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_strdup(byte *s)
  47 {
  48         return mp_strdup(cfpool, s);
  49 }
  50
  51 void cf_register(struct cfitem *items)
  52 {
  53         if(items[0].type!=CT_SECTION && items[0].type!=CT_INCOMPLETE_SECTION)
  54                 die("cf_register: Invalid section type");
  55         items[0].var=cfsection;
  56         cfsection=items;
  57 }
  58
  59 int cf_item_count(void)
  60 {
  61         struct cfitem *sect, *item;
  62         int count = 0;
  63         for (sect = cfsection; sect; sect = sect->var)
  64                 for (item = sect+1; item->type; item++)
  65                         count++;
  66         return count;
  67 }
  68
  69 struct cfitem *cf_get_item(byte *sect, byte *name)
  70 {
  71         struct cfitem *item, *section;
  72
  73         item=cfsection;
  74         while(item && strcasecmp(item->name,sect))
  75                 item=item->var;
  76         if(!item)       /* unknown section */
  77                 return NULL;
  78         section = item;
  79
  80         for(item++; item->type && strcasecmp(item->name,name); item++);
  81         if (!item->type && section->type == CT_INCOMPLETE_SECTION)
  82                 return NULL;
  83
  84         return item;    /* item->type == 0 if not found */
  85 }
  86
  87 struct unit {
  88         uns name;                       /* One-letter name of the unit */
  89         uns num, den;                   /* Fraction */
  90 };
  91
  92 static const struct unit units[] = {
  93         { 'd', 86400, 1 },
  94         { 'h', 3600, 1 },
  95         { 'k', 1000, 1 },
  96         { 'm', 1000000, 1 },
  97         { 'g', 1000000000, 1 },
  98         { 'K', 1024, 1 },
  99         { 'M', 1048576, 1 },
 100         { 'G', 1073741824, 1 },
 101         { '%', 1, 100 },
 102         { 0, 0, 0 }
 103 };
 104
 105 static const struct unit *cf_lookup_unit(byte *value, byte *end, char **msg)
 106 {
 107         if (end && *end) {
 108                 if (end == value || end[1] || *end >= '0' && *end <= '9')
 109                         *msg = "Invalid number";
 110                 else {
 111                         for (const struct unit *u=units; u->name; u++)
 112                                 if (u->name == *end)
 113                                         return u;
 114                         *msg = "Invalid unit";
 115                 }
 116         }
 117         return NULL;
 118 }
 119
 120 static char cf_rngerr[] = "Number out of range";
 121
 122 byte *cf_parse_int(byte *value, uns *varp)
 123 {
 124         char *msg = NULL;
 125         const struct unit *u;
 126
 127         if (!*value)
 128                 msg = "Missing number";
 129         else {
 130                 errno = 0;
 131                 char *end;
 132                 uns x = strtoul(value, &end, 0);
 133                 if (errno == ERANGE)
 134                         msg = cf_rngerr;
 135                 else if (u = cf_lookup_unit(value, end, &msg)) {
 136                         u64 y = (u64)x * u->num;
 137                         if (y % u->den)
 138                                 msg = "Number is not an integer";
 139                         else {
 140                                 y /= u->den;
 141                                 if (y > 0xffffffff)
 142                                         msg = cf_rngerr;
 143                                 *varp = y;
 144                         }
 145                 } else
 146                         *varp = x;
 147         }
 148         return msg;
 149 }
 150
 151 byte *cf_parse_u64(byte *value, u64 *varp)
 152 {
 153         char *msg = NULL;
 154         const struct unit *u;
 155
 156         if (!*value)
 157                 msg = "Missing number";
 158         else {
 159                 errno = 0;
 160                 char *end;
 161                 u64 x = strtoull(value, &end, 0);
 162                 if (errno == ERANGE)
 163                         msg = cf_rngerr;
 164                 else if (u = cf_lookup_unit(value, end, &msg)) {
 165                         if (x > ~(u64)0 / u->num)
 166                                 msg = "Number out of range";
 167                         else {
 168                                 x *= u->num;
 169                                 if (x % u->den)
 170                                         msg = "Number is not an integer";
 171                                 else
 172                                         *varp = x / u->den;
 173                         }
 174                 } else
 175                         *varp = x;
 176         }
 177         return msg;
 178 }
 179
 180 byte *cf_parse_double(byte *value, double *varp)
 181 {
 182         char *msg = NULL;
 183         const struct unit *u;
 184
 185         if (!*value)
 186                 msg = "Missing number";
 187         else {
 188                 errno = 0;
 189                 char *end;
 190                 double x = strtoul(value, &end, 0);
 191                 if (errno == ERANGE)
 192                         msg = cf_rngerr;
 193                 else if (u = cf_lookup_unit(value, end, &msg))
 194                         *varp = x * u->num / u->den;
 195                 else
 196                         *varp = x;
 197         }
 198         return msg;
 199 }
 200
 201 byte *cf_set_item(byte *sect, byte *name, byte *value)
 202 {
 203         struct cfitem *item;
 204         byte *msg=NULL;
 205
 206         if (!*sect)
 207                 return "Empty section name";
 208         item=cf_get_item(sect,name);
 209         if(!item)       /* ignore unknown section */
 210                 return NULL;
 211
 212         switch(item->type){
 213                 case CT_INT:
 214                         msg = cf_parse_int(value, (uns *) item->var);
 215                         break;
 216                 case CT_STRING:
 217                         *((byte **) item->var) = cfg_strdup(value);
 218                         break;
 219                 case CT_FUNCTION:
 220                         msg = ((ci_func) item->var)(item, cfg_strdup(value));
 221                         break;
 222                 case CT_DOUBLE:
 223                         msg = cf_parse_double(value, (double *) item->var);
 224                         break;
 225                 case CT_U64:
 226                         msg = cf_parse_u64(value, (u64 *) item->var);
 227                         break;
 228                 default:
 229                         msg = "Unknown keyword";
 230         }
 231
 232         return msg;
 233 }
 234
 235 static int cf_subread(byte *filename,int level)
 236 {
 237         int fd;
 238         struct fastbuf *b;
 239         byte def_section[BUFFER];
 240         int line;
 241         byte *msg=NULL;
 242
 243         if(level>=MAX_LEVEL){
 244                 log(L_ERROR,"Too many (%d) nested files when reading %s",level,filename);
 245                 return 0;
 246         }
 247
 248         fd=open(filename,O_RDONLY, 0666);
 249         if(fd<0){
 250                 log(L_ERROR,"Cannot open configuration file %s: %m",filename);
 251                 return 0;
 252         }
 253         b=bfdopen(fd,4096);
 254
 255         def_section[0]=0;
 256         line=0;
 257         while(1){
 258                 byte buf[BUFFER];
 259                 byte *c;
 260
 261                 if(!bgets(b,buf,BUFFER))
 262                         break;
 263                 line++;
 264
 265                 c=buf+strlen(buf);
 266                 while(c>buf && Cspace(c[-1]))
 267                         *--c=0;
 268                 c=buf;
 269                 while(*c && Cspace(*c))
 270                         c++;
 271                 if(!*c || *c=='#')
 272                         continue;
 273
 274                 if(*c=='['){
 275                         strcpy(def_section,c+1);
 276                         c=strchr(def_section,']');
 277                         if(c){
 278                                 *c=0;
 279                                 if(c[1]){
 280                                         msg="Garbage after ]";
 281                                         break;
 282                                 }
 283                         }else{
 284                                 msg="Missing ]";
 285                                 break;
 286                         }
 287
 288                 }else{
 289                         byte *sect,*name,*value;
 290
 291                         name=c;
 292                         while(*c && !Cspace(*c))
 293                                 c++;
 294                         while(*c && Cspace(*c))
 295                                 *c++=0;
 296                         value=c;
 297
 298                         if(!strcasecmp(name,"include")){
 299                                 if(!cf_subread(value,level+1)){
 300                                         msg="Included from here";
 301                                         break;
 302                                 }
 303                         }else{
 304                                 c=strchr(name,'.');
 305                                 if(!c)
 306                                         sect=def_section;
 307                                 else{
 308                                         sect=name;
 309                                         *c++=0;
 310                                         name=c;
 311                                 }
 312
 313                                 msg=cf_set_item(sect,name,value);
 314                         }
 315                         if(msg)
 316                                 break;
 317                 }
 318
 319         }       /* for every line */
 320
 321         if(msg)
 322                 log(L_ERROR,"%s, line %d: %s",filename,line,msg);
 323         bclose(b);
 324         return !msg;
 325 }
 326
 327 void cf_read(byte *filename)
 328 {
 329         if(!cf_subread(filename,0))
 330                 die("Reading config file %s failed",filename);
 331         cfdeffile = NULL;
 332 }
 333
 334 static void cf_opt_S(void)
 335 {
 336         byte *sect,*name,*value;
 337         byte *c;
 338         byte *msg=NULL;
 339         byte arg[strlen(optarg)+1];
 340
 341         strcpy(arg, optarg);
 342         name = arg;
 343         c=strchr(name,'=');
 344         if(!c){
 345                 msg="Missing argument";
 346                 sect=value="";
 347         }else{
 348                 *c++=0;
 349                 value=c;
 350
 351                 c=strchr(name,'.');
 352                 if(!c)
 353                         sect="";
 354                 else{
 355                         sect=name;
 356                         *c++=0;
 357                         name=c;
 358                 }
 359
 360                 if (cfdeffile)
 361                         cf_read(cfdeffile);
 362                 msg=cf_set_item(sect,name,value);
 363         }
 364         if(msg)
 365                 die("Invalid command line argument -S%s.%s=%s: %s",sect,name,value,msg);
 366
 367 }
 368
 369 int cf_getopt(int argc,char * const argv[],
 370                 const char *shortopts,const struct option *longopts,
 371                 int *longindex)
 372 {
 373         int res;
 374         static int other_options;
 375
 376         do{
 377                 res=getopt_long(argc,argv,shortopts,longopts,longindex);
 378                 if(res == 'S' || res == 'C') {
 379                         if(other_options)
 380                                 die("The -S and -C options must precede all other arguments");
 381                 }
 382                 if(res=='S'){
 383                         cf_opt_S();
 384                 }else if(res=='C'){
 385                         cf_read(optarg);
 386                 }else{
 387                         /* unhandled option or end of options */
 388                         if(cfdeffile)
 389                                 cf_read(cfdeffile);
 390                         other_options++;
 391                         return res;
 392                 }
 393         }while(1);
 394 }