| /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
| |
| /*** |
| 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 <stdlib.h> |
| #include <inttypes.h> |
| #include <string.h> |
| #include <stdbool.h> |
| |
| #include "utf8.h" |
| #include "util.h" |
| |
| bool unichar_is_valid(uint32_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(uint32_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) { |
| int unichar, len, i; |
| |
| assert(str); |
| |
| len = utf8_encoded_expected_len(str); |
| |
| switch (len) { |
| case 1: |
| return (int)str[0]; |
| case 2: |
| unichar = str[0] & 0x1f; |
| break; |
| case 3: |
| unichar = (int)str[0] & 0x0f; |
| break; |
| case 4: |
| unichar = (int)str[0] & 0x07; |
| break; |
| case 5: |
| unichar = (int)str[0] & 0x03; |
| break; |
| case 6: |
| unichar = (int)str[0] & 0x01; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| for (i = 1; i < len; i++) { |
| if (((int)str[i] & 0xc0) != 0x80) |
| return -EINVAL; |
| unichar <<= 6; |
| unichar |= (int)str[i] & 0x3f; |
| } |
| |
| return unichar; |
| } |
| |
| 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, val; |
| |
| encoded_len = utf8_encoded_valid_unichar(p); |
| if (encoded_len < 0 || |
| (size_t) encoded_len > length) |
| return false; |
| |
| val = utf8_encoded_to_unichar(p); |
| if (val < 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, uint32_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) { |
| uint16_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(int 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, unichar, i; |
| |
| 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; |
| |
| unichar = utf8_encoded_to_unichar(str); |
| |
| /* 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; |
| } |