commands over unix socket

[pandora_liveinfo.git] / main.c

/*
 * pandora live info
 * (C) notaz, 2014
 *
 * This work is licensed under the terms of 3-clause BSD license.
 * See COPYING file in the top-level directory.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <unistd.h>
#include <sys/time.h>
#include <time.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <signal.h>
#include <poll.h>
#include <linux/fb.h>
#include <linux/omapfb.h>
#include <stdint.h>
#include "fonts.h"

#define SCREEN_WIDTH 800
#define SCREEN_HEIGHT 480
#define WIDTH 80
#define HEIGHT 480
#define MEM_SIZE (((WIDTH * HEIGHT * 2 * 2) + 0xfff) & ~0xfff)
#define Y_STEP 9

static struct fb_var_screeninfo g_vi;
static uint16_t *g_screen_base, *g_screen;
static unsigned int g_old_mem;
static int g_flip_id;
static int g_exit, g_hide;
static pthread_cond_t g_cond;

#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
#define IS_START(buf, str) \
  !strncmp(buf, str, sizeof(str) - 1)

static void clear_bytes(void *mem, int bytes);

static int setup_layer(int fd)
{
  struct omapfb_plane_info pi;
  struct omapfb_mem_info mi;
  struct omapfb_color_key key;
  int ret;

  ret = ioctl(fd, OMAPFB_QUERY_PLANE, &pi);
  if (ret < 0) {
    perror("ioctl OMAPFB_QUERY_PLANE");
    return 1;
  }

  ret = ioctl(fd, OMAPFB_QUERY_MEM, &mi);
  if (ret < 0) {
    perror("ioctl OMAPFB_QUERY_MEM");
    return 1;
  }

  /* must disable when changing stuff */
  if (pi.enabled) {
    pi.enabled = 0;
    ret = ioctl(fd, OMAPFB_SETUP_PLANE, &pi);
    if (ret < 0) {
      perror("ioctl OMAPFB_SETUP_PLANE (d)");
      return 1;
    }
  }

  g_old_mem = mi.size;
  if (mi.size < MEM_SIZE) {
    mi.size = MEM_SIZE;
    ret = ioctl(fd, OMAPFB_SETUP_MEM, &mi);
    if (ret < 0) {
      perror("ioctl SETUP_MEM");
      return 1;
    }
  }

  pi.pos_x = SCREEN_WIDTH - WIDTH;
  pi.pos_y = 0;
  pi.out_width = WIDTH;
  pi.out_height = HEIGHT;
  ret = ioctl(fd, OMAPFB_SETUP_PLANE, &pi);
  if (ret < 0) {
    perror("ioctl OMAPFB_SETUP_PLANE (e1)");
    return 1;
  }

  ret = ioctl(fd, FBIOGET_VSCREENINFO, &g_vi);
  if (ret < 0) {
    perror("ioctl FBIOGET_VSCREENINFO");
    return 1;
  }

  g_vi.xres = g_vi.xres_virtual = WIDTH;
  g_vi.yres = HEIGHT;
  g_vi.yres_virtual = HEIGHT * 2;
  g_vi.bits_per_pixel = 16;

  ret = ioctl(fd, FBIOPUT_VSCREENINFO, &g_vi);
  if (ret < 0) {
    perror("ioctl FBIOPUT_VSCREENINFO");
    return 1;
  }

  pi.enabled = 1;
  ret = ioctl(fd, OMAPFB_SETUP_PLANE, &pi);
  if (ret < 0) {
    perror("ioctl OMAPFB_SETUP_PLANE (e2)");
    return 1;
  }

  memset(&key, 0, sizeof(key));
  key.key_type = OMAPFB_COLOR_KEY_VID_SRC;
  key.trans_key = 0x07e0;

  ret = ioctl(fd, OMAPFB_SET_COLOR_KEY, &key);
  if (ret < 0) {
    perror("ioctl OMAPFB_SET_COLOR_KEY");
    return 1;
  }

  g_screen_base = mmap(NULL, MEM_SIZE, PROT_READ | PROT_WRITE,
                  MAP_SHARED, fd, 0);
  if (g_screen_base == MAP_FAILED) {
    perror("mmap");
    g_screen = g_screen_base = NULL;
    return 1;
  }
  clear_bytes(g_screen_base, MEM_SIZE);
  g_screen = g_screen_base;
  g_flip_id = 0;

  return 0;
}

static int check_layer(int fd)
{
  struct omapfb_plane_info pi;
  int ret;

  ret = ioctl(fd, OMAPFB_QUERY_PLANE, &pi);
  if (ret < 0) {
    perror("ioctl OMAPFB_QUERY_PLANE");
    return 1;
  }

  if (!pi.enabled) {
    printf("something disabled the layer (tv-out?), quitting\n");
    return 1;
  }

  return 0;
}

static void remove_layer(int fd)
{
  struct omapfb_plane_info pi;
  struct omapfb_mem_info mi;
  int ret;

  if (g_screen_base != NULL) {
    munmap(g_screen_base, MEM_SIZE);
    g_screen = g_screen_base = NULL;
  }

  memset(&pi, 0, sizeof(pi));
  pi.enabled = 0;
  ret = ioctl(fd, OMAPFB_SETUP_PLANE, &pi);
  if (ret < 0)
    perror("ioctl OMAPFB_SETUP_PLANE (c)");

  ret = ioctl(fd, OMAPFB_QUERY_MEM, &mi);
  if (ret < 0) {
    perror("ioctl OMAPFB_QUERY_MEM");
    goto out;
  }

  if (mi.size != g_old_mem) {
    mi.size = g_old_mem;
    ret = ioctl(fd, OMAPFB_SETUP_MEM, &mi);
    if (ret < 0) {
      perror("ioctl SETUP_MEM");
      goto out;
    }
  }

out:;
}

static void flip_fb(int fd)
{
  g_vi.yoffset = g_flip_id * HEIGHT;
  ioctl(fd, FBIOPAN_DISPLAY, &g_vi);
  g_flip_id ^= 1;
  g_screen = g_screen_base + g_flip_id * WIDTH * HEIGHT;
}

static void handle_term(int num)
{
  g_exit = 1;
  pthread_cond_signal(&g_cond);
}

static void handle_usr1(int num)
{
  g_hide = !g_hide;
  pthread_cond_signal(&g_cond);
}

static struct {
  char text[16];
  int idle;
} user_msgs[16];

static int handle_socket(int sock)
{
  char buf[256], *p;
  int i, ret;

  ret = recv(sock, buf, sizeof(buf) - 1, 0);
  if (ret < 0) {
    perror("recv");
    return ret;
  }
  if (ret == 0)
    return 0;

  buf[ret] = 0;
  p = strchr(buf, ':');
  if (p != NULL) {
    for (i = 0; i < ARRAY_SIZE(user_msgs); i++) {
      if (user_msgs[i].text[0] == 0)
        break;
      if (!strncmp(user_msgs[i].text, buf, p - buf + 1))
        break;
    }
    if (i == ARRAY_SIZE(user_msgs)) {
      printf("out of user_msg slots\n");
      return 0;
    }
    memcpy(user_msgs[i].text, buf, sizeof(user_msgs[i].text) - 1);
    user_msgs[i].text[sizeof(user_msgs[i].text) - 1] = 0;
    user_msgs[i].idle = 0;
  }
  else if (!strcmp(buf, "poke")) {
    // if hidden, show up
    // if visible, exit
    if (g_hide) {
      g_hide = 0;
      return 1;
    }
    g_exit = 1;
    return 1;
  }
  else if (!strcmp(buf, "hide")) {
    g_hide = 1;
    return 1;
  }
  else if (!strcmp(buf, "show")) {
    g_hide = 0;
    return 1;
  }
  else if (!strcmp(buf, "quit")) {
    g_exit = 1;
    return 1;
  }
  else {
    printf("unknown command: '%s'\n", buf);
  }

  return 0;
}

#define s_printf(x, y, fmt, ...) \
  basic_text_out16(g_screen, WIDTH, x, y, fmt, ##__VA_ARGS__);

static int read_int_file(const char *fn, int *val)
{
  FILE *f;
  int ret;

  *val = 0;
  f = fopen(fn, "r");
  if (f == NULL)
    return 1;
  ret = fscanf(f, "%d", val);
  fclose(f);
  if (ret != 1)
    return 1;

  return 0;
}

static void clear_bytes(void *mem, int bytes)
{
  int *p = mem;
  int l = bytes / 4;

  for (; l >= 4; l -= 4, p += 4)
    p[0] = p[1] = p[2] = p[3] = 0x07e007e0;
  for (; l >  0; l--, p++)
    *p = 0x07e007e0;
}

static void clear(int h)
{
  clear_bytes(g_screen, WIDTH * h * 2);
}

struct proc_stat {
  unsigned long idlesum;
  unsigned long sys;
  unsigned long irqs;
  unsigned long ctxt;
};

static struct {
  struct proc_stat last_st;
  int cpu_usage;
  int cpu_sys;
  int irqs;
  int ctxt;
  int mem_free;
  int mem_huge;
  int mem_free_swap;
} stats;

static void collect_proc_stat(void)
{
  static long hz;
  struct proc_stat st;
  char buf[256];
  unsigned long wait;
  unsigned long iowait;
  FILE *f;

  if (hz == 0) {
    hz = sysconf(_SC_CLK_TCK);
    printf("hz: %ld\n", hz);
  }

  f = fopen("/proc/stat", "r");
  if (f == NULL)
    return;

  if (fscanf(f, "cpu %*s %*s %lu %lu %lu",
      &st.sys, &wait, &iowait) != 3)
    goto out;
  do {
    if (fgets(buf, sizeof(buf), f) == NULL)
      goto out;
  } while (fscanf(f, "intr %lu", &st.irqs) != 1);
  do {
    if (fgets(buf, sizeof(buf), f) == NULL)
      goto out;
  } while (fscanf(f, "ctxt %lu", &st.ctxt) != 1);

  st.idlesum = wait + iowait;

  stats.cpu_usage = hz - (st.idlesum - stats.last_st.idlesum);
  stats.cpu_sys = st.sys - stats.last_st.sys;
  if (hz != 100) {
    stats.cpu_usage = stats.cpu_usage * 100 / hz;
    stats.cpu_sys = stats.cpu_sys * 100 / hz;
  }
  stats.irqs = st.irqs - stats.last_st.irqs;
  stats.ctxt = st.ctxt - stats.last_st.ctxt;

out:
  stats.last_st = st;
  fclose(f);
}

static void collect_mem_stat(void)
{
  static const char fn[] = "/proc/meminfo";
  uint32_t total = 0, free = 0, buffers = 0, cached = 0;
  uint32_t anonhuge = 0, hugetot = 0, hugefree = 0, hugepgsz = 0;
  uint32_t free_swap = 0;
  char buf[128];
  FILE *f;

  f = fopen(fn, "r");
  if (f == NULL)
    return;

  while (fgets(buf, sizeof(buf), f)) {
    if (total == 0 && sscanf(buf, "MemTotal: %u", &total) == 1)
      continue;
    if (free == 0 && sscanf(buf, "MemFree: %u", &free) == 1)
      continue;
    if (buffers == 0 && sscanf(buf, "Buffers: %u", &buffers) == 1)
      continue;
    if (cached == 0 && sscanf(buf, "Cached: %u", &cached) == 1)
      continue;
    if (free_swap == 0 && sscanf(buf, "SwapFree: %u", &free_swap) == 1)
      continue;
    if (anonhuge == 0 && sscanf(buf, "AnonHugePages: %u", &anonhuge) == 1)
      continue;
    if (hugetot == 0 && sscanf(buf, "HugePages_Total: %u", &hugetot) == 1)
      continue;
    if (hugefree == 0 && sscanf(buf, "HugePages_Free: %u", &hugefree) == 1)
      continue;
    if (hugepgsz == 0 && sscanf(buf, "Hugepagesize: %u", &hugepgsz) == 1)
      continue;
  }

  fclose(f);

  hugetot = (hugetot - hugefree) * hugepgsz;
  free += buffers + cached;
  stats.mem_free = free >> 10;
  stats.mem_huge = hugetot >> 10;
  stats.mem_free_swap = free_swap >> 10;
}

struct io_stat {
  unsigned long sec_r;
  unsigned long sec_w;
};

static struct {
  struct io_stat last_st;
  int read; // kB/s
  int write;
} io_stats;

static void collect_io_stat(void)
{
  unsigned long sec_r, sec_w;
  struct io_stat st = { 0, };
  char buf[128];
  FILE *f;
  int i;

  for (i = 0; i < 2; i++) {
    snprintf(buf, sizeof(buf), "/sys/block/mmcblk%d/stat", i);
    f = fopen(buf, "r");
    if (f == NULL)
      continue;

    if (fscanf(f, "%*s %*s %lu %*s %*s %*s %lu",
               &sec_r, &sec_w) == 2)
    {
      st.sec_r += sec_r;
      st.sec_w += sec_w;
    }
    fclose(f);
  }

  io_stats.read = st.sec_r - io_stats.last_st.sec_r;
  io_stats.write = st.sec_w - io_stats.last_st.sec_w;
  // assuming 512 byte sectors..
  io_stats.read >>= 1;
  io_stats.write >>= 1;

  io_stats.last_st = st;
}

struct net_stat {
  unsigned long rx;
  unsigned long tx;
};

static struct {
  struct net_stat last_st;
  int down; // kB/s
  int up;
  int have_wlan;
  int link;
  int level;
} net_stats;

static void collect_net_stat(void)
{
  struct net_stat st = { 0, };
  unsigned long rx, tx;
  int found = 0;
  char buf[256];
  FILE *f;

  net_stats.down = net_stats.up =
  net_stats.have_wlan = net_stats.link = net_stats.level = 0;

  f = fopen("/proc/net/dev", "r");
  if (f == NULL)
    return;

  while (!feof(f)) {
    static const char fmt[] =
      "%255s %lu %*s %*s %*s %*s %*s %*s %lu";
    if (fscanf(f, fmt, buf, &rx, &tx) != 3)
      continue;
    if (IS_START(buf, "lo"))
      continue;
    st.rx += rx;
    st.tx += tx;
    found = 1;
  }
  fclose(f);

  if (found) {
    net_stats.down = st.rx - net_stats.last_st.rx;
    net_stats.up = st.tx - net_stats.last_st.tx;
  }
  net_stats.last_st = st;

  f = fopen("/proc/net/wireless", "r");
  if (f == NULL)
    return;

  while (!feof(f)) {
    int lnk, lvl;
    if (fscanf(f, "%255s %*x %d. %d.", buf, &lnk, &lvl) != 3)
      continue;
    if (IS_START(buf, "lo"))
      continue;
    // first one should be enough
    net_stats.have_wlan = 1;
    net_stats.link = lnk;
    net_stats.level = lvl;
    break;
  }
  fclose(f);
}

static void collect_stats(void)
{
  collect_proc_stat();
  collect_mem_stat();
  collect_io_stat();
  collect_net_stat();
}

static char cpu_reg_path[64];

static void init_stats(void)
{
  char buf[64];
  int found;
  FILE *f;
  int i;

  // find the CPU regulator
  for (i = found = 0; ; i++) {
    snprintf(buf, sizeof(buf),
      "/sys/class/regulator/regulator.%d/name", i);
    f = fopen(buf, "r");
    if (f == NULL)
      break;
    fgets(buf, sizeof(buf), f);
    fclose(f);
    if (IS_START(buf, "vdd_mpu")) {
      found = 1;
      break;
    }
  }

  if (found)
    snprintf(cpu_reg_path, sizeof(cpu_reg_path),
      "/sys/class/regulator/regulator.%d/microvolts", i);

  // do collect so differential stats get sane values
  collect_stats();
}

static void get_time(int x, int y)
{
  struct timeval tv;
  struct tm *t;
  char buf[16];

  gettimeofday(&tv, NULL);
  t = localtime(&tv.tv_sec);
  strftime(buf, sizeof(buf), "%T", t);
  s_printf(x, y, " %s", buf);
}

static void get_cpu(int x, int y)
{
  s_printf(x, y, "CPU:%5d%%", stats.cpu_usage);
}

static void get_sys(int x, int y)
{
  s_printf(x, y, "SYS:%5d%%", stats.cpu_sys);
}

static void get_irq(int x, int y)
{
  s_printf(x, y, "IRQ:%5u", stats.irqs);
}

static void get_cs(int x, int y)
{
  s_printf(x, y, "CS:%6u", stats.ctxt);
}

static void get_cpuf(int x, int y)
{
  static const char fn[] =
    "/sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq";
  int f;

  if (read_int_file(fn, &f))
    return;
  s_printf(x, y, "f:%7dM", f / 1000);
}

static void get_cpuv(int x, int y)
{
  int v = 0;

  if (!cpu_reg_path[0] || read_int_file(cpu_reg_path, &v))
    return;
  s_printf(x, y, "V:%7.3fV", (float)v / 1000000.0f);
}

static void get_memfree(int x, int y)
{
  s_printf(x, y, "M:%7dM", stats.mem_free);
}

static void get_memhuge(int x, int y)
{
  s_printf(x, y, "H:%7dM", stats.mem_huge);
}

static void get_memswap(int x, int y)
{
  s_printf(x, y, "S:%7dM", stats.mem_free_swap);
}

#define PS_BASE "/sys/class/power_supply/bq27500-0/"

static void get_bcap(int x, int y)
{
  static const char fnc[] = PS_BASE "capacity";
  int c;

  if (read_int_file(fnc, &c))
    return;
  s_printf(x, y, "C:%7d%%", c);
}

static void get_btime(int x, int y)
{
  static const char fne[] = PS_BASE "time_to_empty_now";
  static const char fnf[] = PS_BASE "time_to_full_now";
  int t = 0;

  if (read_int_file(fne, &t) || t == 0) {
    if (read_int_file(fnf, &t))
      return;
  }
  s_printf(x, y, "t:%4d:%02d", t / 3600, t / 60 % 60);
}

static void get_bvolts(int x, int y)
{
  static const char fnv[] = PS_BASE "voltage_now";
  int volt = 0;

  if (read_int_file(fnv, &volt))
    return;

  s_printf(x, y, "V:%7.3fV", (float)volt / 1000000.0f);
}

static void get_bwatts(int x, int y)
{
  static const char fnc[] = PS_BASE "current_now";
  static const char fnv[] = PS_BASE "voltage_now";
  int w, cur = 0, volt = 0;

  if (read_int_file(fnc, &cur))
    return;
  if (read_int_file(fnv, &volt))
    return;

  w = (cur / 1000) * (volt / 1000);
  s_printf(x, y, "P:%7.3fW", (float)w / 1000000.0f);
}

static void get_btemp(int x, int y)
{
  static const char fnt[] = PS_BASE "temp";
  int t;

  if (read_int_file(fnt, &t))
    return;
  s_printf(x, y, "T:%7.1fC", (float)t / 10.0f);
}

static void get_ioread(int x, int y)
{
  s_printf(x, y, "R:%5.1fM/s", (float)io_stats.read / 1000.0f);
}

static void get_iowrite(int x, int y)
{
  s_printf(x, y, "W:%5.1fM/s", (float)io_stats.write / 1000.0f);
}

static void get_netdown(int x, int y)
{
  s_printf(x, y, "D:%5uK/s", net_stats.down / 1000);
}

static void get_netup(int x, int y)
{
  s_printf(x, y, "U:%5uK/s", net_stats.up / 1000);
}

static void get_netsgnl(int x, int y)
{
  s_printf(x, y, "S:%5ddBm", net_stats.level);
}

int main(int argc, char *argv[])
{
  static const char socket_name[] = "\0liveinfo";
  static const char fbname[] = "/dev/fb2";
  pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
  pthread_condattr_t condattr;
  struct sockaddr_un sun;
  struct timespec ts;
  struct pollfd pfd;
  const char *p;
  int is_hidden = 0;
  int y = 0, y_max = 0;
  int fd = -1;
  int sock;
  int i, ret;

  // look for other instance
  sock = socket(PF_UNIX, SOCK_DGRAM, 0);
  if (sock == -1) {
    perror("socket PF_UNIX");
    return 1;
  }

  memset(&sun, 0, sizeof(sun));
  sun.sun_family = AF_UNIX;
  memcpy(sun.sun_path, socket_name, sizeof(socket_name));

  ret = connect(sock, (struct sockaddr *)&sun, sizeof(sun));
  if (ret == 0) {
    printf("other instance detected, sending poke command\n");
    ret = send(sock, "poke", 4, 0);
    if (ret != 4)
      perror("send");
    close(sock);
    return ret == 4 ? 0 : 1;
  }

  fd = open(fbname, O_RDWR);
  if (fd == -1) {
    fprintf(stderr, "open %s: ", fbname);
    perror(NULL);
    return 1;
  }

  nice(-1);

  // no need for privileges any more
  p = getenv("SUDO_UID");
  if (p != NULL) {
    ret = atoi(p);
    if (ret != 0) {
      ret = setuid(ret);
      if (ret)
        perror("setuid");
    }
  }

  // bind/listen for commands
  ret = bind(sock, (struct sockaddr *)&sun, sizeof(sun));
  if (ret != 0) {
    perror("bind");
    close(sock);
    return 1;
  }

#if 0
  ret = listen(sock, 1);
  if (ret != 0) {
    perror("listen");
    close(sock);
    return 1;
  }
#endif

  pfd.fd = sock;
  pfd.events = POLLIN | POLLPRI;
  pfd.revents = 0;

  ret  = pthread_condattr_init(&condattr);
  ret |= pthread_condattr_setclock(&condattr, CLOCK_MONOTONIC);
  ret |= pthread_cond_init(&g_cond, &condattr);
  pthread_condattr_destroy(&condattr);
  if (ret != 0) {
    fprintf(stderr, "cond init failed\n");
    return 1;
  }

  ret = setup_layer(fd);
  if (ret)
    return ret;

  // clean up on kill too
  signal(SIGTERM, handle_term);
  signal(SIGUSR1, handle_usr1);

  pthread_mutex_lock(&mutex);
  ret = clock_gettime(CLOCK_MONOTONIC, &ts);
  if (ret != 0) {
    perror("clock_gettime CLOCK_MONOTONIC");
    return 1;
  }

  init_stats();

  while (!g_exit)
  {
    // anything on unix socket?
    ret = poll(&pfd, 1, 0);
    if (ret < 0) {
      perror("poll");
      break;
    }
    if (ret > 0) {
      ret = handle_socket(sock);
      if (ret < 0)
        break;
      continue;
    }

    // handle hiding
    if (g_hide) {
      if (!is_hidden) {
        remove_layer(fd);
        is_hidden = 1;
      }
      goto do_sleep;
    }
    else if (is_hidden) {
      ret = setup_layer(fd);
      if (ret)
        break;
      is_hidden = 0;
    }

    if (check_layer(fd) != 0)
      break;

    collect_stats();

    y += Y_STEP;
    if (y > y_max)
      y_max = y;
    clear(y_max);

    y = 0;
    get_time   (0, y += Y_STEP);
    y += Y_STEP / 2;
    get_cpu    (0, y += Y_STEP);
    get_sys    (0, y += Y_STEP);
    get_irq    (0, y += Y_STEP);
    get_cs     (0, y += Y_STEP);
    get_cpuf   (0, y += Y_STEP);
    get_cpuv   (0, y += Y_STEP);
    y += Y_STEP / 2;
    s_printf(0, y += Y_STEP, "mem");
    get_memfree(0, y += Y_STEP);
    get_memswap(0, y += Y_STEP);
    if (stats.mem_huge)
      get_memhuge(0, y += Y_STEP);
    y += Y_STEP / 2;
    s_printf(0, y += Y_STEP, "i/o");
    get_ioread (0, y += Y_STEP);
    get_iowrite(0, y += Y_STEP);
    y += Y_STEP / 2;
    s_printf(0, y += Y_STEP, "net");
    get_netdown(0, y += Y_STEP);
    get_netup  (0, y += Y_STEP);
    if (net_stats.have_wlan)
      get_netsgnl(0, y += Y_STEP);
    y += Y_STEP / 2;
    s_printf(0, y += Y_STEP, "batt");
    get_bcap   (0, y += Y_STEP);
    get_btime  (0, y += Y_STEP);
    get_bvolts (0, y += Y_STEP);
    get_bwatts (0, y += Y_STEP);
    get_btemp  (0, y += Y_STEP);

    // print user messages
    y += Y_STEP;
    for (i = 0; i < ARRAY_SIZE(user_msgs); i++) {
      if (user_msgs[i].text[0] == 0)
        break;
      user_msgs[i].idle++;
      if (user_msgs[i].idle > 6) {
        // drop old entry, shift others up
        memmove(&user_msgs[i], &user_msgs[i + 1],
          (ARRAY_SIZE(user_msgs) - i - 1) * sizeof(user_msgs[0]));
        user_msgs[ARRAY_SIZE(user_msgs) - 1].text[0] = 0;
        // reprocess
        i--;
        continue;
      }

      s_printf(0, y += Y_STEP, user_msgs[i].text);
    }

    flip_fb(fd);

do_sleep:
    ts.tv_sec++;
    pthread_cond_timedwait(&g_cond, &mutex, &ts);
  }

  remove_layer(fd);
  close(fd);
  close(sock);

  return 0;
}

// vim:expandtab:sw=2:ts=2