static void
au_stream_rewind(bstreamhandle h)
{
au_filehdr_t au;
(void) lseek(h->bstr_fd, 0L, SEEK_SET);
if (read(h->bstr_fd, &au, sizeof (au)) != sizeof (au)) {
return;
}
if (lseek(h->bstr_fd, (long)(BE32_TO_CPU(au.au_offset)),
SEEK_SET) < 0) {
return;
}
}
void mask_generation(uint8_t *seed, size_t seed_len,
uint8_t *data, size_t data_len)
{
sha1_ctx_t ctx;
uint8_t mask[SHA1_DIGEST_LENGTH];
uint32_t i, len, counter = 0;
while (data_len > 0) {
sha1_init(&ctx);
sha1_update(&ctx, seed, seed_len);
sha1_update(&ctx, (uint8_t*)&counter, 4);
sha1_final(&ctx, mask);
counter = CPU_TO_BE32(BE32_TO_CPU(counter) + 1);
len = (data_len < SHA1_DIGEST_LENGTH) ? data_len : SHA1_DIGEST_LENGTH;
for (i = 0; i < len; i++) *data++ ^= mask[i];
data_len -= len;
}
}
bstreamhandle
open_au_read_stream(char *fname)
{
bstreamhandle h;
int fd, sav;
au_filehdr_t *au;
struct stat st;
uint32_t data_size;
au = NULL;
str_errno = 0;
fd = open(fname, O_RDONLY);
if (fd < 0)
return (NULL);
if (fstat(fd, &st) < 0) {
goto au_open_failed;
}
if ((st.st_mode & S_IFMT) != S_IFREG) {
str_errno = STR_ERR_NO_REG_FILE;
goto au_open_failed;
}
au = (au_filehdr_t *)my_zalloc(sizeof (*au));
if (read(fd, au, sizeof (*au)) != sizeof (*au)) {
str_errno = STR_ERR_AU_READ_ERR;
goto au_open_failed;
}
au->au_magic = BE32_TO_CPU(au->au_magic);
au->au_offset = BE32_TO_CPU(au->au_offset);
au->au_data_size = BE32_TO_CPU(au->au_data_size);
au->au_encoding = BE32_TO_CPU(au->au_encoding);
au->au_sample_rate = BE32_TO_CPU(au->au_sample_rate);
au->au_channels = BE32_TO_CPU(au->au_channels);
if (au->au_magic != AUDIO_AU_FILE_MAGIC) {
str_errno = STR_ERR_AU_BAD_HEADER;
goto au_open_failed;
}
if ((au->au_encoding != AUDIO_AU_ENCODING_LINEAR_16) ||
(au->au_sample_rate != 44100) || (au->au_channels != 2)) {
str_errno = STR_ERR_AU_UNSUPPORTED_FORMAT;
goto au_open_failed;
}
if (au->au_data_size != AUDIO_AU_UNKNOWN_SIZE) {
if ((au->au_offset + au->au_data_size) != st.st_size) {
str_errno = STR_ERR_AU_BAD_HEADER;
goto au_open_failed;
}
data_size = au->au_data_size;
} else {
data_size = st.st_size - au->au_offset;
}
if (data_size == 0) {
str_errno = STR_ERR_AU_UNSUPPORTED_FORMAT;
goto au_open_failed;
}
if (lseek(fd, au->au_offset, SEEK_SET) < 0) {
goto au_open_failed;
}
free(au);
h = (bstreamhandle)my_zalloc(sizeof (*h));
h->bstr_fd = fd;
h->bstr_read = file_stream_read_wrbo;
h->bstr_close = file_stream_close;
h->bstr_size = audio_stream_size;
h->bstr_rewind = au_stream_rewind;
h->bstr_private = (void *)data_size;
return (h);
au_open_failed:
sav = errno;
(void) close(fd);
if (au != NULL)
free(au);
errno = sav;
return (NULL);
}