agent/src/os/bsd/libproc_impl.c

8003348: SA can not read core file on OS X

*** 19,41 ****
   * 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 <stdarg.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <fcntl.h>
- #include <thread_db.h>
  #include "libproc_impl.h"
  
  static const char* alt_root = NULL;
  static int alt_root_len = -1;
  
  #define SA_ALTROOT "SA_ALTROOT"
  
  static void init_alt_root() {
     if (alt_root_len == -1) {
        alt_root = getenv(SA_ALTROOT);
        if (alt_root) {
           alt_root_len = strlen(alt_root);
--- 19,39 ----
   * 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);
*** 48,61 ****
  int pathmap_open(const char* name) {
     int fd;
     char alt_path[PATH_MAX + 1];
  
     init_alt_root();
-    fd = open(name, O_RDONLY);
-    if (fd >= 0) {
-       return fd;
-    }
  
     if (alt_root_len > 0) {
        strcpy(alt_path, alt_root);
        strcat(alt_path, name);
        fd = open(alt_path, O_RDONLY);
--- 46,55 ----
*** 71,82 ****
           if (fd >= 0) {
              print_debug("path %s substituted for %s\n", alt_path, name);
              return fd;
           }
        }
     }
! 
     return -1;
  }
  
  static bool _libsaproc_debug;
  
--- 65,80 ----
        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;
  
*** 101,148 ****
  
  bool is_debug() {
     return _libsaproc_debug;
  }
  
  // initialize libproc
  bool init_libproc(bool debug) {
-    // init debug mode
     _libsaproc_debug = debug;
! 
     // initialize the thread_db library
     if (td_init() != TD_OK) {
       print_debug("libthread_db's td_init failed\n");
       return false;
     }
! 
     return true;
  }
  
! static 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;
     }
  }
  
! static void destroy_thread_info(struct ps_prochandle* ph) {
!    thread_info* thr = ph->threads;
     while (thr) {
!      thread_info *next = thr->next;
       free(thr);
!      thr = next;
     }
  }
  
  // ps_prochandle cleanup
- 
- // 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);
--- 99,201 ----
  
  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);
*** 153,162 ****
--- 206,216 ----
    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;
    }
*** 172,208 ****
        }
     } else {
        newlib->fd = fd;
     }
  
     // 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;
     }
  
     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 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,
--- 226,270 ----
      }
    } 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,
*** 226,236 ****
     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) {
--- 288,297 ----
*** 241,253 ****
     }
     return NULL;
  }
  
  // add a thread to ps_prochandle
! thread_info* add_thread_info(struct ps_prochandle* ph, pthread_t pthread_id, lwpid_t lwp_id) {
!    thread_info* newthr;
!    if ( (newthr = (thread_info*) calloc(1, sizeof(thread_info))) == NULL) {
        print_debug("can't allocate memory for thread_info\n");
        return NULL;
     }
  
     // initialize thread info
--- 302,314 ----
    }
    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
*** 259,269 ****
     ph->threads = newthr;
     ph->num_threads++;
     return newthr;
  }
  
! 
  // struct used for client data from thread_db callback
  struct thread_db_client_data {
     struct ps_prochandle* ph;
     thread_info_callback callback;
  };
--- 320,330 ----
    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;
  };
*** 312,341 ****
    // delete thread agent
    td_ta_delete(thread_agent);
    return true;
  }
  
  
  // 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;
!    thread_info* thr = ph->threads;
     while (thr) {
        if (count == index) {
           return thr->lwp_id;
        }
        count++;
        thr = thr->next;
     }
!    return -1;
  }
  
  // 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);
  }
  
--- 373,439 ----
    // 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);
  }
  
*** 423,432 ****
--- 521,531 ----
    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) {
*** 456,460 ****
--- 555,560 ----
  
  ps_err_e ps_pcontinue(struct ps_prochandle *ph) {
    print_debug("ps_pcontinue not implemented\n");
    return PS_OK;
  }
+ #endif // __APPLE__