gdb print设置技巧，离线查看复杂结构体和数组变量内容，展开多层嵌套的结构体的方法
1. gdb模式下，可以用help set print查看常见的命令
List of set print subcommands:set print address -- Set printing of addresses.
set print array -- Set pretty formatting of arrays.
set print array-indexes -- Set printing of array indexes.
set print asm-demangle -- Set demangling of C++/ObjC names in disassembly listings.
set print demangle -- Set demangling of encoded C++/ObjC names when displaying symbols.
set print elements -- Set limit on string chars or array elements to print.
set print entry-values -- Set printing of function arguments at function entry.
set print finish -- Set whether `finish' prints the return value.
set print frame-arguments -- Set printing of non-scalar frame arguments.
set print frame-info -- Set printing of frame information.
set print inferior-events -- Set printing of inferior events (such as inferior start and exit).
set print max-depth -- Set maximum print depth for nested structures, unions and arrays.
set print max-symbolic-offset -- Set the largest offset that will be printed in <SYMBOL+1234> form.
set print null-stop -- Set printing of char arrays to stop at first null char.
set print object -- Set printing of C++ virtual function tables.
set print pascal_static-members -- Set printing of pascal static members.
set print pretty -- Set pretty formatting of structures.
set print raw-frame-arguments -- Set whether to print frame arguments in raw form.
set print raw-values -- Set whether to print values in raw form.
set print repeats -- Set threshold for repeated print elements.
set print sevenbit-strings -- Set printing of 8-bit characters in strings as \nnn.
set print static-members -- Set printing of C++ static members.
set print symbol -- Set printing of symbol names when printing pointers.
set print symbol-filename -- Set printing of source filename and line number with <SYMBOL>.
set print symbol-loading -- Set printing of symbol loading messages.
set print thread-events -- Set printing of thread events (such as thread start and exit).
set print type -- Generic command for setting how types print.
set print union -- Set printing of unions interior to structures.
set print vtbl -- Set printing of C++ virtual function tables.
2. 常用的设置
# 美化打印，便于阅读
set pagination off /*显示长的内容，不要打断*/
set print pretty on /*结构体漂亮显示*/
set print array on /*数组按列的方式显示*/
set print array-indexes on /*数组加上下标
set print max-depth 4 /*设置结构体的最大打印深度*/
3. 不需要板子，不需要烧录。只要有elf文件，就可以用gdb来进行代码分析。非常的强大方便。
案例1：用gdb打印usb配置描述符的内容
cherryusb的uac/uvc配置描述符，用宏定义了，嵌套了多层宏，非常难以展开，看出其真实的内容是什么。
常用的方法是让代码运行，然后用printf的方法来查看。
其实不用这样，更简单的方式，是直接用arm-none-eabi-gdb对elf文件进行调试，直接print这个结构体变量（全局变量）。
首先用gdb调试elf文件
arm-none-eabi-gdb rt-thread.elf
cherryusb的video_static_mjpeg_template.c例子中的这么一个复杂的配置描述符
static const uint8_t config_descriptor[] = {USB_CONFIG_DESCRIPTOR_INIT(USB_VIDEO_DESC_SIZ, 0x02, 0x01, USB_CONFIG_BUS_POWERED, USBD_MAX_POWER),//VIDEO_VC_DESCRIPTOR_INIT(0x00, VIDEO_INT_EP, 0x0100, VIDEO_VC_TERMINAL_LEN, 48000000, 0x02),VIDEO_VC_NOEP_DESCRIPTOR_INIT(0x00, VIDEO_INT_EP, 0x0100, VIDEO_VC_TERMINAL_LEN, 48000000, 0x02),VIDEO_VS_DESCRIPTOR_INIT(0x01, 0x00, 0x00),VIDEO_VS_INPUT_HEADER_DESCRIPTOR_INIT(0x01, VS_HEADER_SIZ, VIDEO_IN_EP, 0x00),VIDEO_VS_FORMAT_MJPEG_DESCRIPTOR_INIT(0x01, 0x01),VIDEO_VS_FRAME_MJPEG_DESCRIPTOR_INIT(0x01, WIDTH, HEIGHT, MIN_BIT_RATE, MAX_BIT_RATE, MAX_FRAME_SIZE, DBVAL(INTERVAL), 0x01, DBVAL(INTERVAL)),VIDEO_VS_DESCRIPTOR_INIT(0x01, 0x01, 0x01),/* 1.2.2.2 Standard VideoStream Isochronous Video Data Endpoint Descriptor */USB_ENDPOINT_DESCRIPTOR_INIT(VIDEO_IN_EP, 0x05, VIDEO_PACKET_SIZE, 0x01)
};
在gdb中打印config_descriptor，如果不做print格式设置，打印效果如下
(gdb) p/x config_descriptor
$1 = {0x9, 0x2, 0x9e, 0x0, 0x2, 0x1, 0x0, 0x80, 0x32, 0x8, 0xb, 0x0, 0x2, 0xe, 0x3, 0x0, 0x0, 0x9, 0x4, 0x0, 0x0, 0x0, 0xe, 0x1, 0x0, 0x2, 0xd, 0x24, 0x1, 0x0, 0x1, 0x34, 0x0, 0x0, 0x6c,0xdc, 0x2, 0x1, 0x1, 0x12, 0x24, 0x2, 0x1, 0x1, 0x2, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x3, 0x0, 0x0, 0x0, 0xc, 0x24, 0x5, 0x2, 0x1, 0x0, 0x0, 0x2, 0x0, 0x0, 0x0, 0x0, 0x9, 0x24,0x3, 0x3, 0x1, 0x1, 0x0, 0x2, 0x0, 0x9, 0x4, 0x1, 0x0, 0x0, 0xe, 0x2, 0x0, 0x0, 0xe, 0x24, 0x1, 0x1, 0x37, 0x0, 0x81, 0x0, 0x3, 0x0, 0x0, 0x0, 0x1, 0x0, 0xb, 0x24, 0x6, 0x1, 0x1, 0x0,0x1, 0x0, 0x0, 0x0, 0x0, 0x1e, 0x24, 0x7, 0x1, 0x0, 0x80, 0x2, 0xe0, 0x1, 0x0, 0x0, 0xca, 0x8, 0x0, 0x0, 0xca, 0x8, 0x0, 0x60, 0x9, 0x0, 0x15, 0x16, 0x5, 0x0, 0x1, 0x15, 0x16, 0x5, 0x0,0x9, 0x4, 0x1, 0x1, 0x1, 0xe, 0x2, 0x0, 0x0, 0x7, 0x5, 0x81, 0x5, 0xfc, 0x3, 0x1}
输入如下设置，主要针对array数组的显示：
set pagination off /*显示长的内容，不要打断*/
set print array on /*数组按列的方式显示*/
set print array-indexes on /*数组加上下标
做了以上print设置后， 在gdb中打印config_descriptor，效果如下：
(gdb) p/x config_descriptor
$22 = { [0x0] = 0x9, [0x1] = 0x2, [0x2] = 0x9e, [0x3] = 0x0, [0x4] = 0x2, [0x5] = 0x1, [0x6] = 0x0, [0x7] = 0x80, [0x8] = 0x32, [0x9] = 0x8, [0xa] = 0xb, [0xb] = 0x0, [0xc] = 0x2, [0xd] = 0xe, [0xe] = 0x3, [0xf] = 0x0, [0x10] = 0x0, [0x11] = 0x9, [0x12] = 0x4, [0x13] = 0x0, [0x14] = 0x0, [0x15] = 0x0, [0x16] = 0xe, [0x17] = 0x1, [0x18] = 0x0, [0x19] = 0x2, [0x1a] = 0xd, [0x1b] = 0x24, [0x1c] = 0x1, [0x1d] = 0x0, [0x1e] = 0x1, [0x1f] = 0x34, [0x20] = 0x0, [0x21] = 0x0, [0x22] = 0x6c, [0x23] = 0xdc, [0x24] = 0x2, [0x25] = 0x1, [0x26] = 0x1, [0x27] = 0x12, [0x28] = 0x24, [0x29] = 0x2, [0x2a] = 0x1, [0x2b] = 0x1, [0x2c] = 0x2, [0x2d] = 0x0, [0x2e] = 0x0, [0x2f] = 0x0, [0x30] = 0x0, [0x31] = 0x0, [0x32] = 0x0, [0x33] = 0x0, [0x34] = 0x0, [0x35] = 0x3, [0x36] = 0x0, [0x37] = 0x0, [0x38] = 0x0, [0x39] = 0xc, [0x3a] = 0x24, [0x3b] = 0x5, [0x3c] = 0x2, [0x3d] = 0x1, [0x3e] = 0x0, [0x3f] = 0x0, [0x40] = 0x2, [0x41] = 0x0, [0x42] = 0x0, [0x43] = 0x0, [0x44] = 0x0, [0x45] = 0x9, [0x46] = 0x24, [0x47] = 0x3, [0x48] = 0x3, [0x49] = 0x1, [0x4a] = 0x1, [0x4b] = 0x0, [0x4c] = 0x2, [0x4d] = 0x0, [0x4e] = 0x9, [0x4f] = 0x4, [0x50] = 0x1, [0x51] = 0x0, [0x52] = 0x0, [0x53] = 0xe, [0x54] = 0x2, [0x55] = 0x0, [0x56] = 0x0, [0x57] = 0xe, [0x58] = 0x24, [0x59] = 0x1, [0x5a] = 0x1, [0x5b] = 0x37, [0x5c] = 0x0, [0x5d] = 0x81, [0x5e] = 0x0, [0x5f] = 0x3, [0x60] = 0x0, [0x61] = 0x0, [0x62] = 0x0, [0x63] = 0x1, [0x64] = 0x0, [0x65] = 0xb, [0x66] = 0x24, [0x67] = 0x6, [0x68] = 0x1, [0x69] = 0x1, [0x6a] = 0x0, [0x6b] = 0x1, [0x6c] = 0x0, [0x6d] = 0x0, [0x6e] = 0x0, [0x6f] = 0x0, [0x70] = 0x1e, [0x71] = 0x24, [0x72] = 0x7, [0x73] = 0x1, [0x74] = 0x0, [0x75] = 0x80, [0x76] = 0x2, [0x77] = 0xe0, [0x78] = 0x1, [0x79] = 0x0, [0x7a] = 0x0, [0x7b] = 0xca, [0x7c] = 0x8, [0x7d] = 0x0, [0x7e] = 0x0, [0x7f] = 0xca, [0x80] = 0x8, [0x81] = 0x0, [0x82] = 0x60, [0x83] = 0x9, [0x84] = 0x0, [0x85] = 0x15, [0x86] = 0x16, [0x87] = 0x5, [0x88] = 0x0, [0x89] = 0x1, [0x8a] = 0x15, [0x8b] = 0x16, [0x8c] = 0x5, [0x8d] = 0x0, [0x8e] = 0x9, [0x8f] = 0x4, [0x90] = 0x1, [0x91] = 0x1, [0x92] = 0x1, [0x93] = 0xe, [0x94] = 0x2, [0x95] = 0x0, [0x96] = 0x0, [0x97] = 0x7, [0x98] = 0x5, [0x99] = 0x81, [0x9a] = 0x5, [0x9b] = 0xfc, [0x9c] = 0x3, [0x9d] = 0x1
}
(gdb)
案例2：用gdb打印复杂结构体，从而完全展开结构体
cherryusb中存在许多非常复杂，嵌套层次非常深的结构体。比如usbh_core中的struct usbh_bus嵌套层次高达9层，很容易把人绕晕。通过gdb打印复杂结构体，可以完全展开结构体，从而清晰的看到结构体的嵌套层次关系。
首先针对结构体进行设置：
set pagination off /*显示长的内容，不要打断*/
set print pretty on /*结构体漂亮显示*/
set print max-depth 4 /*设置结构体的最大打印深度*/
其次通过i variables，可以显示出各个源文件中的所有的全局变量。比如下面列举了一部分显示结果：
File rt-thread\components\drivers\usb\cherryusb\class\video\usbd_video.c:
36: struct usbd_video_priv g_usbd_video[1];File rt-thread\components\drivers\usb\cherryusb\core\usbd_core.c:
35: const char desc_array[18][64];
116: struct usbd_core_priv g_usbd_core[1];
118: struct usbd_bus g_usbdev_bus[1];File rt-thread\components\drivers\usb\cherryusb\core\usbh_core.c:
20: uint8_t ep0_request_buffer[1][512];
18: usb_slist_t g_bus_head;
21: struct usb_setup_packet g_setup_buffer[1][2][4];
23: struct usbh_bus g_usbhost_bus[1];
15: struct usbh_class_info *usbh_class_info_table_begin;
16: struct usbh_class_info *usbh_class_info_table_end;可以看到，在usbh_core.c中，有一个全局结构体数组变量struct usbh_bus g_usbhost_bus[1]，正是我们需要的。
我们用p/x g_usbhost_bus[0]打印这个结构体。
- 首先设置打印层次为3，效果如下
(gdb) set print max-depth 3
(gdb) p/x g_usbhost_bus[0]
$23 = {list = {next = 0x0},busid = 0x0,hcd = {reg_base = 0x0,hcd_id = 0x0,roothub_intbuf = {[0x0] = 0x0,[0x1] = 0x0},roothub = {connected = 0x0,is_roothub = 0x0,index = 0x0,hub_addr = 0x0,speed = 0x0,nports = 0x0,powerdelay = 0x0,tt_think = 0x0,ismtt = 0x0,hub_desc = {...},hub_ss_desc = {...},child = {...},parent = 0x0,bus = 0x0,intin = 0x0,intin_urb = {...},int_buffer = 0x0,int_timer = 0x0}},devgen = {next = 0x0,alloctab = {[0x0] = 0x0,[0x1] = 0x0,[0x2] = 0x0,[0x3] = 0x0}},hub_thread = 0x0,hub_mq = 0x0
}
- 再设置打印层次为4，效果如下
(gdb) set print max-depth 4
(gdb) p/x g_usbhost_bus[0]
$24 = { list = { next = 0x0 }, busid = 0x0, hcd = { reg_base = 0x0, hcd_id = 0x0, roothub_intbuf = { [0x0] = 0x0, [0x1] = 0x0 }, roothub = { connected = 0x0, is_roothub = 0x0, index = 0x0, hub_addr = 0x0, speed = 0x0, nports = 0x0, powerdelay = 0x0, tt_think = 0x0, ismtt = 0x0, hub_desc = { bLength = 0x0, bDescriptorType = 0x0, bNbrPorts = 0x0, wHubCharacteristics = 0x0, bPwrOn2PwrGood = 0x0, bHubContrCurrent = 0x0, DeviceRemovable = 0x0, PortPwrCtrlMask = 0x0 }, hub_ss_desc = { bLength = 0x0, bDescriptorType = 0x0, bNbrPorts = 0x0, wHubCharacteristics = 0x0, bPwrOn2PwrGood = 0x0, bHubContrCurrent = 0x0, bHubHdrDecLat = 0x0, wHubDelay = 0x0, DeviceRemovable = 0x0 }, child = { [0x0] = {...}, [0x1] = {...}, [0x2] = {...}, [0x3] = {...} }, parent = 0x0, bus = 0x0, intin = 0x0, intin_urb = { list = {...}, hcpriv = 0x0, hport = 0x0, ep = 0x0, data_toggle = 0x0, interval = 0x0, setup = 0x0, transfer_buffer = 0x0, transfer_buffer_length = 0x0, transfer_flags = 0x0, actual_length = 0x0, timeout = 0x0, errorcode = 0x0, num_of_iso_packets = 0x0, start_frame = 0x0, complete = 0x0, arg = 0x0, iso_packet = {...} }, int_buffer = 0x0, int_timer = 0x0 } }, devgen = { next = 0x0, alloctab = { [0x0] = 0x0, [0x1] = 0x0, [0x2] = 0x0, [0x3] = 0x0 } }, hub_thread = 0x0, hub_mq = 0x0
}
- 再设置打印层次为5，效果如下
(gdb) set print max-depth 5
(gdb) p/x g_usbhost_bus[0]
$25 = { list = { next = 0x0 }, busid = 0x0, hcd = { reg_base = 0x0, hcd_id = 0x0, roothub_intbuf = { [0x0] = 0x0, [0x1] = 0x0 }, roothub = { connected = 0x0, is_roothub = 0x0, index = 0x0, hub_addr = 0x0, speed = 0x0, nports = 0x0, powerdelay = 0x0, tt_think = 0x0, ismtt = 0x0, hub_desc = { bLength = 0x0, bDescriptorType = 0x0, bNbrPorts = 0x0, wHubCharacteristics = 0x0, bPwrOn2PwrGood = 0x0, bHubContrCurrent = 0x0, DeviceRemovable = 0x0, PortPwrCtrlMask = 0x0 }, hub_ss_desc = { bLength = 0x0, bDescriptorType = 0x0, bNbrPorts = 0x0, wHubCharacteristics = 0x0, bPwrOn2PwrGood = 0x0, bHubContrCurrent = 0x0, bHubHdrDecLat = 0x0, wHubDelay = 0x0, DeviceRemovable = 0x0 }, child = { [0x0] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = {...}, config = {...}, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = {...}, ep0_urb = {...}, mutex = 0x0 }, [0x1] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = {...}, config = {...}, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = {...}, ep0_urb = {...}, mutex = 0x0 }, [0x2] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = {...}, config = {...}, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = {...}, ep0_urb = {...}, mutex = 0x0 }, [0x3] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = {...}, config = {...}, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = {...}, ep0_urb = {...}, mutex = 0x0 } }, parent = 0x0, bus = 0x0, intin = 0x0, intin_urb = { list = { next = 0x0 }, hcpriv = 0x0, hport = 0x0, ep = 0x0, data_toggle = 0x0, interval = 0x0, setup = 0x0, transfer_buffer = 0x0, transfer_buffer_length = 0x0, transfer_flags = 0x0, actual_length = 0x0, timeout = 0x0, errorcode = 0x0, num_of_iso_packets = 0x0, start_frame = 0x0, complete = 0x0, arg = 0x0, iso_packet = 0x24009ae8 <g_usbhost_bus+11084> }, int_buffer = 0x0, int_timer = 0x0 } }, devgen = { next = 0x0, alloctab = { [0x0] = 0x0, [0x1] = 0x0, [0x2] = 0x0, [0x3] = 0x0 } }, hub_thread = 0x0, hub_mq = 0x0
}
- 再设置打印层次为6，效果如下
(gdb) set print max-depth 6
(gdb) p/x g_usbhost_bus[0]
$26 = { list = { next = 0x0 }, busid = 0x0, hcd = { reg_base = 0x0, hcd_id = 0x0, roothub_intbuf = { [0x0] = 0x0, [0x1] = 0x0 }, roothub = { connected = 0x0, is_roothub = 0x0, index = 0x0, hub_addr = 0x0, speed = 0x0, nports = 0x0, powerdelay = 0x0, tt_think = 0x0, ismtt = 0x0, hub_desc = { bLength = 0x0, bDescriptorType = 0x0, bNbrPorts = 0x0, wHubCharacteristics = 0x0, bPwrOn2PwrGood = 0x0, bHubContrCurrent = 0x0, DeviceRemovable = 0x0, PortPwrCtrlMask = 0x0 }, hub_ss_desc = { bLength = 0x0, bDescriptorType = 0x0, bNbrPorts = 0x0, wHubCharacteristics = 0x0, bPwrOn2PwrGood = 0x0, bHubContrCurrent = 0x0, bHubHdrDecLat = 0x0, wHubDelay = 0x0, DeviceRemovable = 0x0 }, child = { [0x0] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = { bLength = 0x0, bDescriptorType = 0x0, bcdUSB = 0x0, bDeviceClass = 0x0, bDeviceSubClass = 0x0, bDeviceProtocol = 0x0, bMaxPacketSize0 = 0x0, idVendor = 0x0, idProduct = 0x0, bcdDevice = 0x0, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, bNumConfigurations = 0x0 }, config = { config_desc = {...}, intf = {...} }, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = { bLength = 0x0, bDescriptorType = 0x0, bEndpointAddress = 0x0, bmAttributes = 0x0, wMaxPacketSize = 0x0, bInterval = 0x0 }, ep0_urb = { list = {...}, hcpriv = 0x0, hport = 0x0, ep = 0x0, data_toggle = 0x0, interval = 0x0, setup = 0x0, transfer_buffer = 0x0, transfer_buffer_length = 0x0, transfer_flags = 0x0, actual_length = 0x0, timeout = 0x0, errorcode = 0x0, num_of_iso_packets = 0x0, start_frame = 0x0, complete = 0x0, arg = 0x0, iso_packet = {...} }, mutex = 0x0 }, [0x1] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = { bLength = 0x0, bDescriptorType = 0x0, bcdUSB = 0x0, bDeviceClass = 0x0, bDeviceSubClass = 0x0, bDeviceProtocol = 0x0, bMaxPacketSize0 = 0x0, idVendor = 0x0, idProduct = 0x0, bcdDevice = 0x0, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, bNumConfigurations = 0x0 }, config = { config_desc = {...}, intf = {...} }, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = { bLength = 0x0, bDescriptorType = 0x0, bEndpointAddress = 0x0, bmAttributes = 0x0, wMaxPacketSize = 0x0, bInterval = 0x0 }, ep0_urb = { list = {...}, hcpriv = 0x0, hport = 0x0, ep = 0x0, data_toggle = 0x0, interval = 0x0, setup = 0x0, transfer_buffer = 0x0, transfer_buffer_length = 0x0, transfer_flags = 0x0, actual_length = 0x0, timeout = 0x0, errorcode = 0x0, num_of_iso_packets = 0x0, start_frame = 0x0, complete = 0x0, arg = 0x0, iso_packet = {...} }, mutex = 0x0 }, [0x2] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = { bLength = 0x0, bDescriptorType = 0x0, bcdUSB = 0x0, bDeviceClass = 0x0, bDeviceSubClass = 0x0, bDeviceProtocol = 0x0, bMaxPacketSize0 = 0x0, idVendor = 0x0, idProduct = 0x0, bcdDevice = 0x0, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, bNumConfigurations = 0x0 }, config = { config_desc = {...}, intf = {...} }, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = { bLength = 0x0, bDescriptorType = 0x0, bEndpointAddress = 0x0, bmAttributes = 0x0, wMaxPacketSize = 0x0, bInterval = 0x0 }, ep0_urb = { list = {...}, hcpriv = 0x0, hport = 0x0, ep = 0x0, data_toggle = 0x0, interval = 0x0, setup = 0x0, transfer_buffer = 0x0, transfer_buffer_length = 0x0, transfer_flags = 0x0, actual_length = 0x0, timeout = 0x0, errorcode = 0x0, num_of_iso_packets = 0x0, start_frame = 0x0, complete = 0x0, arg = 0x0, iso_packet = {...} }, mutex = 0x0 }, [0x3] = { connected = 0x0, port = 0x0, dev_addr = 0x0, speed = 0x0, depth = 0x0, route = 0x0, slot_id = 0x0, device_desc = { bLength = 0x0, bDescriptorType = 0x0, bcdUSB = 0x0, bDeviceClass = 0x0, bDeviceSubClass = 0x0, bDeviceProtocol = 0x0, bMaxPacketSize0 = 0x0, idVendor = 0x0, idProduct = 0x0, bcdDevice = 0x0, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, bNumConfigurations = 0x0 }, config = { config_desc = {...}, intf = {...} }, iManufacturer = 0x0, iProduct = 0x0, iSerialNumber = 0x0, raw_config_desc = 0x0, setup = 0x0, parent = 0x0, self = 0x0, bus = 0x0, ep0 = { bLength = 0x0, bDescriptorType = 0x0, bEndpointAddress = 0x0, bmAttributes = 0x0, wMaxPacketSize = 0x0, bInterval = 0x0 }, ep0_urb = { list = {...}, hcpriv = 0x0, hport = 0x0, ep = 0x0, data_toggle = 0x0, interval = 0x0, setup = 0x0, transfer_buffer = 0x0, transfer_buffer_length = 0x0, transfer_flags = 0x0, actual_length = 0x0, timeout = 0x0, errorcode = 0x0, num_of_iso_packets = 0x0, start_frame = 0x0, complete = 0x0, arg = 0x0, iso_packet = {...} }, mutex = 0x0 } }, parent = 0x0, bus = 0x0, intin = 0x0, intin_urb = { list = { next = 0x0 }, hcpriv = 0x0, hport = 0x0, ep = 0x0, data_toggle = 0x0, interval = 0x0, setup = 0x0, transfer_buffer = 0x0, transfer_buffer_length = 0x0, transfer_flags = 0x0, actual_length = 0x0, timeout = 0x0, errorcode = 0x0, num_of_iso_packets = 0x0, start_frame = 0x0, complete = 0x0, arg = 0x0, iso_packet = 0x24009ae8 <g_usbhost_bus+11084> }, int_buffer = 0x0, int_timer = 0x0 } }, devgen = { next = 0x0, alloctab = { [0x0] = 0x0, [0x1] = 0x0, [0x2] = 0x0, [0x3] = 0x0 } }, hub_thread = 0x0, hub_mq = 0x0
}