ChibiOS C shell variables

usbcdc.c

/**
 * File:    usbcdc.h
 */
typedef struct
{
	const char* name;
	float* loc;
} usbcdcParameterStruct_t;
void usbcdcSetShellVars(const usbcdcParameterStruct_t** vars);

/**
 * File:    usbcdc.c
 */
static const usbcdcParameterStruct_t** mShellVars;
void usbcdcSetShellVars(const usbcdcParameterStruct_t** vars)
{
  mShellVars = vars;
}
static void cmd_get(BaseSequentialStream *chp, int argc, char *argv[])
{
  (void)argc;
  (void)argv;
  uint8_t ctr;
  for(ctr = 0; mShellVars[ctr] != NULL; ctr++)
  {
    chprintf(chp, "%s = %.3f\r\n", mShellVars[ctr]->name, *mShellVars[ctr]->loc);
  }
}
static void cmd_set(BaseSequentialStream *chp, int argc, char *argv[])
{
  uint8_t ctr;
  if(argc != 2) 
  {
    chprintf(chp, "Too few arguments\r\n");
    return;
  }
  for(ctr = 0; mShellVars[ctr] != NULL; ctr++)
  {
    if(strcmp(mShellVars[ctr]->name, argv[0]) == 0)
    {
      (*mShellVars[ctr]->loc) = stof(argv[1]);
      chprintf(chp, "%s = %.3f\r\n", mShellVars[ctr]->name, *mShellVars[ctr]->loc);
      return;
    }
  }
  chprintf(chp, "%s not found\r\n", argv[0]);
}
static const ShellCommand commands[] = {
    {"mem", cmd_mem},
    {"threads", cmd_threads},
    {"get", cmd_get},
    {"set", cmd_set},
    {NULL, NULL}
};
static float stof(const char* s)
{
  float rez = 0, fact = 1;
  if (*s == '-')
  {
    s++;
    fact = -1;
  }
  for (int point_seen = 0; *s; s++)
  {
    if (*s == '.')
    {
      point_seen = 1; 
      continue;
    }
    int d = *s - '0';
    if (d >= 0 && d <= 9)
    {
      if (point_seen) fact /= 10.0f;
      rez = rez * 10.0f + (float)d;
    }
  }
  return rez * fact;
};

/**
 * File: main.c
 */
static float mFoo, mBar;
static const usbcdcParameterStruct_t mShellParmFoo = {"foo", &mFoo};
static const usbcdcParameterStruct_t mShellParmBar = {"bar", &mBar};

static const usbcdcParameterStruct_t* mShellVars[] = 
{
  &mShellParmFoo,
  &mShellParmBar,
  NULL
};

int main(void) 
{
  usbcdcSetShellVars(mShellVars);
  while(1);
  return 0;
}