diff options
author | Luke Shumaker <lukeshu@sbcglobal.net> | 2016-06-01 15:52:09 -0400 |
---|---|---|
committer | Luke Shumaker <lukeshu@sbcglobal.net> | 2016-06-01 15:52:09 -0400 |
commit | bb110bc7433adeb79b4814ef2a1c04e2160be396 (patch) | |
tree | c45048907133b8bbd7e2d86b350436a9ad0ffe8b /src/libbasic/utf8.c | |
parent | 192d82912f055a2b4a2b5c02f0ef69b002322bba (diff) |
./move.sh
Diffstat (limited to 'src/libbasic/utf8.c')
-rw-r--r-- | src/libbasic/utf8.c | 409 |
1 files changed, 409 insertions, 0 deletions
diff --git a/src/libbasic/utf8.c b/src/libbasic/utf8.c new file mode 100644 index 0000000000..629db123cd --- /dev/null +++ b/src/libbasic/utf8.c @@ -0,0 +1,409 @@ +/*** + This file is part of systemd. + + Copyright 2008-2011 Kay Sievers + Copyright 2012 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +/* Parts of this file are based on the GLIB utf8 validation functions. The + * original license text follows. */ + +/* gutf8.c - Operations on UTF-8 strings. + * + * Copyright (C) 1999 Tom Tromey + * Copyright (C) 2000 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Library General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library 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 + * Library General Public License for more details. + * + * You should have received a copy of the GNU Library General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <errno.h> +#include <stdbool.h> +#include <stdlib.h> +#include <string.h> + +#include "alloc-util.h" +#include "hexdecoct.h" +#include "macro.h" +#include "utf8.h" + +bool unichar_is_valid(char32_t ch) { + + if (ch >= 0x110000) /* End of unicode space */ + return false; + if ((ch & 0xFFFFF800) == 0xD800) /* Reserved area for UTF-16 */ + return false; + if ((ch >= 0xFDD0) && (ch <= 0xFDEF)) /* Reserved */ + return false; + if ((ch & 0xFFFE) == 0xFFFE) /* BOM (Byte Order Mark) */ + return false; + + return true; +} + +static bool unichar_is_control(char32_t ch) { + + /* + 0 to ' '-1 is the C0 range. + DEL=0x7F, and DEL+1 to 0x9F is C1 range. + '\t' is in C0 range, but more or less harmless and commonly used. + */ + + return (ch < ' ' && ch != '\t' && ch != '\n') || + (0x7F <= ch && ch <= 0x9F); +} + +/* count of characters used to encode one unicode char */ +static int utf8_encoded_expected_len(const char *str) { + unsigned char c; + + assert(str); + + c = (unsigned char) str[0]; + if (c < 0x80) + return 1; + if ((c & 0xe0) == 0xc0) + return 2; + if ((c & 0xf0) == 0xe0) + return 3; + if ((c & 0xf8) == 0xf0) + return 4; + if ((c & 0xfc) == 0xf8) + return 5; + if ((c & 0xfe) == 0xfc) + return 6; + + return 0; +} + +/* decode one unicode char */ +int utf8_encoded_to_unichar(const char *str, char32_t *ret_unichar) { + char32_t unichar; + int len, i; + + assert(str); + + len = utf8_encoded_expected_len(str); + + switch (len) { + case 1: + *ret_unichar = (char32_t)str[0]; + return 0; + case 2: + unichar = str[0] & 0x1f; + break; + case 3: + unichar = (char32_t)str[0] & 0x0f; + break; + case 4: + unichar = (char32_t)str[0] & 0x07; + break; + case 5: + unichar = (char32_t)str[0] & 0x03; + break; + case 6: + unichar = (char32_t)str[0] & 0x01; + break; + default: + return -EINVAL; + } + + for (i = 1; i < len; i++) { + if (((char32_t)str[i] & 0xc0) != 0x80) + return -EINVAL; + unichar <<= 6; + unichar |= (char32_t)str[i] & 0x3f; + } + + *ret_unichar = unichar; + + return 0; +} + +bool utf8_is_printable_newline(const char* str, size_t length, bool newline) { + const char *p; + + assert(str); + + for (p = str; length;) { + int encoded_len, r; + char32_t val; + + encoded_len = utf8_encoded_valid_unichar(p); + if (encoded_len < 0 || + (size_t) encoded_len > length) + return false; + + r = utf8_encoded_to_unichar(p, &val); + if (r < 0 || + unichar_is_control(val) || + (!newline && val == '\n')) + return false; + + length -= encoded_len; + p += encoded_len; + } + + return true; +} + +const char *utf8_is_valid(const char *str) { + const uint8_t *p; + + assert(str); + + for (p = (const uint8_t*) str; *p; ) { + int len; + + len = utf8_encoded_valid_unichar((const char *)p); + if (len < 0) + return NULL; + + p += len; + } + + return str; +} + +char *utf8_escape_invalid(const char *str) { + char *p, *s; + + assert(str); + + p = s = malloc(strlen(str) * 4 + 1); + if (!p) + return NULL; + + while (*str) { + int len; + + len = utf8_encoded_valid_unichar(str); + if (len > 0) { + s = mempcpy(s, str, len); + str += len; + } else { + s = stpcpy(s, UTF8_REPLACEMENT_CHARACTER); + str += 1; + } + } + + *s = '\0'; + + return p; +} + +char *utf8_escape_non_printable(const char *str) { + char *p, *s; + + assert(str); + + p = s = malloc(strlen(str) * 4 + 1); + if (!p) + return NULL; + + while (*str) { + int len; + + len = utf8_encoded_valid_unichar(str); + if (len > 0) { + if (utf8_is_printable(str, len)) { + s = mempcpy(s, str, len); + str += len; + } else { + while (len > 0) { + *(s++) = '\\'; + *(s++) = 'x'; + *(s++) = hexchar((int) *str >> 4); + *(s++) = hexchar((int) *str); + + str += 1; + len --; + } + } + } else { + s = stpcpy(s, UTF8_REPLACEMENT_CHARACTER); + str += 1; + } + } + + *s = '\0'; + + return p; +} + +char *ascii_is_valid(const char *str) { + const char *p; + + assert(str); + + for (p = str; *p; p++) + if ((unsigned char) *p >= 128) + return NULL; + + return (char*) str; +} + +/** + * utf8_encode_unichar() - Encode single UCS-4 character as UTF-8 + * @out_utf8: output buffer of at least 4 bytes or NULL + * @g: UCS-4 character to encode + * + * This encodes a single UCS-4 character as UTF-8 and writes it into @out_utf8. + * The length of the character is returned. It is not zero-terminated! If the + * output buffer is NULL, only the length is returned. + * + * Returns: The length in bytes that the UTF-8 representation does or would + * occupy. + */ +size_t utf8_encode_unichar(char *out_utf8, char32_t g) { + + if (g < (1 << 7)) { + if (out_utf8) + out_utf8[0] = g & 0x7f; + return 1; + } else if (g < (1 << 11)) { + if (out_utf8) { + out_utf8[0] = 0xc0 | ((g >> 6) & 0x1f); + out_utf8[1] = 0x80 | (g & 0x3f); + } + return 2; + } else if (g < (1 << 16)) { + if (out_utf8) { + out_utf8[0] = 0xe0 | ((g >> 12) & 0x0f); + out_utf8[1] = 0x80 | ((g >> 6) & 0x3f); + out_utf8[2] = 0x80 | (g & 0x3f); + } + return 3; + } else if (g < (1 << 21)) { + if (out_utf8) { + out_utf8[0] = 0xf0 | ((g >> 18) & 0x07); + out_utf8[1] = 0x80 | ((g >> 12) & 0x3f); + out_utf8[2] = 0x80 | ((g >> 6) & 0x3f); + out_utf8[3] = 0x80 | (g & 0x3f); + } + return 4; + } + + return 0; +} + +char *utf16_to_utf8(const void *s, size_t length) { + const uint8_t *f; + char *r, *t; + + r = new(char, (length * 4 + 1) / 2 + 1); + if (!r) + return NULL; + + f = s; + t = r; + + while (f < (const uint8_t*) s + length) { + char16_t w1, w2; + + /* see RFC 2781 section 2.2 */ + + w1 = f[1] << 8 | f[0]; + f += 2; + + if (!utf16_is_surrogate(w1)) { + t += utf8_encode_unichar(t, w1); + + continue; + } + + if (utf16_is_trailing_surrogate(w1)) + continue; + else if (f >= (const uint8_t*) s + length) + break; + + w2 = f[1] << 8 | f[0]; + f += 2; + + if (!utf16_is_trailing_surrogate(w2)) { + f -= 2; + continue; + } + + t += utf8_encode_unichar(t, utf16_surrogate_pair_to_unichar(w1, w2)); + } + + *t = 0; + return r; +} + +/* expected size used to encode one unicode char */ +static int utf8_unichar_to_encoded_len(char32_t unichar) { + + if (unichar < 0x80) + return 1; + if (unichar < 0x800) + return 2; + if (unichar < 0x10000) + return 3; + if (unichar < 0x200000) + return 4; + if (unichar < 0x4000000) + return 5; + + return 6; +} + +/* validate one encoded unicode char and return its length */ +int utf8_encoded_valid_unichar(const char *str) { + int len, i, r; + char32_t unichar; + + assert(str); + + len = utf8_encoded_expected_len(str); + if (len == 0) + return -EINVAL; + + /* ascii is valid */ + if (len == 1) + return 1; + + /* check if expected encoded chars are available */ + for (i = 0; i < len; i++) + if ((str[i] & 0x80) != 0x80) + return -EINVAL; + + r = utf8_encoded_to_unichar(str, &unichar); + if (r < 0) + return r; + + /* check if encoded length matches encoded value */ + if (utf8_unichar_to_encoded_len(unichar) != len) + return -EINVAL; + + /* check if value has valid range */ + if (!unichar_is_valid(unichar)) + return -EINVAL; + + return len; +} |