rtc_base/string_encode.cc - src - Git at Google

 /*
  *  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/string_encode.h"

 #include <cstdio>

 #include "rtc_base/arraysize.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/string_utils.h"

 namespace rtc {

 /////////////////////////////////////////////////////////////////////////////
 // String Encoding Utilities
 /////////////////////////////////////////////////////////////////////////////

 namespace {
 const char HEX[] = "0123456789abcdef";

 // Convert an unsigned value from 0 to 15 to the hex character equivalent...
 char hex_encode(unsigned char val) {
   RTC_DCHECK_LT(val, 16);
   return (val < 16) ? HEX[val] : '!';
 }

 // ...and vice-versa.
 bool hex_decode(char ch, unsigned char* val) {
   if ((ch >= '0') && (ch <= '9')) {
     *val = ch - '0';
   } else if ((ch >= 'A') && (ch <= 'F')) {
     *val = (ch - 'A') + 10;
   } else if ((ch >= 'a') && (ch <= 'f')) {
     *val = (ch - 'a') + 10;
   } else {
     return false;
   }
   return true;
 }

 // hex_encode, but separate each byte representation with a delimiter.
 // |delimiter| == 0 means no delimiter
 // If the buffer is too short, we return 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;
 }

 }  // namespace

 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 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();
 }

 std::string ToString(const bool b) {
   return b ? "true" : "false";
 }

 std::string ToString(const char* const s) {
   return std::string(s);
 }
 std::string ToString(const std::string s) {
   return s;
 }

 std::string ToString(const short s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%hd", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }
 std::string ToString(const unsigned short s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%hu", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }
 std::string ToString(const int s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%d", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }
 std::string ToString(const unsigned int s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%u", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }
 std::string ToString(const long int s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%ld", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }
 std::string ToString(const unsigned long int s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%lu", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }
 std::string ToString(const long long int s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%lld", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }
 std::string ToString(const unsigned long long int s) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%llu", s);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }

 std::string ToString(const double d) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%g", d);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }

 std::string ToString(const long double d) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%Lg", d);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }

 std::string ToString(const void* const p) {
   char buf[32];
   const int len = std::snprintf(&buf[0], arraysize(buf), "%p", p);
   RTC_DCHECK_LE(len, arraysize(buf));
   return std::string(&buf[0], len);
 }

 bool FromString(const std::string& s, bool* b) {
   if (s == "false") {
     *b = false;
     return true;
   }
   if (s == "true") {
     *b = true;
     return true;
   }
   return false;
 }

 }  // namespace rtc
	/*
	* 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/string_encode.h"

	#include <cstdio>

	#include "rtc_base/arraysize.h"
	#include "rtc_base/checks.h"
	#include "rtc_base/string_utils.h"

	namespace rtc {

	/////////////////////////////////////////////////////////////////////////////
	// String Encoding Utilities
	/////////////////////////////////////////////////////////////////////////////

	namespace {
	const char HEX[] = "0123456789abcdef";

	// Convert an unsigned value from 0 to 15 to the hex character equivalent...
	char hex_encode(unsigned char val) {
	RTC_DCHECK_LT(val, 16);
	return (val < 16) ? HEX[val] : '!';
	}

	// ...and vice-versa.
	bool hex_decode(char ch, unsigned char* val) {
	if ((ch >= '0') && (ch <= '9')) {
	*val = ch - '0';
	} else if ((ch >= 'A') && (ch <= 'F')) {
	*val = (ch - 'A') + 10;
	} else if ((ch >= 'a') && (ch <= 'f')) {
	*val = (ch - 'a') + 10;
	} else {
	return false;
	}
	return true;
	}

	// hex_encode, but separate each byte representation with a delimiter.
	// \|delimiter\| == 0 means no delimiter
	// If the buffer is too short, we return 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;
	}

	} // namespace

	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 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();
	}

	std::string ToString(const bool b) {
	return b ? "true" : "false";
	}

	std::string ToString(const char* const s) {
	return std::string(s);
	}
	std::string ToString(const std::string s) {
	return s;
	}

	std::string ToString(const short s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%hd", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}
	std::string ToString(const unsigned short s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%hu", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}
	std::string ToString(const int s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%d", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}
	std::string ToString(const unsigned int s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%u", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}
	std::string ToString(const long int s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%ld", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}
	std::string ToString(const unsigned long int s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%lu", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}
	std::string ToString(const long long int s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%lld", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}
	std::string ToString(const unsigned long long int s) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%llu", s);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}

	std::string ToString(const double d) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%g", d);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}

	std::string ToString(const long double d) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%Lg", d);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}

	std::string ToString(const void* const p) {
	char buf[32];
	const int len = std::snprintf(&buf[0], arraysize(buf), "%p", p);
	RTC_DCHECK_LE(len, arraysize(buf));
	return std::string(&buf[0], len);
	}

	bool FromString(const std::string& s, bool* b) {
	if (s == "false") {
	*b = false;
	return true;
	}
	if (s == "true") {
	*b = true;
	return true;
	}
	return false;
	}

	} // namespace rtc