http://sourceware.org/ml/gdb-patches/2013-05/msg00626.html Subject: [RFA 3/7] New gdbserver functionality --Kc9HNjpzOXVc7FFU Content-Type: text/plain; charset=us-ascii Content-Disposition: inline This patch updates gdbserver to allow arguments to be passed in the annex of qXfer:libraries-svr4:read to allow that function to transfer partial lists of libraries. The ability of gdbserver to support these arguments is indicated by a qSupported response containing "augmented-libraries-svr4-read+". --Kc9HNjpzOXVc7FFU Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="rtld-probes-3-gdbserver.patch" 2013-05-16 Gary Benson * server.c (handle_query): Add "augmented-libraries-svr4-read+" to qSupported response when appropriate. (handle_qxfer_libraries_svr4): Allow qXfer:libraries-svr4:read with nonzero-length annex. * linux-low.c (linux_qxfer_libraries_svr4): Parse and handle arguments supplied in annex. diff --git a/gdb/gdbserver/server.c b/gdb/gdbserver/server.c index 6bb36d8..0a8f68b 100644 --- a/gdb/gdbserver/server.c +++ b/gdb/gdbserver/server.c @@ -1115,8 +1115,7 @@ handle_qxfer_libraries_svr4 (const char *annex, if (writebuf != NULL) return -2; - if (annex[0] != '\0' || !target_running () - || the_target->qxfer_libraries_svr4 == NULL) + if (!target_running () || the_target->qxfer_libraries_svr4 == NULL) return -1; return the_target->qxfer_libraries_svr4 (annex, readbuf, writebuf, offset, len); @@ -1743,7 +1742,8 @@ handle_query (char *own_buf, int packet_len, int *new_packet_len_p) PBUFSIZ - 1); if (the_target->qxfer_libraries_svr4 != NULL) - strcat (own_buf, ";qXfer:libraries-svr4:read+"); + strcat (own_buf, ";qXfer:libraries-svr4:read+" + ";augmented-libraries-svr4-read+"); else { /* We do not have any hook to indicate whether the non-SVR4 target diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c index 72c51e0..beb3b8f 100644 --- a/gdb/gdbserver/linux-low.c +++ b/gdb/gdbserver/linux-low.c @@ -5677,6 +5677,12 @@ linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf, }; const struct link_map_offsets *lmo; unsigned int machine; + int ptr_size; + CORE_ADDR lm_addr = 0, lm_prev = 0; + int allocated = 1024; + char *p; + CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev; + int header_done = 0; if (writebuf != NULL) return -2; @@ -5687,128 +5693,146 @@ linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf, xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid); is_elf64 = elf_64_file_p (filename, &machine); lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets; + ptr_size = is_elf64 ? 8 : 4; - if (priv->r_debug == 0) - priv->r_debug = get_r_debug (pid, is_elf64); + if (annex[0] == '\0') + { + int r_version = 0; - /* We failed to find DT_DEBUG. Such situation will not change for this - inferior - do not retry it. Report it to GDB as E01, see for the reasons - at the GDB solib-svr4.c side. */ - if (priv->r_debug == (CORE_ADDR) -1) - return -1; + if (priv->r_debug == 0) + priv->r_debug = get_r_debug (pid, is_elf64); - if (priv->r_debug == 0) - { - document = xstrdup ("\n"); + /* We failed to find DT_DEBUG. Such situation will not change + for this inferior - do not retry it. Report it to GDB as + E01, see for the reasons at the GDB solib-svr4.c side. */ + if (priv->r_debug == (CORE_ADDR) -1) + return -1; + + if (priv->r_debug != 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); + } + else 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); + } + } } 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, "r_debug + lmo->r_version_offset, - (unsigned char *) &r_version, - sizeof (r_version)) != 0 - || r_version != 1) + while (annex[0] != '\0') { - warning ("unexpected r_debug version %d", r_version); - goto done; + const char *sep; + CORE_ADDR *addrp; + int len; + + sep = strchr (annex, '='); + if (!sep) + break; + + len = sep - annex; + if (len == 5 && !strncmp (annex, "start", 5)) + addrp = &lm_addr; + else if (len == 4 && !strncmp (annex, "prev", 4)) + addrp = &lm_prev; + else + { + annex = strchr (sep, ';'); + if (!annex) + break; + annex++; + continue; + } + + annex = decode_address_to_semicolon (addrp, sep + 1); } + } - if (read_one_ptr (priv->r_debug + lmo->r_map_offset, - &lm_addr, ptr_size) != 0) + document = xmalloc (allocated); + strcpy (document, "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 ("unable to read r_map from 0x%lx", - (long) priv->r_debug + lmo->r_map_offset); - goto done; + warning ("Corrupted shared library list: 0x%lx != 0x%lx", + (long) lm_prev, (long) l_prev); + break; } - 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) + /* 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') { - unsigned char libname[PATH_MAX]; + /* 6x the size for xml_escape_text below. */ + size_t len = 6 * strlen ((char *) libname); + char *name; - if (lm_prev != l_prev) + if (!header_done) { - warning ("Corrupted shared library list: 0x%lx != 0x%lx", - (long) lm_prev, (long) l_prev); - break; + /* Terminate `", - 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); + document = xrealloc (document, 2 * allocated); + allocated *= 2; + p = document + document_len; } - if (l_next == 0) - break; - - lm_prev = lm_addr; - lm_addr = l_next; + name = xml_escape_text ((char *) libname); + p += sprintf (p, "", + name, (unsigned long) lm_addr, + (unsigned long) l_addr, (unsigned long) l_ld); + free (name); } - done: - if (!header_done) + else if (lm_prev == 0) { - /* Empty list; terminate `"); + sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr); + p = p + strlen (p); } - else - strcpy (p, ""); + + lm_prev = lm_addr; + lm_addr = l_next; } + if (!header_done) + { + /* Empty list; terminate `"); + } + else + strcpy (p, ""); + document_len = strlen (document); if (offset < document_len) document_len -= offset; --Kc9HNjpzOXVc7FFU--