lib/conf.c

   1 /*
   2  *      Sherlock Library -- Reading of configuration files
   3  *
   4  *      (c) 2001 Robert Spalek <robert@ucw.cz>
   5  *      (c) 2003 Martin Mares <mj@ucw.cz>
   6  *
   7  *      This software may be freely distributed and used according to the terms
   8  *      of the GNU Lesser General Public License.
   9  */
  10
  11 #include "lib/lib.h"
  12 #include "lib/chartype.h"
  13 #include "lib/fastbuf.h"
  14 #include "lib/pools.h"
  15
  16 #include "lib/conf.h"
  17
  18 #include <stdlib.h>
  19 #include <stdio.h>
  20 #include <string.h>
  21 #include <fcntl.h>
  22 #include <getopt.h>
  23 #include <errno.h>
  24
  25 #define BUFFER          1024
  26 #define MAX_LEVEL       8
  27
  28 static struct cfitem *cfsection;
  29 struct mempool *cfpool;
  30
  31 byte *cfdeffile = DEFAULT_CONFIG;
  32
  33 static void CONSTRUCTOR
  34 conf_init(void)
  35 {
  36         cfpool = mp_new(4096);
  37 }
  38
  39 void *
  40 cfg_malloc(uns size)
  41 {
  42         return mp_alloc(cfpool, size);
  43 }
  44
  45 byte *
  46 cfg_stralloc(byte *s)
  47 {
  48         uns l = strlen(s);
  49         byte *k = cfg_malloc(l + 1);
  50         strcpy(k, s);
  51         return k;
  52 }
  53
  54 void cf_register(struct cfitem *items)
  55 {
  56         if(items[0].type!=CT_SECTION && items[0].type!=CT_INCOMPLETE_SECTION)
  57                 die("cf_register: Invalid section type");
  58         items[0].var=cfsection;
  59         cfsection=items;
  60 }
  61
  62 int cf_item_count(void)
  63 {
  64         struct cfitem *sect, *item;
  65         int count = 0;
  66         for (sect = cfsection; sect; sect = sect->var)
  67                 for (item = sect+1; item->type; item++)
  68                         count++;
  69         return count;
  70 }
  71
  72 struct cfitem *cf_get_item(byte *sect, byte *name)
  73 {
  74         struct cfitem *item, *section;
  75
  76         item=cfsection;
  77         while(item && strcasecmp(item->name,sect))
  78                 item=item->var;
  79         if(!item)       /* unknown section */
  80                 return NULL;
  81         section = item;
  82
  83         for(item++; item->type && strcasecmp(item->name,name); item++);
  84         if (!item->type && section->type == CT_INCOMPLETE_SECTION)
  85                 return NULL;
  86
  87         return item;    /* item->type == 0 if not found */
  88 }
  89
  90 struct unit {
  91         uns name;                       /* One-letter name of the unit */
  92         uns num, den;                   /* Fraction */
  93 };
  94
  95 static const struct unit units[] = {
  96         { 'd', 86400, 1 },
  97         { 'h', 3600, 1 },
  98         { 'k', 1000, 1 },
  99         { 'm', 1000000, 1 },
 100         { 'g', 1000000000, 1 },
 101         { 'K', 1024, 1 },
 102         { 'M', 1048576, 1 },
 103         { 'G', 1073741824, 1 },
 104         { '%', 1, 100 },
 105         { 0, 0, 0 }
 106 };
 107
 108 static const struct unit *cf_lookup_unit(byte *value, byte *end, char **msg)
 109 {
 110         if (end && *end) {
 111                 if (end == value || end[1] || *end >= '0' && *end <= '9')
 112                         *msg = "Invalid number";
 113                 else {
 114                         for (const struct unit *u=units; u->name; u++)
 115                                 if (u->name == *end)
 116                                         return u;
 117                         *msg = "Invalid unit";
 118                 }
 119         }
 120         return NULL;
 121 }
 122
 123 static char cf_rngerr[] = "Number out of range";
 124
 125 byte *cf_parse_int(byte *value, uns *varp)
 126 {
 127         char *msg = NULL;
 128         const struct unit *u;
 129
 130         if (!*value)
 131                 msg = "Missing number";
 132         else {
 133                 errno = 0;
 134                 char *end;
 135                 uns x = strtoul(value, &end, 0);
 136                 if (errno == ERANGE)
 137                         msg = cf_rngerr;
 138                 else if (u = cf_lookup_unit(value, end, &msg)) {
 139                         u64 y = (u64)x * u->num;
 140                         if (y % u->den)
 141                                 msg = "Number is not an integer";
 142                         else {
 143                                 y /= u->den;
 144                                 if (y > 0xffffffff)
 145                                         msg = cf_rngerr;
 146                                 *varp = y;
 147                         }
 148                 } else
 149                         *varp = x;
 150         }
 151         return msg;
 152 }
 153
 154 byte *cf_parse_u64(byte *value, u64 *varp)
 155 {
 156         char *msg = NULL;
 157         const struct unit *u;
 158
 159         if (!*value)
 160                 msg = "Missing number";
 161         else {
 162                 errno = 0;
 163                 char *end;
 164                 u64 x = strtoull(value, &end, 0);
 165                 if (errno == ERANGE)
 166                         msg = cf_rngerr;
 167                 else if (u = cf_lookup_unit(value, end, &msg)) {
 168                         if (x > ~(u64)0 / u->num)
 169                                 msg = "Number out of range";
 170                         else {
 171                                 x *= u->num;
 172                                 if (x % u->den)
 173                                         msg = "Number is not an integer";
 174                                 else
 175                                         *varp = x / u->den;
 176                         }
 177                 } else
 178                         *varp = x;
 179         }
 180         return msg;
 181 }
 182
 183 byte *cf_parse_double(byte *value, double *varp)
 184 {
 185         char *msg = NULL;
 186         const struct unit *u;
 187
 188         if (!*value)
 189                 msg = "Missing number";
 190         else {
 191                 errno = 0;
 192                 char *end;
 193                 double x = strtoul(value, &end, 0);
 194                 if (errno == ERANGE)
 195                         msg = cf_rngerr;
 196                 else if (u = cf_lookup_unit(value, end, &msg))
 197                         *varp = x * u->num / u->den;
 198                 else
 199                         *varp = x;
 200         }
 201         return msg;
 202 }
 203
 204 byte *cf_set_item(byte *sect, byte *name, byte *value)
 205 {
 206         struct cfitem *item;
 207         byte *msg=NULL;
 208
 209         if (!*sect)
 210                 return "Empty section name";
 211         item=cf_get_item(sect,name);
 212         if(!item)       /* ignore unknown section */
 213                 return NULL;
 214
 215         switch(item->type){
 216                 case CT_INT:
 217                         msg = cf_parse_int(value, (uns *) item->var);
 218                         break;
 219                 case CT_STRING:
 220                         *((byte **) item->var) = cfg_stralloc(value);
 221                         break;
 222                 case CT_FUNCTION:
 223                         msg = ((ci_func) item->var)(item, cfg_stralloc(value));
 224                         break;
 225                 case CT_DOUBLE:
 226                         msg = cf_parse_double(value, (double *) item->var);
 227                         break;
 228                 case CT_U64:
 229                         msg = cf_parse_u64(value, (u64 *) item->var);
 230                         break;
 231                 default:
 232                         msg = "Unknown keyword";
 233         }
 234
 235         return msg;
 236 }
 237
 238 static int cf_subread(byte *filename,int level)
 239 {
 240         int fd;
 241         struct fastbuf *b;
 242         byte def_section[BUFFER];
 243         int line;
 244         byte *msg=NULL;
 245
 246         if(level>=MAX_LEVEL){
 247                 log(L_ERROR,"Too many (%d) nested files when reading %s",level,filename);
 248                 return 0;
 249         }
 250
 251         fd=open(filename,O_RDONLY, 0666);
 252         if(fd<0){
 253                 log(L_ERROR,"Cannot open configuration file %s: %m",filename);
 254                 return 0;
 255         }
 256         b=bfdopen(fd,4096);
 257
 258         def_section[0]=0;
 259         line=0;
 260         while(1){
 261                 byte buf[BUFFER];
 262                 byte *c;
 263
 264                 if(!bgets(b,buf,BUFFER))
 265                         break;
 266                 line++;
 267
 268                 c=buf+strlen(buf);
 269                 while(c>buf && Cspace(c[-1]))
 270                         *--c=0;
 271                 c=buf;
 272                 while(*c && Cspace(*c))
 273                         c++;
 274                 if(!*c || *c=='#')
 275                         continue;
 276
 277                 if(*c=='['){
 278                         strcpy(def_section,c+1);
 279                         c=strchr(def_section,']');
 280                         if(c){
 281                                 *c=0;
 282                                 if(c[1]){
 283                                         msg="Garbage after ]";
 284                                         break;
 285                                 }
 286                         }else{
 287                                 msg="Missing ]";
 288                                 break;
 289                         }
 290
 291                 }else{
 292                         byte *sect,*name,*value;
 293
 294                         name=c;
 295                         while(*c && !Cspace(*c))
 296                                 c++;
 297                         while(*c && Cspace(*c))
 298                                 *c++=0;
 299                         value=c;
 300
 301                         if(!strcasecmp(name,"include")){
 302                                 if(!cf_subread(value,level+1)){
 303                                         msg="Included from here";
 304                                         break;
 305                                 }
 306                         }else{
 307                                 c=strchr(name,'.');
 308                                 if(!c)
 309                                         sect=def_section;
 310                                 else{
 311                                         sect=name;
 312                                         *c++=0;
 313                                         name=c;
 314                                 }
 315
 316                                 msg=cf_set_item(sect,name,value);
 317                         }
 318                         if(msg)
 319                                 break;
 320                 }
 321
 322         }       /* for every line */
 323
 324         if(msg)
 325                 log(L_ERROR,"%s, line %d: %s",filename,line,msg);
 326         bclose(b);
 327         return !msg;
 328 }
 329
 330 void cf_read(byte *filename)
 331 {
 332         if(!cf_subread(filename,0))
 333                 die("Reading config file %s failed",filename);
 334         cfdeffile = NULL;
 335 }
 336
 337 int cf_getopt(int argc,char * const argv[],
 338                 const char *shortopts,const struct option *longopts,
 339                 int *longindex)
 340 {
 341         int res;
 342
 343         do{
 344                 res=getopt_long(argc,argv,shortopts,longopts,longindex);
 345                 if(res=='S'){
 346                         byte *sect,*name,*value;
 347                         byte *c;
 348                         byte *msg=NULL;
 349
 350                         name=optarg;
 351                         c=strchr(name,'=');
 352                         if(!c){
 353                                 msg="Missing argument";
 354                                 sect=value="";
 355                         }else{
 356                                 *c++=0;
 357                                 value=c;
 358
 359                                 c=strchr(name,'.');
 360                                 if(!c)
 361                                         sect="";
 362                                 else{
 363                                         sect=name;
 364                                         *c++=0;
 365                                         name=c;
 366                                 }
 367
 368                                 if (cfdeffile)
 369                                         cf_read(cfdeffile);
 370                                 msg=cf_set_item(sect,name,value);
 371                         }
 372                         if(msg)
 373                                 die("Invalid command line argument %s.%s=%s: %s",sect,name,value,msg);
 374
 375                 }else if(res=='C'){
 376                         cf_read(optarg);
 377                 }else{
 378                         /* unhandled option or end of options */
 379                         if(cfdeffile)
 380                                 cf_read(cfdeffile);
 381                         return res;
 382                 }
 383         }while(1);
 384 }