src/functional/ungetc.c

   1 #include <stdio.h>
   2 #include <string.h>
   3 #include <errno.h>
   4 #include <limits.h>
   5 #include <unistd.h>
   6 #include "test.h"
   7
   8 #define TEST(r, f, x, m) ( \
   9         errno = 0, ((r) = (f)) == (x) || \
  10         (t_error("%s failed (" m ")\n", #f, r, x, strerror(errno)), 0) )
  11
  12 #define TEST_S(s, x, m) ( \
  13         !strcmp((s),(x)) || \
  14         (t_error("[%s] != [%s] (%s)\n", s, x, m), 0) )
  15
  16 int main(void)
  17 {
  18         int i;
  19         char a[100];
  20         FILE *f;
  21
  22         TEST(i, !(f = tmpfile()), 0, "failed to create temp file %d!=%d (%s)");
  23
  24         if (!f) return t_status;
  25
  26         TEST(i, fprintf(f, "hello, world\n"), 13, "%d != %d (%m)");
  27         TEST(i, fseek(f, 0, SEEK_SET), 0, "%d != %d (%m)");
  28
  29         TEST(i, feof(f), 0, "%d != %d");
  30         TEST(i, fgetc(f), 'h', "'%c' != '%c'");
  31         TEST(i, ftell(f), 1, "%d != %d");
  32         TEST(i, ungetc('x', f), 'x', "%d != %d");
  33         TEST(i, ftell(f), 0, "%d != %d");
  34         TEST(i, fscanf(f, "%[h]", a), 0, "got %d fields, expected %d");
  35         TEST(i, ftell(f), 0, "%d != %d");
  36         TEST(i, fgetc(f), 'x', "'%c' != '%c'");
  37         TEST(i, ftell(f), 1, "%d != %d");
  38
  39         TEST(i, fseek(f, 0, SEEK_SET), 0, "%d != %d");
  40         TEST(i, ungetc('x', f), 'x', "%d != %d");
  41         TEST(i, fread(a, 1, sizeof a, f), 14, "read %d, expected %d");
  42         a[14] = 0;
  43         TEST_S(a, "xhello, world\n", "mismatch reading ungot character");
  44
  45         TEST(i, fseek(f, 0, SEEK_SET), 0, "%d != %d");
  46         TEST(i, fscanf(f, "%[x]", a), 0, "got %d fields, expected %d");
  47         TEST(i, ungetc('x', f), 'x', "unget failed after fscanf: %d != %d");
  48         TEST(i, fgetc(f), 'x', "'%c' != '%c'");
  49         TEST(i, fgetc(f), 'h', "'%c' != '%c'");
  50
  51         fclose(f);
  52         return t_status;
  53 }