state.c

alsa-utils-1.0.14编译声卡驱动所需要的一些文件源码

		}
		if (strcmp(fld, "subdevice") == 0) {
			if (snd_config_get_type(n) != SND_CONFIG_TYPE_INTEGER) {
				error("control.%d.%s is invalid", numid, fld);
				return -EINVAL;
			}
			snd_config_get_integer(n, &subdevice);
			continue;
		}
		if (strcmp(fld, "name") == 0) {
			if (snd_config_get_type(n) != SND_CONFIG_TYPE_STRING) {
				error("control.%d.%s is invalid", numid, fld);
				return -EINVAL;
			}
			snd_config_get_string(n, &name);
			continue;
		}
		if (strcmp(fld, "index") == 0) {
			if (snd_config_get_type(n) != SND_CONFIG_TYPE_INTEGER) {
				error("control.%d.%s is invalid", numid, fld);
				return -EINVAL;
			}
			snd_config_get_integer(n, &index);
			continue;
		}
		if (strcmp(fld, "value") == 0) {
			value = n;
			continue;
		}
		error("unknown control.%d.%s field", numid, fld);
	}
	if (!value) {
		error("missing control.%d.value", numid);
		return -EINVAL;
	}
	if (device < 0)
		device = 0;
	if (subdevice < 0)
		subdevice = 0;
	if (index < 0)
		index = 0;

	err = -EINVAL;
	if (! force_restore) {
		snd_ctl_elem_info_set_numid(info, numid);
		err = snd_ctl_elem_info(handle, info);
	}
	if (err < 0) {
		if (iface >= 0 && name) {
			snd_ctl_elem_info_set_numid(info, 0);
			snd_ctl_elem_info_set_interface(info, iface);
			snd_ctl_elem_info_set_device(info, device);
			snd_ctl_elem_info_set_subdevice(info, subdevice);
			snd_ctl_elem_info_set_name(info, name);
			snd_ctl_elem_info_set_index(info, index);
			err = snd_ctl_elem_info(handle, info);
			if (err < 0 && comment && is_user_control(comment)) {
				err = add_user_control(handle, info, comment);
				if (err < 0) {
					error("failed to add user control #%d (%s)",
					      numid, snd_strerror(err));
					return err;
				}
			}
		}
	}
	if (err < 0) {
		error("failed to obtain info for control #%d (%s)", numid, snd_strerror(err));
		return -ENOENT;
	}
	numid1 = snd_ctl_elem_info_get_numid(info);
	iface1 = snd_ctl_elem_info_get_interface(info);
	device1 = snd_ctl_elem_info_get_device(info);
	subdevice1 = snd_ctl_elem_info_get_subdevice(info);
	name1 = snd_ctl_elem_info_get_name(info);
	index1 = snd_ctl_elem_info_get_index(info);
	count = snd_ctl_elem_info_get_count(info);
	type = snd_ctl_elem_info_get_type(info);
	if (err |= numid != numid1 && ! force_restore)
		error("warning: numid mismatch (%d/%d) for control #%d", 
		      numid, numid1, numid);
	if (err |= iface != iface1)
		error("warning: iface mismatch (%d/%d) for control #%d", iface, iface1, numid);
	if (err |= device != device1)
		error("warning: device mismatch (%ld/%ld) for control #%d", device, device1, numid);
	if (err |= subdevice != subdevice1)
		error("warning: subdevice mismatch (%ld/%ld) for control #%d", subdevice, subdevice1, numid);
	if (err |= strcmp(name, name1))
		error("warning: name mismatch (%s/%s) for control #%d", name, name1, numid);
	if (err |= index != index1)
		error("warning: index mismatch (%ld/%ld) for control #%d", index, index1, numid);
	if (err < 0) {
		error("failed to obtain info for control #%d (%s)", numid, snd_strerror(err));
		return -ENOENT;
	}

#if 0
	if (comment) {
		check_comment_type(comment, type);
		if (type == SND_CTL_ELEM_TYPE_INTEGER ||
		    type == SND_CTL_ELEM_TYPE_INTEGER64)
			check_comment_range(comment, info);
	}
#endif

	if (!snd_ctl_elem_info_is_writable(info))
		return 0;
	snd_ctl_elem_value_set_numid(ctl, numid1);

	if (count == 1) {
		switch (type) {
		case SND_CTL_ELEM_TYPE_BOOLEAN:
			val = config_bool(value);
			if (val >= 0) {
				snd_ctl_elem_value_set_boolean(ctl, 0, val);
				goto _ok;
			}
			break;
		case SND_CTL_ELEM_TYPE_INTEGER:
			err = snd_config_get_integer(value, &val);
			if (err == 0) {
				snd_ctl_elem_value_set_integer(ctl, 0, val);
				goto _ok;
			}
			break;
		case SND_CTL_ELEM_TYPE_INTEGER64:
			err = snd_config_get_integer64(value, &lval);
			if (err == 0) {
				snd_ctl_elem_value_set_integer64(ctl, 0, lval);
				goto _ok;
			}
			break;
		case SND_CTL_ELEM_TYPE_ENUMERATED:
			val = config_enumerated(value, handle, info);
			if (val >= 0) {
				snd_ctl_elem_value_set_enumerated(ctl, 0, val);
				goto _ok;
			}
			break;
		case SND_CTL_ELEM_TYPE_BYTES:
		case SND_CTL_ELEM_TYPE_IEC958:
			break;
		default:
			error("Unknow control type: %d", type);
			return -EINVAL;
		}
	}
	switch (type) {
	case SND_CTL_ELEM_TYPE_BYTES:
	case SND_CTL_ELEM_TYPE_IEC958:
	{
		const char *buf;
		err = snd_config_get_string(value, &buf);
		if (err >= 0) {
			int c1 = 0;
			int len = strlen(buf);
			unsigned int idx = 0;
			int size = type == SND_CTL_ELEM_TYPE_BYTES ?
				count : sizeof(snd_aes_iec958_t);
			if (size * 2 != len) {
				error("bad control.%d.value contents\n", numid);
				return -EINVAL;
			}
			while (*buf) {
				int c = *buf++;
				if ((c = hextodigit(c)) < 0) {
					error("bad control.%d.value contents\n", numid);
					return -EINVAL;
				}
				if (idx % 2 == 1)
					snd_ctl_elem_value_set_byte(ctl, idx / 2, c1 << 4 | c);
				else
					c1 = c;
				idx++;
			}
			goto _ok;
		}
	}
	default:
		break;
	}
	if (snd_config_get_type(value) != SND_CONFIG_TYPE_COMPOUND) {
		error("bad control.%d.value type", numid);
		return -EINVAL;
	}

	set = (char*) alloca(count);
	memset(set, 0, count);
	snd_config_for_each(i, next, value) {
		snd_config_t *n = snd_config_iterator_entry(i);
		const char *id;
		if (snd_config_get_id(n, &id) < 0)
			continue;
		idx = atoi(id);
		if (idx < 0 || idx >= count || 
		    set[idx]) {
			error("bad control.%d.value index", numid);
			return -EINVAL;
		}
		switch (type) {
		case SND_CTL_ELEM_TYPE_BOOLEAN:
			val = config_bool(n);
			if (val < 0) {
				error("bad control.%d.value.%d content", numid, idx);
				return -EINVAL;
			}
			snd_ctl_elem_value_set_boolean(ctl, idx, val);
			break;
		case SND_CTL_ELEM_TYPE_INTEGER:
			err = snd_config_get_integer(n, &val);
			if (err < 0) {
				error("bad control.%d.value.%d content", numid, idx);
				return -EINVAL;
			}
			snd_ctl_elem_value_set_integer(ctl, idx, val);
			break;
		case SND_CTL_ELEM_TYPE_INTEGER64:
			err = snd_config_get_integer64(n, &lval);
			if (err < 0) {
				error("bad control.%d.value.%d content", numid, idx);
				return -EINVAL;
			}
			snd_ctl_elem_value_set_integer64(ctl, idx, lval);
			break;
		case SND_CTL_ELEM_TYPE_ENUMERATED:
			val = config_enumerated(n, handle, info);
			if (val < 0) {
				error("bad control.%d.value.%d content", numid, idx);
				return -EINVAL;
			}
			snd_ctl_elem_value_set_enumerated(ctl, idx, val);
			break;
		case SND_CTL_ELEM_TYPE_BYTES:
		case SND_CTL_ELEM_TYPE_IEC958:
			err = snd_config_get_integer(n, &val);
			if (err < 0 || val < 0 || val > 255) {
				error("bad control.%d.value.%d content", numid, idx);
				return -EINVAL;
			}
			snd_ctl_elem_value_set_byte(ctl, idx, val);
			break;
		default:
			break;
		}
		set[idx] = 1;
	}
	for (idx = 0; idx < count; ++idx) {
		if (!set[idx]) {
			error("control.%d.value.%d is not specified", numid, idx);
			return -EINVAL;
		}
	}

 _ok:
	err = snd_ctl_elem_write(handle, ctl);
	if (err < 0) {
		error("Cannot write control '%d:%ld:%ld:%s:%ld' : %s", (int)iface, device, subdevice, name, index, snd_strerror(err));
		return err;
	}
	return 0;
}

static int set_controls(int card, snd_config_t *top)
{
	snd_ctl_t *handle;
	snd_ctl_card_info_t *info;
	snd_config_t *control;
	snd_config_iterator_t i, next;
	int err;
	char name[32], tmpid[16];
	const char *id;
	snd_ctl_card_info_alloca(&info);

	sprintf(name, "hw:%d", card);
	err = snd_ctl_open(&handle, name, 0);
	if (err < 0) {
		error("snd_ctl_open error: %s", snd_strerror(err));
		return err;
	}
	err = snd_ctl_card_info(handle, info);
	if (err < 0) {
		error("snd_ctl_card_info error: %s", snd_strerror(err));
		goto _close;
	}
	id = snd_ctl_card_info_get_id(info);
	err = snd_config_searchv(top, &control, "state", id, "control", 0);
	if (err < 0) {
		if (force_restore) {
			sprintf(tmpid, "card%d", card);
			err = snd_config_searchv(top, &control, "state", tmpid, "control", 0);
			if (! err)
				id = tmpid;
		}
		if (err < 0) {
			fprintf(stderr, "No state is present for card %s\n", id);
			goto _close;
		}
		id = tmpid;
	}
	if (snd_config_get_type(control) != SND_CONFIG_TYPE_COMPOUND) {
		error("state.%s.control is not a compound\n", id);
		return -EINVAL;
	}
	snd_config_for_each(i, next, control) {
		snd_config_t *n = snd_config_iterator_entry(i);
		err = set_control(handle, n);
		if (err < 0 && ! force_restore)
			goto _close;
	}

 _close:
	snd_ctl_close(handle);
	return err;
}

int save_state(const char *file, const char *cardname)
{
	int err;
	snd_config_t *config;
	snd_input_t *in;
	snd_output_t *out;
	int stdio;

	err = snd_config_top(&config);
	if (err < 0) {
		error("snd_config_top error: %s", snd_strerror(err));
		return err;
	}
	stdio = !strcmp(file, "-");
	if (!stdio && (err = snd_input_stdio_open(&in, file, "r")) >= 0) {
		err = snd_config_load(config, in);
		snd_input_close(in);
#if 0
		if (err < 0) {
			error("snd_config_load error: %s", snd_strerror(err));
			return err;
		}
#endif
	}

	if (!cardname) {
		int card, first = 1;

		card = -1;
		/* find each installed soundcards */
		while (1) {
			if (snd_card_next(&card) < 0)
				break;
			if (card < 0) {
				if (first) {
					error("No soundcards found...");
					return -ENODEV;
				}
				break;
			}
			first = 0;
			if ((err = get_controls(card, config)))
				return err;
		}
	} else {
		int cardno;

		cardno = snd_card_get_index(cardname);
		if (cardno < 0) {
			error("Cannot find soundcard '%s'...", cardname);
			return cardno;
		}
		if ((err = get_controls(cardno, config))) {
			return err;
		}
	}
	
	if (stdio)
		err = snd_output_stdio_attach(&out, stdout, 0);
	else
		err = snd_output_stdio_open(&out, file, "w");
	if (err < 0) {
		error("Cannot open %s for writing: %s", file, snd_strerror(err));
		return -errno;
	}
	err = snd_config_save(config, out);
	snd_output_close(out);
	if (err < 0)
		error("snd_config_save: %s", snd_strerror(err));
	return 0;
}

int load_state(const char *file, const char *cardname)
{
	int err;
	snd_config_t *config;
	snd_input_t *in;
	int stdio;

	err = snd_config_top(&config);
	if (err < 0) {
		error("snd_config_top error: %s", snd_strerror(err));
		return err;
	}
	stdio = !strcmp(file, "-");
	if (stdio)
		err = snd_input_stdio_attach(&in, stdin, 0);
	else
		err = snd_input_stdio_open(&in, file, "r");
	if (err >= 0) {
		err = snd_config_load(config, in);
		snd_input_close(in);
		if (err < 0) {
			error("snd_config_load error: %s", snd_strerror(err));
			return err;
		}
	} else {
		error("Cannot open %s for reading: %s", file, snd_strerror(err));
		return err;
	}

	if (!cardname) {
		int card, first = 1;

		card = -1;
		/* find each installed soundcards */
		while (1) {
			if (snd_card_next(&card) < 0)
				break;
			if (card < 0) {
				if (first) {
					error("No soundcards found...");
					return -ENODEV;
				}
				break;
			}
			first = 0;
			if ((err = set_controls(card, config)) && ! force_restore)
				return err;
		}
	} else {
		int cardno;

		cardno = snd_card_get_index(cardname);
		if (cardno < 0) {
			error("Cannot find soundcard '%s'...", cardname);
			return -ENODEV;
		}
		if ((err = set_controls(cardno, config)) && ! force_restore) {
			return err;
		}
	}
	return 0;
}