diff options
Diffstat (limited to 'src/shared/utf8.c')
| -rw-r--r-- | src/shared/utf8.c | 278 |
1 files changed, 122 insertions, 156 deletions
diff --git a/src/shared/utf8.c b/src/shared/utf8.c index 3964e8b1ce..a8e28accd3 100644 --- a/src/shared/utf8.c +++ b/src/shared/utf8.c @@ -3,6 +3,7 @@ /*** 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 @@ -19,7 +20,7 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ -/* This file is based on the GLIB utf8 validation functions. The +/* Parts of this file are based on the GLIB utf8 validation functions. The * original license text follows. */ /* gutf8.c - Operations on UTF-8 strings. @@ -51,8 +52,6 @@ #include "utf8.h" #include "util.h" -#define FILTER_CHAR '_' - static inline bool is_unicode_valid(uint32_t ch) { if (ch >= 0x110000) /* End of unicode space */ @@ -67,17 +66,6 @@ static inline bool is_unicode_valid(uint32_t ch) { 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 bool is_unicode_control(uint32_t ch) { /* @@ -86,170 +74,101 @@ static bool is_unicode_control(uint32_t ch) { '\t' is in C0 range, but more or less harmless and commonly used. */ - return (ch < ' ' && ch != '\t') || + return (ch < ' ' && ch != '\t' && ch != '\n') || (0x7F <= ch && ch <= 0x9F); } -char* utf8_is_printable_n(const char* str, size_t length) { - uint32_t val = 0; - uint32_t min = 0; - const uint8_t *p; - - assert(str); - - for (p = (const uint8_t*) str; length; p++, length--) { - if (*p < 128) { - val = *p; - } else { - if ((*p & 0xe0) == 0xc0) { /* 110xxxxx two-char seq. */ - min = 128; - val = (uint32_t) (*p & 0x1e); - goto ONE_REMAINING; - } else if ((*p & 0xf0) == 0xe0) { /* 1110xxxx three-char seq.*/ - min = (1 << 11); - val = (uint32_t) (*p & 0x0f); - goto TWO_REMAINING; - } else if ((*p & 0xf8) == 0xf0) { /* 11110xxx four-char seq */ - min = (1 << 16); - val = (uint32_t) (*p & 0x07); - } else - goto error; - - p++; - length--; - if (!length || !is_continuation_char(*p)) - goto error; - merge_continuation_char(&val, *p); - - TWO_REMAINING: - p++; - length--; - if (!is_continuation_char(*p)) - goto error; - merge_continuation_char(&val, *p); - - ONE_REMAINING: - p++; - length--; - if (!is_continuation_char(*p)) - goto error; - merge_continuation_char(&val, *p); - - if (val < min) - goto error; - } +/* count of characters used to encode one unicode char */ +static int utf8_encoded_expected_len(const char *str) { + unsigned char 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; +} - if (is_unicode_control(val)) - goto error; +/* decode one unicode char */ +static int utf8_encoded_to_unichar(const char *str) { + int unichar; + int len; + int i; + + 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 -1; } - return (char*) str; + for (i = 1; i < len; i++) { + if (((int)str[i] & 0xc0) != 0x80) + return -1; + unichar <<= 6; + unichar |= (int)str[i] & 0x3f; + } -error: - return NULL; + return unichar; } -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; +bool utf8_is_printable(const char* str, size_t length) { + const uint8_t *p; 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; - } + for (p = (const uint8_t*) str; length; p++) { + int encoded_len = utf8_encoded_valid_unichar((const char *)p); + int32_t val = utf8_encoded_to_unichar((const char*)p); - if (o) - o++; - } + if (encoded_len < 0 || val < 0 || is_unicode_control(val)) + return false; - if (o) { - *o = '\0'; - return output; + length -= encoded_len; } - return (char*) str; - -failure: - return NULL; -} - -char* utf8_is_valid (const char *str) { - return utf8_validate(str, NULL); + return true; } -char* utf8_filter (const char *str) { - char *new_str; +const char *utf8_is_valid(const char *str) { + const uint8_t *p; assert(str); - new_str = malloc(strlen(str) + 1); - if (!new_str) - return NULL; + for (p = (const uint8_t*) str; *p; ) { + int len = utf8_encoded_valid_unichar((const char *)p); - return utf8_validate(str, new_str); + if (len < 0) + return NULL; + + p += len; + } + + return str; } char *ascii_is_valid(const char *str) { @@ -320,3 +239,50 @@ char *utf16_to_utf8(const void *s, size_t length) { 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; + int unichar; + int i; + + len = utf8_encoded_expected_len(str); + if (len == 0) + return -1; + + /* 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 -1; + + unichar = utf8_encoded_to_unichar(str); + + /* check if encoded length matches encoded value */ + if (utf8_unichar_to_encoded_len(unichar) != len) + return -1; + + /* check if value has valid range */ + if (!is_unicode_valid(unichar)) + return -1; + + return len; +} |