Add `mrb_float_to_cstr()` MRB_API function
In order to share the same operation with `mrb_float_to_str()`,
the internal structure is modified.
MODIFY
include/mruby/numeric.h
include/mruby/numeric.h
@@ -37,6 +37,7 @@ MRB_API mrb_value mrb_fixnum_to_str(mrb_state *mrb, mrb_value x, mrb_int base);
/* ArgumentError if format string doesn't match /%(\.[0-9]+)?[aAeEfFgG]/ */
#ifndef MRB_WITHOUT_FLOAT
MRB_API mrb_value mrb_float_to_str(mrb_state *mrb, mrb_value x, const char *fmt);
+MRB_API int mrb_float_to_cstr(mrb_state *mrb, char *buf, size_t len, const char *fmt, mrb_float f);
MRB_API mrb_float mrb_to_flo(mrb_state *mrb, mrb_value x);
MRB_API mrb_value mrb_int_value(mrb_state *mrb, mrb_float f);
#endif

MODIFY
src/fmt_fp.c
src/fmt_fp.c
@@ -37,9 +37,19 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#include <mruby.h>
#include <mruby/string.h>
+struct fmt_args;
+
+typedef void output_func(struct fmt_args *f, const char *s, size_t l);
+
struct fmt_args {
mrb_state *mrb;
- mrb_value str;
+ output_func *output;
+ void *opaque;
+};
+
+struct mrb_cstr {
+ char *buf;
+ size_t len;
};
#define MAX(a,b) ((a)>(b) ? (a) : (b))
@@ -56,10 +66,37 @@ struct fmt_args {
#define FLAGMASK (ALT_FORM|ZERO_PAD|LEFT_ADJ|PAD_POS|MARK_POS)
+static output_func strcat_value;
+static output_func strcat_cstr;
+
+static void
+strcat_value(struct fmt_args *f, const char *s, size_t l)
+{
+ mrb_value str = *(mrb_value*)f->opaque;
+ mrb_str_cat(f->mrb, str, s, l);
+}
+
+static void
+strcat_cstr(struct fmt_args *f, const char *s, size_t l)
+{
+ struct mrb_cstr *cstr = (struct mrb_cstr*)f->opaque;
+
+ if (l > cstr->len) {
+ mrb_state *mrb = f->mrb;
+
+ mrb_raise(mrb, E_ARGUMENT_ERROR, "string buffer too small");
+ }
+
+ memcpy(cstr->buf, s, l);
+
+ cstr->buf += l;
+ cstr->len -= l;
+}
+
static void
out(struct fmt_args *f, const char *s, size_t l)
{
- mrb_str_cat(f->mrb, f->str, s, l);
+ f->output(f, s, l);
}
#define PAD_SIZE 256
@@ -377,13 +414,33 @@ MRB_API mrb_value
mrb_float_to_str(mrb_state *mrb, mrb_value flo, const char *fmt)
{
struct fmt_args f;
+ mrb_value str = mrb_str_new_capa(mrb, 24);
f.mrb = mrb;
- f.str = mrb_str_new_capa(mrb, 24);
+ f.output = strcat_value;
+ f.opaque = (void*)&str;
if (fmt_core(&f, fmt, mrb_float(flo)) < 0) {
mrb_raise(mrb, E_ARGUMENT_ERROR, "invalid format string");
}
- return f.str;
+ return str;
+}
+
+MRB_API int
+mrb_float_to_cstr(mrb_state *mrb, char *buf, size_t len, const char *fmt, mrb_float fval)
+{
+ struct fmt_args f;
+ struct mrb_cstr cstr;
+
+ cstr.buf = buf;
+ cstr.len = len - 1; /* reserve NUL terminator */
+ f.mrb = mrb;
+ f.output = strcat_cstr;
+ f.opaque = (void*)&cstr;
+ if (fmt_core(&f, fmt, fval) < 0) {
+ mrb_raise(mrb, E_ARGUMENT_ERROR, "invalid format string");
+ }
+ *cstr.buf = '\0';
+ return cstr.buf - buf;
}
#else /* MRB_DISABLE_STDIO || _WIN32 || _WIN64 */
#include <mruby.h>
@@ -397,5 +454,11 @@ mrb_float_to_str(mrb_state *mrb, mrb_value flo, const char *fmt)
snprintf(buf, sizeof(buf), fmt, mrb_float(flo));
return mrb_str_new_cstr(mrb, buf);
}
+
+MRB_API int
+mrb_float_to_cstr(mrb_state *mrb, char *buf, size_t len, const char *fmt, mrb_float fval)
+{
+ return snprintf(buf, len, fmt, fval);
+}
#endif /* MRB_DISABLE_STDIO || _WIN32 || _WIN64 */
#endif

Add `mrb_float_to_cstr()` MRB_API function

In order to share the same operation with `mrb_float_to_str()`,
the internal structure is modified.