fs.c

   1 // Copyright (2013) Jann Horn <jann@thejh.net>
   2
   3 HEADER #include <stdio.h>
   4 HEADER #include <sys/types.h>
   5 HEADER #include <dirent.h>
   6
   7 #include <errno.h>
   8
   9 // nonzero iterator exit code means cancel
  10 HEADER typedef int dir_iterator(struct dirent *dent, void *data);
  11 PUBLIC_FN int fdir_foreach(DIR *d, dir_iterator *iter, void *data) {
  12   struct dirent de;
  13   struct dirent *res;
  14   while (1) {
  15     int rd_res = readdir_r(d, &de, &res);
  16     if (rd_res) return rd_res;
  17     if (res == NULL) return 0;
  18     int iter_res = iter(&de, data);
  19     if (iter_res) return iter_res;
  20   }
  21 }
  22
  23 PUBLIC_FN int dir_foreach(char *path, dir_iterator *iter, void *data) {
  24   DIR *d = opendir(path);
  25   if (d == NULL) return 1;
  26   int feach_res = fdir_foreach(d, iter, data);
  27   int errno_ = errno;
  28   closedir(d);
  29   errno = errno_;
  30   return feach_res;
  31 }
  32
  33 PUBLIC_FN int mkdir_maybe(const char *path, mode_t mode) {
  34   int r = mkdir(path, mode);
  35   if (r && errno != EEXIST) {
  36     return r;
  37   }
  38   return 0;
  39 }
  40
  41 HEADER // requires stdio.h
  42 HEADER #define FDIR_FOREACH(dir, element_name, code) {                                                     \
  43 HEADER   struct dirent element_name;                                                                       \
  44 HEADER   struct dirent *__jh_fdir_foreach_res;                                                             \
  45 HEADER   while (1) {                                                                                       \
  46 HEADER     int __jh_fdir_foreach_rd_res = readdir_r(dir, &element_name, &__jh_fdir_foreach_res);           \
  47 HEADER     if(__jh_fdir_foreach_rd_res) {*(char*)0 = 0; /*crash, boom – EBADF happened (probably)*/}       \
  48 HEADER     if (__jh_fdir_foreach_res == NULL) goto end;                                                    \
  49 HEADER     {code}                                                                                          \
  50 HEADER   }                                                                                                 \
  51 HEADER   end:;                                                                                             \
  52 HEADER }