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/* A server must occasionally print some message. It uses a simple version of
* printf() found in the system lib that calls kputc() to output characters.
* Printing is done with a call to the kernel, and not by going through FS.
*
* This routine can only be used by servers and device drivers. The kernel
* must define its own kputc(). Note that the log driver also defines its own
* kputc() to directly call the TTY instead of going through this library.
*/
#include "sysutil.h"
static char print_buf[DIAG_BUFSIZE]; /* output is buffered here */
/*===========================================================================*
* kputc *
*===========================================================================*/
void kputc(int c)
{
/* Accumulate another character. If 0 or buffer full, print it. */
static int buf_count; /* # characters in the buffer */
if ((c == 0 && buf_count > 0) || buf_count == sizeof(print_buf)) {
sys_diagctl_diag(print_buf, buf_count);
buf_count = 0;
}
if (c != 0) {
/* Append a single character to the output buffer. */
print_buf[buf_count] = c;
buf_count++;
}
}
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