/* $Id: cfg.c,v 1.20 2004/01/07 10:15:41 reinelt Exp $^ * * config file stuff * * Copyright 1999, 2000 Michael Reinelt * * This file is part of LCD4Linux. * * LCD4Linux 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; either version 2, or (at your option) * any later version. * * LCD4Linux 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., 675 Mass Ave, Cambridge, MA 02139, USA. * * * $Log: cfg.c,v $ * Revision 1.20 2004/01/07 10:15:41 reinelt * small glitch in evaluator fixed * made config table sorted and access with bsearch(), * which should be much faster * * Revision 1.19 2003/12/19 05:35:14 reinelt * renamed 'client' to 'plugin' * * Revision 1.18 2003/10/11 06:01:52 reinelt * * renamed expression.{c,h} to client.{c,h} * added config file client * new functions 'AddNumericVariable()' and 'AddStringVariable()' * new parameter '-i' for interactive mode * * Revision 1.17 2003/10/05 17:58:50 reinelt * libtool junk; copyright messages cleaned up * * Revision 1.16 2003/09/09 06:54:43 reinelt * new function 'cfg_number()' * * Revision 1.15 2003/08/24 05:17:58 reinelt * liblcd4linux patch from Patrick Schemitz * * Revision 1.14 2003/08/14 03:47:40 reinelt * remove PID file if driver initialisation fails * * Revision 1.13 2003/02/22 07:53:10 reinelt * cfg_get(key,defval) * * Revision 1.12 2001/03/09 12:14:24 reinelt * * minor cleanups * * Revision 1.11 2001/03/08 15:25:38 ltoetsch * improved exec * * Revision 1.10 2001/03/07 18:10:21 ltoetsch * added e(x)ec commands * * Revision 1.9 2000/08/10 09:44:09 reinelt * * new debugging scheme: error(), info(), debug() * uses syslog if in daemon mode * * Revision 1.8 2000/07/31 06:46:35 reinelt * * eliminated some compiler warnings with glibc * * Revision 1.7 2000/04/15 11:13:54 reinelt * * added '-d' (debugging) switch * added several debugging messages * removed config entry 'Delay' for HD44780 driver * delay loop for HD44780 will be calibrated automatically * * Revision 1.6 2000/04/03 04:46:38 reinelt * * added '-c key=val' option * * Revision 1.5 2000/03/28 07:22:15 reinelt * * version 0.95 released * X11 driver up and running * minor bugs fixed * * Revision 1.4 2000/03/26 20:00:44 reinelt * * README.Raster added * * Revision 1.3 2000/03/26 19:03:52 reinelt * * more Pixmap renaming * quoting of '#' in config file * * Revision 1.2 2000/03/10 17:36:02 reinelt * * first unstable but running release * * Revision 1.1 2000/03/10 11:40:47 reinelt * *** empty log message *** * * Revision 1.3 2000/03/07 11:01:34 reinelt * * system.c cleanup * * Revision 1.2 2000/03/06 06:04:06 reinelt * * minor cleanups * */ /* * exported functions: * * cfg_init (source) * read configuration from source * returns 0 if successful * returns -1 in case of an error * * cfg_source (void) * returns the file the configuration was read from * * cfg_cmd (arg) * allows us to overwrite entries in the * config-file from the command line. * arg is 'key=value' * cfg_cmd can be called _before_ cfg_read() * returns 0 if ok, -1 if arg cannot be parsed * * cfg_get (key, defval) * return the a value for a given key * or if key does not exist * */ #include #include #include #include #include #include #include #include "debug.h" #include "cfg.h" #include "plugin.h" typedef struct { char *key; char *val; int lock; } ENTRY; static char *Config_File=NULL; static ENTRY *Config=NULL; static int nConfig=0; // bsearch compare function for config entries static int c_lookup (const void *a, const void *b) { char *key=(char*)a; ENTRY *entry=(ENTRY*)b; return strcasecmp(key, entry->key); } // qsort compare function for variables static int c_sort (const void *a, const void *b) { ENTRY *ea=(ENTRY*)a; ENTRY *eb=(ENTRY*)b; return strcasecmp(ea->key, eb->key); } static char *strip (char *s, int strip_comments) { char *p; while (isblank(*s)) s++; for (p=s; *p; p++) { if (*p=='"') do p++; while (*p && *p!='\n' && *p!='"'); if (*p=='\'') do p++; while (*p && *p!='\n' && *p!='\''); if (*p=='\n' || (strip_comments && *p=='#' && (p==s || *(p-1)!='\\'))) { *p='\0'; break; } } for (p--; p>s && isblank(*p); p--) *p='\0'; return s; } static char *dequote (char *string) { char *s=string; char *p=string; do { if (*s=='\\' && *(s+1)=='#') { *p++=*++s; } else { *p++=*s; } } while (*s++); return string; } static void cfg_add (char *key, char *val, int lock) { ENTRY *entry; entry=bsearch(key, Config, nConfig, sizeof(ENTRY), c_lookup); if (entry!=NULL) { if (entry->lock>lock) return; if (entry->val) free (entry->val); entry->val=dequote(strdup(val)); return; } nConfig++; Config=realloc(Config, nConfig*sizeof(ENTRY)); Config[nConfig-1].key=strdup(key); Config[nConfig-1].val=dequote(strdup(val)); Config[nConfig-1].lock=lock; qsort(Config, nConfig, sizeof(ENTRY), c_sort); } int l4l_cfg_cmd (char *arg) { char *key, *val; char buffer[256]; strncpy (buffer, arg, sizeof(buffer)); key=strip(buffer, 0); for (val=key; *val; val++) { if (*val=='=') { *val++='\0'; break; } } if (*key=='\0' || *val=='\0') return -1; cfg_add (key, val, 1); return 0; } char *l4l_cfg_get (char *key, char *defval) { ENTRY *entry; entry=bsearch(key, Config, nConfig, sizeof(ENTRY), c_lookup); if (entry!=NULL) return entry->val; return defval; } int l4l_cfg_number (char *key, int defval, int min, int max, int *value) { char *s, *e; s=cfg_get(key, NULL); if (s==NULL) { *value=defval; return 0; } *value=strtol(s, &e, 0); if (*e!='\0') { error ("bad %s entry '%s' in %s", key, s, cfg_source()); return -1; } if (*valuemax) { error ("bad %s value '%s' in %s, maximum is %d", key, s, cfg_source(), max); return -1; } return 0; } static int check_cfg_source(char *file) { /* as passwords and commands are stored in the config file, * we will check that: * - file is a normal file (or /dev/null) * - file owner is owner of program * - file is not accessible by group * - file is not accessible by other */ struct stat stbuf; uid_t uid, gid; int error; uid = geteuid(); gid = getegid(); if (stat(file, &stbuf) == -1) { error ("stat(%s) failed: %s", file, strerror(errno)); return -1; } if (S_ISCHR(stbuf.st_mode) && strcmp(file, "/dev/null") == 0) return 0; error=0; if (!S_ISREG(stbuf.st_mode)) { error ("security error: '%s' is not a regular file", file); error=-1; } if (stbuf.st_uid != uid || stbuf.st_gid != gid) { error ("security error: owner and/or group of '%s' don't match", file); error=-1; } if (stbuf.st_mode & S_IRWXG || stbuf.st_mode & S_IRWXO) { error ("security error: group or other have access to '%s'", file); error=-1; } return error; } static void cfg_plugin (RESULT *result, RESULT *arg1) { char *value=cfg_get(R2S(arg1), ""); SetResult(&result, R_STRING, value); } int l4l_cfg_init (char *file) { FILE *stream; char buffer[256]; char *line, *p, *s; if (check_cfg_source(file) == -1) { error("config file '%s' is insecure, aborting", file); return -1; } stream=fopen (file, "r"); if (stream==NULL) { error ("open(%s) failed: %s", file, strerror(errno)); return -1; } if (Config_File) free (Config_File); Config_File=strdup(file); while ((line=fgets(buffer,256,stream))!=NULL) { if (*(line=strip(line, 1))=='\0') continue; for (p=line; *p; p++) { if (isblank(*p)) { *p++='\0'; break; } } p=strip(p, 1); if (*p) for (s=p; *(s+1); s++); else s=p; if (*p=='"' && *s=='"') { *s='\0'; p++; } else if (*p=='\'' && *s=='\'') { *s='\0'; p++; } cfg_add (line, p, 0); } fclose (stream); // register as a plugin AddFunction ("cfg", 1, cfg_plugin); return 0; } char *l4l_cfg_source (void) { if (Config_File) return Config_File; else return ""; } int (*cfg_init) (char *source) = l4l_cfg_init; char *(*cfg_source) (void) = l4l_cfg_source; int (*cfg_cmd) (char *arg) = l4l_cfg_cmd; char *(*cfg_get) (char *key, char *defval) = l4l_cfg_get; int (*cfg_number) (char *key, int defval, int min, int max, int *value) = l4l_cfg_number;