py: Overhaul and simplify printf/pfenv mechanism.

Previous to this patch the printing mechanism was a bit of a tangled
mess.  This patch attempts to consolidate printing into one interface.

All (non-debug) printing now uses the mp_print* family of functions,
mainly mp_printf.  All these functions take an mp_print_t structure as
their first argument, and this structure defines the printing backend
through the "print_strn" function of said structure.

Printing from the uPy core can reach the platform-defined print code via
two paths: either through mp_sys_stdout_obj (defined pert port) in
conjunction with mp_stream_write; or through the mp_plat_print structure
which uses the MP_PLAT_PRINT_STRN macro to define how string are printed
on the platform.  The former is only used when MICROPY_PY_IO is defined.

With this new scheme printing is generally more efficient (less layers
to go through, less arguments to pass), and, given an mp_print_t*
structure, one can call mp_print_str for efficiency instead of
mp_printf("%s", ...).  Code size is also reduced by around 200 bytes on
Thumb2 archs.

1 files changed, 2 insertions, 2 deletions

diff --git a/py/objint.c b/py/objint.c
index 26e1cc048..64faed636 100644
--- a/py/objint.c
+++ b/py/objint.c
@@ -124,7 +124,7 @@ mp_fp_as_int_class_t mp_classify_fp_as_int(mp_float_t val) {
 #undef MP_FLOAT_EXP_SHIFT_I32
 #endif
 
-void mp_obj_int_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
+void mp_obj_int_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     (void)kind;
     // The size of this buffer is rather arbitrary. If it's not large
     // enough, a dynamic one will be allocated.
@@ -134,7 +134,7 @@ void mp_obj_int_print(void (*print)(void *env, const char *fmt, ...), void *env,
     mp_uint_t fmt_size;
 
     char *str = mp_obj_int_formatted(&buf, &buf_size, &fmt_size, self_in, 10, NULL, '\0', '\0');
-    print(env, "%s", str);
+    mp_print_str(print, str);
 
     if (buf != stack_buf) {
         m_del(char, buf, buf_size);