digitalmars.D - Translation of C struct to D
- Michael Kremser (50/50) Nov 14 2011 Hi!
- Jerry (4/49) Nov 14 2011 This looks like you don't have druntime or phobos linked into your
- Michael Kremser (24/28) Nov 15 2011 My Makefile looks as follows:
- Bernard Helyer (1/1) Nov 15 2011 kbuild is almost certainly not linking in phobos.
- Iain Buclaw (16/66) Nov 15 2011 in-d/
- Michael Kremser (9/13) Nov 16 2011 This yields the following compiler error:
- Trass3r (1/4) Nov 16 2011 Or use DEVICE_NAME.ptr
- Michael Kremser (12/17) Nov 17 2011 Compilation now succeeded, but when I try to load with insmod, the
Hi!
I currently try to create a simple linux driver (for test purposes) just
like in [1] in D based on [2]. The main difficulty is to call
register_chrdev. It expects an argument "fops" of type file_operations
which can look like that in C:
static struct file_operations fops = {
.read = device_read,
.write = device_write,
.open = device_open,
.release = device_release
};
device_read and so on are functions. Originally, file_operations has
much more fields and it's possible to omit unused fields.
What I tried so far: I declared "register_chrdev" as follows:
extern (C):
int register_chrdev (uint major, char *name, file_operations *fops);
My try for the translation of file_operations looks like that:
struct file_operations {
int function() open;
int function() release;
};
In init_module() I have the following code:
char[] DEVICE_NAME = "dtestdev";
file_operations fops;
fops.open = &device_open;
fops.release = &device_close;
Major = register_chrdev(0, std.string.toStringz(DEVICE_NAME), &fops);
The code compiles with some warnings, and if I try to insert it into the
kernel, I get some messages in the kernel log.
WARNING: "_D3std6string9toStringzFAaZPa" [...../hello.ko] undefined!
WARNING: "_Dmodule_ref" [...../hello.ko] undefined!
WARNING: "_D15TypeInfo_Struct6__vtblZ" [...../hello.ko] undefined!
WARNING: "register_chrdev" [...../hello.ko] undefined!
WARNING: "_D3std6string12__ModuleInfoZ" [...../hello.ko] undefined!
Nov 14 21:12:39 eeepc1104 kernel: [17127.068990] hello: Unknown symbol
_D3std6string12__ModuleInfoZ (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.069613] hello: Unknown symbol
register_chrdev (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.070462] hello: Unknown symbol
_D15TypeInfo_Struct6__vtblZ (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.071359] hello: Unknown symbol
_Dmodule_ref (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.072352] hello: Unknown symbol
_D3std6string9toStringzFAaZPa (err 0)
Any help greatly appreciated.
Greetings
Michael
[1] http://tldp.org/LDP/lkmpg/2.6/html/lkmpg.html#AEN680
[2]
http://iainbuclaw.wordpress.com/2010/05/22/writing-a-linux-kernel-module-in-d/
Nov 14 2011
Michael Kremser <mkspamx-usenet yahoo.de> writes:
Hi!
I currently try to create a simple linux driver (for test purposes)
just like in [1] in D based on [2]. The main difficulty is to call
register_chrdev. It expects an argument "fops" of type file_operations
which can look like that in C:
static struct file_operations fops = {
.read = device_read,
.write = device_write,
.open = device_open,
.release = device_release
};
device_read and so on are functions. Originally, file_operations has
much more fields and it's possible to omit unused fields.
What I tried so far: I declared "register_chrdev" as follows:
extern (C):
int register_chrdev (uint major, char *name, file_operations *fops);
My try for the translation of file_operations looks like that:
struct file_operations {
int function() open;
int function() release;
};
In init_module() I have the following code:
char[] DEVICE_NAME = "dtestdev";
file_operations fops;
fops.open = &device_open;
fops.release = &device_close;
Major = register_chrdev(0, std.string.toStringz(DEVICE_NAME), &fops);
The code compiles with some warnings, and if I try to insert it into
the kernel, I get some messages in the kernel log.
WARNING: "_D3std6string9toStringzFAaZPa" [...../hello.ko] undefined!
WARNING: "_Dmodule_ref" [...../hello.ko] undefined!
WARNING: "_D15TypeInfo_Struct6__vtblZ" [...../hello.ko] undefined!
WARNING: "register_chrdev" [...../hello.ko] undefined!
WARNING: "_D3std6string12__ModuleInfoZ" [...../hello.ko] undefined!
Nov 14 21:12:39 eeepc1104 kernel: [17127.068990] hello: Unknown symbol
_D3std6string12__ModuleInfoZ (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.069613] hello: Unknown symbol
register_chrdev (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.070462] hello: Unknown symbol
_D15TypeInfo_Struct6__vtblZ (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.071359] hello: Unknown symbol
_Dmodule_ref (err 0)
Nov 14 21:12:39 eeepc1104 kernel: [17127.072352] hello: Unknown symbol
_D3std6string9toStringzFAaZPa (err 0)
Any help greatly appreciated.
This looks like you don't have druntime or phobos linked into your
module code.
Does the original C example work for you?
Nov 14 2011
Jerry thought it would be a good idea to write me on 15.11.2011 05:01 GMT +0100 (CET):This looks like you don't have druntime or phobos linked into your module code.My Makefile looks as follows: DC := gdc DOBJS := dinterface.o ifneq ($(MAKE_KBUILD),) obj-$(CONFIG_HELLO) := hello.o hello-y += $(DOBJS) else KERNELDIR := /lib/modules/$(shell uname -r)/build all: $(DOBJS) $(MAKE) -C $(KERNELDIR) M=$(shell pwd) CONFIG_HELLO=m MAKE_KBUILD=1 modules clean: $(MAKE) -C $(KERNELDIR) M=$(shell pwd) MAKE_KBUILD=1 clean %.o: %.d $(DC) -c $< -o $ endif Is there something missing?Does the original C example work for you?Yes, it works, and also the "Hello World" module in D from the other webpage works.
Nov 15 2011
Bernard Helyer <b.helyer gmail.com> kbuild is almost certainly not linking in phobos.
Nov 15 2011
On 14 November 2011 20:54, Michael Kremser <mkspamx-usenet yahoo.de> wrote:Hi! I currently try to create a simple linux driver (for test purposes) just like in [1] in D based on [2]. The main difficulty is to call register_chrdev. It expects an argument "fops" of type file_operations wh=ichcan look like that in C: static struct file_operations fops =3D { =A0 =A0 =A0 =A0.read =3D device_read, =A0 =A0 =A0 =A0.write =3D device_write, =A0 =A0 =A0 =A0.open =3D device_open, =A0 =A0 =A0 =A0.release =3D device_release }; device_read and so on are functions. Originally, file_operations has much more fields and it's possible to omit unused fields. What I tried so far: I declared "register_chrdev" as follows: extern (C): int register_chrdev (uint major, char *name, file_operations *fops); My try for the translation of file_operations looks like that: struct file_operations { =A0 =A0 =A0 =A0int function() open; =A0 =A0 =A0 =A0int function() release; }; In init_module() I have the following code: char[] DEVICE_NAME =3D "dtestdev"; file_operations fops; fops.open =3D &device_open; fops.release =3D &device_close; Major =3D register_chrdev(0, std.string.toStringz(DEVICE_NAME), &fops); The code compiles with some warnings, and if I try to insert it into the kernel, I get some messages in the kernel log. WARNING: "_D3std6string9toStringzFAaZPa" [...../hello.ko] undefined! WARNING: "_Dmodule_ref" [...../hello.ko] undefined! WARNING: "_D15TypeInfo_Struct6__vtblZ" [...../hello.ko] undefined! WARNING: "register_chrdev" [...../hello.ko] undefined! WARNING: "_D3std6string12__ModuleInfoZ" [...../hello.ko] undefined! Nov 14 21:12:39 eeepc1104 kernel: [17127.068990] hello: Unknown symbol _D3std6string12__ModuleInfoZ (err 0) Nov 14 21:12:39 eeepc1104 kernel: [17127.069613] hello: Unknown symbol register_chrdev (err 0) Nov 14 21:12:39 eeepc1104 kernel: [17127.070462] hello: Unknown symbol _D15TypeInfo_Struct6__vtblZ (err 0) Nov 14 21:12:39 eeepc1104 kernel: [17127.071359] hello: Unknown symbol _Dmodule_ref (err 0) Nov 14 21:12:39 eeepc1104 kernel: [17127.072352] hello: Unknown symbol _D3std6string9toStringzFAaZPa (err 0) Any help greatly appreciated. Greetings Michael [1] http://tldp.org/LDP/lkmpg/2.6/html/lkmpg.html#AEN680 [2] http://iainbuclaw.wordpress.com/2010/05/22/writing-a-linux-kernel-module-=in-d/If you are going to write a kernel module, do not use or rely any part of the D, or C standard library. Do not attempt to do anything that would generate hidden calls to the D runtime library, or would depend on there being one. Otherwise you will find yourself hitting a total system freeze when loading the module into the kernel. :~) Rather than using toStringz, you should be able to get by with declaring the register_chrdev function as follows. extern(C) int register_chrdev (uint major, in char *name, file_operations *fops) Regards --=20 Iain Buclaw *(p < e ? p++ : p) =3D (c & 0x0f) + '0';
Nov 15 2011
Am 2011-11-16 00:53, schrieb Iain Buclaw:Rather than using toStringz, you should be able to get by with declaring the register_chrdev function as follows. extern(C) int register_chrdev (uint major, in char *name, file_operations *fops)This yields the following compiler error: Error: cannot implicitly convert expression (DEVICE_NAME) of type char[] to char* If I try to cast with register_chrdev(0, (char*)DEVICE_NAME, &fops); the following error appears: C style cast illegal, use cast(char*)DEVICE_NAME Best regards Michael
Nov 16 2011
If I try to cast with register_chrdev(0, (char*)DEVICE_NAME, &fops); the following error appears: C style cast illegal, use cast(char*)DEVICE_NAMEOr use DEVICE_NAME.ptr
Nov 16 2011
Am 2011-11-16 23:23, schrieb Trass3r:Compilation now succeeded, but when I try to load with insmod, the following errors appear: Nov 17 15:03:49 eeepc1104 kernel: [43799.326876] hello: Unknown symbol _D3std6string12__ModuleInfoZ (err 0) Nov 17 15:03:49 eeepc1104 kernel: [43799.327297] hello: Unknown symbol register_chrdev (err 0) Nov 17 15:03:49 eeepc1104 kernel: [43799.327702] hello: Unknown symbol _D15TypeInfo_Struct6__vtblZ (err 0) Nov 17 15:03:49 eeepc1104 kernel: [43799.328252] hello: Unknown symbol Best regards MichaelIf I try to cast with register_chrdev(0, (char*)DEVICE_NAME, &fops); the following error appears: C style cast illegal, use cast(char*)DEVICE_NAMEOr use DEVICE_NAME.ptr
Nov 17 2011