release/src/router/busybox/libbb/speed_table.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * compact speed_t <-> speed functions for busybox
   4  *
   5  * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
   8  */
   9
  10 #include "libbb.h"
  11
  12 struct speed_map {
  13         unsigned short speed;
  14         unsigned short value;
  15 };
  16
  17 static const struct speed_map speeds[] = {
  18         {B0, 0},
  19         {B50, 50},
  20         {B75, 75},
  21         {B110, 110},
  22         {B134, 134},
  23         {B150, 150},
  24         {B200, 200},
  25         {B300, 300},
  26         {B600, 600},
  27         {B1200, 1200},
  28         {B1800, 1800},
  29         {B2400, 2400},
  30         {B4800, 4800},
  31         {B9600, 9600},
  32 #ifdef  B19200
  33         {B19200, 19200},
  34 #elif defined(EXTA)
  35         {EXTA, 19200},
  36 #endif
  37 #ifdef  B38400
  38         {B38400, 38400/256 + 0x8000U},
  39 #elif defined(EXTB)
  40         {EXTB, 38400/256 + 0x8000U},
  41 #endif
  42 #ifdef B57600
  43         {B57600, 57600/256 + 0x8000U},
  44 #endif
  45 #ifdef B115200
  46         {B115200, 115200/256 + 0x8000U},
  47 #endif
  48 #ifdef B230400
  49         {B230400, 230400/256 + 0x8000U},
  50 #endif
  51 #ifdef B460800
  52         {B460800, 460800/256 + 0x8000U},
  53 #endif
  54 };
  55
  56 enum { NUM_SPEEDS = ARRAY_SIZE(speeds) };
  57
  58 unsigned FAST_FUNC tty_baud_to_value(speed_t speed)
  59 {
  60         int i = 0;
  61
  62         do {
  63                 if (speed == speeds[i].speed) {
  64                         if (speeds[i].value & 0x8000U) {
  65                                 return ((unsigned long) (speeds[i].value) & 0x7fffU) * 256;
  66                         }
  67                         return speeds[i].value;
  68                 }
  69         } while (++i < NUM_SPEEDS);
  70
  71         return 0;
  72 }
  73
  74 speed_t FAST_FUNC tty_value_to_baud(unsigned int value)
  75 {
  76         int i = 0;
  77
  78         do {
  79                 if (value == tty_baud_to_value(speeds[i].speed)) {
  80                         return speeds[i].speed;
  81                 }
  82         } while (++i < NUM_SPEEDS);
  83
  84         return (speed_t) - 1;
  85 }
  86
  87 #if 0
  88 /* testing code */
  89 #include <stdio.h>
  90
  91 int main(void)
  92 {
  93         unsigned long v;
  94         speed_t s;
  95
  96         for (v = 0 ; v < 500000; v++) {
  97                 s = tty_value_to_baud(v);
  98                 if (s == (speed_t) -1) {
  99                         continue;
 100                 }
 101                 printf("v = %lu -- s = %0lo\n", v, (unsigned long) s);
 102         }
 103
 104         printf("-------------------------------\n");
 105
 106         for (s = 0 ; s < 010017+1; s++) {
 107                 v = tty_baud_to_value(s);
 108                 if (!v) {
 109                         continue;
 110                 }
 111                 printf("v = %lu -- s = %0lo\n", v, (unsigned long) s);
 112         }
 113
 114         return 0;
 115 }
 116 #endif