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Diffstat (limited to 'gdb/solib-ia64-hpux.c')
| -rw-r--r-- | gdb/solib-ia64-hpux.c | 700 |
1 files changed, 700 insertions, 0 deletions
diff --git a/gdb/solib-ia64-hpux.c b/gdb/solib-ia64-hpux.c new file mode 100644 index 0000000..01d44a9 --- /dev/null +++ b/gdb/solib-ia64-hpux.c @@ -0,0 +1,700 @@ +/* Copyright (C) 2010 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include "defs.h" +#include "ia64-tdep.h" +#include "ia64-hpux-tdep.h" +#include "solib-ia64-hpux.h" +#include "solist.h" +#include "solib.h" +#include "target.h" +#include "gdbtypes.h" +#include "inferior.h" +#include "gdbcore.h" +#include "regcache.h" +#include "opcode/ia64.h" +#include "symfile.h" +#include "objfiles.h" +#include "elf-bfd.h" +#include "exceptions.h" + +/* Need to define the following macro in order to get the complete + load_module_desc struct definition in dlfcn.h Otherwise, it doesn't + match the size of the struct the loader is providing us during load + events. */ +#define _LOAD_MODULE_DESC_EXT + +#include <sys/ttrace.h> +#include <dlfcn.h> +#include <elf.h> +#include <service_mgr.h> + +/* The following is to have access to the definition of type load_info_t. */ +#include <crt0.h> + +/* The r32 pseudo-register number. + + Like all stacked registers, r32 is treated as a pseudo-register, + because it is not always available for read/write via the ttrace + interface. */ +/* This is a bit of a hack, as we duplicate something hidden inside + ia64-tdep.c, but oh well... */ +#define IA64_R32_PSEUDO_REGNUM (IA64_NAT127_REGNUM + 2) + +/* Our struct so_list private data structure. */ + +struct lm_info +{ + /* The shared library module descriptor. We extract this structure + from the loader at the time the shared library gets mapped. */ + struct load_module_desc module_desc; + + /* The text segment address as defined in the shared library object + (this is not the address where this segment got loaded). This + field is initially set to zero, and computed lazily. */ + CORE_ADDR text_start; + + /* The data segment address as defined in the shared library object + (this is not the address where this segment got loaded). This + field is initially set to zero, and computed lazily. */ + CORE_ADDR data_start; +}; + +/* The list of shared libraries currently mapped by the inferior. */ + +static struct so_list *so_list_head = NULL; + +/* Create a new so_list element. The result should be deallocated + when no longer in use. */ + +static struct so_list * +new_so_list (char *so_name, struct load_module_desc module_desc) +{ + struct so_list *new_so; + + new_so = (struct so_list *) XZALLOC (struct so_list); + new_so->lm_info = (struct lm_info *) XZALLOC (struct lm_info); + new_so->lm_info->module_desc = module_desc; + + strncpy (new_so->so_name, so_name, SO_NAME_MAX_PATH_SIZE - 1); + new_so->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; + strcpy (new_so->so_original_name, new_so->so_name); + + return new_so; +} + +/* Return non-zero if the instruction at the current PC is a breakpoint + part of the dynamic loading process. + + We identify such instructions by checking that the instruction at + the current pc is a break insn where no software breakpoint has been + inserted by us. We also verify that the operands have specific + known values, to be extra certain. + + PTID is the ptid of the thread that should be checked, but this + function also assumes that inferior_ptid is already equal to PTID. + Ideally, we would like to avoid the requirement on inferior_ptid, + but many routines still use the inferior_ptid global to access + the relevant thread's register and memory. We still have the ptid + as parameter to be able to pass it to the routines that do take a ptid + - that way we avoid increasing explicit uses of the inferior_ptid + global. */ + +static int +ia64_hpux_at_dld_breakpoint_1_p (ptid_t ptid) +{ + struct regcache *regcache = get_thread_regcache (ptid); + CORE_ADDR pc = regcache_read_pc (regcache); + struct address_space *aspace = get_regcache_aspace (regcache); + ia64_insn t0, t1, slot[3], template, insn; + int slotnum; + bfd_byte bundle[16]; + + /* If this is a regular breakpoint, then it can not be a dld one. */ + if (breakpoint_inserted_here_p (aspace, pc)) + return 0; + + slotnum = ((long) pc) & 0xf; + if (slotnum > 2) + internal_error (__FILE__, __LINE__, + "invalid slot (%d) for address %s", slotnum, + paddress (get_regcache_arch (regcache), pc)); + + pc -= (pc & 0xf); + read_memory (pc, bundle, sizeof (bundle)); + + /* bundles are always in little-endian byte order */ + t0 = bfd_getl64 (bundle); + t1 = bfd_getl64 (bundle + 8); + template = (t0 >> 1) & 0xf; + slot[0] = (t0 >> 5) & 0x1ffffffffffLL; + slot[1] = ((t0 >> 46) & 0x3ffff) | ((t1 & 0x7fffff) << 18); + slot[2] = (t1 >> 23) & 0x1ffffffffffLL; + + if (template == 2 && slotnum == 1) + { + /* skip L slot in MLI template: */ + slotnum = 2; + } + + insn = slot[slotnum]; + + return (insn == 0x1c0c9c0 /* break.i 0x070327 */ + || insn == 0x3c0c9c0); /* break.i 0x0f0327 */ +} + +/* Same as ia64_hpux_at_dld_breakpoint_1_p above, with the following + differences: It temporarily sets inferior_ptid to PTID, and also + contains any exception being raised. */ + +int +ia64_hpux_at_dld_breakpoint_p (ptid_t ptid) +{ + struct gdb_exception e; + ptid_t saved_ptid = inferior_ptid; + int result = 0; + + inferior_ptid = ptid; + TRY_CATCH (e, RETURN_MASK_ALL) + { + result = ia64_hpux_at_dld_breakpoint_1_p (ptid); + } + inferior_ptid = saved_ptid; + if (e.reason < 0) + warning (_("error while checking for dld breakpoint: %s"), e.message); + + return result; +} + +/* Handler for library load event: Read the information provided by + the loader, and then use it to read the shared library symbols. */ + +static void +ia64_hpux_handle_load_event (struct regcache *regcache) +{ + CORE_ADDR module_desc_addr; + ULONGEST module_desc_size; + CORE_ADDR so_path_addr; + char so_path[MAXPATHLEN]; + struct load_module_desc module_desc; + struct so_list *new_so; + + /* Extract the data provided by the loader as follow: + - r33: Address of load_module_desc structure + - r34: size of struct load_module_desc + - r35: Address of string holding shared library path + */ + regcache_cooked_read_unsigned (regcache, IA64_R32_PSEUDO_REGNUM + 1, + &module_desc_addr); + regcache_cooked_read_unsigned (regcache, IA64_R32_PSEUDO_REGNUM + 2, + &module_desc_size); + regcache_cooked_read_unsigned (regcache, IA64_R32_PSEUDO_REGNUM + 3, + &so_path_addr); + + if (module_desc_size != sizeof (struct load_module_desc)) + warning (_("load_module_desc size (%ld) != size returned by kernel (%s)"), + sizeof (struct load_module_desc), + pulongest (module_desc_size)); + + read_memory_string (so_path_addr, so_path, MAXPATHLEN); + read_memory (module_desc_addr, (gdb_byte *) &module_desc, + sizeof (module_desc)); + + /* Create a new so_list element and insert it at the start of our + so_list_head (we insert at the start of the list only because + it is less work compared to inserting it elsewhere). */ + new_so = new_so_list (so_path, module_desc); + new_so->next = so_list_head; + so_list_head = new_so; +} + +/* Update the value of the PC to point to the begining of the next + instruction bundle. */ + +static void +ia64_hpux_move_pc_to_next_bundle (struct regcache *regcache) +{ + CORE_ADDR pc = regcache_read_pc (regcache); + + pc -= pc & 0xf; + pc += 16; + ia64_write_pc (regcache, pc); +} + +/* Handle loader events. + + PTID is the ptid of the thread corresponding to the event being + handled. Similarly to ia64_hpux_at_dld_breakpoint_1_p, this + function assumes that inferior_ptid is set to PTID. */ + +static void +ia64_hpux_handle_dld_breakpoint_1 (ptid_t ptid) +{ + struct regcache *regcache = get_thread_regcache (ptid); + ULONGEST arg0; + + /* The type of event is provided by the loaded via r32. */ + regcache_cooked_read_unsigned (regcache, IA64_R32_PSEUDO_REGNUM, &arg0); + switch (arg0) + { + case BREAK_DE_SVC_LOADED: + /* Currently, the only service loads are uld and dld, + so we shouldn't need to do anything. Just ignore. */ + break; + case BREAK_DE_LIB_LOADED: + ia64_hpux_handle_load_event (regcache); + solib_add (NULL, 0, ¤t_target, auto_solib_add); + break; + case BREAK_DE_LIB_UNLOADED: + case BREAK_DE_LOAD_COMPLETE: + case BREAK_DE_BOR: + /* Ignore for now. */ + break; + } + + /* Now that we have handled the event, we can move the PC to + the next instruction bundle, past the break instruction. */ + ia64_hpux_move_pc_to_next_bundle (regcache); +} + +/* Same as ia64_hpux_handle_dld_breakpoint_1 above, with the following + differences: This function temporarily sets inferior_ptid to PTID, + and also contains any exception. */ + +void +ia64_hpux_handle_dld_breakpoint (ptid_t ptid) +{ + struct gdb_exception e; + ptid_t saved_ptid = inferior_ptid; + + inferior_ptid = ptid; + TRY_CATCH (e, RETURN_MASK_ALL) + { + ia64_hpux_handle_dld_breakpoint_1 (ptid); + } + inferior_ptid = saved_ptid; + if (e.reason < 0) + warning (_("error detected while handling dld breakpoint: %s"), e.message); +} + +/* Find the address of the code and data segments in ABFD, and update + TEXT_START and DATA_START accordingly. */ + +static void +ia64_hpux_find_start_vma (bfd *abfd, CORE_ADDR *text_start, + CORE_ADDR *data_start) +{ + Elf_Internal_Ehdr *i_ehdrp = elf_elfheader (abfd); + Elf64_Phdr phdr; + int i; + + *text_start = 0; + *data_start = 0; + + if (bfd_seek (abfd, i_ehdrp->e_phoff, SEEK_SET) == -1) + error (_("invalid program header offset in %s"), abfd->filename); + + for (i = 0; i < i_ehdrp->e_phnum; i++) + { + if (bfd_bread ((PTR) & phdr, sizeof (phdr), abfd) != sizeof (phdr)) + error (_("failed to read segment %d in %s"), i, abfd->filename); + + if (phdr.p_flags & PF_X + && (*text_start == 0 || phdr.p_vaddr < *text_start)) + *text_start = phdr.p_vaddr; + + if (phdr.p_flags & PF_W + && (*data_start == 0 || phdr.p_vaddr < *data_start)) + *data_start = phdr.p_vaddr; + } +} + +/* The "relocate_section_addresses" target_so_ops routine for ia64-hpux. */ + +static void +ia64_hpux_relocate_section_addresses (struct so_list *so, + struct target_section *sec) +{ + CORE_ADDR offset = 0; + + /* If we haven't computed the text & data segment addresses, do so now. + We do this here, because we now have direct access to the associated + bfd, whereas we would have had to open our own if we wanted to do it + while processing the library-load event. */ + if (so->lm_info->text_start == 0 && so->lm_info->data_start == 0) + ia64_hpux_find_start_vma (sec->bfd, &so->lm_info->text_start, + &so->lm_info->data_start); + + /* Determine the relocation offset based on which segment + the section belongs to. */ + if ((so->lm_info->text_start < so->lm_info->data_start + && sec->addr < so->lm_info->data_start) + || (so->lm_info->text_start > so->lm_info->data_start + && sec->addr >= so->lm_info->text_start)) + offset = so->lm_info->module_desc.text_base - so->lm_info->text_start; + else if ((so->lm_info->text_start < so->lm_info->data_start + && sec->addr >= so->lm_info->data_start) + || (so->lm_info->text_start > so->lm_info->data_start + && sec->addr < so->lm_info->text_start)) + offset = so->lm_info->module_desc.data_base - so->lm_info->data_start; + + /* And now apply the relocation. */ + sec->addr += offset; + sec->endaddr += offset; + + /* Best effort to set addr_high/addr_low. This is used only by + 'info sharedlibrary'. */ + if (so->addr_low == 0 || sec->addr < so->addr_low) + so->addr_low = sec->addr; + + if (so->addr_high == 0 || sec->endaddr > so->addr_high) + so->addr_high = sec->endaddr; +} + +/* The "free_so" target_so_ops routine for ia64-hpux. */ + +static void +ia64_hpux_free_so (struct so_list *so) +{ + xfree (so->lm_info); +} + +/* The "clear_solib" target_so_ops routine for ia64-hpux. */ + +static void +ia64_hpux_clear_solib (void) +{ + struct so_list *so; + + while (so_list_head != NULL) + { + so = so_list_head; + so_list_head = so_list_head->next; + + ia64_hpux_free_so (so); + xfree (so); + } +} + +/* Assuming the inferior just stopped on an EXEC event, return + the address of the load_info_t structure. */ + +static CORE_ADDR +ia64_hpux_get_load_info_addr (void) +{ + struct type *data_ptr_type = builtin_type (target_gdbarch)->builtin_data_ptr; + CORE_ADDR addr; + int status; + + /* The address of the load_info_t structure is stored in the 4th + argument passed to the initial thread of the process (in other + words, in argv[3]). So get the address of these arguments, + and extract the 4th one. */ + status = ttrace (TT_PROC_GET_ARGS, ptid_get_pid (inferior_ptid), + 0, (uintptr_t) &addr, sizeof (CORE_ADDR), 0); + if (status == -1 && errno) + perror_with_name (_("Unable to get argument list")); + return (read_memory_typed_address (addr + 3 * 8, data_ptr_type)); +} + +/* A structure used to aggregate some information extracted from + the dynamic section of the main executable. */ + +struct dld_info +{ + long long dld_flags; + CORE_ADDR load_map; +}; + +/* Scan the ".dynamic" section referenced by ABFD and DYN_SECT, + and extract the information needed to fill in INFO. */ + +static void +ia64_hpux_read_dynamic_info (struct gdbarch *gdbarch, bfd *abfd, + asection *dyn_sect, struct dld_info *info) +{ + int sect_size; + char *buf; + char *buf_end; + + /* Make sure that info always has initialized data, even if we fail + to read the syn_sect section. */ + memset (info, 0, sizeof (struct dld_info)); + + sect_size = bfd_section_size (abfd, dyn_sect); + buf = alloca (sect_size); + buf_end = buf + sect_size; + + if (bfd_seek (abfd, dyn_sect->filepos, SEEK_SET) != 0 + || bfd_bread (buf, sect_size, abfd) != sect_size) + error (_("failed to read contents of .dynamic section")); + + for (; buf < buf_end; buf += sizeof (Elf64_Dyn)) + { + Elf64_Dyn *dynp = (Elf64_Dyn *) buf; + Elf64_Sxword d_tag; + + d_tag = bfd_h_get_64 (abfd, &dynp->d_tag); + switch (d_tag) + { + case DT_HP_DLD_FLAGS: + info->dld_flags = bfd_h_get_64 (abfd, &dynp->d_un); + break; + + case DT_HP_LOAD_MAP: + { + CORE_ADDR load_map_addr = bfd_h_get_64 (abfd, &dynp->d_un.d_ptr); + + if (target_read_memory (load_map_addr, (char *) &info->load_map, + sizeof (info->load_map)) != 0) + error (_("failed to read load map at %s"), + paddress (gdbarch, load_map_addr)); + } + break; + } + } +} + +/* Wrapper around target_read_memory used with libdl. */ + +static void * +ia64_hpux_read_tgt_mem (void *buffer, uint64_t ptr, size_t bufsiz, int ident) +{ + if (target_read_memory (ptr, (gdb_byte *) buffer, bufsiz) != 0) + return 0; + else + return buffer; +} + +/* Create a new so_list object for a shared library, and store that + new so_list object in our SO_LIST_HEAD list. + + SO_INDEX is an index specifying the placement of the loaded shared + library in the dynamic loader's search list. Normally, this index + is strictly positive, but an index of -1 refers to the loader itself. + + Return nonzero if the so_list object could be created. A null + return value with a positive SO_INDEX normally means that there are + no more entries in the dynamic loader's search list at SO_INDEX or + beyond. */ + +static int +ia64_hpux_add_so_from_dld_info (struct dld_info info, int so_index) +{ + struct load_module_desc module_desc; + uint64_t so_handle; + char *so_path; + struct so_list *so; + + so_handle = dlgetmodinfo (so_index, &module_desc, sizeof (module_desc), + ia64_hpux_read_tgt_mem, 0, info.load_map); + + if (so_handle == 0) + /* No such entry. We probably reached the end of the list. */ + return 0; + + so_path = dlgetname (&module_desc, sizeof (module_desc), + ia64_hpux_read_tgt_mem, 0, info.load_map); + if (so_path == NULL) + { + /* Should never happen, but let's not crash if it does. */ + warning (_("unable to get shared library name, symbols not loaded")); + return 0; + } + + /* Create a new so_list and insert it at the start of our list. + The order is not extremely important, but it's less work to do so + at the end of the list. */ + so = new_so_list (so_path, module_desc); + so->next = so_list_head; + so_list_head = so; + + return 1; +} + +/* Assuming we just attached to a process, update our list of shared + libraries (SO_LIST_HEAD) as well as GDB's list. */ + +static void +ia64_hpux_solib_add_after_attach (void) +{ + bfd *abfd; + asection *dyn_sect; + struct dld_info info; + int i; + + if (symfile_objfile == NULL) + return; + + abfd = symfile_objfile->obfd; + dyn_sect = bfd_get_section_by_name (abfd, ".dynamic"); + + if (dyn_sect == NULL || bfd_section_size (abfd, dyn_sect) == 0) + return; + + ia64_hpux_read_dynamic_info (get_objfile_arch (symfile_objfile), abfd, + dyn_sect, &info); + + if ((info.dld_flags & DT_HP_DEBUG_PRIVATE) == 0) + { + warning (_( +"The shared libraries were not privately mapped; setting a breakpoint\n\ +in a shared library will not work until you rerun the program.\n\ +Use the following command to enable debugging of shared libraries.\n\ +chatr +dbg enable a.out")); + } + + /* Read the symbols of the dynamic loader (dld.so). */ + ia64_hpux_add_so_from_dld_info (info, -1); + + /* Read the symbols of all the other shared libraries. */ + for (i = 1; ; i++) + if (!ia64_hpux_add_so_from_dld_info (info, i)) + break; /* End of list. */ + + /* Resync the library list at the core level. */ + solib_add (NULL, 1, ¤t_target, auto_solib_add); +} + +/* The "create_inferior_hook" target_so_ops routine for ia64-hpux. */ + +static void +ia64_hpux_solib_create_inferior_hook (int from_tty) +{ + CORE_ADDR load_info_addr; + load_info_t load_info; + + /* Initially, we were thinking about adding a check that the program + (accessible through symfile_objfile) was linked against some shared + libraries, by searching for a ".dynamic" section. However, could + this break in the case of a statically linked program that later + uses dlopen? Programs that are fully statically linked are very + rare, and we will worry about them when we encounter one that + causes trouble. */ + + /* Set the LI_TRACE flag in the load_info_t structure. This enables + notifications when shared libraries are being mapped. */ + load_info_addr = ia64_hpux_get_load_info_addr (); + read_memory (load_info_addr, (gdb_byte *) &load_info, sizeof (load_info)); + load_info.li_flags |= LI_TRACE; + write_memory (load_info_addr, (gdb_byte *) &load_info, sizeof (load_info)); + + /* If we just attached to our process, some shard libraries have + already been mapped. Find which ones they are... */ + if (current_inferior ()->attach_flag) + ia64_hpux_solib_add_after_attach (); +} + +/* The "special_symbol_handling" target_so_ops routine for ia64-hpux. */ + +static void +ia64_hpux_special_symbol_handling (void) +{ + /* Nothing to do. */ +} + +/* The "current_sos" target_so_ops routine for ia64-hpux. */ + +static struct so_list * +ia64_hpux_current_sos (void) +{ + /* Return a deep copy of our own list. */ + struct so_list *new_head = NULL, *prev_new_so = NULL; + struct so_list *our_so; + + for (our_so = so_list_head; our_so != NULL; our_so = our_so->next) + { + struct so_list *new_so; + + new_so = new_so_list (our_so->so_name, our_so->lm_info->module_desc); + if (prev_new_so != NULL) + prev_new_so->next = new_so; + prev_new_so = new_so; + if (new_head == NULL) + new_head = new_so; + } + + return new_head; +} + +/* The "open_symbol_file_object" target_so_ops routine for ia64-hpux. */ + +static int +ia64_hpux_open_symbol_file_object (void *from_ttyp) +{ + return 0; +} + +/* The "in_dynsym_resolve_code" target_so_ops routine for ia64-hpux. */ + +static int +ia64_hpux_in_dynsym_resolve_code (CORE_ADDR pc) +{ + return 0; +} + +/* If FADDR is the address of a function inside one of the shared + libraries, return the shared library linkage address. */ + +CORE_ADDR +ia64_hpux_get_solib_linkage_addr (CORE_ADDR faddr) +{ + struct so_list *so = so_list_head; + + while (so != NULL) + { + struct load_module_desc module_desc = so->lm_info->module_desc; + + if (module_desc.text_base <= faddr + && (module_desc.text_base + module_desc.text_size) > faddr) + return module_desc.linkage_ptr; + + so = so->next; + } + + return 0; +} + +/* Create a new target_so_ops structure suitable for ia64-hpux, and + return its address. */ + +static struct target_so_ops * +ia64_hpux_target_so_ops (void) +{ + struct target_so_ops *ops = XZALLOC (struct target_so_ops); + + ops->relocate_section_addresses = ia64_hpux_relocate_section_addresses; + ops->free_so = ia64_hpux_free_so; + ops->clear_solib = ia64_hpux_clear_solib; + ops->solib_create_inferior_hook = ia64_hpux_solib_create_inferior_hook; + ops->special_symbol_handling = ia64_hpux_special_symbol_handling; + ops->current_sos = ia64_hpux_current_sos; + ops->open_symbol_file_object = ia64_hpux_open_symbol_file_object; + ops->in_dynsym_resolve_code = ia64_hpux_in_dynsym_resolve_code; + ops->bfd_open = solib_bfd_open; + + return ops; +} + +/* Prevent warning from -Wmissing-prototypes. */ +void _initialize_solib_ia64_hpux (void); + +void +_initialize_solib_ia64_hpux (void) +{ + ia64_hpux_so_ops = ia64_hpux_target_so_ops (); +} |