Add mruby-string-utf8

mrbgems/mruby-string-utf8/mrbgem.rake

+MRuby::Gem::Specification.new('mruby-string-utf8') do |spec|
+  spec.license = 'MIT'
+  spec.author  = 'mruby developers'
+end

mrbgems/mruby-string-utf8/src/string.c

+#include "mruby.h"
+#include "mruby/string.h"
+#include "mruby/range.h"
+#include <ctype.h>
+#include <string.h>
+
+/* TODO: duplicate definition in src/re.h */
+#define REGEXP_CLASS "Regexp"
+
+static size_t utf8len_tab[256] =
+{
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+  1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+  2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+  3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,1,1,
+};
+
+static size_t
+utf8len(unsigned char* p)
+{
+  size_t    len;
+  int    i;
+
+  if (*p == 0)
+    return 0;
+  len = utf8len_tab[*p];
+  for (i = 1; i < len; ++i)
+    if ((p[i] & 0xc0) != 0x80)
+      return 1;
+  return len;
+}
+
+static size_t
+mrb_utf8_strlen(mrb_value str)
+{
+  size_t total = 0;
+  unsigned char* p = (unsigned char*) RSTRING_PTR(str);
+  while (*p) {
+    p += utf8len(p);
+    total++;
+  }
+  return total;
+}
+
+#define RSTRING_LEN_UTF8(s) mrb_utf8_strlen(s)
+
+static mrb_value
+noregexp(mrb_state *mrb, mrb_value self)
+{
+  mrb_raise(mrb, E_NOTIMP_ERROR, "Regexp class not implemented");
+  return mrb_nil_value();
+}
+
+static void
+regexp_check(mrb_state *mrb, mrb_value obj)
+{
+  if (!memcmp(mrb_obj_classname(mrb, obj), REGEXP_CLASS, sizeof(REGEXP_CLASS) - 1)) {
+    noregexp(mrb, obj);
+  }
+}
+
+static inline mrb_int
+mrb_memsearch_qs(const unsigned char *xs, mrb_int m, const unsigned char *ys, mrb_int n)
+{
+  const unsigned char *x = xs, *xe = xs + m;
+  const unsigned char *y = ys;
+  int i, qstable[256];
+
+  /* Preprocessing */
+  for (i = 0; i < 256; ++i)
+    qstable[i] = m + 1;
+  for (; x < xe; ++x)
+    qstable[*x] = xe - x;
+ /* Searching */
+  for (; y + m <= ys + n; y += *(qstable + y[m])) {
+    if (*xs == *y && memcmp(xs, y, m) == 0)
+        return y - ys;
+  }
+  return -1;
+}
+static mrb_int
+mrb_memsearch(const void *x0, mrb_int m, const void *y0, mrb_int n)
+{
+  const unsigned char *x = (const unsigned char *)x0, *y = (const unsigned char *)y0;
+
+  if (m > n) return -1;
+  else if (m == n) {
+    return memcmp(x0, y0, m) == 0 ? 0 : -1;
+  }
+  else if (m < 1) {
+    return 0;
+  }
+ else if (m == 1) {
+    const unsigned char *ys = y, *ye = ys + n;
+    for (; y < ye; ++y) {
+      if (*x == *y)
+        return y - ys;
+    }
+    return -1;
+  }
+  return mrb_memsearch_qs((const unsigned char *)x0, m, (const unsigned char *)y0, n);
+}
+
+static mrb_value
+str_subseq(mrb_state *mrb, mrb_value str, mrb_int beg, mrb_int len)
+{
+  int i;
+  unsigned char  *p = (unsigned char*) RSTRING_PTR(str), *t;
+  for (i = 0; i < beg && *p; i++) {
+    p += utf8len(p);
+  }
+  t = p;
+  for (i = 0; i < len && *p; i++) {
+    t += utf8len(t);
+  }
+  return mrb_str_new(mrb, (const char*)p, (int)(t - p));
+}
+
+static mrb_value
+str_substr(mrb_state *mrb, mrb_value str, mrb_int beg, mrb_int len)
+{
+  mrb_value str2;
+  int len8 = RSTRING_LEN_UTF8(str);
+
+  if (len < 0) return mrb_nil_value();
+  if (len8 == 0) {
+    len = 0;
+  } else if (beg < 0) {
+    beg = len8 + beg;
+  }
+  if (beg > len8) return mrb_nil_value();
+  if (beg < 0) {
+    beg += len8;
+    if (beg < 0) return mrb_nil_value();
+  }
+  if (beg + len > len8)
+    len = len8 - beg;
+  if (len <= 0) {
+    len = 0;
+  }
+  str2 = str_subseq(mrb, str, beg, len);
+
+  return str2;
+}
+
+static mrb_int
+str_index(mrb_state *mrb, mrb_value str, mrb_value sub, mrb_int offset)
+{
+  mrb_int pos;
+  char *s, *sptr;
+  mrb_int len, slen;
+
+  len = RSTRING_LEN(str);
+  slen = RSTRING_LEN(sub);
+  if (offset < 0) {
+    offset += len;
+    if (offset < 0) return -1;
+  }
+  if (len - offset < slen) return -1;
+  s = RSTRING_PTR(str);
+  if (offset) {
+    s += offset;
+  }
+  if (slen == 0) return offset;
+  /* need proceed one character at a time */
+  sptr = RSTRING_PTR(sub);
+  slen = RSTRING_LEN(sub);
+  len = RSTRING_LEN(str) - offset;
+  pos = mrb_memsearch(sptr, slen, s, len);
+  if (pos < 0) return pos;
+  return pos + offset;
+}
+
+static mrb_value
+mrb_str_aref(mrb_state *mrb, mrb_value str, mrb_value indx)
+{
+  mrb_int idx;
+
+  regexp_check(mrb, indx);
+  switch (mrb_type(indx)) {
+    case MRB_TT_FIXNUM:
+      idx = mrb_fixnum(indx);
+
+num_index:
+      str = str_substr(mrb, str, idx, 1);
+      if (!mrb_nil_p(str) && RSTRING_LEN(str) == 0) return mrb_nil_value();
+      return str;
+
+    case MRB_TT_STRING:
+      if (str_index(mrb, str, indx, 0) != -1)
+        return mrb_str_dup(mrb, indx);
+      return mrb_nil_value();
+
+    case MRB_TT_RANGE:
+      /* check if indx is Range */
+      {
+        mrb_int beg, len;
+        mrb_value tmp;
+
+        len = RSTRING_LEN_UTF8(str);
+        if (mrb_range_beg_len(mrb, indx, &beg, &len, len)) {
+          tmp = str_subseq(mrb, str, beg, len);
+          return tmp;
+        }
+        else {
+          return mrb_nil_value();
+        }
+      }
+    default:
+      idx = mrb_fixnum(indx);
+      goto num_index;
+    }
+    return mrb_nil_value();    /* not reached */
+}
+
+static mrb_value
+mrb_str_aref_m(mrb_state *mrb, mrb_value str)
+{
+  mrb_value a1, a2;
+  int argc;
+
+  argc = mrb_get_args(mrb, "o|o", &a1, &a2);
+  if (argc == 2) {
+    regexp_check(mrb, a1);
+    return str_substr(mrb, str, mrb_fixnum(a1), mrb_fixnum(a2));
+  }
+  if (argc != 1) {
+    mrb_raisef(mrb, E_ARGUMENT_ERROR, "wrong number of arguments (%S for 1)", mrb_fixnum_value(argc));
+  }
+  return mrb_str_aref(mrb, str, a1);
+}
+
+void
+mrb_mruby_string_utf8_gem_init(mrb_state* mrb)
+{
+  struct RClass * s = mrb->string_class;
+
+  mrb_define_method(mrb, s, "[]", mrb_str_aref_m, MRB_ARGS_ANY());
+  mrb_define_method(mrb, s, "slice", mrb_str_aref_m, MRB_ARGS_ANY());
+}
+
+void
+mrb_mruby_string_utf8_gem_final(mrb_state* mrb)
+{
+}

mrbgems/mruby-string-utf8/test/string.rb

+##
+# String(utf8) Test
+
+assert('String#[]') do
+  assert_equal "ち", "こんにちわ世界"[3]
+  assert_equal nil, "こんにちわ世界"[20]
+  assert_equal "世", "こんにちわ世界"[-2]
+  assert_equal "世界", "こんにちわ世界"[-2..-1]
+  assert_equal "んに", "こんにちわ世界"[1,2]
+  assert_equal "世", "こんにちわ世界"["世"]
+  assert_equal "世", "こんにちわ世界"["世"]
+end