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[/] [or1k/] [trunk/] [gdb-5.3/] [gdb/] [uw-thread.c] - Rev 1773
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/* Low level interface for debugging UnixWare user-mode threads for GDB, the GNU debugger. Copyright 1999, 2000, 2001 Free Software Foundation, Inc. Written by Nick Duffek <nsd@cygnus.com>. 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 2 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, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Like many systems, UnixWare implements two classes of threads: kernel-mode threads, which are scheduled by the kernel; and user-mode threads, which are scheduled by a library. UnixWare calls these two classes lightweight processes (LWPs) and threads, respectively. This module deals with user-mode threads. It calls procfs_ops functions to deal with LWPs and processes and core_ops functions to deal with core files. As of this writing, the user-mode thread debugging interface is not documented beyond the comments in <thread.h>. The following description has been gleaned from experience and from information provided by SCO. libthread.so, against which all UnixWare user-mode thread programs link, provides a global thread_debug structure named _thr_debug. It has three fields: (1) thr_map is a pointer to a pointer to an element of a thread_map ring. A thread_map contains a single thread's id number, state, LWP pointer, recent register state, and other useful information. (2) thr_brk is a pointer to a stub function that libthread.so calls when it changes a thread's state, e.g. by creating it, switching it to an LWP, or causing it to exit. (3) thr_debug_on controls whether libthread.so calls thr_brk(). Debuggers are able to track thread activity by setting a private breakpoint on thr_brk() and setting thr_debug_on to 1. thr_brk() receives two arguments: (1) a pointer to a thread_map describing the thread being changed; and (2) an enum thread_change specifying one of the following changes: invalid unknown thread_create thread has just been created thread_exit thread has just exited switch_begin thread will be switched to an LWP switch_complete thread has been switched to an LWP cancel_complete thread wasn't switched to an LWP thread_suspend thread has been thr_suspend()ed thread_suspend_pending thread will be thr_suspend()ed thread_continue thread has been thr_continue()d The thread_map argument to thr_brk() is NULL under the following circumstances: - The main thread is being acted upon. The main thread always has id 1, so its thread_map is easy to find by scanning through _thr_debug.thr_map. - A "switch_complete" change is occurring, which means that the thread specified in the most recent "switch_begin" change has moved to an LWP. - A "cancel_complete" change is occurring, which means that the thread specified in the most recent "switch_begin" change has not moved to an LWP after all. - A spurious "switch_begin" change is occurring after a "thread_exit" change. Between switch_begin and switch_complete or cancel_complete, the affected thread's LWP pointer is not reliable. It is possible that other parts of the thread's thread_map are also unreliable during that time. */ #include "defs.h" #include "gdbthread.h" #include "target.h" #include "inferior.h" #include "regcache.h" #include <fcntl.h> /* <thread.h> includes <sys/priocntl.h>, which requires boolean_t from <sys/types.h>, which doesn't typedef boolean_t with gcc. */ #define boolean_t int #include <thread.h> #undef boolean_t #include <synch.h> /* for UnixWare 2.x */ /* Prototypes for supply_gregset etc. */ #include "gregset.h" /* Offset from SP to first arg on stack at first instruction of a function. We provide a default here that's right for most, if not all, targets that use this file. */ #ifndef SP_ARG0 #define SP_ARG0 (1 * 4) #endif /* Whether to emit debugging output. */ #define DEBUG 0 /* Default debugging output file, overridden by envvar UWTHR_DEBUG. */ #define DEBUG_FILE "/dev/tty" /* #if DEBUG, write string S to the debugging output channel. */ #if !DEBUG # define DBG(fmt_and_args) # define DBG2(fmt_and_args) #else # define DBG(fmt_and_args) dbg fmt_and_args # define DBG2(fmt_and_args) #endif /* Back end to CALL_BASE() and TRY_BASE(): evaluate CALL, then convert inferior_ptid to a composite thread/process id. */ #define CALL_BASE_1(call) \ do { \ DBG2(("CALL_BASE(" #call ")")); \ call; \ do_cleanups (infpid_cleanup); \ } while (0) /* If inferior_ptid can be converted to a composite lwp/process id, do so, evaluate base_ops function CALL, and then convert inferior_ptid back to a composite thread/process id. Otherwise, issue an error message and return nonlocally. */ #define CALL_BASE(call) \ do { \ if (!lwp_infpid ()) \ error ("uw-thread: no lwp"); \ CALL_BASE_1 (call); \ } while (0) /* Like CALL_BASE(), but instead of returning nonlocally on error, set *CALLED to whether the inferior_ptid conversion was successful. */ #define TRY_BASE(call, called) \ do { \ if ((*(called) = lwp_infpid ())) \ CALL_BASE_1 (call); \ } while (0) /* Information passed by thread_iter() to its callback parameter. */ typedef struct { struct thread_map map; __lwp_desc_t lwp; CORE_ADDR mapp; } iter_t; /* Private thread data for the thread_info struct. */ struct private_thread_info { int stable; /* 0 if libthread.so is modifying thread map */ int thrid; /* thread id assigned by libthread.so */ int lwpid; /* thread's lwp if .stable, 0 means no lwp */ CORE_ADDR mapp; /* address of thread's map structure */ }; /* procfs.c's target-specific operations. */ extern struct target_ops procfs_ops; /* Flag to prevent procfs.c from starting inferior processes. */ extern int procfs_suppress_run; /* This module's target-specific operations. */ static struct target_ops uw_thread_ops; /* Copy of the target over which uw_thread_ops is pushed. This is more convenient than a pointer to procfs_ops or core_ops, because they lack current_target's default callbacks. */ static struct target_ops base_ops; /* Saved pointer to previous owner of target_new_objfile_hook. */ static void (*target_new_objfile_chain)(struct objfile *); /* Whether we are debugging a user-space thread program. This isn't set until after libthread.so is loaded by the program being debugged. Except for module one-time intialization and where otherwise documented, no functions in this module get called when !uw_thread_active. */ static int uw_thread_active; /* For efficiency, cache the addresses of libthread.so's _thr_debug structure, its thr_brk stub function, and the main thread's map. */ static CORE_ADDR thr_debug_addr; static CORE_ADDR thr_brk_addr; static CORE_ADDR thr_map_main; /* Remember the thread most recently marked as switching. Necessary because libthread.so passes null map when calling stub with tc_*_complete. */ static struct thread_info *switchto_thread; /* Cleanup chain for safely restoring inferior_ptid after CALL_BASE. */ static struct cleanup *infpid_cleanup; #if DEBUG /* Helper function for DBG() macro: if printf-style FMT is non-null, format it with args and display the result on the debugging output channel. */ static void dbg (char *fmt, ...) { static int fd = -1, len; va_list args; char buf[1024]; char *path; if (!fmt) return; if (fd < 0) { path = getenv ("UWTHR_DEBUG"); if (!path) path = DEBUG_FILE; if ((fd = open (path, O_WRONLY | O_CREAT | O_TRUNC, 0664)) < 0) error ("can't open %s\n", path); } va_start (args, fmt); vsprintf (buf, fmt, args); va_end (args); len = strlen (buf); buf[len] = '\n'; (void)write (fd, buf, len + 1); } #if 0 /* Return a string representing composite PID's components. */ static char * dbgpid (ptid_t ptid) { static char *buf, buf1[80], buf2[80]; if (!buf || buf == buf2) buf = buf1; else buf = buf2; if (PIDGET (ptid) <= 0) sprintf (buf, "%d", PIDGET (ptid)); else sprintf (buf, "%s %ld/%d", ISTID (pid) ? "thr" : "lwp", TIDGET (pid), PIDGET (pid)); return buf; } /* Return a string representing thread state CHANGE. */ static char * dbgchange (enum thread_change change) { switch (change) { case tc_invalid: return "invalid"; case tc_thread_create: return "thread_create"; case tc_thread_exit: return "thread_exit"; case tc_switch_begin: return "switch_begin"; case tc_switch_complete: return "switch_complete"; case tc_cancel_complete: return "cancel_complete"; case tc_thread_suspend: return "thread_suspend"; case tc_thread_suspend_pending: return "thread_suspend_pending"; case tc_thread_continue: return "thread_continue"; default: return "unknown"; } } /* Return a string representing thread STATE. */ static char * dbgstate (int state) { switch (state) { case TS_ONPROC: return "running"; case TS_SLEEP: return "sleeping"; case TS_RUNNABLE: return "runnable"; case TS_ZOMBIE: return "zombie"; case TS_SUSPENDED: return "suspended"; #ifdef TS_FORK case TS_FORK: return "forking"; #endif default: return "confused"; } } #endif /* 0 */ #endif /* DEBUG */ /* Read the contents of _thr_debug into *DEBUGP. Return success. */ static int read_thr_debug (struct thread_debug *debugp) { return base_ops.to_xfer_memory (thr_debug_addr, (char *)debugp, sizeof (*debugp), 0, NULL, &base_ops); } /* Read into MAP the contents of the thread map at inferior process address MAPP. Return success. */ static int read_map (CORE_ADDR mapp, struct thread_map *map) { return base_ops.to_xfer_memory ((CORE_ADDR)THR_MAP (mapp), (char *)map, sizeof (*map), 0, NULL, &base_ops); } /* Read into LWP the contents of the lwp decriptor at inferior process address LWPP. Return success. */ static int read_lwp (CORE_ADDR lwpp, __lwp_desc_t *lwp) { return base_ops.to_xfer_memory (lwpp, (char *)lwp, sizeof (*lwp), 0, NULL, &base_ops); } /* Iterate through all user threads, applying FUNC(<map>, <lwp>, DATA) until (a) FUNC returns nonzero, (b) FUNC has been applied to all threads, or (c) an error occurs, where <map> is the thread's struct thread_map and <lwp> if non-null is the thread's current __lwp_desc_t. If a call to FUNC returns nonzero, return that value; otherwise, return 0. */ static int thread_iter (int (*func)(iter_t *, void *), void *data) { struct thread_debug debug; CORE_ADDR first, mapp; iter_t iter; int ret; if (!read_thr_debug (&debug)) return 0; if (!base_ops.to_xfer_memory ((CORE_ADDR)debug.thr_map, (char *)&mapp, sizeof (mapp), 0, NULL, &base_ops)) return 0; if (!mapp) return 0; for (first = mapp;;) { if (!read_map (mapp, &iter.map)) return 0; if (iter.map.thr_lwpp) if (!read_lwp ((CORE_ADDR)iter.map.thr_lwpp, &iter.lwp)) return 0; iter.mapp = mapp; if ((ret = func (&iter, data))) return ret; mapp = (CORE_ADDR)iter.map.thr_next; if (mapp == first) return 0; } } /* Deactivate user-mode thread support. */ static void deactivate_uw_thread (void) { remove_thread_event_breakpoints (); uw_thread_active = 0; unpush_target (&uw_thread_ops); } /* Return the composite lwp/process id corresponding to composite id PID. If PID is a thread with no lwp, return 0. */ static ptid_t thr_to_lwp (ptid_t ptid) { struct thread_info *info; ptid_t lid; if (!ISTID (ptid)) lid = ptid; else if (!(info = find_thread_pid (ptid))) lid = null_ptid; else if (!info->private->lwpid) lid = null_ptid; else lid = MKLID (PIDGET (ptid), info->private->lwpid); DBG2((" thr_to_lwp(%s) = %s", dbgpid (pid), dbgpid (lid))); return lid; } /* find_thread_lwp() callback: return whether TP describes a thread associated with lwp id DATA. */ static int find_thread_lwp_callback (struct thread_info *tp, void *data) { int lwpid = (int)data; if (!ISTID (tp->ptid)) return 0; if (!tp->private->stable) return 0; if (lwpid != tp->private->lwpid) return 0; /* match */ return 1; } /* If a thread is associated with lwp id LWPID, return the corresponding member of the global thread list; otherwise, return null. */ static struct thread_info * find_thread_lwp (int lwpid) { return iterate_over_threads (find_thread_lwp_callback, (void *)lwpid); } /* Return the composite thread/process id corresponding to composite id PID. If PID is an lwp with no thread, return PID. */ static ptid_t lwp_to_thr (ptid_t ptid) { struct thread_info *info; int lwpid; ptid_t tid = ptid; if (ISTID (ptid)) goto done; if (!(lwpid = LIDGET (ptid))) goto done; if (!(info = find_thread_lwp (lwpid))) goto done; tid = MKTID (PIDGET (ptid), info->private->thrid); done: DBG2((ISTID (tid) ? NULL : "lwp_to_thr: no thr for %s", dbgpid (ptid))); return tid; } /* do_cleanups() callback: convert inferior_ptid to a composite thread/process id after having made a procfs call. */ static void thr_infpid (void *unused) { ptid_t ptid = lwp_to_thr (inferior_ptid); DBG2((" inferior_ptid from procfs: %s => %s", dbgpid (inferior_ptid), dbgpid (ptid))); inferior_ptid = ptid; } /* If possible, convert inferior_ptid to a composite lwp/process id in preparation for making a procfs call. Return success. */ static int lwp_infpid (void) { ptid_t ptid = thr_to_lwp (inferior_ptid); DBG2((" inferior_ptid to procfs: %s => %s", dbgpid (inferior_ptid), dbgpid (ptid))); if (ptid_equal (ptid, null_ptid)) return 0; inferior_ptid = ptid; infpid_cleanup = make_cleanup (thr_infpid, NULL); return 1; } /* Add to the global thread list a new user-mode thread with system id THRID, lwp id LWPID, map address MAPP, and composite thread/process PID. */ static void add_thread_uw (int thrid, int lwpid, CORE_ADDR mapp, ptid_t ptid) { struct thread_info *newthread; if ((newthread = add_thread (ptid)) == NULL) error ("failed to create new thread structure"); newthread->private = xmalloc (sizeof (struct private_thread_info)); newthread->private->stable = 1; newthread->private->thrid = thrid; newthread->private->lwpid = lwpid; newthread->private->mapp = mapp; if (target_has_execution) printf_unfiltered ("[New %s]\n", target_pid_to_str (ptid)); } /* notice_threads() and find_main() callback: if the thread list doesn't already contain the thread described by ITER, add it if it's the main thread or if !DATA. */ static int notice_thread (iter_t *iter, void *data) { int thrid = iter->map.thr_tid; int lwpid = !iter->map.thr_lwpp ? 0 : iter->lwp.lwp_id; ptid_t ptid = MKTID (PIDGET (inferior_ptid), thrid); if (!find_thread_pid (ptid) && (!data || thrid == 1)) add_thread_uw (thrid, lwpid, iter->mapp, ptid); return 0; } /* Add to the thread list any threads it doesn't already contain. */ static void notice_threads (void) { thread_iter (notice_thread, NULL); } /* Return the address of the main thread's map. On error, return 0. */ static CORE_ADDR find_main (void) { if (!thr_map_main) { struct thread_info *info; thread_iter (notice_thread, (void *)1); if ((info = find_thread_pid (MKTID (PIDGET (inferior_ptid), 1)))) thr_map_main = info->private->mapp; } return thr_map_main; } /* Attach to process specified by ARGS, then initialize for debugging it and wait for the trace-trap that results from attaching. This function only gets called with uw_thread_active == 0. */ static void uw_thread_attach (char *args, int from_tty) { procfs_ops.to_attach (args, from_tty); if (uw_thread_active) thr_infpid (NULL); } /* Detach from the process attached to by uw_thread_attach(). */ static void uw_thread_detach (char *args, int from_tty) { deactivate_uw_thread (); base_ops.to_detach (args, from_tty); } /* Tell the inferior process to continue running thread PID if >= 0 and all threads otherwise. */ static void uw_thread_resume (ptid_t ptid, int step, enum target_signal signo) { if (PIDGET (ptid) > 0) { ptid = thr_to_lwp (ptid); if (ptid_equal (ptid, null_ptid)) ptid = pid_to_ptid (-1); } CALL_BASE (base_ops.to_resume (ptid, step, signo)); } /* If the trap we just received from lwp PID was due to a breakpoint on the libthread.so debugging stub, update this module's state accordingly. */ static void libthread_stub (ptid_t ptid) { CORE_ADDR sp, mapp, mapp_main; enum thread_change change; struct thread_map map; __lwp_desc_t lwp; int lwpid; ptid_t tid = null_ptid; struct thread_info *info; /* Check for stub breakpoint. */ if (read_pc_pid (ptid) - DECR_PC_AFTER_BREAK != thr_brk_addr) return; /* Retrieve stub args. */ sp = read_register_pid (SP_REGNUM, ptid); if (!base_ops.to_xfer_memory (sp + SP_ARG0, (char *)&mapp, sizeof (mapp), 0, NULL, &base_ops)) goto err; if (!base_ops.to_xfer_memory (sp + SP_ARG0 + sizeof (mapp), (char *)&change, sizeof (change), 0, NULL, &base_ops)) goto err; /* create_inferior() may not have finished yet, so notice the main thread to ensure that it's displayed first by add_thread(). */ mapp_main = find_main (); /* Notice thread creation, deletion, or stability change. */ switch (change) { case tc_switch_begin: if (!mapp) /* usually means main thread */ mapp = mapp_main; /* fall through */ case tc_thread_create: case tc_thread_exit: if (!mapp) break; if (!read_map (mapp, &map)) goto err; tid = MKTID (PIDGET (ptid), map.thr_tid); switch (change) { case tc_thread_create: /* new thread */ if (!map.thr_lwpp) lwpid = 0; else if (!read_lwp ((CORE_ADDR)map.thr_lwpp, &lwp)) goto err; else lwpid = lwp.lwp_id; add_thread_uw (map.thr_tid, lwpid, mapp, tid); break; case tc_thread_exit: /* thread has exited */ printf_unfiltered ("[Exited %s]\n", target_pid_to_str (tid)); delete_thread (tid); if (ptid_equal (tid, inferior_ptid)) inferior_ptid = ptid; break; case tc_switch_begin: /* lwp is switching threads */ if (switchto_thread) goto err; if (!(switchto_thread = find_thread_pid (tid))) goto err; switchto_thread->private->stable = 0; break; default: break; } break; case tc_switch_complete: /* lwp has switched threads */ case tc_cancel_complete: /* lwp didn't switch threads */ if (!switchto_thread) goto err; if (change == tc_switch_complete) { /* If switchto_thread is the main thread, then (a) the corresponding tc_switch_begin probably received a null map argument and therefore (b) it may have been a spurious switch following a tc_thread_exit. Therefore, explicitly query the thread's lwp before caching it in its thread list entry. */ if (!read_map (switchto_thread->private->mapp, &map)) goto err; if (map.thr_lwpp) { if (!read_lwp ((CORE_ADDR)map.thr_lwpp, &lwp)) goto err; if ((info = find_thread_lwp (lwp.lwp_id))) info->private->lwpid = 0; switchto_thread->private->lwpid = lwp.lwp_id; } } switchto_thread->private->stable = 1; switchto_thread = NULL; break; case tc_invalid: case tc_thread_suspend: case tc_thread_suspend_pending: case tc_thread_continue: err: DBG(("unexpected condition in libthread_stub()")); break; } DBG2(("libthread_stub(%s): %s %s %s", dbgpid (pid), dbgpid (tid), dbgchange (change), tid ? dbgstate (map.thr_state) : "")); } /* Wait for thread/lwp/process ID if >= 0 or for any thread otherwise. */ static ptid_t uw_thread_wait (ptid_t ptid, struct target_waitstatus *status) { if (PIDGET (ptid) > 0) ptid = thr_to_lwp (ptid); if (PIDGET (ptid) <= 0) ptid = pid_to_ptid (-1); CALL_BASE (ptid = base_ops.to_wait (ptid, status)); if (status->kind == TARGET_WAITKIND_STOPPED && status->value.sig == TARGET_SIGNAL_TRAP) libthread_stub (ptid); return lwp_to_thr (ptid); } /* Tell gdb about the registers in the thread/lwp/process specified by inferior_ptid. */ static void uw_thread_fetch_registers (int regno) { int called; struct thread_info *info; struct thread_map map; TRY_BASE (base_ops.to_fetch_registers (regno), &called); if (called) return; if (!(info = find_thread_pid (inferior_ptid))) return; if (!read_map (info->private->mapp, &map)) return; supply_gregset (&map.thr_ucontext.uc_mcontext.gregs); supply_fpregset (&map.thr_ucontext.uc_mcontext.fpregs); } /* Store gdb's current view of the register set into the thread/lwp/process specified by inferior_ptid. */ static void uw_thread_store_registers (int regno) { CALL_BASE (base_ops.to_store_registers (regno)); } /* Prepare to modify the registers array. */ static void uw_thread_prepare_to_store (void) { CALL_BASE (base_ops.to_prepare_to_store ()); } /* Fork an inferior process and start debugging it. This function only gets called with uw_thread_active == 0. */ static void uw_thread_create_inferior (char *exec_file, char *allargs, char **env) { if (uw_thread_active) deactivate_uw_thread (); procfs_ops.to_create_inferior (exec_file, allargs, env); if (uw_thread_active) { find_main (); thr_infpid (NULL); } } /* Kill and forget about the inferior process. */ static void uw_thread_kill (void) { base_ops.to_kill (); } /* Clean up after the inferior exits. */ static void uw_thread_mourn_inferior (void) { deactivate_uw_thread (); base_ops.to_mourn_inferior (); } /* Return whether this module can attach to and run processes. This function only gets called with uw_thread_active == 0. */ static int uw_thread_can_run (void) { return procfs_suppress_run; } /* Return whether thread PID is still valid. */ static int uw_thread_alive (ptid_t ptid) { if (!ISTID (ptid)) return base_ops.to_thread_alive (ptid); /* If it's in the thread list, it's valid, because otherwise libthread_stub() would have deleted it. */ return in_thread_list (ptid); } /* Add to the thread list any threads and lwps it doesn't already contain. */ static void uw_thread_find_new_threads (void) { CALL_BASE (if (base_ops.to_find_new_threads) base_ops.to_find_new_threads ()); notice_threads (); } /* Return a string for pretty-printing PID in "info threads" output. This may be called by either procfs.c or by generic gdb. */ static char * uw_thread_pid_to_str (ptid_t ptid) { #define FMT "Thread %ld" static char buf[sizeof (FMT) + 3 * sizeof (long)]; if (!ISTID (ptid)) /* core_ops says "process foo", so call procfs_ops explicitly. */ return procfs_ops.to_pid_to_str (ptid); sprintf (buf, FMT, TIDGET (ptid)); #undef FMT return buf; } /* Return a string displaying INFO state information in "info threads" output. */ static char * uw_extra_thread_info (struct thread_info *info) { static char buf[80]; struct thread_map map; __lwp_desc_t lwp; int lwpid; char *name; if (!ISTID (info->ptid)) return NULL; if (!info->private->stable) return "switching"; if (!read_map (info->private->mapp, &map)) return NULL; if (!map.thr_lwpp || !read_lwp ((CORE_ADDR)map.thr_lwpp, &lwp)) lwpid = 0; else lwpid = lwp.lwp_id; switch (map.thr_state) { case TS_ONPROC: name = "running"; break; case TS_SLEEP: name = "sleeping"; break; case TS_RUNNABLE: name = "runnable"; break; case TS_ZOMBIE: name = "zombie"; break; case TS_SUSPENDED: name = "suspended"; break; #ifdef TS_FORK case TS_FORK: name = "forking"; break; #endif default: name = "confused"; break; } if (!lwpid) return name; sprintf (buf, "%s, LWP %d", name, lwpid); return buf; } /* Check whether libthread.so has just been loaded, and if so, try to initialize user-space thread debugging support. libthread.so loading happens while (a) an inferior process is being started by procfs and (b) a core image is being loaded. This function often gets called with uw_thread_active == 0. */ static void libthread_init (void) { struct minimal_symbol *ms; struct thread_debug debug; CORE_ADDR onp; struct breakpoint *b; int one = 1; /* Don't initialize twice. */ if (uw_thread_active) return; /* Check whether libthread.so has been loaded. */ if (!(ms = lookup_minimal_symbol ("_thr_debug", NULL, NULL))) return; /* Cache _thr_debug's address. */ if (!(thr_debug_addr = SYMBOL_VALUE_ADDRESS (ms))) return; /* Initialize base_ops.to_xfer_memory(). */ base_ops = current_target; /* Load _thr_debug's current contents. */ if (!read_thr_debug (&debug)) return; /* User code (e.g. my test programs) may dereference _thr_debug, making it availble to GDB before shared libs are loaded. */ if (!debug.thr_map) return; /* libthread.so has been loaded, and the current_target should now reflect core_ops or procfs_ops. */ push_target (&uw_thread_ops); /* must precede notice_threads() */ uw_thread_active = 1; if (!target_has_execution) /* Locate threads in core file. */ notice_threads (); else { /* Set a breakpoint on the stub function provided by libthread.so. */ thr_brk_addr = (CORE_ADDR)debug.thr_brk; if (!(b = create_thread_event_breakpoint (thr_brk_addr))) goto err; /* Activate the stub function. */ onp = (CORE_ADDR)&((struct thread_debug *)thr_debug_addr)->thr_debug_on; if (!base_ops.to_xfer_memory ((CORE_ADDR)onp, (char *)&one, sizeof (one), 1, NULL, &base_ops)) { delete_breakpoint (b); goto err; } /* Prepare for finding the main thread, which doesn't yet exist. */ thr_map_main = 0; } return; err: warning ("uw-thread: unable to initialize user-mode thread debugging\n"); deactivate_uw_thread (); } /* target_new_objfile_hook callback. If OBJFILE is non-null, check whether libthread.so was just loaded, and if so, prepare for user-mode thread debugging. If OBJFILE is null, libthread.so has gone away, so stop debugging user-mode threads. This function often gets called with uw_thread_active == 0. */ static void uw_thread_new_objfile (struct objfile *objfile) { if (objfile) libthread_init (); else if (uw_thread_active) deactivate_uw_thread (); if (target_new_objfile_chain) target_new_objfile_chain (objfile); } /* Initialize uw_thread_ops. */ static void init_uw_thread_ops (void) { uw_thread_ops.to_shortname = "unixware-threads"; uw_thread_ops.to_longname = "UnixWare threads and pthread."; uw_thread_ops.to_doc = "UnixWare threads and pthread support."; uw_thread_ops.to_attach = uw_thread_attach; uw_thread_ops.to_detach = uw_thread_detach; uw_thread_ops.to_resume = uw_thread_resume; uw_thread_ops.to_wait = uw_thread_wait; uw_thread_ops.to_fetch_registers = uw_thread_fetch_registers; uw_thread_ops.to_store_registers = uw_thread_store_registers; uw_thread_ops.to_prepare_to_store = uw_thread_prepare_to_store; uw_thread_ops.to_create_inferior = uw_thread_create_inferior; uw_thread_ops.to_kill = uw_thread_kill; uw_thread_ops.to_mourn_inferior = uw_thread_mourn_inferior; uw_thread_ops.to_can_run = uw_thread_can_run; uw_thread_ops.to_thread_alive = uw_thread_alive; uw_thread_ops.to_find_new_threads = uw_thread_find_new_threads; uw_thread_ops.to_pid_to_str = uw_thread_pid_to_str; uw_thread_ops.to_extra_thread_info = uw_extra_thread_info; uw_thread_ops.to_stratum = thread_stratum; uw_thread_ops.to_magic = OPS_MAGIC; } /* Module startup initialization function, automagically called by init.c. */ void _initialize_uw_thread (void) { init_uw_thread_ops (); add_target (&uw_thread_ops); procfs_suppress_run = 1; /* Notice when libthread.so gets loaded. */ target_new_objfile_chain = target_new_objfile_hook; target_new_objfile_hook = uw_thread_new_objfile; }
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