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-rw-r--r--utf8.c682
1 files changed, 682 insertions, 0 deletions
diff --git a/utf8.c b/utf8.c
new file mode 100644
index 0000000000..2c27ce0137
--- /dev/null
+++ b/utf8.c
@@ -0,0 +1,682 @@
+#include "git-compat-util.h"
+#include "strbuf.h"
+#include "utf8.h"
+
+/* This code is originally from http://www.cl.cam.ac.uk/~mgk25/ucs/ */
+
+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, sizeof(zero_width)
+ / sizeof(struct interval) - 1))
+ return 0;
+
+ /* binary search in table of double width characters */
+ if (bisearch(ch, double_width, sizeof(double_width)
+ / sizeof(struct interval) - 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);
+}
+
+int is_encoding_utf8(const char *name)
+{
+ if (!name)
+ return 1;
+ if (!strcasecmp(name, "utf-8") || !strcasecmp(name, "utf8"))
+ return 1;
+ return 0;
+}
+
+int same_encoding(const char *src, const char *dst)
+{
+ if (is_encoding_utf8(src) && is_encoding_utf8(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, int *outsz_p)
+{
+ size_t outsz, outalloc;
+ char *out, *outpos;
+ iconv_ibp cp;
+
+ outsz = insz;
+ outalloc = outsz + 1; /* for terminating NUL */
+ out = xmalloc(outalloc);
+ outpos = out;
+ 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 = sofar + 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, int insz,
+ const char *out_encoding, const char *in_encoding,
+ int *outsz)
+{
+ iconv_t conv;
+ char *out;
+
+ if (!in_encoding)
+ return NULL;
+
+ 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, outsz);
+ iconv_close(conv);
+ return out;
+}
+#endif
+
+/*
+ * 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;
+ }
+}
+
+int is_hfs_dotgit(const char *path)
+{
+ ucs_char_t c;
+
+ c = next_hfs_char(&path);
+ if (c != '.')
+ return 0;
+ c = next_hfs_char(&path);
+
+ /*
+ * there's a great deal of other case-folding that occurs
+ * in HFS+, but this is enough to catch anything that will
+ * convert to ".git"
+ */
+ if (c != 'g' && c != 'G')
+ return 0;
+ c = next_hfs_char(&path);
+ if (c != 'i' && c != 'I')
+ return 0;
+ c = next_hfs_char(&path);
+ if (c != 't' && c != 'T')
+ return 0;
+ c = next_hfs_char(&path);
+ if (c && !is_dir_sep(c))
+ return 0;
+
+ return 1;
+}
+
+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);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-01 05:37:54 +0000