blob: f2a1508dcb39281761a480328c6a2e04b140bef6 [file] [log] [blame]
/*
* Copyright 2004 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "rtc_base/stringencode.h"
#include <stdio.h>
#include <stdlib.h>
#include "rtc_base/checks.h"
#include "rtc_base/stringutils.h"
namespace rtc {
/////////////////////////////////////////////////////////////////////////////
// String Encoding Utilities
/////////////////////////////////////////////////////////////////////////////
size_t url_decode(char * buffer, size_t buflen,
const char * source, size_t srclen) {
if (nullptr == buffer)
return srclen + 1;
if (buflen <= 0)
return 0;
unsigned char h1, h2;
size_t srcpos = 0, bufpos = 0;
while ((srcpos < srclen) && (bufpos + 1 < buflen)) {
unsigned char ch = source[srcpos++];
if (ch == '+') {
buffer[bufpos++] = ' ';
} else if ((ch == '%')
&& (srcpos + 1 < srclen)
&& hex_decode(source[srcpos], &h1)
&& hex_decode(source[srcpos+1], &h2))
{
buffer[bufpos++] = (h1 << 4) | h2;
srcpos += 2;
} else {
buffer[bufpos++] = ch;
}
}
buffer[bufpos] = '\0';
return bufpos;
}
size_t utf8_decode(const char* source, size_t srclen, unsigned long* value) {
const unsigned char* s = reinterpret_cast<const unsigned char*>(source);
if ((s[0] & 0x80) == 0x00) { // Check s[0] == 0xxxxxxx
*value = s[0];
return 1;
}
if ((srclen < 2) || ((s[1] & 0xC0) != 0x80)) { // Check s[1] != 10xxxxxx
return 0;
}
// Accumulate the trailer byte values in value16, and combine it with the
// relevant bits from s[0], once we've determined the sequence length.
unsigned long value16 = (s[1] & 0x3F);
if ((s[0] & 0xE0) == 0xC0) { // Check s[0] == 110xxxxx
*value = ((s[0] & 0x1F) << 6) | value16;
return 2;
}
if ((srclen < 3) || ((s[2] & 0xC0) != 0x80)) { // Check s[2] != 10xxxxxx
return 0;
}
value16 = (value16 << 6) | (s[2] & 0x3F);
if ((s[0] & 0xF0) == 0xE0) { // Check s[0] == 1110xxxx
*value = ((s[0] & 0x0F) << 12) | value16;
return 3;
}
if ((srclen < 4) || ((s[3] & 0xC0) != 0x80)) { // Check s[3] != 10xxxxxx
return 0;
}
value16 = (value16 << 6) | (s[3] & 0x3F);
if ((s[0] & 0xF8) == 0xF0) { // Check s[0] == 11110xxx
*value = ((s[0] & 0x07) << 18) | value16;
return 4;
}
return 0;
}
size_t utf8_encode(char* buffer, size_t buflen, unsigned long value) {
if ((value <= 0x7F) && (buflen >= 1)) {
buffer[0] = static_cast<unsigned char>(value);
return 1;
}
if ((value <= 0x7FF) && (buflen >= 2)) {
buffer[0] = 0xC0 | static_cast<unsigned char>(value >> 6);
buffer[1] = 0x80 | static_cast<unsigned char>(value & 0x3F);
return 2;
}
if ((value <= 0xFFFF) && (buflen >= 3)) {
buffer[0] = 0xE0 | static_cast<unsigned char>(value >> 12);
buffer[1] = 0x80 | static_cast<unsigned char>((value >> 6) & 0x3F);
buffer[2] = 0x80 | static_cast<unsigned char>(value & 0x3F);
return 3;
}
if ((value <= 0x1FFFFF) && (buflen >= 4)) {
buffer[0] = 0xF0 | static_cast<unsigned char>(value >> 18);
buffer[1] = 0x80 | static_cast<unsigned char>((value >> 12) & 0x3F);
buffer[2] = 0x80 | static_cast<unsigned char>((value >> 6) & 0x3F);
buffer[3] = 0x80 | static_cast<unsigned char>(value & 0x3F);
return 4;
}
return 0;
}
static const char HEX[] = "0123456789abcdef";
char hex_encode(unsigned char val) {
RTC_DCHECK_LT(val, 16);
return (val < 16) ? HEX[val] : '!';
}
bool hex_decode(char ch, unsigned char* val) {
if ((ch >= '0') && (ch <= '9')) {
*val = ch - '0';
} else if ((ch >= 'A') && (ch <= 'Z')) {
*val = (ch - 'A') + 10;
} else if ((ch >= 'a') && (ch <= 'z')) {
*val = (ch - 'a') + 10;
} else {
return false;
}
return true;
}
size_t hex_encode(char* buffer, size_t buflen,
const char* csource, size_t srclen) {
return hex_encode_with_delimiter(buffer, buflen, csource, srclen, 0);
}
size_t hex_encode_with_delimiter(char* buffer, size_t buflen,
const char* csource, size_t srclen,
char delimiter) {
RTC_DCHECK(buffer); // TODO(kwiberg): estimate output size
if (buflen == 0)
return 0;
// Init and check bounds.
const unsigned char* bsource =
reinterpret_cast<const unsigned char*>(csource);
size_t srcpos = 0, bufpos = 0;
size_t needed = delimiter ? (srclen * 3) : (srclen * 2 + 1);
if (buflen < needed)
return 0;
while (srcpos < srclen) {
unsigned char ch = bsource[srcpos++];
buffer[bufpos ] = hex_encode((ch >> 4) & 0xF);
buffer[bufpos+1] = hex_encode((ch ) & 0xF);
bufpos += 2;
// Don't write a delimiter after the last byte.
if (delimiter && (srcpos < srclen)) {
buffer[bufpos] = delimiter;
++bufpos;
}
}
// Null terminate.
buffer[bufpos] = '\0';
return bufpos;
}
std::string hex_encode(const std::string& str) {
return hex_encode(str.c_str(), str.size());
}
std::string hex_encode(const char* source, size_t srclen) {
return hex_encode_with_delimiter(source, srclen, 0);
}
std::string hex_encode_with_delimiter(const char* source, size_t srclen,
char delimiter) {
const size_t kBufferSize = srclen * 3;
char* buffer = STACK_ARRAY(char, kBufferSize);
size_t length = hex_encode_with_delimiter(buffer, kBufferSize,
source, srclen, delimiter);
RTC_DCHECK(srclen == 0 || length > 0);
return std::string(buffer, length);
}
size_t hex_decode(char * cbuffer, size_t buflen,
const char * source, size_t srclen) {
return hex_decode_with_delimiter(cbuffer, buflen, source, srclen, 0);
}
size_t hex_decode_with_delimiter(char* cbuffer, size_t buflen,
const char* source, size_t srclen,
char delimiter) {
RTC_DCHECK(cbuffer); // TODO(kwiberg): estimate output size
if (buflen == 0)
return 0;
// Init and bounds check.
unsigned char* bbuffer = reinterpret_cast<unsigned char*>(cbuffer);
size_t srcpos = 0, bufpos = 0;
size_t needed = (delimiter) ? (srclen + 1) / 3 : srclen / 2;
if (buflen < needed)
return 0;
while (srcpos < srclen) {
if ((srclen - srcpos) < 2) {
// This means we have an odd number of bytes.
return 0;
}
unsigned char h1, h2;
if (!hex_decode(source[srcpos], &h1) ||
!hex_decode(source[srcpos + 1], &h2))
return 0;
bbuffer[bufpos++] = (h1 << 4) | h2;
srcpos += 2;
// Remove the delimiter if needed.
if (delimiter && (srclen - srcpos) > 1) {
if (source[srcpos] != delimiter)
return 0;
++srcpos;
}
}
return bufpos;
}
size_t hex_decode(char* buffer, size_t buflen, const std::string& source) {
return hex_decode_with_delimiter(buffer, buflen, source, 0);
}
size_t hex_decode_with_delimiter(char* buffer, size_t buflen,
const std::string& source, char delimiter) {
return hex_decode_with_delimiter(buffer, buflen,
source.c_str(), source.length(), delimiter);
}
size_t transform(std::string& value, size_t maxlen, const std::string& source,
Transform t) {
char* buffer = STACK_ARRAY(char, maxlen + 1);
size_t length = t(buffer, maxlen + 1, source.data(), source.length());
value.assign(buffer, length);
return length;
}
std::string s_transform(const std::string& source, Transform t) {
// Ask transformation function to approximate the destination size (returns upper bound)
size_t maxlen = t(nullptr, 0, source.data(), source.length());
char * buffer = STACK_ARRAY(char, maxlen);
size_t len = t(buffer, maxlen, source.data(), source.length());
std::string result(buffer, len);
return result;
}
size_t tokenize(const std::string& source, char delimiter,
std::vector<std::string>* fields) {
fields->clear();
size_t last = 0;
for (size_t i = 0; i < source.length(); ++i) {
if (source[i] == delimiter) {
if (i != last) {
fields->push_back(source.substr(last, i - last));
}
last = i + 1;
}
}
if (last != source.length()) {
fields->push_back(source.substr(last, source.length() - last));
}
return fields->size();
}
size_t tokenize_with_empty_tokens(const std::string& source,
char delimiter,
std::vector<std::string>* fields) {
fields->clear();
size_t last = 0;
for (size_t i = 0; i < source.length(); ++i) {
if (source[i] == delimiter) {
fields->push_back(source.substr(last, i - last));
last = i + 1;
}
}
fields->push_back(source.substr(last, source.length() - last));
return fields->size();
}
size_t tokenize_append(const std::string& source, char delimiter,
std::vector<std::string>* fields) {
if (!fields) return 0;
std::vector<std::string> new_fields;
tokenize(source, delimiter, &new_fields);
fields->insert(fields->end(), new_fields.begin(), new_fields.end());
return fields->size();
}
size_t tokenize(const std::string& source, char delimiter, char start_mark,
char end_mark, std::vector<std::string>* fields) {
if (!fields) return 0;
fields->clear();
std::string remain_source = source;
while (!remain_source.empty()) {
size_t start_pos = remain_source.find(start_mark);
if (std::string::npos == start_pos) break;
std::string pre_mark;
if (start_pos > 0) {
pre_mark = remain_source.substr(0, start_pos - 1);
}
++start_pos;
size_t end_pos = remain_source.find(end_mark, start_pos);
if (std::string::npos == end_pos) break;
// We have found the matching marks. First tokenize the pre-mask. Then add
// the marked part as a single field. Finally, loop back for the post-mark.
tokenize_append(pre_mark, delimiter, fields);
fields->push_back(remain_source.substr(start_pos, end_pos - start_pos));
remain_source = remain_source.substr(end_pos + 1);
}
return tokenize_append(remain_source, delimiter, fields);
}
bool tokenize_first(const std::string& source,
const char delimiter,
std::string* token,
std::string* rest) {
// Find the first delimiter
size_t left_pos = source.find(delimiter);
if (left_pos == std::string::npos) {
return false;
}
// Look for additional occurrances of delimiter.
size_t right_pos = left_pos + 1;
while (source[right_pos] == delimiter) {
right_pos++;
}
*token = source.substr(0, left_pos);
*rest = source.substr(right_pos);
return true;
}
std::string join(const std::vector<std::string>& source, char delimiter) {
if (source.size() == 0) {
return std::string();
}
// Find length of the string to be returned to pre-allocate memory.
size_t source_string_length = 0;
for (size_t i = 0; i < source.size(); ++i) {
source_string_length += source[i].length();
}
// Build the joined string.
std::string joined_string;
joined_string.reserve(source_string_length + source.size() - 1);
for (size_t i = 0; i < source.size(); ++i) {
if (i != 0) {
joined_string += delimiter;
}
joined_string += source[i];
}
return joined_string;
}
size_t split(const std::string& source, char delimiter,
std::vector<std::string>* fields) {
RTC_DCHECK(fields);
fields->clear();
size_t last = 0;
for (size_t i = 0; i < source.length(); ++i) {
if (source[i] == delimiter) {
fields->push_back(source.substr(last, i - last));
last = i + 1;
}
}
fields->push_back(source.substr(last, source.length() - last));
return fields->size();
}
} // namespace rtc