/* 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++; } }