != JSONSuccess) {
json_value_free(value);
}
return status;
}
JSON_Status json_object_set_null(JSON_Object *object, const char *name) {
JSON_Value *value = json_value_init_null();
JSON_Status status = json_object_set_value(object, name, value);
if (status != JSONSuccess) {
json_value_free(value);
}
return status;
}
JSON_Status json_object_dotset_value(JSON_Object *object, const char *name, JSON_Value *value) {
const char *dot_pos = NULL;
JSON_Value *temp_value = NULL, *new_value = NULL;
JSON_Object *temp_object = NULL, *new_object = NULL;
JSON_Status status = JSONFailure;
size_t name_len = 0;
char *name_copy = NULL;
if (object == NULL || name == NULL || value == NULL) {
return JSONFailure;
}
dot_pos = strchr(name, '.');
if (dot_pos == NULL) {
return json_object_set_value(object, name, value);
}
name_len = dot_pos - name;
temp_value = json_object_getn_value(object, name, name_len);
if (temp_value) {
/* Don't overwrite existing non-object (unlike json_object_set_value, but it shouldn't be changed at this point) */
if (json_value_get_type(temp_value) != JSONObject) {
return JSONFailure;
}
temp_object = json_value_get_object(temp_value);
return json_object_dotset_value(temp_object, dot_pos + 1, value);
}
new_value = json_value_init_object();
if (new_value == NULL) {
return JSONFailure;
}
new_object = json_value_get_object(new_value);
status = json_object_dotset_value(new_object, dot_pos + 1, value);
if (status != JSONSuccess) {
json_value_free(new_value);
return JSONFailure;
}
name_copy = parson_strndup(name, name_len);
if (!name_copy) {
json_object_dotremove_internal(new_object, dot_pos + 1, 0);
json_value_free(new_value);
return JSONFailure;
}
status = json_object_add(object, name_copy, new_value);
if (status != JSONSuccess) {
parson_free(name_copy);
json_object_dotremove_internal(new_object, dot_pos + 1, 0);
json_value_free(new_value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_object_dotset_string(JSON_Object *object, const char *name, const char *string) {
JSON_Value *value = json_value_init_string(string);
if (value == NULL) {
return JSONFailure;
}
if (json_object_dotset_value(object, name, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_object_dotset_string_with_len(JSON_Object *object, const char *name, const char *string, size_t len) {
JSON_Value *value = json_value_init_string_with_len(string, len);
if (value == NULL) {
return JSONFailure;
}
if (json_object_dotset_value(object, name, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_object_dotset_number(JSON_Object *object, const char *name, double number) {
JSON_Value *value = json_value_init_number(number);
if (value == NULL) {
return JSONFailure;
}
if (json_object_dotset_value(object, name, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_object_dotset_boolean(JSON_Object *object, const char *name, int boolean) {
JSON_Value *value = json_value_init_boolean(boolean);
if (value == NULL) {
return JSONFailure;
}
if (json_object_dotset_value(object, name, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_object_dotset_null(JSON_Object *object, const char *name) {
JSON_Value *value = json_value_init_null();
if (value == NULL) {
return JSONFailure;
}
if (json_object_dotset_value(object, name, value) != JSONSuccess) {
json_value_free(value);
return JSONFailure;
}
return JSONSuccess;
}
JSON_Status json_object_remove(JSON_Object *object, const char *name) {
return json_object_remove_internal(object, name, PARSON_TRUE);
}
JSON_Status json_object_dotremove(JSON_Object *object, const char *name) {
return json_object_dotremove_internal(object, name, PARSON_TRUE);
}
JSON_Status json_object_clear(JSON_Object *object) {
size_t i = 0;
if (object == NULL) {
return JSONFailure;
}
for (i = 0; i < json_object_get_count(object); i++) {
parson_free(object->names[i]);
object->names[i] = NULL;
json_value_free(object->values[i]);
object->values[i] = NULL;
}
object->count = 0;
for (i = 0; i < object->cell_capacity; i++) {
object->cells[i] = OBJECT_INVALID_IX;
}
return JSONSuccess;
}
JSON_Status json_validate(const JSON_Value *schema, const JSON_Value *value) {
JSON_Value *temp_schema_value = NULL, *temp_value = NULL;
JSON_Array *schema_array = NULL, *value_array = NULL;
JSON_Object *schema_object = NULL, *value_object = NULL;
JSON_Value_Type schema_type = JSONError, value_type = JSONError;
const char *key = NULL;
size_t i = 0, count = 0;
if (schema == NULL || value == NULL) {
return JSONFailure;
}
schema_type = json_value_get_type(schema);
value_type = json_value_get_type(value);
if (schema_type != value_type && schema_type != JSONNull) { /* null represents all values */
return JSONFailure;
}
switch (schema_type) {
case JSONArray:
schema_array = json_value_get_array(schema);
value_array = json_value_get_array(value);
count = json_array_get_count(schema_array);
if (count == 0) {
return JSONSuccess; /* Empty array allows all types */
}
/* Get first value from array, rest is ignored */
temp_schema_value = json_array_get_value(schema_array, 0);
for (i = 0; i < json_array_get_count(value_array); i++) {
temp_value = json_array_get_value(value_array, i);
if (json_validate(temp_schema_value, temp_value) != JSONSuccess) {
return JSONFailure;
}
}
return JSONSuccess;
case JSONObject:
schema_object = json_value_get_object(schema);
value_object = json_value_get_object(value);
count = json_object_get_count(schema_object);
if (count == 0) {
return JSONSuccess; /* Empty object allows all objects */
} else if (json_object_get_count(value_object) < count) {
return JSONFailure; /* Tested object mustn't have less name-value pairs than schema */
}
for (i = 0; i < count; i++) {
key = json_object_get_name(schema_object, i);
temp_schema_value = json_object_get_value(schema_object, key);
temp_value = json_object_get_value(value_object, key);
if (temp_value == NULL) {
return JSONFailure;
}
if (json_validate(temp_schema_value, temp_value) != JSONSuccess) {
return JSONFailure;
}
}
return JSONSuccess;
case JSONString: case JSONNumber: case JSONBoolean: case JSONNull:
return JSONSuccess; /* equality already tested before switch */
case JSONError: default:
return JSONFailure;
}
}
int json_value_equals(const JSON_Value *a, const JSON_Value *b) {
JSON_Object *a_object = NULL, *b_object = NULL;
JSON_Array *a_array = NULL, *b_array = NULL;
const JSON_String *a_string = NULL, *b_string = NULL;
const char *key = NULL;
size_t a_count = 0, b_count = 0, i = 0;
JSON_Value_Type a_type, b_type;
a_type = json_value_get_type(a);
b_type = json_value_get_type(b);
if (a_type != b_type) {
return PARSON_FALSE;
}
switch (a_type) {
case JSONArray:
a_array = json_value_get_array(a);
b_array = json_value_get_array(b);
a_count = json_array_get_count(a_array);
b_count = json_array_get_count(b_array);
if (a_count != b_count) {
return PARSON_FALSE;
}
for (i = 0; i < a_count; i++) {
if (!json_value_equals(json_array_get_value(a_array, i),
json_array_get_value(b_array, i))) {
return PARSON_FALSE;
}
}
return PARSON_TRUE;
case JSONObject:
a_object = json_value_get_object(a);
b_object = json_value_get_object(b);
a_count = json_object_get_count(a_object);
b_count = json_object_get_count(b_object);
if (a_count != b_count) {
return PARSON_FALSE;
}
for (i = 0; i < a_count; i++) {
key = json_object_get_name(a_object, i);
if (!json_value_equals(json_object_get_value(a_object, key),
json_object_get_value(b_object, key))) {
return PARSON_FALSE;
}
}
return PARSON_TRUE;
case JSONString:
a_string = json_value_get_string_desc(a);
b_string = json_value_get_string_desc(b);
if (a_string == NULL || b_string == NULL) {
return PARSON_FALSE; /* shouldn't happen */
}
return a_string->length == b_string->length &&
memcmp(a_string->chars, b_string->chars, a_string->length) == 0;
case JSONBoolean:
return json_value_get_boolean(a) == json_value_get_boolean(b);
case JSONNumber:
return fabs(json_value_get_number(a) - json_value_get_number(b)) < 0.000001; /* EPSILON */
case JSONError:
return PARSON_TRUE;
case JSONNull:
return PARSON_TRUE;
default:
return PARSON_TRUE;
}
}
JSON_Value_Type json_type(const JSON_Value *value) {
return json_value_get_type(value);
}
JSON_Object * json_object (const JSON_Value *value) {
return json_value_get_object(value);
}
JSON_Array * json_array(const JSON_Value *value) {
return json_value_get_array(value);
}
const char * json_string(const JSON_Value *value) {
return json_value_get_string(value);
}
size_t json_string_len(const JSON_Value *value) {
return json_value_get_string_len(value);
}
double json_number(const JSON_Value *value) {
return json_value_get_number(value);
}
int json_boolean(const JSON_Value *value) {
return json_value_get_boolean(value);
}
void json_set_allocation_functions(JSON_Malloc_Function malloc_fun, JSON_Free_Function free_fun) {
parson_malloc = malloc_fun;
parson_free = free_fun;
}
void json_set_escape_slashes(int escape_slashes) {
parson_escape_slashes = escape_slashes;
}
void json_set_float_serialization_format(const char *format) {
if (parson_float_format) {
parson_free(parson_float_format);
parson_float_format = NULL;
}
if (!format) {
parson_float_format = NULL;
return;
}
parson_float_format = parson_strdup(format);
}
void json_set_number_serialization_function(JSON_Number_Serialization_Function func) {
parson_number_serialization_function = func;
}
```
expserver/src/lib/parson/README.md
```c
## About
Parson is a lightweight [json](http://json.org) library written in C.
## Features
* Lightweight (only 2 files)
* Simple API
* Addressing json values with dot notation (similar to C structs or objects in most OO languages, e.g. "objectA.objectB.value")
* C89 compatible
* Test suites
## Installation
Run:
```
git clone https://github.com/kgabis/parson.git
```
and copy parson.h and parson.c to you source code tree.
Run ```make test``` to compile and run tests.
## Examples
### Parsing JSON
Here is a function, which prints basic commit info (date, sha and author) from a github repository.
```c
void print_commits_info(const char *username, const char *repo) {
JSON_Value *root_value;
JSON_Array *commits;
JSON_Object *commit;
size_t i;
char curl_command[512];
char cleanup_command[256];
char output_filename[] = "commits.json";
/* it ain't pretty, but it's not a libcurl tutorial */
sprintf(curl_command,
"curl -s \"https://api.github.com/repos/%s/%s/commits\" > %s",
username, repo, output_filename);
sprintf(cleanup_command, "rm -f %s", output_filename);
system(curl_command);
/* parsing json and validating output */
root_value = json_parse_file(output_filename);
if (json_value_get_type(root_value) != JSONArray) {
system(cleanup_command);
return;
}
/* getting array from root value and printing commit info */
commits = json_value_get_array(root_value);
printf("%-10.10s %-10.10s %s\n", "Date", "SHA", "Author");
for (i = 0; i < json_array_get_count(commits); i++) {
commit = json_array_get_object(commits, i);
printf("%.10s %.10s %s\n",
json_object_dotget_string(commit, "commit.author.date"),
json_object_get_string(commit, "sha"),
json_object_dotget_string(commit, "commit.author.name"));
}
/* cleanup code */
json_value_free(root_value);
system(cleanup_command);
}
```
Calling ```print_commits_info("torvalds", "linux");``` prints:
```
Date SHA Author
2012-10-15 dd8e8c4a2c David Rientjes
2012-10-15 3ce9e53e78 Michal Marek
2012-10-14 29bb4cc5e0 Randy Dunlap
2012-10-15 325adeb55e Ralf Baechle
2012-10-14 68687c842c Russell King
2012-10-14 ddffeb8c4d Linus Torvalds
...
```
### Persistence
In this example I'm using parson to save user information to a file and then load it and validate later.
```c
void persistence_example(void) {
JSON_Value *schema = json_parse_string("{\"name\":\"\"}");
JSON_Value *user_data = json_parse_file("user_data.json");
char buf[256];
const char *name = NULL;
if (user_data == NULL || json_validate(schema, user_data) != JSONSuccess) {
puts("Enter your name:");
scanf("%s", buf);
user_data = json_value_init_object();
json_object_set_string(json_object(user_data), "name", buf);
json_serialize_to_file(user_data, "user_data.json");
}
name = json_object_get_string(json_object(user_data), "name");
printf("Hello, %s.", name);
json_value_free(schema);
json_value_free(user_data);
return;
}
```
### Serialization
Creating JSON values is very simple thanks to the dot notation.
Object hierarchy is automatically created when addressing specific fields.
In the following example I create a simple JSON value containing basic information about a person.
```c
void serialization_example(void) {
JSON_Value *root_value = json_value_init_object();
JSON_Object *root_object = json_value_get_object(root_value);
char *serialized_string = NULL;
json_object_set_string(root_object, "name", "John Smith");
json_object_set_number(root_object, "age", 25);
json_object_dotset_string(root_object, "address.city", "Cupertino");
json_object_dotset_value(root_object, "contact.emails", json_parse_string("[\"email@example.com\",\"email2@example.com\"]"));
serialized_string = json_serialize_to_string_pretty(root_value);
puts(serialized_string);
json_free_serialized_string(serialized_string);
json_value_free(root_value);
}
```
Output:
```
{
"name": "John Smith",
"age": 25,
"address": {
"city": "Cupertino"
},
"contact": {
"emails": [
"email@example.com",
"email2@example.com"
]
}
}
```
## Contributing
I will always merge *working* bug fixes. However, if you want to add something new to the API, please create an "issue" on github for this first so we can discuss if it should end up in the library before you start implementing it.
Remember to follow parson's code style and write appropriate tests.
## My other projects
* [ape](https://github.com/kgabis/ape) - simple programming language implemented in C library
* [kgflags](https://github.com/kgabis/kgflags) - easy to use command-line flag parsing library
* [agnes](https://github.com/kgabis/agnes) - header-only NES emulation library
## License
[The MIT License (MIT)](http://opensource.org/licenses/mit-license.php)
```
xps_config.json
json
{
"server_name": "eXpServer",
"workers": 4,
"servers": [
{
"listeners": [{ "host": "0.0.0.0", "port": 8001 }],
"routes": [
{
"req_path": "/",
"type": "file_serve",
"dir_path": "../../",
"index": ["index.html"]
},
{
"req_path": "/hello",
"type": "redirect",
"http_status_code": 302,
"redirect_url": "http://localhost:8002/"
}
]
},
{
"listeners": [{ "host": "0.0.0.0", "port": 8002 }],
"routes": [
{
"req_path": "/",
"type": "reverse_proxy",
"upstreams": ["localhost:3000"]
}
]
},
{
"listeners": [{ "host": "0.0.0.0", "port": 8003 }],
"routes": [
{
"req_path": "/",
"type": "redirect",
"http_status_code": 302,
"redirect_url": "https://expserver.github.io"
}
]
}
]
}This JSON configuration describes the setup of the eXpServer. The workers denotes the number of cores to be created, 4 in this case. servers is an array containing configuration for individual servers. Each server includes listeners (IP and port bindings) and routes (handling of HTTP requests). The above given is an example configuration and can be modified to add more ports or changing the route types for a port.
xps_config
A new folder, config, is added for creating a server with the configurations mentioned in the JSON file provided. It enables accessing a JSON-based server configuration for a web server application. It relies on the Parson library to parse JSON and provides a structured approach to create, query, and destroy configurations. xps_config_create() creates the server with the parsed information of the provided JSON configuration file. xps_config_lookup() determines the appropriate server and route for an incoming request.
xps_config.h
The code below has the contents of the header file for xps_config. Have a look at it and make a copy of it in your codebase.
expserver/src/config/xps_config.h
```c
#ifndef XPS_CONFIG_H
#define XPS_CONFIG_H
#include "../xps.h"
struct xps_config_s {
const char *config_path;
const char *server_name;
u_int workers;
vec_void_t servers;
vec_void_t _all_listeners;
JSON_Value *_config_json;
};
struct xps_config_server_s {
vec_void_t listeners;
vec_void_t hostnames;
vec_void_t routes;
};
struct xps_config_listener_s {
const char *host;
u_int port;
};
struct xps_config_route_s {
const char *req_path;
const char *type;
const char *dir_path;
vec_void_t index;
// bool gzip_enable;
// int gzip_level;
// vec_void_t gzip_mime_types; // get default mime types and append the rest
// vec_void_t ip_whitelist;
// vec_void_t ip_blacklist;
vec_void_t upstreams;
// const char *load_balancing;
// u_long _round_robin_counter;
u_int http_status_code;
const char *redirect_url;
bool keep_alive;
};
enum xps_req_type_e { REQ_FILE_SERVE, REQ_REVERSE_PROXY, REQ_REDIRECT, REQ_METRICS, REQ_INVALID };
struct xps_config_lookup_s {
xps_req_type_t type;
/* file_serve */
char *file_path; // absolute path
char *dir_path; // absolute path
long file_start; // parse range header
// https://developer.mozilla.org/en-US/docs/Web/HTTP/Range_requests
long file_end;
// bool gzip_enable;
// int gzip_level; // -1 to 9
/* reverse_proxy */
const char *upstream;
/* redirect */
u_int http_status_code;
const char *redirect_url;
/* common */
bool keep_alive;
vec_void_t ip_whitelist;
vec_void_t ip_blacklist;
};
xps_config_t *xps_config_create(const char *config_path);
void xps_config_destroy(xps_config_t *config);
xps_config_lookup_t *xps_config_lookup(xps_config_t *config, xps_http_req_t *http_req,
xps_connection_t *client, int *error);
void xps_config_lookup_destroy(xps_config_lookup_t *config_lookup, xps_core_t *core);
#endif
```
The names of the structs and its fields are intuitive, try to go through each and understand its use.
The struct xps_config_s represents the overall configuration of the server.
The struct xps_config_server_s describes individual server configurations.
The struct xps_config_lookup_s represents a lookup result from configuration where xps_req_type_t type indicates thr type of request (REQ_FILE_SERVE, REQ_REVERSE_PROXY, etc.).
Fields file_path, dir_path, file_start used by a file server, upstream used by a reverse proxy server and http_status_code, redirect_url used by a redirect.
xps_config.c
The functions implemented are briefly explained below(do all the error checks for NULL as and when required) :
xps_config_create: Creates and initializes a configuration structure (xps_config_t) by parsing a JSON file at the specifiedconfig_path.
c
xps_config_t *xps_config_create(const char *config_path) {
/*assert*/
/*allocate mem for config*/
/*get config_json using json_parse_file*/
/*initialize fields of config object*/
JSON_Object *root_object = json_value_get_object(config_json);
...
/*initialize server_name,workers,servers fields - hint: use json_object_get_string
,json_object_get_number,json_object_get_array*/
for (size_t i = 0; i < json_array_get_count(servers); i++) {
/*fill this*/ = json_array_get_object(servers, i);
/*fill this*/ = malloc(sizeof(xps_config_server_t));
}
/*initialize and parse the server and push to servers list of config*/
}
/*parse all listeners*/
return config;
}xps_config_destroy: Cleans up and frees the memory allocated for the configuration object. Implement it by deallocating the servers and the corresponding listeners and routes. Also de-initialize the vectors.xps_config_lookup: Performs a lookup to find the correct configuration based on an HTTP request (xps_http_req_t) and client details (xps_connection_t).
c
xps_config_lookup_t *xps_config_lookup(xps_config_t *config, xps_http_req_t *http_req,
xps_connection_t *client, int *error) {
/*assert*/
*error = E_FAIL;
/*get host,keep_alive(connection),accept encoding,pathname from http_req*/
// Step 1: Find matching server block
int target_server_index = -1;
for (int i = 0;/*fill this*/; i++) {
xps_config_server_t *server = /*fill this*/
// Check if client listener is present in server
for (int j = 0; /*fill this*/; j++) {
/*fill this*/
if () {
has_matching_listener = true;
break;
}
}
if (!has_matching_listener)
continue;
/* Check if host header matches any hostname*/
if (has_matching_hostname) {
target_server_index = i;
break;
}
}
}
xps_config_server_t *server = config->servers.data[target_server_index];
/*Find matching route block*/
xps_config_route_t *route = /*fill this*/
/* Init values of lookup*/
// File serve
if (lookup->type == REQ_FILE_SERVE) {
char *resource_path = /*fill this*/
if (/*not abs path*/) {
/*fill this*/
}
if (is_file(resource_path)) {
/*fill this*/
}
else if (is_dir(resource_path)) {
/*fill this*/
}
return lookup;
}xps_config_lookup_destroy: Implement yourselfparse_server: Parses the server_object from the JSON configuration and populates thexps_config_server_tstructure. Extracts and initializes server listeners, hostnames, and routes. For each listener, it callsparse_listener, and for each route, it callsparse_route. It then stores the parsed information into the server structure. Implement it.parse_route: Parses the route configuration from the route_object in the JSON and fills thexps_config_route_tstructure. Extracts thereq_pathand type of the route (the route type could be file_serve, reverse_proxy, or redirect). Based on the route type, it extracts additional information such asdir_path(for file serving), upstreams (for reverse proxy), andredirect_url(for redirects). It also manages the index files for file serving routes. Implement it.parse_listener: Purpose: Parses listener configuration from the listener_object in the JSON and populates thexps_config_listener_tstructure. Extracts the host and port values for the listener and validates them. Populates the listener structure with this data. Implement it.parse_all_listener: The function iterates through all the servers and their listeners in the configuration. It checks whether each listener (identified by its host and port) already exists in the_all_listenersarray. If the listener doesn't exist, it adds it to the _all_listeners array. This ensures that all listeners are collected in_all_listeners, but duplicates (based on the same host and port) are avoided. Implement it.
Core Module - Modifications
- To
xps_core_sstruct, addconfigfield.xps_core_create()takes config as argument. - Remove creating listeners while starting the server as the listeners are created during the configuration set-up itself.
Session Module - Modifications
- Add the lookup field which is used to determine the type of the incoming request.
- In the
session_process_request()the lookup(to determine the type of request) is done and the request is processed with respect to its type.
c
/*config_lookup called*/
/*implementation for file server already given ,
implement in the case of type being reverse proxy*/
else if (lookup->type == REQ_REDIRECT) {
xps_http_res_t *http_res = xps_http_res_create(session->core, lookup->http_status_code);
xps_http_set_header(&http_res->headers, "Location", lookup->redirect_url);
xps_buffer_t *http_res_buff = xps_http_res_serialize(http_res);
set_to_client_buff(session, http_res_buff);
xps_http_res_destroy(http_res);
return;
}Main.c
Instead of creating a single core, multiple cores are created as specified in the configuration. Processes the command-line arguments to retrieve the configuration file path. The configuration is created which is followed by core creation.
c
int main(int argc, char *argv[]) {
signal(SIGINT, sigint_handler); //for handling ctrl+c
cliargs = xps_cliargs_create(argc, argv);//get commandline arguments
/*create config, create cores, start cores*/
}
int cores_create(xps_config_t *config) {
cores = malloc(sizeof(xps_core_t *) * config->workers);
// Create cores
for (int i = 0; /*fill this*/; i++) {
xps_core_t *core = xps_core_create(config);
if (core) {
cores[n_cores] = core;
n_cores += 1;
}
}
/* Create listeners*/
/*Duplicate and add listeners to cores*/
/* Initialize dup_listener values*/
/*Attach listener to loop*/
/*Add listener to 'listeners' list of core*/
}
}
/* Destory listeners*/
}
void cores_destroy() {
/*fill this*/
}
void sigint_handler(int signum) {
/*fill this*/
}Listener Module - Modifications
- Core is not used while creating listeners as now there are multiple cores attached to the config.
- Attaching the listener to the event loop and pushing to the listeners list of core is already done during the configuration set-up.
Additional utilities to be added
- Cliargs : To handle and store command-line arguments related to the configuration file path.
expserver/src/utils/xps_cliargs.h
```c
#ifndef XPS_CLIARGS_H
#define XPS_CLIARGS_H
#include "../xps.h"
struct xps_cliargs_s {
char *config_path;
};
xps_cliargs_t *xps_cliargs_create(int argc, char *argv[]);
void xps_cliargs_destroy(xps_cliargs_t *cilargs);
#endif
```
expserver/src/utils/xps_cliargs.c
```c
#include "../xps.h"
xps_cliargs_t *xps_cliargs_create(int argc, char *argv[]) {
if (argc < 2) {
printf("No config file path given\nUSAGE: xps <config_file_path>\n");
return NULL;
}
xps_cliargs_t *cliargs = malloc(sizeof(xps_cliargs_t));
if (cliargs == NULL) {
logger(LOG_ERROR, "xps_cliargs_create()", "malloc() failed for 'cliargs'");
return NULL;
}
if (is_abs_path(argv[1]))
cliargs->config_path = str_create(argv[1]);
else
cliargs->config_path = realpath(argv[1], NULL);
return cliargs;
}
void xps_cliargs_destroy(xps_cliargs_t *cliargs) {
assert(cliargs != NULL);
free(cliargs->config_path);
free(cliargs);
}
```
- Utility functions required for checking directory, file, absolute path.
expserver/src/utils/xps_utils.c
```c
char *str_create(const char *str) {
assert(str != NULL);
char *new_str = malloc(strlen(str) + 1);
if (new_str == NULL) {
logger(LOG_ERROR, "str_create()", "malloc() failed for 'new_str'");
return NULL;
}
strcpy(new_str, str);
return new_str;
}bool is_dir(const char *path) {
assert(path != NULL);
struct stat path_stat;
if (stat(path, &path_stat) != 0)
return false;
return S_ISDIR(path_stat.st_mode);
}
bool is_file(const char *path) {
assert(path != NULL);
struct stat path_stat;
if (stat(path, &path_stat) != 0)
return false;
return S_ISREG(path_stat.st_mode);
}
bool is_abs_path(const char *path) {
assert(path != NULL);
return path[0] == '/';
}
```
Also update xps_utils.h accordingly.
Also update xps.h to reflect all the changes so far added in this stage.
Milestone #1
First we have to run the server by giving the JSON file containing the configuration information as command line argument.
Three port would be created as given:
- First, we would be verifying the file server functionality. An
index.htmlfile as mentioned in the xps_config.json is created in the src folder. Add some standard html code in this file. The contents can be viewed on[localhost:8001](http://localhost:8001)on the browser.
Try by replacing files of different format. You have to update JSON configuration file accordingly.
Now, run a python file server as done earlier in Phase 0.
This will create the upstream server mentioned in xps_config.json.
The files in the directory in which the python server is running can be viewed from the urls [localhost:8001/hello] and [localhost:8002] . In this case, the url is redirected to the second one.
localhost:8003would be redirecting to theredirect_urlmentioned in the JSON configuration file.
Try adding more ports and redirect to different urls.
Experiment #1
In the port 8001 mentioned in the JSON configuration file, try opening files outside the src folder. The file name can be given along with the url in the browser. Also try by changing the path in configuration file.