| /* Multi-threaded debugging support for the thread_db interface, |
| used on operating systems such as Solaris and Linux. |
| Copyright 1999, 2000, 2001 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 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. */ |
| |
| /* This module implements a thread_stratum target that sits on top of |
| a normal process_stratum target (such as procfs or ptrace). The |
| process_stratum target must install this thread_stratum target when |
| it detects the presence of the thread_db shared library. |
| |
| This module will then use the thread_db API to add thread-awareness |
| to the functionality provided by the process_stratum target (or in |
| some cases, to add user-level thread awareness on top of the |
| kernel-level thread awareness that is already provided by the |
| process_stratum target). |
| |
| Solaris threads (for instance) are a multi-level thread implementation; |
| the kernel provides a Light Weight Process (LWP) which the procfs |
| process_stratum module is aware of. This module must then mediate |
| the relationship between kernel LWP threads and user (eg. posix) |
| threads. |
| |
| Linux threads are likely to be different -- but the thread_db |
| library API should make the difference largely transparent to GDB. |
| |
| */ |
| |
| /* The thread_db API provides a number of functions that give the caller |
| access to the inner workings of the child process's thread library. |
| We will be using the following (others may be added): |
| |
| td_thr_validate Confirm valid "live" thread |
| td_thr_get_info Get info about a thread |
| td_thr_getgregs Get thread's general registers |
| td_thr_getfpregs Get thread's floating point registers |
| td_thr_setgregs Set thread's general registers |
| td_thr_setfpregs Set thread's floating point registers |
| td_ta_map_id2thr Get thread handle from thread id |
| td_ta_map_lwp2thr Get thread handle from LWP id |
| td_ta_thr_iter Iterate over all threads (with callback) |
| |
| In return, the debugger has to provide certain services to the |
| thread_db library. Some of these aren't actually required to do |
| anything in practice. For instance, the thread_db expects to be |
| able to stop the child process and start it again: but in our |
| context, the child process will always be stopped already when we |
| invoke the thread_db library, so the functions that we provide for |
| the library to stop and start the child process are no-ops. |
| |
| Here is the list of functions which we export to the thread_db |
| library, divided into no-op functions vs. functions that actually |
| have to do something: |
| |
| No-op functions: |
| |
| ps_pstop Stop the child process |
| ps_pcontinue Continue the child process |
| ps_lstop Stop a specific LWP (kernel thread) |
| ps_lcontinue Continue an LWP |
| ps_lgetxregsize Get size of LWP's xregs (sparc) |
| ps_lgetxregs Get LWP's xregs (sparc) |
| ps_lsetxregs Set LWP's xregs (sparc) |
| |
| Functions that have to do useful work: |
| |
| ps_pglobal_lookup Get the address of a global symbol |
| ps_pdread Read memory, data segment |
| ps_ptread Read memory, text segment |
| ps_pdwrite Write memory, data segment |
| ps_ptwrite Write memory, text segment |
| ps_lgetregs Get LWP's general registers |
| ps_lgetfpregs Get LWP's floating point registers |
| ps_lsetregs Set LWP's general registers |
| ps_lsetfpregs Set LWP's floating point registers |
| ps_lgetLDT Get LWP's Local Descriptor Table (x86) |
| |
| Thus, if we ask the thread_db library to give us the general registers |
| for user thread X, thread_db may figure out that user thread X is |
| actually mapped onto kernel thread Y. Thread_db does not know how |
| to obtain the registers for kernel thread Y, but GDB does, so thread_db |
| turns the request right back to us via the ps_lgetregs callback. */ |
| |
| #include "defs.h" |
| #include "gdbthread.h" |
| #include "target.h" |
| #include "inferior.h" |
| #include "gdbcmd.h" |
| #include "regcache.h" |
| |
| #include "gdb_wait.h" |
| |
| #include <time.h> |
| |
| #if defined(USE_PROC_FS) || defined(HAVE_GREGSET_T) |
| #include <sys/procfs.h> |
| #endif |
| |
| #include "gdb_proc_service.h" |
| |
| #if defined HAVE_STDINT_H /* Pre-5.2 systems don't have this header */ |
| #if defined (HAVE_THREAD_DB_H) |
| #include <thread_db.h> /* defines outgoing API (td_thr_* calls) */ |
| #else |
| #include "gdb_thread_db.h" |
| #endif |
| |
| #include <dlfcn.h> /* dynamic library interface */ |
| |
| /* Prototypes for supply_gregset etc. */ |
| #include "gregset.h" |
| |
| #ifndef TIDGET |
| #define TIDGET(PID) (((PID) & 0x7fffffff) >> 16) |
| #define PIDGET(PID) (((PID) & 0xffff)) |
| #define MERGEPID(PID, TID) (((PID) & 0xffff) | ((TID) << 16)) |
| #endif |
| |
| /* Macros for superimposing PID and TID into inferior_pid. */ |
| #define THREAD_FLAG 0x80000000 |
| #define is_thread(ARG) (((ARG) & THREAD_FLAG) != 0) |
| #define is_lwp(ARG) (((ARG) & THREAD_FLAG) == 0) |
| #define GET_LWP(PID) TIDGET (PID) |
| #define GET_THREAD(PID) TIDGET (PID) |
| #define BUILD_LWP(TID, PID) MERGEPID (PID, TID) |
| #define BUILD_THREAD(TID, PID) (MERGEPID (PID, TID) | THREAD_FLAG) |
| |
| /* |
| * target_beneath is a pointer to the target_ops underlying this one. |
| */ |
| |
| static struct target_ops *target_beneath; |
| |
| |
| /* |
| * target vector defined in this module: |
| */ |
| |
| static struct target_ops thread_db_ops; |
| |
| /* |
| * Typedefs required to resolve differences between the thread_db |
| * and proc_service API defined on different versions of Solaris: |
| */ |
| |
| #if defined(PROC_SERVICE_IS_OLD) |
| typedef const struct ps_prochandle *gdb_ps_prochandle_t; |
| typedef char *gdb_ps_read_buf_t; |
| typedef char *gdb_ps_write_buf_t; |
| typedef int gdb_ps_size_t; |
| #else |
| typedef struct ps_prochandle *gdb_ps_prochandle_t; |
| typedef void *gdb_ps_read_buf_t; |
| typedef const void *gdb_ps_write_buf_t; |
| typedef size_t gdb_ps_size_t; |
| #endif |
| |
| /* |
| * proc_service callback functions, called by thread_db. |
| */ |
| |
| ps_err_e |
| ps_pstop (gdb_ps_prochandle_t ph) /* Process stop */ |
| { |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_pcontinue (gdb_ps_prochandle_t ph) /* Process continue */ |
| { |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lstop (gdb_ps_prochandle_t ph, /* LWP stop */ |
| lwpid_t lwpid) |
| { |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lcontinue (gdb_ps_prochandle_t ph, /* LWP continue */ |
| lwpid_t lwpid) |
| { |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lgetxregsize (gdb_ps_prochandle_t ph, /* Get XREG size */ |
| lwpid_t lwpid, |
| int *xregsize) |
| { |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lgetxregs (gdb_ps_prochandle_t ph, /* Get XREGS */ |
| lwpid_t lwpid, |
| caddr_t xregset) |
| { |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lsetxregs (gdb_ps_prochandle_t ph, /* Set XREGS */ |
| lwpid_t lwpid, |
| caddr_t xregset) |
| { |
| return PS_OK; |
| } |
| |
| void |
| ps_plog (const char *fmt, ...) |
| { |
| va_list args; |
| |
| va_start (args, fmt); |
| vfprintf_filtered (gdb_stderr, fmt, args); |
| } |
| |
| /* Look up a symbol in GDB's global symbol table. |
| Return the symbol's address. |
| FIXME: it would be more correct to look up the symbol in the context |
| of the LD_OBJECT_NAME provided. However we're probably fairly safe |
| as long as there aren't name conflicts with other libraries. */ |
| |
| ps_err_e |
| ps_pglobal_lookup (gdb_ps_prochandle_t ph, |
| const char *ld_object_name, /* the library name */ |
| const char *ld_symbol_name, /* the symbol name */ |
| paddr_t *ld_symbol_addr) /* return the symbol addr */ |
| { |
| struct minimal_symbol *ms; |
| |
| ms = lookup_minimal_symbol (ld_symbol_name, NULL, NULL); |
| |
| if (!ms) |
| return PS_NOSYM; |
| |
| *ld_symbol_addr = SYMBOL_VALUE_ADDRESS (ms); |
| |
| return PS_OK; |
| } |
| |
| /* Worker function for all memory reads and writes: */ |
| static ps_err_e rw_common (const struct ps_prochandle *ph, |
| paddr_t addr, |
| char *buf, |
| int size, |
| int write_p); |
| |
| /* target_xfer_memory direction consts */ |
| enum {PS_READ = 0, PS_WRITE = 1}; |
| |
| ps_err_e |
| ps_pdread (gdb_ps_prochandle_t ph, /* read from data segment */ |
| paddr_t addr, |
| gdb_ps_read_buf_t buf, |
| gdb_ps_size_t size) |
| { |
| return rw_common (ph, addr, buf, size, PS_READ); |
| } |
| |
| ps_err_e |
| ps_pdwrite (gdb_ps_prochandle_t ph, /* write to data segment */ |
| paddr_t addr, |
| gdb_ps_write_buf_t buf, |
| gdb_ps_size_t size) |
| { |
| return rw_common (ph, addr, (char *) buf, size, PS_WRITE); |
| } |
| |
| ps_err_e |
| ps_ptread (gdb_ps_prochandle_t ph, /* read from text segment */ |
| paddr_t addr, |
| gdb_ps_read_buf_t buf, |
| gdb_ps_size_t size) |
| { |
| return rw_common (ph, addr, buf, size, PS_READ); |
| } |
| |
| ps_err_e |
| ps_ptwrite (gdb_ps_prochandle_t ph, /* write to text segment */ |
| paddr_t addr, |
| gdb_ps_write_buf_t buf, |
| gdb_ps_size_t size) |
| { |
| return rw_common (ph, addr, (char *) buf, size, PS_WRITE); |
| } |
| |
| static struct cleanup *save_inferior_pid (void); |
| static void restore_inferior_pid (void *saved_pid); |
| static char *thr_err_string (td_err_e); |
| static char *thr_state_string (td_thr_state_e); |
| |
| struct ps_prochandle main_prochandle; |
| td_thragent_t * main_threadagent; |
| |
| /* |
| * Common proc_service routine for reading and writing memory. |
| */ |
| |
| /* FIXME: once we've munged the inferior_pid, why can't we |
| simply call target_read/write_memory and return? */ |
| |
| |
| static ps_err_e |
| rw_common (const struct ps_prochandle *ph, |
| paddr_t addr, |
| char *buf, |
| int size, |
| int write_p) |
| { |
| struct cleanup *old_chain = save_inferior_pid (); |
| int to_do = size; |
| int done = 0; |
| |
| inferior_pid = main_prochandle.pid; |
| |
| while (to_do > 0) |
| { |
| done = current_target.to_xfer_memory (addr, buf, size, write_p, |
| ¤t_target); |
| if (done <= 0) |
| { |
| if (write_p == PS_READ) |
| print_sys_errmsg ("rw_common (): read", errno); |
| else |
| print_sys_errmsg ("rw_common (): write", errno); |
| |
| return PS_ERR; |
| } |
| to_do -= done; |
| buf += done; |
| } |
| do_cleanups (old_chain); |
| return PS_OK; |
| } |
| |
| /* Cleanup functions used by the register callbacks |
| (which have to manipulate the global inferior_pid). */ |
| |
| ps_err_e |
| ps_lgetregs (gdb_ps_prochandle_t ph, /* Get LWP general regs */ |
| lwpid_t lwpid, |
| prgregset_t gregset) |
| { |
| struct cleanup *old_chain = save_inferior_pid (); |
| |
| inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| current_target.to_fetch_registers (-1); |
| |
| fill_gregset (gregset, -1); |
| do_cleanups (old_chain); |
| |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lsetregs (gdb_ps_prochandle_t ph, /* Set LWP general regs */ |
| lwpid_t lwpid, |
| const prgregset_t gregset) |
| { |
| struct cleanup *old_chain = save_inferior_pid (); |
| |
| inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| supply_gregset (gregset); |
| current_target.to_store_registers (-1); |
| do_cleanups (old_chain); |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lgetfpregs (gdb_ps_prochandle_t ph, /* Get LWP float regs */ |
| lwpid_t lwpid, |
| gdb_prfpregset_t *fpregset) |
| { |
| struct cleanup *old_chain = save_inferior_pid (); |
| |
| inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| current_target.to_fetch_registers (-1); |
| fill_fpregset (fpregset, -1); |
| do_cleanups (old_chain); |
| return PS_OK; |
| } |
| |
| ps_err_e |
| ps_lsetfpregs (gdb_ps_prochandle_t ph, /* Set LWP float regs */ |
| lwpid_t lwpid, |
| const gdb_prfpregset_t *fpregset) |
| { |
| struct cleanup *old_chain = save_inferior_pid (); |
| |
| inferior_pid = BUILD_LWP (lwpid, main_prochandle.pid); |
| supply_fpregset (fpregset); |
| current_target.to_store_registers (-1); |
| do_cleanups (old_chain); |
| return PS_OK; |
| } |
| |
| /* |
| * ps_getpid |
| * |
| * return the main pid for the child process |
| * (special for Linux -- not used on Solaris) |
| */ |
| |
| pid_t |
| ps_getpid (gdb_ps_prochandle_t ph) |
| { |
| return ph->pid; |
| } |
| |
| #ifdef TM_I386SOL2_H |
| |
| /* Reads the local descriptor table of a LWP. */ |
| |
| ps_err_e |
| ps_lgetLDT (gdb_ps_prochandle_t ph, lwpid_t lwpid, |
| struct ssd *pldt) |
| { |
| /* NOTE: only used on Solaris, therefore OK to refer to procfs.c */ |
| extern struct ssd *procfs_find_LDT_entry (int); |
| struct ssd *ret; |
| |
| ret = procfs_find_LDT_entry (BUILD_LWP (lwpid, |
| PIDGET (main_prochandle.pid))); |
| if (ret) |
| { |
| memcpy (pldt, ret, sizeof (struct ssd)); |
| return PS_OK; |
| } |
| else /* LDT not found. */ |
| return PS_ERR; |
| } |
| #endif /* TM_I386SOL2_H */ |
| |
| /* |
| * Pointers to thread_db functions: |
| * |
| * These are a dynamic library mechanism. |
| * The dlfcn.h interface will be used to initialize these |
| * so that they point to the appropriate functions in the |
| * thread_db dynamic library. This is done dynamically |
| * so that GDB can still run on systems that lack thread_db. |
| */ |
| |
| static td_err_e (*p_td_init) (void); |
| |
| static td_err_e (*p_td_ta_new) (const struct ps_prochandle *ph_p, |
| td_thragent_t **ta_pp); |
| |
| static td_err_e (*p_td_ta_delete) (td_thragent_t *ta_p); |
| |
| static td_err_e (*p_td_ta_get_nthreads) (const td_thragent_t *ta_p, |
| int *nthread_p); |
| |
| |
| static td_err_e (*p_td_ta_thr_iter) (const td_thragent_t *ta_p, |
| td_thr_iter_f *cb, |
| void *cbdata_p, |
| td_thr_state_e state, |
| int ti_pri, |
| sigset_t *ti_sigmask_p, |
| unsigned ti_user_flags); |
| |
| static td_err_e (*p_td_ta_event_addr) (const td_thragent_t *ta_p, |
| u_long event, |
| td_notify_t *notify_p); |
| |
| static td_err_e (*p_td_ta_event_getmsg) (const td_thragent_t *ta_p, |
| td_event_msg_t *msg); |
| |
| static td_err_e (*p_td_ta_set_event) (const td_thragent_t *ta_p, |
| td_thr_events_t *events); |
| |
| static td_err_e (*p_td_thr_validate) (const td_thrhandle_t *th_p); |
| |
| static td_err_e (*p_td_thr_event_enable) (const td_thrhandle_t *th_p, |
| int on_off); |
| |
| static td_err_e (*p_td_thr_get_info) (const td_thrhandle_t *th_p, |
| td_thrinfo_t *ti_p); |
| |
| static td_err_e (*p_td_thr_getgregs) (const td_thrhandle_t *th_p, |
| prgregset_t regset); |
| |
| static td_err_e (*p_td_thr_setgregs) (const td_thrhandle_t *th_p, |
| const prgregset_t regset); |
| |
| static td_err_e (*p_td_thr_getfpregs) (const td_thrhandle_t *th_p, |
| gdb_prfpregset_t *fpregset); |
| |
| static td_err_e (*p_td_thr_setfpregs) (const td_thrhandle_t *th_p, |
| const gdb_prfpregset_t *fpregset); |
| |
| static td_err_e (*p_td_ta_map_id2thr) (const td_thragent_t *ta_p, |
| thread_t tid, |
| td_thrhandle_t *th_p); |
| |
| static td_err_e (*p_td_ta_map_lwp2thr) (const td_thragent_t *ta_p, |
| lwpid_t lwpid, |
| td_thrhandle_t *th_p); |
| |
| /* |
| * API and target vector initialization function: thread_db_initialize. |
| * |
| * NOTE: this function is deliberately NOT named with the GDB convention |
| * of module initializer function names that begin with "_initialize". |
| * This module is NOT intended to be auto-initialized at GDB startup. |
| * Rather, it will only be initialized when a multi-threaded child |
| * process is detected. |
| * |
| */ |
| |
| /* |
| * Initializer for thread_db library interface. |
| * This function does the dynamic library stuff (dlopen, dlsym), |
| * and then calls the thread_db library's one-time initializer |
| * function (td_init). If everything succeeds, this function |
| * returns true; otherwise it returns false, and this module |
| * cannot be used. |
| */ |
| |
| static int |
| init_thread_db_library (void) |
| { |
| void *dlhandle; |
| td_err_e ret; |
| |
| /* Open a handle to the "thread_db" dynamic library. */ |
| if ((dlhandle = dlopen ("libthread_db.so.1", RTLD_NOW)) == NULL) |
| return 0; /* fail */ |
| |
| /* Initialize pointers to the dynamic library functions we will use. |
| * Note that we are not calling the functions here -- we are only |
| * establishing pointers to them. |
| */ |
| |
| /* td_init: initialize thread_db library. */ |
| if ((p_td_init = dlsym (dlhandle, "td_init")) == NULL) |
| return 0; /* fail */ |
| /* td_ta_new: register a target process with thread_db. */ |
| if ((p_td_ta_new = dlsym (dlhandle, "td_ta_new")) == NULL) |
| return 0; /* fail */ |
| /* td_ta_delete: un-register a target process with thread_db. */ |
| if ((p_td_ta_delete = dlsym (dlhandle, "td_ta_delete")) == NULL) |
| return 0; /* fail */ |
| |
| /* td_ta_map_id2thr: get thread handle from thread id. */ |
| if ((p_td_ta_map_id2thr = dlsym (dlhandle, "td_ta_map_id2thr")) == NULL) |
| return 0; /* fail */ |
| /* td_ta_map_lwp2thr: get thread handle from lwp id. */ |
| if ((p_td_ta_map_lwp2thr = dlsym (dlhandle, "td_ta_map_lwp2thr")) == NULL) |
| return 0; /* fail */ |
| /* td_ta_get_nthreads: get number of threads in target process. */ |
| if ((p_td_ta_get_nthreads = dlsym (dlhandle, "td_ta_get_nthreads")) == NULL) |
| return 0; /* fail */ |
| /* td_ta_thr_iter: iterate over all thread handles. */ |
| if ((p_td_ta_thr_iter = dlsym (dlhandle, "td_ta_thr_iter")) == NULL) |
| return 0; /* fail */ |
| |
| /* td_thr_validate: make sure a thread handle is real and alive. */ |
| if ((p_td_thr_validate = dlsym (dlhandle, "td_thr_validate")) == NULL) |
| return 0; /* fail */ |
| /* td_thr_get_info: get a bunch of info about a thread. */ |
| if ((p_td_thr_get_info = dlsym (dlhandle, "td_thr_get_info")) == NULL) |
| return 0; /* fail */ |
| /* td_thr_getgregs: get general registers for thread. */ |
| if ((p_td_thr_getgregs = dlsym (dlhandle, "td_thr_getgregs")) == NULL) |
| return 0; /* fail */ |
| /* td_thr_setgregs: set general registers for thread. */ |
| if ((p_td_thr_setgregs = dlsym (dlhandle, "td_thr_setgregs")) == NULL) |
| return 0; /* fail */ |
| /* td_thr_getfpregs: get floating point registers for thread. */ |
| if ((p_td_thr_getfpregs = dlsym (dlhandle, "td_thr_getfpregs")) == NULL) |
| return 0; /* fail */ |
| /* td_thr_setfpregs: set floating point registers for thread. */ |
| if ((p_td_thr_setfpregs = dlsym (dlhandle, "td_thr_setfpregs")) == NULL) |
| return 0; /* fail */ |
| |
| ret = p_td_init (); |
| if (ret != TD_OK) |
| { |
| warning ("init_thread_db: td_init: %s", thr_err_string (ret)); |
| return 0; |
| } |
| |
| /* Optional functions: |
| We can still debug even if the following functions are not found. */ |
| |
| /* td_ta_event_addr: get the breakpoint address for specified event. */ |
| p_td_ta_event_addr = dlsym (dlhandle, "td_ta_event_addr"); |
| |
| /* td_ta_event_getmsg: get the next event message for the process. */ |
| p_td_ta_event_getmsg = dlsym (dlhandle, "td_ta_event_getmsg"); |
| |
| /* td_ta_set_event: request notification of an event. */ |
| p_td_ta_set_event = dlsym (dlhandle, "td_ta_set_event"); |
| |
| /* td_thr_event_enable: enable event reporting in a thread. */ |
| p_td_thr_event_enable = dlsym (dlhandle, "td_thr_event_enable"); |
| |
| return 1; /* success */ |
| } |
| |
| /* |
| * Local utility functions: |
| */ |
| |
| |
| /* |
| |
| LOCAL FUNCTION |
| |
| save_inferior_pid - Save inferior_pid on the cleanup list |
| restore_inferior_pid - Restore inferior_pid from the cleanup list |
| |
| SYNOPSIS |
| |
| struct cleanup *save_inferior_pid (void); |
| void restore_inferior_pid (void *saved_pid); |
| |
| DESCRIPTION |
| |
| These two functions act in unison to restore inferior_pid in |
| case of an error. |
| |
| NOTES |
| |
| inferior_pid is a global variable that needs to be changed by many |
| of these routines before calling functions in procfs.c. In order |
| to guarantee that inferior_pid gets restored (in case of errors), |
| you need to call save_inferior_pid before changing it. At the end |
| of the function, you should invoke do_cleanups to restore it. |
| |
| */ |
| |
| static struct cleanup * |
| save_inferior_pid (void) |
| { |
| int *saved_pid_ptr; |
| |
| saved_pid_ptr = xmalloc (sizeof (int)); |
| *saved_pid_ptr = inferior_pid; |
| return make_cleanup (restore_inferior_pid, saved_pid_ptr); |
| } |
| |
| static void |
| restore_inferior_pid (void *arg) |
| { |
| int *saved_pid_ptr = arg; |
| inferior_pid = *saved_pid_ptr; |
| xfree (arg); |
| } |
| |
| /* |
| |
| LOCAL FUNCTION |
| |
| thr_err_string - Convert a thread_db error code to a string |
| |
| SYNOPSIS |
| |
| char * thr_err_string (errcode) |
| |
| DESCRIPTION |
| |
| Return a string description of the thread_db errcode. If errcode |
| is unknown, then return an <unknown> message. |
| |
| */ |
| |
| static char * |
| thr_err_string (td_err_e errcode) |
| { |
| static char buf[50]; |
| |
| switch (errcode) { |
| case TD_OK: return "generic 'call succeeded'"; |
| case TD_ERR: return "generic error"; |
| case TD_NOTHR: return "no thread to satisfy query"; |
| case TD_NOSV: return "no sync handle to satisfy query"; |
| case TD_NOLWP: return "no lwp to satisfy query"; |
| case TD_BADPH: return "invalid process handle"; |
| case TD_BADTH: return "invalid thread handle"; |
| case TD_BADSH: return "invalid synchronization handle"; |
| case TD_BADTA: return "invalid thread agent"; |
| case TD_BADKEY: return "invalid key"; |
| case TD_NOMSG: return "no event message for getmsg"; |
| case TD_NOFPREGS: return "FPU register set not available"; |
| case TD_NOLIBTHREAD: return "application not linked with libthread"; |
| case TD_NOEVENT: return "requested event is not supported"; |
| case TD_NOCAPAB: return "capability not available"; |
| case TD_DBERR: return "debugger service failed"; |
| case TD_NOAPLIC: return "operation not applicable to"; |
| case TD_NOTSD: return "no thread-specific data for this thread"; |
| case TD_MALLOC: return "malloc failed"; |
| case TD_PARTIALREG: return "only part of register set was written/read"; |
| case TD_NOXREGS: return "X register set not available for this thread"; |
| default: |
| sprintf (buf, "unknown thread_db error '%d'", errcode); |
| return buf; |
| } |
| } |
| |
| /* |
| |
| LOCAL FUNCTION |
| |
| thr_state_string - Convert a thread_db state code to a string |
| |
| SYNOPSIS |
| |
| char *thr_state_string (statecode) |
| |
| DESCRIPTION |
| |
| Return the thread_db state string associated with statecode. |
| If statecode is unknown, then return an <unknown> message. |
| |
| */ |
| |
| static char * |
| thr_state_string (td_thr_state_e statecode) |
| { |
| static char buf[50]; |
| |
| switch (statecode) { |
| case TD_THR_STOPPED: return "stopped by debugger"; |
| case TD_THR_RUN: return "runnable"; |
| case TD_THR_ACTIVE: return "active"; |
| case TD_THR_ZOMBIE: return "zombie"; |
| case TD_THR_SLEEP: return "sleeping"; |
| case TD_THR_STOPPED_ASLEEP: return "stopped by debugger AND blocked"; |
| default: |
| sprintf (buf, "unknown thread_db state %d", statecode); |
| return buf; |
| } |
| } |
| |
| /* |
| * Local thread/event list. |
| * This data structure will be used to hold a list of threads and |
| * pending/deliverable events. |
| */ |
| |
| typedef struct THREADINFO { |
| thread_t tid; /* thread ID */ |
| pid_t lid; /* process/lwp ID */ |
| td_thr_state_e state; /* thread state (a la thread_db) */ |
| td_thr_type_e type; /* thread type (a la thread_db) */ |
| int pending; /* true if holding a pending event */ |
| int status; /* wait status of any interesting event */ |
| } threadinfo; |
| |
| threadinfo * threadlist; |
| int threadlist_max = 0; /* current size of table */ |
| int threadlist_top = 0; /* number of threads now in table */ |
| #define THREADLIST_ALLOC 100 /* chunk size by which to expand table */ |
| |
| static threadinfo * |
| insert_thread (int tid, int lid, td_thr_state_e state, td_thr_type_e type) |
| { |
| if (threadlist_top >= threadlist_max) |
| { |
| threadlist_max += THREADLIST_ALLOC; |
| threadlist = realloc (threadlist, |
| threadlist_max * sizeof (threadinfo)); |
| if (threadlist == NULL) |
| return NULL; |
| } |
| threadlist[threadlist_top].tid = tid; |
| threadlist[threadlist_top].lid = lid; |
| threadlist[threadlist_top].state = state; |
| threadlist[threadlist_top].type = type; |
| threadlist[threadlist_top].pending = 0; |
| threadlist[threadlist_top].status = 0; |
| |
| return &threadlist[threadlist_top++]; |
| } |
| |
| static void |
| empty_threadlist (void) |
| { |
| threadlist_top = 0; |
| } |
| |
| static threadinfo * |
| next_pending_event (void) |
| { |
| int i; |
| |
| for (i = 0; i < threadlist_top; i++) |
| if (threadlist[i].pending) |
| return &threadlist[i]; |
| |
| return NULL; |
| } |
| |
| static void |
| threadlist_iter (int (*func) (), void *data, td_thr_state_e state, |
| td_thr_type_e type) |
| { |
| int i; |
| |
| for (i = 0; i < threadlist_top; i++) |
| if ((state == TD_THR_ANY_STATE || state == threadlist[i].state) && |
| (type == TD_THR_ANY_TYPE || type == threadlist[i].type)) |
| if ((*func) (&threadlist[i], data) != 0) |
| break; |
| |
| return; |
| } |
| |
| /* |
| * Global state |
| * |
| * Here we keep state information all collected in one place. |
| */ |
| |
| /* This flag is set when we activate, so that we don't do it twice. |
| Defined in linux-thread.c and used for inter-target syncronization. */ |
| extern int using_thread_db; |
| |
| /* The process id for which we've stopped. |
| * This is only set when we actually stop all threads. |
| * Otherwise it's zero. |
| */ |
| static int event_pid; |
| |
| /* |
| * The process id for a new thread to which we've just attached. |
| * This process needs special handling at resume time. |
| */ |
| static int attach_pid; |
| |
| |
| /* |
| * thread_db event handling: |
| * |
| * The mechanism for event notification via the thread_db API. |
| * These events are implemented as breakpoints. The thread_db |
| * library gives us an address where we can set a breakpoint. |
| * When the breakpoint is hit, it represents an event of interest |
| * such as: |
| * Thread creation |
| * Thread death |
| * Thread reap |
| */ |
| |
| /* Location of the thread creation event breakpoint. The code at this |
| location in the child process will be called by the pthread library |
| whenever a new thread is created. By setting a special breakpoint |
| at this location, GDB can detect when a new thread is created. We |
| obtain this location via the td_ta_event_addr call. */ |
| |
| static CORE_ADDR thread_creation_bkpt_address; |
| |
| /* Location of the thread death event breakpoint. The code at this |
| location in the child process will be called by the pthread library |
| whenever a thread is destroyed. By setting a special breakpoint at |
| this location, GDB can detect when a new thread is created. We |
| obtain this location via the td_ta_event_addr call. */ |
| |
| static CORE_ADDR thread_death_bkpt_address; |
| |
| /* This function handles the global parts of enabling thread events. |
| The thread-specific enabling is handled per-thread elsewhere. */ |
| |
| static void |
| enable_thread_event_reporting (td_thragent_t *ta) |
| { |
| td_thr_events_t events; |
| td_notify_t notify; |
| CORE_ADDR addr; |
| |
| if (p_td_ta_set_event == NULL || |
| p_td_ta_event_addr == NULL || |
| p_td_ta_event_getmsg == NULL || |
| p_td_thr_event_enable == NULL) |
| return; /* can't do thread event reporting without these funcs */ |
| |
| /* set process wide mask saying which events we are interested in */ |
| td_event_emptyset (&events); |
| td_event_addset (&events, TD_CREATE); |
| td_event_addset (&events, TD_DEATH); |
| |
| if (p_td_ta_set_event (ta, &events) != TD_OK) |
| { |
| warning ("unable to set global thread event mask"); |
| return; |
| } |
| |
| /* Delete previous thread event breakpoints, if any. */ |
| remove_thread_event_breakpoints (); |
| |
| /* create breakpoints -- thread creation and death */ |
| /* thread creation */ |
| /* get breakpoint location */ |
| if (p_td_ta_event_addr (ta, TD_CREATE, ¬ify) != TD_OK) |
| { |
| warning ("unable to get location for thread creation breakpoint"); |
| return; |
| } |
| |
| /* Set up the breakpoint. */ |
| create_thread_event_breakpoint (notify.u.bptaddr); |
| |
| /* Save it's location. */ |
| thread_creation_bkpt_address = notify.u.bptaddr; |
| |
| /* thread death */ |
| /* get breakpoint location */ |
| if (p_td_ta_event_addr (ta, TD_DEATH, ¬ify) != TD_OK) |
| { |
| warning ("unable to get location for thread death breakpoint"); |
| return; |
| } |
| /* Set up the breakpoint. */ |
| create_thread_event_breakpoint (notify.u.bptaddr); |
| |
| /* Save it's location. */ |
| thread_death_bkpt_address = notify.u.bptaddr; |
| } |
| |
| /* This function handles the global parts of disabling thread events. |
| The thread-specific enabling is handled per-thread elsewhere. */ |
| |
| static void |
| disable_thread_event_reporting (td_thragent_t *ta) |
| { |
| td_thr_events_t events; |
| |
| /* set process wide mask saying we aren't interested in any events */ |
| td_event_emptyset (&events); |
| p_td_ta_set_event (main_threadagent, &events); |
| |
| /* Delete thread event breakpoints, if any. */ |
| remove_thread_event_breakpoints (); |
| thread_creation_bkpt_address = 0; |
| thread_death_bkpt_address = 0; |
| } |
| |
| /* check_for_thread_event |
| |
| if it's a thread event we recognize (currently |
| we only recognize creation and destruction |
| events), return 1; else return 0. */ |
| |
| |
| static int |
| check_for_thread_event (struct target_waitstatus *tws, int event_pid) |
| { |
| /* FIXME: to be more efficient, we should keep a static |
| list of threads, and update it only here (with td_ta_thr_iter). */ |
| } |
| |
| static void |
| thread_db_push_target (void) |
| { |
| /* Called ONLY from thread_db_new_objfile after td_ta_new call succeeds. */ |
| |
| /* Push this target vector */ |
| push_target (&thread_db_ops); |
| /* Find the underlying process-layer target for calling later. */ |
| target_beneath = find_target_beneath (&thread_db_ops); |
| using_thread_db = 1; |
| /* Turn on thread_db event-reporting API. */ |
| enable_thread_event_reporting (main_threadagent); |
| } |
| |
| static void |
| thread_db_unpush_target (void) |
| { |
| /* Must be called whenever we remove ourself from the target stack! */ |
| |
| using_thread_db = 0; |
| target_beneath = NULL; |
| |
| /* delete local list of threads */ |
| empty_threadlist (); |
| /* Turn off the thread_db API. */ |
| p_td_ta_delete (main_threadagent); |
| /* Unpush this target vector */ |
| unpush_target (&thread_db_ops); |
| /* Reset linuxthreads module. */ |
| linuxthreads_discard_global_state (); |
| } |
| |
| /* |
| * New objfile hook function: |
| * Called for each new objfile (image, shared lib) in the target process. |
| * |
| * The purpose of this function is to detect that the target process |
| * is linked with the (appropriate) thread library. So every time a |
| * new target shared library is detected, we will call td_ta_new. |
| * If it succeeds, we know we have a multi-threaded target process |
| * that we can debug using the thread_db API. |
| */ |
| |
| /* |
| * new_objfile function: |
| * |
| * connected to target_new_objfile_hook, this function gets called |
| * every time a new binary image is loaded. |
| * |
| * At each call, we attempt to open the thread_db connection to the |
| * child process. If it succeeds, we know we have a libthread process |
| * and we can debug it with this target vector. Therefore we push |
| * ourself onto the target stack. |
| */ |
| |
| static void (*target_new_objfile_chain) (struct objfile *objfile); |
| static int stop_or_attach_thread_callback (const td_thrhandle_t *th, |
| void *data); |
| static int wait_thread_callback (const td_thrhandle_t *th, |
| void *data); |
| |
| static void |
| thread_db_new_objfile (struct objfile *objfile) |
| { |
| td_err_e ret; |
| |
| if (using_thread_db) /* libthread already detected, and */ |
| goto quit; /* thread target vector activated. */ |
| |
| if (objfile == NULL) |
| goto quit; /* un-interesting object file */ |
| |
| /* Initialize our "main prochandle" with the main inferior pid. */ |
| main_prochandle.pid = PIDGET (inferior_pid); |
| |
| /* Now attempt to open a thread_db connection to the |
| thread library running in the child process. */ |
| ret = p_td_ta_new (&main_prochandle, &main_threadagent); |
| switch (ret) { |
| default: |
| warning ("Unexpected error initializing thread_db: %s", |
| thr_err_string (ret)); |
| break; |
| case TD_NOLIBTHREAD: /* expected: no libthread in child process (yet) */ |
| break; |
| case TD_OK: /* libthread detected in child: we go live now! */ |
| thread_db_push_target (); |
| event_pid = inferior_pid; /* for resume */ |
| |
| /* Now stop everyone else, and attach any new threads you find. */ |
| p_td_ta_thr_iter (main_threadagent, |
| stop_or_attach_thread_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_LOWEST_PRIORITY, |
| TD_SIGNO_MASK, |
| TD_THR_ANY_USER_FLAGS); |
| |
| /* Now go call wait on all the threads you've stopped: |
| This allows us to absorb the SIGKILL event, and to make sure |
| that the thread knows that it is stopped (Linux peculiarity). */ |
| p_td_ta_thr_iter (main_threadagent, |
| wait_thread_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_LOWEST_PRIORITY, |
| TD_SIGNO_MASK, |
| TD_THR_ANY_USER_FLAGS); |
| |
| break; |
| } |
| quit: |
| if (target_new_objfile_chain) |
| target_new_objfile_chain (objfile); |
| } |
| |
| |
| /* |
| |
| LOCAL FUNCTION |
| |
| thread_db_alive - test thread for "aliveness" |
| |
| SYNOPSIS |
| |
| static bool thread_db_alive (int pid); |
| |
| DESCRIPTION |
| |
| returns true if thread still active in inferior. |
| |
| */ |
| |
| static int |
| thread_db_alive (int pid) |
| { |
| if (is_thread (pid)) /* user-space (non-kernel) thread */ |
| { |
| td_thrhandle_t th; |
| td_err_e ret; |
| |
| pid = GET_THREAD (pid); |
| if ((ret = p_td_ta_map_id2thr (main_threadagent, pid, &th)) != TD_OK) |
| return 0; /* thread not found */ |
| if ((ret = p_td_thr_validate (&th)) != TD_OK) |
| return 0; /* thread not valid */ |
| return 1; /* known thread: return true */ |
| } |
| else if (target_beneath->to_thread_alive) |
| return target_beneath->to_thread_alive (pid); |
| else |
| return 0; /* default to "not alive" (shouldn't happen anyway) */ |
| } |
| |
| /* |
| * get_lwp_from_thread_handle |
| */ |
| |
| static int /* lwpid_t or pid_t */ |
| get_lwp_from_thread_handle (td_thrhandle_t *th) |
| { |
| td_thrinfo_t ti; |
| td_err_e ret; |
| |
| if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| error ("get_lwp_from_thread_handle: thr_get_info failed: %s", |
| thr_err_string (ret)); |
| |
| return ti.ti_lid; |
| } |
| |
| /* |
| * get_lwp_from_thread_id |
| */ |
| |
| static int /* lwpid_t or pid_t */ |
| get_lwp_from_thread_id (int tid /* thread_t? */) |
| { |
| td_thrhandle_t th; |
| td_err_e ret; |
| |
| if ((ret = p_td_ta_map_id2thr (main_threadagent, tid, &th)) != TD_OK) |
| error ("get_lwp_from_thread_id: map_id2thr failed: %s", |
| thr_err_string (ret)); |
| |
| return get_lwp_from_thread_handle (&th); |
| } |
| |
| /* |
| * pid_to_str has to handle user-space threads. |
| * If not a user-space thread, then pass the request on to the |
| * underlying stratum if it can handle it: else call normal_pid_to_str. |
| */ |
| |
| static char * |
| thread_db_pid_to_str (int pid) |
| { |
| static char buf[100]; |
| td_thrhandle_t th; |
| td_thrinfo_t ti; |
| td_err_e ret; |
| |
| if (is_thread (pid)) |
| { |
| if ((ret = p_td_ta_map_id2thr (main_threadagent, |
| GET_THREAD (pid), |
| &th)) != TD_OK) |
| error ("thread_db: map_id2thr failed: %s", thr_err_string (ret)); |
| |
| if ((ret = p_td_thr_get_info (&th, &ti)) != TD_OK) |
| error ("thread_db: thr_get_info failed: %s", thr_err_string (ret)); |
| |
| if (ti.ti_state == TD_THR_ACTIVE && |
| ti.ti_lid != 0) |
| sprintf (buf, "Thread %d (LWP %d)", ti.ti_tid, ti.ti_lid); |
| else |
| sprintf (buf, "Thread %d (%s)", ti.ti_tid, |
| thr_state_string (ti.ti_state)); |
| } |
| else if (GET_LWP (pid)) |
| sprintf (buf, "LWP %d", GET_LWP (pid)); |
| else return normal_pid_to_str (pid); |
| |
| return buf; |
| } |
| |
| /* |
| * thread_db target vector functions: |
| */ |
| |
| static void |
| thread_db_files_info (struct target_ops *tgt_vector) |
| { |
| /* This function will be unnecessary in real life. */ |
| printf_filtered ("thread_db stratum:\n"); |
| target_beneath->to_files_info (tgt_vector); |
| } |
| |
| /* |
| * xfer_memory has to munge the inferior_pid before passing the call |
| * down to the target layer. |
| */ |
| |
| static int |
| thread_db_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int dowrite, |
| struct target_ops *target) |
| { |
| struct cleanup *old_chain; |
| int ret; |
| |
| old_chain = save_inferior_pid (); |
| |
| if (is_thread (inferior_pid) || |
| !target_thread_alive (inferior_pid)) |
| { |
| /* FIXME: use the LID/LWP, so that underlying process layer |
| can read memory from specific threads? */ |
| inferior_pid = main_prochandle.pid; |
| } |
| |
| ret = target_beneath->to_xfer_memory (memaddr, myaddr, len, |
| dowrite, target); |
| do_cleanups (old_chain); |
| return ret; |
| } |
| |
| /* |
| * fetch_registers has to determine if inferior_pid is a user-space thread. |
| * If so, we use the thread_db API to get the registers. |
| * And if not, we call the underlying process stratum. |
| */ |
| |
| static void |
| thread_db_fetch_registers (int regno) |
| { |
| td_thrhandle_t thandle; |
| gdb_prfpregset_t fpregset; |
| prgregset_t gregset; |
| thread_t thread; |
| td_err_e ret; |
| |
| if (!is_thread (inferior_pid)) /* kernel thread */ |
| { /* pass the request on to the target underneath. */ |
| target_beneath->to_fetch_registers (regno); |
| return; |
| } |
| |
| /* convert inferior_pid into a td_thrhandle_t */ |
| |
| if ((thread = GET_THREAD (inferior_pid)) == 0) |
| error ("fetch_registers: thread == 0"); |
| |
| if ((ret = p_td_ta_map_id2thr (main_threadagent, thread, &thandle)) != TD_OK) |
| error ("fetch_registers: td_ta_map_id2thr: %s", thr_err_string (ret)); |
| |
| /* Get the integer regs: |
| For the sparc, TD_PARTIALREG means that only i0->i7, l0->l7, |
| pc and sp are saved (by a thread context switch). */ |
| if ((ret = p_td_thr_getgregs (&thandle, gregset)) != TD_OK && |
| ret != TD_PARTIALREG) |
| error ("fetch_registers: td_thr_getgregs %s", thr_err_string (ret)); |
| |
| /* And, now the fp regs */ |
| if ((ret = p_td_thr_getfpregs (&thandle, &fpregset)) != TD_OK && |
| ret != TD_NOFPREGS) |
| error ("fetch_registers: td_thr_getfpregs %s", thr_err_string (ret)); |
| |
| /* Note that we must call supply_{g fp}regset *after* calling the td routines |
| because the td routines call ps_lget* which affect the values stored in the |
| registers array. */ |
| |
| supply_gregset (gregset); |
| supply_fpregset (&fpregset); |
| |
| } |
| |
| /* |
| * store_registers has to determine if inferior_pid is a user-space thread. |
| * If so, we use the thread_db API to get the registers. |
| * And if not, we call the underlying process stratum. |
| */ |
| |
| static void |
| thread_db_store_registers (int regno) |
| { |
| td_thrhandle_t thandle; |
| gdb_prfpregset_t fpregset; |
| prgregset_t gregset; |
| thread_t thread; |
| td_err_e ret; |
| |
| if (!is_thread (inferior_pid)) /* Kernel thread: */ |
| { /* pass the request on to the underlying target vector. */ |
| target_beneath->to_store_registers (regno); |
| return; |
| } |
| |
| /* convert inferior_pid into a td_thrhandle_t */ |
| |
| if ((thread = GET_THREAD (inferior_pid)) == 0) |
| error ("store_registers: thread == 0"); |
| |
| if ((ret = p_td_ta_map_id2thr (main_threadagent, thread, &thandle)) != TD_OK) |
| error ("store_registers: td_ta_map_id2thr %s", thr_err_string (ret)); |
| |
| if (regno != -1) |
| { /* Not writing all the regs */ |
| /* save new register value */ |
| /* MVS: I don't understand this... */ |
| char old_value[REGISTER_SIZE]; |
| |
| memcpy (old_value, ®isters[REGISTER_BYTE (regno)], REGISTER_SIZE); |
| |
| if ((ret = p_td_thr_getgregs (&thandle, gregset)) != TD_OK) |
| error ("store_registers: td_thr_getgregs %s", thr_err_string (ret)); |
| if ((ret = p_td_thr_getfpregs (&thandle, &fpregset)) != TD_OK) |
| error ("store_registers: td_thr_getfpregs %s", thr_err_string (ret)); |
| |
| /* restore new register value */ |
| memcpy (®isters[REGISTER_BYTE (regno)], old_value, REGISTER_SIZE); |
| |
| } |
| |
| fill_gregset (gregset, regno); |
| fill_fpregset (&fpregset, regno); |
| |
| if ((ret = p_td_thr_setgregs (&thandle, gregset)) != TD_OK) |
| error ("store_registers: td_thr_setgregs %s", thr_err_string (ret)); |
| if ((ret = p_td_thr_setfpregs (&thandle, &fpregset)) != TD_OK && |
| ret != TD_NOFPREGS) |
| error ("store_registers: td_thr_setfpregs %s", thr_err_string (ret)); |
| } |
| |
| static void |
| handle_new_thread (int tid, /* user thread id */ |
| int lid, /* kernel thread id */ |
| int verbose) |
| { |
| int gdb_pid = BUILD_THREAD (tid, main_prochandle.pid); |
| int wait_pid, wait_status; |
| |
| if (verbose) |
| printf_filtered ("[New %s]\n", target_pid_to_str (gdb_pid)); |
| add_thread (gdb_pid); |
| |
| if (lid != main_prochandle.pid) |
| { |
| attach_thread (lid); |
| /* According to the Eric Paire model, we now have to send |
| the restart signal to the new thread -- however, empirically, |
| I do not find that to be necessary. */ |
| attach_pid = lid; |
| } |
| } |
| |
| static void |
| test_for_new_thread (int tid, int lid, int verbose) |
| { |
| if (!in_thread_list (BUILD_THREAD (tid, main_prochandle.pid))) |
| handle_new_thread (tid, lid, verbose); |
| } |
| |
| /* |
| * Callback function that gets called once per USER thread |
| * (i.e., not kernel) thread by td_ta_thr_iter. |
| */ |
| |
| static int |
| find_new_threads_callback (const td_thrhandle_t *th, void *ignored) |
| { |
| td_thrinfo_t ti; |
| td_err_e ret; |
| |
| if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| { |
| warning ("find_new_threads_callback: %s", thr_err_string (ret)); |
| return -1; /* bail out, get_info failed. */ |
| } |
| |
| /* FIXME: |
| As things now stand, this should never detect a new thread. |
| But if it does, we could be in trouble because we aren't calling |
| wait_thread_callback for it. */ |
| test_for_new_thread (ti.ti_tid, ti.ti_lid, 0); |
| return 0; |
| } |
| |
| /* |
| * find_new_threads uses the thread_db iterator function to discover |
| * user-space threads. Then if the underlying process stratum has a |
| * find_new_threads method, we call that too. |
| */ |
| |
| static void |
| thread_db_find_new_threads (void) |
| { |
| if (inferior_pid == -1) /* FIXME: still necessary? */ |
| { |
| printf_filtered ("No process.\n"); |
| return; |
| } |
| p_td_ta_thr_iter (main_threadagent, |
| find_new_threads_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_LOWEST_PRIORITY, |
| TD_SIGNO_MASK, |
| TD_THR_ANY_USER_FLAGS); |
| if (target_beneath->to_find_new_threads) |
| target_beneath->to_find_new_threads (); |
| } |
| |
| /* |
| * Resume all threads, or resume a single thread. |
| * If step is true, then single-step the appropriate thread |
| * (or single-step inferior_pid, but continue everyone else). |
| * If signo is true, then send that signal to at least one thread. |
| */ |
| |
| /* |
| * This function is called once for each thread before resuming. |
| * It sends continue (no step, and no signal) to each thread except |
| * the main thread, and |
| * the event thread (the one that stopped at a breakpoint etc.) |
| * |
| * The event thread is handled separately so that it can be sent |
| * the stepping and signal args with which target_resume was called. |
| * |
| * The main thread is resumed last, so that the thread_db proc_service |
| * callbacks will still work during the iterator function. |
| */ |
| |
| static int |
| resume_thread_callback (const td_thrhandle_t *th, void *data) |
| { |
| td_thrinfo_t ti; |
| td_err_e ret; |
| |
| if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| { |
| warning ("resume_thread_callback: %s", thr_err_string (ret)); |
| return -1; /* bail out, get_info failed. */ |
| } |
| /* FIXME: |
| As things now stand, this should never detect a new thread. |
| But if it does, we could be in trouble because we aren't calling |
| wait_thread_callback for it. */ |
| test_for_new_thread (ti.ti_tid, ti.ti_lid, 1); |
| |
| if (ti.ti_lid != main_prochandle.pid && |
| ti.ti_lid != event_pid) |
| { |
| /* Unconditionally continue the thread with no signal. |
| Only the event thread will get a signal of any kind. */ |
| |
| target_beneath->to_resume (ti.ti_lid, 0, 0); |
| } |
| return 0; |
| } |
| |
| static int |
| new_resume_thread_callback (threadinfo *thread, void *data) |
| { |
| if (thread->lid != event_pid && |
| thread->lid != main_prochandle.pid) |
| { |
| /* Unconditionally continue the thread with no signal (for now). */ |
| |
| target_beneath->to_resume (thread->lid, 0, 0); |
| } |
| return 0; |
| } |
| |
| static int last_resume_pid; |
| static int last_resume_step; |
| static int last_resume_signo; |
| |
| static void |
| thread_db_resume (int pid, int step, enum target_signal signo) |
| { |
| last_resume_pid = pid; |
| last_resume_step = step; |
| last_resume_signo = signo; |
| |
| /* resuming a specific pid? */ |
| if (pid != -1) |
| { |
| if (is_thread (pid)) |
| pid = get_lwp_from_thread_id (GET_THREAD (pid)); |
| else if (GET_LWP (pid)) |
| pid = GET_LWP (pid); |
| } |
| |
| /* Apparently the interpretation of 'pid' is dependent on 'step': |
| If step is true, then a specific pid means 'step only this pid'. |
| But if step is not true, then pid means 'continue ALL pids, but |
| give the signal only to this one'. */ |
| if (pid != -1 && step) |
| { |
| /* FIXME: is this gonna work in all circumstances? */ |
| target_beneath->to_resume (pid, step, signo); |
| } |
| else |
| { |
| /* 1) Continue all threads except the event thread and the main thread. |
| 2) resume the event thread with step and signo. |
| 3) If event thread != main thread, continue the main thread. |
| |
| Note: order of 2 and 3 may need to be reversed. */ |
| |
| threadlist_iter (new_resume_thread_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_ANY_TYPE); |
| /* now resume event thread, and if necessary also main thread. */ |
| if (event_pid) |
| { |
| target_beneath->to_resume (event_pid, step, signo); |
| } |
| if (event_pid != main_prochandle.pid) |
| { |
| target_beneath->to_resume (main_prochandle.pid, 0, 0); |
| } |
| } |
| } |
| |
| /* All new threads will be attached. |
| All previously known threads will be stopped using kill (SIGKILL). */ |
| |
| static int |
| stop_or_attach_thread_callback (const td_thrhandle_t *th, void *data) |
| { |
| td_thrinfo_t ti; |
| td_err_e ret; |
| int gdb_pid; |
| int on_off = 1; |
| |
| if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| { |
| warning ("stop_or_attach_thread_callback: %s", thr_err_string (ret)); |
| return -1; /* bail out, get_info failed. */ |
| } |
| |
| /* First add it to our internal list. |
| We build this list anew at every wait event. */ |
| insert_thread (ti.ti_tid, ti.ti_lid, ti.ti_state, ti.ti_type); |
| /* Now: if we've already seen it, stop it, else add it and attach it. */ |
| gdb_pid = BUILD_THREAD (ti.ti_tid, main_prochandle.pid); |
| if (!in_thread_list (gdb_pid)) /* new thread */ |
| { |
| handle_new_thread (ti.ti_tid, ti.ti_lid, 1); |
| /* Enable thread events */ |
| if (p_td_thr_event_enable) |
| if ((ret = p_td_thr_event_enable (th, on_off)) != TD_OK) |
| warning ("stop_or_attach_thread: %s", thr_err_string (ret)); |
| } |
| else if (ti.ti_lid != event_pid && |
| ti.ti_lid != main_prochandle.pid) |
| { |
| ret = (td_err_e) kill (ti.ti_lid, SIGSTOP); |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Wait for signal N from pid PID. |
| * If wait returns any other signals, put them back before returning. |
| */ |
| |
| static void |
| wait_for_stop (int pid) |
| { |
| int i; |
| int retpid; |
| int status; |
| |
| /* Array of wait/signal status */ |
| /* FIXME: wrong data structure, we need a queue. |
| Realtime signals may be delivered more than once. |
| And at that, we really can't handle them (see below). */ |
| #if defined (NSIG) |
| static int wstatus [NSIG]; |
| #elif defined (_NSIG) |
| static int wstatus [_NSIG]; |
| #else |
| #error No definition for number of signals! |
| #endif |
| |
| /* clear wait/status list */ |
| memset (&wstatus, 0, sizeof (wstatus)); |
| |
| /* Now look for SIGSTOP event on all threads except event thread. */ |
| do { |
| errno = 0; |
| if (pid == main_prochandle.pid) |
| retpid = waitpid (pid, &status, 0); |
| else |
| retpid = waitpid (pid, &status, __WCLONE); |
| |
| if (retpid > 0) |
| if (WSTOPSIG (status) == SIGSTOP) |
| { |
| /* Got the SIGSTOP event we're looking for. |
| Throw it away, and throw any other events back! */ |
| for (i = 0; i < sizeof(wstatus) / sizeof (wstatus[0]); i++) |
| if (wstatus[i]) |
| if (i != SIGSTOP) |
| { |
| kill (retpid, i); |
| } |
| break; /* all done */ |
| } |
| else |
| { |
| int signo; |
| /* Oops, got an event other than SIGSTOP. |
| Save it, and throw it back after we find the SIGSTOP event. */ |
| |
| /* FIXME (how?) This method is going to fail for realtime |
| signals, which cannot be put back simply by using kill. */ |
| |
| if (WIFEXITED (status)) |
| error ("Ack! Thread Exited event. What do I do now???"); |
| else if (WIFSTOPPED (status)) |
| signo = WSTOPSIG (status); |
| else |
| signo = WTERMSIG (status); |
| |
| /* If a thread other than the event thread has hit a GDB |
| breakpoint (as opposed to some random trap signal), then |
| just arrange for it to hit it again later. Back up the |
| PC if necessary. Don't forward the SIGTRAP signal to |
| the thread. We will handle the current event, eventually |
| we will resume all the threads, and this one will get |
| it's breakpoint trap again. |
| |
| If we do not do this, then we run the risk that the user |
| will delete or disable the breakpoint, but the thread will |
| have already tripped on it. */ |
| |
| if (retpid != event_pid && |
| signo == SIGTRAP && |
| breakpoint_inserted_here_p (read_pc_pid (retpid) - |
| DECR_PC_AFTER_BREAK)) |
| { |
| /* Set the pc to before the trap and DO NOT re-send the signal */ |
| if (DECR_PC_AFTER_BREAK) |
| write_pc_pid (read_pc_pid (retpid) - DECR_PC_AFTER_BREAK, |
| retpid); |
| } |
| |
| /* Since SIGINT gets forwarded to the entire process group |
| (in the case where ^C is typed at the tty / console), |
| just ignore all SIGINTs from other than the event thread. */ |
| else if (retpid != event_pid && signo == SIGINT) |
| { /* do nothing. Signal will disappear into oblivion! */ |
| ; |
| } |
| |
| else /* This is some random signal other than a breakpoint. */ |
| { |
| wstatus [signo] = 1; |
| } |
| child_resume (retpid, 0, TARGET_SIGNAL_0); |
| continue; |
| } |
| |
| } while (errno == 0 || errno == EINTR); |
| } |
| |
| /* |
| * wait_thread_callback |
| * |
| * Calls waitpid for each thread, repeatedly if necessary, until |
| * SIGSTOP is returned. Afterward, if any other signals were returned |
| * by waitpid, return them to the thread's pending queue by calling kill. |
| */ |
| |
| static int |
| wait_thread_callback (const td_thrhandle_t *th, void *data) |
| { |
| td_thrinfo_t ti; |
| td_err_e ret; |
| |
| if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| { |
| warning ("wait_thread_callback: %s", thr_err_string (ret)); |
| return -1; /* bail out, get_info failed. */ |
| } |
| |
| /* This callback to act on all threads except the event thread: */ |
| if (ti.ti_lid == event_pid || /* no need to wait (no sigstop) */ |
| ti.ti_lid == main_prochandle.pid) /* no need to wait (already waited) */ |
| return 0; /* don't wait on the event thread. */ |
| |
| wait_for_stop (ti.ti_lid); |
| return 0; /* finished: next thread. */ |
| } |
| |
| static int |
| new_wait_thread_callback (threadinfo *thread, void *data) |
| { |
| /* don't wait on the event thread -- it's already stopped and waited. |
| Ditto the main thread. */ |
| if (thread->lid != event_pid && |
| thread->lid != main_prochandle.pid) |
| { |
| wait_for_stop (thread->lid); |
| } |
| return 0; |
| } |
| |
| /* |
| * Wait for any thread to stop, by calling the underlying wait method. |
| * The PID returned by the underlying target may be a kernel thread, |
| * in which case we will want to convert it to the corresponding |
| * user-space thread. |
| */ |
| |
| static int |
| thread_db_wait (int pid, struct target_waitstatus *ourstatus) |
| { |
| td_thrhandle_t thandle; |
| td_thrinfo_t ti; |
| td_err_e ret; |
| lwpid_t lwp; |
| int retpid; |
| int status; |
| int save_errno; |
| |
| /* OK, we're about to wait for an event from the running inferior. |
| Make sure we're ignoring the right signals. */ |
| |
| check_all_signal_numbers (); /* see if magic signals changed. */ |
| |
| event_pid = 0; |
| attach_pid = 0; |
| |
| /* FIXME: should I do the wait right here inline? */ |
| #if 0 |
| if (pid == -1) |
| lwp = -1; |
| else |
| lwp = get_lwp_from_thread_id (GET_THREAD (pid)); |
| #endif |
| |
| |
| save_errno = linux_child_wait (-1, &retpid, &status); |
| store_waitstatus (ourstatus, status); |
| |
| /* Thread ID is irrelevant if the target process exited. |
| FIXME: do I have any killing to do? |
| Can I get this event mistakenly from a thread? */ |
| if (ourstatus->kind == TARGET_WAITKIND_EXITED) |
| return retpid; |
| |
| /* OK, we got an event of interest. |
| Go stop all threads and look for new ones. |
| FIXME: maybe don't do this for the restart signal? Optimization... */ |
| event_pid = retpid; |
| |
| /* If the last call to resume was for a specific thread, then we don't |
| need to stop everyone else: they should already be stopped. */ |
| if (last_resume_step == 0 || last_resume_pid == -1) |
| { |
| /* Main thread must be stopped before calling the iterator. */ |
| if (retpid != main_prochandle.pid) |
| { |
| kill (main_prochandle.pid, SIGSTOP); |
| wait_for_stop (main_prochandle.pid); |
| } |
| |
| empty_threadlist (); |
| /* Now stop everyone else, and attach any new threads you find. */ |
| p_td_ta_thr_iter (main_threadagent, |
| stop_or_attach_thread_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_LOWEST_PRIORITY, |
| TD_SIGNO_MASK, |
| TD_THR_ANY_USER_FLAGS); |
| |
| /* Now go call wait on all the threads we've stopped: |
| This allows us to absorb the SIGKILL event, and to make sure |
| that the thread knows that it is stopped (Linux peculiarity). */ |
| |
| threadlist_iter (new_wait_thread_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_ANY_TYPE); |
| } |
| |
| /* Convert the kernel thread id to the corresponding thread id. */ |
| |
| /* If the process layer does not furnish an lwp, |
| then perhaps the returned pid IS the lwp... */ |
| if ((lwp = GET_LWP (retpid)) == 0) |
| lwp = retpid; |
| |
| if ((ret = p_td_ta_map_lwp2thr (main_threadagent, lwp, &thandle)) != TD_OK) |
| return retpid; /* LWP is not mapped onto a user-space thread. */ |
| |
| if ((ret = p_td_thr_validate (&thandle)) != TD_OK) |
| return retpid; /* LWP is not mapped onto a valid thread. */ |
| |
| if ((ret = p_td_thr_get_info (&thandle, &ti)) != TD_OK) |
| { |
| warning ("thread_db: thr_get_info failed ('%s')", thr_err_string (ret)); |
| return retpid; |
| } |
| |
| retpid = BUILD_THREAD (ti.ti_tid, main_prochandle.pid); |
| /* If this is a new user thread, notify GDB about it. */ |
| if (!in_thread_list (retpid)) |
| { |
| printf_filtered ("[New %s]\n", target_pid_to_str (retpid)); |
| add_thread (retpid); |
| } |
| |
| #if 0 |
| /* Now detect if this is a thread creation/deletion event: */ |
| check_for_thread_event (ourstatus, retpid); |
| #endif |
| return retpid; |
| } |
| |
| /* |
| * kill has to call the underlying kill. |
| * FIXME: I'm not sure if it's necessary to check inferior_pid any more, |
| * but we might need to fix inferior_pid up if it's a user thread. |
| */ |
| |
| static int |
| kill_thread_callback (td_thrhandle_t *th, void *data) |
| { |
| td_thrinfo_t ti; |
| td_err_e ret; |
| |
| /* Fixme: |
| For Linux, threads may need to be waited. */ |
| if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| { |
| warning ("kill_thread_callback: %s", thr_err_string (ret)); |
| return -1; /* bail out, get_info failed. */ |
| } |
| |
| if (ti.ti_lid != main_prochandle.pid) |
| { |
| kill (ti.ti_lid, SIGKILL); |
| } |
| return 0; |
| } |
| |
| |
| static void thread_db_kill (void) |
| { |
| int rpid; |
| int status; |
| |
| /* Fixme: |
| For Linux, threads may need to be waited. */ |
| if (inferior_pid != 0) |
| { |
| /* Go kill the children first. Save the main thread for last. */ |
| p_td_ta_thr_iter (main_threadagent, |
| kill_thread_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_LOWEST_PRIORITY, |
| TD_SIGNO_MASK, |
| TD_THR_ANY_USER_FLAGS); |
| |
| /* Turn off thread_db event-reporting API *before* killing the |
| main thread, since this operation requires child memory access. |
| Can't move this into thread_db_unpush target because then |
| detach would not work. */ |
| disable_thread_event_reporting (main_threadagent); |
| |
| inferior_pid = main_prochandle.pid; |
| |
| /* |
| * Since both procfs_kill and ptrace_kill call target_mourn, |
| * it should be sufficient for me to call one of them. |
| * That will result in my mourn being called, which will both |
| * unpush me and call the underlying mourn. |
| */ |
| target_beneath->to_kill (); |
| } |
| |
| /* Wait for all threads. */ |
| /* FIXME: need a universal wait_for_signal func? */ |
| do |
| { |
| rpid = waitpid (-1, &status, __WCLONE | WNOHANG); |
| } |
| while (rpid > 0 || errno == EINTR); |
| |
| do |
| { |
| rpid = waitpid (-1, &status, WNOHANG); |
| } |
| while (rpid > 0 || errno == EINTR); |
| } |
| |
| /* |
| * Mourn has to remove us from the target stack, |
| * and then call the underlying mourn. |
| */ |
| |
| static void thread_db_mourn_inferior (void) |
| { |
| thread_db_unpush_target (); |
| target_mourn_inferior (); /* call the underlying mourn */ |
| } |
| |
| /* |
| * Detach has to remove us from the target stack, |
| * and then call the underlying detach. |
| * |
| * But first, it has to detach all the cloned threads! |
| */ |
| |
| static int |
| detach_thread_callback (td_thrhandle_t *th, void *data) |
| { |
| /* Called once per thread. */ |
| td_thrinfo_t ti; |
| td_err_e ret; |
| |
| if ((ret = p_td_thr_get_info (th, &ti)) != TD_OK) |
| { |
| warning ("detach_thread_callback: %s", thr_err_string (ret)); |
| return -1; /* bail out, get_info failed. */ |
| } |
| |
| if (!in_thread_list (BUILD_THREAD (ti.ti_tid, main_prochandle.pid))) |
| return 0; /* apparently we don't know this one. */ |
| |
| /* Save main thread for last, or the iterator will fail! */ |
| if (ti.ti_lid != main_prochandle.pid) |
| { |
| struct cleanup *old_chain; |
| int off = 0; |
| |
| /* Time to detach this thread. |
| First disable thread_db event reporting for the thread. */ |
| if (p_td_thr_event_enable && |
| (ret = p_td_thr_event_enable (th, off)) != TD_OK) |
| { |
| warning ("detach_thread_callback: %s\n", thr_err_string (ret)); |
| return 0; |
| } |
| |
| /* Now cancel any pending SIGTRAPS. FIXME! */ |
| |
| /* Call underlying detach method. FIXME just detach it. */ |
| old_chain = save_inferior_pid (); |
| inferior_pid = ti.ti_lid; |
| detach (TARGET_SIGNAL_0); |
| do_cleanups (old_chain); |
| } |
| return 0; |
| } |
| |
| static void |
| thread_db_detach (char *args, int from_tty) |
| { |
| td_err_e ret; |
| |
| if ((ret = p_td_ta_thr_iter (main_threadagent, |
| detach_thread_callback, |
| (void *) 0, |
| TD_THR_ANY_STATE, |
| TD_THR_LOWEST_PRIORITY, |
| TD_SIGNO_MASK, |
| TD_THR_ANY_USER_FLAGS)) |
| != TD_OK) |
| warning ("detach (thr_iter): %s", thr_err_string (ret)); |
| |
| /* Turn off thread_db event-reporting API |
| (before detaching the main thread) */ |
| disable_thread_event_reporting (main_threadagent); |
| |
| thread_db_unpush_target (); |
| |
| /* above call nullifies target_beneath, so don't use that! */ |
| inferior_pid = PIDGET (inferior_pid); |
| target_detach (args, from_tty); |
| } |
| |
| |
| /* |
| * We never want to actually create the inferior! |
| * |
| * If this is ever called, it means we were on the target stack |
| * when the user said "run". But we don't want to be on the new |
| * inferior's target stack until the thread_db / libthread |
| * connection is ready to be made. |
| * |
| * So, what shall we do? |
| * Unpush ourselves from the stack, and then invoke |
| * find_default_create_inferior, which will invoke the |
| * appropriate process_stratum target to do the create. |
| */ |
| |
| static void |
| thread_db_create_inferior (char *exec_file, char *allargs, char **env) |
| { |
| thread_db_unpush_target (); |
| find_default_create_inferior (exec_file, allargs, env); |
| } |
| |
| /* |
| * Thread_db target vector initializer. |
| */ |
| |
| void |
| init_thread_db_ops (void) |
| { |
| thread_db_ops.to_shortname = "multi-thread"; |
| thread_db_ops.to_longname = "multi-threaded child process."; |
| thread_db_ops.to_doc = "Threads and pthreads support."; |
| thread_db_ops.to_files_info = thread_db_files_info; |
| thread_db_ops.to_create_inferior = thread_db_create_inferior; |
| thread_db_ops.to_detach = thread_db_detach; |
| thread_db_ops.to_wait = thread_db_wait; |
| thread_db_ops.to_resume = thread_db_resume; |
| thread_db_ops.to_mourn_inferior = thread_db_mourn_inferior; |
| thread_db_ops.to_kill = thread_db_kill; |
| thread_db_ops.to_xfer_memory = thread_db_xfer_memory; |
| thread_db_ops.to_fetch_registers = thread_db_fetch_registers; |
| thread_db_ops.to_store_registers = thread_db_store_registers; |
| thread_db_ops.to_thread_alive = thread_db_alive; |
| thread_db_ops.to_find_new_threads = thread_db_find_new_threads; |
| thread_db_ops.to_pid_to_str = thread_db_pid_to_str; |
| thread_db_ops.to_stratum = thread_stratum; |
| thread_db_ops.to_has_thread_control = tc_schedlock; |
| thread_db_ops.to_magic = OPS_MAGIC; |
| } |
| #endif /* HAVE_STDINT_H */ |
| |
| /* |
| * Module constructor / initializer function. |
| * If connection to thread_db dynamic library is successful, |
| * then initialize this module's target vectors and the |
| * new_objfile hook. |
| */ |
| |
| |
| void |
| _initialize_thread_db (void) |
| { |
| #ifdef HAVE_STDINT_H /* stub out entire module, leave initializer empty */ |
| if (init_thread_db_library ()) |
| { |
| init_thread_db_ops (); |
| add_target (&thread_db_ops); |
| /* |
| * Hook up to the new_objfile event. |
| * If someone is already there, arrange for him to be called |
| * after we are. |
| */ |
| target_new_objfile_chain = target_new_objfile_hook; |
| target_new_objfile_hook = thread_db_new_objfile; |
| } |
| #endif /* HAVE_STDINT_H */ |
| } |
| |