src/conf-parser.h

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 #ifndef fooconfparserhfoo
   4 #define fooconfparserhfoo
   5
   6 /***
   7   This file is part of systemd.
   8
   9   Copyright 2010 Lennart Poettering
  10
  11   systemd is free software; you can redistribute it and/or modify it
  12   under the terms of the GNU General Public License as published by
  13   the Free Software Foundation; either version 2 of the License, or
  14   (at your option) any later version.
  15
  16   systemd is distributed in the hope that it will be useful, but
  17   WITHOUT ANY WARRANTY; without even the implied warranty of
  18   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  19   General Public License for more details.
  20
  21   You should have received a copy of the GNU General Public License
  22   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  23 ***/
  24
  25 #include <stdio.h>
  26 #include <stdbool.h>
  27
  28 /* An abstract parser for simple, line based, shallow configuration
  29  * files consisting of variable assignments only. */
  30
  31 /* Prototype for a parser for a specific configuration setting */
  32 typedef int (*ConfigParserCallback)(
  33                 const char *filename,
  34                 unsigned line,
  35                 const char *section,
  36                 const char *lvalue,
  37                 int ltype,
  38                 const char *rvalue,
  39                 void *data,
  40                 void *userdata);
  41
  42 /* Wraps information for parsing a specific configuration variable, to
  43  * be stored in a simple array */
  44 typedef struct ConfigTableItem {
  45         const char *section;            /* Section */
  46         const char *lvalue;             /* Name of the variable */
  47         ConfigParserCallback parse;     /* Function that is called to parse the variable's value */
  48         int ltype;                      /* Distinguish different variables passed to the same callback */
  49         void *data;                     /* Where to store the variable's data */
  50 } ConfigTableItem;
  51
  52 /* Wraps information for parsing a specific configuration variable, to
  53  * ve srored in a gperf perfect hashtable */
  54 typedef struct ConfigPerfItem {
  55         const char *section_and_lvalue; /* Section + "." + name of the variable */
  56         ConfigParserCallback parse;     /* Function that is called to parse the variable's value */
  57         int ltype;                      /* Distinguish different variables passed to the same callback */
  58         size_t offset;                  /* Offset where to store data, from the beginning of userdata */
  59 } ConfigPerfItem;
  60
  61 /* Prototype for a low-level gperf lookup function */
  62 typedef const ConfigPerfItem* (*ConfigPerfItemLookup)(const char *section_and_lvalue, unsigned length);
  63
  64 /* Prototype for a generic high-level lookup function */
  65 typedef int (*ConfigItemLookup)(
  66                 void *table,
  67                 const char *section,
  68                 const char *lvalue,
  69                 ConfigParserCallback *func,
  70                 int *ltype,
  71                 void **data,
  72                 void *userdata);
  73
  74 /* Linear table search implementation of ConfigItemLookup, based on
  75  * ConfigTableItem arrays */
  76 int config_item_table_lookup(void *table, const char *section, const char *lvalue, ConfigParserCallback *func, int *ltype, void **data, void *userdata);
  77
  78 /* gperf implementation of ConfigItemLookup, based on gperf
  79  * ConfigPerfItem tables */
  80 int config_item_perf_lookup(void *table, const char *section, const char *lvalue, ConfigParserCallback *func, int *ltype, void **data, void *userdata);
  81
  82 int config_parse(
  83                 const char *filename,
  84                 FILE *f,
  85                 const char *sections,  /* nulstr */
  86                 ConfigItemLookup lookup,
  87                 void *table,
  88                 bool relaxed,
  89                 void *userdata);
  90
  91 /* Generic parsers */
  92 int config_parse_int(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
  93 int config_parse_unsigned(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
  94 int config_parse_long(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
  95 int config_parse_uint64(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
  96 int config_parse_size(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
  97 int config_parse_bool(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
  98 int config_parse_tristate(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
  99 int config_parse_string(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 100 int config_parse_path(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 101 int config_parse_strv(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 102 int config_parse_path_strv(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 103 int config_parse_usec(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 104 int config_parse_mode(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 105 int config_parse_bytes(const char *filename, unsigned line, const char *section, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 106
 107 #define DEFINE_CONFIG_PARSE_ENUM(function,name,type,msg)                \
 108         int function(                                                   \
 109                         const char *filename,                           \
 110                         unsigned line,                                  \
 111                         const char *section,                            \
 112                         const char *lvalue,                             \
 113                         int ltype,                                      \
 114                         const char *rvalue,                             \
 115                         void *data,                                     \
 116                         void *userdata) {                               \
 117                                                                         \
 118                 type *i = data, x;                                      \
 119                                                                         \
 120                 assert(filename);                                       \
 121                 assert(lvalue);                                         \
 122                 assert(rvalue);                                         \
 123                 assert(data);                                           \
 124                                                                         \
 125                 if ((x = name##_from_string(rvalue)) < 0) {             \
 126                         log_error("[%s:%u] " msg ", ignoring: %s", filename, line, rvalue); \
 127                         return 0;                                       \
 128                 }                                                       \
 129                                                                         \
 130                 *i = x;                                                 \
 131                                                                         \
 132                 return 0;                                               \
 133         }
 134
 135 #endif