diff options
Diffstat (limited to 'libio/tst-ftell-active-handler.c')
| -rw-r--r-- | libio/tst-ftell-active-handler.c | 112 |
1 files changed, 108 insertions, 4 deletions
diff --git a/libio/tst-ftell-active-handler.c b/libio/tst-ftell-active-handler.c index 5d5fc26547..40ca58c9e2 100644 --- a/libio/tst-ftell-active-handler.c +++ b/libio/tst-ftell-active-handler.c @@ -88,6 +88,107 @@ static size_t file_len; typedef int (*fputs_func_t) (const void *data, FILE *fp); fputs_func_t fputs_func; +/* Test that ftell output after a rewind is correct. */ +static int +do_rewind_test (const char *filename) +{ + int ret = 0; + struct test + { + const char *mode; + int fd_mode; + size_t old_off; + size_t new_off; + } test_modes[] = { + {"w", O_WRONLY, 0, data_len}, + {"w+", O_RDWR, 0, data_len}, + {"r+", O_RDWR, 0, data_len}, + /* The new offsets for 'a' and 'a+' modes have to factor in the + previous writes since they always append to the end of the + file. */ + {"a", O_WRONLY, 0, 3 * data_len}, + {"a+", O_RDWR, 0, 4 * data_len}, + }; + + /* Empty the file before the test so that our offsets are simple to + calculate. */ + FILE *fp = fopen (filename, "w"); + if (fp == NULL) + { + printf ("Failed to open file for emptying\n"); + return 1; + } + fclose (fp); + + for (int j = 0; j < 2; j++) + { + for (int i = 0; i < sizeof (test_modes) / sizeof (struct test); i++) + { + FILE *fp; + int fd; + int fileret; + + printf ("\trewind: %s (file, \"%s\"): ", j == 0 ? "fdopen" : "fopen", + test_modes[i].mode); + + if (j == 0) + fileret = get_handles_fdopen (filename, fd, fp, + test_modes[i].fd_mode, + test_modes[i].mode); + else + fileret = get_handles_fopen (filename, fd, fp, test_modes[i].mode); + + if (fileret != 0) + return fileret; + + /* Write some content to the file, rewind and ensure that the ftell + output after the rewind is 0. POSIX does not specify what the + behavior is when a file is rewound in 'a' mode, so we retain + current behavior, which is to keep the 0 offset. */ + size_t written = fputs_func (data, fp); + + if (written == EOF) + { + printf ("fputs[1] failed to write data\n"); + ret |= 1; + } + + rewind (fp); + long offset = ftell (fp); + + if (offset != test_modes[i].old_off) + { + printf ("Incorrect old offset. Expected %zu, but got %ld, ", + test_modes[i].old_off, offset); + ret |= 1; + } + else + printf ("old offset = %ld, ", offset); + + written = fputs_func (data, fp); + + if (written == EOF) + { + printf ("fputs[1] failed to write data\n"); + ret |= 1; + } + + /* After this write, the offset in append modes should factor in the + implicit lseek to the end of file. */ + offset = ftell (fp); + if (offset != test_modes[i].new_off) + { + printf ("Incorrect new offset. Expected %zu, but got %ld\n", + test_modes[i].new_off, offset); + ret |= 1; + } + else + printf ("new offset = %ld\n", offset); + } + } + return ret; +} + /* Test that the value of ftell is not cached when the stream handle is not active. */ static int @@ -107,11 +208,13 @@ do_ftell_test (const char *filename) {"w", O_WRONLY, 0, data_len}, {"w+", O_RDWR, 0, data_len}, {"r+", O_RDWR, 0, data_len}, - /* For 'a' and 'a+' modes, the initial file position should be the + /* For the 'a' mode, the initial file position should be the current end of file. After the write, the offset has data_len - added to the old value. */ + added to the old value. For a+ mode however, the initial file + position is the file position of the underlying file descriptor, + since it is initially assumed to be in read mode. */ {"a", O_WRONLY, data_len, 2 * data_len}, - {"a+", O_RDWR, 2 * data_len, 3 * data_len}, + {"a+", O_RDWR, 0, 3 * data_len}, }; for (int j = 0; j < 2; j++) { @@ -157,7 +260,7 @@ do_ftell_test (const char *filename) if (off != test_modes[i].new_off) { printf ("Incorrect new offset. Expected %zu but got %ld\n", - test_modes[i].old_off, off); + test_modes[i].new_off, off); ret |= 1; } else @@ -322,6 +425,7 @@ do_one_test (const char *filename) ret |= do_ftell_test (filename); ret |= do_write_test (filename); ret |= do_append_test (filename); + ret |= do_rewind_test (filename); return ret; } |