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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:45:59 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:45:59 +0000 |
commit | 19fcec84d8d7d21e796c7624e521b60d28ee21ed (patch) | |
tree | 42d26aa27d1e3f7c0b8bd3fd14e7d7082f5008dc /src/common/utf8.c | |
parent | Initial commit. (diff) | |
download | ceph-19fcec84d8d7d21e796c7624e521b60d28ee21ed.tar.xz ceph-19fcec84d8d7d21e796c7624e521b60d28ee21ed.zip |
Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/common/utf8.c')
-rw-r--r-- | src/common/utf8.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/common/utf8.c b/src/common/utf8.c new file mode 100644 index 000000000..3a05789f6 --- /dev/null +++ b/src/common/utf8.c @@ -0,0 +1,235 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +// vim: ts=8 sw=2 smarttab +/* + * Ceph - scalable distributed file system + * + * Copyright (C) 2011 New Dream Network + * + * This is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License version 2.1, as published by the Free Software + * Foundation. See file COPYING. + * + */ +#include "common/utf8.h" + +#include <string.h> + +/* + * http://www.unicode.org/versions/Unicode6.0.0/ch03.pdf - page 94 + * + * Table 3-7. Well-Formed UTF-8 Byte Sequences + * + * +--------------------+------------+-------------+------------+-------------+ + * | Code Points | First Byte | Second Byte | Third Byte | Fourth Byte | + * +--------------------+------------+-------------+------------+-------------+ + * | U+0000..U+007F | 00..7F | | | | + * +--------------------+------------+-------------+------------+-------------+ + * | U+0080..U+07FF | C2..DF | 80..BF | | | + * +--------------------+------------+-------------+------------+-------------+ + * | U+0800..U+0FFF | E0 | A0..BF | 80..BF | | + * +--------------------+------------+-------------+------------+-------------+ + * | U+1000..U+CFFF | E1..EC | 80..BF | 80..BF | | + * +--------------------+------------+-------------+------------+-------------+ + * | U+D000..U+D7FF | ED | 80..9F | 80..BF | | + * +--------------------+------------+-------------+------------+-------------+ + * | U+E000..U+FFFF | EE..EF | 80..BF | 80..BF | | + * +--------------------+------------+-------------+------------+-------------+ + * | U+10000..U+3FFFF | F0 | 90..BF | 80..BF | 80..BF | + * +--------------------+------------+-------------+------------+-------------+ + * | U+40000..U+FFFFF | F1..F3 | 80..BF | 80..BF | 80..BF | + * +--------------------+------------+-------------+------------+-------------+ + * | U+100000..U+10FFFF | F4 | 80..8F | 80..BF | 80..BF | + * +--------------------+------------+-------------+------------+-------------+ + */ + +static int high_bits_set(int c) +{ + int ret = 0; + while (1) { + if ((c & 0x80) != 0x080) + break; + c <<= 1; + ++ret; + } + return ret; +} + +/* Encode a 31-bit UTF8 code point to 'buf'. + * Assumes buf is of size MAX_UTF8_SZ + * Returns -1 on failure; number of bytes in the encoded value otherwise. + */ +int encode_utf8(unsigned long u, unsigned char *buf) +{ + /* Unroll loop for common code points */ + if (u <= 0x0000007F) { + buf[0] = u; + return 1; + } else if (u <= 0x000007FF) { + buf[0] = 0xC0 | (u >> 6); + buf[1] = 0x80 | (u & 0x3F); + return 2; + } else if (u <= 0x0000FFFF) { + buf[0] = 0xE0 | (u >> 12); + buf[1] = 0x80 | ((u >> 6) & 0x3F); + buf[2] = 0x80 | (u & 0x3F); + return 3; + } else if (u <= 0x001FFFFF) { + buf[0] = 0xF0 | (u >> 18); + buf[1] = 0x80 | ((u >> 12) & 0x3F); + buf[2] = 0x80 | ((u >> 6) & 0x3F); + buf[3] = 0x80 | (u & 0x3F); + return 4; + } else { + /* Rare/illegal code points */ + if (u <= 0x03FFFFFF) { + for (int i = 4; i >= 1; --i) { + buf[i] = 0x80 | (u & 0x3F); + u >>= 6; + } + buf[0] = 0xF8 | u; + return 5; + } else if (u <= 0x7FFFFFFF) { + for (int i = 5; i >= 1; --i) { + buf[i] = 0x80 | (u & 0x3F); + u >>= 6; + } + buf[0] = 0xFC | u; + return 6; + } + return -1; + } +} + +/* + * Decode a UTF8 character from an array of bytes. Return character code. + * Upon error, return INVALID_UTF8_CHAR. + */ +unsigned long decode_utf8(unsigned char *buf, int nbytes) +{ + unsigned long code; + int i, j; + + if (nbytes <= 0) + return INVALID_UTF8_CHAR; + + if (nbytes == 1) { + if (buf[0] >= 0x80) + return INVALID_UTF8_CHAR; + return buf[0]; + } + + i = high_bits_set(buf[0]); + if (i != nbytes) + return INVALID_UTF8_CHAR; + code = buf[0] & (0xff >> i); + for (j = 1; j < nbytes; ++j) { + if ((buf[j] & 0xc0) != 0x80) + return INVALID_UTF8_CHAR; + code = (code << 6) | (buf[j] & 0x3f); + } + + // Check for invalid code points + if (code == 0xFFFE) + return INVALID_UTF8_CHAR; + if (code == 0xFFFF) + return INVALID_UTF8_CHAR; + if (code >= 0xD800 && code <= 0xDFFF) + return INVALID_UTF8_CHAR; + + return code; +} + +int check_utf8(const char *buf, int len) +{ + /* + * "char" is "signed" on x86 but "unsigned" on aarch64 by default. + * Below code depends on signed/unsigned comparisons, define an + * unsigned buffer explicitly to fix the gap. + */ + const unsigned char *bufu = (const unsigned char *)buf; + int err_pos = 1; + + while (len) { + int nbytes; + unsigned char byte1 = bufu[0]; + + /* 00..7F */ + if (byte1 <= 0x7F) { + nbytes = 1; + /* C2..DF, 80..BF */ + } else if (len >= 2 && byte1 >= 0xC2 && byte1 <= 0xDF && + (signed char)bufu[1] <= (signed char)0xBF) { + nbytes = 2; + } else if (len >= 3) { + unsigned char byte2 = bufu[1]; + + /* Is byte2, byte3 between 0x80 ~ 0xBF */ + int byte2_ok = (signed char)byte2 <= (signed char)0xBF; + int byte3_ok = (signed char)bufu[2] <= (signed char)0xBF; + + if (byte2_ok && byte3_ok && + /* E0, A0..BF, 80..BF */ + ((byte1 == 0xE0 && byte2 >= 0xA0) || + /* E1..EC, 80..BF, 80..BF */ + (byte1 >= 0xE1 && byte1 <= 0xEC) || + /* ED, 80..9F, 80..BF */ + (byte1 == 0xED && byte2 <= 0x9F) || + /* EE..EF, 80..BF, 80..BF */ + (byte1 >= 0xEE && byte1 <= 0xEF))) { + nbytes = 3; + } else if (len >= 4) { + /* Is byte4 between 0x80 ~ 0xBF */ + int byte4_ok = (signed char)bufu[3] <= (signed char)0xBF; + + if (byte2_ok && byte3_ok && byte4_ok && + /* F0, 90..BF, 80..BF, 80..BF */ + ((byte1 == 0xF0 && byte2 >= 0x90) || + /* F1..F3, 80..BF, 80..BF, 80..BF */ + (byte1 >= 0xF1 && byte1 <= 0xF3) || + /* F4, 80..8F, 80..BF, 80..BF */ + (byte1 == 0xF4 && byte2 <= 0x8F))) { + nbytes = 4; + } else { + return err_pos; + } + } else { + return err_pos; + } + } else { + return err_pos; + } + + len -= nbytes; + err_pos += nbytes; + bufu += nbytes; + } + + return 0; +} + +int check_utf8_cstr(const char *buf) +{ + return check_utf8(buf, strlen(buf)); +} + +int is_control_character(int c) +{ + return (((c != 0) && (c < 0x20)) || (c == 0x7f)); +} + +int check_for_control_characters(const char *buf, int len) +{ + int i; + for (i = 0; i < len; ++i) { + if (is_control_character((int)(unsigned char)buf[i])) { + return i + 1; + } + } + return 0; +} + +int check_for_control_characters_cstr(const char *buf) +{ + return check_for_control_characters(buf, strlen(buf)); +} |