src/shared/conf-parser.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2010 Lennart Poettering
   8
   9   systemd is free software; you can redistribute it and/or modify it
  10   under the terms of the GNU Lesser General Public License as published by
  11   the Free Software Foundation; either version 2.1 of the License, or
  12   (at your option) any later version.
  13
  14   systemd is distributed in the hope that it will be useful, but
  15   WITHOUT ANY WARRANTY; without even the implied warranty of
  16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  17   Lesser General Public License for more details.
  18
  19   You should have received a copy of the GNU Lesser General Public License
  20   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  21 ***/
  22
  23 #include <errno.h>
  24 #include <stdbool.h>
  25 #include <stddef.h>
  26 #include <stdio.h>
  27 #include <syslog.h>
  28
  29 #include "alloc-util.h"
  30 #include "log.h"
  31 #include "macro.h"
  32
  33 /* An abstract parser for simple, line based, shallow configuration files consisting of variable assignments only. */
  34
  35 typedef enum ConfigParseFlags {
  36         CONFIG_PARSE_RELAXED       = 1U << 0,
  37         CONFIG_PARSE_ALLOW_INCLUDE = 1U << 1,
  38         CONFIG_PARSE_WARN          = 1U << 2,
  39         CONFIG_PARSE_REFUSE_BOM    = 1U << 3,
  40 } ConfigParseFlags;
  41
  42 /* Prototype for a parser for a specific configuration setting */
  43 typedef int (*ConfigParserCallback)(const char *unit,
  44                                     const char *filename,
  45                                     unsigned line,
  46                                     const char *section,
  47                                     unsigned section_line,
  48                                     const char *lvalue,
  49                                     int ltype,
  50                                     const char *rvalue,
  51                                     void *data,
  52                                     void *userdata);
  53
  54 /* Wraps information for parsing a specific configuration variable, to
  55  * be stored in a simple array */
  56 typedef struct ConfigTableItem {
  57         const char *section;            /* Section */
  58         const char *lvalue;             /* Name of the variable */
  59         ConfigParserCallback parse;     /* Function that is called to parse the variable's value */
  60         int ltype;                      /* Distinguish different variables passed to the same callback */
  61         void *data;                     /* Where to store the variable's data */
  62 } ConfigTableItem;
  63
  64 /* Wraps information for parsing a specific configuration variable, to
  65  * be stored in a gperf perfect hashtable */
  66 typedef struct ConfigPerfItem {
  67         const char *section_and_lvalue; /* Section + "." + name of the variable */
  68         ConfigParserCallback parse;     /* Function that is called to parse the variable's value */
  69         int ltype;                      /* Distinguish different variables passed to the same callback */
  70         size_t offset;                  /* Offset where to store data, from the beginning of userdata */
  71 } ConfigPerfItem;
  72
  73 /* Prototype for a low-level gperf lookup function */
  74 typedef const ConfigPerfItem* (*ConfigPerfItemLookup)(const char *section_and_lvalue, unsigned length);
  75
  76 /* Prototype for a generic high-level lookup function */
  77 typedef int (*ConfigItemLookup)(
  78                 const void *table,
  79                 const char *section,
  80                 const char *lvalue,
  81                 ConfigParserCallback *func,
  82                 int *ltype,
  83                 void **data,
  84                 void *userdata);
  85
  86 /* Linear table search implementation of ConfigItemLookup, based on
  87  * ConfigTableItem arrays */
  88 int config_item_table_lookup(const void *table, const char *section, const char *lvalue, ConfigParserCallback *func, int *ltype, void **data, void *userdata);
  89
  90 /* gperf implementation of ConfigItemLookup, based on gperf
  91  * ConfigPerfItem tables */
  92 int config_item_perf_lookup(const void *table, const char *section, const char *lvalue, ConfigParserCallback *func, int *ltype, void **data, void *userdata);
  93
  94 int config_parse(
  95                 const char *unit,
  96                 const char *filename,
  97                 FILE *f,
  98                 const char *sections,  /* nulstr */
  99                 ConfigItemLookup lookup,
 100                 const void *table,
 101                 ConfigParseFlags flags,
 102                 void *userdata);
 103
 104 int config_parse_many_nulstr(
 105                 const char *conf_file,      /* possibly NULL */
 106                 const char *conf_file_dirs, /* nulstr */
 107                 const char *sections,       /* nulstr */
 108                 ConfigItemLookup lookup,
 109                 const void *table,
 110                 ConfigParseFlags flags,
 111                 void *userdata);
 112
 113 int config_parse_many(
 114                 const char *conf_file,      /* possibly NULL */
 115                 const char* const* conf_file_dirs,
 116                 const char *dropin_dirname,
 117                 const char *sections,       /* nulstr */
 118                 ConfigItemLookup lookup,
 119                 const void *table,
 120                 ConfigParseFlags flags,
 121                 void *userdata);
 122
 123 /* Generic parsers */
 124 #define GENERIC_PARSER_ARGS \
 125                 const char *unit,                                       \
 126                 const char *filename,                                   \
 127                 unsigned line,                                          \
 128                 const char *section,                                    \
 129                 unsigned section_line,                                  \
 130                 const char *lvalue,                                     \
 131                 int ltype,                                              \
 132                 const char *rvalue,                                     \
 133                 void *data,                                             \
 134                 void *userdata
 135 int config_parse_int(GENERIC_PARSER_ARGS);
 136 int config_parse_unsigned(GENERIC_PARSER_ARGS);
 137 int config_parse_long(GENERIC_PARSER_ARGS);
 138 int config_parse_uint8(GENERIC_PARSER_ARGS);
 139 int config_parse_uint16(GENERIC_PARSER_ARGS);
 140 int config_parse_uint32(GENERIC_PARSER_ARGS);
 141 int config_parse_uint64(GENERIC_PARSER_ARGS);
 142 int config_parse_double(GENERIC_PARSER_ARGS);
 143 int config_parse_iec_size(GENERIC_PARSER_ARGS);
 144 int config_parse_si_size(GENERIC_PARSER_ARGS);
 145 int config_parse_iec_uint64(GENERIC_PARSER_ARGS);
 146 int config_parse_bool(GENERIC_PARSER_ARGS);
 147 int config_parse_tristate(GENERIC_PARSER_ARGS);
 148 int config_parse_string(GENERIC_PARSER_ARGS);
 149 int config_parse_path(GENERIC_PARSER_ARGS);
 150 int config_parse_strv(GENERIC_PARSER_ARGS);
 151 int config_parse_sec(GENERIC_PARSER_ARGS);
 152 int config_parse_nsec(GENERIC_PARSER_ARGS);
 153 int config_parse_mode(GENERIC_PARSER_ARGS);
 154 int config_parse_log_facility(GENERIC_PARSER_ARGS);
 155 int config_parse_log_level(GENERIC_PARSER_ARGS);
 156 int config_parse_signal(GENERIC_PARSER_ARGS);
 157 int config_parse_personality(GENERIC_PARSER_ARGS);
 158 int config_parse_ifname(GENERIC_PARSER_ARGS);
 159 int config_parse_ip_port(GENERIC_PARSER_ARGS);
 160
 161 #define DEFINE_CONFIG_PARSE_ENUM(function,name,type,msg)                \
 162         int function(GENERIC_PARSER_ARGS) {                             \
 163                 type *i = data, x;                                      \
 164                                                                         \
 165                 assert(filename);                                       \
 166                 assert(lvalue);                                         \
 167                 assert(rvalue);                                         \
 168                 assert(data);                                           \
 169                                                                         \
 170                 if ((x = name##_from_string(rvalue)) < 0) {             \
 171                         log_syntax(unit, LOG_ERR, filename, line, -x,   \
 172                                    msg ", ignoring: %s", rvalue);       \
 173                         return 0;                                       \
 174                 }                                                       \
 175                                                                         \
 176                 *i = x;                                                 \
 177                 return 0;                                               \
 178         }
 179
 180 #define DEFINE_CONFIG_PARSE_ENUMV(function,name,type,invalid,msg)              \
 181         int function(GENERIC_PARSER_ARGS) {                                    \
 182                 type **enums = data, x, *ys;                                   \
 183                 _cleanup_free_ type *xs = NULL;                                \
 184                 const char *word, *state;                                      \
 185                 size_t l, i = 0;                                               \
 186                                                                                \
 187                 assert(filename);                                              \
 188                 assert(lvalue);                                                \
 189                 assert(rvalue);                                                \
 190                 assert(data);                                                  \
 191                                                                                \
 192                 xs = new0(type, 1);                                            \
 193                 if (!xs)                                                       \
 194                         return -ENOMEM;                                        \
 195                                                                                \
 196                 *xs = invalid;                                                 \
 197                                                                                \
 198                 FOREACH_WORD(word, l, rvalue, state) {                         \
 199                         _cleanup_free_ char *en = NULL;                        \
 200                         type *new_xs;                                          \
 201                                                                                \
 202                         en = strndup(word, l);                                 \
 203                         if (!en)                                               \
 204                                 return -ENOMEM;                                \
 205                                                                                \
 206                         if ((x = name##_from_string(en)) < 0) {                \
 207                                 log_syntax(unit, LOG_ERR, filename, line,      \
 208                                        -x, msg ", ignoring: %s", en);          \
 209                                 continue;                                      \
 210                         }                                                      \
 211                                                                                \
 212                         for (ys = xs; x != invalid && *ys != invalid; ys++) {  \
 213                                 if (*ys == x) {                                \
 214                                         log_syntax(unit, LOG_ERR, filename,    \
 215                                               line, -x,                        \
 216                                               "Duplicate entry, ignoring: %s", \
 217                                               en);                             \
 218                                         x = invalid;                           \
 219                                 }                                              \
 220                         }                                                      \
 221                                                                                \
 222                         if (x == invalid)                                      \
 223                                 continue;                                      \
 224                                                                                \
 225                         *(xs + i) = x;                                         \
 226                         new_xs = realloc(xs, (++i + 1) * sizeof(type));        \
 227                         if (new_xs)                                            \
 228                                 xs = new_xs;                                   \
 229                         else                                                   \
 230                                 return -ENOMEM;                                \
 231                                                                                \
 232                         *(xs + i) = invalid;                                   \
 233                 }                                                              \
 234                                                                                \
 235                 free(*enums);                                                  \
 236                 *enums = xs;                                                   \
 237                 xs = NULL;                                                     \
 238                                                                                \
 239                 return 0;                                                      \
 240         }