eni_json

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "examples/eni/json/jsmn"]
+	path = examples/eni/json/jsmn
+	url = https://github.com/zserge/jsmn

examples/eni/CMakeLists.txt

@@ -2,3 +2,8 @@ add_eni_library(eni_reverse
   SRCS reverse/eni_reverse.cpp
   LIBS eni
 )
+
+add_eni_library(eni_json
+  SRCS json/eni_json.cpp
+  LIBS eni
+)

examples/eni/json/eni_json.cpp

@@ -0,0 +1,137 @@
+/*==- examples/eni/reverse/eni_reverse.cpp ---------------------------------==
+
+  This file is part of the Lity project distributed under GPL-3.0.
+  See LICENSE for details.
+
+==------------------------------------------------------------------------==*/
+#include <eni.h>
+#include <json/Parser.h>
+
+#include "jsmn/jsmn.h"
+
+namespace {
+std::string parseString(const std::string& raw) { return json::Parser(raw).getRoot().toString(); }
+std::vector<jsmntok_t> internalParse(const char* data, int start, int end) {
+    jsmn_parser p;
+    p.pos = start;
+    p.toknext = 0;
+    p.toksuper = -1;
+    int len = jsmn_parse(&p, data, end, 0, 0);
+    std::vector<jsmntok_t> result(len);
+    p.pos = start;
+    p.toknext = 0;
+    p.toksuper = -1;
+    jsmn_parse(&p, data, end, result.data(), len);
+    return result;
+}
+std::string encodeToken(const jsmntok_t& tok) {
+    union {
+        char s[8];
+        uint32_t v[2];
+    };
+    v[0] = htobe32(tok.start - (tok.type == JSMN_STRING));
+    v[1] = htobe32(tok.end + (tok.type == JSMN_STRING));
+    return std::string(s, 8);
+}
+std::vector<jsmntok_t> arrayTokens(const char* data, int start, int end) {
+    auto tokens = internalParse(data, start, end);
+    std::vector<jsmntok_t> result;
+    int after = tokens[0].start;
+    int before = tokens[0].end;
+    for (int i = 1; i < tokens.size(); i++) {
+        if (tokens[i].start < after) {
+            continue;
+        }
+        if (tokens[i].start > before) {
+            break;
+        }
+        result.push_back(tokens[i]);
+        after = tokens[i].end;
+    }
+    return result;
+}
+std::string parseArray(const char* data, int start, int end) {
+    std::string result;
+    for (const auto& tok: arrayTokens(data, start, end)) {
+        result += encodeToken(tok);
+    }
+    return result;
+}
+std::string arrayGet(const char* data, int start, int end, int index) {
+    auto tokens = arrayTokens(data, start, end);
+    return encodeToken(tokens[index]);
+}
+
+std::map<std::string, jsmntok_t> objectTokens(const char* data, int start, int end) {
+    auto tokens = internalParse(data, start, end);
+    std::map<std::string, jsmntok_t> result;
+    int after = tokens[0].start;
+    int before = tokens[0].end;
+    int key_token = 0;
+    auto getkey = [&] {
+        auto& tok = tokens[key_token];
+        return parseString(std::string(data + tok.start - 1, data + tok.end + 1));
+    };
+    for (int i = 1; i < tokens.size(); i++) {
+        if (tokens[i].start < after) {
+            continue;
+        }
+        if (tokens[i].start > before) {
+            break;
+        }
+        if (key_token == 0) {
+            key_token = i;
+        } else {
+            result[getkey()] = tokens[i];
+        }
+        after = tokens[i].end;
+    }
+    return result;
+}
+
+std::string objectGet(const char* data, int start, int end, const std::string& key) {
+    auto tokens = objectTokens(data, start, end);
+    return encodeToken(tokens[key]);
+}
+}  // namespace
+
+class JSON : public eni::EniBase {
+public:
+    JSON(const std::string& pArgStr) : eni::EniBase(pArgStr) {}
+
+    ~JSON() {}
+
+private:
+    bool parse(const json::Array& pArgs) override {
+        std::string op = pArgs[0].toString();
+        std::string data = pArgs[1].toString();
+        int begin = (int)pArgs[2].toInteger();
+        int end = (int)pArgs[3].toInteger();
+        if (op == "parseString") {
+            m_Str = parseString(std::string(data.data(), begin, end));
+        } else if (op == "parseArray") {
+            m_Str = parseArray(data.data(), begin, end);
+        } else if (op == "arrayGet") {
+            m_Str = arrayGet(data.data(), begin, end, (int)pArgs[4].toInteger());
+        } else if (op == "objectGet") {
+            m_Str = objectGet(data.data(), begin, end, pArgs[4].toString());
+        } else {
+            return false;
+        }
+        m_Str = pArgs[0].toString();
+        return true;
+    }
+
+    eni::Gas gas() const override { return 0; }
+
+    bool run(json::Array& pRetVal) override {
+        std::string ret(m_Str.rbegin(), m_Str.rend());
+        pRetVal.emplace_back(ret);
+        return true;
+    }
+
+private:
+    std::string m_Str;
+};
+
+ENI_C_INTERFACE(json, JSON)