cosmopolitan/libc/log/getsymboltable.c

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney                              │
│                                                                              │
│ This program is free software; you can redistribute it and/or modify         │
│ it under the terms of the GNU General Public License as published by         │
│ the Free Software Foundation; version 2 of the License.                      │
│                                                                              │
│ This program is distributed in the hope that it will be useful, but          │
│ WITHOUT ANY WARRANTY; without even the implied warranty of                   │
│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU             │
│ General Public License for more details.                                     │
│                                                                              │
│ You should have received a copy of the GNU General Public License            │
│ along with this program; if not, write to the Free Software                  │
│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA                │
│ 02110-1301 USA                                                               │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/runtime/symbols.h"

/**
 * Returns debug binary symbol table, as global singleton.
 * @return symbol table, or NULL w/ errno on first call
 */
struct SymbolTable *GetSymbolTable(void) {
  static bool once;
  static struct SymbolTable *singleton;
  const char *debugbin;
  if (!once) {
    once = true;
    if ((debugbin = FindDebugBinary()) &&
        (singleton = OpenSymbolTable(debugbin))) {
      __cxa_atexit(CloseSymbolTable, &singleton, NULL);
    }
  }
  return singleton;
}