+/* Various addresses we might want to pull from the dynamic segment. */
+enum
+{
+ i_symtab,
+ i_strtab,
+ i_hash,
+ i_gnu_hash,
+ i_max
+};
+
+/* Translate pointers into file offsets. ADJUST is either zero
+ in case the dynamic segment wasn't adjusted or mod->main_bias.
+ Will set mod->symfile if the translated offsets can be used as
+ symbol table. */
+static void
+translate_offs (GElf_Addr adjust,
+ Dwfl_Module *mod, size_t phnum,
+ GElf_Addr addrs[i_max], GElf_Xword strsz,
+ GElf_Ehdr *ehdr)
+{
+ GElf_Off offs[i_max] = { 0, };
+ find_offsets (mod->main.elf, adjust, phnum, i_max, addrs, offs);
+
+ /* Figure out the size of the symbol table. */
+ if (offs[i_hash] != 0)
+ {
+ /* In the original format, .hash says the size of .dynsym. */
+
+ size_t entsz = SH_ENTSIZE_HASH (ehdr);
+ Elf_Data *data = elf_getdata_rawchunk (mod->main.elf,
+ offs[i_hash] + entsz, entsz,
+ (entsz == 4
+ ? ELF_T_WORD : ELF_T_XWORD));
+ if (data != NULL)
+ mod->syments = (entsz == 4
+ ? *(const GElf_Word *) data->d_buf
+ : *(const GElf_Xword *) data->d_buf);
+ }
+ if (offs[i_gnu_hash] != 0 && mod->syments == 0)
+ {
+ /* In the new format, we can derive it with some work. */
+
+ const struct
+ {
+ Elf32_Word nbuckets;
+ Elf32_Word symndx;
+ Elf32_Word maskwords;
+ Elf32_Word shift2;
+ } *header;
+
+ Elf_Data *data = elf_getdata_rawchunk (mod->main.elf, offs[i_gnu_hash],
+ sizeof *header, ELF_T_WORD);
+ if (data != NULL)
+ {
+ header = data->d_buf;
+ Elf32_Word nbuckets = header->nbuckets;
+ Elf32_Word symndx = header->symndx;
+ GElf_Off buckets_at = (offs[i_gnu_hash] + sizeof *header
+ + (gelf_getclass (mod->main.elf)
+ * sizeof (Elf32_Word)
+ * header->maskwords));
+
+ // elf_getdata_rawchunk takes a size_t, make sure it
+ // doesn't overflow.
+#if SIZE_MAX <= UINT32_MAX
+ if (nbuckets > SIZE_MAX / sizeof (Elf32_Word))
+ data = NULL;
+ else
+#endif
+ data = elf_getdata_rawchunk (mod->main.elf, buckets_at,
+ nbuckets * sizeof (Elf32_Word),
+ ELF_T_WORD);
+ if (data != NULL && symndx < nbuckets)
+ {
+ const Elf32_Word *const buckets = data->d_buf;
+ Elf32_Word maxndx = symndx;
+ for (Elf32_Word bucket = 0; bucket < nbuckets; ++bucket)
+ if (buckets[bucket] > maxndx)
+ maxndx = buckets[bucket];
+
+ GElf_Off hasharr_at = (buckets_at
+ + nbuckets * sizeof (Elf32_Word));
+ hasharr_at += (maxndx - symndx) * sizeof (Elf32_Word);
+ do
+ {
+ data = elf_getdata_rawchunk (mod->main.elf,
+ hasharr_at,
+ sizeof (Elf32_Word),
+ ELF_T_WORD);
+ if (data != NULL
+ && (*(const Elf32_Word *) data->d_buf & 1u))
+ {
+ mod->syments = maxndx + 1;
+ break;
+ }
+ ++maxndx;
+ hasharr_at += sizeof (Elf32_Word);
+ }
+ while (data != NULL);
+ }
+ }
+ }
+ if (offs[i_strtab] > offs[i_symtab] && mod->syments == 0)
+ mod->syments = ((offs[i_strtab] - offs[i_symtab])
+ / gelf_fsize (mod->main.elf,
+ ELF_T_SYM, 1, EV_CURRENT));
+
+ if (mod->syments > 0)
+ {
+ mod->symdata = elf_getdata_rawchunk (mod->main.elf,
+ offs[i_symtab],
+ gelf_fsize (mod->main.elf,
+ ELF_T_SYM,
+ mod->syments,
+ EV_CURRENT),
+ ELF_T_SYM);
+ if (mod->symdata != NULL)
+ {
+ mod->symstrdata = elf_getdata_rawchunk (mod->main.elf,
+ offs[i_strtab],
+ strsz,
+ ELF_T_BYTE);
+ if (mod->symstrdata == NULL)
+ mod->symdata = NULL;
+ }
+ if (mod->symdata == NULL)
+ mod->symerr = DWFL_E (LIBELF, elf_errno ());
+ else
+ {
+ mod->symfile = &mod->main;
+ mod->symerr = DWFL_E_NOERROR;
+ }
+ }
+}
+