/* this will print whatever mp3 song you're listening including the id3 tag
 * written by shudder <shudder@gbg.bg> */


#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <fcntl.h>
#include <unistd.h>

#define PROC "/proc"

void read_id3(char *);

struct {
  char tag[3];
  char title[30];
  char artist[30];
  char album[30];
  char year[4];
  char comment[30];
  unsigned char genre;
} id3;

void read_id3(char *file) {
  int fd;

  if ((fd = open(file, O_RDONLY)) == -1) return;

  lseek(fd, -128, SEEK_END);
  read(fd, &id3, 128);

  printf("You are listening to: %s\n"
	 "Title: %-30.30sArtist: %-30.30s\n"
	 "Album: %-30.30sYear: %-4.4s\n"
	 "Comment: %-28.28sTrack: %d\n",
		file, id3.title, id3.artist, id3.album, id3.year,
		id3.comment, id3.comment[29]);
}

int main(int argc, char *argv[]) {
  int l;
  char buffer[1024];
  DIR *dp, *dp_fd;
  struct dirent *de, *de_fd;
  struct stat s;

  if (!(dp = opendir(PROC))) {
    fprintf(stderr, "%s: unable to open: %s\n", argv[0], PROC);
    return 1;
  }

  while ((de = readdir(dp))) {
    if (!atoi(de->d_name) || getpid() == atoi(de->d_name)) continue;
    sprintf(buffer, "%s/%d/fd", PROC, atoi(de->d_name));
    if (!(dp_fd = opendir(buffer))) continue;
    chdir(buffer);
    while ((de_fd = readdir(dp_fd))) {
      lstat(de_fd->d_name, &s);
      if (S_ISLNK(s.st_mode)) {
	memset(buffer, 0, 1024);
	readlink(de_fd->d_name, buffer, 1024);
	/* check for .mp3 extension */
	if ((l = strlen(buffer)) >= 5 && buffer[l-1] == '3'
	   && tolower(buffer[l-2]) == 'p' && tolower(buffer[l-3]) == 'm'
	   && buffer[l-4] == '.')
	  read_id3(buffer);
      }
    }
    closedir(dp_fd);
  }
  closedir(dp);

  return 0;
}