45 lines
1.5 KiB
C
45 lines
1.5 KiB
C
/* 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 way system messages end up in the kernel messages buffer and can be
|
|
* reviewed at a later time.
|
|
*
|
|
* This routine can only be used by servers and device drivers. The kernel
|
|
* must define its own kputc(). Note that the IS also defines its own kputc()
|
|
* to directly call the TTY instead of the kernel, because it does not want
|
|
* to pollute the kernel message buffer with its debug dumps.
|
|
*/
|
|
|
|
#include "utils.h"
|
|
|
|
/*===========================================================================*
|
|
* kputc *
|
|
*===========================================================================*/
|
|
void kputc(c)
|
|
int c;
|
|
{
|
|
/* Accumulate another character. If 0 or buffer full, print it. */
|
|
|
|
static int buf_count; /* # characters in the buffer */
|
|
static char print_buf[80]; /* output is buffered here */
|
|
message m;
|
|
|
|
if ((c == 0 && buf_count > 0) || buf_count == sizeof(print_buf)) {
|
|
/* Send the buffer to the system task, or, if this process is not a
|
|
* server yet, to standard error.
|
|
*/
|
|
m.DIAG_BUF_COUNT = buf_count;
|
|
m.DIAG_PRINT_BUF = print_buf;
|
|
m.DIAG_PROC_NR = SELF;
|
|
m.m_type = DIAGNOSTICS;
|
|
if (_sendrec(PRINTF_PROC, &m) != 0) {
|
|
m.m1_i1 = 2;
|
|
m.m1_i2 = buf_count;
|
|
m.m1_p1 = print_buf;
|
|
m.m_type = WRITE;
|
|
(void) _sendrec(FS, &m);
|
|
}
|
|
buf_count = 0;
|
|
}
|
|
if (c != 0) print_buf[buf_count++] = c;
|
|
}
|