#ifndef _BASE16384_H_
#define _BASE16384_H_
/* base16384.h
* This file is part of the base16384 distribution (https://github.com/fumiama/base16384).
* Copyright (c) 2022-2024 Fumiama Minamoto.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* 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 .
*/
#ifndef __cosmopolitan
#include
#include
#endif
enum base16384_err_t {
base16384_err_ok,
base16384_err_get_file_size,
base16384_err_fopen_output_file,
base16384_err_fopen_input_file,
base16384_err_write_file,
base16384_err_open_input_file,
base16384_err_map_input_file,
base16384_err_read_file,
base16384_err_invalid_file_name,
base16384_err_invalid_commandline_parameter,
base16384_err_invalid_decoding_checksum,
};
/**
* @brief return value of base16384_en/decode_file
*/
typedef enum base16384_err_t base16384_err_t;
#define _BASE16384_ENCBUFSZ (BUFSIZ*1024/7*7)
#define _BASE16384_DECBUFSZ (BUFSIZ*1024/8*8)
#define BASE16384_ENCBUFSZ (_BASE16384_ENCBUFSZ+16)
#define BASE16384_DECBUFSZ (_BASE16384_DECBUFSZ+16)
// disable 0xFEFF file header in encode
#define BASE16384_FLAG_NOHEADER (1<<0)
// enable sum check when using stdin or inputsize > _BASE16384_ENCBUFSZ
#define BASE16384_FLAG_SUM_CHECK_ON_REMAIN (1<<1)
// initial sum value used in BASE16384_FLAG_SUM_CHECK_ON_REMAIN
#define BASE16384_SIMPLE_SUM_INIT_VALUE (0x8e29c213)
/**
* @brief calculate the exact encoded size
* @param dlen the data length to encode
* @return the size
*/
static inline int _base16384_encode_len(int dlen) {
int outlen = dlen / 7 * 8;
int offset = dlen % 7;
switch(offset) { // 算上偏移标志字符占用的 2 字节
case 0: break;
case 1: outlen += 4; break;
case 2:
case 3: outlen += 6; break;
case 4:
case 5: outlen += 8; break;
case 6: outlen += 10; break;
default: break;
}
return outlen;
}
/**
* @brief calculate minimum encoding buffer size (16 bits larger than the real encoded size)
* @param dlen the data length to encode
* @return the minimum encoding buffer size
*/
static inline int base16384_encode_len(int dlen) {
return _base16384_encode_len(dlen) + 16; // 冗余的 16 字节用于可能的结尾的 unsafe 覆盖
}
/**
* @brief calculate the exact decoded size
* @param dlen the data length to decode
* @param offset the last char `xx` of the underfilled coding (0x3Dxx) or 0 for the full coding
* @return the size
*/
static inline int _base16384_decode_len(int dlen, int offset) {
int outlen = dlen;
switch(offset) { // 算上偏移标志字符占用的 2 字节
case 0: break;
case 1: outlen -= 4; break;
case 2:
case 3: outlen -= 6; break;
case 4:
case 5: outlen -= 8; break;
case 6: outlen -= 10; break;
default: break;
}
return outlen / 8 * 7 + offset;
}
/**
* @brief calculate minimum decoding buffer size (16 bits larger than the real decoded size)
* @param dlen the data length to decode
* @param offset the last char `xx` of the underfilled coding (0x3Dxx) or 0 for the full coding
* @return the minimum decoding buffer size
*/
static inline int base16384_decode_len(int dlen, int offset) {
return _base16384_decode_len(dlen, offset) + 16; // 多出 16 字节用于 unsafe 循环覆盖
}
/**
* @brief encode data and write result into buf
* @param data data to encode
* @param dlen the data length
* @param buf the output buffer, whose size must greater than `base16384_encode_len`
* @return the total length written
*/
int base16384_encode(const char* data, int dlen, char* buf);
/**
* @brief encode data and write result into buf without considering border condition
* @param data data to encode
* @param dlen the data length
* @param buf the output buffer, whose size must greater than `base16384_encode_len`
* @return the total length written
*/
int base16384_encode_unsafe(const char* data, int dlen, char* buf);
/**
* @brief decode data and write result into buf
* @param data data to decode
* @param dlen the data length
* @param buf the output buffer, whose size must greater than `base16384_decode_len`
* @return the total length written
*/
int base16384_decode(const char* data, int dlen, char* buf);
/**
* @brief decode data and write result into buf without considering border condition
* @param data data to decode
* @param dlen the data length
* @param buf the output buffer, whose size must greater than `base16384_decode_len`
* @return the total length written
*/
int base16384_decode_unsafe(const char* data, int dlen, char* buf);
#define base16384_typed_params(type) type input, type output, char* encbuf, char* decbuf
#define base16384_typed_flag_params(type) base16384_typed_params(type), int flag
/**
* @brief encode input file to output file
* @param input filename or `-` to specify stdin
* @param output filename or `-` to specify stdout
* @param encbuf must be no less than BASE16384_ENCBUFSZ
* @param decbuf must be no less than BASE16384_DECBUFSZ
* @param flag BASE16384_FLAG_xxx value, add multiple flags by `|`
* @return the error code
*/
base16384_err_t base16384_encode_file_detailed(base16384_typed_flag_params(const char*));
/**
* @brief encode input `FILE*` to output `FILE*`
* @param input `FILE*` pointer
* @param output `FILE*` pointer
* @param encbuf must be no less than BASE16384_ENCBUFSZ
* @param decbuf must be no less than BASE16384_DECBUFSZ
* @param flag BASE16384_FLAG_xxx value, add multiple flags by `|`
* @return the error code
*/
base16384_err_t base16384_encode_fp_detailed(base16384_typed_flag_params(FILE*));
/**
* @brief encode input stream to output stream
* @param input file descripter
* @param output file descripter
* @param encbuf must be no less than BASE16384_ENCBUFSZ
* @param decbuf must be no less than BASE16384_DECBUFSZ
* @param flag BASE16384_FLAG_xxx value, add multiple flags by `|`
* @return the error code
*/
base16384_err_t base16384_encode_fd_detailed(base16384_typed_flag_params(int));
/**
* @brief decode input file to output file
* @param input filename or `-` to specify stdin
* @param output filename or `-` to specify stdout
* @param encbuf must be no less than BASE16384_ENCBUFSZ
* @param decbuf must be no less than BASE16384_DECBUFSZ
* @param flag BASE16384_FLAG_xxx value, add multiple flags by `|`
* @return the error code
*/
base16384_err_t base16384_decode_file_detailed(base16384_typed_flag_params(const char*));
/**
* @brief decode input `FILE*` to output `FILE*`
* @param input `FILE*` pointer
* @param output `FILE*` pointer
* @param encbuf must be no less than BASE16384_ENCBUFSZ
* @param decbuf must be no less than BASE16384_DECBUFSZ
* @param flag BASE16384_FLAG_xxx value, add multiple flags by `|`
* @return the error code
*/
base16384_err_t base16384_decode_fp_detailed(base16384_typed_flag_params(FILE*));
/**
* @brief decode input stream to output stream
* @param input file descripter
* @param output file descripter
* @param encbuf must be no less than BASE16384_ENCBUFSZ
* @param decbuf must be no less than BASE16384_DECBUFSZ
* @param flag BASE16384_FLAG_xxx value, add multiple flags by `|`
* @return the error code
*/
base16384_err_t base16384_decode_fd_detailed(base16384_typed_flag_params(int));
#define BASE16384_WRAP_DECL(method, name, type) \
static inline base16384_err_t base16384_##method##_##name(base16384_typed_params(type)) { \
return base16384_##method##_##name##_detailed(input, output, encbuf, decbuf, 0); \
}
BASE16384_WRAP_DECL(encode, file, const char*);
BASE16384_WRAP_DECL(encode, fp, FILE*);
BASE16384_WRAP_DECL(encode, fd, int);
BASE16384_WRAP_DECL(decode, file, const char*);
BASE16384_WRAP_DECL(decode, fp, FILE*);
BASE16384_WRAP_DECL(decode, fd, int);
#undef BASE16384_WRAP_DECL
#undef base16384_typed_flag_params
#undef base16384_typed_params
/**
* @brief call perror on error
* @param err the error
* @return the input parameter `err`
*/
static inline base16384_err_t base16384_perror(base16384_err_t err) {
#define base16384_perror_case(n) case base16384_err_##n: perror("base16384_err_"#n)
if(err) switch(err) {
base16384_perror_case(get_file_size); break;
base16384_perror_case(fopen_output_file); break;
base16384_perror_case(fopen_input_file); break;
base16384_perror_case(write_file); break;
base16384_perror_case(open_input_file); break;
base16384_perror_case(map_input_file); break;
base16384_perror_case(read_file); break;
base16384_perror_case(invalid_file_name); break;
base16384_perror_case(invalid_commandline_parameter); break;
base16384_perror_case(invalid_decoding_checksum); break;
default: perror("base16384"); break;
}
#undef base16384_perror_case
return err;
}
#endif