On 07/31/2012 05:43 PM, Jakub Filak wrote:
> * the old implementation checks only presence of the time file
> * now we check validity of the time file
>
> Signed-off-by: Jakub Filak <[email protected]>
> ---
> src/lib/dump_dir.c | 57
> +++++++++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 54 insertions(+), 3 deletions(-)
>
> diff --git a/src/lib/dump_dir.c b/src/lib/dump_dir.c
> index eef01f7..e945bad 100644
> --- a/src/lib/dump_dir.c
> +++ b/src/lib/dump_dir.c
> @@ -109,6 +109,57 @@ static bool exist_file_dir(const char *path)
> return false;
> }
>
> +static bool not_valid_time_file(const char *filename)
> +{
> + /* Open input file, and parse it. */
> + int fd = open(filename, O_RDONLY);
> + if (fd < 0)
> + {
> + VERB1 log("Unable to open '%s': %s.\n", filename, strerror(errno));
The "\n" is added by log functions themselves. I think you need this:
perror_msg("Can't open '%s'", filename);
> + return true;
> + }
> +
> + off_t size = lseek(fd, 0, SEEK_END);
> + if (size == (off_t)-1) /* EOVERFLOW? */
> + {
> + VERB1 log("Unable to seek in '%s': %s.\n", filename,
> strerror(errno));
> + close(fd);
> + return true;
> + }
> +
> + lseek(fd, 0, SEEK_SET); /* No reason to fail. */
> +
> + static const size_t FILE_SIZE_LIMIT = sizeof(time_t) * 3; /* ~ maximal
> number of digits */
> + if (size > FILE_SIZE_LIMIT)
> + {
> + VERB1 log("Input file too big (%lld). Maximum size is %zd.\n",
> + (long long)size, FILE_SIZE_LIMIT);
> + close(fd);
> + return true;
> + }
You do not need to seek. Do read() of sizeof(time_t) * 3 + 2 bytes right away.
If it reads exactly sizeof(time_t) * 3 + 2 bytes, then the file is too big.
> + char *time_str = xmalloc(size + 1);
Use "char buf[sizeof(time_t) * 3 + 2]" instead: faster than xmalloc+free.
> + if (size != read(fd, time_str, size))
> + {
> + VERB1 log("Unable to read from '%s'.\n", filename);
> + close(fd);
> + free(time_str);
> + return true;
> + }
> +
> + /* Just reading, so no need to check the returned value. */
> + close(fd);
Can have just one close() instead of two:
ssize_t rdsz = read(fd, time_str, sizeof(buf));
close(fd);
if (...) ...
> +
> + time_str[size] = '\0';
> +
> + /* range should OK because of file size condition above */
> + const bool invalidity = !isdigit_str(time_str);
> +
> + free(time_str);
> +
> + return invalidity;
> +}
