src/jdk.hotspot.agent/linux/native/libsaproc/ps_proc.c

*** 1,7 ****
  /*
!  * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
--- 1,7 ----
  /*
!  * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.
*** 20,41 ****
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   *
   */
  
- #ifdef INCLUDE_SA_ATTACH
- 
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <signal.h>
  #include <errno.h>
  #include <elf.h>
  #include <sys/types.h>
  #include <sys/wait.h>
  #include <sys/ptrace.h>
  #include <sys/uio.h>
  #include "libproc_impl.h"
  
  #if defined(x86_64) && !defined(amd64)
  #define amd64 1
  #endif
--- 20,42 ----
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   *
   */
  
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <signal.h>
  #include <errno.h>
  #include <elf.h>
  #include <sys/types.h>
  #include <sys/wait.h>
  #include <sys/ptrace.h>
  #include <sys/uio.h>
+ #ifndef INCLUDE_SA_ATTACH
+ #include <dirent.h>
+ #endif
  #include "libproc_impl.h"
  
  #if defined(x86_64) && !defined(amd64)
  #define amd64 1
  #endif
*** 218,230 ****
  
  // attach to a process/thread specified by "pid"
  static bool ptrace_attach(pid_t pid, char* err_buf, size_t err_buf_len) {
    if (ptrace(PTRACE_ATTACH, pid, NULL, NULL) < 0) {
      char buf[200];
!     char* msg = strerror_r(errno, buf, sizeof(buf));
!     snprintf(err_buf, err_buf_len, "ptrace(PTRACE_ATTACH, ..) failed for %d: %s", pid, msg);
      print_debug("%s\n", err_buf);
      return false;
    } else {
      return ptrace_waitpid(pid);
    }
  }
--- 219,233 ----
  
  // attach to a process/thread specified by "pid"
  static bool ptrace_attach(pid_t pid, char* err_buf, size_t err_buf_len) {
    if (ptrace(PTRACE_ATTACH, pid, NULL, NULL) < 0) {
      char buf[200];
!     if (strerror_r(errno, buf, sizeof(buf) == 0)) {
!       snprintf(err_buf, err_buf_len,
!                "ptrace(PTRACE_ATTACH, ..) failed for %d: %s", pid, buf);
        print_debug("%s\n", err_buf);
+     }
      return false;
    } else {
      return ptrace_waitpid(pid);
    }
  }
*** 399,421 ****
    // read library info and symbol tables, must do this before attaching threads,
    // as the symbols in the pthread library will be used to figure out
    // the list of threads within the same process.
    read_lib_info(ph);
  
    // read thread info
    read_thread_info(ph, add_new_thread);
  
    // attach to the threads
    thr = ph->threads;
    while (thr) {
       // don't attach to the main thread again
!     if (ph->pid != thr->lwp_id && ptrace_attach(thr->lwp_id, err_buf, err_buf_len) != true) {
          // even if one attach fails, we get return NULL
          Prelease(ph);
          return NULL;
       }
       thr = thr->next;
    }
    return ph;
  }
- 
- #endif // INCLUDE_SA_ATTACH
--- 402,458 ----
    // read library info and symbol tables, must do this before attaching threads,
    // as the symbols in the pthread library will be used to figure out
    // the list of threads within the same process.
    read_lib_info(ph);
  
+ #ifdef INCLUDE_SA_ATTACH
    // read thread info
    read_thread_info(ph, add_new_thread);
  
    // attach to the threads
    thr = ph->threads;
    while (thr) {
       // don't attach to the main thread again
!     if (pid != thr->lwp_id && ptrace_attach(thr->lwp_id, err_buf, err_buf_len) != true) {
          // even if one attach fails, we get return NULL
          Prelease(ph);
          return NULL;
       }
       thr = thr->next;
    }
+ #else
+   DIR *dir = NULL;
+   struct dirent *ent = NULL;
+   char taskpath[80];
+ 
+   // Find the lwpids to attach to by traversing the /proc/<pid>/task/ directory,
+   // and attach to those.
+   snprintf (taskpath, sizeof (taskpath), "/proc/%ld/task", (unsigned long) pid);
+   if ((dir = opendir(taskpath)) != NULL) {
+     while ((ent = readdir (dir)) != NULL) {
+       unsigned long lwp;
+ 
+       if ((lwp = strtoul (ent->d_name, NULL, 10)) != 0) {
+         add_new_thread (ph, 0, lwp);
+ 
+         // Don't attach to the main thread again
+         if (lwp == (unsigned long) pid) {
+           continue;
+         }
+ 
+         if (ptrace_attach(lwp, err_buf, err_buf_len) != true) {
+           Prelease(ph);
+           closedir (dir);
+           return NULL;
+         }
+       }
+     }
+   } else {
+     print_debug("Could not open /proc/%ld/task.\n", (unsigned long) pid);
+     Prelease(ph);
+     return NULL;
+   }
+ 
+   closedir (dir);
+ #endif
    return ph;
  }