/* Generate a temporary file containing sort-of random data. Diffs
between files of random data tend to be pretty boring, so we try to
make sure there are a bunch of common substrings between two runs
of this function with the same seedbase. */
static apr_file_t *
generate_random_file(apr_uint32_t maxlen,
apr_uint32_t subseed_base,
apr_uint32_t *seed,
const char *random_bytes,
apr_size_t bytes_range,
int dump_files,
apr_pool_t *pool)
{
static char file_buffer[10240];
char *buf = file_buffer;
char *const end = buf + sizeof file_buffer;
apr_uint32_t len, seqlen;
apr_file_t *fp;
unsigned long r;
fp = open_tempfile("random_XXXXXX", pool);
len = svn_test_rand(seed) % maxlen; /* We might go over this by a bit. */
while (len > 0)
{
/* Generate a pseudo-random sequence of up to MAXSEQ bytes,
where the seed is in the range [seedbase..seedbase+MAXSEQ-1].
(Use our own pseudo-random number generator here to avoid
clobbering the seed of the libc random number generator.) */
seqlen = svn_test_rand(seed) % MAXSEQ;
if (seqlen > len) seqlen = len;
len -= seqlen;
r = subseed_base + svn_test_rand(seed) % SEEDS;
while (seqlen-- > 0)
{
const int ch = (random_bytes
? (unsigned)random_bytes[r % bytes_range]
: (int)(r % bytes_range));
if (buf == end)
{
apr_size_t ignore_length;
apr_file_write_full(fp, file_buffer, sizeof file_buffer,
&ignore_length);
buf = file_buffer;
}
*buf++ = (char)ch;
r = r * 1103515245 + 12345;
}
}
if (buf > file_buffer)
{
apr_size_t ignore_length;
apr_file_write_full(fp, file_buffer, buf - file_buffer, &ignore_length);
}
rewind_file(fp);
if (dump_files)
dump_file_contents(fp);
return fp;
}
/* Compare two open files. The file positions may change. */
static svn_error_t *
compare_files(apr_file_t *f1, apr_file_t *f2, int dump_files)
{
static char file_buffer_1[10240];
static char file_buffer_2[10240];
char *c1, *c2;
apr_off_t pos = 0;
apr_size_t len1, len2;
rewind_file(f1);
rewind_file(f2);
if (dump_files)
dump_file_contents(f2);
do
{
apr_file_read_full(f1, file_buffer_1, sizeof file_buffer_1, &len1);
apr_file_read_full(f2, file_buffer_2, sizeof file_buffer_2, &len2);
for (c1 = file_buffer_1, c2 = file_buffer_2;
c1 < file_buffer_1 + len1 && c2 < file_buffer_2 + len2;
++c1, ++c2, ++pos)
{
if (*c1 != *c2)
return svn_error_createf(SVN_ERR_TEST_FAILED, NULL,
"mismatch at position %"APR_OFF_T_FMT,
pos);
}
if (len1 != len2)
return svn_error_createf(SVN_ERR_TEST_FAILED, NULL,
"unequal file sizes at position"
" %"APR_OFF_T_FMT, pos);
}
while (len1 == sizeof file_buffer_1);
return SVN_NO_ERROR;
}
