src/jdk.hotspot.agent/macosx/native/libsaproc/libproc_impl.c
changeset 47216 71c04702a3d5
parent 35516 f0d335e847c5
child 56109 5bf57be44328
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.hotspot.agent/macosx/native/libsaproc/libproc_impl.c	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,566 @@
+/*
+ * 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.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+#include "libproc_impl.h"
+
+static const char* alt_root = NULL;
+static int alt_root_len = -1;
+
+#define SA_ALTROOT "SA_ALTROOT"
+
+off_t ltell(int fd) {
+  return lseek(fd, 0, SEEK_CUR);
+}
+
+static void init_alt_root() {
+  if (alt_root_len == -1) {
+    alt_root = getenv(SA_ALTROOT);
+    if (alt_root) {
+      alt_root_len = strlen(alt_root);
+    } else {
+      alt_root_len = 0;
+    }
+  }
+}
+
+int pathmap_open(const char* name) {
+  int fd;
+  char alt_path[PATH_MAX + 1];
+
+  init_alt_root();
+
+  if (alt_root_len > 0) {
+    strcpy(alt_path, alt_root);
+    strcat(alt_path, name);
+    fd = open(alt_path, O_RDONLY);
+    if (fd >= 0) {
+      print_debug("path %s substituted for %s\n", alt_path, name);
+      return fd;
+    }
+
+    if (strrchr(name, '/')) {
+      strcpy(alt_path, alt_root);
+      strcat(alt_path, strrchr(name, '/'));
+      fd = open(alt_path, O_RDONLY);
+      if (fd >= 0) {
+        print_debug("path %s substituted for %s\n", alt_path, name);
+        return fd;
+      }
+    }
+  } else {
+    fd = open(name, O_RDONLY);
+    if (fd >= 0) {
+      return fd;
+    }
+  }
+  return -1;
+}
+
+static bool _libsaproc_debug;
+
+void print_debug(const char* format,...) {
+  if (_libsaproc_debug) {
+    va_list alist;
+
+    va_start(alist, format);
+    fputs("libsaproc DEBUG: ", stderr);
+    vfprintf(stderr, format, alist);
+    va_end(alist);
+  }
+}
+
+void print_error(const char* format,...) {
+  va_list alist;
+  va_start(alist, format);
+  fputs("ERROR: ", stderr);
+  vfprintf(stderr, format, alist);
+  va_end(alist);
+}
+
+bool is_debug() {
+  return _libsaproc_debug;
+}
+
+#ifdef __APPLE__
+// get arch offset in file
+bool get_arch_off(int fd, cpu_type_t cputype, off_t *offset) {
+  struct fat_header fatheader;
+  struct fat_arch fatarch;
+  off_t img_start = 0;
+
+  off_t pos = ltell(fd);
+  if (read(fd, (void *)&fatheader, sizeof(struct fat_header)) != sizeof(struct fat_header)) {
+    return false;
+  }
+  if (fatheader.magic == FAT_CIGAM) {
+    int i;
+    for (i = 0; i < ntohl(fatheader.nfat_arch); i++) {
+      if (read(fd, (void *)&fatarch, sizeof(struct fat_arch)) != sizeof(struct fat_arch)) {
+        return false;
+      }
+      if (ntohl(fatarch.cputype) == cputype) {
+        print_debug("fat offset=%x\n", ntohl(fatarch.offset));
+        img_start = ntohl(fatarch.offset);
+        break;
+      }
+    }
+    if (img_start == 0) {
+      return false;
+    }
+  }
+  lseek(fd, pos, SEEK_SET);
+  *offset = img_start;
+  return true;
+}
+
+bool is_macho_file(int fd) {
+  mach_header_64 fhdr;
+  off_t x86_64_off;
+
+  if (fd < 0) {
+    print_debug("Invalid file handle passed to is_macho_file\n");
+    return false;
+  }
+
+  off_t pos = ltell(fd);
+  // check fat header
+  if (!get_arch_off(fd, CPU_TYPE_X86_64, &x86_64_off)) {
+    print_debug("failed to get fat header\n");
+    return false;
+  }
+  lseek(fd, x86_64_off, SEEK_SET);
+  if (read(fd, (void *)&fhdr, sizeof(mach_header_64)) != sizeof(mach_header_64)) {
+     return false;
+  }
+  lseek(fd, pos, SEEK_SET);               // restore
+  print_debug("fhdr.magic %x\n", fhdr.magic);
+  return (fhdr.magic == MH_MAGIC_64 || fhdr.magic == MH_CIGAM_64);
+}
+
+#endif //__APPLE__
+
+// initialize libproc
+bool init_libproc(bool debug) {
+   _libsaproc_debug = debug;
+#ifndef __APPLE__
+   // initialize the thread_db library
+   if (td_init() != TD_OK) {
+     print_debug("libthread_db's td_init failed\n");
+     return false;
+   }
+#endif // __APPLE__
+   return true;
+}
+
+void destroy_lib_info(struct ps_prochandle* ph) {
+  lib_info* lib = ph->libs;
+  while (lib) {
+    lib_info* next = lib->next;
+    if (lib->symtab) {
+      destroy_symtab(lib->symtab);
+    }
+    free(lib);
+    lib = next;
+  }
+}
+
+void destroy_thread_info(struct ps_prochandle* ph) {
+  sa_thread_info* thr = ph->threads;
+  while (thr) {
+    sa_thread_info* n = thr->next;
+    free(thr);
+    thr = n;
+  }
+}
+
+// ps_prochandle cleanup
+void Prelease(struct ps_prochandle* ph) {
+  // do the "derived class" clean-up first
+  ph->ops->release(ph);
+  destroy_lib_info(ph);
+  destroy_thread_info(ph);
+  free(ph);
+}
+
+lib_info* add_lib_info(struct ps_prochandle* ph, const char* libname, uintptr_t base) {
+  return add_lib_info_fd(ph, libname, -1, base);
+}
+
+lib_info* add_lib_info_fd(struct ps_prochandle* ph, const char* libname, int fd, uintptr_t base) {
+   lib_info* newlib;
+  print_debug("add_lib_info_fd %s\n", libname);
+
+  if ( (newlib = (lib_info*) calloc(1, sizeof(struct lib_info))) == NULL) {
+    print_debug("can't allocate memory for lib_info\n");
+    return NULL;
+  }
+
+  if (strlen(libname) >= sizeof(newlib->name)) {
+    print_debug("libname %s too long\n", libname);
+    free(newlib);
+    return NULL;
+  }
+  strcpy(newlib->name, libname);
+
+  newlib->base = base;
+
+  if (fd == -1) {
+    if ( (newlib->fd = pathmap_open(newlib->name)) < 0) {
+      print_debug("can't open shared object %s\n", newlib->name);
+      free(newlib);
+      return NULL;
+    }
+  } else {
+    newlib->fd = fd;
+  }
+
+#ifdef __APPLE__
+  // check whether we have got an Macho file.
+  if (is_macho_file(newlib->fd) == false) {
+    close(newlib->fd);
+    free(newlib);
+    print_debug("not a mach-o file\n");
+    return NULL;
+  }
+#else
+  // check whether we have got an ELF file. /proc/<pid>/map
+  // gives out all file mappings and not just shared objects
+  if (is_elf_file(newlib->fd) == false) {
+    close(newlib->fd);
+    free(newlib);
+    return NULL;
+  }
+#endif // __APPLE__
+
+  newlib->symtab = build_symtab(newlib->fd);
+  if (newlib->symtab == NULL) {
+    print_debug("symbol table build failed for %s\n", newlib->name);
+  } else {
+    print_debug("built symbol table for %s\n", newlib->name);
+  }
+
+  // even if symbol table building fails, we add the lib_info.
+  // This is because we may need to read from the ELF file or MachO file for core file
+  // address read functionality. lookup_symbol checks for NULL symtab.
+  if (ph->libs) {
+    ph->lib_tail->next = newlib;
+    ph->lib_tail = newlib;
+  }  else {
+    ph->libs = ph->lib_tail = newlib;
+  }
+  ph->num_libs++;
+  return newlib;
+}
+
+// lookup for a specific symbol
+uintptr_t lookup_symbol(struct ps_prochandle* ph,  const char* object_name,
+                       const char* sym_name) {
+  // ignore object_name. search in all libraries
+  // FIXME: what should we do with object_name?? The library names are obtained
+  // by parsing /proc/<pid>/maps, which may not be the same as object_name.
+  // What we need is a utility to map object_name to real file name, something
+  // dlopen() does by looking at LD_LIBRARY_PATH and /etc/ld.so.cache. For
+  // now, we just ignore object_name and do a global search for the symbol.
+
+  lib_info* lib = ph->libs;
+  while (lib) {
+    if (lib->symtab) {
+      uintptr_t res = search_symbol(lib->symtab, lib->base, sym_name, NULL);
+      if (res) return res;
+    }
+    lib = lib->next;
+  }
+
+  print_debug("lookup failed for symbol '%s' in obj '%s'\n",
+                          sym_name, object_name);
+  return (uintptr_t) NULL;
+}
+
+const char* symbol_for_pc(struct ps_prochandle* ph, uintptr_t addr, uintptr_t* poffset) {
+  const char* res = NULL;
+  lib_info* lib = ph->libs;
+  while (lib) {
+    if (lib->symtab && addr >= lib->base) {
+      res = nearest_symbol(lib->symtab, addr - lib->base, poffset);
+      if (res) return res;
+    }
+    lib = lib->next;
+  }
+  return NULL;
+}
+
+// add a thread to ps_prochandle
+sa_thread_info* add_thread_info(struct ps_prochandle* ph, pthread_t pthread_id, lwpid_t lwp_id) {
+  sa_thread_info* newthr;
+  if ( (newthr = (sa_thread_info*) calloc(1, sizeof(sa_thread_info))) == NULL) {
+    print_debug("can't allocate memory for thread_info\n");
+    return NULL;
+  }
+
+  // initialize thread info
+  newthr->pthread_id = pthread_id;
+  newthr->lwp_id = lwp_id;
+
+  // add new thread to the list
+  newthr->next = ph->threads;
+  ph->threads = newthr;
+  ph->num_threads++;
+  return newthr;
+}
+
+#ifndef __APPLE__
+// struct used for client data from thread_db callback
+struct thread_db_client_data {
+  struct ps_prochandle* ph;
+  thread_info_callback callback;
+};
+
+// callback function for libthread_db
+static int thread_db_callback(const td_thrhandle_t *th_p, void *data) {
+  struct thread_db_client_data* ptr = (struct thread_db_client_data*) data;
+  td_thrinfo_t ti;
+  td_err_e err;
+
+  memset(&ti, 0, sizeof(ti));
+  err = td_thr_get_info(th_p, &ti);
+  if (err != TD_OK) {
+    print_debug("libthread_db : td_thr_get_info failed, can't get thread info\n");
+    return err;
+  }
+
+  print_debug("thread_db : pthread %d (lwp %d)\n", ti.ti_tid, ti.ti_lid);
+
+  if (ptr->callback(ptr->ph, (pthread_t)ti.ti_tid, ti.ti_lid) != true)
+    return TD_ERR;
+
+  return TD_OK;
+}
+
+// read thread_info using libthread_db
+bool read_thread_info(struct ps_prochandle* ph, thread_info_callback cb) {
+  struct thread_db_client_data mydata;
+  td_thragent_t* thread_agent = NULL;
+  if (td_ta_new(ph, &thread_agent) != TD_OK) {
+     print_debug("can't create libthread_db agent\n");
+     return false;
+  }
+
+  mydata.ph = ph;
+  mydata.callback = cb;
+
+  // we use libthread_db iterator to iterate thru list of threads.
+  if (td_ta_thr_iter(thread_agent, thread_db_callback, &mydata,
+                 TD_THR_ANY_STATE, TD_THR_LOWEST_PRIORITY,
+                 TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS) != TD_OK) {
+     td_ta_delete(thread_agent);
+     return false;
+  }
+
+  // delete thread agent
+  td_ta_delete(thread_agent);
+  return true;
+}
+
+#endif // __APPLE__
+
+// get number of threads
+int get_num_threads(struct ps_prochandle* ph) {
+   return ph->num_threads;
+}
+
+// get lwp_id of n'th thread
+lwpid_t get_lwp_id(struct ps_prochandle* ph, int index) {
+  int count = 0;
+  sa_thread_info* thr = ph->threads;
+  while (thr) {
+    if (count == index) {
+      return thr->lwp_id;
+    }
+    count++;
+    thr = thr->next;
+  }
+  return 0;
+}
+
+#ifdef __APPLE__
+// set lwp_id of n'th thread
+bool set_lwp_id(struct ps_prochandle* ph, int index, lwpid_t lwpid) {
+  int count = 0;
+  sa_thread_info* thr = ph->threads;
+  while (thr) {
+    if (count == index) {
+      thr->lwp_id = lwpid;
+      return true;
+    }
+    count++;
+    thr = thr->next;
+  }
+  return false;
+}
+
+// get regs of n-th thread, only used in fillThreads the first time called
+bool get_nth_lwp_regs(struct ps_prochandle* ph, int index, struct reg* regs) {
+  int count = 0;
+  sa_thread_info* thr = ph->threads;
+  while (thr) {
+    if (count == index) {
+      break;
+    }
+    count++;
+    thr = thr->next;
+  }
+  if (thr != NULL) {
+    memcpy(regs, &thr->regs, sizeof(struct reg));
+    return true;
+  }
+  return false;
+}
+
+#endif // __APPLE__
+
+// get regs for a given lwp
+bool get_lwp_regs(struct ps_prochandle* ph, lwpid_t lwp_id, struct reg* regs) {
+  return ph->ops->get_lwp_regs(ph, lwp_id, regs);
+}
+
+// get number of shared objects
+int get_num_libs(struct ps_prochandle* ph) {
+  return ph->num_libs;
+}
+
+// get name of n'th solib
+const char* get_lib_name(struct ps_prochandle* ph, int index) {
+  int count = 0;
+  lib_info* lib = ph->libs;
+  while (lib) {
+    if (count == index) {
+      return lib->name;
+    }
+    count++;
+    lib = lib->next;
+  }
+  return NULL;
+}
+
+// get base address of a lib
+uintptr_t get_lib_base(struct ps_prochandle* ph, int index) {
+  int count = 0;
+  lib_info* lib = ph->libs;
+  while (lib) {
+    if (count == index) {
+      return lib->base;
+    }
+    count++;
+    lib = lib->next;
+  }
+  return (uintptr_t)NULL;
+}
+
+bool find_lib(struct ps_prochandle* ph, const char *lib_name) {
+  lib_info *p = ph->libs;
+  while (p) {
+    if (strcmp(p->name, lib_name) == 0) {
+      return true;
+    }
+    p = p->next;
+  }
+  return false;
+}
+
+//--------------------------------------------------------------------------
+// proc service functions
+
+// ps_pglobal_lookup() looks up the symbol sym_name in the symbol table
+// of the load object object_name in the target process identified by ph.
+// It returns the symbol's value as an address in the target process in
+// *sym_addr.
+
+ps_err_e ps_pglobal_lookup(struct ps_prochandle *ph, const char *object_name,
+                    const char *sym_name, psaddr_t *sym_addr) {
+  *sym_addr = (psaddr_t) lookup_symbol(ph, object_name, sym_name);
+  return (*sym_addr ? PS_OK : PS_NOSYM);
+}
+
+// read "size" bytes info "buf" from address "addr"
+ps_err_e ps_pread(struct ps_prochandle *ph, psaddr_t  addr,
+                  void *buf, size_t size) {
+  return ph->ops->p_pread(ph, (uintptr_t) addr, buf, size)? PS_OK: PS_ERR;
+}
+
+// write "size" bytes of data to debuggee at address "addr"
+ps_err_e ps_pwrite(struct ps_prochandle *ph, psaddr_t addr,
+                   const void *buf, size_t size) {
+  return ph->ops->p_pwrite(ph, (uintptr_t)addr, buf, size)? PS_OK: PS_ERR;
+}
+
+// fill in ptrace_lwpinfo for lid
+ps_err_e ps_linfo(struct ps_prochandle *ph, lwpid_t lwp_id, void *linfo) {
+  return ph->ops->get_lwp_info(ph, lwp_id, linfo)? PS_OK: PS_ERR;
+}
+
+// needed for when libthread_db is compiled with TD_DEBUG defined
+void
+ps_plog (const char *format, ...)
+{
+  va_list alist;
+
+  va_start(alist, format);
+  vfprintf(stderr, format, alist);
+  va_end(alist);
+}
+
+#ifndef __APPLE__
+// ------------------------------------------------------------------------
+// Functions below this point are not yet implemented. They are here only
+// to make the linker happy.
+
+ps_err_e ps_lsetfpregs(struct ps_prochandle *ph, lwpid_t lid, const prfpregset_t *fpregs) {
+  print_debug("ps_lsetfpregs not implemented\n");
+  return PS_OK;
+}
+
+ps_err_e ps_lsetregs(struct ps_prochandle *ph, lwpid_t lid, const prgregset_t gregset) {
+  print_debug("ps_lsetregs not implemented\n");
+  return PS_OK;
+}
+
+ps_err_e  ps_lgetfpregs(struct  ps_prochandle  *ph,  lwpid_t lid, prfpregset_t *fpregs) {
+  print_debug("ps_lgetfpregs not implemented\n");
+  return PS_OK;
+}
+
+ps_err_e ps_lgetregs(struct ps_prochandle *ph, lwpid_t lid, prgregset_t gregset) {
+  print_debug("ps_lgetfpregs not implemented\n");
+  return PS_OK;
+}
+
+ps_err_e ps_lstop(struct ps_prochandle *ph, lwpid_t lid) {
+  print_debug("ps_lstop not implemented\n");
+  return PS_OK;
+}
+
+ps_err_e ps_pcontinue(struct ps_prochandle *ph) {
+  print_debug("ps_pcontinue not implemented\n");
+  return PS_OK;
+}
+#endif // __APPLE__