josh/hos
1
0
Fork 0
Code Issues 1 Pull Requests Projects Releases Wiki Activity

hos_printf: handle field width, zero-padding, and left-justifiying conversion specifiers

Browse Source
This commit is contained in:
Josh Holtrop 2020-10-20 19:56:30 -04:00
parent 9bddf11ee4
commit 784009ba6c
1 changed files with 52 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

58
src/hos_printf.c
View File

@ -60,11 +60,38 @@ static size_t format_hex(char * buffer, int v, bool upper)
return sz;
}
static void pad_write(const stream_t * stream, const char * data, size_t length, bool leading_zero, bool left_just, size_t width)
{
if (left_just)
{
stream->write(data, length);
while (length < width)
{
stream->write1(' ');
length++;
}
}
else
{
char fill = leading_zero ? '0' : ' ';
size_t l = length;
while (l < width)
{
stream->write1(fill);
l++;
}
stream->write(data, length);
}
}
void hos_vprintf(const stream_t * stream, const char * fmt, va_list va)
{
bool in_conv = false;
char c;
char buffer[12];
size_t width;
bool leading_zero;
bool left_just;
while ((c = *fmt))
{
if (in_conv)
@ -78,40 +105,40 @@ void hos_vprintf(const stream_t * stream, const char * fmt, va_list va)
{
unsigned int v = va_arg(va, unsigned int);
size_t length = format_hex(buffer, v, true);
stream->write(buffer, length);
pad_write(stream, buffer, length, leading_zero, left_just, width);
}
break;
case 'c':
{
char ch = va_arg(va, int);
stream->write1(ch);
pad_write(stream, &ch, 1u, leading_zero, left_just, width);
}
break;
case 'd':
{
int v = va_arg(va, int);
size_t length = format_dec(buffer, v);
stream->write(buffer, length);
pad_write(stream, buffer, length, leading_zero, left_just, width);
}
break;
case 's':
{
const char * s = va_arg(va, const char *);
stream->write(s, strlen(s));
pad_write(stream, s, strlen(s), leading_zero, left_just, width);
}
break;
case 'u':
{
unsigned int v = va_arg(va, unsigned int);
size_t length = format_udec(buffer, v);
stream->write(buffer, length);
pad_write(stream, buffer, length, leading_zero, left_just, width);
}
break;
case 'x':
{
unsigned int v = va_arg(va, unsigned int);
size_t length = format_hex(buffer, v, false);
stream->write(buffer, length);
pad_write(stream, buffer, length, leading_zero, left_just, width);
}
break;
}
@ -120,6 +147,25 @@ void hos_vprintf(const stream_t * stream, const char * fmt, va_list va)
else if (c == '%')
{
in_conv = true;
width = 0u;
leading_zero = false;
left_just = false;
if (fmt[1] == '-')
{
left_just = true;
fmt++;
}
if (fmt[1] == '0')
{
leading_zero = true;
fmt++;
}
while (('0' <= fmt[1]) && (fmt[1] <= '9'))
{
width *= 10u;
width += (fmt[1] - '0');
fmt++;
}
}
else
{