1 /*
   2  * Copyright (c) 2012, 2019 SAP SE. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  *
  25  */
  26 
  27 #include <stdio.h>
  28 #include <string.h>
  29 #include <sys/ldr.h>
  30 #include <errno.h>
  31 
  32 #include "porting_aix.h"
  33 
  34 static unsigned char dladdr_buffer[0x8000];
  35 
  36 static void fill_dll_info(void) {
  37   int rc = loadquery(L_GETINFO,dladdr_buffer, sizeof(dladdr_buffer));
  38   if (rc == -1) {
  39     fprintf(stderr, "loadquery failed (%d %s)", errno, strerror(errno));
  40     fflush(stderr);
  41   }
  42 }
  43 
  44 static int dladdr_dont_reload(void* addr, Dl_info* info) {
  45   const struct ld_info* p = (struct ld_info*) dladdr_buffer;
  46   info->dli_fbase = 0; info->dli_fname = 0;
  47   info->dli_sname = 0; info->dli_saddr = 0;
  48   for (;;) {
  49     if (addr >= p->ldinfo_textorg &&
  50         addr < (((char*)p->ldinfo_textorg) + p->ldinfo_textsize)) {
  51       info->dli_fname = p->ldinfo_filename;
  52       info->dli_fbase = p->ldinfo_textorg;
  53       return 1; /* [sic] */
  54     }
  55     if (!p->ldinfo_next) {
  56       break;
  57     }
  58     p = (struct ld_info*)(((char*)p) + p->ldinfo_next);
  59   }
  60   return 0; /* [sic] */
  61 }
  62 
  63 #ifdef __cplusplus
  64 extern "C"
  65 #endif
  66 int dladdr(void *addr, Dl_info *info) {
  67   static int loaded = 0;
  68   if (!loaded) {
  69     fill_dll_info();
  70     loaded = 1;
  71   }
  72   if (!addr) {
  73     return 0;  /* [sic] */
  74   }
  75   /* Address could be AIX function descriptor? */
  76   void* const addr0 = *( (void**) addr );
  77   int rc = dladdr_dont_reload(addr, info);
  78   if (rc == 0) {
  79     rc = dladdr_dont_reload(addr0, info);
  80     if (rc == 0) { /* [sic] */
  81       fill_dll_info(); /* refill, maybe loadquery info is outdated */
  82       rc = dladdr_dont_reload(addr, info);
  83       if (rc == 0) {
  84         rc = dladdr_dont_reload(addr0, info);
  85       }
  86     }
  87   }
  88   return rc;
  89 }