diff options
Diffstat (limited to 'utf8.c')
| -rw-r--r-- | utf8.c | 810 |
1 files changed, 810 insertions, 0 deletions
@@ -0,0 +1,810 @@ +#include "git-compat-util.h" +#include "strbuf.h" +#include "utf8.h" + +/* This code is originally from http://www.cl.cam.ac.uk/~mgk25/ucs/ */ + +static const char utf16_be_bom[] = {'\xFE', '\xFF'}; +static const char utf16_le_bom[] = {'\xFF', '\xFE'}; +static const char utf32_be_bom[] = {'\0', '\0', '\xFE', '\xFF'}; +static const char utf32_le_bom[] = {'\xFF', '\xFE', '\0', '\0'}; + +struct interval { + ucs_char_t first; + ucs_char_t last; +}; + +size_t display_mode_esc_sequence_len(const char *s) +{ + const char *p = s; + if (*p++ != '\033') + return 0; + if (*p++ != '[') + return 0; + while (isdigit(*p) || *p == ';') + p++; + if (*p++ != 'm') + return 0; + return p - s; +} + +/* auxiliary function for binary search in interval table */ +static int bisearch(ucs_char_t ucs, const struct interval *table, int max) +{ + int min = 0; + int mid; + + if (ucs < table[0].first || ucs > table[max].last) + return 0; + while (max >= min) { + mid = min + (max - min) / 2; + if (ucs > table[mid].last) + min = mid + 1; + else if (ucs < table[mid].first) + max = mid - 1; + else + return 1; + } + + return 0; +} + +/* The following two functions define the column width of an ISO 10646 + * character as follows: + * + * - The null character (U+0000) has a column width of 0. + * + * - Other C0/C1 control characters and DEL will lead to a return + * value of -1. + * + * - Non-spacing and enclosing combining characters (general + * category code Mn or Me in the Unicode database) have a + * column width of 0. + * + * - SOFT HYPHEN (U+00AD) has a column width of 1. + * + * - Other format characters (general category code Cf in the Unicode + * database) and ZERO WIDTH SPACE (U+200B) have a column width of 0. + * + * - Hangul Jamo medial vowels and final consonants (U+1160-U+11FF) + * have a column width of 0. + * + * - Spacing characters in the East Asian Wide (W) or East Asian + * Full-width (F) category as defined in Unicode Technical + * Report #11 have a column width of 2. + * + * - All remaining characters (including all printable + * ISO 8859-1 and WGL4 characters, Unicode control characters, + * etc.) have a column width of 1. + * + * This implementation assumes that ucs_char_t characters are encoded + * in ISO 10646. + */ + +static int git_wcwidth(ucs_char_t ch) +{ + /* + * Sorted list of non-overlapping intervals of non-spacing characters, + */ +#include "unicode-width.h" + + /* test for 8-bit control characters */ + if (ch == 0) + return 0; + if (ch < 32 || (ch >= 0x7f && ch < 0xa0)) + return -1; + + /* binary search in table of non-spacing characters */ + if (bisearch(ch, zero_width, ARRAY_SIZE(zero_width) - 1)) + return 0; + + /* binary search in table of double width characters */ + if (bisearch(ch, double_width, ARRAY_SIZE(double_width) - 1)) + return 2; + + return 1; +} + +/* + * Pick one ucs character starting from the location *start points at, + * and return it, while updating the *start pointer to point at the + * end of that character. When remainder_p is not NULL, the location + * holds the number of bytes remaining in the string that we are allowed + * to pick from. Otherwise we are allowed to pick up to the NUL that + * would eventually appear in the string. *remainder_p is also reduced + * by the number of bytes we have consumed. + * + * If the string was not a valid UTF-8, *start pointer is set to NULL + * and the return value is undefined. + */ +static ucs_char_t pick_one_utf8_char(const char **start, size_t *remainder_p) +{ + unsigned char *s = (unsigned char *)*start; + ucs_char_t ch; + size_t remainder, incr; + + /* + * A caller that assumes NUL terminated text can choose + * not to bother with the remainder length. We will + * stop at the first NUL. + */ + remainder = (remainder_p ? *remainder_p : 999); + + if (remainder < 1) { + goto invalid; + } else if (*s < 0x80) { + /* 0xxxxxxx */ + ch = *s; + incr = 1; + } else if ((s[0] & 0xe0) == 0xc0) { + /* 110XXXXx 10xxxxxx */ + if (remainder < 2 || + (s[1] & 0xc0) != 0x80 || + (s[0] & 0xfe) == 0xc0) + goto invalid; + ch = ((s[0] & 0x1f) << 6) | (s[1] & 0x3f); + incr = 2; + } else if ((s[0] & 0xf0) == 0xe0) { + /* 1110XXXX 10Xxxxxx 10xxxxxx */ + if (remainder < 3 || + (s[1] & 0xc0) != 0x80 || + (s[2] & 0xc0) != 0x80 || + /* overlong? */ + (s[0] == 0xe0 && (s[1] & 0xe0) == 0x80) || + /* surrogate? */ + (s[0] == 0xed && (s[1] & 0xe0) == 0xa0) || + /* U+FFFE or U+FFFF? */ + (s[0] == 0xef && s[1] == 0xbf && + (s[2] & 0xfe) == 0xbe)) + goto invalid; + ch = ((s[0] & 0x0f) << 12) | + ((s[1] & 0x3f) << 6) | (s[2] & 0x3f); + incr = 3; + } else if ((s[0] & 0xf8) == 0xf0) { + /* 11110XXX 10XXxxxx 10xxxxxx 10xxxxxx */ + if (remainder < 4 || + (s[1] & 0xc0) != 0x80 || + (s[2] & 0xc0) != 0x80 || + (s[3] & 0xc0) != 0x80 || + /* overlong? */ + (s[0] == 0xf0 && (s[1] & 0xf0) == 0x80) || + /* > U+10FFFF? */ + (s[0] == 0xf4 && s[1] > 0x8f) || s[0] > 0xf4) + goto invalid; + ch = ((s[0] & 0x07) << 18) | ((s[1] & 0x3f) << 12) | + ((s[2] & 0x3f) << 6) | (s[3] & 0x3f); + incr = 4; + } else { +invalid: + *start = NULL; + return 0; + } + + *start += incr; + if (remainder_p) + *remainder_p = remainder - incr; + return ch; +} + +/* + * This function returns the number of columns occupied by the character + * pointed to by the variable start. The pointer is updated to point at + * the next character. When remainder_p is not NULL, it points at the + * location that stores the number of remaining bytes we can use to pick + * a character (see pick_one_utf8_char() above). + */ +int utf8_width(const char **start, size_t *remainder_p) +{ + ucs_char_t ch = pick_one_utf8_char(start, remainder_p); + if (!*start) + return 0; + return git_wcwidth(ch); +} + +/* + * Returns the total number of columns required by a null-terminated + * string, assuming that the string is utf8. Returns strlen() instead + * if the string does not look like a valid utf8 string. + */ +int utf8_strnwidth(const char *string, int len, int skip_ansi) +{ + int width = 0; + const char *orig = string; + + if (len == -1) + len = strlen(string); + while (string && string < orig + len) { + int skip; + while (skip_ansi && + (skip = display_mode_esc_sequence_len(string)) != 0) + string += skip; + width += utf8_width(&string, NULL); + } + return string ? width : len; +} + +int utf8_strwidth(const char *string) +{ + return utf8_strnwidth(string, -1, 0); +} + +int is_utf8(const char *text) +{ + while (*text) { + if (*text == '\n' || *text == '\t' || *text == '\r') { + text++; + continue; + } + utf8_width(&text, NULL); + if (!text) + return 0; + } + return 1; +} + +static void strbuf_add_indented_text(struct strbuf *buf, const char *text, + int indent, int indent2) +{ + if (indent < 0) + indent = 0; + while (*text) { + const char *eol = strchrnul(text, '\n'); + if (*eol == '\n') + eol++; + strbuf_addchars(buf, ' ', indent); + strbuf_add(buf, text, eol - text); + text = eol; + indent = indent2; + } +} + +/* + * Wrap the text, if necessary. The variable indent is the indent for the + * first line, indent2 is the indent for all other lines. + * If indent is negative, assume that already -indent columns have been + * consumed (and no extra indent is necessary for the first line). + */ +void strbuf_add_wrapped_text(struct strbuf *buf, + const char *text, int indent1, int indent2, int width) +{ + int indent, w, assume_utf8 = 1; + const char *bol, *space, *start = text; + size_t orig_len = buf->len; + + if (width <= 0) { + strbuf_add_indented_text(buf, text, indent1, indent2); + return; + } + +retry: + bol = text; + w = indent = indent1; + space = NULL; + if (indent < 0) { + w = -indent; + space = text; + } + + for (;;) { + char c; + size_t skip; + + while ((skip = display_mode_esc_sequence_len(text))) + text += skip; + + c = *text; + if (!c || isspace(c)) { + if (w <= width || !space) { + const char *start = bol; + if (!c && text == start) + return; + if (space) + start = space; + else + strbuf_addchars(buf, ' ', indent); + strbuf_add(buf, start, text - start); + if (!c) + return; + space = text; + if (c == '\t') + w |= 0x07; + else if (c == '\n') { + space++; + if (*space == '\n') { + strbuf_addch(buf, '\n'); + goto new_line; + } + else if (!isalnum(*space)) + goto new_line; + else + strbuf_addch(buf, ' '); + } + w++; + text++; + } + else { +new_line: + strbuf_addch(buf, '\n'); + text = bol = space + isspace(*space); + space = NULL; + w = indent = indent2; + } + continue; + } + if (assume_utf8) { + w += utf8_width(&text, NULL); + if (!text) { + assume_utf8 = 0; + text = start; + strbuf_setlen(buf, orig_len); + goto retry; + } + } else { + w++; + text++; + } + } +} + +void strbuf_add_wrapped_bytes(struct strbuf *buf, const char *data, int len, + int indent, int indent2, int width) +{ + char *tmp = xstrndup(data, len); + strbuf_add_wrapped_text(buf, tmp, indent, indent2, width); + free(tmp); +} + +void strbuf_utf8_replace(struct strbuf *sb_src, int pos, int width, + const char *subst) +{ + struct strbuf sb_dst = STRBUF_INIT; + char *src = sb_src->buf; + char *end = src + sb_src->len; + char *dst; + int w = 0, subst_len = 0; + + if (subst) + subst_len = strlen(subst); + strbuf_grow(&sb_dst, sb_src->len + subst_len); + dst = sb_dst.buf; + + while (src < end) { + char *old; + size_t n; + + while ((n = display_mode_esc_sequence_len(src))) { + memcpy(dst, src, n); + src += n; + dst += n; + } + + if (src >= end) + break; + + old = src; + n = utf8_width((const char**)&src, NULL); + if (!src) /* broken utf-8, do nothing */ + goto out; + if (n && w >= pos && w < pos + width) { + if (subst) { + memcpy(dst, subst, subst_len); + dst += subst_len; + subst = NULL; + } + w += n; + continue; + } + memcpy(dst, old, src - old); + dst += src - old; + w += n; + } + strbuf_setlen(&sb_dst, dst - sb_dst.buf); + strbuf_swap(sb_src, &sb_dst); +out: + strbuf_release(&sb_dst); +} + +/* + * Returns true (1) if the src encoding name matches the dst encoding + * name directly or one of its alternative names. E.g. UTF-16BE is the + * same as UTF16BE. + */ +static int same_utf_encoding(const char *src, const char *dst) +{ + if (skip_iprefix(src, "utf", &src) && skip_iprefix(dst, "utf", &dst)) { + skip_prefix(src, "-", &src); + skip_prefix(dst, "-", &dst); + return !strcasecmp(src, dst); + } + return 0; +} + +int is_encoding_utf8(const char *name) +{ + if (!name) + return 1; + if (same_utf_encoding("utf-8", name)) + return 1; + return 0; +} + +int same_encoding(const char *src, const char *dst) +{ + static const char utf8[] = "UTF-8"; + + if (!src) + src = utf8; + if (!dst) + dst = utf8; + if (same_utf_encoding(src, dst)) + return 1; + return !strcasecmp(src, dst); +} + +/* + * Wrapper for fprintf and returns the total number of columns required + * for the printed string, assuming that the string is utf8. + */ +int utf8_fprintf(FILE *stream, const char *format, ...) +{ + struct strbuf buf = STRBUF_INIT; + va_list arg; + int columns; + + va_start(arg, format); + strbuf_vaddf(&buf, format, arg); + va_end(arg); + + columns = fputs(buf.buf, stream); + if (0 <= columns) /* keep the error from the I/O */ + columns = utf8_strwidth(buf.buf); + strbuf_release(&buf); + return columns; +} + +/* + * Given a buffer and its encoding, return it re-encoded + * with iconv. If the conversion fails, returns NULL. + */ +#ifndef NO_ICONV +#if defined(OLD_ICONV) || (defined(__sun__) && !defined(_XPG6)) + typedef const char * iconv_ibp; +#else + typedef char * iconv_ibp; +#endif +char *reencode_string_iconv(const char *in, size_t insz, iconv_t conv, + size_t bom_len, size_t *outsz_p) +{ + size_t outsz, outalloc; + char *out, *outpos; + iconv_ibp cp; + + outsz = insz; + outalloc = st_add(outsz, 1 + bom_len); /* for terminating NUL */ + out = xmalloc(outalloc); + outpos = out + bom_len; + cp = (iconv_ibp)in; + + while (1) { + size_t cnt = iconv(conv, &cp, &insz, &outpos, &outsz); + + if (cnt == (size_t) -1) { + size_t sofar; + if (errno != E2BIG) { + free(out); + return NULL; + } + /* insz has remaining number of bytes. + * since we started outsz the same as insz, + * it is likely that insz is not enough for + * converting the rest. + */ + sofar = outpos - out; + outalloc = st_add3(sofar, st_mult(insz, 2), 32); + out = xrealloc(out, outalloc); + outpos = out + sofar; + outsz = outalloc - sofar - 1; + } + else { + *outpos = '\0'; + if (outsz_p) + *outsz_p = outpos - out; + break; + } + } + return out; +} + +static const char *fallback_encoding(const char *name) +{ + /* + * Some platforms do not have the variously spelled variants of + * UTF-8, so let's fall back to trying the most official + * spelling. We do so only as a fallback in case the platform + * does understand the user's spelling, but not our official + * one. + */ + if (is_encoding_utf8(name)) + return "UTF-8"; + + /* + * Even though latin-1 is still seen in e-mail + * headers, some platforms only install ISO-8859-1. + */ + if (!strcasecmp(name, "latin-1")) + return "ISO-8859-1"; + + return name; +} + +char *reencode_string_len(const char *in, size_t insz, + const char *out_encoding, const char *in_encoding, + size_t *outsz) +{ + iconv_t conv; + char *out; + const char *bom_str = NULL; + size_t bom_len = 0; + + if (!in_encoding) + return NULL; + + /* UTF-16LE-BOM is the same as UTF-16 for reading */ + if (same_utf_encoding("UTF-16LE-BOM", in_encoding)) + in_encoding = "UTF-16"; + + /* + * For writing, UTF-16 iconv typically creates "UTF-16BE-BOM" + * Some users under Windows want the little endian version + * + * We handle UTF-16 and UTF-32 ourselves only if the platform does not + * provide a BOM (which we require), since we want to match the behavior + * of the system tools and libc as much as possible. + */ + if (same_utf_encoding("UTF-16LE-BOM", out_encoding)) { + bom_str = utf16_le_bom; + bom_len = sizeof(utf16_le_bom); + out_encoding = "UTF-16LE"; + } else if (same_utf_encoding("UTF-16BE-BOM", out_encoding)) { + bom_str = utf16_be_bom; + bom_len = sizeof(utf16_be_bom); + out_encoding = "UTF-16BE"; +#ifdef ICONV_OMITS_BOM + } else if (same_utf_encoding("UTF-16", out_encoding)) { + bom_str = utf16_be_bom; + bom_len = sizeof(utf16_be_bom); + out_encoding = "UTF-16BE"; + } else if (same_utf_encoding("UTF-32", out_encoding)) { + bom_str = utf32_be_bom; + bom_len = sizeof(utf32_be_bom); + out_encoding = "UTF-32BE"; +#endif + } + + conv = iconv_open(out_encoding, in_encoding); + if (conv == (iconv_t) -1) { + in_encoding = fallback_encoding(in_encoding); + out_encoding = fallback_encoding(out_encoding); + + conv = iconv_open(out_encoding, in_encoding); + if (conv == (iconv_t) -1) + return NULL; + } + out = reencode_string_iconv(in, insz, conv, bom_len, outsz); + iconv_close(conv); + if (out && bom_str && bom_len) + memcpy(out, bom_str, bom_len); + return out; +} +#endif + +static int has_bom_prefix(const char *data, size_t len, + const char *bom, size_t bom_len) +{ + return data && bom && (len >= bom_len) && !memcmp(data, bom, bom_len); +} + +int has_prohibited_utf_bom(const char *enc, const char *data, size_t len) +{ + return ( + (same_utf_encoding("UTF-16BE", enc) || + same_utf_encoding("UTF-16LE", enc)) && + (has_bom_prefix(data, len, utf16_be_bom, sizeof(utf16_be_bom)) || + has_bom_prefix(data, len, utf16_le_bom, sizeof(utf16_le_bom))) + ) || ( + (same_utf_encoding("UTF-32BE", enc) || + same_utf_encoding("UTF-32LE", enc)) && + (has_bom_prefix(data, len, utf32_be_bom, sizeof(utf32_be_bom)) || + has_bom_prefix(data, len, utf32_le_bom, sizeof(utf32_le_bom))) + ); +} + +int is_missing_required_utf_bom(const char *enc, const char *data, size_t len) +{ + return ( + (same_utf_encoding(enc, "UTF-16")) && + !(has_bom_prefix(data, len, utf16_be_bom, sizeof(utf16_be_bom)) || + has_bom_prefix(data, len, utf16_le_bom, sizeof(utf16_le_bom))) + ) || ( + (same_utf_encoding(enc, "UTF-32")) && + !(has_bom_prefix(data, len, utf32_be_bom, sizeof(utf32_be_bom)) || + has_bom_prefix(data, len, utf32_le_bom, sizeof(utf32_le_bom))) + ); +} + +/* + * Returns first character length in bytes for multi-byte `text` according to + * `encoding`. + * + * - The `text` pointer is updated to point at the next character. + * - When `remainder_p` is not NULL, on entry `*remainder_p` is how much bytes + * we can consume from text, and on exit `*remainder_p` is reduced by returned + * character length. Otherwise `text` is treated as limited by NUL. + */ +int mbs_chrlen(const char **text, size_t *remainder_p, const char *encoding) +{ + int chrlen; + const char *p = *text; + size_t r = (remainder_p ? *remainder_p : SIZE_MAX); + + if (r < 1) + return 0; + + if (is_encoding_utf8(encoding)) { + pick_one_utf8_char(&p, &r); + + chrlen = p ? (p - *text) + : 1 /* not valid UTF-8 -> raw byte sequence */; + } + else { + /* + * TODO use iconv to decode one char and obtain its chrlen + * for now, let's treat encodings != UTF-8 as one-byte + */ + chrlen = 1; + } + + *text += chrlen; + if (remainder_p) + *remainder_p -= chrlen; + + return chrlen; +} + +/* + * Pick the next char from the stream, ignoring codepoints an HFS+ would. + * Note that this is _not_ complete by any means. It's just enough + * to make is_hfs_dotgit() work, and should not be used otherwise. + */ +static ucs_char_t next_hfs_char(const char **in) +{ + while (1) { + ucs_char_t out = pick_one_utf8_char(in, NULL); + /* + * check for malformed utf8. Technically this + * gets converted to a percent-sequence, but + * returning 0 is good enough for is_hfs_dotgit + * to realize it cannot be .git + */ + if (!*in) + return 0; + + /* these code points are ignored completely */ + switch (out) { + case 0x200c: /* ZERO WIDTH NON-JOINER */ + case 0x200d: /* ZERO WIDTH JOINER */ + case 0x200e: /* LEFT-TO-RIGHT MARK */ + case 0x200f: /* RIGHT-TO-LEFT MARK */ + case 0x202a: /* LEFT-TO-RIGHT EMBEDDING */ + case 0x202b: /* RIGHT-TO-LEFT EMBEDDING */ + case 0x202c: /* POP DIRECTIONAL FORMATTING */ + case 0x202d: /* LEFT-TO-RIGHT OVERRIDE */ + case 0x202e: /* RIGHT-TO-LEFT OVERRIDE */ + case 0x206a: /* INHIBIT SYMMETRIC SWAPPING */ + case 0x206b: /* ACTIVATE SYMMETRIC SWAPPING */ + case 0x206c: /* INHIBIT ARABIC FORM SHAPING */ + case 0x206d: /* ACTIVATE ARABIC FORM SHAPING */ + case 0x206e: /* NATIONAL DIGIT SHAPES */ + case 0x206f: /* NOMINAL DIGIT SHAPES */ + case 0xfeff: /* ZERO WIDTH NO-BREAK SPACE */ + continue; + } + + return out; + } +} + +static int is_hfs_dot_generic(const char *path, + const char *needle, size_t needle_len) +{ + ucs_char_t c; + + c = next_hfs_char(&path); + if (c != '.') + return 0; + + /* + * there's a great deal of other case-folding that occurs + * in HFS+, but this is enough to catch our fairly vanilla + * hard-coded needles. + */ + for (; needle_len > 0; needle++, needle_len--) { + c = next_hfs_char(&path); + + /* + * We know our needles contain only ASCII, so we clamp here to + * make the results of tolower() sane. + */ + if (c > 127) + return 0; + if (tolower(c) != *needle) + return 0; + } + + c = next_hfs_char(&path); + if (c && !is_dir_sep(c)) + return 0; + + return 1; +} + +/* + * Inline wrapper to make sure the compiler resolves strlen() on literals at + * compile time. + */ +static inline int is_hfs_dot_str(const char *path, const char *needle) +{ + return is_hfs_dot_generic(path, needle, strlen(needle)); +} + +int is_hfs_dotgit(const char *path) +{ + return is_hfs_dot_str(path, "git"); +} + +int is_hfs_dotgitmodules(const char *path) +{ + return is_hfs_dot_str(path, "gitmodules"); +} + +int is_hfs_dotgitignore(const char *path) +{ + return is_hfs_dot_str(path, "gitignore"); +} + +int is_hfs_dotgitattributes(const char *path) +{ + return is_hfs_dot_str(path, "gitattributes"); +} + +const char utf8_bom[] = "\357\273\277"; + +int skip_utf8_bom(char **text, size_t len) +{ + if (len < strlen(utf8_bom) || + memcmp(*text, utf8_bom, strlen(utf8_bom))) + return 0; + *text += strlen(utf8_bom); + return 1; +} + +void strbuf_utf8_align(struct strbuf *buf, align_type position, unsigned int width, + const char *s) +{ + int slen = strlen(s); + int display_len = utf8_strnwidth(s, slen, 0); + int utf8_compensation = slen - display_len; + + if (display_len >= width) { + strbuf_addstr(buf, s); + return; + } + + if (position == ALIGN_LEFT) + strbuf_addf(buf, "%-*s", width + utf8_compensation, s); + else if (position == ALIGN_MIDDLE) { + int left = (width - display_len) / 2; + strbuf_addf(buf, "%*s%-*s", left, "", width - left + utf8_compensation, s); + } else if (position == ALIGN_RIGHT) + strbuf_addf(buf, "%*s", width + utf8_compensation, s); +} |