lib/idcache.c

   1 /*
   2  * No copyright is claimed.  This code is in the public domain; do with
   3  * it what you wish.
   4  *
   5  * Written by Karel Zak <kzak@redhat.com>
   6  */
   7 #include <wchar.h>
   8 #include <pwd.h>
   9 #include <grp.h>
  10 #include <sys/types.h>
  11
  12 #include "c.h"
  13 #include "idcache.h"
  14
  15 struct identry *get_id(struct idcache *ic, unsigned long int id)
  16 {
  17         struct identry *ent;
  18
  19         if (!ic)
  20                 return NULL;
  21
  22         for (ent = ic->ent; ent; ent = ent->next) {
  23                 if (ent->id == id)
  24                         return ent;
  25         }
  26
  27         return NULL;
  28 }
  29
  30 struct idcache *new_idcache(void)
  31 {
  32         return calloc(1, sizeof(struct idcache));
  33 }
  34
  35 void free_idcache(struct idcache *ic)
  36 {
  37         struct identry *ent = ic->ent;
  38
  39         while (ent) {
  40                 struct identry *next = ent->next;
  41                 free(ent->name);
  42                 free(ent);
  43                 ent = next;
  44         }
  45
  46         free(ic);
  47 }
  48
  49 static void add_id(struct idcache *ic, char *name, unsigned long int id)
  50 {
  51         struct identry *ent, *x;
  52         int w = 0;
  53
  54         ent = calloc(1, sizeof(struct identry));
  55         if (!ent)
  56                 return;
  57         ent->id = id;
  58
  59         if (name) {
  60 #ifdef HAVE_WIDECHAR
  61                 wchar_t wc[LOGIN_NAME_MAX + 1];
  62
  63                 if (mbstowcs(wc, name, LOGIN_NAME_MAX) > 0) {
  64                         wc[LOGIN_NAME_MAX] = '\0';
  65                         w = wcswidth(wc, LOGIN_NAME_MAX);
  66                 }
  67                 else
  68 #endif
  69                         w = strlen(name);
  70         }
  71
  72         /* note, we ignore names with non-printable widechars */
  73         if (w > 0) {
  74                 ent->name = strdup(name);
  75                 if (!ent->name) {
  76                         free(ent);
  77                         return;
  78                 }
  79         } else {
  80                 if (asprintf(&ent->name, "%lu", id) < 0) {
  81                         free(ent);
  82                         return;
  83                 }
  84         }
  85
  86         for (x = ic->ent; x && x->next; x = x->next);
  87
  88         if (x)
  89                 x->next = ent;
  90         else
  91                 ic->ent = ent;
  92
  93         if (w <= 0)
  94                 w = ent->name ? strlen(ent->name) : 0;
  95         ic->width = ic->width < w ? w : ic->width;
  96         return;
  97 }
  98
  99 void add_uid(struct idcache *cache, unsigned long int id)
 100 {
 101         struct identry *ent= get_id(cache, id);
 102
 103         if (!ent) {
 104                 struct passwd *pw = getpwuid((uid_t) id);
 105                 add_id(cache, pw ? pw->pw_name : NULL, id);
 106         }
 107 }
 108
 109 void add_gid(struct idcache *cache, unsigned long int id)
 110 {
 111         struct identry *ent = get_id(cache, id);
 112
 113         if (!ent) {
 114                 struct group *gr = getgrgid((gid_t) id);
 115                 add_id(cache, gr ? gr->gr_name : NULL, id);
 116         }
 117 }
 118