Add "bitcoin-tx" command line utility and supporting modules.

This is a simple utility that provides command line manipulation of
a hex-encoded TX. The utility takes a hex string on the command line
as input, performs zero or more mutations, and outputs a hex string
to standard output.

This utility is also an intentional exercise of the "bitcoin library"
concept. It is designed to require minimal libraries, and works
entirely without need for any RPC or P2P communication.

See "bitcoin-tx --help" for command and options summary.

4 files changed, 925 insertions, 0 deletions

diff --git a/src/univalue/univalue.cpp b/src/univalue/univalue.cpp
new file mode 100644
index 0000000000..e577aa8ee4
--- /dev/null
+++ b/src/univalue/univalue.cpp
@@ -0,0 +1,233 @@
+// Copyright 2014 BitPay Inc.
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <stdint.h>
+#include <ctype.h>
+#include <sstream>
+#include "univalue.h"
+
+using namespace std;
+
+static const UniValue nullValue;
+
+void UniValue::clear()
+{
+    typ = VNULL;
+    val.clear();
+    keys.clear();
+    values.clear();
+}
+
+bool UniValue::setNull()
+{
+    clear();
+    return true;
+}
+
+bool UniValue::setBool(bool val_)
+{
+    clear();
+    typ = VBOOL;
+    if (val_)
+        val = "1";
+    return true;
+}
+
+static bool validNumStr(const string& s)
+{
+    string tokenVal;
+    unsigned int consumed;
+    enum jtokentype tt = getJsonToken(tokenVal, consumed, s.c_str());
+    return (tt == JTOK_NUMBER);
+}
+
+bool UniValue::setNumStr(const string& val_)
+{
+    if (!validNumStr(val))
+        return false;
+
+    clear();
+    typ = VNUM;
+    val = val_;
+    return true;
+}
+
+bool UniValue::setInt(uint64_t val)
+{
+    string s;
+    ostringstream oss;
+
+    oss << val;
+
+    return setNumStr(oss.str());
+}
+
+bool UniValue::setInt(int64_t val)
+{
+    string s;
+    ostringstream oss;
+
+    oss << val;
+
+    return setNumStr(oss.str());
+}
+
+bool UniValue::setFloat(double val)
+{
+    string s;
+    ostringstream oss;
+
+    oss << val;
+
+    return setNumStr(oss.str());
+}
+
+bool UniValue::setStr(const string& val_)
+{
+    clear();
+    typ = VSTR;
+    val = val_;
+    return true;
+}
+
+bool UniValue::setArray()
+{
+    clear();
+    typ = VARR;
+    return true;
+}
+
+bool UniValue::setObject()
+{
+    clear();
+    typ = VOBJ;
+    return true;
+}
+
+bool UniValue::push_back(const UniValue& val)
+{
+    if (typ != VARR)
+        return false;
+
+    values.push_back(val);
+    return true;
+}
+
+bool UniValue::push_backV(const std::vector<UniValue>& vec)
+{
+    if (typ != VARR)
+        return false;
+
+    values.insert(values.end(), vec.begin(), vec.end());
+
+    return true;
+}
+
+bool UniValue::pushKV(const std::string& key, const UniValue& val)
+{
+    if (typ != VOBJ)
+        return false;
+
+    keys.push_back(key);
+    values.push_back(val);
+    return true;
+}
+
+bool UniValue::pushKVs(const UniValue& obj)
+{
+    if (typ != VOBJ || obj.typ != VOBJ)
+        return false;
+
+    for (unsigned int i = 0; i < obj.keys.size(); i++) {
+        keys.push_back(obj.keys[i]);
+        values.push_back(obj.values[i]);
+    }
+
+    return true;
+}
+
+bool UniValue::getArray(std::vector<UniValue>& arr)
+{
+    if (typ != VARR)
+        return false;
+
+    arr = values;
+    return true;
+}
+
+bool UniValue::getObject(std::map<std::string,UniValue>& obj)
+{
+    if (typ != VOBJ)
+        return false;
+
+    obj.clear();
+    for (unsigned int i = 0; i < keys.size(); i++) {
+        obj[keys[i]] = values[i];
+    }
+
+    return true;
+}
+
+int UniValue::findKey(const std::string& key) const
+{
+    for (unsigned int i = 0; i < keys.size(); i++) {
+        if (keys[i] == key)
+            return (int) i;
+    }
+
+    return -1;
+}
+
+bool UniValue::checkObject(const std::map<std::string,UniValue::VType>& t)
+{
+    for (std::map<std::string,UniValue::VType>::const_iterator it = t.begin();
+         it != t.end(); it++) {
+        int idx = findKey(it->first);
+        if (idx < 0)
+            return false;
+
+        if (values[idx].getType() != it->second)
+            return false;
+    }
+
+    return true;
+}
+
+const UniValue& UniValue::operator[](const std::string& key) const
+{
+    if (typ != VOBJ)
+        return nullValue;
+
+    int index = findKey(key);
+    if (index < 0)
+        return nullValue;
+
+    return values[index];
+}
+
+const UniValue& UniValue::operator[](unsigned int index) const
+{
+    if (typ != VOBJ && typ != VARR)
+        return nullValue;
+    if (index >= values.size())
+        return nullValue;
+
+    return values[index];
+}
+
+const char *uvTypeName(UniValue::VType t)
+{
+    switch (t) {
+    case UniValue::VNULL: return "null";
+    case UniValue::VBOOL: return "bool";
+    case UniValue::VOBJ: return "object";
+    case UniValue::VARR: return "array";
+    case UniValue::VSTR: return "string";
+    case UniValue::VNUM: return "number";
+    }
+
+    // not reached
+    return NULL;
+}
+
diff --git a/src/univalue/univalue.h b/src/univalue/univalue.h
new file mode 100644
index 0000000000..5e94b6ba23
--- /dev/null
+++ b/src/univalue/univalue.h
@@ -0,0 +1,157 @@
+// Copyright 2014 BitPay Inc.
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef __UNIVALUE_H__
+#define __UNIVALUE_H__
+
+#include <stdint.h>
+#include <string>
+#include <vector>
+#include <map>
+#include <cassert>
+
+class UniValue {
+public:
+    enum VType { VNULL, VOBJ, VARR, VSTR, VNUM, VBOOL, };
+
+    UniValue() { typ = VNULL; }
+    UniValue(UniValue::VType initialType, const std::string& initialStr = "") {
+        typ = initialType;
+        val = initialStr;
+    }
+    UniValue(uint64_t val_) {
+        setInt(val_);
+    }
+    UniValue(int64_t val_) {
+        setInt(val_);
+    }
+    UniValue(int val_) {
+        setInt(val_);
+    }
+    UniValue(double val_) {
+        setFloat(val_);
+    }
+    UniValue(const std::string& val_) {
+        setStr(val_);
+    }
+    UniValue(const char *val_) {
+        std::string s(val_);
+        setStr(s);
+    }
+    ~UniValue() {}
+
+    void clear();
+
+    bool setNull();
+    bool setBool(bool val);
+    bool setNumStr(const std::string& val);
+    bool setInt(uint64_t val);
+    bool setInt(int64_t val);
+    bool setInt(int val) { return setInt((int64_t)val); }
+    bool setFloat(double val);
+    bool setStr(const std::string& val);
+    bool setArray();
+    bool setObject();
+
+    enum VType getType() const { return typ; }
+    std::string getValStr() const { return val; }
+    bool empty() const { return (values.size() == 0); }
+
+    size_t count() const { return values.size(); }
+
+    bool getBool() const { return isTrue(); }
+    bool getArray(std::vector<UniValue>& arr);
+    bool getObject(std::map<std::string,UniValue>& obj);
+    bool checkObject(const std::map<std::string,UniValue::VType>& memberTypes);
+    const UniValue& operator[](const std::string& key) const;
+    const UniValue& operator[](unsigned int index) const;
+    bool exists(const std::string& key) const { return (findKey(key) >= 0); }
+
+    bool isNull() const { return (typ == VNULL); }
+    bool isTrue() const { return (typ == VBOOL) && (val == "1"); }
+    bool isFalse() const { return (!isTrue()); }
+    bool isBool() const { return (typ == VBOOL); }
+    bool isStr() const { return (typ == VSTR); }
+    bool isNum() const { return (typ == VNUM); }
+    bool isArray() const { return (typ == VARR); }
+    bool isObject() const { return (typ == VOBJ); }
+
+    bool push_back(const UniValue& val);
+    bool push_back(const std::string& val_) {
+        UniValue tmpVal(VSTR, val_);
+        return push_back(tmpVal);
+    }
+    bool push_back(const char *val_) {
+        std::string s(val_);
+        return push_back(s);
+    }
+    bool push_backV(const std::vector<UniValue>& vec);
+
+    bool pushKV(const std::string& key, const UniValue& val);
+    bool pushKV(const std::string& key, const std::string& val) {
+        UniValue tmpVal(VSTR, val);
+        return pushKV(key, tmpVal);
+    }
+    bool pushKV(const std::string& key, const char *val_) {
+        std::string val(val_);
+        return pushKV(key, val);
+    }
+    bool pushKV(const std::string& key, int64_t val) {
+        UniValue tmpVal(val);
+        return pushKV(key, tmpVal);
+    }
+    bool pushKV(const std::string& key, uint64_t val) {
+        UniValue tmpVal(val);
+        return pushKV(key, tmpVal);
+    }
+    bool pushKV(const std::string& key, int val) {
+        UniValue tmpVal((int64_t)val);
+        return pushKV(key, tmpVal);
+    }
+    bool pushKV(const std::string& key, double val) {
+        UniValue tmpVal(val);
+        return pushKV(key, tmpVal);
+    }
+    bool pushKVs(const UniValue& obj);
+
+    std::string write(unsigned int prettyIndent = 0,
+                      unsigned int indentLevel = 0) const;
+
+    bool read(const char *raw);
+    bool read(const std::string& rawStr) {
+        return read(rawStr.c_str());
+    }
+
+private:
+    UniValue::VType typ;
+    std::string val;                       // numbers are stored as C++ strings
+    std::vector<std::string> keys;
+    std::vector<UniValue> values;
+
+    int findKey(const std::string& key) const;
+    void writeArray(unsigned int prettyIndent, unsigned int indentLevel, std::string& s) const;
+    void writeObject(unsigned int prettyIndent, unsigned int indentLevel, std::string& s) const;
+};
+
+enum jtokentype {
+    JTOK_ERR        = -1,
+    JTOK_NONE       = 0,                           // eof
+    JTOK_OBJ_OPEN,
+    JTOK_OBJ_CLOSE,
+    JTOK_ARR_OPEN,
+    JTOK_ARR_CLOSE,
+    JTOK_COLON,
+    JTOK_COMMA,
+    JTOK_KW_NULL,
+    JTOK_KW_TRUE,
+    JTOK_KW_FALSE,
+    JTOK_NUMBER,
+    JTOK_STRING,
+};
+
+extern enum jtokentype getJsonToken(std::string& tokenVal,
+                                    unsigned int& consumed, const char *raw);
+extern const char *uvTypeName(UniValue::VType t);
+
+#endif // __UNIVALUE_H__
diff --git a/src/univalue/univalue_read.cpp b/src/univalue/univalue_read.cpp
new file mode 100644
index 0000000000..405be3e81f
--- /dev/null
+++ b/src/univalue/univalue_read.cpp
@@ -0,0 +1,390 @@
+// Copyright 2014 BitPay Inc.
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <string.h>
+#include <vector>
+#include <stdio.h>
+#include "univalue.h"
+
+using namespace std;
+
+// convert hexadecimal string to unsigned integer
+static const char *hatoui(const char *first, const char *last,
+                          unsigned int& out)
+{
+    unsigned int result = 0;
+    for (; first != last; ++first)
+    {
+        int digit;
+        if (isdigit(*first))
+            digit = *first - '0';
+
+        else if (*first >= 'a' && *first <= 'f')
+            digit = *first - 'a' + 10;
+
+        else if (*first >= 'A' && *first <= 'F')
+            digit = *first - 'A' + 10;
+
+        else
+            break;
+
+        result = 16 * result + digit;
+    }
+    out = result;
+
+    return first;
+}
+
+enum jtokentype getJsonToken(string& tokenVal, unsigned int& consumed,
+                            const char *raw)
+{
+    tokenVal.clear();
+    consumed = 0;
+
+    const char *rawStart = raw;
+
+    while ((*raw) && (isspace(*raw)))             // skip whitespace
+        raw++;
+
+    switch (*raw) {
+
+    case 0:
+        return JTOK_NONE;
+
+    case '{':
+        raw++;
+        consumed = (raw - rawStart);
+        return JTOK_OBJ_OPEN;
+    case '}':
+        raw++;
+        consumed = (raw - rawStart);
+        return JTOK_OBJ_CLOSE;
+    case '[':
+        raw++;
+        consumed = (raw - rawStart);
+        return JTOK_ARR_OPEN;
+    case ']':
+        raw++;
+        consumed = (raw - rawStart);
+        return JTOK_ARR_CLOSE;
+
+    case ':':
+        raw++;
+        consumed = (raw - rawStart);
+        return JTOK_COLON;
+    case ',':
+        raw++;
+        consumed = (raw - rawStart);
+        return JTOK_COMMA;
+
+    case 'n':
+    case 't':
+    case 'f':
+        if (!strncmp(raw, "null", 4)) {
+            raw += 4;
+            consumed = (raw - rawStart);
+            return JTOK_KW_NULL;
+        } else if (!strncmp(raw, "true", 4)) {
+            raw += 4;
+            consumed = (raw - rawStart);
+            return JTOK_KW_TRUE;
+        } else if (!strncmp(raw, "false", 5)) {
+            raw += 5;
+            consumed = (raw - rawStart);
+            return JTOK_KW_FALSE;
+        } else
+            return JTOK_ERR;
+
+    case '-':
+    case '0':
+    case '1':
+    case '2':
+    case '3':
+    case '4':
+    case '5':
+    case '6':
+    case '7':
+    case '8':
+    case '9': {
+        // part 1: int
+        string numStr;
+
+        const char *first = raw;
+
+        const char *firstDigit = first;
+        if (!isdigit(*firstDigit))
+            firstDigit++;
+        if ((*firstDigit == '0') && isdigit(firstDigit[1]))
+            return JTOK_ERR;
+
+        numStr += *raw;                       // copy first char
+        raw++;
+
+        if ((*first == '-') && (!isdigit(*raw)))
+            return JTOK_ERR;
+
+        while ((*raw) && isdigit(*raw)) {     // copy digits
+            numStr += *raw;
+            raw++;
+        }
+
+        // part 2: frac
+        if (*raw == '.') {
+            numStr += *raw;                   // copy .
+            raw++;
+
+            if (!isdigit(*raw))
+                return JTOK_ERR;
+            while ((*raw) && isdigit(*raw)) { // copy digits
+                numStr += *raw;
+                raw++;
+            }
+        }
+
+        // part 3: exp
+        if (*raw == 'e' || *raw == 'E') {
+            numStr += *raw;                   // copy E
+            raw++;
+
+            if (*raw == '-' || *raw == '+') { // copy +/-
+                numStr += *raw;
+                raw++;
+            }
+
+            if (!isdigit(*raw))
+                return JTOK_ERR;
+            while ((*raw) && isdigit(*raw)) { // copy digits
+                numStr += *raw;
+                raw++;
+            }
+        }
+
+        tokenVal = numStr;
+        consumed = (raw - rawStart);
+        return JTOK_NUMBER;
+        }
+
+    case '"': {
+        raw++;                                // skip "
+
+        string valStr;
+
+        while (*raw) {
+            if (*raw < 0x20)
+                return JTOK_ERR;
+
+            else if (*raw == '\\') {
+                raw++;                        // skip backslash
+
+                switch (*raw) {
+                case '"':  valStr += "\""; break;
+                case '\\': valStr += "\\"; break;
+                case '/':  valStr += "/"; break;
+                case 'b':  valStr += "\b"; break;
+                case 'f':  valStr += "\f"; break;
+                case 'n':  valStr += "\n"; break;
+                case 'r':  valStr += "\r"; break;
+                case 't':  valStr += "\t"; break;
+
+                case 'u': {
+                    char buf[4] = {0,0,0,0};
+                    char *last = &buf[0];
+                    unsigned int codepoint;
+                    if (hatoui(raw + 1, raw + 1 + 4, codepoint) !=
+                               raw + 1 + 4)
+                        return JTOK_ERR;
+
+                    if (codepoint <= 0x7f)
+                         *last = (char)codepoint;
+                    else if (codepoint <= 0x7FF) {
+                        *last++ = (char)(0xC0 | (codepoint >> 6));
+                        *last = (char)(0x80 | (codepoint & 0x3F));
+                    } else if (codepoint <= 0xFFFF) {
+                        *last++ = (char)(0xE0 | (codepoint >> 12));
+                        *last++ = (char)(0x80 | ((codepoint >> 6) & 0x3F));
+                        *last = (char)(0x80 | (codepoint & 0x3F));
+                    }
+
+                    valStr += buf;
+                    raw += 4;
+                    break;
+                    }
+                default:
+                    return JTOK_ERR;
+
+                }
+
+                raw++;                        // skip esc'd char
+            }
+
+            else if (*raw == '"') {
+                raw++;                        // skip "
+                break;                        // stop scanning
+            }
+
+            else {
+                valStr += *raw;
+                raw++;
+            }
+        }
+
+        tokenVal = valStr;
+        consumed = (raw - rawStart);
+        return JTOK_STRING;
+        }
+
+    default:
+        return JTOK_ERR;
+    }
+}
+
+bool UniValue::read(const char *raw)
+{
+    clear();
+
+    bool expectName = false;
+    bool expectColon = false;
+    vector<UniValue*> stack;
+
+    enum jtokentype tok = JTOK_NONE;
+    enum jtokentype last_tok = JTOK_NONE;
+    while (1) {
+        last_tok = tok;
+
+        string tokenVal;
+        unsigned int consumed;
+        tok = getJsonToken(tokenVal, consumed, raw);
+        if (tok == JTOK_NONE || tok == JTOK_ERR)
+            break;
+        raw += consumed;
+
+        switch (tok) {
+
+        case JTOK_OBJ_OPEN:
+        case JTOK_ARR_OPEN: {
+            VType utyp = (tok == JTOK_OBJ_OPEN ? VOBJ : VARR);
+            if (!stack.size()) {
+                if (utyp == VOBJ)
+                    setObject();
+                else
+                    setArray();
+                stack.push_back(this);
+            } else {
+                UniValue tmpVal(utyp);
+                UniValue *top = stack.back();
+                top->values.push_back(tmpVal);
+
+                UniValue *newTop = &(top->values.back());
+                stack.push_back(newTop);
+            }
+
+            if (utyp == VOBJ)
+                expectName = true;
+            break;
+            }
+
+        case JTOK_OBJ_CLOSE:
+        case JTOK_ARR_CLOSE: {
+            if (!stack.size() || expectColon || (last_tok == JTOK_COMMA))
+                return false;
+
+            VType utyp = (tok == JTOK_OBJ_CLOSE ? VOBJ : VARR);
+            UniValue *top = stack.back();
+            if (utyp != top->getType())
+                return false;
+
+            stack.pop_back();
+            expectName = false;
+            break;
+            }
+
+        case JTOK_COLON: {
+            if (!stack.size() || expectName || !expectColon)
+                return false;
+
+            UniValue *top = stack.back();
+            if (top->getType() != VOBJ)
+                return false;
+
+            expectColon = false;
+            break;
+            }
+
+        case JTOK_COMMA: {
+            if (!stack.size() || expectName || expectColon ||
+                (last_tok == JTOK_COMMA) || (last_tok == JTOK_ARR_OPEN))
+                return false;
+
+            UniValue *top = stack.back();
+            if (top->getType() == VOBJ)
+                expectName = true;
+            break;
+            }
+
+        case JTOK_KW_NULL:
+        case JTOK_KW_TRUE:
+        case JTOK_KW_FALSE: {
+            if (!stack.size() || expectName || expectColon)
+                return false;
+
+            UniValue tmpVal;
+            switch (tok) {
+            case JTOK_KW_NULL:
+                // do nothing more
+                break;
+            case JTOK_KW_TRUE:
+                tmpVal.setBool(true);
+                break;
+            case JTOK_KW_FALSE:
+                tmpVal.setBool(false);
+                break;
+            default: /* impossible */ break;
+            }
+
+            UniValue *top = stack.back();
+            top->values.push_back(tmpVal);
+
+            break;
+            }
+
+        case JTOK_NUMBER: {
+            if (!stack.size() || expectName || expectColon)
+                return false;
+
+            UniValue tmpVal(VNUM, tokenVal);
+            UniValue *top = stack.back();
+            top->values.push_back(tmpVal);
+
+            break;
+            }
+
+        case JTOK_STRING: {
+            if (!stack.size())
+                return false;
+
+            UniValue *top = stack.back();
+
+            if (expectName) {
+                top->keys.push_back(tokenVal);
+                expectName = false;
+                expectColon = true;
+            } else {
+                UniValue tmpVal(VSTR, tokenVal);
+                top->values.push_back(tmpVal);
+            }
+
+            break;
+            }
+
+        default:
+            return false;
+        }
+    }
+
+    if (stack.size() != 0)
+        return false;
+
+    return true;
+}
+
diff --git a/src/univalue/univalue_write.cpp b/src/univalue/univalue_write.cpp
new file mode 100644
index 0000000000..1818f5c6f9
--- /dev/null
+++ b/src/univalue/univalue_write.cpp
@@ -0,0 +1,145 @@
+// Copyright 2014 BitPay Inc.
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <ctype.h>
+#include <stdio.h>
+#include "univalue.h"
+
+// TODO: Using UTF8
+
+using namespace std;
+
+static bool initEscapes;
+static const char *escapes[256];
+
+static void initJsonEscape()
+{
+    escapes['"'] = "\\\"";
+    escapes['\\'] = "\\\\";
+    escapes['/'] = "\\/";
+    escapes['\b'] = "\\b";
+    escapes['\f'] = "\\f";
+    escapes['\n'] = "\\n";
+    escapes['\r'] = "\\r";
+    escapes['\t'] = "\\t";
+
+    initEscapes = true;
+}
+
+static string json_escape(const string& inS)
+{
+    if (!initEscapes)
+        initJsonEscape();
+
+    string outS;
+    outS.reserve(inS.size() * 2);
+
+    for (unsigned int i = 0; i < inS.size(); i++) {
+        unsigned char ch = inS[i];
+        const char *escStr = escapes[ch];
+
+        if (escStr)
+            outS += escStr;
+
+        else if (isprint(ch))
+            outS += ch;
+
+        else {
+            char tmpesc[16];
+            sprintf(tmpesc, "\\u%04x", ch);
+            outS += tmpesc;
+        }
+    }
+
+    return outS;
+}
+
+string UniValue::write(unsigned int prettyIndent,
+                       unsigned int indentLevel) const
+{
+    string s;
+    s.reserve(1024);
+
+    unsigned int modIndent = indentLevel;
+    if (modIndent == 0)
+        modIndent = 1;
+
+    switch (typ) {
+    case VNULL:
+        s += "null";
+        break;
+    case VOBJ:
+        writeObject(prettyIndent, modIndent, s);
+        break;
+    case VARR:
+        writeArray(prettyIndent, modIndent, s);
+        break;
+    case VSTR:
+        s += "\"" + json_escape(val) + "\"";
+        break;
+    case VNUM:
+        s += val;
+        break;
+    case VBOOL:
+        s += (val == "1" ? "true" : "false");
+        break;
+    }
+
+    return s;
+}
+
+static string spaceStr;
+
+static string indentStr(unsigned int prettyIndent, unsigned int indentLevel)
+{
+    unsigned int spaces = prettyIndent * indentLevel;
+    while (spaceStr.size() < spaces)
+        spaceStr += "                ";
+
+    return spaceStr.substr(0, spaces);
+}
+
+void UniValue::writeArray(unsigned int prettyIndent, unsigned int indentLevel, string& s) const
+{
+    s += "[";
+    if (prettyIndent)
+        s += "\n";
+
+    for (unsigned int i = 0; i < values.size(); i++) {
+        if (prettyIndent)
+            s += indentStr(prettyIndent, indentLevel);
+        s += values[i].write(prettyIndent, indentLevel + 1);
+        if (i != (values.size() - 1))
+            s += ", ";
+        if (prettyIndent)
+            s += "\n";
+    }
+
+    if (prettyIndent)
+        s += indentStr(prettyIndent, indentLevel - 1);
+    s += "]";
+}
+
+void UniValue::writeObject(unsigned int prettyIndent, unsigned int indentLevel, string& s) const
+{
+    s += "{";
+    if (prettyIndent)
+        s += "\n";
+
+    for (unsigned int i = 0; i < keys.size(); i++) {
+        if (prettyIndent)
+            s += indentStr(prettyIndent, indentLevel);
+        s += "\"" + json_escape(keys[i]) + "\": ";
+        s += values[i].write(prettyIndent, indentLevel + 1);
+        if (i != (values.size() - 1))
+            s += ",";
+        if (prettyIndent)
+            s += "\n";
+    }
+
+    if (prettyIndent)
+        s += indentStr(prettyIndent, indentLevel - 1);
+    s += "}";
+}
+