sim_console_c.c

   1 #include <stdint.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <stdbool.h>
   5 #include <string.h>
   6 #include <termios.h>
   7 #include <unistd.h>
   8 #include <poll.h>
   9
  10
  11 #define vhpi0   2       /* forcing 0 */
  12 #define vhpi1   3       /* forcing 1 */
  13
  14 static uint64_t from_std_logic_vector(unsigned char *p, unsigned long len)
  15 {
  16         unsigned long ret = 0;
  17
  18         if (len > 64) {
  19                 fprintf(stderr, "%s: invalid length %lu\n", __func__, len);
  20                 exit(1);
  21         }
  22
  23         for (unsigned long i = 0; i < len; i++) {
  24                 unsigned char bit;
  25
  26                 if (*p == vhpi0) {
  27                         bit = 0;
  28                 } else if (*p == vhpi1) {
  29                         bit = 1;
  30                 } else {
  31                         fprintf(stderr, "%s: bad bit %d\n", __func__, *p);
  32                         bit = 0;
  33                 }
  34
  35                 ret = (ret << 1) | bit;
  36                 p++;
  37         }
  38
  39         return ret;
  40 }
  41
  42 static void to_std_logic_vector(unsigned long val, unsigned char *p,
  43                                 unsigned long len)
  44 {
  45         if (len > 64) {
  46                 fprintf(stderr, "%s: invalid length %lu\n", __func__, len);
  47                 exit(1);
  48         }
  49
  50         for (unsigned long i = 0; i < len; i++) {
  51                 if ((val >> (len-1-i) & 1))
  52                         *p = vhpi1;
  53                 else
  54                         *p = vhpi0;
  55
  56                 p++;
  57         }
  58 }
  59
  60 static struct termios oldt;
  61
  62 static void restore_termios(void)
  63 {
  64         tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
  65 }
  66
  67 static void nonblocking(void)
  68 {
  69         static bool initialized = false;
  70
  71         if (!initialized) {
  72                 static struct termios newt;
  73
  74                 tcgetattr(STDIN_FILENO, &oldt);
  75                 newt = oldt;
  76                 newt.c_lflag &= ~(ICANON|ECHO);
  77
  78                 newt.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
  79                 newt.c_oflag &= ~(OPOST);
  80                 newt.c_cflag |= (CS8);
  81                 newt.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
  82
  83                 tcsetattr(STDIN_FILENO, TCSANOW, &newt);
  84                 initialized = true;
  85                 atexit(restore_termios);
  86         }
  87 }
  88
  89 void sim_console_read(unsigned char *__rt)
  90 {
  91         int ret;
  92         unsigned long val = 0;
  93
  94         nonblocking();
  95
  96         ret = read(STDIN_FILENO, &val, 1);
  97         if (ret != 1) {
  98                 fprintf(stderr, "%s: read of stdin returns %d\n", __func__, ret);
  99                 exit(1);
 100         }
 101
 102         //fprintf(stderr, "read returns %c\n", val);
 103
 104         to_std_logic_vector(val, __rt, 64);
 105 }
 106
 107 void sim_console_poll(unsigned char *__rt)
 108 {
 109         int ret;
 110         struct pollfd fdset[1];
 111         uint8_t val = 0;
 112
 113         nonblocking();
 114
 115         memset(fdset, 0, sizeof(fdset));
 116
 117         fdset[0].fd = STDIN_FILENO;
 118         fdset[0].events = POLLIN;
 119
 120         ret = poll(fdset, 1, 0);
 121         //fprintf(stderr, "poll returns %d\n", ret);
 122
 123         if (ret == 1)
 124                 val = 1;
 125
 126         to_std_logic_vector(val, __rt, 64);
 127 }
 128
 129 void sim_console_write(unsigned char *__rs)
 130 {
 131         uint8_t val;
 132
 133         val = from_std_logic_vector(__rs, 64);
 134
 135         fprintf(stderr, "%c", val);
 136 }