/*

UVR-Linux - a collection of programs to access data on

Technische Alternative UVR-type devices.

Copyright (C) 2012 Markus Brueckner

This program is free software: you can redistribute it and/or modify

it under the terms of the GNU General Public License as published by

the Free Software Foundation, either version 3 of the License, or

(at your option) any later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program. If not, see <http://www.gnu.org/licenses/>.

*/

#include <stdio.h>

#include <errno.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <sys/wait.h>

#include "communication.h"

#include "logging.h"

void daemonize()

{

pid_t pid = fork();

if (pid > 0) {

// we're in the parent process -> exit

exit(0);

}

// standard UNIX daemon setup

umask(0);

pid_t sid = setsid();

if (sid < 0) {

fprintf(stderr, "Could not get new session id");

exit(-1);

}

if ((chdir("/")) < 0) {

fprintf(stderr, "Could not change directory to /");

exit(-1);

}

log_output(LOG_DEBUG, "Sucessfully daemonized reader.\n");

// close STDIO

close(STDIN_FILENO);

close(STDOUT_FILENO);

close(STDERR_FILENO);

}

/**

* print a sensor value to stdout

*/

void printValue(char *prefix, struct Value *value)

{

printf("%s%d: ", prefix, value->valueID);

switch (value->valueType) {

case UNUSED:

printf("---");

break;

case DIGITAL:

printf(value->value.enabled ? "on" : "off");

break;

case TEMPERATURE:

printf("%.1f °C", value->value.temperature);

break;

case FLOW:

printf("%d l/h", value->value.flow);

break;

case HEAT:

printf("%.2f kW (total: %.1f kWh)", value->value.heat.current, value->value.heat.total);

break;

default:

printf("UNKNOWN");

break;

}

}

void printValueList(char *prefix, struct ValueListNode *head)

{

struct ValueListNode *tmp;

tmp = head;

while (tmp != NULL) {

printValue(prefix, &(tmp->value));

putchar('\n');

tmp = tmp->next;

}

}

void setEnvValue(char *prefix, struct Value *value)

{

char varbuf[100];

char valuebuf[100];

snprintf(varbuf, 100, "%s_%d_TYPE", prefix, (int)(value->valueID));

switch(value->valueType) {

case UNUSED:

snprintf(valuebuf, 100, "UNUSED");

break;

case DIGITAL:

snprintf(valuebuf, 100, "DIGITAL");

break;

case TEMPERATURE:

snprintf(valuebuf, 100, "TEMPERATURE");

break;

case FLOW:

snprintf(valuebuf, 100, "FLOW");

break;

case HEAT:

snprintf(valuebuf, 100, "HEAT");

break;

}

setenv(varbuf, valuebuf, 1);

snprintf(varbuf, 100, "%s_%d_VALUE", prefix, (int)(value->valueID));

switch(value->valueType) {

case UNUSED:

snprintf(valuebuf, 100, "UNUSED");

break;

case DIGITAL:

snprintf(valuebuf, 100, value->value.enabled ? "1" : "0");

break;

case TEMPERATURE:

snprintf(valuebuf, 100, "%.1f", value->value.temperature);

break;

case FLOW:

snprintf(valuebuf, 100, "%d", value->value.flow);

break;

case HEAT:

snprintf(varbuf, 100, "%s_%d_VALUE_CURRENT", prefix, (int)(value->valueID));

snprintf(valuebuf, 100, "%.2f", value->value.heat.current);

setenv(varbuf, valuebuf, 1);

snprintf(varbuf, 100, "%s_%d_VALUE_TOTAL", prefix, (int)(value->valueID));

snprintf(valuebuf, 100, "%.1f", value->value.heat.total);

}

setenv(varbuf, valuebuf, 1);

}

void setEnvList(char *prefix, struct ValueListNode *head)

{

struct ValueListNode *it;

char valuebuf[100];

char varbuf[100];

it = head;

int counter = 0;

while (it != NULL) {

setEnvValue(prefix, &(it->value));

++counter;

it = it->next;

}

snprintf(valuebuf, 100, "%d", counter);

snprintf(varbuf, 100, "%sS", prefix);

setenv(varbuf, valuebuf, 1);

}

void executeProgram(char *program, struct SystemState *state)

{

pid_t child;

if (state != NULL) {

child = fork();

if (child == 0) {

setEnvList("UVR_INPUT", state->inputs);

setEnvList("UVR_OUTPUT", state->outputs);

setEnvList("UVR_HEATREG", state->heatRegisters);

log_output(LOG_DEBUG, "Executing %s\n", program);

system(program);

log_output(LOG_DEBUG, "%s finished\n", program);

exit(0);

}

else {

waitpid(child, NULL, 0); // sleep until the child returns

log_output(LOG_DEBUG, "Child returned\n");

}

}

}

void printUsage(char *command)

{

fprintf(stderr, "Usage: %s [-s <program>] [-d <delay>] [-c <count>] <USB device>\n", command);

fprintf(stderr, " -s Execute the program given as a parameter and\n");

fprintf(stderr, " hand it the values in the environment instead\n");

fprintf(stderr, " of printing them to stdout. The values are handed\n");

fprintf(stderr, " over in form of environment variables named\n");

fprintf(stderr, " UVR_INPUT_<number>_<type>, with <number> being\n");

fprintf(stderr, " the sensor number and <type> being either\n");

fprintf(stderr, " VALUE or TYPE. The _TYPE-variable contains one\n");

fprintf(stderr, " of UNUSED, DIGITAL, TEMPERATURE or FLOW, corresponding\n");

fprintf(stderr, " to the respective sensor types. Digital sensors may have a value\n");

fprintf(stderr, " of 0 or 1, temperature sensors contain the temperature in °C,\n");

fprintf(stderr, " flow sensor values are in l/h. The number of inputs is contained\n");

fprintf(stderr, " in UVR_INPUTS.\n");

fprintf(stderr, " -d Set the delay between the value updates in seconds. (default: 10)\n");

fprintf(stderr, " -c Set the repetition counter. A repetition counter of 0 means run infinitely. (default: 0)\n");

fprintf(stderr, " -D Run the program as a daemon. The reader forks into the background and detaches from the terminal\n");

fprintf(stderr, " This implies -s as a daemon cannot make any output.\n");

fprintf(stderr, " -v Enable debug output.\n");

}

int main(int argc, char *argv[]) {

struct USBConnection *connection;

int opt;

int repeatCount = 0;

char *script = NULL;

int delay = 10;

int daemon = 0;

while ((opt = getopt(argc, argv, "s:d:c:Dv")) != -1) {

switch (opt) {

case 's':

script = optarg;

break;

case 'd':

delay = atoi(optarg);

break;

case 'c':

repeatCount = atoi(optarg);

break;

case 'D':

daemon = 1;

break;

case 'v':

enable_debug();

break;

default:

printUsage(argv[0]);

return -1;

}

}

if (optind >= argc) {

fprintf(stderr, "Missing USB device parameter.\n");

printUsage(argv[0]);

return -1;

}

if (daemon && script == NULL) {

fprintf(stderr, "Missing script parameter. Running the program as a daemon implies -s.\n");

return -1;

}

if (daemon) {

initlog(1);

daemonize();

}

else {

initlog(0);

}

log_output(LOG_DEBUG, "Opening USB device\n");

connection = initUSBConnection(argv[optind]);

if (connection != NULL) {

int i;

int increment = 1;

log_output(LOG_INFO, "Connection initialization successful. UVR mode 0x%X\n", (unsigned int)connection->uvr_mode);

if (repeatCount == 0) {

increment = 0;

repeatCount = 1; // prepare the values in a way that the loop below runs infinitely

}

for (i = 0; i < repeatCount; i+=increment) {

struct SystemState *result;

result = readCurrentData(connection);

if (result != NULL) {

if (script != NULL) {

executeProgram(script, result);

}

else {

printf("Inputs\n");

printValueList("S", result->inputs);

printf("Outputs\n");

printValueList("O", result->outputs);

printf("Heat registers\n");

printValueList("", result->heatRegisters);

}

freeSystemState(result);

result = NULL;

}

sleep(delay);

}

}

else {

fprintf(stderr, "Could not initialize connection to UVR. %s\n", strerror(errno));

cleanupUSBConnection(connection);

return -1;

}

cleanupUSBConnection(connection);

return 0;

}