srs/trunk/src/kernel/srs_kernel_utility.hpp

/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2013-2017 OSSRS(winlin)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef SRS_KERNEL_UTILITY_HPP
#define SRS_KERNEL_UTILITY_HPP

#include <srs_core.hpp>

#include <string>
#include <vector>

class SrsBuffer;
class SrsBitBuffer;

// compare
#define srs_min(a, b) (((a) < (b))? (a) : (b))
#define srs_max(a, b) (((a) < (b))? (b) : (a))

// read nalu uev.
extern srs_error_t srs_avc_nalu_read_uev(SrsBitBuffer* stream, int32_t& v);
extern srs_error_t srs_avc_nalu_read_bit(SrsBitBuffer* stream, int8_t& v);

// get current system time in ms, use cache to avoid performance problem
extern int64_t srs_get_system_time_ms();
extern int64_t srs_get_system_startup_time_ms();
// the deamon st-thread will update it.
extern int64_t srs_update_system_time_ms();

// dns resolve utility, return the resolved ip address.
extern std::string srs_dns_resolve(std::string host);

// split the host:port to host and port.
// @remark the hostport format in <host[:port]>, where port is optional.
extern void srs_parse_hostport(const std::string& hostport, std::string& host, int& port);

// parse the endpoint to ip and port.
// @remark hostport format in <[ip:]port>, where ip is default to "0.0.0.0".
extern void srs_parse_endpoint(std::string hostport, std::string& ip, int& port);

// parse the int64 value to string.
extern std::string srs_int2str(int64_t value);
// parse the float value to string, precise is 2.
extern std::string srs_float2str(double value);
// convert bool to switch value, true to "on", false to "off".
extern std::string srs_bool2switch(bool v);

// whether system is little endian
extern bool srs_is_little_endian();

// replace old_str to new_str of str
extern std::string srs_string_replace(std::string str, std::string old_str, std::string new_str);
// trim char in trim_chars of str
extern std::string srs_string_trim_end(std::string str, std::string trim_chars);
// trim char in trim_chars of str
extern std::string srs_string_trim_start(std::string str, std::string trim_chars);
// remove char in remove_chars of str
extern std::string srs_string_remove(std::string str, std::string remove_chars);
// whether string end with
extern bool srs_string_ends_with(std::string str, std::string flag);
extern bool srs_string_ends_with(std::string str, std::string flag0, std::string flag1);
extern bool srs_string_ends_with(std::string str, std::string flag0, std::string flag1, std::string flag2);
extern bool srs_string_ends_with(std::string str, std::string flag0, std::string flag1, std::string flag2, std::string flag3);
// whether string starts with
extern bool srs_string_starts_with(std::string str, std::string flag);
extern bool srs_string_starts_with(std::string str, std::string flag0, std::string flag1);
extern bool srs_string_starts_with(std::string str, std::string flag0, std::string flag1, std::string flag2);
extern bool srs_string_starts_with(std::string str, std::string flag0, std::string flag1, std::string flag2, std::string flag3);
// whether string contains with
extern bool srs_string_contains(std::string str, std::string flag);
extern bool srs_string_contains(std::string str, std::string flag0, std::string flag1);
extern bool srs_string_contains(std::string str, std::string flag0, std::string flag1, std::string flag2);
// find the min match in str for flags.
extern std::string srs_string_min_match(std::string str, std::vector<std::string> flags);
// split the string by flag to array.
extern std::vector<std::string> srs_string_split(std::string str, std::string flag);
extern std::vector<std::string> srs_string_split(std::string str, std::vector<std::string> flags);

/**
 * compare the memory in bytes.
 * @return true if completely equal; otherwise, false.
 */
extern bool srs_bytes_equals(void* pa, void* pb, int size);

// create dir recursively
extern srs_error_t srs_create_dir_recursively(std::string dir);

// whether path exists.
extern bool srs_path_exists(std::string path);
// get the dirname of path, for instance, dirname("/live/livestream")="/live"
extern std::string srs_path_dirname(std::string path);
// get the basename of path, for instance, basename("/live/livestream")="livestream"
extern std::string srs_path_basename(std::string path);
// get the filename of path, for instance, filename("livestream.flv")="livestream"
extern std::string srs_path_filename(std::string path);
// get the file extension of path, for instance, filext("live.flv")=".flv"
extern std::string srs_path_filext(std::string path);

/**
 * whether stream starts with the avc NALU in "AnnexB"
 * from ISO_IEC_14496-10-AVC-2003.pdf, page 211.
 * start code must be "N[00] 00 00 01" where N>=0
 * @param pnb_start_code output the size of start code, must >=3.
 *       NULL to ignore.
 */
extern bool srs_avc_startswith_annexb(SrsBuffer* stream, int* pnb_start_code = NULL);

/**
 * whether stream starts with the aac ADTS
 * from ISO_IEC_14496-3-AAC-2001.pdf, page 75, 1.A.2.2 ADTS.
 * start code must be '1111 1111 1111'B, that is 0xFFF
 */
extern bool srs_aac_startswith_adts(SrsBuffer* stream);

/**
 * cacl the crc32 of bytes in buf, for ffmpeg.
 */
extern uint32_t srs_crc32_mpegts(const void* buf, int size);

/**
 * calc the crc32 of bytes in buf by IEEE, for zip.
 */
extern uint32_t srs_crc32_ieee(const void* buf, int size, uint32_t previous = 0);

/**
 * Decode a base64-encoded string.
 *
 * @param out      buffer for decoded data
 * @param in       null-terminated input string
 * @param out_size size in bytes of the out buffer, must be at
 *                 least 3/4 of the length of in
 * @return         number of bytes written, or a negative value in case of
 *                 invalid input
 */
extern int srs_av_base64_decode(uint8_t* out, const char* in, int out_size);

/**
 * Encode data to base64 and null-terminate.
 *
 * @param out      buffer for encoded data
 * @param out_size size in bytes of the out buffer (including the
 *                 null terminator), must be at least AV_BASE64_SIZE(in_size)
 * @param in       input buffer containing the data to encode
 * @param in_size  size in bytes of the in buffer
 * @return         out or NULL in case of error
 */
extern char* srs_av_base64_encode(char* out, int out_size, const uint8_t* in, int in_size);

/**
 * Calculate the output size needed to base64-encode x bytes to a
 * null-terminated string.
 */
#define SRS_AV_BASE64_SIZE(x) (((x)+2) / 3 * 4 + 1)

/**
 * convert hex string to data.
 * for example, p=config='139056E5A0'
 * output hex to data={0x13, 0x90, 0x56, 0xe5, 0xa0}
 */
extern int ff_hex_to_data(uint8_t* data, const char* p);

/**
 * generate the c0 chunk header for msg.
 * @param cache, the cache to write header.
 * @param nb_cache, the size of cache.
 * @return the size of header. 0 if cache not enough.
 */
extern int srs_chunk_header_c0(int perfer_cid, uint32_t timestamp, int32_t payload_length, int8_t message_type, int32_t stream_id, char* cache, int nb_cache);

/**
 * generate the c3 chunk header for msg.
 * @param cache, the cache to write header.
 * @param nb_cache, the size of cache.
 * @return the size of header. 0 if cache not enough.
 */
extern int srs_chunk_header_c3(int perfer_cid, uint32_t timestamp, char* cache, int nb_cache);

#endif