62 lines
1.2 KiB
C
62 lines
1.2 KiB
C
/* Test program for ungetc/ftell interaction bug. */
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#include <stdio.h>
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static void do_prepare (void);
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#define PREPARE(argc, argv) do_prepare ()
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static int do_test (void);
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#define TEST_FUNCTION do_test ()
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#include <test-skeleton.c>
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static const char pattern[] = "12345";
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static char *temp_file;
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static void
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do_prepare (void)
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{
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int fd = create_temp_file ("bug-ungetc.", &temp_file);
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if (fd == -1)
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{
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printf ("cannot create temporary file: %m\n");
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exit (1);
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}
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write (fd, pattern, sizeof (pattern));
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close (fd);
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}
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static int
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do_test (void)
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{
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int i;
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FILE *f;
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char buf[10];
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long offset, diff;
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int result = 0;
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f = fopen (temp_file, "rw");
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rewind (f);
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for (i = 0; i < 3; i++)
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printf ("%c\n", getc (f));
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offset = ftell (f);
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printf ("offset = %ld\n", offset);
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if (ungetc ('4', f) != '4')
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{
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printf ("ungetc failed\n");
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abort ();
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}
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printf ("offset after ungetc = %ld\n", ftell (f));
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i = fread ((void *) buf, 4, (size_t) 1, f);
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printf ("read %d (%c), offset = %ld\n", i, buf[0], ftell (f));
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diff = ftell (f) - offset;
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if (diff != 3)
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{
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printf ("ftell did not update properly. got %ld, expected 3\n", diff);
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result = 1;
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}
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fclose (f);
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return result;
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}
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