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 int config_parse_join_controllers(GENERIC_PARSER_ARGS);
 161
 162 #define DEFINE_CONFIG_PARSE_ENUM(function,name,type,msg)                \
 163         int function(GENERIC_PARSER_ARGS) {                             \
 164                 type *i = data, x;                                      \
 165                                                                         \
 166                 assert(filename);                                       \
 167                 assert(lvalue);                                         \
 168                 assert(rvalue);                                         \
 169                 assert(data);                                           \
 170                                                                         \
 171                 if ((x = name##_from_string(rvalue)) < 0) {             \
 172                         log_syntax(unit, LOG_ERR, filename, line, -x,   \
 173                                    msg ", ignoring: %s", rvalue);       \
 174                         return 0;                                       \
 175                 }                                                       \
 176                                                                         \
 177                 *i = x;                                                 \
 178                 return 0;                                               \
 179         }
 180
 181 #define DEFINE_CONFIG_PARSE_ENUMV(function,name,type,invalid,msg)              \
 182         int function(GENERIC_PARSER_ARGS) {                                    \
 183                 type **enums = data, x, *ys;                                   \
 184                 _cleanup_free_ type *xs = NULL;                                \
 185                 const char *word, *state;                                      \
 186                 size_t l, i = 0;                                               \
 187                                                                                \
 188                 assert(filename);                                              \
 189                 assert(lvalue);                                                \
 190                 assert(rvalue);                                                \
 191                 assert(data);                                                  \
 192                                                                                \
 193                 xs = new0(type, 1);                                            \
 194                 if (!xs)                                                       \
 195                         return -ENOMEM;                                        \
 196                                                                                \
 197                 *xs = invalid;                                                 \
 198                                                                                \
 199                 FOREACH_WORD(word, l, rvalue, state) {                         \
 200                         _cleanup_free_ char *en = NULL;                        \
 201                         type *new_xs;                                          \
 202                                                                                \
 203                         en = strndup(word, l);                                 \
 204                         if (!en)                                               \
 205                                 return -ENOMEM;                                \
 206                                                                                \
 207                         if ((x = name##_from_string(en)) < 0) {                \
 208                                 log_syntax(unit, LOG_ERR, filename, line,      \
 209                                        -x, msg ", ignoring: %s", en);          \
 210                                 continue;                                      \
 211                         }                                                      \
 212                                                                                \
 213                         for (ys = xs; x != invalid && *ys != invalid; ys++) {  \
 214                                 if (*ys == x) {                                \
 215                                         log_syntax(unit, LOG_ERR, filename,    \
 216                                               line, -x,                        \
 217                                               "Duplicate entry, ignoring: %s", \
 218                                               en);                             \
 219                                         x = invalid;                           \
 220                                 }                                              \
 221                         }                                                      \
 222                                                                                \
 223                         if (x == invalid)                                      \
 224                                 continue;                                      \
 225                                                                                \
 226                         *(xs + i) = x;                                         \
 227                         new_xs = realloc(xs, (++i + 1) * sizeof(type));        \
 228                         if (new_xs)                                            \
 229                                 xs = new_xs;                                   \
 230                         else                                                   \
 231                                 return -ENOMEM;                                \
 232                                                                                \
 233                         *(xs + i) = invalid;                                   \
 234                 }                                                              \
 235                                                                                \
 236                 free(*enums);                                                  \
 237                 *enums = xs;                                                   \
 238                 xs = NULL;                                                     \
 239                                                                                \
 240                 return 0;                                                      \
 241         }