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Diffstat (limited to 'src/shared/utf8.c')
| -rw-r--r-- | src/shared/utf8.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/src/shared/utf8.c b/src/shared/utf8.c new file mode 100644 index 000000000..11619dce2 --- /dev/null +++ b/src/shared/utf8.c @@ -0,0 +1,214 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2012 Lennart Poettering + + systemd 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 2 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 + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +/* This file is 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 Lesser 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +#include <errno.h> +#include <stdlib.h> +#include <inttypes.h> +#include <string.h> +#include <stdbool.h> + +#include "utf8.h" + +#define FILTER_CHAR '_' + +static inline bool is_unicode_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 inline bool is_continuation_char(uint8_t ch) { + if ((ch & 0xc0) != 0x80) /* 10xxxxxx */ + return false; + return true; +} + +static inline void merge_continuation_char(uint32_t *u_ch, uint8_t ch) { + *u_ch <<= 6; + *u_ch |= ch & 0x3f; +} + +static char* utf8_validate(const char *str, char *output) { + uint32_t val = 0; + uint32_t min = 0; + const uint8_t *p, *last; + int size; + uint8_t *o; + + assert(str); + + o = (uint8_t*) output; + for (p = (const uint8_t*) str; *p; p++) { + if (*p < 128) { + if (o) + *o = *p; + } else { + last = p; + + if ((*p & 0xe0) == 0xc0) { /* 110xxxxx two-char seq. */ + size = 2; + min = 128; + val = (uint32_t) (*p & 0x1e); + goto ONE_REMAINING; + } else if ((*p & 0xf0) == 0xe0) { /* 1110xxxx three-char seq.*/ + size = 3; + min = (1 << 11); + val = (uint32_t) (*p & 0x0f); + goto TWO_REMAINING; + } else if ((*p & 0xf8) == 0xf0) { /* 11110xxx four-char seq */ + size = 4; + min = (1 << 16); + val = (uint32_t) (*p & 0x07); + } else + goto error; + + p++; + if (!is_continuation_char(*p)) + goto error; + merge_continuation_char(&val, *p); + + TWO_REMAINING: + p++; + if (!is_continuation_char(*p)) + goto error; + merge_continuation_char(&val, *p); + + ONE_REMAINING: + p++; + if (!is_continuation_char(*p)) + goto error; + merge_continuation_char(&val, *p); + + if (val < min) + goto error; + + if (!is_unicode_valid(val)) + goto error; + + if (o) { + memcpy(o, last, (size_t) size); + o += size; + } + + continue; + + error: + if (o) { + *o = FILTER_CHAR; + p = last; /* We retry at the next character */ + } else + goto failure; + } + + if (o) + o++; + } + + if (o) { + *o = '\0'; + return output; + } + + return (char*) str; + +failure: + return NULL; +} + +char* utf8_is_valid (const char *str) { + return utf8_validate(str, NULL); +} + +char* utf8_filter (const char *str) { + char *new_str; + + assert(str); + + new_str = malloc(strlen(str) + 1); + if (!new_str) + return NULL; + + return utf8_validate(str, new_str); +} + +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; +} + +char *ascii_filter(const char *str) { + char *r, *s, *d; + size_t l; + + assert(str); + + l = strlen(str); + r = malloc(l + 1); + if (!r) + return NULL; + + for (s = r, d = r; *s; s++) + if ((unsigned char) *s < 128) + *(d++) = *s; + + *d = 0; + + return r; +} |