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, 6 insertions, 6 deletions

diff --git a/stmhal/uart.c b/stmhal/uart.c
index 4821da95fd..2da99c2212 100644
--- a/stmhal/uart.c
+++ b/stmhal/uart.c
@@ -330,23 +330,23 @@ void uart_irq_handler(mp_uint_t uart_id) {
 /******************************************************************************/
 /* Micro Python bindings                                                      */
 
-STATIC void pyb_uart_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
+STATIC void pyb_uart_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     pyb_uart_obj_t *self = self_in;
     if (!self->is_enabled) {
-        print(env, "UART(%u)", self->uart_id);
+        mp_printf(print, "UART(%u)", self->uart_id);
     } else {
         mp_int_t bits = (self->uart.Init.WordLength == UART_WORDLENGTH_8B ? 8 : 9);
         if (self->uart.Init.Parity != UART_PARITY_NONE) {
             bits -= 1;
         }
-        print(env, "UART(%u, baudrate=%u, bits=%u, parity=",
+        mp_printf(print, "UART(%u, baudrate=%u, bits=%u, parity=",
             self->uart_id, self->uart.Init.BaudRate, bits);
         if (self->uart.Init.Parity == UART_PARITY_NONE) {
-            print(env, "None");
+            mp_print_str(print, "None");
         } else {
-            print(env, "%u", self->uart.Init.Parity == UART_PARITY_EVEN ? 0 : 1);
+            mp_printf(print, "%u", self->uart.Init.Parity == UART_PARITY_EVEN ? 0 : 1);
         }
-        print(env, ", stop=%u, timeout=%u, timeout_char=%u, read_buf_len=%u)",
+        mp_printf(print, ", stop=%u, timeout=%u, timeout_char=%u, read_buf_len=%u)",
             self->uart.Init.StopBits == UART_STOPBITS_1 ? 1 : 2,
             self->timeout, self->timeout_char, self->read_buf_len);
     }