rom/kernel/_displayalert.c

   1 /*
   2     Copyright © 1995-2013, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc:
   6 */
   7
   8 #include <kernel_base.h>
   9 #include <kernel_debug.h>
  10
  11 #define ALERT_WIDTH 80
  12
  13 static inline void PrintChars(char c, ULONG n, struct KernelBase *KernelBase)
  14 {
  15     while (n--)
  16         krnPutC(c, KernelBase);
  17 }
  18
  19 /*
  20  * This function calculates length of line.
  21  * It's similar to strlen(), but stops also at LF and FF codes.
  22  */
  23 static inline int linelen(const char *str)
  24 {
  25     int l;
  26
  27     for (l = 0; str[l] && str[l] != '\n' && str[l] != 0x0F; l++);
  28     return l;
  29 }
  30
  31 static const char *PrintCentered(const char *str, struct KernelBase *KernelBase)
  32 {
  33     int len = linelen(str);
  34     int i;
  35     ULONG s;
  36
  37     if (len > (ALERT_WIDTH - 2))
  38             len = (ALERT_WIDTH - 2);
  39
  40     s = ALERT_WIDTH - 2 - len;
  41
  42     krnPutC('#', KernelBase);
  43     if (s & 1)
  44         krnPutC(' ', KernelBase);
  45     s >>= 1;
  46     PrintChars(' ', s, KernelBase);
  47
  48     for (i = 0; i < len; i++)
  49         krnPutC(*str++, KernelBase);
  50
  51     PrintChars(' ', s, KernelBase);
  52     krnPutC('#', KernelBase);
  53     krnPutC('\n', KernelBase);
  54
  55     return str;
  56 }
  57
  58 static inline void PrintFrame(struct KernelBase *KernelBase)
  59 {
  60     PrintChars('#', ALERT_WIDTH, KernelBase);
  61     krnPutC('\n', KernelBase);
  62 }
  63
  64 /*
  65  * This entry point just displays the message. It doesn't make any decisions
  66  * what to do next.
  67  * Because of this it misses 'code' argument.
  68  * The kernel can use it internally, for displaying messages about
  69  * critical startup failures.
  70  */
  71 void krnDisplayAlert(const char *text, struct KernelBase *KernelBase)
  72 {
  73     unsigned int i;
  74
  75     /* Make sure that the output starts from a new line */
  76     krnPutC('\n', KernelBase);
  77
  78     PrintFrame(KernelBase);
  79
  80     /* Print first three lines (title, task and error) centered */
  81     for (i = 0; i < 3; i++)
  82     {
  83         text = PrintCentered(text, KernelBase);
  84
  85         if (*text == 0) /* Handle early NULL terminator */
  86             break;
  87
  88         text++; /* Skip a newline */
  89     }
  90
  91     PrintFrame(KernelBase);
  92
  93     /* Print the rest of alert text (if any) */
  94     if (*text)
  95     {
  96         while (*text)
  97             krnPutC(*text++, KernelBase);
  98
  99         krnPutC('\n', KernelBase);
 100         PrintFrame(KernelBase);
 101     }
 102 }