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-rw-r--r--libnetdata/json/jsmn.c328
1 files changed, 328 insertions, 0 deletions
diff --git a/libnetdata/json/jsmn.c b/libnetdata/json/jsmn.c
new file mode 100644
index 00000000..2f48bd65
--- /dev/null
+++ b/libnetdata/json/jsmn.c
@@ -0,0 +1,328 @@
+#include <stdlib.h>
+
+#include "jsmn.h"
+
+/**
+ * Alloc token
+ *
+ * Allocates a fresh unused token from the token pull.
+ *
+ * @param parser the controller
+ * @param tokens the tokens I am working
+ * @param num_tokens the number total of tokens.
+ *
+ * @return it returns the next token to work.
+ */
+static jsmntok_t *jsmn_alloc_token(jsmn_parser *parser,
+ jsmntok_t *tokens, size_t num_tokens) {
+ jsmntok_t *tok;
+ if (parser->toknext >= num_tokens) {
+ return NULL;
+ }
+ tok = &tokens[parser->toknext++];
+ tok->start = tok->end = -1;
+ tok->size = 0;
+#ifdef JSMN_PARENT_LINKS
+ tok->parent = -1;
+#endif
+ return tok;
+}
+
+/**
+ * Fill Token
+ *
+ * Fills token type and boundaries.
+ *
+ * @param token the structure to set the values
+ * @param type is the token type
+ * @param start is the first position of the value
+ * @param end is the end of the value
+ */
+static void jsmn_fill_token(jsmntok_t *token, jsmntype_t type,
+ int start, int end) {
+ token->type = type;
+ token->start = start;
+ token->end = end;
+ token->size = 0;
+}
+
+/**
+ * Parse primitive
+ *
+ * Fills next available token with JSON primitive.
+ *
+ * @param parser is the control structure
+ * @param js is the json string
+ * @param type is the token type
+ */
+static jsmnerr_t jsmn_parse_primitive(jsmn_parser *parser, const char *js,
+ size_t len, jsmntok_t *tokens, size_t num_tokens) {
+ jsmntok_t *token;
+ int start;
+
+ start = parser->pos;
+
+ for (; parser->pos < len && js[parser->pos] != '\0'; parser->pos++) {
+ switch (js[parser->pos]) {
+#ifndef JSMN_STRICT
+ /* In strict mode primitive must be followed by "," or "}" or "]" */
+ case ':':
+#endif
+ case '\t' : case '\r' : case '\n' : case ' ' :
+ case ',' : case ']' : case '}' :
+ goto found;
+ }
+ if (js[parser->pos] < 32 || js[parser->pos] >= 127) {
+ parser->pos = start;
+ return JSMN_ERROR_INVAL;
+ }
+ }
+#ifdef JSMN_STRICT
+ /* In strict mode primitive must be followed by a comma/object/array */
+ parser->pos = start;
+ return JSMN_ERROR_PART;
+#endif
+
+ found:
+ if (tokens == NULL) {
+ parser->pos--;
+ return 0;
+ }
+ token = jsmn_alloc_token(parser, tokens, num_tokens);
+ if (token == NULL) {
+ parser->pos = start;
+ return JSMN_ERROR_NOMEM;
+ }
+ jsmn_fill_token(token, JSMN_PRIMITIVE, start, parser->pos);
+#ifdef JSMN_PARENT_LINKS
+ token->parent = parser->toksuper;
+#endif
+ parser->pos--;
+ return 0;
+}
+
+/**
+ * Parse string
+ *
+ * Fills next token with JSON string.
+ *
+ * @param parser is the control structure
+ * @param js is the json string
+ * @param len is the js length
+ * @param tokens is structure with the tokens mapped.
+ * @param num_tokens is the total number of tokens
+ *
+ * @return It returns 0 on success and another integer otherwise
+ */
+static jsmnerr_t jsmn_parse_string(jsmn_parser *parser, const char *js,
+ size_t len, jsmntok_t *tokens, size_t num_tokens) {
+ jsmntok_t *token;
+
+ int start = parser->pos;
+
+ parser->pos++;
+
+ /* Skip starting quote */
+ for (; parser->pos < len && js[parser->pos] != '\0'; parser->pos++) {
+ char c = js[parser->pos];
+
+ /* Quote: end of string */
+ if (c == '\"') {
+ if (tokens == NULL) {
+ return 0;
+ }
+ token = jsmn_alloc_token(parser, tokens, num_tokens);
+ if (token == NULL) {
+ parser->pos = start;
+ return JSMN_ERROR_NOMEM;
+ }
+ jsmn_fill_token(token, JSMN_STRING, start+1, parser->pos);
+#ifdef JSMN_PARENT_LINKS
+ token->parent = parser->toksuper;
+#endif
+ return 0;
+ }
+
+ /* Backslash: Quoted symbol expected */
+ if (c == '\\') {
+ parser->pos++;
+ switch (js[parser->pos]) {
+ /* Allowed escaped symbols */
+ case '\"': case '/' : case '\\' : case 'b' :
+ case 'f' : case 'r' : case 'n' : case 't' :
+ break;
+ /* Allows escaped symbol \uXXXX */
+ case 'u':
+ parser->pos++;
+ int i = 0;
+ for(; i < 4 && js[parser->pos] != '\0'; i++) {
+ /* If it isn't a hex character we have an error */
+ if(!((js[parser->pos] >= 48 && js[parser->pos] <= 57) || /* 0-9 */
+ (js[parser->pos] >= 65 && js[parser->pos] <= 70) || /* A-F */
+ (js[parser->pos] >= 97 && js[parser->pos] <= 102))) { /* a-f */
+ parser->pos = start;
+ return JSMN_ERROR_INVAL;
+ }
+ parser->pos++;
+ }
+ parser->pos--;
+ break;
+ /* Unexpected symbol */
+ default:
+ parser->pos = start;
+ return JSMN_ERROR_INVAL;
+ }
+ }
+ }
+ parser->pos = start;
+ return JSMN_ERROR_PART;
+}
+
+/**
+ * JSMN Parse
+ *
+ * Parse JSON string and fill tokens.
+ *
+ * @param parser the auxiliary vector used to parser
+ * @param js the string to parse
+ * @param len the string length
+ * @param tokens the place to map the tokens
+ * @param num_tokens the number of tokens present in the tokens structure.
+ *
+ * @return It returns the number of tokens present in the string on success or a negative number otherwise
+ */
+jsmnerr_t jsmn_parse(jsmn_parser *parser, const char *js, size_t len,
+ jsmntok_t *tokens, unsigned int num_tokens) {
+ jsmnerr_t r;
+ int i;
+ jsmntok_t *token;
+ int count = 0;
+
+ for (; parser->pos < len && js[parser->pos] != '\0'; parser->pos++) {
+ char c;
+ jsmntype_t type;
+
+ c = js[parser->pos];
+ switch (c) {
+ case '{': case '[':
+ count++;
+ if (tokens == NULL) {
+ break;
+ }
+ token = jsmn_alloc_token(parser, tokens, num_tokens);
+ if (token == NULL)
+ return JSMN_ERROR_NOMEM;
+ if (parser->toksuper != -1) {
+ tokens[parser->toksuper].size++;
+#ifdef JSMN_PARENT_LINKS
+ token->parent = parser->toksuper;
+#endif
+ }
+ token->type = (c == '{' ? JSMN_OBJECT : JSMN_ARRAY);
+ token->start = parser->pos;
+ parser->toksuper = parser->toknext - 1;
+ break;
+ case '}': case ']':
+ if (tokens == NULL)
+ break;
+ type = (c == '}' ? JSMN_OBJECT : JSMN_ARRAY);
+#ifdef JSMN_PARENT_LINKS
+ if (parser->toknext < 1) {
+ return JSMN_ERROR_INVAL;
+ }
+ token = &tokens[parser->toknext - 1];
+ for (;;) {
+ if (token->start != -1 && token->end == -1) {
+ if (token->type != type) {
+ return JSMN_ERROR_INVAL;
+ }
+ token->end = parser->pos + 1;
+ parser->toksuper = token->parent;
+ break;
+ }
+ if (token->parent == -1) {
+ break;
+ }
+ token = &tokens[token->parent];
+ }
+#else
+ for (i = parser->toknext - 1; i >= 0; i--) {
+ token = &tokens[i];
+ if (token->start != -1 && token->end == -1) {
+ if (token->type != type) {
+ return JSMN_ERROR_INVAL;
+ }
+ parser->toksuper = -1;
+ token->end = parser->pos + 1;
+ break;
+ }
+ }
+ /* Error if unmatched closing bracket */
+ if (i == -1) return JSMN_ERROR_INVAL;
+ for (; i >= 0; i--) {
+ token = &tokens[i];
+ if (token->start != -1 && token->end == -1) {
+ parser->toksuper = i;
+ break;
+ }
+ }
+#endif
+ break;
+ case '\"':
+ r = jsmn_parse_string(parser, js, len, tokens, num_tokens);
+ if (r < 0) return r;
+ count++;
+ if (parser->toksuper != -1 && tokens != NULL)
+ tokens[parser->toksuper].size++;
+ break;
+ case '\t' : case '\r' : case '\n' : case ':' : case ',': case ' ':
+ break;
+#ifdef JSMN_STRICT
+ /* In strict mode primitives are: numbers and booleans */
+ case '-': case '0': case '1' : case '2': case '3' : case '4':
+ case '5': case '6': case '7' : case '8': case '9':
+ case 't': case 'f': case 'n' :
+#else
+ /* In non-strict mode every unquoted value is a primitive */
+ default:
+#endif
+ r = jsmn_parse_primitive(parser, js, len, tokens, num_tokens);
+ if (r < 0) return r;
+ count++;
+ if (parser->toksuper != -1 && tokens != NULL)
+ tokens[parser->toksuper].size++;
+ break;
+
+#ifdef JSMN_STRICT
+ /* Unexpected char in strict mode */
+ default:
+ return JSMN_ERROR_INVAL;
+#endif
+ }
+ }
+
+ if (tokens) {
+ for (i = parser->toknext - 1; i >= 0; i--) {
+ /* Unmatched opened object or array */
+ if (tokens[i].start != -1 && tokens[i].end == -1) {
+ return JSMN_ERROR_PART;
+ }
+ }
+ }
+
+ return count;
+}
+
+/**
+ * JSMN Init
+ *
+ * Creates a new parser based over a given buffer with an array of tokens
+ * available.
+ *
+ * @param parser is the structure with values to reset
+ */
+void jsmn_init(jsmn_parser *parser) {
+ parser->pos = 0;
+ parser->toknext = 0;
+ parser->toksuper = -1;
+} \ No newline at end of file