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=head1 NAME

rifle - ranger's file opener




=head1 SYNOPSIS

B<rifle> [B<--help>] [B<-f> I<FLAGS>] [B<-l>] [B<-p> I<KEYWORD>]
[B<-w> I<PROGRAM>] I<files>




=head1 DESCRIPTION

rifle is a powerful file executor that allows for complex file type checking,
written to meet the needs of the file manager I<ranger>.  rifle's strength lies
in automatically determining file types, depending on which programs are
installed on the system, even without any user interaction.




=head1 OPTIONS

=over 14

=item B<-f> I<FLAGS>

Specify flags for opening the files.  Flags are letters that changes how the
program is executed.  Any combination of flags will work.  Writing uppercase
flags will negate the effect of all previously used lowercase flags of the same
letter.

Table of all flags:
 f   fork program to background
 r   run program as root, using sudo
 t   run program in a separate terminal, as specified by $TERMCMD

=item B<-l>

List all possible ways to open the specified files.  Each line will contain information in the format of I<id:label:flags:command>. I<id> is the identification number. I<label> is an arbitrary string that was specified for this command, I<flags> are the flags that are used by default, and I<command> is the command that is going to be executed.

=item B<-p> I<KEYWORD>

Pick a method to open the files.

I<KEYWORD> is either the ID number listed by C<rifle -l> or a string that matches a label in the configuration file.

=item B<-w> I<PROGRAM>

Open the files with the program I<PROGRAM>

=item B<-h>, B<--help>

Print a list of options and exit.

=back




=head1 FILES

rifle shares configuration files with ranger, though ranger is not required in
order to use rifle.  The configuration file F<rifle.conf> is expected to be at
F<~/.config/ranger/rifle.conf>.

This file specifies patterns for determining the commands to open files with.
The syntax is described in the comments of the default F<rifle.conf> that ships
with ranger.  To obtain it, you need to run: C<ranger --copy-config=rifle>




=head1 ENVIRONMENT

=over 8

=item EDITOR

Determines which editor to use for editing files (in the default F<rifle.conf>).

=item PAGER

Determines which pager to use for displaying files (in the default F<rifle.conf>).

=item TERMCMD

Determines the terminal emulator command for use with the I<t> flag.  It is required that the value is the path to an executable file which accepts the "-e COMMAND" argument.

=item XDG_CONFIG_HOME

Specifies the directory for configuration files. Defaults to F<$HOME/.config>.

=back




=head1 EXAMPLES

List all the different methods:

 $ rifle -l helloworld.py
 0:editor::"$EDITOR" -- "$@"
 1:pager::"$PAGER" -- "$@"
 2:::python -- "$1"

Display its content by opening it with "cat":

 $ rifle -w cat helloworld.py
 print("Hello World!")

Run it by picking the method 2, which calls 'python -- "$1"':

 $ rifle -p 2 helloworld.py
 Hello World!

Display the file in a pager inside a new terminal, run as root:

 $ rifle -p 1 -f tr helloworld.py
ss='alt'>
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#include <assert.h>
#include <ctype.h>
#include <ncurses.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "lua.h"
#include "lauxlib.h"
#include "teliva.h"
#include "tlv.h"

/*** Standard UI elements */

int menu_column = 0;

void draw_string_on_menu(const char* s) {
  mvaddstr(LINES-1, menu_column, " ");
  ++menu_column;
  mvaddstr(LINES-1, menu_column, s);
  menu_column += strlen(s);
  mvaddstr(LINES-1, menu_column, " ");
  ++menu_column;
}

void draw_menu_item(const char* key, const char* name) {
  attroff(A_REVERSE);
  draw_string_on_menu(key);
  attron(A_REVERSE);
  draw_string_on_menu(name);
}

static void render_permissions(lua_State* L);
char* Previous_message;
static void draw_menu(lua_State* L) {
  attron(A_BOLD|A_REVERSE);
  color_set(COLOR_PAIR_MENU, NULL);
  for (int x = 0; x < COLS; ++x)
    mvaddch(LINES-1, x, ' ');
  menu_column = 2;
  draw_menu_item("^x", "exit");
  draw_menu_item("^e", "edit");
  draw_menu_item("^p", "perms");

  /* if app ran successfully, render any app-specific items */
  if (Previous_message == NULL) {
    lua_getglobal(L, "menu");
    int table = lua_gettop(L);
    if (lua_istable(L, -1)) {
      for (int i = 1; i <= luaL_getn(L, table); ++i) {
        lua_rawgeti(L, table, i);
        int menu_item = lua_gettop(L);
        lua_rawgeti(L, menu_item, 1);  /* key */
        lua_rawgeti(L, menu_item, 2);  /* value */
        draw_menu_item(lua_tostring(L, -2), lua_tostring(L, -1));
        lua_pop(L, 3);
      }
    }
    lua_pop(L, 1);
  }
  else {
    /* otherwise render the flash message */
    attron(COLOR_PAIR(COLOR_PAIR_ERROR));
    addstr(Previous_message);
    attroff(COLOR_PAIR(COLOR_PAIR_ERROR));
  }

  /* render app permissions on the right */
  render_permissions(L);

  attrset(A_NORMAL);
}

static void render_permissions(lua_State* L) {
  attrset(A_NORMAL);
  mvaddstr(LINES-1, COLS-12, "");
  int file_colors = file_operations_allowed ? COLOR_PAIR_WARN : COLOR_PAIR_SAFE;
  int net_colors = net_operations_allowed ? COLOR_PAIR_WARN : COLOR_PAIR_SAFE;
  if (file_operations_allowed && net_operations_allowed) {
    file_colors = net_colors = COLOR_PAIR_RISK;
  }

  attron(COLOR_PAIR(file_colors));
  addstr("file ");
  attron(A_REVERSE);
  addstr(" ");
  attroff(COLOR_PAIR(file_colors));

  attron(COLOR_PAIR(net_colors));
  addstr(" ");
  attroff(A_REVERSE);
  addstr(" net");
  attroff(COLOR_PAIR(net_colors));
}

void render_trusted_teliva_data(lua_State* L) {
  init_pair(COLOR_PAIR_ERROR, COLOR_ERROR_FOREGROUND, COLOR_ERROR_BACKGROUND);
  init_pair(COLOR_PAIR_MENU, COLOR_FOREGROUND, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_SAFE, COLOR_SAFE_REVERSE, COLOR_FOREGROUND);
  init_pair(COLOR_PAIR_WARN, COLOR_WARN_REVERSE, COLOR_FOREGROUND);
  init_pair(COLOR_PAIR_RISK, COLOR_RISK_REVERSE, COLOR_FOREGROUND);
  draw_menu(L);
}

/*** Error reporting */

const char* Previous_error = NULL;

/* return final y containing text */
static int render_wrapped_text(int y, int xmin, int xmax, const char* text) {
  int x = xmin;
  move(y, x);
  for (int j = 0; j < strlen(text); ++j) {
    char c = text[j];
    if (c != '\n') {
      addch(text[j]);
      ++x;
      if (x >= xmax) {
        ++y;
        x = xmin;
        move(y, x);
      }
    }
    else {
      /* newline */
      ++y;
      x = xmin;
      move(y, x);
    }
  }
  return y;
}

void render_previous_error(void) {
  if (!Previous_error) return;
  init_pair(COLOR_PAIR_ERROR, COLOR_ERROR_FOREGROUND, COLOR_ERROR_BACKGROUND);
  attron(COLOR_PAIR(COLOR_PAIR_ERROR));
  render_wrapped_text(LINES-10, COLS/2, COLS, Previous_error);
  attroff(COLOR_PAIR(COLOR_PAIR_ERROR));
}

extern char* strdup(const char* s);
int report_in_developer_mode(lua_State* L, int status) {
  if (status && !lua_isnil(L, -1)) {
    Previous_error = strdup(lua_tostring(L, -1));  /* memory leak */
    if (Previous_error == NULL) Previous_error = "(error object is not a string)";
    lua_pop(L, 1);
    for (int x = 0; x < COLS; ++x) {
      mvaddch(LINES-2, x, ' ');
      mvaddch(LINES-1, x, ' ');
    }
    render_previous_error();
    mvaddstr(LINES-1, 0, "press any key to continue");
    getch();
    developer_mode(L);
  }
  return status;
}

/*** Developer mode, big picture view */

#define CURRENT_DEFINITION_LEN 256

static void big_picture_menu(void) {
  attrset(A_REVERSE);
  for (int x = 0; x < COLS; ++x)
    mvaddch(LINES-1, x, ' ');
  attrset(A_NORMAL);
  menu_column = 2;
  draw_menu_item("^x", "go back");
  draw_menu_item("^g", "go to highlight");
  draw_menu_item("Enter", "submit");
  draw_menu_item("^h", "backspace");
  draw_menu_item("^u", "clear");
  draw_menu_item("^r", "recent changes");
  attrset(A_NORMAL);
}

static int is_current_definition(lua_State* L, const char* definition_name, int current_history_array_index, int history_array_location, int history_array_size) {
  /* Sequentially scan back through history_array until current_history_array_index.
   * Is there an earlier definition of definition_name? */
  int oldtop = lua_gettop(L);
  int found = 0;
  for (int i = history_array_size; i > current_history_array_index; --i) {
    lua_rawgeti(L, history_array_location, i);
    int t = lua_gettop(L);
    for (lua_pushnil(L); lua_next(L, t) != 0;) {
      lua_pop(L, 1);  // value
      const char* curr = lua_tostring(L, -1);
      if (strcmp(curr, definition_name) == 0) {
        found = 1;
        lua_pop(L, 1); // key
        break;
      }
      // leave key on stack for next iteration
    }
    lua_pop(L, 1);  // history element
    if (found)
      break;
  }
  if(oldtop != lua_gettop(L)) {
    endwin();
    printf("%d %d\n", oldtop, lua_gettop(L));
    exit(1);
  }
  return !found;
}

void draw_definition_name(const char* definition_name) {
  attron(COLOR_PAIR(COLOR_PAIR_SELECTABLE));
  addstr(" ");
  addstr(definition_name);
  addstr(" ");
  attroff(COLOR_PAIR(COLOR_PAIR_SELECTABLE));
  addstr("  ");
}

void draw_highlighted_definition_name(const char* definition_name) {
  attron(A_REVERSE);
  addstr(" ");
  addstr(definition_name);
  addstr(" ");
  attroff(A_REVERSE);
  addstr("  ");
}

/* return true if submitted */
static int edit_current_definition(lua_State* L);
static void recent_changes_view(lua_State* L);
void big_picture_view(lua_State* L) {
  /* Without any intervening edits, big_picture_view always stably renders
   * definitions in exactly the same spatial order, both in levels from top to
   * bottom and in indexes within each level from left to right. */
  int highlight_level = 0;
  int highlight_index_within_level = 0;
  int level_size[30] = {0};  /* number of indexes within each level */
  char highlight[CURRENT_DEFINITION_LEN+1] = {0};
restart:
  clear();
  luaL_newmetatable(L, "__teliva_call_graph_depth");
  int cgt = lua_gettop(L);
  // special-case: we don't instrument the call to main, but it's always at depth 1
  lua_pushinteger(L, 1);
  lua_setfield(L, cgt, "main");
  // segment definitions by depth
  lua_getglobal(L, "teliva_program");
  int history_array = lua_gettop(L);
  int history_array_size = luaL_getn(L, history_array);

  int y = 1;
  attrset(A_BOLD);
  mvaddstr(y, 0, "Big picture");
  attrset(A_NORMAL);
  y += 2;
  mvaddstr(y, 0, "data:           ");
  // first: data (non-functions) that's not the Teliva menu or curses variables
  if (highlight_level < 0) highlight_level = 0;
  int level = 0;
  int index_within_level = 0;
  for (int i = history_array_size; i > 0; --i) {
    lua_rawgeti(L, history_array, i);
    int t = lua_gettop(L);
    for (lua_pushnil(L); lua_next(L, t) != 0; lua_pop(L, 1)) {
      const char* definition_name = lua_tostring(L, -2);
      if (is_special_history_key(definition_name)) continue;
      lua_getglobal(L, definition_name);
      int is_userdata = lua_isuserdata(L, -1);
      int is_function = lua_isfunction(L, -1);
      lua_pop(L, 1);
      if (strcmp(definition_name, "menu") != 0  // required by all Teliva programs
          && !is_function  // functions are not data
          && !is_userdata  // including curses window objects
                           // (unlikely to have an interesting definition)
      ) {
        if (is_current_definition(L, definition_name, i, history_array, history_array_size)) {
          if (level == highlight_level && index_within_level == highlight_index_within_level) {
            draw_highlighted_definition_name(definition_name);
            strncpy(highlight, definition_name, CURRENT_DEFINITION_LEN);
          } else {
            draw_definition_name(definition_name);
          }
          ++index_within_level;
        }
      }
    }
    lua_pop(L, 1);  // history element
  }

  // second: menu and other userdata
  for (int i = history_array_size; i > 0; --i) {
    lua_rawgeti(L, history_array, i);
    int t = lua_gettop(L);
    for (lua_pushnil(L); lua_next(L, t) != 0; lua_pop(L, 1)) {
      const char* definition_name = lua_tostring(L, -2);
      if (is_special_history_key(definition_name)) continue;
      lua_getglobal(L, definition_name);
      int is_userdata = lua_isuserdata(L, -1);
      lua_pop(L, 1);
      if (strcmp(definition_name, "menu") == 0
          || is_userdata  // including curses window objects
      ) {
        if (is_current_definition(L, definition_name, i, history_array, history_array_size)) {
          if (level == highlight_level && index_within_level == highlight_index_within_level) {
            draw_highlighted_definition_name(definition_name);
            strncpy(highlight, definition_name, CURRENT_DEFINITION_LEN);
          } else {
            draw_definition_name(definition_name);
          }
          ++index_within_level;
        }
      }
    }
    lua_pop(L, 1);  // history element
  }
  level_size[level] = index_within_level;
  level++;

  // functions by level
  y += 2;
  mvprintw(y, 0, "functions: ");
  y++;
  for (int depth = 1; ; ++depth) {
    mvaddstr(y, 0, "                ");
    bool drew_anything = false;
    index_within_level = 0;
    for (int i = history_array_size; i > 0; --i) {
      lua_rawgeti(L, history_array, i);
      int t = lua_gettop(L);
      for (lua_pushnil(L); lua_next(L, t) != 0; lua_pop(L, 1)) {
        const char* definition_name = lua_tostring(L, -2);
        if (is_special_history_key(definition_name)) continue;
        lua_getfield(L, cgt, definition_name);
        int definition_depth = lua_tointeger(L, -1);
        if (definition_depth == depth) {
          if (is_current_definition(L, definition_name, i, history_array, history_array_size)) {
            if (level == highlight_level && index_within_level == highlight_index_within_level) {
              draw_highlighted_definition_name(definition_name);
              strncpy(highlight, definition_name, CURRENT_DEFINITION_LEN);
            } else {
              draw_definition_name(definition_name);
            }
            ++index_within_level;
          }
          drew_anything = true;
        }
        lua_pop(L, 1);  // depth of value
      }
      lua_pop(L, 1);  // history element
    }
    y += 2;
    if (!drew_anything) break;
    level_size[level] = index_within_level;
    level++;
  }

  // unused functions
  mvaddstr(y, 0, "                ");
  /* no need to level++ because the final iteration above didn't draw anything */
  index_within_level = 0;
  for (int i = history_array_size; i > 0; --i) {
    lua_rawgeti(L, history_array, i);
    int t = lua_gettop(L);
    for (lua_pushnil(L); lua_next(L, t) != 0; lua_pop(L, 1)) {
      const char* definition_name = lua_tostring(L, -2);
      if (is_special_history_key(definition_name)) continue;
      lua_getglobal(L, definition_name);
      int is_function = lua_isfunction(L, -1);
      lua_pop(L, 1);
      lua_getfield(L, cgt, definition_name);
      if (is_function && lua_isnoneornil(L, -1)) {
        if (is_current_definition(L, definition_name, i, history_array, history_array_size)) {
          if (level == highlight_level && index_within_level == highlight_index_within_level) {
            draw_highlighted_definition_name(definition_name);
            strncpy(highlight, definition_name, CURRENT_DEFINITION_LEN);
          } else {
            draw_definition_name(definition_name);
          }
          ++index_within_level;
        }
      }
      lua_pop(L, 1);  // depth of value
    }
    lua_pop(L, 1);  // history element
  }
  level_size[level] = index_within_level;
  int max_level = level;

  lua_settop(L, 0);
  render_previous_error();

  char query[CURRENT_DEFINITION_LEN+1] = {0};
  int qlen = 0;
  while (1) {
    big_picture_menu();
    for (int x = 0; x < COLS; ++x)
      mvaddch(LINES-2, x, ' ');
//?     mvprintw(20, 60, "%d %d\n", highlight_level, highlight_index_within_level);
    mvprintw(LINES-2, 0, "Edit: %s", query);
    int c = getch();
    if (c == KEY_BACKSPACE || c == DELETE || c == CTRL_H) {
      if (qlen != 0) query[--qlen] = '\0';
    } else if (c == CTRL_X) {
      return;
    } else if (c == ENTER) {
      if (query[0] != '\0') {
        save_to_current_definition_and_editor_buffer(L, query);
        int back_to_big_picture = edit_current_definition(L);
        if (back_to_big_picture) goto restart;
        return;
      }
    } else if (c == CTRL_U) {
      qlen = 0;
      query[qlen] = '\0';
    } else if (c == CTRL_R) {
      recent_changes_view(L);
      goto restart;
    } else if (c == KEY_LEFT) {
      highlight_index_within_level--;
      if (highlight_index_within_level < 0) highlight_index_within_level = 0;
      goto restart;
    } else if (c == KEY_RIGHT) {
      highlight_index_within_level++;
      if (highlight_index_within_level >= level_size[highlight_level])
        highlight_index_within_level = level_size[highlight_level]-1;
      if (highlight_index_within_level < 0) highlight_index_within_level = 0;
      goto restart;
    } else if (c == KEY_UP) {
      highlight_level--;
      if (highlight_level < 0) highlight_level = 0;
      if (highlight_index_within_level >= level_size[highlight_level])
        highlight_index_within_level = level_size[highlight_level]-1;
      if (highlight_index_within_level < 0) highlight_index_within_level = 0;
      goto restart;
    } else if (c == KEY_DOWN) {
      highlight_level++;
      if (highlight_level > max_level) highlight_level = max_level;
      if (highlight_index_within_level >= level_size[highlight_level])
        highlight_index_within_level = level_size[highlight_level]-1;
      if (highlight_index_within_level < 0) highlight_index_within_level = 0;
      goto restart;
    } else if (c == CTRL_G) {
      save_to_current_definition_and_editor_buffer(L, highlight);
      int back_to_big_picture = edit_current_definition(L);
      if (back_to_big_picture) goto restart;
      return;
    } else if (isprint(c)) {
      if (qlen < CURRENT_DEFINITION_LEN) {
          query[qlen++] = c;
          query[qlen] = '\0';
      }
    }
  }
  /* never gets here */
}

/* return true if:
 *  - editor_state exists, and
 *  - editor_state is applicable to the current image
 * Implicitly loads current editor state. */
int editor_view_in_progress(lua_State* L) {
  FILE* in = fopen("teliva_editor_state", "r");
  if (in == NULL) return 0;
  int oldtop = lua_gettop(L);
  teliva_load_definition(L, in);
  int t = lua_gettop(L);
  lua_getfield(L, t, "image");
  const char* image_name  = lua_tostring(L, -1);
  int result = (strcmp(image_name, Image_name) == 0);
  lua_pop(L, 1);  /* image value */
  lua_setglobal(L, "__teliva_editor_state");
  assert(lua_gettop(L) == oldtop);
  return result;
}

extern int load_editor_buffer_to_current_definition_in_image(lua_State* L);
extern int resumeEdit(lua_State* L);
extern int edit_from(lua_State* L, char* filename, int rowoff, int coloff, int cy, int cx);
int restore_editor_view(lua_State* L) {
  lua_getglobal(L, "__teliva_editor_state");
  int editor_state_index = lua_gettop(L);
  lua_getfield(L, editor_state_index, "definition");
  const char* definition = lua_tostring(L, -1);
  save_to_current_definition_and_editor_buffer(L, definition);
  lua_getfield(L, editor_state_index, "rowoff");
  int rowoff = lua_tointeger(L, -1);
  lua_getfield(L, editor_state_index, "coloff");
  int coloff = lua_tointeger(L, -1);
  lua_getfield(L, editor_state_index, "cy");
  int cy = lua_tointeger(L, -1);
  lua_getfield(L, editor_state_index, "cx");
  int cx = lua_tointeger(L, -1);
  lua_settop(L, editor_state_index);
  int back_to_big_picture = edit_from(L, "teliva_editor_buffer", rowoff, coloff, cy, cx);
  // error handling
  int oldtop = lua_gettop(L);
  while (1) {
    int status;
    status = load_editor_buffer_to_current_definition_in_image(L);
    if (status == 0 || lua_isnil(L, -1))
      break;
    Previous_error = lua_tostring(L, -1);
    if (Previous_error == NULL) Previous_error = "(error object is not a string)";
    back_to_big_picture = resumeEdit(L);
    lua_pop(L, 1);
  }
  if (lua_gettop(L) != oldtop) {
    endwin();
    printf("edit_from: memory leak %d -> %d\n", oldtop, lua_gettop(L));
    exit(1);
  }
  return back_to_big_picture;
}

char** Argv = NULL;
extern void cleanup_curses(void);
void developer_mode(lua_State* L) {
  /* clobber the app's ncurses colors; we'll restart the app when we rerun it. */
  assume_default_colors(COLOR_FOREGROUND, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_NORMAL, COLOR_FOREGROUND, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_SELECTABLE, COLOR_SELECTABLE_FOREGROUND, COLOR_SELECTABLE_BACKGROUND);
  init_pair(COLOR_PAIR_FADE, COLOR_FADE, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_MENU_ALTERNATE, COLOR_MENU_ALTERNATE, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_LUA_COMMENT, COLOR_LUA_COMMENT, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_LUA_KEYWORD, COLOR_LUA_KEYWORD, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_LUA_CONSTANT, COLOR_LUA_CONSTANT, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_MATCH, COLOR_MATCH_FOREGROUND, COLOR_MATCH_BACKGROUND);
  init_pair(COLOR_PAIR_ERROR, COLOR_ERROR_FOREGROUND, COLOR_ERROR_BACKGROUND);
  nodelay(stdscr, 0);  /* always make getch() block in developer mode */
  curs_set(1);  /* always display cursor in developer mode */
  int switch_to_big_picture_view = 1;
  if (editor_view_in_progress(L))
    switch_to_big_picture_view = restore_editor_view(L);
  if (switch_to_big_picture_view)
    big_picture_view(L);
  cleanup_curses();
  execv(Argv[0], Argv);
  /* never returns */
}

char Current_definition[CURRENT_DEFINITION_LEN+1] = {0};

extern int mkstemp(char* template);
extern FILE* fdopen(int fd, const char* mode);
void save_editor_state(int rowoff, int coloff, int cy, int cx) {
  if (strlen(Current_definition) == 0) return;
  char outfilename[] = "teliva_editor_state_XXXXXX";
  int outfd = mkstemp(outfilename);
  if (outfd == -1) {
    endwin();
    perror("error in creating temporary file");
    abort();
  }
  FILE* out = fdopen(outfd, "w");
  assert(out != NULL);
  fprintf(out, "- image: %s\n", Image_name);
  fprintf(out, "  definition: %s\n", Current_definition);
  fprintf(out, "  rowoff: %d\n", rowoff);
  fprintf(out, "  coloff: %d\n", coloff);
  fprintf(out, "  cy: %d\n", cy);
  fprintf(out, "  cx: %d\n", cx);
  fclose(out);
  rename(outfilename, "teliva_editor_state");
}

/* when found, return 1 and leave string on top of stack
 * when not found, return 0
 * caller is responsible for cleaning up the stack. */
static int look_up_definition (lua_State* L, const char* name) {
  lua_getglobal(L, "teliva_program");
  int history_array = lua_gettop(L);
  /* iterate over mutations in teliva_program history in reverse order */
  int history_array_size = luaL_getn(L, history_array);
  for (int i = history_array_size; i > 0; --i) {
    lua_rawgeti(L, history_array, i);
    int table = lua_gettop(L);
    /* iterate over bindings */
    /* really we expect only one */
    for (lua_pushnil(L); lua_next(L, table) != 0; lua_pop(L, 1)) {
      const char* key = lua_tostring(L, -2);
      if (strcmp(key, "__teliva_undo") == 0) {
        int next_i = lua_tointeger(L, -1);
        assert(next_i < i);
        i = next_i + 1;  /* account for decrement */
        lua_pop(L, 1);
        break;
      }
      if (is_special_history_key(key)) continue;
      if (strcmp(key, name) == 0)
        return 1;
    }
    lua_pop(L, 1);
  }
  lua_pop(L, 1);
  return 0;
}

void save_to_current_definition_and_editor_buffer(lua_State* L, const char* definition) {
  int oldtop = lua_gettop(L);
  strncpy(Current_definition, definition, CURRENT_DEFINITION_LEN);
  int status = look_up_definition(L, Current_definition);
  char outfilename[] = "teliva_editor_buffer_XXXXXX";
  int outfd = mkstemp(outfilename);
  if (outfd == -1) {
    endwin();
    perror("save_to_current_definition_and_editor_buffer: error in creating temporary file");
    abort();
  }
  FILE* out = fdopen(outfd, "w");
  assert(out != NULL);
  if (status)
    fprintf(out, "%s", lua_tostring(L, -1));
  fclose(out);
  rename(outfilename, "teliva_editor_buffer");
  lua_settop(L, oldtop);
}

/* I don't understand the best way to read all of a text file.
 * I'm currently using fread, but its error handling is really designed for
 * binary data containing fixed-size records. */
static void read_editor_buffer(char* out, int capacity) {
  FILE* in = fopen("teliva_editor_buffer", "r");
  fread(out, capacity, 1, in);  /* TODO: handle overly large file */
  fclose(in);
}

static void update_definition(lua_State* L, const char* name, char* new_contents) {
  int oldtop = lua_gettop(L);
  lua_getglobal(L, "teliva_program");
  int history_array = lua_gettop(L);
  /* create a new table containing a single binding */
  lua_createtable(L, /*number of fields per mutation*/2, 0);
  lua_pushstring(L, new_contents);
  assert(strlen(name) > 0);
  lua_setfield(L, -2, name);
  /* include timestamp at which binding was created */
  time_t t;
  time(&t);
  char* time_string = ctime(&t);
  lua_pushstring(L, time_string);
  lua_setfield(L, -2, "__teliva_timestamp");
  /* append the new table to the history of mutations */
  int history_array_size = luaL_getn(L, history_array);
  ++history_array_size;
  lua_rawseti(L, history_array, history_array_size);
  lua_settop(L, oldtop);
}

extern void save_tlv(lua_State* L, char* filename);
extern int docall(lua_State* L, int narg, int clear);
extern int load_editor_buffer_to_current_definition_in_image(lua_State* L) {
  char new_contents[8192] = {0};
  read_editor_buffer(new_contents, 8190);
  update_definition(L, Current_definition, new_contents);
  save_tlv(L, Image_name);
  /* reload binding */
  return luaL_loadbuffer(L, new_contents, strlen(new_contents), Current_definition)
      || docall(L, 0, 1);
}

/* return true if user chose to back into the big picture view */
/* But only if there are no errors. Otherwise things can get confusing. */
extern int edit(lua_State* L, char* filename);
static int edit_current_definition(lua_State* L) {
  int back_to_big_picture = edit(L, "teliva_editor_buffer");
  // error handling
  int oldtop = lua_gettop(L);
  while (1) {
    int status;
    status = load_editor_buffer_to_current_definition_in_image(L);
    if (status == 0 || lua_isnil(L, -1))
      break;
    Previous_error = lua_tostring(L, -1);
    if (Previous_error == NULL) Previous_error = "(error object is not a string)";
    back_to_big_picture = resumeEdit(L);
    lua_pop(L, 1);
  }
  if (lua_gettop(L) != oldtop) {
    endwin();
    printf("edit_current_definition: memory leak %d -> %d\n", oldtop, lua_gettop(L));
    exit(1);
  }
  return back_to_big_picture;
}

static void recent_changes_menu(int cursor, int history_array_size) {
  attrset(A_REVERSE);
  for (int x = 0; x < COLS; ++x)
    mvaddch(LINES-1, x, ' ');
  attrset(A_NORMAL);
  menu_column = 2;
  draw_menu_item("^x", "go back");
  /* draw_menu_item("↓|space", "older"); */
  attroff(A_REVERSE);
  mvaddstr(LINES-1, menu_column, " ↓");
  attron(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("|");
  attroff(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("space ");
  menu_column += 9;  /* strlen isn't sufficient */
  attron(A_REVERSE);
  draw_string_on_menu("older");
  /* draw_menu_item("↑|backspace|delete|^h", "newer"); */
  attroff(A_REVERSE);
  mvaddstr(LINES-1, menu_column, " ↑");
  attron(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("|");
  attroff(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("backspace");
  attron(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("|");
  attroff(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("delete");
  attron(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("|");
  attroff(COLOR_PAIR(COLOR_PAIR_MENU_ALTERNATE));
  addstr("^h ");
  menu_column += 23;
  attron(A_REVERSE);
  draw_string_on_menu("newer");
  draw_menu_item("^e", "edit note");
  if (cursor < history_array_size)
    draw_menu_item("^u", "undo everything after this");
  attrset(A_NORMAL);
}

/* return final y containing text */
static int render_wrapped_lua_text(int y, int xmin, int xmax, const char* text) {
  int x = xmin;
  move(y, x);
  for (int j = 0; j < strlen(text); ++j) {
    char c = text[j];
    if (c == '-' && j+1 < strlen(text) && text[j+1] == '-')
      attron(COLOR_PAIR(COLOR_PAIR_LUA_COMMENT));
    if (c != '\n') {
      addch(text[j]);
      ++x;
      if (x >= xmax) {
        ++y;
        x = xmin;
        move(y, x);
      }
    }
    else {
      /* newline */
      ++y;
      x = xmin;
      move(y, x);
      attroff(COLOR_PAIR(COLOR_PAIR_LUA_COMMENT));
    }
  }
  return y;
}

static void render_recent_changes(lua_State* L, int start_index) {
  clear();
  attrset(A_BOLD);
  mvaddstr(1, 0, "Recent changes");
  attrset(A_NORMAL);
  int oldtop = lua_gettop(L);
  lua_getglobal(L, "teliva_program");
  int history_array = lua_gettop(L);
  int history_array_size = luaL_getn(L, history_array);
  int y = 3;
  attron(A_REVERSE);
  for (int i = start_index; i > 0; --i) {
    attron(A_BOLD);
    mvprintw(y, 0, "%3d. ", i);
    attrset(A_NORMAL);
    lua_rawgeti(L, history_array, i);
    int t = lua_gettop(L);
    for (lua_pushnil(L); lua_next(L, t) != 0; lua_pop(L, 1)) {
      if (strcmp(lua_tostring(L, -2), "__teliva_undo") == 0) {
        addstr("undo to ");
        attron(A_BOLD);
        printw("%d", lua_tointeger(L, -1));
        attroff(A_BOLD);
        y++;
        continue;
      }
      const char* definition_name = lua_tostring(L, -2);
      if (is_special_history_key(definition_name)) continue;
      addstr(definition_name);
      /* save timestamp of binding if available */
      lua_getfield(L, t, "__teliva_timestamp");
      if (!lua_isnil(L, -1)) {
        char buffer[128] = {0};
        strncpy(buffer, lua_tostring(L, -1), 120);
        if (buffer[strlen(buffer)-1] == '\n')
          buffer[strlen(buffer)-1] = '\0';
        attron(COLOR_PAIR(COLOR_PAIR_FADE));
        printw("  %s", buffer);
        attroff(COLOR_PAIR(COLOR_PAIR_FADE));
      }
      lua_pop(L, 1);
      lua_getfield(L, t, "__teliva_note");
      if (!lua_isnil(L, -1)) {
        attron(COLOR_PAIR(COLOR_PAIR_FADE));
        printw("  -- %s", lua_tostring(L, -1));
        attroff(COLOR_PAIR(COLOR_PAIR_FADE));
      }
      lua_pop(L, 1);
      y++;
      const char* definition_contents = lua_tostring(L, -1);
      y = render_wrapped_lua_text(y, 0, COLS, definition_contents);
      y++;
      if (y >= LINES-1) break;  /* leave cruft on the stack */
    }
    lua_settop(L, t);  /* clean up cruft on the stack */
    lua_pop(L, 1);  // history element
    y++;
    if (y >= LINES-1) break;
  }
  lua_pop(L, 1);  // history array
  if (lua_gettop(L) != oldtop) {
    endwin();
    printf("render_recent_changes: memory leak %d -> %d\n", oldtop, lua_gettop(L));
    exit(1);
  }
  recent_changes_menu(start_index, history_array_size);
  refresh();
}

static void add_undo_event(lua_State* L, int cursor) {
  lua_getglobal(L, "teliva_program");
  int history_array = lua_gettop(L);
  /* create a new table containing the undo event */
  lua_createtable(L, /*number of fields per mutation*/2, 0);
  lua_pushinteger(L, cursor);
  lua_setfield(L, -2, "__teliva_undo");
  /* include timestamp at which event was created */
  time_t t;
  time(&t);
  char* time_string = ctime(&t);
  lua_pushstring(L, time_string);
  lua_setfield(L, -2, "__teliva_timestamp");
  /* append the new table to the history of mutations */
  int history_array_size = luaL_getn(L, history_array);
  ++history_array_size;
  lua_rawseti(L, history_array, history_array_size);
  /* clean up */
  lua_pop(L, 1);
}

static void save_note_to_editor_buffer(lua_State* L, int cursor) {
  lua_getglobal(L, "teliva_program");
  lua_rawgeti(L, -1, cursor);
  lua_getfield(L, -1, "__teliva_note");
  const char* contents = lua_tostring(L, -1);
  char outfilename[] = "teliva_editor_buffer_XXXXXX";
  int outfd = mkstemp(outfilename);
  if (outfd == -1) {
    endwin();
    perror("save_note_to_editor_buffer: error in creating temporary file");
    abort();
  }
  FILE* out = fdopen(outfd, "w");
  assert(out != NULL);
  if (contents != NULL)
    fprintf(out, "%s", contents);
  fclose(out);
  rename(outfilename, "teliva_editor_buffer");
  lua_pop(L, 3);  /* contents, table at cursor, teliva_program */
}

static void load_note_from_editor_buffer(lua_State* L, int cursor) {
  lua_getglobal(L, "teliva_program");
  char new_contents[8192] = {0};
  read_editor_buffer(new_contents, 8190);
  lua_rawgeti(L, -1, cursor);
  lua_pushstring(L, new_contents);
  lua_setfield(L, -2, "__teliva_note");
  lua_pop(L, 2);  /* table at cursor, teliva_program */
}

static void recent_changes_view(lua_State* L) {
  lua_getglobal(L, "teliva_program");
  int history_array = lua_gettop(L);
  assert(history_array == 1);
  int history_array_size = luaL_getn(L, history_array);
  int cursor = history_array_size;
  lua_pop(L, 1);
  int quit = 0;
  while (!quit) {
    /* refresh state after each operation so we pick up modifications */
    render_recent_changes(L, cursor);
    int c = getch();
    switch (c) {
      case CTRL_X:
        quit = 1;
        break;
      case KEY_DOWN:
      case ' ':
        if (cursor > 1) --cursor;
        break;
      case KEY_UP:
      case KEY_BACKSPACE:
      case DELETE:
      case CTRL_H:
        if (cursor < history_array_size) ++cursor;
        break;
      case CTRL_E:
        save_note_to_editor_buffer(L, cursor);
        /* big picture hotkey unnecessarily available here */
        /* TODO: go hotkey is misleading. edits will not be persisted until you return to recent changes */
        edit(L, "teliva_editor_buffer");
        load_note_from_editor_buffer(L, cursor);
        save_tlv(L, Image_name);
        break;
      case CTRL_U:
        if (cursor < history_array_size) {
          add_undo_event(L, cursor);
          save_tlv(L, Image_name);
        }
        break;
    }
  }
}

static int binding_exists (lua_State *L, const char *name) {
  int result = 0;
  lua_getglobal(L, name);
  result = !lua_isnil(L, -1);
  lua_pop(L, 1);
  return result;
}

extern int dostring(lua_State* L, const char* s, const char* name);
static int load_definitions(lua_State* L) {
  int status;
  lua_getglobal(L, "teliva_program");
  int history_array = lua_gettop(L);
  /* iterate over mutations in teliva_program history in reverse order */
  int history_array_size = luaL_getn(L, history_array);
  for (int i = history_array_size; i > 0; --i) {
    lua_rawgeti(L, history_array, i);
    int table = lua_gettop(L);
    /* iterate over bindings */
    /* really we expect only one */
    for (lua_pushnil(L); lua_next(L, table) != 0; lua_pop(L, 1)) {
      const char* key = lua_tostring(L, -2);
      if (strcmp(key, "__teliva_undo") == 0) {
        int next_i = lua_tointeger(L, -1);
        assert(next_i < i);
        i = next_i + 1;  /* account for decrement */
        lua_pop(L, 1);
        break;
      }
      if (is_special_history_key(key)) continue;
      if (binding_exists(L, key))
        continue;  // most recent binding trumps older ones
      const char* value = lua_tostring(L, -1);
      status = dostring(L, value, key);
      if (status != 0) return report_in_developer_mode(L, status);
    }
    lua_pop(L, 1);
  }
  lua_pop(L, 1);
  return 0;
}

static int run_tests(lua_State* L) {
  clear();
  lua_pushinteger(L, 0);
  lua_setglobal(L, "teliva_num_test_failures");
  lua_pushnil(L);
  lua_setglobal(L, "teliva_first_failure");
  lua_pushvalue(L, LUA_GLOBALSINDEX);
  int table = lua_gettop(L);
  for (lua_pushnil(L); lua_next(L, table) != 0; lua_pop(L, 1)) {
    const char* key = lua_tostring(L, -2);
    if (strncmp("test_", key, strlen("test_")) != 0) continue;
    if (!lua_isfunction(L, -1)) continue;
    int status = lua_pcall(L, 0, 0, 0);
    if (status) {
      printw("E%d: %s", status, lua_tostring(L, -1));
      /* increment teliva_num_test_failures */
      lua_getglobal(L, "teliva_num_test_failures");
      int num_failures = lua_tointeger(L, -1);
      lua_pop(L, 1);
      lua_pushinteger(L, num_failures+1);
      lua_setglobal(L, "teliva_num_test_failures");
      /* if unset, set teliva_first_failure */
      lua_getglobal(L, "teliva_first_failure");
      int first_failure_clear = lua_isnil(L, -1);
      lua_pop(L, 1);
      if (first_failure_clear)
        lua_setglobal(L, "teliva_first_failure");
    }
    lua_pushnil(L);  /* just to undo loop update */
  }
  lua_pop(L, 1);
  lua_getglobal(L, "teliva_num_test_failures");
  int num_failures = lua_tointeger(L, -1);
  lua_pop(L, 1);
  if (num_failures == 0) return 0;
  if (num_failures == 1)
    addstr("1 failure");
  else
    printw("%d failures", num_failures);
  getch();
  /* take first failure back to developer mode */
  lua_getglobal(L, "teliva_first_failure");
  assert(!lua_isnil(L, -1));
  return 1;
}

static void clear_call_graph(lua_State* L) {
  int oldtop = lua_gettop(L);
  luaL_newmetatable(L, "__teliva_call_graph_depth");
  int cgt = lua_gettop(L);
  lua_pushnil(L);
  while (lua_next(L, cgt) != 0) {
    lua_pop(L, 1);  /* old value */
    lua_pushvalue(L, -1);  /* duplicate key */
    lua_pushnil(L);  /* new value */
    lua_settable(L, cgt);
    /* one copy of key left for lua_next */
  }
  lua_pop(L, 1);
  assert(lua_gettop(L) == oldtop);
}

int file_operations_allowed = false;
int net_operations_allowed = false;

static void permissions_menu() {
  attrset(A_REVERSE);
  for (int x = 0; x < COLS; ++x)
    mvaddch(LINES-1, x, ' ');
  attrset(A_NORMAL);
  menu_column = 2;
  draw_menu_item("^x", "go back");
  draw_menu_item("^f", "toggle file permissions");
  draw_menu_item("^n", "toggle network permissions");
  attrset(A_NORMAL);
}

static void render_permissions_screen(lua_State* L) {
  clear();
  attrset(A_BOLD);
  mvaddstr(1, 0, "Permissions");
  attrset(A_NORMAL);
  int file_colors = file_operations_allowed ? COLOR_PAIR_WARN : COLOR_PAIR_SAFE;
  int net_colors = net_operations_allowed ? COLOR_PAIR_WARN : COLOR_PAIR_SAFE;
  if (file_operations_allowed && net_operations_allowed) {
    file_colors = net_colors = COLOR_PAIR_RISK;
  }

  attron(COLOR_PAIR(file_colors));
  mvaddstr(3, 5, "File operations");
  attron(A_REVERSE);
  switch (file_colors) {
    case COLOR_PAIR_SAFE:
      mvaddstr(3, 30, " forbidden (safe)              ");
      break;
    case COLOR_PAIR_WARN:
      mvaddstr(3, 30, " allowed (more risky)          ");
      break;
    case COLOR_PAIR_RISK:
      mvaddstr(3, 30, "                               ");
      break;
    default:
      abort();
  }
  attroff(A_REVERSE);
  attroff(COLOR_PAIR(file_colors));

  attron(COLOR_PAIR(net_colors));
  mvaddstr(5, 5, "Network operations");
  attron(A_REVERSE);
  switch (net_colors) {
    case COLOR_PAIR_SAFE:
      mvaddstr(5, 30, " forbidden (safe)              ");
      break;
    case COLOR_PAIR_WARN:
      mvaddstr(5, 30, " allowed (more risky)          ");
      break;
    case COLOR_PAIR_RISK:
      mvaddstr(5, 30, "                               ");
      break;
    default:
      abort();
  }
  attroff(A_REVERSE);
  attroff(COLOR_PAIR(net_colors));

  if (file_operations_allowed && net_operations_allowed) {
    attron(COLOR_PAIR(COLOR_PAIR_RISK));
    mvaddstr(8, 5, "When both file and network operations are permitted, Teliva can't tell if this app does something sketchy.");
    mvaddstr(9, 5, "You're relying either on your understanding of its code, or your trust of its author(s).");
    attroff(COLOR_PAIR(COLOR_PAIR_RISK));
  }
  permissions_menu();
  refresh();
}

static void permissions_view(lua_State* L) {
  while (true) {
    render_permissions_screen(L);
    int c = getch();
    switch (c) {
      case CTRL_X:
        return;
      case CTRL_F:
        file_operations_allowed = !file_operations_allowed;
        break;
      case CTRL_N:
        net_operations_allowed = !net_operations_allowed;
        break;
    }
  }
}

static const char* user_configuration_filename() {
  const char* home = getenv("HOME");
  if (home == NULL) {
    endwin();
    fprintf(stderr, "$HOME is not set; unclear where to save permissions.\n");
    abort();
  }
  static char config_filename[1024] = {0};
  memset(config_filename, '\0', 1024);
  const char* config_home = getenv("XDG_CONFIG_HOME");
  if (config_home == NULL)
    snprintf(config_filename, 1024, "%s/.teliva", home);
  else
    snprintf(config_filename, 1024, "%s/.teliva", config_home);
  return config_filename;
}

static void save_permissions_to_user_configuration(lua_State* L) {
  const char* rcfilename = user_configuration_filename();
  FILE* in = fopen(rcfilename, "r");  /* can be NULL when rcfile doesn't exist */
  char outfilename[] = "telivarc_XXXXXX";
  int outfd = mkstemp(outfilename);
  if (outfd == -1) {
    endwin();
    perror("error in creating temporary file");
    abort();
  }
  FILE* out = fdopen(outfd, "w");
  assert(out != NULL);
  /* read entries from rcfilename and write them to outfilename. If image name
   * matches the current Image_name, ignore. */
  int oldtop = lua_gettop(L);
  while (in && !feof(in)) {
    teliva_load_definition(L, in);
    if (lua_isnil(L, -1)) break;
    lua_getfield(L, -1, "image_name");
    const char* image_name = lua_tostring(L, -1);
    if (strcmp(image_name, Image_name) != 0) {
      fprintf(out, "- image_name: %s\n", image_name);
      lua_getfield(L, -2, "file_operations_allowed");
      fprintf(out, "  file_operations_allowed: %s\n", lua_tostring(L, -1));
      lua_pop(L, 1);  /* file_operations_allowed */
      lua_getfield(L, -2, "net_operations_allowed");
      fprintf(out, "  net_operations_allowed: %s\n", lua_tostring(L, -1));
      lua_pop(L, 1);  /* net_operations_allowed */
    }
    lua_pop(L, 1);  /* image_name */
  }
  lua_settop(L, oldtop);
  fprintf(out, "- image_name: %s\n", Image_name);
  fprintf(out, "  file_operations_allowed: %d\n", file_operations_allowed);
  fprintf(out, "  net_operations_allowed: %d\n", net_operations_allowed);
  fclose(out);
  if (in) fclose(in);
  rename(outfilename, rcfilename);
}

static void load_permissions_from_user_configuration(lua_State* L) {
  const char* rcfilename = user_configuration_filename();
  FILE* in = fopen(rcfilename, "r");
  if (in == NULL) return;
  /* read entries from rcfilename and look for a match with the current
   * Image_name. */
  int oldtop = lua_gettop(L);
  while (!feof(in)) {
    teliva_load_definition(L, in);
    if (lua_isnil(L, -1)) break;
    lua_getfield(L, -1, "image_name");
    const char* image_name = lua_tostring(L, -1);
    if (strcmp(image_name, Image_name) == 0) {
      lua_getfield(L, -2, "file_operations_allowed");
      file_operations_allowed = lua_tointeger(L, -1);
      lua_pop(L, 1);  /* file_operations_allowed */
      lua_getfield(L, -2, "net_operations_allowed");
      net_operations_allowed = lua_tointeger(L, -1);
      lua_pop(L, 1);  /* net_operations_allowed */
    }
    lua_pop(L, 1);  /* image_name */
  }
  lua_settop(L, oldtop);
  fclose(in);
}

void permissions_mode(lua_State* L) {
  assume_default_colors(COLOR_FOREGROUND, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_NORMAL, COLOR_FOREGROUND, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_SELECTABLE, COLOR_SELECTABLE_FOREGROUND, COLOR_SELECTABLE_BACKGROUND);
  init_pair(COLOR_PAIR_FADE, COLOR_FADE, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_MENU_ALTERNATE, COLOR_MENU_ALTERNATE, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_LUA_COMMENT, COLOR_LUA_COMMENT, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_LUA_KEYWORD, COLOR_LUA_KEYWORD, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_LUA_CONSTANT, COLOR_LUA_CONSTANT, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_MATCH, COLOR_MATCH_FOREGROUND, COLOR_MATCH_BACKGROUND);
  init_pair(COLOR_PAIR_ERROR, COLOR_ERROR_FOREGROUND, COLOR_ERROR_BACKGROUND);
  /* permissions colors slightly different than in the menu */
  init_pair(COLOR_PAIR_SAFE, COLOR_SAFE_NORMAL, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_WARN, COLOR_WARN_NORMAL, COLOR_BACKGROUND);
  init_pair(COLOR_PAIR_RISK, COLOR_RISK_NORMAL, COLOR_BACKGROUND);
  nodelay(stdscr, 0);  /* always make getch() block in developer mode */
  curs_set(1);  /* always display cursor in developer mode */
  permissions_view(L);
  save_permissions_to_user_configuration(L);
  cleanup_curses();
  execv(Argv[0], Argv);
  /* never returns */
}

char* Image_name = NULL;
extern void set_args (lua_State *L, char **argv, int n);
extern void load_tlv(lua_State* L, char* filename);
int handle_image(lua_State* L, char** argv, int n) {
  int status;
  set_args(L, argv, n);
  /* parse and load file contents (teliva_program array) */
  Image_name = argv[n];
  load_tlv(L, Image_name);
//?   save_tlv(L, Image_name);  // manual test; should always return identical result, modulo key order
//?   exit(1);
  status = load_definitions(L);
  if (status != 0) return 0;
  status = run_tests(L);
  if (status != 0) return report_in_developer_mode(L, status);
  /* clear callgraph stats from running tests */
  clear_call_graph(L);
  /* initialize permissions */
  load_permissions_from_user_configuration(L);
  /* call main() */
  lua_getglobal(L, "main");
  status = docall(L, 0, 1);
  if (status != 0) return report_in_developer_mode(L, status);
  return 0;
}