dwmblocks-ekollof/dwmblocks.c

#include <X11/Xlib.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#define LENGTH(X) (sizeof(X) / sizeof(X[0]))
#define CMDLENGTH 64
#define OUTSTRLEN 256

typedef struct {
  char *icon;
  char *command;
  unsigned int interval;
  unsigned int signal;
} Block;

void sighandler(int num);
void replace(char *str, char old, char new);
void getcmds(int time);
#ifndef __OpenBSD__
void getsigcmds(int signal);
void setupsignals();
void sighandler(int signum);
#endif
int getstatus(char *str, char *last);
void setroot();
void statusloop();
void termhandler(int signum);

#include "blocks.h"

static Display *dpy;
static int screen;
static Window root;
static char statusbar[LENGTH(blocks)][CMDLENGTH] = {0};
static char statusstr[2][OUTSTRLEN];
static int statusContinue = 1;
static void (*writestatus)() = setroot;

void replace(char *str, char old, char new) {
  int N = strlen(str);
  for (int i = 0; i < N; i++)
    if (str[i] == old)
      str[i] = new;
}

// opens process *cmd and stores output in *output
int getcmd(const Block *block, char *output) {
  char *cmd = block->command;
  char *ret = NULL;
  int status;
  char out[OUTSTRLEN];
  int outlen;
  int i = strlen(block->icon);
  FILE *cmdf = popen(cmd, "r");

  if (!cmdf)
    return (1);

  fgets(out, CMDLENGTH - i, cmdf);
  out[strcspn(out, "\n")] = 0;
  status = pclose(cmdf);

  // Only show block if exit status is good
  if (WIFEXITED(status) && WEXITSTATUS(status) == EXIT_SUCCESS) {
    asprintf(&ret, "%s%s%c", block->icon, out, delim);
    // printf("%s : %s\n", cmd, ret);
    memcpy(output, ret, strlen(ret));
    // printf("output: %s\n", output);
    free(ret);
    ret = NULL;
  } else {
    // printf("%s : returned %d\n", cmd, WEXITSTATUS(status));
    // empty the output for the block
    output[0] = 0;
    return (0);
  }
  return (1);
}

void getcmds(int time) {
  const Block *current;
  for (int i = 0; i < LENGTH(blocks); i++) {
    current = blocks + i;
    if ((current->interval != 0 && time % current->interval == 0) || time == -1)
      getcmd(current, statusbar[i]);
  }
}

#ifndef __OpenBSD__
void getsigcmds(int signal) {
  const Block *current;
  for (int i = 0; i < LENGTH(blocks); i++) {
    current = blocks + i;
    if (current->signal == signal)
      getcmd(current, statusbar[i]);
  }
}

void setupsignals() {
  for (int i = 0; i < LENGTH(blocks); i++) {
    if (blocks[i].signal > 0)
      signal(SIGRTMIN + blocks[i].signal, sighandler);
  }
}
#endif

int getstatus(char *str, char *last) {
  strcpy(last, str);
  str[0] = '\0';
  for (int i = 0; i < LENGTH(blocks); i++)
    strcat(str, statusbar[i]);
  str[strlen(str) - 1] = '\0';
  return strcmp(str, last); // 0 if they are the same
}

void setroot() {
  if (!getstatus(statusstr[0],
                 statusstr[1])) // Only set root if text has changed.
    return;
  Display *d = XOpenDisplay(NULL);
  if (d) {
    dpy = d;
  }
  screen = DefaultScreen(dpy);
  root = RootWindow(dpy, screen);
  XStoreName(dpy, root, statusstr[0]);
  XCloseDisplay(dpy);
  bzero((void *) statusstr, sizeof(statusstr));
  
}

void pstdout() {
  if (!getstatus(statusstr[0],
                 statusstr[1])) // Only write out if text has changed.
    return;
  printf("%s\n", statusstr[0]);
  fflush(stdout);
}

void statusloop() {
#ifndef __OpenBSD__
  setupsignals();
#endif
  int i = 0;
  getcmds(-1);
  while (statusContinue) {
    getcmds(i);
    writestatus();
    sleep(1.0);
    i++;
  }
}

#ifndef __OpenBSD__
void sighandler(int signum) {
  getsigcmds(signum - SIGRTMIN);
  writestatus();
}
#endif

void termhandler(int signum) {
  statusContinue = 0;
  exit(0);
}

int main(int argc, char **argv) {
  for (int i = 0; i < argc; i++) {
    if (!strcmp("-d", argv[i]))
      delim = argv[++i][0];
    else if (!strcmp("-p", argv[i]))
      writestatus = pstdout;
  }
  signal(SIGTERM, termhandler);
  signal(SIGINT, termhandler);
  statusloop();
}