+static int
+linux_get_min_fast_tracepoint_insn_len (void)
+{
+ return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
+}
+
+/* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
+
+static int
+get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
+ CORE_ADDR *phdr_memaddr, int *num_phdr)
+{
+ char filename[PATH_MAX];
+ int fd;
+ const int auxv_size = is_elf64
+ ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
+ char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
+
+ xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
+
+ fd = open (filename, O_RDONLY);
+ if (fd < 0)
+ return 1;
+
+ *phdr_memaddr = 0;
+ *num_phdr = 0;
+ while (read (fd, buf, auxv_size) == auxv_size
+ && (*phdr_memaddr == 0 || *num_phdr == 0))
+ {
+ if (is_elf64)
+ {
+ Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
+
+ switch (aux->a_type)
+ {
+ case AT_PHDR:
+ *phdr_memaddr = aux->a_un.a_val;
+ break;
+ case AT_PHNUM:
+ *num_phdr = aux->a_un.a_val;
+ break;
+ }
+ }
+ else
+ {
+ Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
+
+ switch (aux->a_type)
+ {
+ case AT_PHDR:
+ *phdr_memaddr = aux->a_un.a_val;
+ break;
+ case AT_PHNUM:
+ *num_phdr = aux->a_un.a_val;
+ break;
+ }
+ }
+ }
+
+ close (fd);
+
+ if (*phdr_memaddr == 0 || *num_phdr == 0)
+ {
+ warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
+ "phdr_memaddr = %ld, phdr_num = %d",
+ (long) *phdr_memaddr, *num_phdr);
+ return 2;
+ }
+
+ return 0;
+}
+
+/* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
+
+static CORE_ADDR
+get_dynamic (const int pid, const int is_elf64)
+{
+ CORE_ADDR phdr_memaddr, relocation;
+ int num_phdr, i;
+ unsigned char *phdr_buf;
+ const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
+
+ if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
+ return 0;
+
+ gdb_assert (num_phdr < 100); /* Basic sanity check. */
+ phdr_buf = alloca (num_phdr * phdr_size);
+
+ if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
+ return 0;
+
+ /* Compute relocation: it is expected to be 0 for "regular" executables,
+ non-zero for PIE ones. */
+ relocation = -1;
+ for (i = 0; relocation == -1 && i < num_phdr; i++)
+ if (is_elf64)
+ {
+ Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
+
+ if (p->p_type == PT_PHDR)
+ relocation = phdr_memaddr - p->p_vaddr;
+ }
+ else
+ {
+ Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
+
+ if (p->p_type == PT_PHDR)
+ relocation = phdr_memaddr - p->p_vaddr;
+ }
+
+ if (relocation == -1)
+ {
+ /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
+ any real world executables, including PIE executables, have always
+ PT_PHDR present. PT_PHDR is not present in some shared libraries or
+ in fpc (Free Pascal 2.4) binaries but neither of those have a need for
+ or present DT_DEBUG anyway (fpc binaries are statically linked).
+
+ Therefore if there exists DT_DEBUG there is always also PT_PHDR.
+
+ GDB could find RELOCATION also from AT_ENTRY - e_entry. */
+
+ return 0;
+ }
+
+ for (i = 0; i < num_phdr; i++)
+ {
+ if (is_elf64)
+ {
+ Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
+
+ if (p->p_type == PT_DYNAMIC)
+ return p->p_vaddr + relocation;
+ }
+ else
+ {
+ Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
+
+ if (p->p_type == PT_DYNAMIC)
+ return p->p_vaddr + relocation;
+ }
+ }
+
+ return 0;
+}
+
+/* Return &_r_debug in the inferior, or -1 if not present. Return value
+ can be 0 if the inferior does not yet have the library list initialized. */
+
+static CORE_ADDR
+get_r_debug (const int pid, const int is_elf64)
+{
+ CORE_ADDR dynamic_memaddr;
+ const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
+ unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
+
+ dynamic_memaddr = get_dynamic (pid, is_elf64);
+ if (dynamic_memaddr == 0)
+ return (CORE_ADDR) -1;
+
+ while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
+ {
+ if (is_elf64)
+ {
+ Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
+
+ if (dyn->d_tag == DT_DEBUG)
+ return dyn->d_un.d_val;
+
+ if (dyn->d_tag == DT_NULL)
+ break;
+ }
+ else
+ {
+ Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
+
+ if (dyn->d_tag == DT_DEBUG)
+ return dyn->d_un.d_val;
+
+ if (dyn->d_tag == DT_NULL)
+ break;
+ }
+
+ dynamic_memaddr += dyn_size;
+ }
+
+ return (CORE_ADDR) -1;
+}
+
+/* Read one pointer from MEMADDR in the inferior. */
+
+static int
+read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
+{
+ *ptr = 0;
+ return linux_read_memory (memaddr, (unsigned char *) ptr, ptr_size);
+}
+
+struct link_map_offsets
+ {
+ /* Offset and size of r_debug.r_version. */
+ int r_version_offset;
+
+ /* Offset and size of r_debug.r_map. */
+ int r_map_offset;
+
+ /* Offset to l_addr field in struct link_map. */
+ int l_addr_offset;
+
+ /* Offset to l_name field in struct link_map. */
+ int l_name_offset;
+
+ /* Offset to l_ld field in struct link_map. */
+ int l_ld_offset;
+
+ /* Offset to l_next field in struct link_map. */
+ int l_next_offset;
+
+ /* Offset to l_prev field in struct link_map. */
+ int l_prev_offset;
+ };
+
+/* Construct qXfer:libraries:read reply. */
+
+static int
+linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
+ unsigned const char *writebuf,
+ CORE_ADDR offset, int len)
+{
+ char *document;
+ unsigned document_len;
+ struct process_info_private *const priv = current_process ()->private;
+ char filename[PATH_MAX];
+ int pid, is_elf64;
+
+ static const struct link_map_offsets lmo_32bit_offsets =
+ {
+ 0, /* r_version offset. */
+ 4, /* r_debug.r_map offset. */
+ 0, /* l_addr offset in link_map. */
+ 4, /* l_name offset in link_map. */
+ 8, /* l_ld offset in link_map. */
+ 12, /* l_next offset in link_map. */
+ 16 /* l_prev offset in link_map. */
+ };
+
+ static const struct link_map_offsets lmo_64bit_offsets =
+ {
+ 0, /* r_version offset. */
+ 8, /* r_debug.r_map offset. */
+ 0, /* l_addr offset in link_map. */
+ 8, /* l_name offset in link_map. */
+ 16, /* l_ld offset in link_map. */
+ 24, /* l_next offset in link_map. */
+ 32 /* l_prev offset in link_map. */
+ };
+ const struct link_map_offsets *lmo;
+
+ if (writebuf != NULL)
+ return -2;
+ if (readbuf == NULL)
+ return -1;
+
+ pid = lwpid_of (get_thread_lwp (current_inferior));
+ xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
+ is_elf64 = elf_64_file_p (filename);
+ lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
+
+ if (priv->r_debug == 0)
+ priv->r_debug = get_r_debug (pid, is_elf64);
+
+ if (priv->r_debug == (CORE_ADDR) -1 || priv->r_debug == 0)
+ {
+ document = xstrdup ("<library-list-svr4 version=\"1.0\"/>\n");
+ }
+ else
+ {
+ int allocated = 1024;
+ char *p;
+ const int ptr_size = is_elf64 ? 8 : 4;
+ CORE_ADDR lm_addr, lm_prev, l_name, l_addr, l_ld, l_next, l_prev;
+ int r_version, header_done = 0;
+
+ document = xmalloc (allocated);
+ strcpy (document, "<library-list-svr4 version=\"1.0\"");
+ p = document + strlen (document);
+
+ r_version = 0;
+ if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
+ (unsigned char *) &r_version,
+ sizeof (r_version)) != 0
+ || r_version != 1)
+ {
+ warning ("unexpected r_debug version %d", r_version);
+ goto done;
+ }
+
+ if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
+ &lm_addr, ptr_size) != 0)
+ {
+ warning ("unable to read r_map from 0x%lx",
+ (long) priv->r_debug + lmo->r_map_offset);
+ goto done;
+ }
+
+ lm_prev = 0;
+ while (read_one_ptr (lm_addr + lmo->l_name_offset,
+ &l_name, ptr_size) == 0
+ && read_one_ptr (lm_addr + lmo->l_addr_offset,
+ &l_addr, ptr_size) == 0
+ && read_one_ptr (lm_addr + lmo->l_ld_offset,
+ &l_ld, ptr_size) == 0
+ && read_one_ptr (lm_addr + lmo->l_prev_offset,
+ &l_prev, ptr_size) == 0
+ && read_one_ptr (lm_addr + lmo->l_next_offset,
+ &l_next, ptr_size) == 0)
+ {
+ unsigned char libname[PATH_MAX];
+
+ if (lm_prev != l_prev)
+ {
+ warning ("Corrupted shared library list: 0x%lx != 0x%lx",
+ (long) lm_prev, (long) l_prev);
+ break;
+ }
+
+ /* Not checking for error because reading may stop before
+ we've got PATH_MAX worth of characters. */
+ libname[0] = '\0';
+ linux_read_memory (l_name, libname, sizeof (libname) - 1);
+ libname[sizeof (libname) - 1] = '\0';
+ if (libname[0] != '\0')
+ {
+ /* 6x the size for xml_escape_text below. */
+ size_t len = 6 * strlen ((char *) libname);
+ char *name;
+
+ if (!header_done)
+ {
+ /* Terminate `<library-list-svr4'. */
+ *p++ = '>';
+ header_done = 1;
+ }
+
+ while (allocated < p - document + len + 200)
+ {
+ /* Expand to guarantee sufficient storage. */
+ uintptr_t document_len = p - document;
+
+ document = xrealloc (document, 2 * allocated);
+ allocated *= 2;
+ p = document + document_len;
+ }
+
+ name = xml_escape_text ((char *) libname);
+ p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
+ "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
+ name, (unsigned long) lm_addr,
+ (unsigned long) l_addr, (unsigned long) l_ld);
+ free (name);
+ }
+ else if (lm_prev == 0)
+ {
+ sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
+ p = p + strlen (p);
+ }
+
+ if (l_next == 0)
+ break;
+
+ lm_prev = lm_addr;
+ lm_addr = l_next;
+ }
+ done:
+ strcpy (p, "</library-list-svr4>");
+ }
+
+ document_len = strlen (document);
+ if (offset < document_len)
+ document_len -= offset;
+ else
+ document_len = 0;
+ if (len > document_len)
+ len = document_len;
+
+ memcpy (readbuf, document + offset, len);
+ xfree (document);
+
+ return len;
+}
+
projects / deliverable / binutils-gdb.git / blobdiff