int unicode_script()

in src/couch_quickjs/quickjs/libunicode.c [1272:1388]
110 lines of code
25 McCabe index (conditional complexity)

int unicode_script(CharRange *cr,
                   const char *script_name, BOOL is_ext)
{
    int script_idx;
    const uint8_t *p, *p_end;
    uint32_t c, c1, b, n, v, v_len, i, type;
    CharRange cr1_s, *cr1;
    CharRange cr2_s, *cr2 = &cr2_s;
    BOOL is_common;

    script_idx = unicode_find_name(unicode_script_name_table, script_name);
    if (script_idx < 0)
        return -2;
    /* Note: we remove the "Unknown" Script */
    script_idx += UNICODE_SCRIPT_Unknown + 1;

    is_common = (script_idx == UNICODE_SCRIPT_Common ||
                 script_idx == UNICODE_SCRIPT_Inherited);
    if (is_ext) {
        cr1 = &cr1_s;
        cr_init(cr1, cr->mem_opaque, cr->realloc_func);
        cr_init(cr2, cr->mem_opaque, cr->realloc_func);
    } else {
        cr1 = cr;
    }

    p = unicode_script_table;
    p_end = unicode_script_table + countof(unicode_script_table);
    c = 0;
    while (p < p_end) {
        b = *p++;
        type = b >> 7;
        n = b & 0x7f;
        if (n < 96) {
        } else if (n < 112) {
            n = (n - 96) << 8;
            n |= *p++;
            n += 96;
        } else {
            n = (n - 112) << 16;
            n |= *p++ << 8;
            n |= *p++;
            n += 96 + (1 << 12);
        }
        if (type == 0)
            v = 0;
        else
            v = *p++;
        c1 = c + n + 1;
        if (v == script_idx) {
            if (cr_add_interval(cr1, c, c1))
                goto fail;
        }
        c = c1;
    }

    if (is_ext) {
        /* add the script extensions */
        p = unicode_script_ext_table;
        p_end = unicode_script_ext_table + countof(unicode_script_ext_table);
        c = 0;
        while (p < p_end) {
            b = *p++;
            if (b < 128) {
                n = b;
            } else if (b < 128 + 64) {
                n = (b - 128) << 8;
                n |= *p++;
                n += 128;
            } else {
                n = (b - 128 - 64) << 16;
                n |= *p++ << 8;
                n |= *p++;
                n += 128 + (1 << 14);
            }
            c1 = c + n + 1;
            v_len = *p++;
            if (is_common) {
                if (v_len != 0) {
                    if (cr_add_interval(cr2, c, c1))
                        goto fail;
                }
            } else {
                for(i = 0; i < v_len; i++) {
                    if (p[i] == script_idx) {
                        if (cr_add_interval(cr2, c, c1))
                            goto fail;
                        break;
                    }
                }
            }
            p += v_len;
            c = c1;
        }
        if (is_common) {
            /* remove all the characters with script extensions */
            if (cr_invert(cr2))
                goto fail;
            if (cr_op(cr, cr1->points, cr1->len, cr2->points, cr2->len,
                      CR_OP_INTER))
                goto fail;
        } else {
            if (cr_op(cr, cr1->points, cr1->len, cr2->points, cr2->len,
                      CR_OP_UNION))
                goto fail;
        }
        cr_free(cr1);
        cr_free(cr2);
    }
    return 0;
 fail:
    if (is_ext) {
        cr_free(cr1);
        cr_free(cr2);
    }
    goto fail;
}