1  /* SPDX-License-Identifier: LGPL-2.1-or-later */
       2  /*
       3   * This file is part of libmount from util-linux project.
       4   *
       5   * Copyright (C) 2008-2018 Karel Zak <kzak@redhat.com>
       6   *
       7   * libmount is free software; you can redistribute it and/or modify it
       8   * under the terms of the GNU Lesser General Public License as published by
       9   * the Free Software Foundation; either version 2.1 of the License, or
      10   * (at your option) any later version.
      11   */
      12  
      13  /**
      14   * SECTION: init
      15   * @title: Library initialization
      16   * @short_description: initialize debugging
      17   */
      18  
      19  #include <stdarg.h>
      20  
      21  #include "mountP.h"
      22  
      23  UL_DEBUG_DEFINE_MASK(libmount);
      24  UL_DEBUG_DEFINE_MASKNAMES(libmount) =
      25  {
      26  	{ "all", MNT_DEBUG_ALL,		"info about all subsystems" },
      27  	{ "cache", MNT_DEBUG_CACHE,	"paths and tags cache" },
      28  	{ "cxt", MNT_DEBUG_CXT,		"library context (handler)" },
      29  	{ "diff", MNT_DEBUG_DIFF,	"mountinfo changes tracking" },
      30  	{ "fs", MNT_DEBUG_FS,		"FS abstraction" },
      31  	{ "help", MNT_DEBUG_HELP,	"this help" },
      32  	{ "hook", MNT_DEBUG_HOOK,	"hooks functionality" },
      33  	{ "locks", MNT_DEBUG_LOCKS,	"mtab and utab locking" },
      34  	{ "loop", MNT_DEBUG_LOOP,	"loop devices routines" },
      35  	{ "options", MNT_DEBUG_OPTIONS,	"mount options parsing" },
      36  	{ "optlist", MNT_DEBUG_OPTLIST, "mount options container" },
      37  	{ "tab", MNT_DEBUG_TAB,		"fstab, mtab, mountinfo routines" },
      38  	{ "update", MNT_DEBUG_UPDATE,	"mtab, utab updates" },
      39  	{ "utils", MNT_DEBUG_UTILS,	"misc library utils" },
      40  	{ "monitor", MNT_DEBUG_MONITOR,	"mount tables monitor" },
      41  	{ "btrfs", MNT_DEBUG_BTRFS,	"btrfs specific routines" },
      42  	{ "verity", MNT_DEBUG_VERITY,	"verity specific routines" },
      43  
      44  	{ NULL, 0 }
      45  };
      46  
      47  /**
      48   * mnt_init_debug:
      49   * @mask: debug mask (0xffff to enable full debugging)
      50   *
      51   * If the @mask is not specified, then this function reads
      52   * the LIBMOUNT_DEBUG environment variable to get the mask.
      53   *
      54   * Already initialized debugging stuff cannot be changed. Calling
      55   * this function twice has no effect.
      56   */
      57  void mnt_init_debug(int mask)
      58  {
      59  	if (libmount_debug_mask)
      60  		return;
      61  
      62  	__UL_INIT_DEBUG_FROM_ENV(libmount, MNT_DEBUG_, mask, LIBMOUNT_DEBUG);
      63  
      64  	if (libmount_debug_mask != MNT_DEBUG_INIT
      65  	    && libmount_debug_mask != (MNT_DEBUG_HELP|MNT_DEBUG_INIT)) {
      66  		const char *ver = NULL;
      67  		const char **features = NULL, **p;
      68  
      69  		mnt_get_library_version(&ver);
      70  		mnt_get_library_features(&features);
      71  
      72  		DBG(INIT, ul_debug("library debug mask: 0x%06x", libmount_debug_mask));
      73  		DBG(INIT, ul_debug("library version: %s", ver));
      74  		p = features;
      75  		while (p && *p)
      76  			DBG(INIT, ul_debug("    feature: %s", *p++));
      77  	}
      78  
      79  	ON_DBG(HELP, ul_debug_print_masks("LIBMOUNT_DEBUG",
      80  				UL_DEBUG_MASKNAMES(libmount)));
      81  }
      82  
      83  #ifdef TEST_PROGRAM
      84  
      85  #include <errno.h>
      86  #include <stdlib.h>
      87  int main(int argc, char *argv[])
      88  {
      89  	if (argc == 2) {
      90  		int mask;
      91  
      92  		errno = 0;
      93  		mask = strtoul(argv[1], 0, 0);
      94  
      95  		if (errno)
      96  			return 1;
      97  
      98  		mnt_init_debug(mask);
      99  	}
     100  	else if (argc == 1) {
     101  		mnt_init_debug(0);
     102  	} else
     103  		return 1;
     104  
     105  	return 0;
     106  }
     107  #endif /* TEST_PROGRAM */
     108