catopen.c raw

   1  #define _BSD_SOURCE
   2  #include <nl_types.h>
   3  #include <string.h>
   4  #include <stdint.h>
   5  #include <endian.h>
   6  #include <errno.h>
   7  #include <langinfo.h>
   8  #include <locale.h>
   9  #include <sys/mman.h>
  10  #include "libc.h"
  11  
  12  #define V(p) be32toh(*(uint32_t *)(p))
  13  
  14  static nl_catd do_catopen(const char *name)
  15  {
  16  	size_t size;
  17  	const unsigned char *map = __map_file(name, &size);
  18  	/* Size recorded in the file must match file size; otherwise
  19  	 * the information needed to unmap the file will be lost. */
  20  	if (!map || V(map) != 0xff88ff89 || 20+V(map+8) != size) {
  21  		if(map) munmap((void *)map, size);
  22  		errno = ENOENT;
  23  		return (nl_catd)-1;
  24  	}
  25  	return (nl_catd)map;
  26  }
  27  
  28  nl_catd catopen(const char *name, int oflag)
  29  {
  30  	nl_catd catd;
  31  
  32  	if (strchr(name, '/')) return do_catopen(name);
  33  
  34  	char buf[PATH_MAX];
  35  	size_t i;
  36  	const char *path, *lang, *p, *z;
  37  	if (libc.secure || !(path = getenv("NLSPATH"))) {
  38  		errno = ENOENT;
  39  		return (nl_catd)-1;
  40  	}
  41  	lang = oflag ? nl_langinfo(_NL_LOCALE_NAME(LC_MESSAGES)) : getenv("LANG");
  42  	if (!lang) lang = "";
  43  	for (p=path; *p; p=z) {
  44  		i = 0;
  45  		z = __strchrnul(p, ':');
  46  		for (; p<z; p++) {
  47  			const char *v;
  48  			size_t l;
  49  			if (*p!='%') v=p, l=1;
  50  			else switch (*++p) {
  51  			case 'N': v=name; l=strlen(v); break;
  52  			case 'L': v=lang; l=strlen(v); break;
  53  			case 'l': v=lang; l=strcspn(v,"_.@"); break;
  54  			case 't':
  55  				v=__strchrnul(lang,'_');
  56  				if (*v) v++;
  57  				l=strcspn(v,".@");
  58  				break;
  59  			case 'c': v="UTF-8"; l=5; break;
  60  			case '%': v="%"; l=1; break;
  61  			default: v=0;
  62  			}
  63  			if (!v || l >= sizeof buf - i) {
  64  				break;
  65  			}
  66  			memcpy(buf+i, v, l);
  67  			i += l;
  68  		}
  69  		if (!*z && (p<z || !i)) break;
  70  		if (p<z) continue;
  71  		if (*z) z++;
  72  		buf[i] = 0;
  73  		/* Leading : or :: in NLSPATH is same as %N */
  74  		catd = do_catopen(i ? buf : name);
  75  		if (catd != (nl_catd)-1) return catd;
  76  	}
  77  	errno = ENOENT;
  78  	return (nl_catd)-1;
  79  }
  80