path: root/src/nvim/highlight.c

// This is an open source non-commercial project. Dear PVS-Studio, please check
// it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com

// highlight.c: low level code for UI and syntax highlighting

#include <assert.h>
#include <inttypes.h>
#include <limits.h>
#include <string.h>

#include "klib/kvec.h"
#include "lauxlib.h"
#include "nvim/api/private/defs.h"
#include "nvim/api/private/helpers.h"
#include "nvim/api/ui.h"
#include "nvim/decoration_provider.h"
#include "nvim/drawscreen.h"
#include "nvim/gettext.h"
#include "nvim/globals.h"
#include "nvim/highlight.h"
#include "nvim/highlight_defs.h"
#include "nvim/highlight_group.h"
#include "nvim/log.h"
#include "nvim/lua/executor.h"
#include "nvim/macros.h"
#include "nvim/map.h"
#include "nvim/memory.h"
#include "nvim/message.h"
#include "nvim/option.h"
#include "nvim/popupmenu.h"
#include "nvim/types.h"
#include "nvim/ui.h"
#include "nvim/vim.h"

#ifdef INCLUDE_GENERATED_DECLARATIONS
# include "highlight.c.generated.h"
#endif

static bool hlstate_active = false;

static kvec_t(HlEntry) attr_entries = KV_INITIAL_VALUE;

static Map(HlEntry, int) attr_entry_ids = MAP_INIT;
static Map(int, int) combine_attr_entries = MAP_INIT;
static Map(int, int) blend_attr_entries = MAP_INIT;
static Map(int, int) blendthrough_attr_entries = MAP_INIT;

/// highlight entries private to a namespace
static Map(ColorKey, ColorItem) ns_hls;
typedef int NSHlAttr[HLF_COUNT + 1];
static PMap(handle_T) ns_hl_attr;

void highlight_init(void)
{
  // index 0 is no attribute, add dummy entry:
  kv_push(attr_entries, ((HlEntry){ .attr = HLATTRS_INIT, .kind = kHlUnknown,
                                    .id1 = 0, .id2 = 0 }));
}

/// @return true if hl table was reset
bool highlight_use_hlstate(void)
{
  if (hlstate_active) {
    return false;
  }
  hlstate_active = true;
  // hl tables must now be rebuilt.
  clear_hl_tables(true);
  return true;
}

/// Return the attr number for a set of colors and font, and optionally
/// a semantic description (see ext_hlstate documentation).
/// Add a new entry to the attr_entries array if the combination is new.
/// @return 0 for error.
static int get_attr_entry(HlEntry entry)
{
  if (!hlstate_active) {
    // This information will not be used, erase it and reduce the table size.
    entry.kind = kHlUnknown;
    entry.id1 = 0;
    entry.id2 = 0;
  }

  int id = map_get(HlEntry, int)(&attr_entry_ids, entry);
  if (id > 0) {
    return id;
  }

  static bool recursive = false;
  if (kv_size(attr_entries) > MAX_TYPENR) {
    // Running out of attribute entries!  remove all attributes, and
    // compute new ones for all groups.
    // When called recursively, we are really out of numbers.
    if (recursive) {
      emsg(_("E424: Too many different highlighting attributes in use"));
      return 0;
    }
    recursive = true;

    clear_hl_tables(true);

    recursive = false;
    if (entry.kind == kHlCombine) {
      // This entry is now invalid, don't put it
      return 0;
    }
  }

  size_t next_id = kv_size(attr_entries);
  if (next_id > INT_MAX) {
    ELOG("The index on attr_entries has overflowed");
    return 0;
  }
  id = (int)next_id;
  kv_push(attr_entries, entry);

  map_put(HlEntry, int)(&attr_entry_ids, entry, id);

  Array inspect = hl_inspect(id);

  // Note: internally we don't distinguish between cterm and rgb attributes,
  // remote_ui_hl_attr_define will however.
  ui_call_hl_attr_define(id, entry.attr, entry.attr, inspect);
  api_free_array(inspect);
  return id;
}

/// When a UI connects, we need to send it the table of highlights used so far.
void ui_send_all_hls(UI *ui)
{
  for (size_t i = 1; i < kv_size(attr_entries); i++) {
    Array inspect = hl_inspect((int)i);
    remote_ui_hl_attr_define(ui, (Integer)i, kv_A(attr_entries, i).attr,
                             kv_A(attr_entries, i).attr, inspect);
    api_free_array(inspect);
  }
  for (size_t hlf = 0; hlf < HLF_COUNT; hlf++) {
    remote_ui_hl_group_set(ui, cstr_as_string((char *)hlf_names[hlf]),
                           highlight_attr[hlf]);
  }
}

/// Get attribute code for a syntax group.
int hl_get_syn_attr(int ns_id, int idx, HlAttrs at_en)
{
  // TODO(bfredl): should we do this unconditionally
  if (at_en.cterm_fg_color != 0 || at_en.cterm_bg_color != 0
      || at_en.rgb_fg_color != -1 || at_en.rgb_bg_color != -1
      || at_en.rgb_sp_color != -1 || at_en.cterm_ae_attr != 0
      || at_en.rgb_ae_attr != 0 || ns_id != 0) {
    return get_attr_entry((HlEntry){ .attr = at_en, .kind = kHlSyntax,
                                     .id1 = idx, .id2 = ns_id });
  }
  // If all the fields are cleared, clear the attr field back to default value
  return 0;
}

void ns_hl_def(NS ns_id, int hl_id, HlAttrs attrs, int link_id, Dict(highlight) *dict)
{
  if (ns_id == 0) {
    assert(dict);
    // set in global (':highlight') namespace
    set_hl_group(hl_id, attrs, dict, link_id);
    return;
  }
  if ((attrs.rgb_ae_attr & HL_DEFAULT)
      && map_has(ColorKey, ColorItem)(&ns_hls, ColorKey(ns_id, hl_id))) {
    return;
  }
  DecorProvider *p = get_decor_provider(ns_id, true);
  int attr_id = link_id > 0 ? -1 : hl_get_syn_attr(ns_id, hl_id, attrs);
  ColorItem it = { .attr_id = attr_id,
                   .link_id = link_id,
                   .version = p->hl_valid,
                   .is_default = (attrs.rgb_ae_attr & HL_DEFAULT),
                   .link_global = (attrs.rgb_ae_attr & HL_GLOBAL) };
  map_put(ColorKey, ColorItem)(&ns_hls, ColorKey(ns_id, hl_id), it);
  p->hl_cached = false;
}

int ns_get_hl(NS *ns_hl, int hl_id, bool link, bool nodefault)
{
  static int recursive = 0;

  if (*ns_hl == 0) {
    // ns=0 (the default namespace) does not have a