hello... For my project, i'm now generating IPC stubs using DICE, so that i can i have my L4 server beeing call from L4Linux. But just for trying, i'm defining the interface, server, library, and a simple client only for testing. Here is my interface: ##################################################################### typedef struct WOO_Send_Retval_struct{ int error; [string]char *tag; }WOO_Send_Retval; typedef struct WOO_Receive_Retval_struct{ int error; [string]char *tag; }WOO_Receive_Retval; typedef struct WOO_Decide_Retval_struct{ int error; long order_num; char hash[20]; }WOO_Decide_Retval; interface WOO{ int init(void); WOO_Send_Retval send([in]long long starter_eid, [in, max_is(100), size_is(eids_num)]long long eids[], [in]int eids_num, [in]long msg_id, [in, string]char *hash); }; ##################################################################### i've built also a server: ##################################################################### /* * This file is auto generated by Dice-2.2.8. * * Implement the server templates here. * This file is regenerated with every run of 'dice -t ...'. * Move it to another location after changing to * keep your changes! */ #include <stdio.h> #include <l4/log/l4log.h> #include <l4/names/libnames.h> #include <stdlib.h> #include "WOO-server.h" char LOG_tag[9]="wooserver"; #ifdef __cplusplus extern "C" { #endif CORBA_int WOO_init_component(CORBA_Object _dice_corba_obj, CORBA_Server_Environment *_dice_corba_env) { int retval = 232144; return retval; } WOO_Send_Retval WOO_send_component(CORBA_Object _dice_corba_obj, CORBA_long_long starter_eid, const CORBA_long_long eids[100], CORBA_int eids_num, CORBA_long msg_id, const_CORBA_char_ptr hash, CORBA_Server_Environment *_dice_corba_env) { WOO_Send_Retval retval; LOG("i've got the call:: hash = %s\n", hash); retval.error = 34; retval.tag = "teststring"; LOG("return\n"); return retval; } int main(void){ if(names_register("wooserver")==0){ printf("Error registering at nameserver\n"); return 1; } WOO_server_loop(0); } #ifdef __cplusplus } #endif ##################################################################### and a libray to call the server: ##################################################################### #include <l4/names/libnames.h> #include <l4/log/l4log.h> #include <l4/env/errno.h> #include <l4/sys/consts.h> #include <l4/WOO_ipc/WOO_helper.h> #include <stdlib.h> static l4_threadid_t server_id = L4_INVALID_ID; static CORBA_Object server = &server_id; //! Request netserver id at nameserver static int check_server(void){ if (l4_is_invalid_id(server_id)){ LOG("inicio do programa\n"); if (!names_waitfor_name("wooserver",&server_id,10000)){ LOG("nao ha nome disponivel\n"); return 1; } } return 0; } //! woo_init int WOO_init(void){ CORBA_Environment env = dice_default_environment; int retval; LOG("chamaram o woo_init\n"); if (check_server()) return -L4_EINVAL; LOG("fiz o call\n"); retval = WOO_init_call(server, &env); LOG("a call retornou\n"); if(!env._p.ipc_error) return retval; LOG("ERROR\n"); return -env._p.ipc_error; } //! woo_send WOO_Send_Retval WOO_send(void){ CORBA_Environment env = dice_default_environment; WOO_Send_Retval retval; long long eids[100]; char tag[20] = "htkilfndtigkmnefktlo"; LOG("call woo send\n"); eids[0] = 213424; eids[1] = 2314124; eids[2] = 2143441; if (check_server()){ retval.error = -L4_EINVAL; return retval; } LOG("do the call\n"); retval=WOO_send_call(server, 12344512, eids, 3, 453445, tag, &env); LOG("call return\n"); if(!env._p.ipc_error) return retval; retval.error = -env._p.ipc_error; return retval; } ##################################################################### and a simple client: ##################################################################### #include <stdio.h> #include <l4/log/l4log.h> #include <l4/WOO_ipc/WOO_helper.h> char LOG_tag[9]="WOOclient"; int main(void){ int wooinitret; WOO_Send_Retval ret; LOG("client start\n"); wooinitret = WOO_init(); LOG("woo_init()\n"); LOG("WOO init returned %d\n", wooinitret); LOG("woo_send()\n"); ret = WOO_send(); LOG("returned send\n"); LOG("WOO send tag= %s\n", ret.tag); return 0; } ##################################################################### all ok, until i get it to run... There, he gives me an error (page fault) at the stubs, when unmarshalling the return value of the woo_send() call, more precisely, when allocating the string(tag) inside the return structure. the line is the following: _dice_return.tag = (CORBA_char_ptr)(_dice_corba_env->malloc)(_dice_tmp_offset); i've checked the string size tha comes from the server and it is correct... So... why is it page faulting?? thanks in advance Tiago Jorge
Hello!
all ok, until i get it to run... There, he gives me an error (page fault) at the stubs, when unmarshalling the return value of the woo_send() call, more precisely, when allocating the string(tag) inside the return structure. the line is the following:
_dice_return.tag = (CORBA_char_ptr)(_dice_corba_env->malloc)(_dice_tmp_offset);
i've checked the string size tha comes from the server and it is correct...
So... why is it page faulting??
The _dice_corba_env->malloc pointer is zero, isn't it? You could give the server-loop another dice_corba-environment, (look at the dice parameter -fserver-parameter) that contain a malloc, instead of using the default one at "WOO_server_loop(0);" Or you can take a look at the dice parameter -fforce-corba-alloc and implement a CORBA_alloc() and CORBA_free() ... Greetings Bernhard Kauer
Hi, Tiago Jorge wrote: <snip>
WOO_Send_Retval WOO_send(void){ CORBA_Environment env = dice_default_environment;
<snip>
#####################################################################
all ok, until i get it to run... There, he gives me an error (page fault) at the stubs, when unmarshalling the return value of the woo_send() call, more precisely, when allocating the string(tag) inside the return structure. the line is the following:
_dice_return.tag = (CORBA_char_ptr)(_dice_corba_env->malloc)(_dice_tmp_offset);
i've checked the string size tha comes from the server and it is correct...
So... why is it page faulting?? That's strange. What version of dice are you using? With the above code it should not pagefault, but instead jump into the kernel-debugger.
Ok. You are using the default environment, which contains function pointers to malloc and free functions to allocate memory for such things as string returned from the server. These functions are (in old versions of dice set to NULL -> pagefault) or a default function (in the latest version), which jumps into the kernel debugger (to allow to see why its pagefaulting :). If you turn on warnings when using dice (-Wall or see --help for other options) it tells you when and for which variable it uses malloc. The idea is, that you can provide your own versions of malloc and free (just have to have the same signature) and set them in the local environment: CORBA_Environment env = dice_default_environment; env.malloc = (dice_malloc)malloc; The cast is to eliminate a warning: the libc malloc usually uses size_t type, which is not defined in L4Env. Hope that helps, Ron. -- With regards Ronald Aigner @ ST Microelectronics aigner.eurecom@st.com
That's strange. What version of dice are you using? With the above code it should not pagefault, but instead jump into the kernel-debugger.
thanks for your answers. Don't panic...:). When i say its page faulting its AFTER entering the kernel debugger.
Ok. You are using the default environment, which contains function pointers to malloc and free functions to allocate memory for such things as string returned from the server. These functions are (in old versions of dice set to NULL -> pagefault) or a default function (in the latest version), which jumps into the kernel debugger (to allow to see why its pagefaulting :). If you turn on warnings when using dice (-Wall or see --help for other options) it tells you when and for which variable it uses malloc. The idea is, that you can provide your own versions of malloc and free (just have to have the same signature) and set them in the local environment:
CORBA_Environment env = dice_default_environment; env.malloc = (dice_malloc)malloc;
The cast is to eliminate a warning: the libc malloc usually uses size_t type, which is not defined in L4Env.
i'm gonna try it right now.
Hope that helps, Ron.
thanks again :) Tiago
participants (3)
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Bernhard Kauer -
Ronald AIGNER -
Tiago Jorge