path: root/src/io.c

/*
 * Calcurse - text-based organizer
 *
 * Copyright (c) 2004-2012 calcurse Development Team <misc@calcurse.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the
 *        following disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the
 *        following disclaimer in the documentation and/or other
 *        materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Send your feedback or comments to : misc@calcurse.org
 * Calcurse home page : http://calcurse.org
 *
 */

#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <signal.h>
#include <time.h>
#include <math.h>
#include <unistd.h>
#include <errno.h>

#include "calcurse.h"
#include "sha1.h"

typedef enum {
  PROGRESS_BAR_SAVE,
  PROGRESS_BAR_LOAD,
  PROGRESS_BAR_EXPORT
} progress_bar_t;

enum {
  PROGRESS_BAR_CONF,
  PROGRESS_BAR_TODO,
  PROGRESS_BAR_APTS,
  PROGRESS_BAR_KEYS
};

enum {
  PROGRESS_BAR_EXPORT_EVENTS,
  PROGRESS_BAR_EXPORT_APOINTS,
  PROGRESS_BAR_EXPORT_TODO
};

struct ht_keybindings_s {
  const char *label;
  enum key key;
   HTABLE_ENTRY(ht_keybindings_s);
};

static void load_keys_ht_getkey(struct ht_keybindings_s *, const char **,
                                int *);
static int load_keys_ht_compare(struct ht_keybindings_s *,
                                struct ht_keybindings_s *);

#define HSIZE 256
HTABLE_HEAD(ht_keybindings, HSIZE, ht_keybindings_s);
HTABLE_PROTOTYPE(ht_keybindings, ht_keybindings_s)
    HTABLE_GENERATE(ht_keybindings, ht_keybindings_s, load_keys_ht_getkey,
                load_keys_ht_compare)

/* Draw a progress bar while saving, loading or exporting data. */
static void progress_bar(progress_bar_t type, int progress)
{
#define NBFILES		4
#define NBEXPORTED      3
#define LABELENGTH      15
  int i, step, steps;
  const char *mesg_sav = _("Saving...");
  const char *mesg_load = _("Loading...");
  const char *mesg_export = _("Exporting...");
  const char *error_msg = _("Internal error while displaying progress bar");
  const char *barchar = "|";
  const char *file[NBFILES] = {
    "[    conf    ]",
    "[    todo    ]",
    "[    apts    ]",
    "[    keys    ]"
  };
  const char *data[NBEXPORTED] = {
    "[   events   ]",
    "[appointments]",
    "[    todo    ]"
  };
  int ipos = LABELENGTH + 2;
  int epos[NBFILES];

  /* progress bar length init. */
  ipos = LABELENGTH + 2;
  steps = (type == PROGRESS_BAR_EXPORT) ? NBEXPORTED : NBFILES;
  step = floor(col / (steps + 1));
  for (i = 0; i < steps - 1; i++)
    epos[i] = (i + 2) * step;
  epos[steps - 1] = col - 2;

  switch (type) {
  case PROGRESS_BAR_SAVE:
    EXIT_IF(progress < 0 || progress > PROGRESS_BAR_KEYS, "%s", error_msg);
    status_mesg(mesg_sav, file[progress]);
    break;
  case PROGRESS_BAR_LOAD:
    EXIT_IF(progress < 0 || progress > PROGRESS_BAR_KEYS, "%s", error_msg);
    status_mesg(mesg_load, file[progress]);
    break;
  case PROGRESS_BAR_EXPORT:
    EXIT_IF(progress < 0
            || progress > PROGRESS_BAR_EXPORT_TODO, "%s", error_msg);
    status_mesg(mesg_export, data[progress]);
    break;
  }

  /* Draw the progress bar. */
  mvwaddstr(win[STA].p, 1, ipos, barchar);
  mvwaddstr(win[STA].p, 1, epos[steps - 1], barchar);
  custom_apply_attr(win[STA].p, ATTR_HIGHEST);
  for (i = ipos + 1; i < epos[progress]; i++)
    mvwaddch(win[STA].p, 1, i, ' ' | A_REVERSE);
  custom_remove_attr(win[STA].p, ATTR_HIGHEST);
  wmove(win[STA].p, 0, 0);
  wins_wrefresh(win[STA].p);
#undef NBFILES
#undef NBEXPORTED
#undef LABELENGTH
}

/* Ask user for a file name to export data to. */
static FILE *get_export_stream(enum export_type type)
{
  FILE *stream;
  char *home, *stream_name;
  const char *question = _("Choose the file used to export calcurse data:");
  const char *wrong_name =
      _("The file cannot be accessed, please enter another file name.");
  const char *press_enter = _("Press [ENTER] to continue.");
  const char *file_ext[IO_EXPORT_NBTYPES] = { "ical", "txt" };

  stream = NULL;
  stream_name = (char *)mem_malloc(BUFSIZ);
  if ((home = getenv("HOME")) != NULL)
    snprintf(stream_name, BUFSIZ, "%s/calcurse.%s", home, file_ext[type]);
  else
    snprintf(stream_name, BUFSIZ, "%s/calcurse.%s", get_tempdir(),
             file_ext[type]);

  while (stream == NULL) {
    status_mesg(question, "");
    if (updatestring(win[STA].p, &stream_name, 0, 1)) {
      mem_free(stream_name);
      return NULL;
    }
    stream = fopen(stream_name, "w");
    if (stream == NULL) {
      status_mesg(wrong_name, press_enter);
      wgetch(win[STA].p);
    }
  }
  mem_free(stream_name);

  return stream;
}

/* Append a line to a file. */
unsigned io_fprintln(const char *fname, const char *fmt, ...)
{
  FILE *fp;
  va_list ap;
  char buf[BUFSIZ];
  int ret;

  fp = fopen(fname, "a");
  RETVAL_IF(!fp, 0, _("Failed to open \"%s\", - %s\n"), fname, strerror(errno));

  va_start(ap, fmt);
  ret = vsnprintf(buf, sizeof buf, fmt, ap);
  RETVAL_IF(ret < 0, 0, _("Failed to build message\n"));
  va_end(ap);

  ret = fprintf(fp, "%s", buf);
  RETVAL_IF(ret < 0, 0, _("Failed to print message \"%s\"\n"), buf);

  ret = fclose(fp);
  RETVAL_IF(ret != 0, 0, _("Failed to close \"%s\" - %s\n"),
            fname, strerror(errno));

  return 1;
}

/*
 * Initialization of data paths. The cfile argument is the variable
 * which contains the calendar file. If none is given, then the default
 * one (~/.calcurse/apts) is taken. If the one given does not exist, it
 * is created.
 * The datadir argument can be use to specify an alternative data root dir.
 */
void io_init(const char *cfile, const char *datadir)
{
  FILE *data_file;
  const char *home;
  char apts_file[BUFSIZ] = "";
  int ch;

  if (datadir != NULL) {
    home = datadir;
    snprintf(path_dir, BUFSIZ, "%s", home);
    snprintf(path_todo, BUFSIZ, "%s/" TODO_PATH_NAME, home);
    snprintf(path_conf, BUFSIZ, "%s/" CONF_PATH_NAME, home);
    snprintf(path_notes, BUFSIZ, "%s/" NOTES_DIR_NAME, home);
    snprintf(path_keys, BUFSIZ, "%s/" KEYS_PATH_NAME, home);
    snprintf(path_cpid, BUFSIZ, "%s/" CPID_PATH_NAME, home);
    snprintf(path_dpid, BUFSIZ, "%s/" DPID_PATH_NAME, home);
    snprintf(path_dmon_log, BUFSIZ, "%s/" DLOG_PATH_NAME, home);
  } else {
    home = getenv("HOME");
    if (home == NULL) {
      home = ".";
    }
    snprintf(path_dir, BUFSIZ, "%s/" DIR_NAME, home);
    snprintf(path_todo, BUFSIZ, "%s/" TODO_PATH, home);
    snprintf(path_conf, BUFSIZ, "%s/" CONF_PATH, home);
    snprintf(path_keys, BUFSIZ, "%s/" KEYS_PATH, home);
    snprintf(path_cpid, BUFSIZ, "%s/" CPID_PATH, home);
    snprintf(path_dpid, BUFSIZ, "%s/" DPID_PATH, home);
    snprintf(path_dmon_log, BUFSIZ, "%s/" DLOG_PATH, home);
    snprintf(path_notes, BUFSIZ, "%s/" NOTES_DIR, home);
  }

  if (cfile == NULL) {
    if (datadir != NULL) {
      snprintf(path_apts, BUFSIZ, "%s/" APTS_PATH_NAME, home);
    } else {
      snprintf(path_apts, BUFSIZ, "%s/" APTS_PATH, home);
    }
  } else {
    snprintf(apts_file, BUFSIZ, "%s", cfile);
    strncpy(path_apts, apts_file, BUFSIZ);
    /* check if the file exists, otherwise create it */
    data_file = fopen(path_apts, "r");
    if (data_file == NULL) {
      printf(_("%s does not exist, create it now [y or n] ? "), path_apts);
      ch = getchar();
      switch (ch) {
      case 'N':
      case 'n':
        puts(_("aborting...\n"));
        exit_calcurse(EXIT_FAILURE);
        break;

      case 'Y':
      case 'y':
        data_file = fopen(path_apts, "w");
        if (data_file == NULL) {
          perror(path_apts);
          exit_calcurse(EXIT_FAILURE);
        } else {
          printf(_("%s successfully created\n"), path_apts);
          puts(_("starting interactive mode...\n"));
        }
        break;

      default:
        puts(_("aborting...\n"));
        exit_calcurse(EXIT_FAILURE);
        break;
      }
    }
    file_close(data_file, __FILE_POS__);
  }
}

void io_extract_data(char *dst_data, const char *org, int len)
{
  int i;

  for (; *org == ' ' || *org == '\t'; org++) ;
  for (i = 0; i < len - 1; i++) {
    if (*org == '\n' || *org == '\0' || *org == '#')
      break;
    *dst_data++ = *org++;
  }
  *dst_data = '\0';
}

static pthread_mutex_t io_save_mutex = PTHREAD_MUTEX_INITIALIZER;

/*
 * Save the apts data file, which contains the
 * appointments first, and then the events.
 * Recursive items are written first.
 */
unsigned io_save_apts(void)
{
  llist_item_t *i;
  FILE *fp;

  if (read_only)
    return 1;

  if ((fp = fopen(path_apts, "w")) == NULL)
    return 0;

  recur_save_data(fp);

  if (ui_mode == UI_CURSES)
    LLIST_TS_LOCK(&alist_p);
  LLIST_TS_FOREACH(&alist_p, i) {
    struct apoint *apt = LLIST_TS_GET_DATA(i);
    apoint_write(apt, fp);
  }
  if (ui_mode == UI_CURSES)
    LLIST_TS_UNLOCK(&alist_p);

  LLIST_FOREACH(&eventlist, i) {
    struct event *ev = LLIST_TS_GET_DATA(i);
    event_write(ev, fp);
  }
  file_close(fp, __FILE_POS__);

  return 1;
}

/* Save the todo data file. */
unsigned io_save_todo(void)
{
  llist_item_t *i;
  FILE *fp;

  if (read_only)
    return 1;

  if ((fp = fopen(path_todo, "w")) == NULL)
    return 0;

  LLIST_FOREACH(&todolist, i) {
    struct todo *todo = LLIST_TS_GET_DATA(i);
    todo_write(todo, fp);
  }
  file_close(fp, __FILE_POS__);

  return 1;
}

/* Save user-defined keys */
unsigned io_save_keys(void)
{
  FILE *fp;

  if (read_only)
    return 1;

  if ((fp = fopen(path_keys, "w")) == NULL)
    return 0;

  keys_save_bindings(fp);
  file_close(fp, __FILE_POS__);

  return 1;
}

/* Save the calendar data */
void io_save_cal(enum save_display display)
{
  const char *access_pb = _("Problems accessing data file ...");
  const char *save_success = _("The data files were successfully saved");
  const char *enter = _("Press [ENTER] to continue");
  int show_bar;

  if (read_only)
    return;

  pthread_mutex_lock(&io_save_mutex);

  show_bar = 0;
  if (ui_mode == UI_CURSES && display == IO_SAVE_DISPLAY_BAR
      && conf.progress_bar)
    show_bar = 1;

  if (show_bar)
    progress_bar(PROGRESS_BAR_SAVE, PROGRESS_BAR_CONF);
  if (!config_save())
    ERROR_MSG("%s", access_pb);

  if (show_bar)
    progress_bar(PROGRESS_BAR_SAVE, PROGRESS_BAR_TODO);
  if (!io_save_todo())
    ERROR_MSG("%s", access_pb);

  if (show_bar)
    progress_bar(PROGRESS_BAR_SAVE, PROGRESS_BAR_APTS);
  if (!io_save_apts())
    ERROR_MSG("%s", access_pb);

  if (show_bar)
    progress_bar(PROGRESS_BAR_SAVE, PROGRESS_BAR_KEYS);
  if (!io_save_keys())
    ERROR_MSG("%s", access_pb);

  /* Print a message telling data were saved */
  if (ui_mode == UI_CURSES && conf.system_dialogs) {
    status_mesg(save_success, enter);
    wgetch(win[STA].p);
  }

  pthread_mutex_unlock(&io_save_mutex);
}

static void io_load_error(const char *filename, unsigned line,
                          const char *mesg)
{
  EXIT("%s:%u: %s", filename, line, mesg);
}

/*
 * Check what type of data is written in the appointment file,
 * and then load either: a new appointment, a new event, or a new
 * recursive item (which can also be either an event or an appointment).
 */
void io_load_app(void)
{
  FILE *data_file;
  int c, is_appointment, is_event, is_recursive;
  struct tm start, end, until, lt;
  llist_t exc;
  time_t t;
  int id = 0;
  int freq;
  char type, state = 0L;
  char note[MAX_NOTESIZ + 1], *notep;
  unsigned line = 0;

  t = time(NULL);
  localtime_r(&t, &lt);
  start = end = until = lt;

  data_file = fopen(path_apts, "r");
  EXIT_IF(data_file == NULL, _("failed to open appointment file"));

  for (;;) {
    LLIST_INIT(&exc);
    is_appointment = is_event = is_recursive = 0;
    line++;
    c = getc(data_file);
    if (c == EOF)
      break;
    ungetc(c, data_file);

    /* Read the date first: it is common to both events
     * and appointments.
     */
    if (fscanf(data_file, "%d / %d / %d ",
               &start.tm_mon, &start.tm_mday, &start.tm_year) != 3)
      io_load_error(path_apts, line, _("syntax error in the item date"));

    /* Read the next character : if it is an '@' then we have
     * an appointment, else if it is an '[' we have en event.
     */
    c = getc(data_file);

    if (c == '@')
      is_appointment = 1;
    else if (c == '[')
      is_event = 1;
    else
      io_load_error(path_apts, line, _("no event nor appointment found"));

    /* Read the remaining informations. */
    if (is_appointment) {
      if (fscanf(data_file, " %d : %d -> %d / %d / %d @ %d : %d ",
                 &start.tm_hour, &start.tm_min,
                 &end.tm_mon, &end.tm_mday, &end.tm_year,
                 &end.tm_hour, &end.tm_min) != 7)
        io_load_error(path_apts, line,
                      _("syntax error in item time or duration"));
    } else if (is_event) {
      if (fscanf(data_file, " %d ", &id) != 1 || getc(data_file) != ']')
        io_load_error(path_apts, line, _("syntax error in item identifier"));
      while ((c = getc(data_file)) == ' ') ;
      ungetc(c, data_file);
    } else {
      io_load_error(path_apts, line,
                    _("wrong format in the appointment or event"));
      /* NOTREACHED */
    }

    /* Check if we have a recursive item. */
    c = getc(data_file);

    if (c == '{') {
      is_recursive = 1;
      if (fscanf(data_file, " %d%c ", &freq, &type) != 2)
        io_load_error(path_apts, line, _("syntax error in item repetition"));

      c = getc(data_file);
      if (c == '}') {           /* endless recurrent item */
        until.tm_year = 0;
        while ((c = getc(data_file)) == ' ') ;
        ungetc(c, data_file);
      } else if (c == '-' && getc(data_file) == '>') {
        if (fscanf(data_file, " %d / %d / %d ", &until.tm_mon,
                   &until.tm_mday, &until.tm_year) != 3)
          io_load_error(path_apts, line, _("syntax error in item repetition"));
        c = getc(data_file);
        if (c == '!') {
          ungetc(c, data_file);
          recur_exc_scan(&exc, data_file);
          c = getc(data_file);
        } else if (c == '}') {
          while ((c = getc(data_file)) == ' ') ;
          ungetc(c, data_file);
        } else
          io_load_error(path_apts, line, _("syntax error in item repetition"));
      } else if (c == '!') {    /* endless item with exceptions */
        ungetc(c, data_file);
        recur_exc_scan(&exc, data_file);
        c = getc(data_file);
        until.tm_year = 0;
      } else {
        io_load_error(path_apts, line,
                      _("wrong format in the appointment or event"));
        /* NOTREACHED */
      }
    } else
      ungetc(c, data_file);

    /* Check if a note is attached to the item. */
    c = getc(data_file);
    if (c == '>') {
      note_read(note, data_file);
      notep = note;
    } else {
      notep = NULL;
      ungetc(c, data_file);
    }

    /*
     * Last: read the item description and load it into its
     * corresponding linked list, depending on the item type.
     */
    if (is_appointment) {
      c = getc(data_file);
      if (c == '!') {
        state |= APOINT_NOTIFY;
        while ((c = getc(data_file)) == ' ') ;
        ungetc(c, data_file);
      } else if (c == '|') {
        state = 0L;
        while ((c = getc(data_file)) == ' ') ;
        ungetc(c, data_file);
      } else
        io_load_error(path_apts, line, _("syntax error in item repetition"));
      if (is_recursive) {
        recur_apoint_scan(data_file, start, end,
                          type, freq, until, notep, &exc, state);
      } else {
        apoint_scan(data_file, start, end, state, notep);
      }
    } else if (is_event) {
      if (is_recursive) {
        recur_event_scan(data_file, start, id, type, freq, until, notep, &exc);
      } else {
        event_scan(data_file, start, id, notep);
      }
    } else {
      io_load_error(path_apts, line,
                    _("wrong format in the appointment or event"));
      /* NOTREACHED */
    }
  }
  file_close(data_file, __FILE_POS__);
}

/* Load the todo data */
void io_load_todo(void)
{
  FILE *data_file;
  char *newline;
  int nb_tod = 0;
  int c, id;
  char buf[BUFSIZ], e_todo[BUFSIZ], note[MAX_NOTESIZ + 1];
  unsigned line = 0;

  data_file = fopen(path_todo, "r");
  EXIT_IF(data_file == NULL, _("failed to open todo file"));

  for (;;) {
    line++;
    c = getc(data_file);
    if (c == EOF)
      break;
    else if (c == '[') {        /* new style with id */
      if (fscanf(data_file, " %d ", &id) != 1 || getc(data_file) != ']')
        io_load_error(path_todo, line, _("syntax error in item identifier"));
      while ((c = getc(data_file)) == ' ') ;
      ungetc(c, data_file);
    } else {
      id = 9;
      ungetc(c, data_file);
    }
    /* Now read the attached note, if any. */
    c = getc(data_file);
    if (c == '>')
      note_read(note, data_file);
    else {
      note[0] = '\0';
      ungetc(c, data_file);
    }
    /* Then read todo description. */
    if (!fgets(buf, sizeof buf, data_file))
      buf[0] = '\0';
    newline = strchr(buf, '\n');
    if (newline)
      *newline = '\0';
    io_extract_data(e_todo, buf, sizeof buf);
    todo_add(e_todo, id, note);
    ++nb_tod;
  }
  file_close(data_file, __FILE_POS__);
  todo_set_nb(nb_tod);
}

static void
load_keys_ht_getkey(struct ht_keybindings_s *data, const char **key, int *len)
{
  *key = data->label;
  *len = strlen(data->label);
}

static int
load_keys_ht_compare(struct ht_keybindings_s *data1,
                     struct ht_keybindings_s *data2)
{
  const int KEYLEN = strlen(data1->label);

  if (strlen(data2->label) == KEYLEN
      && !memcmp(data1->label, data2->label, KEYLEN))
    return 0;
  else
    return 1;
}

/*
 * isblank(3) is protected by the __BSD_VISIBLE macro and this fails to be
 * visible in some specific cases. Thus replace it by the following is_blank()
 * function.
 */
static int is_blank(int c)
{
  return c == ' ' || c == '\t';
}

/*
 * Load user-definable keys from file.
 * A hash table is used to speed up loading process in avoiding string
 * comparisons.
 * A log file is also built in case some errors were found in the key
 * configuration file.
 */
void io_load_keys(const char *pager)
{
  struct ht_keybindings_s keys[NBKEYS];
  FILE *keyfp;
  char buf[BUFSIZ];
  struct io_file *log;
  int i, skipped, loaded, line;
  const int MAX_ERRORS = 5;

  keys_init();

  struct ht_keybindings ht_keys = HTABLE_INITIALIZER(&ht_keys);

  for (i = 0; i < NBKEYS; i++) {
    keys[i].key = (enum key)i;
    keys[i].label = keys_get_label((enum key)i);
    HTABLE_INSERT(ht_keybindings, &ht_keys, &keys[i]);
  }

  keyfp = fopen(path_keys, "r");
  EXIT_IF(keyfp == NULL, _("failed to open key file"));

  log = io_log_init();
  skipped = loaded = line = 0;
  while (fgets(buf, BUFSIZ, keyfp) != NULL) {
    char key_label[BUFSIZ], *p;
    struct ht_keybindings_s *ht_elm, ht_entry;
    const int AWAITED = 1;
    int assigned;

    line++;
    if (skipped > MAX_ERRORS) {
      const char *too_many =
          _("\nToo many errors while reading configuration file!\n"
            "Please backup your keys file, remove it from directory, "
            "and launch calcurse again.\n");

      io_log_print(log, line, too_many);
      break;
    }
    for (p = buf; is_blank((int)*p); p++) ;
    if (p != buf)
      memmove(buf, p, strlen(p));
    if (buf[0] == '#' || buf[0] == '\n')
      continue;

    if (sscanf(buf, "%s", key_label) != AWAITED) {
      skipped++;
      io_log_print(log, line, _("Could not read key label"));
      continue;
    }
    ht_entry.label = key_label;
    p = buf + strlen(key_label) + 1;
    ht_elm = HTABLE_LOOKUP(ht_keybindings, &ht_keys, &ht_entry);
    if (!ht_elm) {
      skipped++;
      io_log_print(log, line, _("Key label not recognized"));
      continue;
    }
    assigned = 0;
    for (;;) {
      char key_ch[BUFSIZ], tmpbuf[BUFSIZ];

      while (*p == ' ')
        p++;
      (void)strncpy(tmpbuf, p, BUFSIZ);
      if (sscanf(tmpbuf, "%s", key_ch) == AWAITED) {
        int ch;

        if ((ch = keys_str2int(key_ch)) < 0) {
          char unknown_key[BUFSIZ];

          skipped++;
          (void)snprintf(unknown_key, BUFSIZ,
                         _("Error reading key: \"%s\""), key_ch);
          io_log_print(log, line, unknown_key);
        } else {
          int used;

          used = keys_assign_binding(ch, ht_elm->key);
          if (used) {
            char already_assigned[BUFSIZ];

            skipped++;
            (void)snprintf(already_assigned, BUFSIZ,
                           _("\"%s\" assigned multiple times!"), key_ch);
            io_log_print(log, line, already_assigned);
          } else
            assigned++;
        }
        p += strlen(key_ch) + 1;
      } else {
        if (assigned)
          loaded++;
        break;
      }
    }
  }
  file_close(keyfp, __FILE_POS__);
  file_close(log->fd, __FILE_POS__);
  if (skipped > 0) {
    const char *view_log =
        _("There were some errors when loading keys file, see log file ?");

    io_log_display(log, view_log, pager);
  }
  io_log_free(log);
  EXIT_IF(skipped > MAX_ERRORS,
          _("Too many errors while reading keys file, aborting..."));
  if (loaded < NBKEYS)
    keys_fill_missing();
  if (keys_check_missing_bindings())
    WARN_MSG(_("Some actions do not have any associated key bindings!"));
}

int io_check_dir(const char *dir)
{
  if (read_only)
    return -1;

  errno = 0;
  if (mkdir(dir, 0700) != 0) {
    if (errno != EEXIST) {
      fprintf(stderr, _("FATAL ERROR: could not create %s: %s\n"), dir,
              strerror(errno));
      exit_calcurse(EXIT_FAILURE);
    } else {
      return 1;
    }
  } else {
    return 0;
  }
}

unsigned io_file_exist(const char *file)
{
  FILE *fd;

  if (file && (fd = fopen(file, "r")) != NULL) {
    fclose(fd);
    return 1;
  }
  else {
    return 0;
  }
}

int io_check_file(const char *file)
{
  if (read_only)
    return -1;

  errno = 0;
  if (io_file_exist(file)) {
    return 1;
  } else {
    FILE *fd;

    if ((fd = fopen(file, "w")) == NULL) {
      fprintf(stderr, _("FATAL ERROR: could not create %s: %s\n"), file,
              strerror(errno));
      exit_calcurse(EXIT_FAILURE);
    }
    file_close(fd, __FILE_POS__);

    return 0;
  }
}

/*
 * Checks if data files exist. If not, create them.
 * The following structure has to be created:
 *
 *	$HOME/.calcurse/
 *                 |
 *                 +--- notes/
 *                 |___ conf
 *                 |___ keys
 *                 |___ apts
 *                 |___ todo
 */
int io_check_data_files(void)
{
  int missing = 0;

  missing += io_check_dir(path_dir) ? 0 : 1;
  missing += io_check_dir(path_notes) ? 0 : 1;
  missing += io_check_file(path_todo) ? 0 : 1;
  missing += io_check_file(path_apts) ? 0 : 1;
  missing += io_check_file(path_conf) ? 0 : 1;

  if (!io_check_file(path_keys)) {
    missing++;
    keys_dump_defaults(path_keys);
  }

  return missing;
}

/* Draw the startup screen */
void io_startup_screen(int no_data_file)
{
  const char *enter = _("Press [ENTER] to continue");

  if (no_data_file)
    status_mesg(_("Data files found. Data will be loaded now."), enter);
  else
    status_mesg(_("Welcome to Calcurse. Missing data files were created."),
                enter);

  wgetch(win[STA].p);
}

/* Export calcurse data. */
void io_export_data(enum export_type type)
{
  FILE *stream = NULL;
  const char *success = _("The data were successfully exported");
  const char *enter = _("Press [ENTER] to continue");

  if (type < IO_EXPORT_ICAL || type >= IO_EXPORT_NBTYPES)
    EXIT(_("unknown export type"));

  switch (ui_mode) {
  case UI_CMDLINE:
    stream = stdout;
    break;
  case UI_CURSES:
    stream = get_export_stream(type);
    break;
  default:
    EXIT(_("wrong export mode"));
    /* NOTREACHED */
  }

  if (stream == NULL)
    return;

  if (type == IO_EXPORT_ICAL)
    ical_export_data(stream);
  else if (type == IO_EXPORT_PCAL)
    pcal_export_data(stream);

  if (conf.system_dialogs && ui_mode == UI_CURSES) {
    status_mesg(success, enter);
    wgetch(win[STA].p);
  }
}

static FILE *get_import_stream(enum export_type type)
{
  FILE *stream = NULL;
  char *stream_name;
  const char *ask_fname = _("Enter the file name to import data from:");
  const char *wrong_file =
      _("The file cannot be accessed, please enter another file name.");
  const char *press_enter = _("Press [ENTER] to continue.");

  stream_name = mem_malloc(BUFSIZ);
  memset(stream_name, 0, BUFSIZ);
  while (stream == NULL) {
    status_mesg(ask_fname, "");
    if (updatestring(win[STA].p, &stream_name, 0, 1)) {
      mem_free(stream_name);
      return NULL;
    }
    stream = fopen(stream_name, "r");
    if (stream == NULL) {
      status_mesg(wrong_file, press_enter);
      wgetch(win[STA].p);
    }
  }
  mem_free(stream_name);

  return stream;
}

/*
 * Import data from a given stream (either stdin in non-interactive mode, or the
 * user given file in interactive mode).
 * A temporary log file is created in /tmp to store the import process report,
 * and is cleared at the end.
 */
void io_import_data(enum import_type type, const char *stream_name)
{
  const char *proc_report = _("Import process report: %04d lines read ");
  char stats_str[4][BUFSIZ];
  FILE *stream = NULL;
  struct io_file *log;
  struct {
    unsigned events, apoints, todos, lines, skipped;
  } stats;

  EXIT_IF(type < 0 || type >= IO_IMPORT_NBTYPES, _("unknown import type"));
  switch (ui_mode) {
  case UI_CMDLINE:
    stream = fopen(stream_name, "r");
    EXIT_IF(stream == NULL,
            _("FATAL ERROR: the input file cannot be accessed, "
              "Aborting..."));
    break;
  case UI_CURSES:
    stream = get_import_stream(type);
    break;
  default:
    EXIT(_("FATAL ERROR: wrong import mode"));
    /* NOTREACHED */
  }

  if (stream == NULL)
    return;

  memset(&stats, 0, sizeof stats);

  log = io_log_init();
  if (log == NULL) {
    if (stream != stdin)
      file_close(stream, __FILE_POS__);
    return;
  }

  if (type == IO_IMPORT_ICAL)
    ical_import_data(stream, log->fd, &stats.events, &stats.apoints,
                     &stats.todos, &stats.lines, &stats.skipped);

  if (stream != stdin)
    file_close(stream, __FILE_POS__);

  snprintf(stats_str[0], BUFSIZ,
           ngettext("%d app", "%d apps", stats.apoints), stats.apoints);
  snprintf(stats_str[1], BUFSIZ,
           ngettext("%d event", "%d events", stats.events), stats.events);
  snprintf(stats_str[2], BUFSIZ,
           ngettext("%d todo", "%d todos", stats.todos), stats.todos);
  snprintf(stats_str[3], BUFSIZ, _("%d skipped"), stats.skipped);

  /* Update the number of todo items. */
  todo_set_nb(todo_nb() + stats.todos);

  if (ui_mode == UI_CURSES && conf.system_dialogs) {
    char read[BUFSIZ], stat[BUFSIZ];

    snprintf(read, BUFSIZ, proc_report, stats.lines);
    snprintf(stat, BUFSIZ, "%s / %s / %s / %s (%s)", stats_str[0],
             stats_str[1], stats_str[2], stats_str[3],
             _("Press [ENTER] to continue"));
    status_mesg(read, stat);
    wgetch(win[STA].p);
  } else if (ui_mode == UI_CMDLINE) {
    printf(proc_report, stats.lines);
    printf("\n%s / %s / %s / %s\n", stats_str[0], stats_str[1],
           stats_str[2], stats_str[3]);
  }

  /* User has the choice to look at the log file if some items could not be
     imported.
   */
  file_close(log->fd, __FILE_POS__);
  if (stats.skipped > 0) {
    const char *view_log =
        _("Some items could not be imported, see log file ?");

    io_log_display(log, view_log, conf.pager);
  }
  io_log_free(log);
}

struct io_file *io_log_init(void)
{
  char logprefix[BUFSIZ];
  char *logname;
  struct io_file *log;

  snprintf(logprefix, BUFSIZ, "%s/calcurse_log.", get_tempdir());
  logname = new_tempfile(logprefix, TMPEXTSIZ);
  RETVAL_IF(logname == NULL, 0,
            _("Warning: could not create temporary log file, Aborting..."));
  log = mem_malloc(sizeof(struct io_file));
  RETVAL_IF(log == NULL, 0,
            _("Warning: could not open temporary log file, Aborting..."));
  snprintf(log->name, sizeof(log->name), "%s%s", logprefix, logname);
  mem_free(logname);
  log->fd = fopen(log->name, "w");
  if (log->fd == NULL) {
    ERROR_MSG(_("Warning: could not open temporary log file, Aborting..."));
    mem_free(log);
    return 0;
  }

  return log;
}

void io_log_print(struct io_file *log, int line, const char *msg)
{
  if (log && log->fd)
    fprintf(log->fd, "line %d: %s\n", line, msg);
}

void io_log_display(struct io_file *log, const char *msg, const char *pager)
{
  RETURN_IF(log == NULL, _("No log file to display!"));
  if (ui_mode == UI_CMDLINE) {
    printf("\n%s [y/n] ", msg);
    if (fgetc(stdin) == 'y') {
      const char *arg[] = { pager, log->name, NULL };
      int pid;

      if ((pid = fork_exec(NULL, NULL, pager, arg)))
        child_wait(NULL, NULL, pid);
    }
  } else {
    if (status_ask_bool(msg) == 1)
      wins_launch_external(log->name, pager);
    wins_erase_status_bar();
  }
}

void io_log_free(struct io_file *log)
{
  if (!log)
    return;
  EXIT_IF(unlink(log->name) != 0,
          _("Warning: could not erase temporary log file %s, Aborting..."),
          log->name);
  mem_free(log);
}

static pthread_t io_t_psave;

/* Thread used to periodically save data. */
static void *io_psave_thread(void *arg)
{
  int delay = conf.periodic_save;
  EXIT_IF(delay < 0, _("Invalid delay"));

  for (;;) {
    sleep(delay * MININSEC);
    io_save_cal(IO_SAVE_DISPLAY_NONE);
  }
}

/* Launch the thread which handles periodic saves. */
void io_start_psave_thread(void)
{
  pthread_create(&io_t_psave, NULL, io_psave_thread, NULL);
}

/* Stop periodic data saves. */
void io_stop_psave_thread(void)
{
  if (io_t_psave) {
    pthread_cancel(io_t_psave);
    pthread_join(io_t_psave, NULL);
  }
}

/*
 * This sets a lock file to prevent from having two different instances of
 * calcurse running.
 *
 * If the lock cannot be obtained, then warn the user and exit calcurse. Else,
 * create a .calcurse.pid file in the user defined directory, which will be
 * removed when calcurse exits.
 *
 * Note: When creating the lock file, the interactive mode is not initialized
 * yet.
 */
void io_set_lock(void)
{
  FILE *lock = fopen(path_cpid, "r");
  int pid;

  if (lock != NULL) {
    /* If there is a lock file, check whether the process exists. */
    if (fscanf(lock, "%d", &pid) == 1) {
      fclose(lock);
      if (kill(pid, 0) != 0 && errno == ESRCH)
        lock = NULL;
    } else
      fclose(lock);
  }

  if (lock != NULL) {
    fprintf(stderr,
            _("\nWARNING: it seems that another calcurse instance is "
              "already running.\n"
              "If this is not the case, please remove the following "
              "lock file: \n\"%s\"\n" "and restart calcurse.\n"), path_cpid);
    exit(EXIT_FAILURE);
  } else {
    if (!io_dump_pid(path_cpid))
      EXIT(_("FATAL ERROR: could not create %s: %s\n"),
           path_cpid, strerror(errno));
  }
}

/*
 * Create a new file and write the process pid inside (used to create a simple
 * lock for example). Overwrite already existing files.
 */
unsigned io_dump_pid(char *file)
{
  pid_t pid;
  FILE *fp;

  if (!file)
    return 0;

  pid = getpid();
  if (!(fp = fopen(file, "w"))
      || fprintf(fp, "%ld\n", (long)pid) < 0 || fclose(fp) != 0)
    return 0;

  return 1;
}

/*
 * Return the pid number contained in a file previously created with
 * io_dump_pid ().
 * If no file was found, return 0.
 */
unsigned io_get_pid(char *file)
{
  FILE *fp;
  unsigned pid;

  if (!file)
    return 0;

  if ((fp = fopen(file, "r")) == NULL)
    return 0;

  if (fscanf(fp, "%u", &pid) != 1)
    return 0;

  fclose(fp);

  return pid;
}

/*
 * Check whether a file is empty.
 */
int io_file_is_empty(char *file)
{
  FILE *fp;

  if (file && (fp = fopen(file, "r"))) {
    if ((fgetc(fp) == '\n' && fgetc(fp) == EOF) || feof(fp)) {
      fclose(fp);
      return 1;
    } else {
      fclose(fp);
      return 0;
    }
  }

  return -1;
}

/*
 * Copy an existing file to a new location.
 */
int io_file_cp(const char *src, const char *dst)
{
  FILE *fp_src, *fp_dst;
  char *buffer[BUFSIZ];
  unsigned int bytes_read;

  if (!(fp_src = fopen(src, "rb")))
    return 0;
  if (!(fp_dst = fopen(dst, "wb")))
    return 0;

  while (!feof(fp_src)) {
    bytes_read = fread(buffer, 1, BUFSIZ, fp_src);
    if (bytes_read > 0) {
      if (fwrite(buffer, 1, bytes_read, fp_dst) != bytes_read)
        return 0;
    } else
      return 0;
  }

  fclose(fp_dst);
  fclose(fp_src);

  return 1;
}