diff options
Diffstat (limited to 'gdb/somsolib.c')
| -rw-r--r-- | gdb/somsolib.c | 124 |
1 files changed, 112 insertions, 12 deletions
diff --git a/gdb/somsolib.c b/gdb/somsolib.c index 595752c..2d232b3 100644 --- a/gdb/somsolib.c +++ b/gdb/somsolib.c @@ -1,5 +1,5 @@ /* Handle HP SOM shared libraries for GDB, the GNU Debugger. - Copyright 1993 Free Software Foundation, Inc. + Copyright 1993, 1996 Free Software Foundation, Inc. This file is part of GDB. @@ -41,11 +41,7 @@ and by Cygnus Support. */ * Most of this code should work for hp300 shared libraries. Does anyone care enough to weed out any SOM-isms. - * Do we need/want a command to load a shared library? - - * Support for hpux8 dynamic linker. - - * Support for tracking user calls to dld_load, dld_unload. */ + * Support for hpux8 dynamic linker. */ /* The basic structure which describes a dynamically loaded object. This data structure is private to the dynamic linker and isn't found in @@ -499,9 +495,10 @@ void som_solib_create_inferior_hook() { struct minimal_symbol *msymbol; - unsigned int dld_flags, status; + unsigned int dld_flags, status, have_endo; asection *shlib_info; char shadow_contents[BREAKPOINT_MAX], buf[4]; + struct objfile *objfile; CORE_ADDR anaddr; if (symfile_objfile == NULL) @@ -516,12 +513,106 @@ som_solib_create_inferior_hook() if (bfd_section_size (symfile_objfile->obfd, shlib_info) == 0) return; + have_endo = 0; + /* Slam the pid of the process into __d_pid; failing is only a warning! */ + msymbol = lookup_minimal_symbol ("__d_pid", NULL, symfile_objfile); + if (msymbol == NULL) + { + warning ("Unable to find __d_pid symbol in object file.\n"); + warning ("Suggest linking with /usr/lib/end.o.\n"); + warning ("GDB will be unable to track shl_load/shl_unload calls\n"); + goto keep_going; + } + + anaddr = SYMBOL_VALUE_ADDRESS (msymbol); + store_unsigned_integer (buf, 4, inferior_pid); + status = target_write_memory (anaddr, buf, 4); + if (status != 0) + { + warning ("Unable to write __d_pid\n"); + warning ("Suggest linking with /usr/lib/end.o.\n"); + warning ("GDB will be unable to track shl_load/shl_unload calls\n"); + goto keep_going; + } + + /* Get the value of _DLD_HOOK (an export stub) and put it in __dld_hook; + This will force the dynamic linker to call __d_trap when significant + events occur. */ + msymbol = lookup_minimal_symbol ("_DLD_HOOK", NULL, symfile_objfile); + if (msymbol == NULL) + { + warning ("Unable to find _DLD_HOOK symbol in object file.\n"); + warning ("Suggest linking with /usr/lib/end.o.\n"); + warning ("GDB will be unable to track shl_load/shl_unload calls\n"); + goto keep_going; + } + anaddr = SYMBOL_VALUE_ADDRESS (msymbol); + + /* Grrr, this might not be an export symbol! We have to find the + export stub. */ + ALL_OBJFILES (objfile) + { + struct unwind_table_entry *u; + + /* What a crock. */ + msymbol = lookup_minimal_symbol_solib_trampoline (SYMBOL_NAME (msymbol), + NULL, objfile); + /* Found a symbol with the right name. */ + if (msymbol) + { + struct unwind_table_entry *u; + /* It must be a shared library trampoline. */ + if (SYMBOL_TYPE (msymbol) != mst_solib_trampoline) + continue; + + /* It must also be an export stub. */ + u = find_unwind_entry (SYMBOL_VALUE (msymbol)); + if (!u || u->stub_type != EXPORT) + continue; + + /* OK. Looks like the correct import stub. */ + anaddr = SYMBOL_VALUE (msymbol); + break; + } + } + store_unsigned_integer (buf, 4, anaddr); + + msymbol = lookup_minimal_symbol ("__dld_hook", NULL, symfile_objfile); + if (msymbol == NULL) + { + warning ("Unable to find __dld_hook symbol in object file.\n"); + warning ("Suggest linking with /usr/lib/end.o.\n"); + warning ("GDB will be unable to track shl_load/shl_unload calls\n"); + goto keep_going; + } + anaddr = SYMBOL_VALUE_ADDRESS (msymbol); + status = target_write_memory (anaddr, buf, 4); + + /* Now set a shlib_event breakpoint at __d_trap so we can track + significant shared library events. */ + msymbol = lookup_minimal_symbol ("__d_trap", NULL, symfile_objfile); + if (msymbol == NULL) + { + warning ("Unable to find __dld_d_trap symbol in object file.\n"); + warning ("Suggest linking with /usr/lib/end.o.\n"); + warning ("GDB will be unable to track shl_load/shl_unload calls\n"); + goto keep_going; + } + create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol)); + + /* We have all the support usually found in end.o, so we can track + shl_load and shl_unload calls. */ + have_endo = 1; + +keep_going: + /* Get the address of __dld_flags, if no such symbol exists, then we can not debug the shared code. */ msymbol = lookup_minimal_symbol ("__dld_flags", NULL, NULL); if (msymbol == NULL) { error ("Unable to find __dld_flags symbol in object file.\n"); + goto keep_going; return; } @@ -536,7 +627,7 @@ som_solib_create_inferior_hook() dld_flags = extract_unsigned_integer (buf, 4); /* Turn on the flags we care about. */ - dld_flags |= 0x5; + dld_flags |= (0x5 | (have_endo << 1)); store_unsigned_integer (buf, 4, dld_flags); status = target_write_memory (anaddr, buf, 4); if (status != 0) @@ -545,7 +636,15 @@ som_solib_create_inferior_hook() return; } - /* Now find the address of _start and set a breakpoint there. */ + /* Now find the address of _start and set a breakpoint there. + We still need this code for two reasons: + + * Not all sites have /usr/lib/end.o, so it's not always + possible to track the dynamic linker's events. + + * At this time no events are triggered for shared libraries + loaded at startup time (what a crock). */ + msymbol = lookup_minimal_symbol ("_start", NULL, symfile_objfile); if (msymbol == NULL) { @@ -592,7 +691,7 @@ som_solib_create_inferior_hook() return; } - if (auto_solib_add_at_startup) + if (auto_solib_add) som_solib_add ((char *) 0, 0, (struct target_ops *) 0); } @@ -728,10 +827,11 @@ _initialize_som_solib () "Status of loaded shared object libraries."); add_show_from_set (add_set_cmd ("auto-solib-add", class_support, var_zinteger, - (char *) &auto_solib_add_at_startup, + (char *) &auto_solib_add, "Set autoloading of shared library symbols at startup.\n\ If nonzero, symbols from all shared object libraries will be loaded\n\ -automatically when the inferior begins execution. Otherwise, symbols\n\ +automatically when the inferior begins execution or when the dynamic linker\n\ +informs gdb that a new library has been loaded. Otherwise, symbols\n\ must be loaded manually, using `sharedlibrary'.", &setlist), &showlist); |