diff options
Diffstat (limited to 'src/univalue/lib/univalue_read.cpp')
| -rw-r--r-- | src/univalue/lib/univalue_read.cpp | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/src/univalue/lib/univalue_read.cpp b/src/univalue/lib/univalue_read.cpp new file mode 100644 index 0000000000..ae75cb462a --- /dev/null +++ b/src/univalue/lib/univalue_read.cpp @@ -0,0 +1,451 @@ +// Copyright 2014 BitPay Inc. +// Distributed under the MIT 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" +#include "univalue_utffilter.h" + +using namespace std; + +static bool json_isdigit(int ch) +{ + return ((ch >= '0') && (ch <= '9')); +} + +// 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 (json_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, const char *end) +{ + tokenVal.clear(); + consumed = 0; + + const char *rawStart = raw; + + while (raw < end && (json_isspace(*raw))) // skip whitespace + raw++; + + if (raw >= end) + return JTOK_NONE; + + switch (*raw) { + + 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 (!json_isdigit(*firstDigit)) + firstDigit++; + if ((*firstDigit == '0') && json_isdigit(firstDigit[1])) + return JTOK_ERR; + + numStr += *raw; // copy first char + raw++; + + if ((*first == '-') && (raw < end) && (!json_isdigit(*raw))) + return JTOK_ERR; + + while (raw < end && json_isdigit(*raw)) { // copy digits + numStr += *raw; + raw++; + } + + // part 2: frac + if (raw < end && *raw == '.') { + numStr += *raw; // copy . + raw++; + + if (raw >= end || !json_isdigit(*raw)) + return JTOK_ERR; + while (raw < end && json_isdigit(*raw)) { // copy digits + numStr += *raw; + raw++; + } + } + + // part 3: exp + if (raw < end && (*raw == 'e' || *raw == 'E')) { + numStr += *raw; // copy E + raw++; + + if (raw < end && (*raw == '-' || *raw == '+')) { // copy +/- + numStr += *raw; + raw++; + } + + if (raw >= end || !json_isdigit(*raw)) + return JTOK_ERR; + while (raw < end && json_isdigit(*raw)) { // copy digits + numStr += *raw; + raw++; + } + } + + tokenVal = numStr; + consumed = (raw - rawStart); + return JTOK_NUMBER; + } + + case '"': { + raw++; // skip " + + string valStr; + JSONUTF8StringFilter writer(valStr); + + while (true) { + if (raw >= end || (unsigned char)*raw < 0x20) + return JTOK_ERR; + + else if (*raw == '\\') { + raw++; // skip backslash + + if (raw >= end) + return JTOK_ERR; + + switch (*raw) { + case '"': writer.push_back('\"'); break; + case '\\': writer.push_back('\\'); break; + case '/': writer.push_back('/'); break; + case 'b': writer.push_back('\b'); break; + case 'f': writer.push_back('\f'); break; + case 'n': writer.push_back('\n'); break; + case 'r': writer.push_back('\r'); break; + case 't': writer.push_back('\t'); break; + + case 'u': { + unsigned int codepoint; + if (raw + 1 + 4 >= end || + hatoui(raw + 1, raw + 1 + 4, codepoint) != + raw + 1 + 4) + return JTOK_ERR; + writer.push_back_u(codepoint); + raw += 4; + break; + } + default: + return JTOK_ERR; + + } + + raw++; // skip esc'd char + } + + else if (*raw == '"') { + raw++; // skip " + break; // stop scanning + } + + else { + writer.push_back(*raw); + raw++; + } + } + + if (!writer.finalize()) + return JTOK_ERR; + tokenVal = valStr; + consumed = (raw - rawStart); + return JTOK_STRING; + } + + default: + return JTOK_ERR; + } +} + +enum expect_bits { + EXP_OBJ_NAME = (1U << 0), + EXP_COLON = (1U << 1), + EXP_ARR_VALUE = (1U << 2), + EXP_VALUE = (1U << 3), + EXP_NOT_VALUE = (1U << 4), +}; + +#define expect(bit) (expectMask & (EXP_##bit)) +#define setExpect(bit) (expectMask |= EXP_##bit) +#define clearExpect(bit) (expectMask &= ~EXP_##bit) + +bool UniValue::read(const char *raw, size_t size) +{ + clear(); + + uint32_t expectMask = 0; + vector<UniValue*> stack; + + string tokenVal; + unsigned int consumed; + enum jtokentype tok = JTOK_NONE; + enum jtokentype last_tok = JTOK_NONE; + const char* end = raw + size; + do { + last_tok = tok; + + tok = getJsonToken(tokenVal, consumed, raw, end); + if (tok == JTOK_NONE || tok == JTOK_ERR) + return false; + raw += consumed; + + bool isValueOpen = jsonTokenIsValue(tok) || + tok == JTOK_OBJ_OPEN || tok == JTOK_ARR_OPEN; + + if (expect(VALUE)) { + if (!isValueOpen) + return false; + clearExpect(VALUE); + + } else if (expect(ARR_VALUE)) { + bool isArrValue = isValueOpen || (tok == JTOK_ARR_CLOSE); + if (!isArrValue) + return false; + + clearExpect(ARR_VALUE); + + } else if (expect(OBJ_NAME)) { + bool isObjName = (tok == JTOK_OBJ_CLOSE || tok == JTOK_STRING); + if (!isObjName) + return false; + + } else if (expect(COLON)) { + if (tok != JTOK_COLON) + return false; + clearExpect(COLON); + + } else if (!expect(COLON) && (tok == JTOK_COLON)) { + return false; + } + + if (expect(NOT_VALUE)) { + if (isValueOpen) + return false; + clearExpect(NOT_VALUE); + } + + 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) + setExpect(OBJ_NAME); + else + setExpect(ARR_VALUE); + break; + } + + case JTOK_OBJ_CLOSE: + case JTOK_ARR_CLOSE: { + if (!stack.size() || (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(); + clearExpect(OBJ_NAME); + setExpect(NOT_VALUE); + break; + } + + case JTOK_COLON: { + if (!stack.size()) + return false; + + UniValue *top = stack.back(); + if (top->getType() != VOBJ) + return false; + + setExpect(VALUE); + break; + } + + case JTOK_COMMA: { + if (!stack.size() || + (last_tok == JTOK_COMMA) || (last_tok == JTOK_ARR_OPEN)) + return false; + + UniValue *top = stack.back(); + if (top->getType() == VOBJ) + setExpect(OBJ_NAME); + else + setExpect(ARR_VALUE); + break; + } + + case JTOK_KW_NULL: + case JTOK_KW_TRUE: + case JTOK_KW_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; + } + + if (!stack.size()) { + *this = tmpVal; + break; + } + + UniValue *top = stack.back(); + top->values.push_back(tmpVal); + + setExpect(NOT_VALUE); + break; + } + + case JTOK_NUMBER: { + UniValue tmpVal(VNUM, tokenVal); + if (!stack.size()) { + *this = tmpVal; + break; + } + + UniValue *top = stack.back(); + top->values.push_back(tmpVal); + + setExpect(NOT_VALUE); + break; + } + + case JTOK_STRING: { + if (expect(OBJ_NAME)) { + UniValue *top = stack.back(); + top->keys.push_back(tokenVal); + clearExpect(OBJ_NAME); + setExpect(COLON); + } else { + UniValue tmpVal(VSTR, tokenVal); + if (!stack.size()) { + *this = tmpVal; + break; + } + UniValue *top = stack.back(); + top->values.push_back(tmpVal); + } + + setExpect(NOT_VALUE); + break; + } + + default: + return false; + } + } while (!stack.empty ()); + + /* Check that nothing follows the initial construct (parsed above). */ + tok = getJsonToken(tokenVal, consumed, raw, end); + if (tok != JTOK_NONE) + return false; + + return true; +} + |