lib/conf.c

   1 /*
   2  *      UCW Library -- Reading of configuration files
   3  *
   4  *      (c) 2001 Robert Spalek <robert@ucw.cz>
   5  *      (c) 2003--2005 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/mempool.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 #ifndef DEFAULT_CONFIG
  32 #define DEFAULT_CONFIG NULL
  33 #endif
  34
  35 byte *cfdeffile = DEFAULT_CONFIG;
  36
  37 static void CONSTRUCTOR
  38 conf_init(void)
  39 {
  40         cfpool = mp_new(4096);
  41 }
  42
  43 void *
  44 cfg_malloc(uns size)
  45 {
  46         return mp_alloc(cfpool, size);
  47 }
  48
  49 void *
  50 cfg_malloc_zero(uns size)
  51 {
  52         return mp_alloc_zero(cfpool, size);
  53 }
  54
  55 byte *
  56 cfg_strdup(byte *s)
  57 {
  58         return mp_strdup(cfpool, s);
  59 }
  60
  61 byte *
  62 cfg_printf(char *fmt, ...)
  63 {
  64         va_list args;
  65         va_start(args, fmt);
  66         byte *res = mp_vprintf(cfpool, fmt, args);
  67         va_end(args);
  68         return res;
  69 }
  70
  71 void cf_register(struct cfitem *items)
  72 {
  73         if(items[0].type!=CT_SECTION && items[0].type!=CT_INCOMPLETE_SECTION)
  74                 die("cf_register: Invalid section type");
  75         items[0].var=cfsection;
  76         cfsection=items;
  77 }
  78
  79 int cf_item_count(void)
  80 {
  81         struct cfitem *sect, *item;
  82         int count = 0;
  83         for (sect = cfsection; sect; sect = sect->var)
  84                 for (item = sect+1; item->type; item++)
  85                         count++;
  86         return count;
  87 }
  88
  89 struct cfitem *cf_get_item(byte *sect, byte *name)
  90 {
  91         struct cfitem *item, *section;
  92
  93         item=cfsection;
  94         while(item && strcasecmp(item->name,sect))
  95                 item=item->var;
  96         if(!item)       /* unknown section */
  97                 return NULL;
  98         section = item;
  99
 100         for(item++; item->type && strcasecmp(item->name,name); item++);
 101         if (!item->type && section->type == CT_INCOMPLETE_SECTION)
 102                 return NULL;
 103
 104         return item;    /* item->type == 0 if not found */
 105 }
 106
 107 struct unit {
 108         uns name;                       /* One-letter name of the unit */
 109         uns num, den;                   /* Fraction */
 110 };
 111
 112 static const struct unit units[] = {
 113         { 'd', 86400, 1 },
 114         { 'h', 3600, 1 },
 115         { 'k', 1000, 1 },
 116         { 'm', 1000000, 1 },
 117         { 'g', 1000000000, 1 },
 118         { 'K', 1024, 1 },
 119         { 'M', 1048576, 1 },
 120         { 'G', 1073741824, 1 },
 121         { '%', 1, 100 },
 122         { 0, 0, 0 }
 123 };
 124
 125 static const struct unit *cf_lookup_unit(byte *value, byte *end, char **msg)
 126 {
 127         if (end && *end) {
 128                 if (end == value || end[1] || *end >= '0' && *end <= '9')
 129                         *msg = "Invalid number";
 130                 else {
 131                         for (const struct unit *u=units; u->name; u++)
 132                                 if (u->name == *end)
 133                                         return u;
 134                         *msg = "Invalid unit";
 135                 }
 136         }
 137         return NULL;
 138 }
 139
 140 static char cf_rngerr[] = "Number out of range";
 141
 142 byte *cf_parse_int(byte *value, uns *varp)
 143 {
 144         char *msg = NULL;
 145         const struct unit *u;
 146
 147         if (!*value)
 148                 msg = "Missing number";
 149         else {
 150                 errno = 0;
 151                 char *end;
 152                 uns x = strtoul(value, &end, 0);
 153                 if (errno == ERANGE)
 154                         msg = cf_rngerr;
 155                 else if (u = cf_lookup_unit(value, end, &msg)) {
 156                         u64 y = (u64)x * u->num;
 157                         if (y % u->den)
 158                                 msg = "Number is not an integer";
 159                         else {
 160                                 y /= u->den;
 161                                 if (y > 0xffffffff)
 162                                         msg = cf_rngerr;
 163                                 *varp = y;
 164                         }
 165                 } else
 166                         *varp = x;
 167         }
 168         return msg;
 169 }
 170
 171 byte *cf_parse_u64(byte *value, u64 *varp)
 172 {
 173         char *msg = NULL;
 174         const struct unit *u;
 175
 176         if (!*value)
 177                 msg = "Missing number";
 178         else {
 179                 errno = 0;
 180                 char *end;
 181                 u64 x = strtoull(value, &end, 0);
 182                 if (errno == ERANGE)
 183                         msg = cf_rngerr;
 184                 else if (u = cf_lookup_unit(value, end, &msg)) {
 185                         if (x > ~(u64)0 / u->num)
 186                                 msg = "Number out of range";
 187                         else {
 188                                 x *= u->num;
 189                                 if (x % u->den)
 190                                         msg = "Number is not an integer";
 191                                 else
 192                                         *varp = x / u->den;
 193                         }
 194                 } else
 195                         *varp = x;
 196         }
 197         return msg;
 198 }
 199
 200 byte *cf_parse_double(byte *value, double *varp)
 201 {
 202         char *msg = NULL;
 203         const struct unit *u;
 204
 205         if (!*value)
 206                 msg = "Missing number";
 207         else {
 208                 errno = 0;
 209                 char *end;
 210                 double x = strtoul(value, &end, 0);
 211                 if (errno == ERANGE)
 212                         msg = cf_rngerr;
 213                 else if (u = cf_lookup_unit(value, end, &msg))
 214                         *varp = x * u->num / u->den;
 215                 else
 216                         *varp = x;
 217         }
 218         return msg;
 219 }
 220
 221 byte *cf_set_item(byte *sect, byte *name, byte *value)
 222 {
 223         struct cfitem *item;
 224         byte *msg=NULL;
 225
 226         if (!*sect)
 227                 return "Empty section name";
 228         item=cf_get_item(sect,name);
 229         if(!item)       /* ignore unknown section */
 230                 return NULL;
 231
 232         switch(item->type){
 233                 case CT_INT:
 234                         msg = cf_parse_int(value, (uns *) item->var);
 235                         break;
 236                 case CT_STRING:
 237                         *((byte **) item->var) = cfg_strdup(value);
 238                         break;
 239                 case CT_FUNCTION:
 240                         msg = ((ci_func) item->var)(item, cfg_strdup(value));
 241                         break;
 242                 case CT_DOUBLE:
 243                         msg = cf_parse_double(value, (double *) item->var);
 244                         break;
 245                 case CT_U64:
 246                         msg = cf_parse_u64(value, (u64 *) item->var);
 247                         break;
 248                 default:
 249                         msg = "Unknown keyword";
 250         }
 251
 252         return msg;
 253 }
 254
 255 static int cf_subread(byte *filename,int level)
 256 {
 257         int fd;
 258         struct fastbuf *b;
 259         byte def_section[BUFFER];
 260         int line;
 261         byte *msg=NULL;
 262
 263         if(level>=MAX_LEVEL){
 264                 log(L_ERROR,"Too many (%d) nested files when reading %s",level,filename);
 265                 return 0;
 266         }
 267
 268         fd=open(filename,O_RDONLY, 0666);
 269         if(fd<0){
 270                 log(L_ERROR,"Cannot open configuration file %s: %m",filename);
 271                 return 0;
 272         }
 273         b=bfdopen(fd,4096);
 274
 275         def_section[0]=0;
 276         line=0;
 277         while(1){
 278                 byte buf[BUFFER];
 279                 byte *c;
 280
 281                 if(!bgets(b,buf,BUFFER))
 282                         break;
 283                 line++;
 284
 285                 c=buf+strlen(buf);
 286                 while(c>buf && Cspace(c[-1]))
 287                         *--c=0;
 288                 c=buf;
 289                 while(*c && Cspace(*c))
 290                         c++;
 291                 if(!*c || *c=='#')
 292                         continue;
 293
 294                 if(*c=='['){
 295                         strcpy(def_section,c+1);
 296                         c=strchr(def_section,']');
 297                         if(c){
 298                                 *c=0;
 299                                 if(c[1]){
 300                                         msg="Garbage after ]";
 301                                         break;
 302                                 }
 303                         }else{
 304                                 msg="Missing ]";
 305                                 break;
 306                         }
 307
 308                 }else{
 309                         byte *sect,*name,*value;
 310
 311                         name=c;
 312                         while(*c && !Cspace(*c))
 313                                 c++;
 314                         while(*c && Cspace(*c))
 315                                 *c++=0;
 316                         value=c;
 317
 318                         if(!strcasecmp(name,"include")){
 319                                 if(!cf_subread(value,level+1)){
 320                                         msg="Included from here";
 321                                         break;
 322                                 }
 323                         }else{
 324                                 c=strchr(name,'.');
 325                                 if(!c)
 326                                         sect=def_section;
 327                                 else{
 328                                         sect=name;
 329                                         *c++=0;
 330                                         name=c;
 331                                 }
 332
 333                                 msg=cf_set_item(sect,name,value);
 334                         }
 335                         if(msg)
 336                                 break;
 337                 }
 338
 339         }       /* for every line */
 340
 341         if(msg)
 342                 log(L_ERROR,"%s, line %d: %s",filename,line,msg);
 343         bclose(b);
 344         return !msg;
 345 }
 346
 347 void cf_read(byte *filename)
 348 {
 349         if(!cf_subread(filename,0))
 350                 die("Reading config file %s failed",filename);
 351         cfdeffile = NULL;
 352 }
 353
 354 static void cf_opt_S(void)
 355 {
 356         byte *sect,*name,*value;
 357         byte *c;
 358         byte *msg=NULL;
 359         byte arg[strlen(optarg)+1];
 360
 361         strcpy(arg, optarg);
 362         name = arg;
 363         c=strchr(name,'=');
 364         if(!c){
 365                 msg="Missing argument";
 366                 sect=value="";
 367         }else{
 368                 *c++=0;
 369                 value=c;
 370
 371                 c=strchr(name,'.');
 372                 if(!c)
 373                         sect="";
 374                 else{
 375                         sect=name;
 376                         *c++=0;
 377                         name=c;
 378                 }
 379
 380                 if (cfdeffile)
 381                         cf_read(cfdeffile);
 382                 msg=cf_set_item(sect,name,value);
 383         }
 384         if(msg)
 385                 die("Invalid command line argument -S%s.%s=%s: %s",sect,name,value,msg);
 386
 387 }
 388
 389 int cf_getopt(int argc,char * const argv[],
 390                 const char *shortopts,const struct option *longopts,
 391                 int *longindex)
 392 {
 393         int res;
 394         static int other_options;
 395
 396         do{
 397                 res=getopt_long(argc,argv,shortopts,longopts,longindex);
 398                 if(res == 'S' || res == 'C') {
 399                         if(other_options)
 400                                 die("The -S and -C options must precede all other arguments");
 401                 }
 402                 if(res=='S'){
 403                         cf_opt_S();
 404                 }else if(res=='C'){
 405                         cf_read(optarg);
 406                 }else{
 407                         /* unhandled option or end of options */
 408                         if(cfdeffile)
 409                                 cf_read(cfdeffile);
 410                         other_options++;
 411                         return res;
 412                 }
 413         }while(1);
 414 }