/* Copyright (C) 1992, 1993, 1994, 1997, 1998, 1999, 2000, 2003, 2004, 2005, 2007, 2008, 2009 Free Software Foundation, Inc. This file is part of GDB. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ #include "defs.h" #include "observer.h" #include "gdbcmd.h" #include "target.h" #include "ada-lang.h" #include "gdbcore.h" #include "inferior.h" #include "gdbthread.h" /* The name of the array in the GNAT runtime where the Ada Task Control Block of each task is stored. */ #define KNOWN_TASKS_NAME "system__tasking__debug__known_tasks" /* The maximum number of tasks known to the Ada runtime */ static const int MAX_NUMBER_OF_KNOWN_TASKS = 1000; enum task_states { Unactivated, Runnable, Terminated, Activator_Sleep, Acceptor_Sleep, Entry_Caller_Sleep, Async_Select_Sleep, Delay_Sleep, Master_Completion_Sleep, Master_Phase_2_Sleep, Interrupt_Server_Idle_Sleep, Interrupt_Server_Blocked_Interrupt_Sleep, Timer_Server_Sleep, AST_Server_Sleep, Asynchronous_Hold, Interrupt_Server_Blocked_On_Event_Flag, Activating, Acceptor_Delay_Sleep }; /* A short description corresponding to each possible task state. */ static const char *task_states[] = { N_("Unactivated"), N_("Runnable"), N_("Terminated"), N_("Child Activation Wait"), N_("Accept or Select Term"), N_("Waiting on entry call"), N_("Async Select Wait"), N_("Delay Sleep"), N_("Child Termination Wait"), N_("Wait Child in Term Alt"), "", "", "", "", N_("Asynchronous Hold"), "", N_("Activating"), N_("Selective Wait") }; /* A longer description corresponding to each possible task state. */ static const char *long_task_states[] = { N_("Unactivated"), N_("Runnable"), N_("Terminated"), N_("Waiting for child activation"), N_("Blocked in accept or select with terminate"), N_("Waiting on entry call"), N_("Asynchronous Selective Wait"), N_("Delay Sleep"), N_("Waiting for children termination"), N_("Waiting for children in terminate alternative"), "", "", "", "", N_("Asynchronous Hold"), "", N_("Activating"), N_("Blocked in selective wait statement") }; /* The index of certain important fields in the Ada Task Control Block record and sub-records. */ struct tcb_fieldnos { /* Fields in record Ada_Task_Control_Block. */ int common; int entry_calls; int atc_nesting_level; /* Fields in record Common_ATCB. */ int state; int parent; int priority; int image; int image_len; /* This field may be missing. */ int call; int ll; /* Fields in Task_Primitives.Private_Data. */ int ll_thread; int ll_lwp; /* This field may be missing. */ /* Fields in Common_ATCB.Call.all. */ int call_self; }; /* The type description for the ATCB record and subrecords, and the associated tcb_fieldnos. For efficiency reasons, these are made static globals so that we can compute them only once the first time and reuse them later. Set to NULL if the types haven't been computed yet, or if they may be obsolete (for instance after having loaded a new binary). */ static struct type *atcb_type = NULL; static struct type *atcb_common_type = NULL; static struct type *atcb_ll_type = NULL; static struct type *atcb_call_type = NULL; static struct tcb_fieldnos fieldno; /* Set to 1 when the cached address of System.Tasking.Debug.Known_Tasks might be stale and so needs to be recomputed. */ static int ada_tasks_check_symbol_table = 1; /* The list of Ada tasks. Note: To each task we associate a number that the user can use to reference it - this number is printed beside each task in the tasks info listing displayed by "info tasks". This number is equal to its index in the vector + 1. Reciprocally, to compute the index of a task in the vector, we need to substract 1 from its number. */ typedef struct ada_task_info ada_task_info_s; DEF_VEC_O(ada_task_info_s); static VEC(ada_task_info_s) *task_list = NULL; /* When non-zero, this flag indicates that the current task_list is obsolete, and should be recomputed before it is accessed. */ static int stale_task_list_p = 1; /* Return the task number of the task whose ptid is PTID, or zero if the task could not be found. */ int ada_get_task_number (ptid_t ptid) { int i; for (i=0; i < VEC_length (ada_task_info_s, task_list); i++) if (ptid_equal (VEC_index (ada_task_info_s, task_list, i)->ptid, ptid)) return i + 1; return 0; /* No matching task found. */ } /* Return the task number of the task that matches TASK_ID, or zero if the task could not be found. */ static int get_task_number_from_id (CORE_ADDR task_id) { int i; for (i = 0; i < VEC_length (ada_task_info_s, task_list); i++) { struct ada_task_info *task_info = VEC_index (ada_task_info_s, task_list, i); if (task_info->task_id == task_id) return i + 1; } /* Task not found. Return 0. */ return 0; } /* Return non-zero if TASK_NUM is a valid task number. */ int valid_task_id (int task_num) { return (task_num > 0 && task_num <= VEC_length (ada_task_info_s, task_list)); } /* Return non-zero iff the task STATE corresponds to a non-terminated task state. */ static int ada_task_is_alive (struct ada_task_info *task_info) { return (task_info->state != Terminated); } /* Extract the contents of the value as a string whose length is LENGTH, and store the result in DEST. */ static void value_as_string (char *dest, struct value *val, int length) { memcpy (dest, value_contents (val), length); dest[length] = '\0'; } /* Extract the string image from the fat string corresponding to VAL, and store it in DEST. If the string length is greater than MAX_LEN, then truncate the result to the first MAX_LEN characters of the fat string. */ static void read_fat_string_value (char *dest, struct value *val, int max_len) { struct value *array_val; struct value *bounds_val; int len; /* The following variables are made static to avoid recomputing them each time this function is called. */ static int initialize_fieldnos = 1; static int array_fieldno; static int bounds_fieldno; static int upper_bound_fieldno; /* Get the index of the fields that we will need to read in order to extract the string from the fat string. */ if (initialize_fieldnos) { struct type *type = value_type (val); struct type *bounds_type; array_fieldno = ada_get_field_index (type, "P_ARRAY", 0); bounds_fieldno = ada_get_field_index (type, "P_BOUNDS", 0); bounds_type = TYPE_FIELD_TYPE (type, bounds_fieldno); if (TYPE_CODE (bounds_type) == TYPE_CODE_PTR) bounds_type = TYPE_TARGET_TYPE (bounds_type); if (TYPE_CODE (bounds_type) != TYPE_CODE_STRUCT) error (_("Unknown task name format. Aborting")); upper_bound_fieldno = ada_get_field_index (bounds_type, "UB0", 0); initialize_fieldnos = 0; } /* Get the size of the task image by checking the value of the bounds. The lower bound is always 1, so we only need to read the upper bound. */ bounds_val = value_ind (value_field (val, bounds_fieldno)); len = value_as_long (value_field (bounds_val, upper_bound_fieldno)); /* Make sure that we do not read more than max_len characters... */ if (len > max_len) len = max_len; /* Extract LEN characters from the fat string. */ array_val = value_ind (value_field (val, array_fieldno)); read_memory (value_address (array_val), dest, len); /* Add the NUL character to close the string. */ dest[len] = '\0'; } /* Return the address of the Known_Tasks array maintained in the Ada Runtime. Return NULL if the array could not be found, meaning that the inferior program probably does not use tasking. In order to provide a fast response time, this function caches the Known_Tasks array address after the lookup during the first call. Subsequent calls will simply return this cached address. */ static CORE_ADDR get_known_tasks_addr (void) { static CORE_ADDR known_tasks_addr = 0; if (ada_tasks_check_symbol_table) { struct symbol *sym; struct minimal_symbol *msym; msym = lookup_minimal_symbol (KNOWN_TASKS_NAME, NULL, NULL); if (msym != NULL) known_tasks_addr = SYMBOL_VALUE_ADDRESS (msym); else { if (target_lookup_symbol (KNOWN_TASKS_NAME, &known_tasks_addr) != 0) return 0; } /* FIXME: brobecker 2003-03-05: Here would be a much better place to attach the ada-tasks observers, instead of doing this unconditionaly in _initialize_tasks. This would avoid an unecessary notification when the inferior does not use tasking or as long as the user does not use the ada-tasks commands. Unfortunately, this is not possible for the moment: the current code resets ada__tasks_check_symbol_table back to 1 whenever symbols for a new program are being loaded. If we place the observers intialization here, we will end up adding new observers everytime we do the check for Ada tasking-related symbols above. This would currently have benign effects, but is still undesirable. The cleanest approach is probably to create a new observer to notify us when the user is debugging a new program. We would then reset ada__tasks_check_symbol_table back to 1 during the notification, but also detach all observers. BTW: observers are probably not reentrant, so detaching during a notification may not be the safest thing to do... Sigh... But creating the new observer would be a good idea in any case, since this allow us to make ada__tasks_check_symbol_table static, which is a good bonus. */ ada_tasks_check_symbol_table = 0; } return known_tasks_addr; } /* Get from the debugging information the type description of all types related to the Ada Task Control Block that will be needed in order to read the list of known tasks in the Ada runtime. Also return the associated ATCB_FIELDNOS. Error handling: Any data missing from the debugging info will cause an error to be raised, and none of the return values to be set. Users of this function can depend on the fact that all or none of the return values will be set. */ static void get_tcb_types_info (struct type **atcb_type, struct type **atcb_common_type, struct type **atcb_ll_type, struct type **atcb_call_type, struct tcb_fieldnos *atcb_fieldnos) { struct type *type; struct type *common_type; struct type *ll_type; struct type *call_type; struct tcb_fieldnos fieldnos; const char *atcb_name = "system__tasking__ada_task_control_block___XVE"; const char *atcb_name_fixed = "system__tasking__ada_task_control_block"; const char *common_atcb_name = "system__tasking__common_atcb"; const char *private_data_name = "system__task_primitives__private_data"; const char *entry_call_record_name = "system__tasking__entry_call_record"; struct symbol *atcb_sym = lookup_symbol (atcb_name, NULL, VAR_DOMAIN, NULL); const struct symbol *common_atcb_sym = lookup_symbol (common_atcb_name, NULL, VAR_DOMAIN, NULL); const struct symbol *private_data_sym = lookup_symbol (private_data_name, NULL, VAR_DOMAIN, NULL); const struct symbol *entry_call_record_sym = lookup_symbol (entry_call_record_name, NULL, VAR_DOMAIN, NULL); if (atcb_sym == NULL || atcb_sym->type == NULL) { /* In Ravenscar run-time libs, the ATCB does not have a dynamic size, so the symbol name differs. */ atcb_sym = lookup_symbol (atcb_name_fixed, NULL, VAR_DOMAIN, NULL); if (atcb_sym == NULL || atcb_sym->type == NULL) error (_("Cannot find Ada_Task_Control_Block type. Aborting")); type = atcb_sym->type; } else { /* Get a static representation of the type record Ada_Task_Control_Block. */ type = atcb_sym->type; type = ada_template_to_fixed_record_type_1 (type, NULL, 0, NULL, 0); } if (common_atcb_sym == NULL || common_atcb_sym->type == NULL) error (_("Cannot find Common_ATCB type. Aborting")); if (private_data_sym == NULL || private_data_sym->type == NULL) error (_("Cannot find Private_Data type. Aborting")); if (entry_call_record_sym == NULL || entry_call_record_sym->type == NULL) error (_("Cannot find Entry_Call_Record type. Aborting")); /* Get the type for Ada_Task_Control_Block.Common. */ common_type = common_atcb_sym->type; /* Get the type for Ada_Task_Control_Bloc.Common.Call.LL. */ ll_type = private_data_sym->type; /* Get the type for Common_ATCB.Call.all. */ call_type = entry_call_record_sym->type; /* Get the field indices. */ fieldnos.common = ada_get_field_index (type, "common", 0); fieldnos.entry_calls = ada_get_field_index (type, "entry_calls", 1); fieldnos.atc_nesting_level = ada_get_field_index (type, "atc_nesting_level", 1); fieldnos.state = ada_get_field_index (common_type, "state", 0); fieldnos.parent = ada_get_field_index (common_type, "parent", 1); fieldnos.priority = ada_get_field_index (common_type, "base_priority", 0); fieldnos.image = ada_get_field_index (common_type, "task_image", 1); fieldnos.image_len = ada_get_field_index (common_type, "task_image_len", 1); fieldnos.call = ada_get_field_index (common_type, "call", 1); fieldnos.ll = ada_get_field_index (common_type, "ll", 0); fieldnos.ll_thread = ada_get_field_index (ll_type, "thread", 0); fieldnos.ll_lwp = ada_get_field_index (ll_type, "lwp", 1); fieldnos.call_self = ada_get_field_index (call_type, "self", 0); /* On certain platforms such as x86-windows, the "lwp" field has been named "thread_id". This field will likely be renamed in the future, but we need to support both possibilities to avoid an unnecessary dependency on a recent compiler. We therefore try locating the "thread_id" field in place of the "lwp" field if we did not find the latter. */ if (fieldnos.ll_lwp < 0) fieldnos.ll_lwp = ada_get_field_index (ll_type, "thread_id", 1); /* Set all the out parameters all at once, now that we are certain that there are no potential error() anymore. */ *atcb_type = type; *atcb_common_type = common_type; *atcb_ll_type = ll_type; *atcb_call_type = call_type; *atcb_fieldnos = fieldnos; } /* Build the PTID of the task from its COMMON_VALUE, which is the "Common" component of its ATCB record. This PTID needs to match the PTID used by the thread layer. */ static ptid_t ptid_from_atcb_common (struct value *common_value) { long thread = 0; CORE_ADDR lwp = 0; struct value *ll_value; ptid_t ptid; ll_value = value_field (common_value, fieldno.ll); if (fieldno.ll_lwp >= 0) lwp = value_as_address (value_field (ll_value, fieldno.ll_lwp)); thread = value_as_long (value_field (ll_value, fieldno.ll_thread)); ptid = target_get_ada_task_ptid (lwp, thread); return ptid; } /* Read the ATCB data of a given task given its TASK_ID (which is in practice the address of its assocated ATCB record), and store the result inside TASK_INFO. */ static void read_atcb (CORE_ADDR task_id, struct ada_task_info *task_info) { struct value *tcb_value; struct value *common_value; struct value *atc_nesting_level_value; struct value *entry_calls_value; struct value *entry_calls_value_element; int called_task_fieldno = -1; const char ravenscar_task_name[] = "Ravenscar task"; if (atcb_type == NULL) get_tcb_types_info (&atcb_type, &atcb_common_type, &atcb_ll_type, &atcb_call_type, &fieldno); tcb_value = value_from_contents_and_address (atcb_type, NULL, task_id); common_value = value_field (tcb_value, fieldno.common); /* Fill in the task_id. */ task_info->task_id = task_id; /* Compute the name of the task. Depending on the GNAT version used, the task image is either a fat string, or a thin array of characters. Older versions of GNAT used to use fat strings, and therefore did not need an extra field in the ATCB to store the string length. For efficiency reasons, newer versions of GNAT replaced the fat string by a static buffer, but this also required the addition of a new field named "Image_Len" containing the length of the task name. The method used to extract the task name is selected depending on the existence of this field. In some run-time libs (e.g. Ravenscar), the name is not in the ATCB; we may want to get it from the first user frame of the stack. For now, we just give a dummy name. */ if (fieldno.image_len == -1) { if (fieldno.image >= 0) read_fat_string_value (task_info->name, value_field (common_value, fieldno.image), sizeof (task_info->name) - 1); else strcpy (task_info->name, ravenscar_task_name); } else { int len = value_as_long (value_field (common_value, fieldno.image_len)); value_as_string (task_info->name, value_field (common_value, fieldno.image), len); } /* Compute the task state and priority. */ task_info->state = value_as_long (value_field (common_value, fieldno.state)); task_info->priority = value_as_long (value_field (common_value, fieldno.priority)); /* If the ATCB contains some information about the parent task, then compute it as well. Otherwise, zero. */ if (fieldno.parent >= 0) task_info->parent = value_as_address (value_field (common_value, fieldno.parent)); else task_info->parent = 0; /* If the ATCB contains some information about entry calls, then compute the "called_task" as well. Otherwise, zero. */ if (fieldno.atc_nesting_level > 0 && fieldno.entry_calls > 0) { /* Let My_ATCB be the Ada task control block of a task calling the entry of another task; then the Task_Id of the called task is in My_ATCB.Entry_Calls (My_ATCB.ATC_Nesting_Level).Called_Task. */ atc_nesting_level_value = value_field (tcb_value, fieldno.atc_nesting_level); entry_calls_value = ada_coerce_to_simple_array_ptr (value_field (tcb_value, fieldno.entry_calls)); entry_calls_value_element = value_subscript (entry_calls_value, value_as_long (atc_nesting_level_value)); called_task_fieldno = ada_get_field_index (value_type (entry_calls_value_element), "called_task", 0); task_info->called_task = value_as_address (value_field (entry_calls_value_element, called_task_fieldno)); } else { task_info->called_task = 0; } /* If the ATCB cotnains some information about RV callers, then compute the "caller_task". Otherwise, zero. */ task_info->caller_task = 0; if (fieldno.call >= 0) { /* Get the ID of the caller task from Common_ATCB.Call.all.Self. If Common_ATCB.Call is null, then there is no caller. */ const CORE_ADDR call = value_as_address (value_field (common_value, fieldno.call)); struct value *call_val; if (call != 0) { call_val = value_from_contents_and_address (atcb_call_type, NULL, call); task_info->caller_task = value_as_address (value_field (call_val, fieldno.call_self)); } } /* And finally, compute the task ptid. */ if (ada_task_is_alive (task_info)) task_info->ptid = ptid_from_atcb_common (common_value); else task_info->ptid = null_ptid; } /* Read the ATCB info of the given task (identified by TASK_ID), and add the result to the TASK_LIST. */ static void add_ada_task (CORE_ADDR task_id) { struct ada_task_info task_info; read_atcb (task_id, &task_info); VEC_safe_push (ada_task_info_s, task_list, &task_info); } /* Read the Known_Tasks array from the inferior memory, and store it in TASK_LIST. Return non-zero upon success. */ static int read_known_tasks_array (void) { const int target_ptr_byte = gdbarch_ptr_bit (target_gdbarch) / TARGET_CHAR_BIT; const CORE_ADDR known_tasks_addr = get_known_tasks_addr (); const int known_tasks_size = target_ptr_byte * MAX_NUMBER_OF_KNOWN_TASKS; gdb_byte *known_tasks = alloca (known_tasks_size); int i; /* Step 1: Clear the current list, if necessary. */ VEC_truncate (ada_task_info_s, task_list, 0); /* If the application does not use task, then no more needs to be done. It is important to have the task list cleared (see above) before we return, as we don't want a stale task list to be used... This can happen for instance when debugging a non-multitasking program after having debugged a multitasking one. */ if (known_tasks_addr == 0) return 0; /* Step 2: Build a new list by reading the ATCBs from the Known_Tasks array in the Ada runtime. */ read_memory (known_tasks_addr, known_tasks, known_tasks_size); for (i = 0; i < MAX_NUMBER_OF_KNOWN_TASKS; i++) { struct type *data_ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr; CORE_ADDR task_id = extract_typed_address (known_tasks + i * target_ptr_byte, data_ptr_type); if (task_id != 0) add_ada_task (task_id); } /* Step 3: Unset stale_task_list_p, to avoid re-reading the Known_Tasks array unless needed. Then report a success. */ stale_task_list_p = 0; return 1; } /* Builds the task_list by reading the Known_Tasks array from the inferior. Prints an appropriate message and returns non-zero if it failed to build this list. */ int ada_build_task_list (int warn_if_null) { if (!target_has_stack) error (_("Cannot inspect Ada tasks when program is not running")); if (stale_task_list_p) read_known_tasks_array (); if (task_list == NULL) { if (warn_if_null) printf_filtered (_("Your application does not use any Ada tasks.\n")); return 0; } return 1; } /* Print a one-line description of the task whose number is TASKNO. The formatting should fit the "info tasks" array. */ static void short_task_info (int taskno) { const struct ada_task_info *const task_info = VEC_index (ada_task_info_s, task_list, taskno - 1); int active_task_p; gdb_assert (task_info != NULL); /* Print a star if this task is the current task (or the task currently selected). */ active_task_p = ptid_equal (task_info->ptid, inferior_ptid); if (active_task_p) printf_filtered ("*"); else printf_filtered (" "); /* Print the task number. */ printf_filtered ("%3d", taskno); /* Print the Task ID. */ printf_filtered (" %9lx", (long) task_info->task_id); /* Print the Task ID of the task parent. */ printf_filtered (" %4d", get_task_number_from_id (task_info->parent)); /* Print the base priority of the task. */ printf_filtered (" %3d", task_info->priority); /* Print the task current state. */ if (task_info->caller_task) printf_filtered (_(" Accepting RV with %-4d"), get_task_number_from_id (task_info->caller_task)); else if (task_info->state == Entry_Caller_Sleep && task_info->called_task) printf_filtered (_(" Waiting on RV with %-3d"), get_task_number_from_id (task_info->called_task)); else printf_filtered (" %-22s", _(task_states[task_info->state])); /* Finally, print the task name. */ if (task_info->name[0] != '\0') printf_filtered (" %s\n", task_info->name); else printf_filtered (_(" \n")); } /* Print a list containing a short description of all Ada tasks. */ /* FIXME: Shouldn't we be using ui_out??? */ static void info_tasks (int from_tty) { int taskno; const int nb_tasks = VEC_length (ada_task_info_s, task_list); printf_filtered (_(" ID TID P-ID Pri State Name\n")); for (taskno = 1; taskno <= nb_tasks; taskno++) short_task_info (taskno); } /* Print a detailed description of the Ada task whose ID is TASKNO_STR. */ static void info_task (char *taskno_str, int from_tty) { const int taskno = value_as_long (parse_and_eval (taskno_str)); struct ada_task_info *task_info; int parent_taskno = 0; if (taskno <= 0 || taskno > VEC_length (ada_task_info_s, task_list)) error (_("Task ID %d not known. Use the \"info tasks\" command to\n" "see the IDs of currently known tasks"), taskno); task_info = VEC_index (ada_task_info_s, task_list, taskno - 1); /* Print the Ada task ID. */ printf_filtered (_("Ada Task: %s\n"), paddress (target_gdbarch, task_info->task_id)); /* Print the name of the task. */ if (task_info->name[0] != '\0') printf_filtered (_("Name: %s\n"), task_info->name); else printf_filtered (_("\n")); /* Print the TID and LWP. */ printf_filtered (_("Thread: %#lx\n"), ptid_get_tid (task_info->ptid)); printf_filtered (_("LWP: %#lx\n"), ptid_get_lwp (task_info->ptid)); /* Print who is the parent (if any). */ if (task_info->parent != 0) parent_taskno = get_task_number_from_id (task_info->parent); if (parent_taskno) { struct ada_task_info *parent = VEC_index (ada_task_info_s, task_list, parent_taskno - 1); printf_filtered (_("Parent: %d"), parent_taskno); if (parent->name[0] != '\0') printf_filtered (" (%s)", parent->name); printf_filtered ("\n"); } else printf_filtered (_("No parent\n")); /* Print the base priority. */ printf_filtered (_("Base Priority: %d\n"), task_info->priority); /* print the task current state. */ { int target_taskno = 0; if (task_info->caller_task) { target_taskno = get_task_number_from_id (task_info->caller_task); printf_filtered (_("State: Accepting rendezvous with %d"), target_taskno); } else if (task_info->state == Entry_Caller_Sleep && task_info->called_task) { target_taskno = get_task_number_from_id (task_info->called_task); printf_filtered (_("State: Waiting on task %d's entry"), target_taskno); } else printf_filtered (_("State: %s"), _(long_task_states[task_info->state])); if (target_taskno) { struct ada_task_info *target_task_info = VEC_index (ada_task_info_s, task_list, target_taskno - 1); if (target_task_info->name[0] != '\0') printf_filtered (" (%s)", target_task_info->name); } printf_filtered ("\n"); } } /* If ARG is empty or null, then print a list of all Ada tasks. Otherwise, print detailed information about the task whose ID is ARG. Does nothing if the program doesn't use Ada tasking. */ static void info_tasks_command (char *arg, int from_tty) { const int task_list_built = ada_build_task_list (1); if (!task_list_built) return; if (arg == NULL || *arg == '\0') info_tasks (from_tty); else info_task (arg, from_tty); } /* Print a message telling the user id of the current task. This function assumes that tasking is in use in the inferior. */ static void display_current_task_id (void) { const int current_task = ada_get_task_number (inferior_ptid); if (current_task == 0) printf_filtered (_("[Current task is unknown]\n")); else printf_filtered (_("[Current task is %d]\n"), current_task); } /* Parse and evaluate TIDSTR into a task id, and try to switch to that task. Print an error message if the task switch failed. */ static void task_command_1 (char *taskno_str, int from_tty) { const int taskno = value_as_long (parse_and_eval (taskno_str)); struct ada_task_info *task_info; if (taskno <= 0 || taskno > VEC_length (ada_task_info_s, task_list)) error (_("Task ID %d not known. Use the \"info tasks\" command to\n" "see the IDs of currently known tasks"), taskno); task_info = VEC_index (ada_task_info_s, task_list, taskno - 1); if (!ada_task_is_alive (task_info)) error (_("Cannot switch to task %d: Task is no longer running"), taskno); /* On some platforms, the thread list is not updated until the user performs a thread-related operation (by using the "info threads" command, for instance). So this thread list may not be up to date when the user attempts this task switch. Since we cannot switch to the thread associated to our task if GDB does not know about that thread, we need to make sure that any new threads gets added to the thread list. */ target_find_new_threads (); switch_to_thread (task_info->ptid); ada_find_printable_frame (get_selected_frame (NULL)); printf_filtered (_("[Switching to task %d]\n"), taskno); print_stack_frame (get_selected_frame (NULL), frame_relative_level (get_selected_frame (NULL)), 1); } /* Print the ID of the current task if TASKNO_STR is empty or NULL. Otherwise, switch to the task indicated by TASKNO_STR. */ static void task_command (char *taskno_str, int from_tty) { const int task_list_built = ada_build_task_list (1); if (!task_list_built) return; if (taskno_str == NULL || taskno_str[0] == '\0') display_current_task_id (); else { /* Task switching in core files doesn't work, either because: 1. Thread support is not implemented with core files 2. Thread support is implemented, but the thread IDs created after having read the core file are not the same as the ones that were used during the program life, before the crash. As a consequence, there is no longer a way for the debugger to find the associated thead ID of any given Ada task. So, instead of attempting a task switch without giving the user any clue as to what might have happened, just error-out with a message explaining that this feature is not supported. */ if (!target_has_execution) error (_("\ Task switching not supported when debugging from core files\n\ (use thread support instead)")); task_command_1 (taskno_str, from_tty); } } /* Indicate that the task list may have changed, so invalidate the cache. */ static void ada_task_list_changed (void) { stale_task_list_p = 1; } /* The 'normal_stop' observer notification callback. */ static void ada_normal_stop_observer (struct bpstats *unused_args, int unused_args2) { /* The inferior has been resumed, and just stopped. This means that our task_list needs to be recomputed before it can be used again. */ ada_task_list_changed (); } /* A routine to be called when the objfiles have changed. */ static void ada_new_objfile_observer (struct objfile *objfile) { /* Invalidate all cached data that were extracted from an objfile. */ atcb_type = NULL; atcb_common_type = NULL; atcb_ll_type = NULL; atcb_call_type = NULL; ada_tasks_check_symbol_table = 1; } /* Provide a prototype to silence -Wmissing-prototypes. */ extern initialize_file_ftype _initialize_tasks; void _initialize_tasks (void) { /* Attach various observers. */ observer_attach_normal_stop (ada_normal_stop_observer); observer_attach_new_objfile (ada_new_objfile_observer); /* Some new commands provided by this module. */ add_info ("tasks", info_tasks_command, _("Provide information about all known Ada tasks")); add_cmd ("task", class_run, task_command, _("Use this command to switch between Ada tasks.\n\ Without argument, this command simply prints the current task ID"), &cmdlist); }