kc3-lang/libxkbcommon/src/xkbcomp/keymap-dump.c

Branch : - branch - android master - tag -

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• Author : Pierre Le Marre
  Date : 2025-07-01 13:05:44
  Hash : e73d1a4d
  Message : Add support for all layout indices to GroupN constants This commit enables to use the pattern `Group<INDEX>` for any valid group index `<INDEX>`. Note that the original code in xkbcomp allows constants up to `Group8`, but then will fail if the resulting group is > 4. There does not seem to be any use case for this for such “feature”; it seems rather to be a relic from times were the 4-groups limit was not hopelessly fixed in X. So for consistency in our code base, starting with this commit we now disallow `Group5`..`Group8` for keymap format v1, since it is limited to 4 groups. Also fixed a regression in the serialization of group action, when the group is relative.

• src/xkbcomp/keymap-dump.c

• /*
   * For HPND:
   * Copyright (c) 1994 by Silicon Graphics Computer Systems, Inc.
   *
   * For MIT:
   * Copyright © 2012 Intel Corporation
   *
   * SPDX-License-Identifier: HPND AND MIT
   *
   * Author: Daniel Stone <daniel@fooishbar.org>
   */
  
  #include "config.h"
  
  #include <assert.h>
  #include <stdlib.h>
  
  #include "xkbcommon/xkbcommon.h"
  #include "keymap.h"
  #include "action.h"
  #include "messages-codes.h"
  #include "xkbcomp-priv.h"
  #include "text.h"
  
  #define BUF_CHUNK_SIZE 4096
  
  struct buf {
      char *buf;
      size_t size;
      size_t alloc;
  };
  
  #define xkb_abs(n) _Generic((n),                \
                              int: abs,           \
                              long int: labs,     \
                              default: llabs )((n))
  
  static bool
  do_realloc(struct buf *buf, size_t at_least)
  {
      buf->alloc += BUF_CHUNK_SIZE;
      if (at_least >= BUF_CHUNK_SIZE)
          buf->alloc += at_least;
  
      char *const new = realloc(buf->buf, buf->alloc);
      if (!new)
          return false;
  
      buf->buf = new;
      return true;
  }
  
  ATTR_PRINTF(2, 3) static bool
  check_write_buf(struct buf *buf, const char *fmt, ...)
  {
      va_list args;
      int printed;
      size_t available;
  
      available = buf->alloc - buf->size;
      /* Try to write to the buffer and get the required min size (without the
       * final null byte).
       * C11 states that if `available` is 0, then the pointer may be null. */
      assert(buf->buf || available == 0);
      va_start(args, fmt);
      printed = vsnprintf(buf->buf ? buf->buf + buf->size : buf->buf, available,
                          fmt, args);
      va_end(args);
  
      if (printed < 0) {
          /* Some error */
          goto err;
      } else if ((size_t) printed >= available) {
          /* Not enough space: need to realloc */
          if (!do_realloc(buf, printed + 1))
              goto err;
  
          /* The buffer has enough space now. */
          available = buf->alloc - buf->size;
          assert(buf->buf && (size_t) printed < available);
          va_start(args, fmt);
          printed = vsnprintf(buf->buf + buf->size, available, fmt, args);
          va_end(args);
  
          if (printed < 0 || (size_t) printed >= available)
              goto err;
      }
  
      buf->size += printed;
      return true;
  
  err:
      free(buf->buf);
      buf->buf = NULL;
      return false;
  }
  
  #define write_buf(buf, ...) do { \
      if (!check_write_buf(buf, __VA_ARGS__)) \
          return false; \
  } while (0)
  
  static bool
  check_copy_to_buf(struct buf *buf, const char* source, size_t len)
  {
      if (len == 0)
          return true;
  
      const size_t available = buf->alloc - buf->size;
      if (len >= available) {
          /* len + 1 (terminating NULL) */
          if (!do_realloc(buf, len + 1)) {
              free(buf->buf);
              buf->buf = NULL;
              return false;
          }
      }
  
      memcpy(buf->buf + buf->size, source, len);
      buf->size += len;
      /* Append NULL byte */
      buf->buf[buf->size] = '\0';
      return true;
  }
  
  #define copy_to_buf_len(buf, source, len) do { \
      if (!check_copy_to_buf(buf, source, len)) \
          return false; \
  } while (0)
  
  #define copy_to_buf(buf, source) \
      copy_to_buf_len(buf, source, sizeof(source) - 1)
  
  static bool
  check_write_string_literal(struct buf *buf, const char* string)
  {
      copy_to_buf(buf, "\"");
  
      /* Write chunks, separated by characters requiring escape sequence */
      size_t pending_start = 0;
      size_t current = 0;
      char escape_buffer[] = {'\\', '0', '0', '0', '0'};
      for (; string[current] != '\0'; current++) {
          uint8_t escape_len;
          switch (string[current]) {
          case '\n':
              /* `\n` would break strings */
              escape_buffer[1] = 'n';
              escape_len = 2;
              break;
          case '\\':
              /* `\` would create escape sequences */
              escape_buffer[1] = '\\';
              escape_len = 2;
              break;
          default:
              /*
               * Handle `"` (would break strings) and ASCII control characters
               * with an octal escape sequence. Xorg xkbcomp does not parse the
               * escape sequence `\"` nor xkbcommon < 1.9.0, so in order to be
               * backward compatible we must use the octal escape sequence in
               * xkbcomp style `\0nnn` with *4* digits:
               *
               * 1. To be compatible with Xorg xkbcomp.
               * 2. To avoid issues with the next char: e.g. "\00427" should not
               *    be emitted as "\427" nor "\0427".
               *
               * Note that xkbcommon < 1.9.0 will still not parse this correctly,
               * although it will not raise an error: e.g. the escape for `"`,
               * `\0042`, would be parsed as `\004` + `2`.
               */
              if (unlikely((unsigned char)string[current] < 0x20U ||
                           string[current] == '"')) {
                  escape_buffer[1] = '0';
                  escape_buffer[2] = '0';
                  escape_buffer[3] = (char)('0' + (string[current] >> 3));
                  escape_buffer[4] = (char)('0' + (string[current] & 0x7));
                  escape_len = 5;
              } else {
                  /* Expand the chunk */
                  continue;
              }
          }
          /* Write pending chunk */
          assert(current >= pending_start);
          copy_to_buf_len(buf, string + pending_start, current - pending_start);
          /* Write escape sequence */
          copy_to_buf_len(buf, escape_buffer, escape_len);
          pending_start = current + 1;
      }
      /* Write remaining chunk */
      assert(current >= pending_start);
      copy_to_buf_len(buf, string + pending_start, current - pending_start);
  
      copy_to_buf(buf, "\"");
      return true;
  }
  
  #define write_buf_string_literal(buf, string) do { \
      if (!check_write_string_literal(buf, string)) \
          return false; \
  } while (0)
  
  static bool
  write_vmods(struct xkb_keymap *keymap, enum xkb_keymap_format format,
              struct buf *buf)
  {
      const struct xkb_mod *mod;
      xkb_mod_index_t vmod = 0;
      bool has_some = false;
  
      xkb_vmods_enumerate(vmod, mod, &keymap->mods) {
          if (!has_some) {
              copy_to_buf(buf, "\tvirtual_modifiers ");
              has_some = true;
          } else {
              copy_to_buf(buf, ",");
          }
          write_buf(buf, "%s", xkb_atom_text(keymap->ctx, mod->name));
  
          /*
           * Ensure to always honor explicit mappings when auto canonical vmods
           * is enabled, so that parsing/serializing can round-trip. This is not
           * required when the feature is disabled (keymap format v1).
           *
           * If the auto feature is enabled, `virtual_modifiers M;` will assign
           * a canonical mapping > 0xff to `M` if there is no further explicit/
           * implicit mapping for `M`.
           *
           * On the contrary, `virtual_modifiers M = none;` prevents the auto
           * mapping of `M`. So if the auto feature is enabled and there is no
           * further explicit/implicit mapping for `M`, then the mapping of `M`
           * will remain unchanged: `none`. It must be serialized to an explicit
           * mapping to prevent triggering the auto canonical mapping presented
           * above.
           */
          const bool auto_canonical_mods = (format >= XKB_KEYMAP_FORMAT_TEXT_V2);
  
          if ((keymap->mods.explicit_vmods & (UINT32_C(1) << vmod)) &&
              (auto_canonical_mods || mod->mapping != 0)) {
              /*
               * Explicit non-default mapping
               * NOTE: we can only pretty-print *real* modifiers in this context.
               */
              write_buf(buf, "=%s",
                        ModMaskText(keymap->ctx, MOD_REAL, &keymap->mods,
                                    mod->mapping));
          }
      }
  
      if (has_some)
          copy_to_buf(buf, ";\n\n");
  
      return true;
  }
  
  static bool
  write_keycodes(struct xkb_keymap *keymap, struct buf *buf)
  {
      const struct xkb_key *key;
      xkb_led_index_t idx;
      const struct xkb_led *led;
  
      if (keymap->keycodes_section_name)
          write_buf(buf, "xkb_keycodes \"%s\" {\n",
                    keymap->keycodes_section_name);
      else
          copy_to_buf(buf, "xkb_keycodes {\n");
  
      /* xkbcomp and X11 really want to see keymaps with a minimum of 8, and
       * a maximum of at least 255, else XWayland really starts hating life.
       * If this is a problem and people really need strictly bounded keymaps,
       * we should probably control this with a flag. */
      write_buf(buf, "\tminimum = %"PRIu32";\n", MIN(keymap->min_key_code, 8));
      write_buf(buf, "\tmaximum = %"PRIu32";\n", MAX(keymap->max_key_code, 255));
  
      xkb_keys_foreach(key, keymap) {
          if (key->name == XKB_ATOM_NONE)
              continue;
  
          write_buf(buf, "\t%-20s = %"PRIu32";\n",
                    KeyNameText(keymap->ctx, key->name), key->keycode);
      }
  
      xkb_leds_enumerate(idx, led, keymap)
          if (led->name != XKB_ATOM_NONE) {
              write_buf(buf, "\tindicator %u = ", idx + 1);
              write_buf_string_literal(buf, xkb_atom_text(keymap->ctx, led->name));
              copy_to_buf(buf, ";\n");
          }
  
  
      for (darray_size_t i = 0; i < keymap->num_key_aliases; i++)
          write_buf(buf, "\talias %-14s = %s;\n",
                    KeyNameText(keymap->ctx, keymap->key_aliases[i].alias),
                    KeyNameText(keymap->ctx, keymap->key_aliases[i].real));
  
      copy_to_buf(buf, "};\n\n");
      return true;
  }
  
  static bool
  write_types(struct xkb_keymap *keymap, enum xkb_keymap_format format,
              struct buf *buf)
  {
      if (keymap->types_section_name)
          write_buf(buf, "xkb_types \"%s\" {\n",
                    keymap->types_section_name);
      else
          copy_to_buf(buf, "xkb_types {\n");
  
      if (!write_vmods(keymap, format, buf))
          return false;
  
      for (darray_size_t i = 0; i < keymap->num_types; i++) {
          const struct xkb_key_type *type = &keymap->types[i];
  
          copy_to_buf(buf, "\ttype ");
          write_buf_string_literal(buf, xkb_atom_text(keymap->ctx, type->name));
          copy_to_buf(buf, " {\n");
  
          write_buf(buf, "\t\tmodifiers= %s;\n",
                    ModMaskText(keymap->ctx, MOD_BOTH, &keymap->mods,
                                type->mods.mods));
  
          for (darray_size_t j = 0; j < type->num_entries; j++) {
              const char *str;
              const struct xkb_key_type_entry *entry = &type->entries[j];
  
              /*
               * Printing level 1 entries is redundant, it's the default,
               * unless there's preserve info.
               */
              if (entry->level == 0 && entry->preserve.mods == 0)
                  continue;
  
              str = ModMaskText(keymap->ctx, MOD_BOTH, &keymap->mods,
                                entry->mods.mods);
              write_buf(buf, "\t\tmap[%s]= %"PRIu32";\n",
                        str, entry->level + 1);
  
              if (entry->preserve.mods)
                  write_buf(buf, "\t\tpreserve[%s]= %s;\n",
                            str, ModMaskText(keymap->ctx, MOD_BOTH, &keymap->mods,
                                             entry->preserve.mods));
          }
  
          for (xkb_level_index_t n = 0; n < type->num_level_names; n++)
              if (type->level_names[n]) {
                  write_buf(buf, "\t\tlevel_name[%"PRIu32"]= ", n + 1);
                  write_buf_string_literal(
                      buf, xkb_atom_text(keymap->ctx, type->level_names[n]));
                  copy_to_buf(buf, ";\n");
              }
  
  
          copy_to_buf(buf, "\t};\n");
      }
  
      copy_to_buf(buf, "};\n\n");
      return true;
  }
  
  static bool
  write_led_map(struct xkb_keymap *keymap, struct buf *buf,
                const struct xkb_led *led)
  {
      copy_to_buf(buf, "\tindicator ");
      write_buf_string_literal(buf, xkb_atom_text(keymap->ctx, led->name));
      copy_to_buf(buf, " {\n");
  
      if (led->which_groups) {
          if (led->which_groups != XKB_STATE_LAYOUT_EFFECTIVE) {
              write_buf(buf, "\t\twhichGroupState= %s;\n",
                        LedStateMaskText(keymap->ctx, groupComponentMaskNames,
                                         led->which_groups));
          }
          write_buf(buf, "\t\tgroups= 0x%02x;\n",
                    led->groups);
      }
  
      if (led->which_mods) {
          if (led->which_mods != XKB_STATE_MODS_EFFECTIVE) {
              write_buf(buf, "\t\twhichModState= %s;\n",
                        LedStateMaskText(keymap->ctx, modComponentMaskNames,
                                         led->which_mods));
          }
          write_buf(buf, "\t\tmodifiers= %s;\n",
                    ModMaskText(keymap->ctx, MOD_BOTH, &keymap->mods,
                                led->mods.mods));
      }
  
      if (led->ctrls) {
          write_buf(buf, "\t\tcontrols= %s;\n",
                    ControlMaskText(keymap->ctx, led->ctrls));
      }
  
      copy_to_buf(buf, "\t};\n");
      return true;
  }
  
  static const char *
  affect_lock_text(enum xkb_action_flags flags, bool show_both)
  {
      switch (flags & (ACTION_LOCK_NO_LOCK | ACTION_LOCK_NO_UNLOCK)) {
      case 0:
          return show_both ? ",affect=both" : "";
      case ACTION_LOCK_NO_UNLOCK:
          return ",affect=lock";
      case ACTION_LOCK_NO_LOCK:
          return ",affect=unlock";
      case ACTION_LOCK_NO_LOCK | ACTION_LOCK_NO_UNLOCK:
          return ",affect=neither";
      default:
          return "";
      }
  }
  
  #define SYMBOL_PADDING 15
  #define ACTION_PADDING 30
  
  static bool
  write_action(struct xkb_keymap *keymap, enum xkb_keymap_format format,
               xkb_layout_index_t max_groups, struct buf *buf,
               const union xkb_action *action,
               const char *prefix, const char *suffix)
  {
      const char *type;
      const char *args = NULL;
  
      if (!prefix)
          prefix = "";
      if (!suffix)
          suffix = "";
  
      type = ActionTypeText(action->type);
  
      switch (action->type) {
      case ACTION_TYPE_MOD_SET:
      case ACTION_TYPE_MOD_LATCH:
      case ACTION_TYPE_MOD_LOCK:
          if (action->mods.flags & ACTION_MODS_LOOKUP_MODMAP)
              args = "modMapMods";
          else
              args = ModMaskText(keymap->ctx, MOD_BOTH, &keymap->mods,
                                 action->mods.mods.mods);
          bool unlockOnPress = (action->mods.flags & ACTION_UNLOCK_ON_PRESS);
          if (unlockOnPress && !isModsUnLockOnPressSupported(format)) {
              log_err(keymap->ctx, XKB_ERROR_INCOMPATIBLE_KEYMAP_TEXT_FORMAT,
                      "Cannot use \"%s(unlockOnPress=true)\" in keymap format %d\n",
                      ActionTypeText(action->type), format);
              unlockOnPress = false;
          }
          bool latchOnPress = action->type == ACTION_TYPE_MOD_LATCH &&
                              (action->group.flags & ACTION_LATCH_ON_PRESS);
          if (latchOnPress && !isModsLatchOnPressSupported(format)) {
              log_err(keymap->ctx, XKB_ERROR_INCOMPATIBLE_KEYMAP_TEXT_FORMAT,
                      "Cannot use \"LatchMods(latchOnPress=true)\" "
                      "in keymap format %d\n", format);
              latchOnPress = false;
          }
          write_buf(buf, "%s%s(modifiers=%s%s%s%s%s%s)%s", prefix, type, args,
                    (action->type != ACTION_TYPE_MOD_LOCK && (action->mods.flags & ACTION_LOCK_CLEAR)) ? ",clearLocks" : "",
                    (action->type != ACTION_TYPE_MOD_LOCK && (action->mods.flags & ACTION_LATCH_TO_LOCK)) ? ",latchToLock" : "",
                    (action->type == ACTION_TYPE_MOD_LOCK) ? affect_lock_text(action->mods.flags, false) : "",
                    (unlockOnPress) ? ",unlockOnPress" : "",
                    (latchOnPress) ? ",latchOnPress" : "",
                    suffix);
          break;
  
      case ACTION_TYPE_GROUP_SET:
      case ACTION_TYPE_GROUP_LATCH:
      case ACTION_TYPE_GROUP_LOCK:
          if ((uint32_t) xkb_abs(action->group.group) <
              (max_groups + !(action->group.flags & ACTION_ABSOLUTE_SWITCH))) {
              bool lockOnRelease = action->type == ACTION_TYPE_GROUP_LOCK &&
                                   (action->group.flags & ACTION_LOCK_ON_RELEASE);
              if (lockOnRelease && !isGroupLockOnReleaseSupported(format)) {
                  log_err(keymap->ctx, XKB_ERROR_INCOMPATIBLE_KEYMAP_TEXT_FORMAT,
                          "Cannot use \"GroupLock(lockOnRelease=true)\" "
                          "in keymap format %d\n", format);
                  lockOnRelease = false;
              }
              write_buf(buf, "%s%s(group=%s%"PRId32"%s%s%s)%s", prefix, type,
                        (!(action->group.flags & ACTION_ABSOLUTE_SWITCH) && action->group.group > 0) ? "+" : "",
                        (action->group.flags & ACTION_ABSOLUTE_SWITCH) ? action->group.group + 1 : action->group.group,
                        (action->type != ACTION_TYPE_GROUP_LOCK && (action->group.flags & ACTION_LOCK_CLEAR)) ? ",clearLocks" : "",
                        (action->type != ACTION_TYPE_GROUP_LOCK && (action->group.flags & ACTION_LATCH_TO_LOCK)) ? ",latchToLock" : "",
                        (lockOnRelease) ? ",lockOnRelease" : "",
                        suffix);
          } else {
              /* Unsupported group index: degrade to VoidAction() */
              goto void_action;
          }
          break;
  
      case ACTION_TYPE_TERMINATE:
          write_buf(buf, "%s%s()%s", prefix, type, suffix);
          break;
  
      case ACTION_TYPE_PTR_MOVE:
          write_buf(buf, "%s%s(x=%s%d,y=%s%d%s)%s", prefix, type,
                    (!(action->ptr.flags & ACTION_ABSOLUTE_X) && action->ptr.x >= 0) ? "+" : "",
                    action->ptr.x,
                    (!(action->ptr.flags & ACTION_ABSOLUTE_Y) && action->ptr.y >= 0) ? "+" : "",
                    action->ptr.y,
                    (action->ptr.flags & ACTION_ACCEL) ? "" : ",!accel",
                    suffix);
          break;
  
      case ACTION_TYPE_PTR_LOCK:
          args = affect_lock_text(action->btn.flags, true);
          /* fallthrough */
      case ACTION_TYPE_PTR_BUTTON:
          write_buf(buf, "%s%s(button=", prefix, type);
          if (action->btn.button > 0 && action->btn.button <= 5)
              write_buf(buf, "%u", action->btn.button);
          else
              copy_to_buf(buf, "default");
          if (action->btn.count)
              write_buf(buf, ",count=%u", action->btn.count);
          if (args)
              write_buf(buf, "%s", args);
          write_buf(buf, ")%s", suffix);
          break;
  
      case ACTION_TYPE_PTR_DEFAULT:
          write_buf(buf, "%s%s(", prefix, type);
          write_buf(buf, "affect=button,button=%s%d",
                    (!(action->dflt.flags & ACTION_ABSOLUTE_SWITCH) && action->dflt.value >= 0) ? "+" : "",
                    action->dflt.value);
          write_buf(buf, ")%s", suffix);
          break;
  
      case ACTION_TYPE_SWITCH_VT:
          write_buf(buf, "%s%s(screen=%s%d,%ssame)%s", prefix, type,
                    (!(action->screen.flags & ACTION_ABSOLUTE_SWITCH) && action->screen.screen >= 0) ? "+" : "",
                    action->screen.screen,
                    (action->screen.flags & ACTION_SAME_SCREEN) ? "" : "!",
                    suffix);
          break;
  
      case ACTION_TYPE_CTRL_SET:
      case ACTION_TYPE_CTRL_LOCK:
          write_buf(buf, "%s%s(controls=%s%s)%s", prefix, type,
                    ControlMaskText(keymap->ctx, action->ctrls.ctrls),
                    (action->type == ACTION_TYPE_CTRL_LOCK) ? affect_lock_text(action->ctrls.flags, false) : "",
                    suffix);
          break;
  
      case ACTION_TYPE_NONE:
          write_buf(buf, "%sNoAction()%s", prefix, suffix);
          break;
  
      case ACTION_TYPE_VOID:
  void_action:
          /*
           * VoidAction() is a libxkbcommon extension.
           * Use LockControls as a backward-compatible fallback.
           * We cannot serialize it to `NoAction()`, as it would be dropped in
           * e.g. the context of multiple actions.
           * We better not use `Private` either, because it could still be
           * interpreted by X11.
           */
          if (format == XKB_KEYMAP_FORMAT_TEXT_V1)
              write_buf(buf, "%sLockControls(controls=none,affect=neither)%s",
                        prefix, suffix);
          else
              write_buf(buf, "%sVoidAction()%s", prefix, suffix);
          break;
  
      default:
          /* Unsupported legacy actions should have degraded to NoAction */
          assert(action->type != ACTION_TYPE_UNSUPPORTED_LEGACY);
          write_buf(buf,
                    "%s%s(type=0x%02x,data[0]=0x%02x,data[1]=0x%02x,data[2]=0x%02x,data[3]=0x%02x,data[4]=0x%02x,data[5]=0x%02x,data[6]=0x%02x)%s",
                    prefix, type, action->type, action->priv.data[0],
                    action->priv.data[1], action->priv.data[2],
                    action->priv.data[3], action->priv.data[4],
                    action->priv.data[5], action->priv.data[6],
                    suffix);
          break;
      }
  
      return true;
  }
  
  static const union xkb_action void_actions[] = {
      { .type = ACTION_TYPE_VOID }
  };
  
  static bool
  write_actions(struct xkb_keymap *keymap, enum xkb_keymap_format format,
                xkb_layout_index_t max_groups, struct buf *buf, struct buf *buf2,
                const struct xkb_key *key, xkb_layout_index_t group)
  {
      static const union xkb_action noAction = { .type = ACTION_TYPE_NONE };
  
      for (xkb_level_index_t level = 0; level < XkbKeyNumLevels(key, group);
           level++) {
  
          if (level != 0)
              copy_to_buf(buf, ", ");
  
          const union xkb_action *actions = NULL;
          xkb_action_count_t count = xkb_keymap_key_get_actions_by_level(
              keymap, key, group, level, &actions
          );
  
          if (count > 1 && format < XKB_KEYMAP_FORMAT_TEXT_V2) {
              /* V1: Degrade multiple actions to VoidAction() */
              actions = void_actions;
              count = 1;
              log_err(keymap->ctx, XKB_ERROR_INCOMPATIBLE_KEYMAP_TEXT_FORMAT,
                      "Cannot serialize multiple actions per level "
                      "in keymap format %d; degrade to VoidAction()\n", format);
          }
  
          buf2->size = 0;
          if (count == 0) {
              if (!write_action(keymap, format, max_groups,
                                buf2, &noAction, NULL, NULL))
                  return false;
              write_buf(buf, "%*s", ACTION_PADDING, buf2->buf);
          }
          else if (count == 1) {
              if (!write_action(keymap, format, max_groups,
                                buf2, &(actions[0]), NULL, NULL))
                  return false;
              write_buf(buf, "%*s", ACTION_PADDING, buf2->buf);
          }
          else {
              copy_to_buf(buf2, "{ ");
              for (xkb_action_count_t k = 0; k < count; k++) {
                  if (k != 0)
                      copy_to_buf(buf2, ", ");
                  size_t old_size = buf2->size;
                  if (!write_action(keymap, format, max_groups,
                                    buf2, &(actions[k]), NULL, NULL))
                      return false;
                  /* Check if padding is necessary */
                  if (buf2->size >= old_size + ACTION_PADDING)
                      continue;
                  /* Compute and write padding, then write the action again */
                  const int padding = (int)(old_size + ACTION_PADDING - buf2->size);
                  buf2->size = old_size;
                  write_buf(buf2, "%*s", padding, "");
                  if (!write_action(keymap, format, max_groups,
                                    buf2, &(actions[k]), NULL, NULL))
                      return false;
              }
              copy_to_buf(buf2, " }");
              write_buf(buf, "%*s", ACTION_PADDING, buf2->buf);
          }
      }
  
      return true;
  }
  
  static bool
  write_compat(struct xkb_keymap *keymap, enum xkb_keymap_format format,
               xkb_layout_index_t max_groups, struct buf *buf)
  {
      const struct xkb_led *led;
  
      if (keymap->compat_section_name)
          write_buf(buf, "xkb_compatibility \"%s\" {\n",
                    keymap->compat_section_name);
      else
          copy_to_buf(buf, "xkb_compatibility {\n");
  
      if (!write_vmods(keymap, format, buf))
          return false;
  
      copy_to_buf(buf, "\tinterpret.useModMapMods= AnyLevel;\n");
      copy_to_buf(buf, "\tinterpret.repeat= False;\n");
  
      /* xkbcomp requires at least one interpret entry. */
      const darray_size_t num_sym_interprets = keymap->num_sym_interprets
                                             ? keymap->num_sym_interprets
                                             : 1;
      const struct xkb_sym_interpret* const sym_interprets
          = keymap->num_sym_interprets
          ? keymap->sym_interprets
          : &default_interpret;
  
      for (darray_size_t i = 0; i < num_sym_interprets; i++) {
          const struct xkb_sym_interpret *si = &sym_interprets[i];
  
          write_buf(buf, "\tinterpret %s+%s(%s) {",
                    si->sym ? KeysymText(keymap->ctx, si->sym) : "Any",
                    SIMatchText(si->match),
                    ModMaskText(keymap->ctx, MOD_BOTH, &keymap->mods, si->mods));
  
          bool has_explicit_properties = false;
  
          if (si->virtual_mod != XKB_MOD_INVALID) {
              write_buf(buf, "\n\t\tvirtualModifier= %s;",
                        ModIndexText(keymap->ctx, &keymap->mods,
                                     si->virtual_mod));
              has_explicit_properties = true;
          }
  
          if (si->level_one_only) {
              copy_to_buf(buf, "\n\t\tuseModMapMods=level1;");
              has_explicit_properties = true;
          }
  
          if (si->repeat) {
              copy_to_buf(buf, "\n\t\trepeat= True;");
              has_explicit_properties = true;
          }
  
          const union xkb_action *action = NULL;
          xkb_action_count_t action_count = si->num_actions;
          if (action_count <= 1) {
              action = &si->a.action;
          }
          else if (format < XKB_KEYMAP_FORMAT_TEXT_V2) {
              /* V1: Degrade multiple actions to VoidAction() */
              action = &void_actions[0];
              action_count = 1;
              log_err(keymap->ctx, XKB_ERROR_INCOMPATIBLE_KEYMAP_TEXT_FORMAT,
                      "Cannot serialize multiple actions per level "
                      "in keymap format %d; degrade to VoidAction()\n", format);
          }
  
          if (action_count > 1) {
              copy_to_buf(buf, "\n\t\taction= {");
              const char suffix[] = ", ";
              for (xkb_action_count_t k = 0; k < si->num_actions; k++) {
                  if (!write_action(keymap, format, max_groups,
                                    buf, &si->a.actions[k], "", suffix))
                      return false;
              }
              buf->size -= sizeof(suffix) - 1; /* trailing comma */
              copy_to_buf(buf, "};");
              has_explicit_properties = true;
          } else if (action_count == 1) {
              if (!write_action(keymap, format, max_groups, buf, action,
                                "\n\t\taction= ", ";"))
                  return false;
              has_explicit_properties = true;
          }
          write_buf(buf, (has_explicit_properties
                          ? "\n\t};\n"
                          /* Empty interpret is a syntax error in xkbcomp, so
                           * use a dummy entry */
                          : "\n\t\taction= NoAction();\n\t};\n"));
      }
  
      xkb_leds_foreach(led, keymap)
          if (led->which_groups || led->groups || led->which_mods ||
              led->mods.mods || led->ctrls)
              if (!write_led_map(keymap, buf, led))
                  return false;
  
      copy_to_buf(buf, "};\n\n");
  
      return true;
  }
  
  static bool
  write_keysyms(struct xkb_keymap *keymap, struct buf *buf, struct buf *buf2,
                const struct xkb_key *key, xkb_layout_index_t group,
                bool show_actions)
  {
      unsigned int padding = show_actions ? ACTION_PADDING : SYMBOL_PADDING;
      for (xkb_level_index_t level = 0; level < XkbKeyNumLevels(key, group);
           level++) {
          const xkb_keysym_t *syms;
          int num_syms;
  
          if (level != 0)
              copy_to_buf(buf, ", ");
  
          num_syms = xkb_keymap_key_get_syms_by_level(keymap, key->keycode,
                                                      group, level, &syms);
          if (num_syms == 0) {
              write_buf(buf, "%*s", padding, "NoSymbol");
          }
          else if (num_syms == 1) {
              write_buf(buf, "%*s", padding, KeysymText(keymap->ctx, syms[0]));
          }
          else {
              buf2->size = 0;
              copy_to_buf(buf2, "{ ");
              for (int s = 0; s < num_syms; s++) {
                  if (s != 0)
                      copy_to_buf(buf2, ", ");
                  write_buf(buf2, "%*s", (show_actions ? padding : 0),
                            KeysymText(keymap->ctx, syms[s]));
              }
              copy_to_buf(buf2, " }");
              write_buf(buf, "%*s", padding, buf2->buf);
          }
      }
  
      return true;
  }
  
  static bool
  write_key(struct xkb_keymap *keymap, enum xkb_keymap_format format,
            xkb_layout_index_t max_groups,
            struct buf *buf, struct buf *buf2, const struct xkb_key *key)
  {
      bool simple = true;
      const xkb_layout_index_t num_groups = MIN(key->num_groups, max_groups);
  
      write_buf(buf, "\tkey %-20s {", KeyNameText(keymap->ctx, key->name));
  
      if (key->explicit & EXPLICIT_TYPES) {
          simple = false;
  
          bool multi_type = false;
          for (xkb_layout_index_t group = 1; group < num_groups; group++) {
              if (key->groups[group].type != key->groups[0].type) {
                  multi_type = true;
                  break;
              }
          }
  
          if (multi_type) {
              for (xkb_layout_index_t group = 0; group < num_groups; group++) {
                  if (!key->groups[group].explicit_type)
                      continue;
  
                  const struct xkb_key_type * const type = key->groups[group].type;
                  write_buf(buf, "\n\t\ttype[%"PRIu32"]= ", group + 1);
                  write_buf_string_literal(
                    buf, xkb_atom_text(keymap->ctx, type->name));
                  copy_to_buf(buf, ",");
              }
          }
          else {
              const struct xkb_key_type * const type = key->groups[0].type;
              write_buf(buf, "\n\t\ttype= ");
              write_buf_string_literal(
                  buf, xkb_atom_text(keymap->ctx, type->name));
              copy_to_buf(buf, ",");
          }
      }
  
      /*
       * NOTE: we use key->explicit and not key->group[i].explicit_actions, in
       * order to have X11 and the previous versions of libxkbcommon (without this
       * group property) parse the keymap as intended, by setting explicitly for
       * this key all actions in all groups.
       *
       * One side effect is that no interpretation will be run on this key anymore,
       * so we may have to set some extra fields explicitly: repeat, virtualMods.
       */
      const bool show_actions = (key->explicit & EXPLICIT_INTERP);
  
      /* If we show actions, interprets are not going to be used to set this
       * field, so make it explicit. */
      if ((key->explicit & EXPLICIT_REPEAT) || show_actions) {
          if (key->repeats)
              copy_to_buf(buf, "\n\t\trepeat= Yes,");
          else
              copy_to_buf(buf, "\n\t\trepeat= No,");
      }
  
      /* If we show actions, interprets are not going to be used to set this
       * field, so make it explicit. */
      if ((key->explicit & EXPLICIT_VMODMAP) || (show_actions && key->vmodmap))
          write_buf(buf, "\n\t\tvirtualMods= %s,",
                    ModMaskText(keymap->ctx, MOD_BOTH, &keymap->mods,
                                key->vmodmap));
  
      switch (key->out_of_range_group_action) {
      case RANGE_SATURATE:
          copy_to_buf(buf, "\n\t\tgroupsClamp,");
          break;
  
      case RANGE_REDIRECT:
          if (key->out_of_range_group_number < num_groups) {
              /* TODO: Fallback or warning if condition fails? */
              write_buf(buf, "\n\t\tgroupsRedirect= %"PRIu32",",
                        key->out_of_range_group_number + 1);
          }
          break;
  
      default:
          break;
      }
  
      if (num_groups > 1 || show_actions)
          simple = false;
  
      if (simple) {
          const bool only_symbols = key->explicit == EXPLICIT_SYMBOLS;
          if (num_groups == 0) {
              /* Remove trailing comma */
              if (buf->buf[buf->size - 1] == ',')
                  buf->size--;
          } else {
  	        if (!only_symbols)
  	            copy_to_buf(buf, "\n\t");
              copy_to_buf(buf, "\t[ ");
              if (!write_keysyms(keymap, buf, buf2, key, 0, false))
                  return false;
              copy_to_buf(buf, " ]");
          }
          write_buf(buf, "%s", (only_symbols ? " };\n" : "\n\t};\n"));
      }
      else {
          assert(num_groups > 0);
          for (xkb_layout_index_t group = 0; group < num_groups; group++) {
              if (group != 0)
                  copy_to_buf(buf, ",");
              write_buf(buf, "\n\t\tsymbols[%"PRIu32"]= [ ", group + 1);
              if (!write_keysyms(keymap, buf, buf2, key, group, show_actions))
                  return false;
              copy_to_buf(buf, " ]");
              if (show_actions) {
                  write_buf(buf, ",\n\t\tactions[%"PRIu32"]= [ ", group + 1);
                  if (!write_actions(keymap, format, max_groups,
                                     buf, buf2, key, group))
                      return false;
                  copy_to_buf(buf, " ]");
              }
          }
          copy_to_buf(buf, "\n\t};\n");
      }
  
      return true;
  }
  
  static bool
  write_symbols(struct xkb_keymap *keymap, enum xkb_keymap_format format,
                xkb_layout_index_t max_groups, struct buf *buf)
  {
  
      if (keymap->symbols_section_name)
          write_buf(buf, "xkb_symbols \"%s\" {\n", keymap->symbols_section_name);
      else
          copy_to_buf(buf, "xkb_symbols {\n");
  
      const xkb_layout_index_t num_group_names = MIN(keymap->num_group_names,
                                                     max_groups);
      bool has_group_names = false;
      for (xkb_layout_index_t group = 0; group < num_group_names; group++)
          if (keymap->group_names[group]) {
              write_buf(buf, "\tname[%"PRIu32"]=", group + 1);
              write_buf_string_literal(
                  buf, xkb_atom_text(keymap->ctx, keymap->group_names[group]));
              copy_to_buf(buf, ";\n");
              has_group_names = true;
          }
      if (has_group_names)
          copy_to_buf(buf, "\n");
  
      struct buf buf2 = { NULL, 0, 0 };
      const struct xkb_key *key;
      xkb_keys_foreach(key, keymap) {
          /* Skip keys with no explicit values */
          if (key->explicit) {
              if (!write_key(keymap, format, max_groups, buf, &buf2, key)) {
                  free(buf2.buf);
                  return false;
              }
          }
      }
      free(buf2.buf);
  
      xkb_mod_index_t i;
      const struct xkb_mod *mod;
      xkb_rmods_enumerate(i, mod, &keymap->mods) {
          bool had_any = false;
          xkb_keys_foreach(key, keymap) {
              if (key->modmap & (UINT32_C(1) << i)) {
                  if (!had_any)
                      write_buf(buf, "\tmodifier_map %s { ",
                                xkb_atom_text(keymap->ctx, mod->name));
                  write_buf(buf, "%s%s",
                            had_any ? ", " : "",
                            KeyNameText(keymap->ctx, key->name));
                  had_any = true;
              }
          }
          if (had_any)
              copy_to_buf(buf, " };\n");
      }
  
      copy_to_buf(buf, "};\n\n");
      return true;
  }
  
  static bool
  write_keymap(struct xkb_keymap *keymap, enum xkb_keymap_format format,
               struct buf *buf)
  {
      const xkb_layout_index_t max_groups = format_max_groups(format);
      if (keymap->num_groups > max_groups) {
          log_err(keymap->ctx, XKB_ERROR_UNSUPPORTED_GROUP_INDEX,
                  "Cannot serialize %"PRIu32" groups in keymap format %d: "
                  "maximum is %"PRIu32"; discarding unsupported groups\n",
                  keymap->num_groups, format, max_groups);
      }
  
      return (check_write_buf(buf, "xkb_keymap {\n") &&
              write_keycodes(keymap, buf) &&
              write_types(keymap, format, buf) &&
              write_compat(keymap, format, max_groups, buf) &&
              write_symbols(keymap, format, max_groups, buf) &&
              check_write_buf(buf, "};\n"));
  }
  
  char *
  text_v1_keymap_get_as_string(struct xkb_keymap *keymap,
                               enum xkb_keymap_format format)
  {
      struct buf buf = { NULL, 0, 0 };
  
      if (!write_keymap(keymap, format, &buf)) {
          free(buf.buf);
          return NULL;
      }
  
      return buf.buf;
  }