diff options
Diffstat (limited to 'gdb/linux-nat.c')
| -rw-r--r-- | gdb/linux-nat.c | 46 |
1 files changed, 23 insertions, 23 deletions
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c index ec0433f..c769010 100644 --- a/gdb/linux-nat.c +++ b/gdb/linux-nat.c @@ -38,12 +38,12 @@ #include "inf-ptrace.h" #include "auxv.h" #include <sys/param.h> /* for MAXPATHLEN */ -#include <sys/procfs.h> /* for elf_gregset etc. */ +#include <sys/procfs.h> /* for elf_gregset etc. */ #include "elf-bfd.h" /* for elfcore_write_* */ #include "gregset.h" /* for gregset */ #include "gdbcore.h" /* for get_exec_file */ #include <ctype.h> /* for isdigit */ -#include "gdbthread.h" /* for struct thread_info etc. */ +#include "gdbthread.h" /* for struct thread_info etc. */ #include "gdb_stat.h" /* for struct stat */ #include <fcntl.h> /* for O_RDONLY */ #include "inf-loop.h" @@ -68,7 +68,7 @@ # endif #endif /* HAVE_PERSONALITY */ -/* This comment documents high-level logic of this file. +/* This comment documents high-level logic of this file. Waiting for events in sync mode =============================== @@ -76,12 +76,12 @@ Waiting for events in sync mode When waiting for an event in a specific thread, we just use waitpid, passing the specific pid, and not passing WNOHANG. -When waiting for an event in all threads, waitpid is not quite good. Prior to +When waiting for an event in all threads, waitpid is not quite good. Prior to version 2.4, Linux can either wait for event in main thread, or in secondary -threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might +threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might miss an event. The solution is to use non-blocking waitpid, together with sigsuspend. First, we use non-blocking waitpid to get an event in the main -process, if any. Second, we use non-blocking waitpid with the __WCLONED +process, if any. Second, we use non-blocking waitpid with the __WCLONED flag to check for events in cloned processes. If nothing is found, we use sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something happened to a child process -- and SIGCHLD will be delivered both for events @@ -90,7 +90,7 @@ an event, we get back to calling nonblocking waitpid with and without __WCLONED. Note that SIGCHLD should be blocked between waitpid and sigsuspend calls, -so that we don't miss a signal. If SIGCHLD arrives in between, when it's +so that we don't miss a signal. If SIGCHLD arrives in between, when it's blocked, the signal becomes pending and sigsuspend immediately notices it and returns. @@ -167,7 +167,7 @@ blocked. */ #define PTRACE_SETOPTIONS 0x4200 #define PTRACE_GETEVENTMSG 0x4201 -/* options set using PTRACE_SETOPTIONS */ +/* Options set using PTRACE_SETOPTIONS. */ #define PTRACE_O_TRACESYSGOOD 0x00000001 #define PTRACE_O_TRACEFORK 0x00000002 #define PTRACE_O_TRACEVFORK 0x00000004 @@ -297,7 +297,7 @@ static int linux_supports_tracesysgood_flag = -1; static int linux_supports_tracevforkdone_flag = -1; -/* Async mode support */ +/* Async mode support. */ /* Zero if the async mode, although enabled, is masked, which means linux_nat_wait should behave as if async mode was off. */ @@ -698,7 +698,7 @@ holding the child stopped. Try \"set detach-on-fork\" or \ { struct lwp_info *child_lp = NULL; - /* We're already attached to the parent, by default. */ + /* We're already attached to the parent, by default. */ /* Detach new forked process? */ if (detach_fork) @@ -2726,7 +2726,7 @@ stop_wait_callback (struct lwp_info *lp, void *data) save_sigtrap (lp); - /* Now resume this LWP and get the SIGSTOP event. */ + /* Now resume this LWP and get the SIGSTOP event. */ errno = 0; ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); if (debug_linux_nat) @@ -2741,12 +2741,12 @@ stop_wait_callback (struct lwp_info *lp, void *data) target_pid_to_str (lp->ptid)); } /* Hold this event/waitstatus while we check to see if - there are any more (we still want to get that SIGSTOP). */ + there are any more (we still want to get that SIGSTOP). */ stop_wait_callback (lp, NULL); /* Hold the SIGTRAP for handling by linux_nat_wait. If there's another event, throw it back into the - queue. */ + queue. */ if (lp->status) { if (debug_linux_nat) @@ -2757,14 +2757,14 @@ stop_wait_callback (struct lwp_info *lp, void *data) kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status)); } - /* Save the sigtrap event. */ + /* Save the sigtrap event. */ lp->status = status; return 0; } else { /* The thread was stopped with a signal other than - SIGSTOP, and didn't accidentally trip a breakpoint. */ + SIGSTOP, and didn't accidentally trip a breakpoint. */ if (debug_linux_nat) { @@ -2773,7 +2773,7 @@ stop_wait_callback (struct lwp_info *lp, void *data) status_to_str ((int) status), target_pid_to_str (lp->ptid)); } - /* Now resume this LWP and get the SIGSTOP event. */ + /* Now resume this LWP and get the SIGSTOP event. */ errno = 0; ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0); if (debug_linux_nat) @@ -2783,7 +2783,7 @@ stop_wait_callback (struct lwp_info *lp, void *data) errno ? safe_strerror (errno) : "OK"); /* Hold this event/waitstatus while we check to see if - there are any more (we still want to get that SIGSTOP). */ + there are any more (we still want to get that SIGSTOP). */ stop_wait_callback (lp, NULL); /* If the lp->status field is still empty, use it to @@ -2887,7 +2887,7 @@ select_event_lwp_callback (struct lwp_info *lp, void *data) gdb_assert (selector != NULL); - /* Select only resumed LWPs that have a SIGTRAP event pending. */ + /* Select only resumed LWPs that have a SIGTRAP event pending. */ if (lp->resumed && linux_nat_lp_status_is_event (lp)) if ((*selector)-- == 0) return 1; @@ -3065,7 +3065,7 @@ linux_nat_filter_event (int lwpid, int status, int options) } /* Make sure we don't report an event for the exit of an LWP not in - our list, i.e. not part of the current process. This can happen + our list, i.e. not part of the current process. This can happen if we detach from a program we original forked and then it exits. */ if (!WIFSTOPPED (status) && !lp) @@ -4569,7 +4569,7 @@ linux_nat_info_proc_cmd (char *args, int from_tty) } else { - /* [...] (future options here) */ + /* [...] (future options here). */ } argv++; } @@ -4769,9 +4769,9 @@ linux_nat_info_proc_cmd (char *args, int from_tty) printf_filtered (_("Start of stack: 0x%lx\n"), ltmp); #if 0 /* Don't know how architecture-dependent the rest is... Anyway the signal bitmap info is available from "status". */ - if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ + if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp); - if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ + if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp); if (fscanf (procfile, "%ld ", <mp) > 0) printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp); @@ -4781,7 +4781,7 @@ linux_nat_info_proc_cmd (char *args, int from_tty) printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp); if (fscanf (procfile, "%ld ", <mp) > 0) printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp); - if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ + if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */ printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp); #endif do_cleanups (cleanup); |