diff options
Diffstat (limited to 'mrbgems/mruby-string-ext/src/string.c')
| -rw-r--r-- | mrbgems/mruby-string-ext/src/string.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/mrbgems/mruby-string-ext/src/string.c b/mrbgems/mruby-string-ext/src/string.c index 7e87b3db4..45d406f6f 100644 --- a/mrbgems/mruby-string-ext/src/string.c +++ b/mrbgems/mruby-string-ext/src/string.c @@ -5,6 +5,9 @@ #include <mruby/string.h> #include <mruby/range.h> +#define MAX(a,b) ((a)>(b) ? (a) : (b)) +#define MIN(a,b) ((a)<(b) ? (a) : (b)) + static mrb_value mrb_str_getbyte(mrb_state *mrb, mrb_value str) { @@ -509,6 +512,93 @@ mrb_str_ord(mrb_state* mrb, mrb_value str) } #endif +static mrb_value +mrb_str_just(mrb_state* mrb, mrb_value str, mrb_bool right_just) +{ + mrb_value new_str; + mrb_int idx = 0, i = 0, bytes_to_copy = 0, start_pos = 0, final_pos = 0, + pad_str_length = 0; + mrb_int str_length = RSTRING_LEN(str); + const char *pad_str = NULL; + char *new_str_ptr = NULL; + + mrb_get_args(mrb, "i|s!", &idx, &pad_str, &pad_str_length); + + if (pad_str == NULL) + { + pad_str = " "; + pad_str_length = 1; + } + + if (pad_str_length == 0) + { + mrb_raise(mrb, E_ARGUMENT_ERROR, "zero width padding"); + } + + if (idx <= str_length) + { + return str; + } + + new_str = mrb_str_dup(mrb, str); + mrb_str_resize(mrb, new_str, idx); + + new_str_ptr = RSTRING_PTR(new_str); + + if (right_just) + { + memcpy(new_str_ptr + idx - str_length, RSTRING_PTR(str), str_length); + } + + start_pos = right_just ? 0 : str_length; + final_pos = idx - (right_just ? str_length : 0); + + for (i = start_pos; i < final_pos; i += pad_str_length) + { + bytes_to_copy = idx - i - (right_just ? str_length : 0); + bytes_to_copy = MIN(pad_str_length, bytes_to_copy); + memcpy(new_str_ptr + i, pad_str, bytes_to_copy); + } + + return new_str; +} + +/* + * call-seq: + * str.ljust(integer, padstr=' ') -> new_str + * + * If <i>integer</i> is greater than the length of <i>str</i>, returns a new + * <code>String</code> of length <i>integer</i> with <i>str</i> left justified + * and padded with <i>padstr</i>; otherwise, returns <i>str</i>. + * + * "hello".ljust(4) #=> "hello" + * "hello".ljust(20) #=> "hello " + * "hello".ljust(20, '1234') #=> "hello123412341234123" + */ +static mrb_value +mrb_str_ljust(mrb_state* mrb, mrb_value str) +{ + return mrb_str_just(mrb, str, FALSE); +} + +/* + * call-seq: + * str.rjust(integer, padstr=' ') -> new_str + * + * If <i>integer</i> is greater than the length of <i>str</i>, returns a new + * <code>String</code> of length <i>integer</i> with <i>str</i> right justified + * and padded with <i>padstr</i>; otherwise, returns <i>str</i>. + * + * "hello".rjust(4) #=> "hello" + * "hello".rjust(20) #=> " hello" + * "hello".rjust(20, '1234') #=> "123412341234123hello" + */ +static mrb_value +mrb_str_rjust(mrb_state* mrb, mrb_value str) +{ + return mrb_str_just(mrb, str, TRUE); +} + void mrb_mruby_string_ext_gem_init(mrb_state* mrb) { @@ -530,6 +620,8 @@ mrb_mruby_string_ext_gem_init(mrb_state* mrb) mrb_define_method(mrb, s, "lines", mrb_str_lines, MRB_ARGS_NONE()); mrb_define_method(mrb, s, "succ", mrb_str_succ, MRB_ARGS_NONE()); mrb_define_method(mrb, s, "succ!", mrb_str_succ_bang, MRB_ARGS_NONE()); + mrb_define_method(mrb, s, "ljust", mrb_str_ljust, MRB_ARGS_REQ(1)|MRB_ARGS_OPT(1)); + mrb_define_method(mrb, s, "rjust", mrb_str_rjust, MRB_ARGS_REQ(1)|MRB_ARGS_OPT(1)); mrb_alias_method(mrb, s, mrb_intern_lit(mrb, "next"), mrb_intern_lit(mrb, "succ")); mrb_alias_method(mrb, s, mrb_intern_lit(mrb, "next!"), mrb_intern_lit(mrb, "succ!")); mrb_define_method(mrb, s, "ord", mrb_str_ord, MRB_ARGS_NONE()); |