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         { 'k', 1000, 1 },
  97         { 'm', 1000000, 1 },
  98         { 'g', 1000000000, 1 },
  99         { 'K', 1024, 1 },
 100         { 'M', 1048576, 1 },
 101         { 'G', 1073741824, 1 },
 102         { '%', 1, 100 },
 103         { 0, 0, 0 }
 104 };
 105
 106 static const struct unit *cf_lookup_unit(byte *value, byte *end, char **msg)
 107 {
 108         if (end && *end) {
 109                 if (end == value || end[1] || *end >= '0' && *end <= '9')
 110                         *msg = "Invalid number";
 111                 else {
 112                         for (const struct unit *u=units; u->name; u++)
 113                                 if (u->name == *end)
 114                                         return u;
 115                         *msg = "Invalid unit";
 116                 }
 117         }
 118         return NULL;
 119 }
 120
 121 static char cf_rngerr[] = "Number out of range";
 122
 123 byte *cf_parse_int(byte *value, uns *varp)
 124 {
 125         char *msg = NULL;
 126         const struct unit *u;
 127
 128         if (!*value)
 129                 msg = "Missing number";
 130         else {
 131                 errno = 0;
 132                 char *end;
 133                 uns x = strtoul(value, &end, 0);
 134                 if (errno == ERANGE)
 135                         msg = cf_rngerr;
 136                 else if (u = cf_lookup_unit(value, end, &msg)) {
 137                         u64 y = (u64)x * u->num;
 138                         if (y % u->den)
 139                                 msg = "Number is not an integer";
 140                         else {
 141                                 y /= u->den;
 142                                 if (y > 0xffffffff)
 143                                         msg = cf_rngerr;
 144                                 *varp = y;
 145                         }
 146                 } else
 147                         *varp = x;
 148         }
 149         return msg;
 150 }
 151
 152 byte *cf_parse_double(byte *value, double *varp)
 153 {
 154         char *msg = NULL;
 155         const struct unit *u;
 156
 157         if (!*value)
 158                 msg = "Missing number";
 159         else {
 160                 errno = 0;
 161                 char *end;
 162                 double x = strtoul(value, &end, 0);
 163                 if (errno == ERANGE)
 164                         msg = cf_rngerr;
 165                 else if (u = cf_lookup_unit(value, end, &msg))
 166                         *varp = x * u->num / u->den;
 167                 else
 168                         *varp = x;
 169         }
 170         return msg;
 171 }
 172
 173 byte *cf_set_item(byte *sect, byte *name, byte *value)
 174 {
 175         struct cfitem *item;
 176         byte *msg=NULL;
 177
 178         if (!*sect)
 179                 return "Empty section name";
 180         item=cf_get_item(sect,name);
 181         if(!item)       /* ignore unknown section */
 182                 return NULL;
 183
 184         switch(item->type){
 185                 case CT_INT:
 186                         msg = cf_parse_int(value, (uns *) item->var);
 187                         break;
 188                 case CT_STRING:
 189                         *((byte **) item->var) = cfg_stralloc(value);
 190                         break;
 191                 case CT_FUNCTION:
 192                         msg = ((ci_func) item->var)(item, cfg_stralloc(value));
 193                         break;
 194                 case CT_DOUBLE:
 195                         msg = cf_parse_double(value, (double *) item->var);
 196                         break;
 197                 default:
 198                         msg = "Unknown keyword";
 199         }
 200
 201         return msg;
 202 }
 203
 204 static int cf_subread(byte *filename,int level)
 205 {
 206         int fd;
 207         struct fastbuf *b;
 208         byte def_section[BUFFER];
 209         int line;
 210         byte *msg=NULL;
 211
 212         if(level>=MAX_LEVEL){
 213                 log(L_ERROR,"Too many (%d) nested files when reading %s",level,filename);
 214                 return 0;
 215         }
 216
 217         fd=open(filename,O_RDONLY, 0666);
 218         if(fd<0){
 219                 log(L_ERROR,"Cannot open configuration file %s: %m",filename);
 220                 return 0;
 221         }
 222         b=bfdopen(fd,4096);
 223
 224         def_section[0]=0;
 225         line=0;
 226         while(1){
 227                 byte buf[BUFFER];
 228                 byte *c;
 229
 230                 if(!bgets(b,buf,BUFFER))
 231                         break;
 232                 line++;
 233
 234                 c=buf+strlen(buf);
 235                 while(c>buf && Cspace(c[-1]))
 236                         *--c=0;
 237                 c=buf;
 238                 while(*c && Cspace(*c))
 239                         c++;
 240                 if(!*c || *c=='#')
 241                         continue;
 242
 243                 if(*c=='['){
 244                         strcpy(def_section,c+1);
 245                         c=strchr(def_section,']');
 246                         if(c){
 247                                 *c=0;
 248                                 if(c[1]){
 249                                         msg="Garbage after ]";
 250                                         break;
 251                                 }
 252                         }else{
 253                                 msg="Missing ]";
 254                                 break;
 255                         }
 256
 257                 }else{
 258                         byte *sect,*name,*value;
 259
 260                         name=c;
 261                         while(*c && !Cspace(*c))
 262                                 c++;
 263                         while(*c && Cspace(*c))
 264                                 *c++=0;
 265                         value=c;
 266
 267                         if(!strcasecmp(name,"include")){
 268                                 if(!cf_subread(value,level+1)){
 269                                         msg="Included from here";
 270                                         break;
 271                                 }
 272                         }else{
 273                                 c=strchr(name,'.');
 274                                 if(!c)
 275                                         sect=def_section;
 276                                 else{
 277                                         sect=name;
 278                                         *c++=0;
 279                                         name=c;
 280                                 }
 281
 282                                 msg=cf_set_item(sect,name,value);
 283                         }
 284                         if(msg)
 285                                 break;
 286                 }
 287
 288         }       /* for every line */
 289
 290         if(msg)
 291                 log(L_ERROR,"%s, line %d: %s",filename,line,msg);
 292         bclose(b);
 293         return !msg;
 294 }
 295
 296 void cf_read(byte *filename)
 297 {
 298         if(!cf_subread(filename,0))
 299                 die("Reading config file %s failed",filename);
 300         cfdeffile = NULL;
 301 }
 302
 303 int cf_getopt(int argc,char * const argv[],
 304                 const char *shortopts,const struct option *longopts,
 305                 int *longindex)
 306 {
 307         int res;
 308
 309         do{
 310                 res=getopt_long(argc,argv,shortopts,longopts,longindex);
 311                 if(res=='S'){
 312                         byte *sect,*name,*value;
 313                         byte *c;
 314                         byte *msg=NULL;
 315
 316                         name=optarg;
 317                         c=strchr(name,'=');
 318                         if(!c){
 319                                 msg="Missing argument";
 320                                 sect=value="";
 321                         }else{
 322                                 *c++=0;
 323                                 value=c;
 324
 325                                 c=strchr(name,'.');
 326                                 if(!c)
 327                                         sect="";
 328                                 else{
 329                                         sect=name;
 330                                         *c++=0;
 331                                         name=c;
 332                                 }
 333
 334                                 if (cfdeffile)
 335                                         cf_read(cfdeffile);
 336                                 msg=cf_set_item(sect,name,value);
 337                         }
 338                         if(msg)
 339                                 die("Invalid command line argument %s.%s=%s: %s",sect,name,value,msg);
 340
 341                 }else if(res=='C'){
 342                         cf_read(optarg);
 343                 }else{
 344                         /* unhandled option or end of options */
 345                         if(cfdeffile)
 346                                 cf_read(cfdeffile);
 347                         return res;
 348                 }
 349         }while(1);
 350 }