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Diffstat (limited to 'gdb/solib-dsbt.c')
-rw-r--r--gdb/solib-dsbt.c147
1 files changed, 28 insertions, 119 deletions
diff --git a/gdb/solib-dsbt.c b/gdb/solib-dsbt.c
index c6745a9..3585251 100644
--- a/gdb/solib-dsbt.c
+++ b/gdb/solib-dsbt.c
@@ -408,7 +408,7 @@ fetch_loadmap (CORE_ADDR ldmaddr)
}
static void dsbt_relocate_main_executable (void);
-static int enable_break2 (void);
+static int enable_break (void);
/* Scan for DYNTAG in .dynamic section of ABFD. If DYNTAG is found 1 is
returned and the corresponding PTR is set. */
@@ -754,8 +754,6 @@ dsbt_current_sos (void)
sizeof (lm_buf.l_next), byte_order);
}
- enable_break2 ();
-
return sos_head;
}
@@ -795,30 +793,16 @@ cmp_name (asymbol *sym, void *data)
for arranging for the inferior to hit a breakpoint after mapping in
the shared libraries. This function enables that breakpoint.
- On the TIC6X, using the shared library (DSBT), the symbol
- _dl_debug_addr points to the r_debug struct which contains
- a field called r_brk. r_brk is the address of the function
- descriptor upon which a breakpoint must be placed. Being a
- function descriptor, we must extract the entry point in order
- to set the breakpoint.
-
- Our strategy will be to get the .interp section from the
- executable. This section will provide us with the name of the
- interpreter. We'll open the interpreter and then look up
- the address of _dl_debug_addr. We then relocate this address
- using the interpreter's loadmap. Once the relocated address
- is known, we fetch the value (address) corresponding to r_brk
- and then use that value to fetch the entry point of the function
- we're interested in. */
+ On the TIC6X, using the shared library (DSBT), GDB can try to place
+ a breakpoint on '_dl_debug_state' to monitor the shared library
+ event. */
static int
-enable_break2 (void)
+enable_break (void)
{
enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ());
- int success = 0;
- char **bkpt_namep;
asection *interp_sect;
- struct dsbt_info *info = get_dsbt_info ();
+ struct dsbt_info *info;
if (exec_bfd == NULL)
return 0;
@@ -826,6 +810,8 @@ enable_break2 (void)
if (!target_has_execution)
return 0;
+ info = get_dsbt_info ();
+
if (info->enable_break2_done)
return 1;
@@ -846,6 +832,7 @@ enable_break2 (void)
gdb_byte addr_buf[TIC6X_PTR_SIZE];
struct int_elf32_dsbt_loadmap *ldm;
volatile struct gdb_exception ex;
+ int ret;
/* Read the contents of the .interp section into a local buffer;
the contents specify the dynamic linker this program uses. */
@@ -895,81 +882,41 @@ enable_break2 (void)
info->interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect);
}
- addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name, "_dl_debug_addr");
- if (addr == 0)
+ addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name, "_dl_debug_state");
+ if (addr != 0)
{
- warning (_("Could not find symbol _dl_debug_addr in dynamic linker"));
- enable_break_failure_warning ();
- gdb_bfd_unref (tmp_bfd);
- return 0;
- }
-
- if (solib_dsbt_debug)
- fprintf_unfiltered (gdb_stdlog,
- "enable_break: _dl_debug_addr (prior to relocation) = %s\n",
- hex_string_custom (addr, 8));
+ if (solib_dsbt_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "enable_break: _dl_debug_state (prior to relocation) = %s\n",
+ hex_string_custom (addr, 8));
+ addr += displacement_from_map (ldm, addr);
- addr += displacement_from_map (ldm, addr);
+ if (solib_dsbt_debug)
+ fprintf_unfiltered (gdb_stdlog,
+ "enable_break: _dl_debug_state (after relocation) = %s\n",
+ hex_string_custom (addr, 8));
- if (solib_dsbt_debug)
- fprintf_unfiltered (gdb_stdlog,
- "enable_break: _dl_debug_addr (after relocation) = %s\n",
- hex_string_custom (addr, 8));
+ /* Now (finally!) create the solib breakpoint. */
+ create_solib_event_breakpoint (target_gdbarch (), addr);
- /* Fetch the address of the r_debug struct. */
- if (target_read_memory (addr, addr_buf, sizeof addr_buf) != 0)
- {
- warning (_("Unable to fetch contents of _dl_debug_addr "
- "(at address %s) from dynamic linker"),
- hex_string_custom (addr, 8));
+ info->enable_break2_done = 1;
+ ret = 1;
}
- addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order);
-
- if (solib_dsbt_debug)
- fprintf_unfiltered (gdb_stdlog,
- "enable_break: _dl_debug_addr[0..3] = %s\n",
- hex_string_custom (addr, 8));
-
- /* If it's zero, then the ldso hasn't initialized yet, and so
- there are no shared libs yet loaded. */
- if (addr == 0)
+ else
{
if (solib_dsbt_debug)
fprintf_unfiltered (gdb_stdlog,
- "enable_break: ldso not yet initialized\n");
- /* Do not warn, but mark to run again. */
- return 0;
+ "enable_break: _dl_debug_state is not found\n");
+ ret = 0;
}
- /* Fetch the r_brk field. It's 8 bytes from the start of
- _dl_debug_addr. */
- if (target_read_memory (addr + 8, addr_buf, sizeof addr_buf) != 0)
- {
- warning (_("Unable to fetch _dl_debug_addr->r_brk "
- "(at address %s) from dynamic linker"),
- hex_string_custom (addr + 8, 8));
- enable_break_failure_warning ();
- gdb_bfd_unref (tmp_bfd);
- return 0;
- }
- addr = extract_unsigned_integer (addr_buf, sizeof addr_buf, byte_order);
-
/* We're done with the temporary bfd. */
gdb_bfd_unref (tmp_bfd);
/* We're also done with the loadmap. */
xfree (ldm);
- /* Remove all the solib event breakpoints. Their addresses
- may have changed since the last time we ran the program. */
- remove_solib_event_breakpoints ();
-
- /* Now (finally!) create the solib breakpoint. */
- create_solib_event_breakpoint (target_gdbarch (), addr);
-
- info->enable_break2_done = 1;
-
- return 1;
+ return ret;
}
/* Tell the user we couldn't set a dynamic linker breakpoint. */
@@ -979,44 +926,6 @@ enable_break2 (void)
return 0;
}
-static int
-enable_break (void)
-{
- asection *interp_sect;
- struct minimal_symbol *start;
-
- /* Check for the presence of a .interp section. If there is no
- such section, the executable is statically linked. */
-
- interp_sect = bfd_get_section_by_name (exec_bfd, ".interp");
-
- if (interp_sect == NULL)
- {
- if (solib_dsbt_debug)
- fprintf_unfiltered (gdb_stdlog,
- "enable_break: No .interp section found.\n");
- return 0;
- }
-
- start = lookup_minimal_symbol ("_start", NULL, symfile_objfile);
- if (start == NULL)
- {
- if (solib_dsbt_debug)
- fprintf_unfiltered (gdb_stdlog,
- "enable_break: symbol _start is not found.\n");
- return 0;
- }
-
- create_solib_event_breakpoint (target_gdbarch (),
- SYMBOL_VALUE_ADDRESS (start));
-
- if (solib_dsbt_debug)
- fprintf_unfiltered (gdb_stdlog,
- "enable_break: solib event breakpoint placed at : %s\n",
- hex_string_custom (SYMBOL_VALUE_ADDRESS (start), 8));
- return 1;
-}
-
/* Once the symbols from a shared object have been loaded in the usual
way, we are called to do any system specific symbol handling that
is needed. */