contrib/elftoolchain/libdwarf/libdwarf_loclist.c

   1 /*-
   2  * Copyright (c) 2009,2011 Kai Wang
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  */
  26
  27 #include "_libdwarf.h"
  28
  29 ELFTC_VCSID("$Id: libdwarf_loclist.c 3061 2014-06-02 00:42:41Z kaiwang27 $");
  30
  31 static int
  32 _dwarf_loclist_add_locdesc(Dwarf_Debug dbg, Dwarf_CU cu, Dwarf_Section *ds,
  33     Dwarf_Unsigned *off, Dwarf_Locdesc **ld, Dwarf_Signed *ldlen,
  34     Dwarf_Unsigned *total_len, Dwarf_Error *error)
  35 {
  36         uint64_t start, end;
  37         int i, len, ret;
  38
  39         if (total_len != NULL)
  40                 *total_len = 0;
  41
  42         for (i = 0; *off < ds->ds_size; i++) {
  43                 start = dbg->read(ds->ds_data, off, cu->cu_pointer_size);
  44                 end = dbg->read(ds->ds_data, off, cu->cu_pointer_size);
  45                 if (ld != NULL) {
  46                         ld[i]->ld_lopc = start;
  47                         ld[i]->ld_hipc = end;
  48                 }
  49
  50                 if (total_len != NULL)
  51                         *total_len += 2 * cu->cu_pointer_size;
  52
  53                 /* Check if it is the end entry. */
  54                 if (start == 0 && end ==0) {
  55                         i++;
  56                         break;
  57                 }
  58
  59                 /* Check if it is base-select entry. */
  60                 if ((cu->cu_pointer_size == 4 && start == ~0U) ||
  61                     (cu->cu_pointer_size == 8 && start == ~0ULL))
  62                         continue;
  63
  64                 /* Otherwise it's normal entry. */
  65                 len = dbg->read(ds->ds_data, off, 2);
  66                 if (*off + len > ds->ds_size) {
  67                         DWARF_SET_ERROR(dbg, error,
  68                             DW_DLE_DEBUG_LOC_SECTION_SHORT);
  69                         return (DW_DLE_DEBUG_LOC_SECTION_SHORT);
  70                 }
  71
  72                 if (total_len != NULL)
  73                         *total_len += len;
  74
  75                 if (ld != NULL) {
  76                         ret = _dwarf_loc_fill_locdesc(dbg, ld[i],
  77                             ds->ds_data + *off, len, cu->cu_pointer_size,
  78                             cu->cu_length_size == 4 ? 4 : 8, cu->cu_version,
  79                             error);
  80                         if (ret != DW_DLE_NONE)
  81                                 return (ret);
  82                 }
  83
  84                 *off += len;
  85         }
  86
  87         if (ldlen != NULL)
  88                 *ldlen = i;
  89
  90         return (DW_DLE_NONE);
  91 }
  92
  93 int
  94 _dwarf_loclist_find(Dwarf_Debug dbg, Dwarf_CU cu, uint64_t lloff,
  95     Dwarf_Locdesc ***ret_llbuf, Dwarf_Signed *listlen,
  96     Dwarf_Unsigned *entry_len, Dwarf_Error *error)
  97 {
  98         Dwarf_Locdesc **llbuf;
  99         Dwarf_Section *ds;
 100         Dwarf_Signed ldlen;
 101         Dwarf_Unsigned off;
 102         int i, ret;
 103
 104         if ((ds = _dwarf_find_section(dbg, ".debug_loc")) == NULL) {
 105                 DWARF_SET_ERROR(dbg, error, DW_DLE_NO_ENTRY);
 106                 return (DW_DLE_NO_ENTRY);
 107         }
 108
 109         if (lloff >= ds->ds_size) {
 110                 DWARF_SET_ERROR(dbg, error, DW_DLE_NO_ENTRY);
 111                 return (DW_DLE_NO_ENTRY);
 112         }
 113
 114         /* Get the number of locdesc the first round. */
 115         off = lloff;
 116         ret = _dwarf_loclist_add_locdesc(dbg, cu, ds, &off, NULL, &ldlen,
 117             NULL, error);
 118         if (ret != DW_DLE_NONE)
 119                 return (ret);
 120
 121         if (ldlen == 0)
 122                 return (DW_DLE_NO_ENTRY);
 123
 124         /*
 125          * Dwarf_Locdesc list memory is allocated in this way (one more level
 126          * of indirect) to make the loclist API be compatible with SGI libdwarf.
 127          */
 128         if ((llbuf = calloc(ldlen, sizeof(Dwarf_Locdesc *))) == NULL) {
 129                 DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
 130                 return (DW_DLE_MEMORY);
 131         }
 132         for (i = 0; i < ldlen; i++) {
 133                 if ((llbuf[i] = calloc(1, sizeof(Dwarf_Locdesc))) == NULL) {
 134                         DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
 135                         ret = DW_DLE_MEMORY;
 136                         goto fail_cleanup;
 137                 }
 138         }
 139
 140         off = lloff;
 141
 142         /* Fill in locdesc. */
 143         ret = _dwarf_loclist_add_locdesc(dbg, cu, ds, &off, llbuf, NULL,
 144             entry_len, error);
 145         if (ret != DW_DLE_NONE)
 146                 goto fail_cleanup;
 147
 148         *ret_llbuf = llbuf;
 149         *listlen = ldlen;
 150
 151         return (DW_DLE_NONE);
 152
 153 fail_cleanup:
 154
 155         if (llbuf != NULL) {
 156                 for (i = 0; i < ldlen; i++) {
 157                         if (llbuf[i]->ld_s)
 158                                 free(llbuf[i]->ld_s);
 159                         free(llbuf[i]);
 160                 }
 161                 free(llbuf);
 162         }
 163
 164         return (ret);
 165 }