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Diffstat (limited to 'sourcemod/scripting/include/json/decode_helpers.inc')
| -rw-r--r-- | sourcemod/scripting/include/json/decode_helpers.inc | 312 |
1 files changed, 312 insertions, 0 deletions
diff --git a/sourcemod/scripting/include/json/decode_helpers.inc b/sourcemod/scripting/include/json/decode_helpers.inc new file mode 100644 index 0000000..0032cc3 --- /dev/null +++ b/sourcemod/scripting/include/json/decode_helpers.inc @@ -0,0 +1,312 @@ +/** + * vim: set ts=4 : + * ============================================================================= + * sm-json + * Provides a pure SourcePawn implementation of JSON encoding and decoding. + * https://github.com/clugg/sm-json + * + * sm-json (C)2018 James D. (clug) + * SourceMod (C)2004-2008 AlliedModders LLC. All rights reserved. + * ============================================================================= + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License, version 3.0, as published by the + * Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS + * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more + * details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + * + * As a special exception, AlliedModders LLC gives you permission to link the + * code of this program (as well as its derivative works) to "Half-Life 2," the + * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software + * by the Valve Corporation. You must obey the GNU General Public License in + * all respects for all other code used. Additionally, AlliedModders LLC grants + * this exception to all derivative works. AlliedModders LLC defines further + * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007), + * or <http://www.sourcemod.net/license.php>. + */ + +#if defined _json_decode_helpers_included + #endinput +#endif +#define _json_decode_helpers_included + +#include <string> + +/** + * @section Analysing format of incoming JSON cells. + */ + +/** + * Checks whether the character at the given + * position in the buffer is whitespace. + * + * @param buffer String buffer of data. + * @param pos Position to check in buffer. + * @return True if buffer[pos] is whitespace, false otherwise. + */ +stock bool json_is_whitespace(const char[] buffer, int &pos) { + return buffer[pos] == ' ' || buffer[pos] == '\t' || + buffer[pos] == '\r' || buffer[pos] == '\n'; +} + +/** + * Checks whether the character at the beginning + * of the buffer is the start of a string. + * + * @param buffer String buffer of data. + * @return True if buffer[0] is the start of a string, false otherwise. + */ +stock bool json_is_string(const char[] buffer) { + return buffer[0] == '"'; +} + +/** + * Checks whether the buffer provided contains an int. + * + * @param buffer String buffer of data. + * @return True if buffer contains an int, false otherwise. + */ +stock bool json_is_int(const char[] buffer) { + int length = strlen(buffer); + if (buffer[0] != '+' && buffer[0] != '-' && !IsCharNumeric(buffer[0])) { + return false; + } + + for (int i = 0; i < length; ++i) { + if (!IsCharNumeric(buffer[i])) return false; + } + + return true; +} + +/** + * Checks whether the buffer provided contains a float. + * + * @param buffer String buffer of data. + * @return True if buffer contains a float, false otherwise. + */ +stock bool json_is_float(const char[] buffer) { + bool has_decimal = false; + int length = strlen(buffer); + if (buffer[0] != '+' && buffer[0] != '-' && buffer[0] != '.' && !IsCharNumeric(buffer[0])) { + return false; + } + + for (int i = 0; i < length; ++i) { + if (buffer[i] == '.') { + if (has_decimal) { + return false; + } + + has_decimal = true; + } else if (!IsCharNumeric(buffer[i])) { + return false; + } + } + + return true; +} + +/** + * Checks whether the buffer provided contains a bool. + * + * @param buffer String buffer of data. + * @return True if buffer contains a bool, false otherwise. + */ +stock bool json_is_bool(const char[] buffer) { + return StrEqual(buffer, "true") || + StrEqual(buffer, "false"); +} + +/** + * Checks whether the buffer provided contains null. + * + * @param buffer String buffer of data. + * @return True if buffer contains null, false otherwise. + */ +stock bool json_is_null(const char[] buffer) { + return StrEqual(buffer, "null"); +} + +/** + * Checks whether the character at the beginning + * of the buffer is the start of an object. + * + * @param buffer String buffer of data. + * @return True if buffer[0] is the start of an object, false otherwise. + */ +stock bool json_is_object(const char[] buffer) { + return buffer[0] == '{'; +} + +/** + * Checks whether the character at the beginning + * of the buffer is the end of an object. + * + * @param buffer String buffer of data. + * @return True if buffer[0] is the end of an object, false otherwise. + */ +stock bool json_is_object_end(const char[] buffer) { + return buffer[0] == '}'; +} + +/** + * Checks whether the character at the beginning + * of the buffer is the start of an array. + * + * @param buffer String buffer of data. + * @return True if buffer[0] is the start of an array, false otherwise. + */ +stock bool json_is_array(const char[] buffer) { + return buffer[0] == '['; +} + +/** + * Checks whether the character at the beginning + * of the buffer is the start of an array. + * + * @param buffer String buffer of data. + * @return True if buffer[0] is the start of an array, false otherwise. + */ +stock bool json_is_array_end(const char[] buffer) { + return buffer[0] == ']'; +} + +/** + * Checks whether the character at the given position in the buffer + * is considered a valid 'end point' for some data, such as a + * colon (indicating a key), a comma (indicating a new element), + * or the end of an object or array. + * + * @param buffer String buffer of data. + * @param pos Position to check in buffer. + * @return True if buffer[pos] is a valid data end point, false otherwise. + */ +stock bool json_is_at_end(const char[] buffer, int &pos, bool is_array) { + return buffer[pos] == ',' || + (!is_array && buffer[pos] == ':') || + json_is_object_end(buffer[pos]) || + json_is_array_end(buffer[pos]); +} + +/** + * Moves the position until it reaches a non-whitespace + * character or the end of the buffer's maximum size. + * + * @param buffer String buffer of data. + * @param maxlen Maximum size of string buffer. + * @param pos Position to increment. + * @return True if pos is not at the end of the buffer, false otherwise. + */ +stock bool json_skip_whitespace(const char[] buffer, int maxlen, int &pos) { + while (json_is_whitespace(buffer, pos) && pos < maxlen) { + ++pos; + } + + return pos < maxlen; +} + +/** + * Extracts a JSON cell from the buffer until + * a valid end point is reached. + * + * @param buffer String buffer of data. + * @param maxlen Maximum size of string buffer. + * @param pos Position to increment. + * @param output String buffer to store output. + * @param output_maxlen Maximum size of output string buffer. + * @param is_array Whether the decoder is currently processing an array. + * @return True if pos is not at the end of the buffer, false otherwise. + */ +stock bool json_extract_until_end(const char[] buffer, int maxlen, int &pos, char[] output, int output_maxlen, bool is_array) { + // extracts a string from current pos until a valid 'end point' + strcopy(output, output_maxlen, ""); + + int start = pos; + while (!json_is_whitespace(buffer, pos) && !json_is_at_end(buffer, pos, is_array) && pos < maxlen) { + ++pos; + } + int end = pos - 1; + + // skip trailing whitespace + json_skip_whitespace(buffer, maxlen, pos); + + if (!json_is_at_end(buffer, pos, is_array)) return false; + strcopy(output, end - start + 2, buffer[start]); + + return pos < maxlen; +} + + +/** + * Extracts a JSON string from the buffer until + * a valid end point is reached. + * + * @param buffer String buffer of data. + * @param maxlen Maximum size of string buffer. + * @param pos Position to increment. + * @param output String buffer to store output. + * @param output_maxlen Maximum size of output string buffer. + * @param is_array Whether the decoder is currently processing an array. + * @return True if pos is not at the end of the buffer, false otherwise. + */ +stock bool json_extract_string(const char[] buffer, int maxlen, int &pos, char[] output, int output_maxlen, bool is_array) { + // extracts a string which needs to be quote-escaped + strcopy(output, output_maxlen, ""); + + ++pos; + int start = pos; + while (!(buffer[pos] == '"' && buffer[pos - 1] != '\\') && pos < maxlen) { + ++pos; + } + int end = pos - 1; + + // jump 1 ahead since we ended on " instead of an ending char + ++pos; + + // skip trailing whitespace + json_skip_whitespace(buffer, maxlen, pos); + + if (!json_is_at_end(buffer, pos, is_array)) return false; + // copy only from start with length end - start + 2 (+2 for NULL terminator and something else) + strcopy(output, end - start + 2, buffer[start]); + json_unescape_string(output, maxlen); + + return pos < maxlen; +} + +/** + * Extracts an int from the buffer. + * + * @param buffer String buffer of data. + * @return Int value of the buffer. + */ +stock int json_extract_int(const char[] buffer) { + return StringToInt(buffer); +} + +/** + * Extracts a float from the buffer. + * + * @param buffer String buffer of data. + * @return Float value of the buffer. + */ +stock float json_extract_float(const char[] buffer) { + return StringToFloat(buffer); +} + +/** + * Extracts a bool from the buffer. + * + * @param buffer String buffer of data. + * @return Bool value of the buffer. + */ +stock bool json_extract_bool(const char[] buffer) { + return StrEqual(buffer, "true"); +} |