morgan/UxPlay
1
0
Fork 0
mirror of https://github.com/morgan9e/UxPlay synced 2026-04-14 00:04:13 +09:00
Code Issues Packages Projects Releases Wiki Activity

corrected parsing of DMAP metadata

Browse Source
This commit is contained in:
F. Duncanh
2022-12-13 03:08:24 -05:00
parent 1f8b11033d
commit c3106eb3f5
1 changed files with 60 additions and 38 deletions
Download Patch File Download Diff File Expand all files Collapse all files

98
uxplay.cpp
View File

@@ -21,6 +21,7 @@
#include <cstring>
#include <signal.h>
#include <unistd.h>
#include <ctype.h>
#include <string>
#include <vector>
#include <fstream>
@@ -776,14 +777,13 @@ static void parse_arguments (int argc, char *argv[]) {
}
}
static void process_metadata(int count, const char *dmap_tag, const unsigned char *dmap_len, const char* metadata, int datalen) {
static void process_metadata(int count, const char *dmap_tag, const unsigned char* metadata, int datalen) {
int dmap_type = 0;
/* DMAP metadata items can be strings (dmap_type = 1); other types are byte, short, int, long, date, and list. *
/* DMAP metadata items can be strings (dmap_type = 9); other types are byte, short, int, long, date, and list. *
* The DMAP item begins with a 4-character (4-letter) "dmap_tag" string that identifies the type. */
/* dmap_len is the contents of last byte of 8-byte header preceding metadata, usually equals datalen */
if (debug_log) {
printf("%d: dmap_tag [%s], dmap_len %d %d\n", count, dmap_tag, (int) *dmap_len, datalen);
printf("%d: dmap_tag [%s], %d\n", count, dmap_tag, datalen);
}
/* String-type DMAP tags seen in Apple Music Radio are processed here. *
@@ -794,7 +794,7 @@ static void process_metadata(int count, const char *dmap_tag, const unsigned cha
}
if (dmap_tag[0] == 'a' && dmap_tag[1] == 's') {
dmap_type = 1;
dmap_type = 9;
switch (dmap_tag[2]) {
case 'a':
switch (dmap_tag[3]) {
@@ -869,22 +869,45 @@ static void process_metadata(int count, const char *dmap_tag, const unsigned cha
break;
}
} else if (strcmp (dmap_tag, "minm") == 0) {
dmap_type = 1;
dmap_type = 9;
printf("Title: ");
}
for (int i = 0; i < datalen; i++) {
if (dmap_type == 1) {
printf("%c", metadata[i]);
if (dmap_type == 9) {
printf("%c",(char) metadata[i]);
} else if (debug_log) {
if (i > 0 && i % 16 == 0) printf("\n");
const unsigned char * data = (const unsigned char *) (metadata + i);
printf("%2.2x ", (int) *data);
printf("%2.2x ", (int) metadata[i]);
}
}
printf("\n");
}
static int parse_dmap_header(const unsigned char *metadata, char *tag, int *len) {
const unsigned char *header = metadata;
bool istag = true;
for (int i = 0; i < 4; i++) {
tag[i] = (char) *header;
if (!isalpha(tag[i])) {
istag = false;
}
header++;
}
*len = 0;
for (int i = 0; i < 4; i++) {
*len <<= 8;
*len += (int) *header;
header++;
}
if (!istag || *len < 0) {
return 1;
}
return 0;
}
int main (int argc, char *argv[]) {
std::vector<char> server_hw_addr;
@@ -1172,44 +1195,43 @@ extern "C" void audio_set_coverart(void *cls, const void *buffer, int buflen) {
}
extern "C" void audio_set_metadata(void *cls, const void *buffer, int buflen) {
const unsigned char mark[]={ 0x0, 0x0, 0x0 }; /*daap separator*/
const char *dmap_tag;
const char *metadata = (const char *) buffer;
const unsigned char *dmap_len;
char dmap_tag[5] = {0x0};
const unsigned char *metadata = (const unsigned char *) buffer;
int datalen;
int count = 0;
/* de-concatenate (and process) individual items in DMAP metadata sent by client in AirPlay Audio mode */
/* The metadata packet is a concatenated sequence of DMAP items each consisting of an 8-byte header, usually *
* followed by data. No item is smaller than 8 bytes. The header is a DMAP "tag" of 4 letters, followed by *
* three null bytes and a final byte which is either the byte-length of data that follows, or the data itself. */
if ( buflen < 8 || memcmp (metadata + 4, mark, 3) != 0) {
LOGE("received invalid metadata");
return;
}
printf("==============Audio Metadata=============\n");
if (buflen < 8) {
LOGE("received invalid metadata, length %d < 8", buflen);
return;
} else if (parse_dmap_header(metadata, dmap_tag, &datalen)) {
LOGE("received invalid metadata, tag [%s] datalen %d", dmap_tag, datalen);
return;
}
metadata += 8;
buflen -= 8;
if (strcmp(dmap_tag, "mlit") != 0 || datalen != buflen) {
LOGE("received metadata with tag %s, but is not a DMAP listingitem, or datalen = %d != buflen %d",
dmap_tag, datalen, buflen);
return;
}
while (buflen >= 8) {
dmap_tag = metadata;
if (strlen(dmap_tag) != 4) {
LOGE("received metadata with invalid DMAP tag [%s]", dmap_tag);
break;
}
count++;
dmap_len = (const unsigned char *) (metadata + 7);
if (parse_dmap_header(metadata, dmap_tag, &datalen)) {
LOGE("received metadata with invalid DMAP header: tag = [%s], datalen = %d", dmap_tag, datalen);
return;
}
metadata += 8;
buflen -= 8;
datalen = 0;
while (datalen < buflen && (datalen + 8 > buflen || memcmp(metadata + datalen + 4, mark, 3) != 0)) {
datalen++;
}
process_metadata (count, dmap_tag, dmap_len, metadata, datalen);
buflen -= 8;
process_metadata(count, (const char *) dmap_tag, metadata, datalen);
metadata += datalen;
buflen -= datalen;
}
if (buflen != 0) {
LOGE("%d bytes of metadata were not processed", buflen);
}
}
extern "C" void log_callback (void *cls, int level, const char *msg) {