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#include <dtree/dtree.h>
#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>
#include "jsmn.h"
#define DTREE_TOK_BOOLEAN (1 << 1)
#define DTREE_TOK_NUMERICAL (1 << 2)
#define DTREE_TOK_LITERAL (1 << 3)
char *tok_to_str(jsmntype_t *tok)
{
switch(*tok) {
case JSMN_UNDEFINED: return "UNDEFINED";
case JSMN_OBJECT: return "OBJECT";
case JSMN_ARRAY: return "ARRAY";
case JSMN_STRING: return "STRING";
case JSMN_PRIMITIVE: return "PRIMITIVE";
default: return "UNKNOWN";
}
}
int digest_payload(const char *token)
{
char* end;
size_t len = strlen(token);
if(len == strlen("true") || len == strlen("false"))
if(strcmp(token, "true") == 0 || strcmp(token, "false") == 0)
return DTREE_TOK_BOOLEAN;
/* It could still be a number! */
strtol(token, &end, 10);
if (!*end) return DTREE_TOK_NUMERICAL;
return DTREE_TOK_LITERAL;
}
dt_err dtree_decode_json(dtree *(*data), const char *json_data, size_t len)
{
jsmn_parser parse;
jsmn_init(&parse);
// FIXME: Variable amount of tokens?
jsmntok_t *tokens = malloc(sizeof(jsmntok_t) * len);
memset(tokens, 0, sizeof(jsmntok_t) * len);
int ret = jsmn_parse(&parse, json_data, strlen(json_data), tokens, sizeof(tokens) / sizeof(tokens[0]));
jsmntok_t tok;
unsigned int idx = 0;
/** Prepare dtree nodes */
dtree *root, *curr;
dtree_malloc(&root);
curr = root;
struct bounds {
int low, high;
};
struct pair {
short state;
#define TOK_PAIR_KEYED 1
#define TOK_PAIR_VALUED 2
char key[1024];
union value {
char string[1024];
unsigned long num;
} value;
};
/* Save some space to store token bounds */
struct bounds *bounds = malloc(sizeof(struct bounds) * len);
memset(bounds, 0, sizeof(struct bounds) * len);
int focused = -1;
struct pair c_pair;
memset(&c_pair, 0, sizeof(struct pair));
while(tok = tokens[idx++], tok.type != NULL) {
size_t tok_len = (size_t) tok.end - tok.start;
char token[tok_len];
memset(token, 0, tok_len);
memcpy(token, json_data + tok.start, tok_len);
/** Check if we need to move the boundry scope (again) */
if(focused > 0 && tok.end >= bounds[focused].high) {
focused--;
/* Because of how our root node is a VALUE node, we need the parents parent */
dtree *parent, *pair_parent;
dtree_parent(root, curr, &parent);
dtree_parent(root, parent, &pair_parent);
/* Assign the new root node - old scope restored */
curr = pair_parent;
}
switch(tok.type) {
/**
* When we encounter a new json object, shift our "focus" over by one so we can
* record in what range this object is going to accumilate tokens.
*
* We then create a new child node under the current root node and switch the
* curr root pointer over to that child.
*
* When we reach the end of the token scope, we need to re-reference the parent as
* current root and switch over our boundry scope as well. This is done before the
* parsing switch statement.
*/
case JSMN_OBJECT:
{
focused++;
bounds[focused].low = tok.start;
bounds[focused].high = tok.end;
/**
* Most of the time, we will create a new object under the key of
* a pair. This is the case, when the c_pair state buffer has been
* set to KEYED. In this case we allocate a new pair node for key
* and value and set that value to the new root.
*/
if(c_pair.state == TOK_PAIR_KEYED) {
/* Create pair nodes & new_root which becomes curr */
dtree *pair, *key, *val;
dtree_addlist(curr, &pair);
dtree_addpair(pair, &key, &val);
/* Assign key and new_root as a value of the pair */
dtree_addliteral(key, c_pair.key);
/* Move curr root pointer */
curr = val;
/* Blank c_pair data for next tokens */
memset(&c_pair, 0, sizeof(struct pair));
}
/* Skip to next token */
continue;
}
case JSMN_STRING:
{
/**
* Here we need to check if we are adding a string as a key
* or as a value. This is simply done by checking for the existance
* of a key in the c_pair (current pair) variable.
*
* We know the token positions so we can manualy copy from the json stream
*/
if(c_pair.state == 0) {
memcpy(c_pair.key, json_data + tok.start, (size_t) tok.end - tok.start);
c_pair.state = TOK_PAIR_KEYED;
} else if(c_pair.state == TOK_PAIR_KEYED){
/** Create a PAIR node under current root */
dtree *pair, *key, *val;
dtree_addlist(curr, &pair);
dtree_addpair(pair, &key, &val);
/* Key is always literal */
dtree_addliteral(key, c_pair.key);
/* Parse payload and asign to value node */
switch(digest_payload(token)) {
case DTREE_TOK_LITERAL:
dtree_addliteral(val, token);
break;
case DTREE_TOK_NUMERICAL:
dtree_addnumeral(val, atol(token));
break;
default: continue;
}
/* Blank c_pair data for next tokens */
memset(&c_pair, 0, sizeof(struct pair));
}
/* Skip to next token */
continue;
}
default:
continue;
}
}
/* Switch over data pointer and return */
(*data) = root;
return SUCCESS;
}
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