gcc/libgo/runtime/go-print.c

171 lines
2.8 KiB
C

/* go-print.c -- support for the go print statement.
Copyright 2009 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file. */
#include <math.h>
#include <stdint.h>
#include <stdio.h>
#include "array.h"
#include "go-panic.h"
#include "go-string.h"
#include "interface.h"
/* This implements the various little functions which are called by
the predeclared functions print/println/panic/panicln. */
void
__go_print_space ()
{
putc (' ', stderr);
}
void
__go_print_nl ()
{
putc ('\n', stderr);
}
void
__go_print_string (struct __go_string val)
{
fprintf (stderr, "%.*s", (int) val.__length, (const char *) val.__data);
}
void
__go_print_uint64 (uint64_t val)
{
fprintf (stderr, "%llu", (unsigned long long) val);
}
void
__go_print_int64 (int64_t val)
{
fprintf (stderr, "%lld", (long long) val);
}
void
__go_print_double (double v)
{
char buf[20];
int e, s, i, n;
double h;
if (isnan (v))
{
fputs ("NaN", stderr);
return;
}
if (__builtin_isinf (v))
{
putc (v < 0 ? '-' : '+', stderr);
fputs ("Inf", stderr);
return;
}
/* The number of digits printed. */
n = 7;
/* The exponent. */
e = 0;
/* The sign. */
s = 0;
if (v != 0)
{
if (v < 0)
{
v = -v;
s = 1;
}
/* Normalize. */
while (v >= 10)
{
++e;
v /= 10;
}
while (v < 1)
{
--e;
v *= 10;
}
/* Round. */
h = 5;
for (i = 0; i < n; ++i)
h /= 10;
v += h;
if (v >= 10)
{
++e;
v /= 10;
}
}
/* The format is +d.dddd+edd. */
buf[0] = s ? '-' : '+';
for (i = 0; i < n; ++i)
{
int d;
d = v;
buf[i + 2] = d + '0';
v -= d;
v *= 10;
}
buf[1] = buf[2];
buf[2] = '.';
buf[n + 2] = 'e';
buf[n + 3] = e < 0 ? '-' : '+';
if (e < 0)
e = - e;
buf[n + 4] = e / 100 + '0';
buf[n + 5] = (e / 10) % 10 + '0';
buf[n + 6] = e % 10 + '0';
buf[n + 7] = '\0';
fputs (buf, stderr);
}
void
__go_print_complex (__complex double val)
{
putc ('(', stderr);
__go_print_double (__builtin_creal (val));
__go_print_double (__builtin_cimag (val));
fputs ("i)", stderr);
}
void
__go_print_bool (_Bool val)
{
fputs (val ? "true" : "false", stderr);
}
void
__go_print_pointer (void *val)
{
fprintf (stderr, "0x%lx", (unsigned long) (uintptr_t) val);
}
void
__go_print_empty_interface (struct __go_empty_interface e)
{
fprintf (stderr, "(%p,%p)", e.__type_descriptor, e.__object);
}
void
__go_print_interface (struct __go_interface i)
{
fprintf (stderr, "(%p,%p)", i.__methods, i.__object);
}
void
__go_print_slice (struct __go_open_array val)
{
fprintf (stderr, "[%d/%d]", val.__count, val.__capacity);
__go_print_pointer (val.__values);
}