music.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

#include <u.h>
#include <libc.h>
#include <thread.h>
#include <draw.h>
#include <keyboard.h>
#include <mouse.h>
#include <control.h>
#include "colors.h"
#include "client.h"
#include "playlist.h"
#include "../debug.h"

int	debug = 0; //DBGSERVER|DBGPUMP|DBGSTATE|DBGPICKLE|DBGPLAY;

char	usage[] = "Usage: %s [-d mask] [-t] [-w]\n";

typedef struct But {
	char	*name;
	Control	*ctl;
} But;

typedef struct Simpleitem {
	char	*address;
	char	*data;
} Simpleitem;

typedef struct Multiitem {
	char	*address;
	int	ndata;
	char	**data;
} Multiitem;

enum {
	WinBrowse,
	WinPlay,
	WinPlaylist,
	WinError,
	Topselect = 0x7fffffff,

	Browsedepth = 63,
};

typedef enum {
	PlayIdle,
	PlayStart,
	Playing,
	PlayPause,
} Playstate;

typedef enum {
	User,
	Troot,
	Rroot,
	Tchildren,
	Rchildren,
	Tparent,
	Rparent,
	Tinfo,
	Rinfo,
	Tparentage,
	Rparentage,
	Tplay,
	Rplay,
} Srvstate;

enum {
	Exitbutton,
	Pausebutton,
	Playbutton,
	Stopbutton,
	Prevbutton,
	Nextbutton,
	Rootbutton,
	Deletebutton,
	Helpbutton,
	Volume,
	Browsetopwin,
	Browsebotwin,
	Browsebotscr,
	Playevent,
	Playlistwin,
	Nalt,
};

But buts[] = {
	[Exitbutton] =		{"skull", nil},
	[Pausebutton] =		{"pause", nil},
	[Playbutton] =		{"play", nil},
	[Stopbutton] =		{"stop", nil},
	[Prevbutton] =		{"prev", nil},
	[Nextbutton] =		{"next", nil},
	[Rootbutton] =		{"root", nil},
	[Deletebutton] =	{"trash", nil},
	[Helpbutton] =		{"question", nil},
};

struct tab {
	char *tabname;
	char *winname;
	Control *tab;
	Control *win;
} tabs[4] = {
	[WinBrowse] =	{"Browse",	"browsewin",	nil, nil},
	[WinPlay] =	{"Playing",	"playwin",	nil, nil},
	[WinPlaylist] =	{"Playlist",	"listwin",	nil, nil},
	[WinError] =	{"Errors",	"errorwin",	nil, nil},
};

char *helptext[] = {
	"Buttons, left to right:",
	"    Exit: exit jukebox",
	"    Pause: pause/resume playback",
	"    Play: play selection in Playlist",
	"    Stop: stop playback",
	"    Prev: play previous item in Playlist",
	"    Next: play next item in Playlist",
	"    Root: browse to root of database tree",
	"    Delete: empty Playlist, reread database",
	"    Help: show this window",
	"",
	"Browse window: (click tab to bring forward)",
	"  Top window displays current item",
	"  Bottom window displays selectable subitems",
	"  Mouse commands:",
	"    Left: selected subitem becomes current",
	"    Right: parent of current item becomes current",
	"    Middle: add item or subitem to Playlist",
	"",
	"Playing window",
	"  Displays item currently playing",
	"",
	"Playlist window",
	"  Displays contents of Playlist",
	"  Mouse commands:",
	"    Left: select item",
	"    (then click the play button)",
	"",
	"Error window",
	"  Displays error messages received from player",
	"  (e.g., can't open file)",
	nil,
};

struct Browsestack {
	char	*onum;
	int	scrollpos;
} browsestack[Browsedepth];
int browsesp;	/* browse stack pointer */
int browseline;	/* current browse position */

Control		*vol;
Control		*browsetopwin;
Control		*browsebotwin;
Control		*playlistwin;
Control		*errortext;
Control		*browsetopscr;
Control		*browsebotscr;

Playstate	playstate;

ulong		playingbuts = 1<<Pausebutton | 1<<Stopbutton | 1<<Prevbutton | 1<<Nextbutton;
ulong		activebuts;

int		tabht;
Image		*vol1img;
Image		*vol2img;

int		resizeready;
int		borderwidth = 1;
int		butht, butwid;
int		errorlines;

int		tflag;
int		pflag;

Controlset	*cs;

char		*root;
Multiitem	parent;
Simpleitem	children[2048];
int		nchildren;

int		selected;

Channel		*playevent;

void
readbuts(void)
{
	static char str[32], file[64];
	But *b;
	int fd;
	Image *img, *mask;

	for(b = buts; b < &buts[nelem(buts)]; b++){
		sprint(file, "%s/%s.bit", ICONPATH, b->name);
		if((fd = open(file, OREAD)) < 0)
			sysfatal("open: %s: %r", file);
		mask = readimage(display, fd, 0);
		close(fd);
		butwid = Dx(mask->r);
		butht = Dy(mask->r);
		b->ctl = createbutton(cs, b->name);
		chanprint(cs->ctl, "%q align center", b->name);
		chanprint(cs->ctl, "%q border 0", b->name);

		img = allocimage(display, mask->r, screen->chan, 0, 0xe0e0ffff);
		draw(img, img->r, darkgreen, mask, mask->r.min);
		sprint(str, "%s.active", b->name);
		namectlimage(img, str);

		img = allocimage(display, mask->r, screen->chan, 0, 0xe0e0ffff);
		draw(img, img->r, lightblue, mask, mask->r.min);
		sprint(str, "%s.passive", b->name);
		namectlimage(img, str);

		chanprint(cs->ctl, "%q image %q", b->name, str);
		sprint(str, "%s.mask", b->name);
		namectlimage(mask, str);
		chanprint(cs->ctl, "%q mask %q", b->name, str);
		chanprint(cs->ctl, "%q light red", b->name);
		chanprint(cs->ctl, "%q size %d %d %d %d", b->name, butwid, butht, butwid, butht);
	}
}

void
activatebuttons(ulong mask)
{	// mask bit i corresponds to buts[i];
	ulong bit;
	But *b;
	static char str[40];
	int i;

	for(i = 0; i < nelem(buts); i++){
		b = &buts[i];
		bit = 1 << i;
		if((mask & bit) && (activebuts & bit) == 0){
			// button was `deactive'
			activate(b->ctl);
			activebuts |= bit;
			sprint(str, "%s.active", b->name);
			chanprint(cs->ctl, "%q image %q", b->name, str);
			chanprint(cs->ctl, "%q show", b->name);
		}
	}
}

void
deactivatebuttons(ulong mask)
{	// mask bit i corresponds with buts[i];
	ulong bit;
	But *b;
	static char str[40];
	int i;

	for(i = 0; i < nelem(buts); i++){
		b = &buts[i];
		bit = 1 << i;
		if((mask & bit) && (activebuts & bit)){
			// button was active
			deactivate(b->ctl);
			activebuts &= ~bit;
			sprint(str, "%s.passive", b->name);
			chanprint(cs->ctl, "%q image %q", b->name, str);
			chanprint(cs->ctl, "%q show", b->name);
		}
	}
}

void
resizecontrolset(Controlset *){
	static Point pol[3];
	char *p;

	if(getwindow(display, Refbackup) < 0)
		sysfatal("getwindow");
	draw(screen, screen->r, bordercolor, nil, screen->r.min);
	if(!resizeready)
		return;
#ifndef REPLACESEMANTICS
	if(vol1img)
		chanprint(cs->ctl, "volume image darkgreen");
	if(vol2img)
		chanprint(cs->ctl, "volume indicatorcolor red");
	chanprint(cs->ctl, "wholewin size");
	chanprint(cs->ctl, "wholewin rect %R", screen->r);

	chanprint(cs->ctl, "sync");
	p = recvp(cs->data);
	if(strcmp(p, "sync"))
		sysfatal("huh?");
	free(p);

	if(vol1img){
		freectlimage("volume.img");
		freeimage(vol1img);
	}
	if(vol2img){
		freectlimage("indicator.img");
		freeimage(vol2img);
	}
	vol1img = allocimage(display, vol->rect, screen->chan, 0, 0xe0e0ffff);
	vol2img = allocimage(display, vol->rect, screen->chan, 0, 0xe0e0ffff);
	pol[0] = Pt(vol->rect.min.x, vol->rect.max.y);
	pol[1] = Pt(vol->rect.max.x, vol->rect.min.y);
	pol[2] = vol->rect.max;
	fillpoly(vol1img, pol, 3, 0, darkgreen, ZP);
	fillpoly(vol2img, pol, 3, 0, red, ZP);
	namectlimage(vol1img, "volume.img");
	namectlimage(vol2img, "indicator.img");
	chanprint(cs->ctl, "volume image volume.img");
	chanprint(cs->ctl, "volume indicatorcolor indicator.img");
#else
	chanprint(cs->ctl, "wholewin size");
	chanprint(cs->ctl, "wholewin rect %R", screen->r);

	chanprint(cs->ctl, "sync");
	p = recvp(cs->data);
	if(strcmp(p, "sync"))
		sysfatal("huh?");
	free(p);

	new1img = allocimage(display, vol->rect, screen->chan, 0, 0xe0e0ffff);
	new2img = allocimage(display, vol->rect, screen->chan, 0, 0xe0e0ffff);
	pol[0] = Pt(vol->rect.min.x, vol->rect.max.y);
	pol[1] = Pt(vol->rect.max.x, vol->rect.min.y);
	pol[2] = vol->rect.max;
	fillpoly(new1img, pol, 3, 0, darkgreen, ZP);
	fillpoly(new2img, pol, 3, 0, red, ZP);
	namectlimage(new1img, "volume.img");
	namectlimage(new2img, "indicator.img");
	if(vol1img)
		freeimage(vol1img);
	else
		chanprint(cs->ctl, "volume image volume.img");
	if(vol2img)
		freeimage(vol2img);
	else
		chanprint(cs->ctl, "volume indicatorcolor indicator.img");
	vol1img = new1img;
	vol2img = new2img;
#endif
	chanprint(cs->ctl, "browsetopscr vis '%d'",
		Dy(controlcalled("browsetopscr")->rect)/romanfont->height);
	chanprint(cs->ctl, "browsebotscr vis '%d'",
		Dy(controlcalled("browsebotscr")->rect)/romanfont->height);
	chanprint(cs->ctl, "playscr vis '%d'",
		Dy(controlcalled("playscr")->rect)/romanfont->height);
	chanprint(cs->ctl, "playlistscr vis '%d'",
		Dy(controlcalled("playlistscr")->rect)/romanfont->height);
	chanprint(cs->ctl, "wholewin show");
}

void
maketab(void)
{
	int i;

	tabht = boldfont->height + 1 + borderwidth;

	createtab(cs, "tabs");

	for(i = 0; i < nelem(tabs); i++){
		tabs[i].tab = createtextbutton(cs, tabs[i].tabname);