Am 30.11.2023 um 20:53 schrieb Ian Lance Taylor:
On Fri, Jan 20, 2023 at 2:55 AM Björn Schäpers <g...@hazardy.de> wrote:
From: Björn Schäpers <bjo...@hazardy.de>
Fixes https://github.com/ianlancetaylor/libbacktrace/issues/53, except
that libraries loaded after the backtrace_initialize are not handled.
But as far as I can see that's the same for elf.
Thanks, but I don't want a patch that loops using goto statements.
Please rewrite to avoid that. It may be simpler to call a function.
Also starting with a module count of 1000 seems like a lot. Do
typical Windows programs load that many modules?
Ian
Rewritten using a function.
If that is commited, could you attribute that commit to me (--author="Björn
Schäpers <bjo...@hazardy.de>")?
Thanks and kind regards,
Björn.
From bd552716ee7937cad9d54d4966532d6ea6dbc1bc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Sch=C3=A4pers?= <bjo...@hazardy.de>
Date: Sun, 30 Apr 2023 23:54:32 +0200
Subject: [PATCH] libbacktrace: get debug information for loaded dlls
MIME-Version: 1.0
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Fixes https://github.com/ianlancetaylor/libbacktrace/issues/53, except
that libraries loaded after the backtrace_initialize are not handled.
But as far as I can see that's the same for elf.
Tested on x86_64-linux and i686-w64-mingw32.
-- >8 --
* pecoff.c (coff_add): New argument for the module handle of the
file, to get the base address.
* pecoff.c (backtrace_initialize): Iterate over loaded libraries
and call coff_add.
Signed-off-by: Björn Schäpers <bjo...@hazardy.de>
---
libbacktrace/pecoff.c | 104 ++++++++++++++++++++++++++++++++++++++----
1 file changed, 96 insertions(+), 8 deletions(-)
diff --git a/libbacktrace/pecoff.c b/libbacktrace/pecoff.c
index f976a963bf3..3eb9c4a4853 100644
--- a/libbacktrace/pecoff.c
+++ b/libbacktrace/pecoff.c
@@ -49,6 +49,7 @@ POSSIBILITY OF SUCH DAMAGE. */
#endif
#include <windows.h>
+#include <psapi.h>
#endif
/* Coff file header. */
@@ -592,7 +593,8 @@ coff_syminfo (struct backtrace_state *state, uintptr_t addr,
static int
coff_add (struct backtrace_state *state, int descriptor,
backtrace_error_callback error_callback, void *data,
- fileline *fileline_fn, int *found_sym, int *found_dwarf)
+ fileline *fileline_fn, int *found_sym, int *found_dwarf,
+ uintptr_t module_handle ATTRIBUTE_UNUSED)
{
struct backtrace_view fhdr_view;
off_t fhdr_off;
@@ -870,12 +872,7 @@ coff_add (struct backtrace_state *state, int descriptor,
}
#ifdef HAVE_WINDOWS_H
- {
- uintptr_t module_handle;
-
- module_handle = (uintptr_t) GetModuleHandle (NULL);
- base_address = module_handle - image_base;
- }
+ base_address = module_handle - image_base;
#endif
if (!backtrace_dwarf_add (state, base_address, &dwarf_sections,
@@ -903,6 +900,53 @@ coff_add (struct backtrace_state *state, int descriptor,
return 0;
}
+#ifdef HAVE_WINDOWS_H
+static void
+free_modules (struct backtrace_state *state,
+ backtrace_error_callback error_callback, void *data,
+ HMODULE **modules, DWORD bytes_allocated)
+{
+ backtrace_free (state, *modules, bytes_allocated, error_callback, data);
+ *modules = NULL;
+}
+
+static void
+get_all_modules (struct backtrace_state *state,
+ backtrace_error_callback error_callback, void *data,
+ HMODULE **modules, DWORD *module_count, DWORD *bytes_allocated)
+{
+ DWORD bytes_needed = 0;
+
+ for (;;)
+ {
+ *bytes_allocated = *module_count * sizeof(HMODULE);
+ *modules = backtrace_alloc (state, *bytes_allocated, error_callback,
data);
+
+ if (*modules == NULL)
+ return;
+
+ if (!EnumProcessModules (GetCurrentProcess (), *modules, *module_count,
+ &bytes_needed))
+ {
+ error_callback(data, "Could not enumerate process modules",
+ (int) GetLastError ());
+ free_modules (state, error_callback, data, modules, *bytes_allocated);
+ return;
+ }
+
+ *module_count = bytes_needed / sizeof(HMODULE);
+ if (bytes_needed <= *bytes_allocated)
+ {
+ return;
+ }
+
+ free_modules (state, error_callback, data, modules, *bytes_allocated);
+ // Add an extra of 2, of some module is loaded in another thread.
+ *module_count += 2;
+ }
+}
+#endif
+
/* Initialize the backtrace data we need from an ELF executable. At
the ELF level, all we need to do is find the debug info
sections. */
@@ -917,12 +961,56 @@ backtrace_initialize (struct backtrace_state *state,
int found_sym;
int found_dwarf;
fileline coff_fileline_fn;
+ uintptr_t module_handle = 0;
+
+#ifdef HAVE_WINDOWS_H
+ DWORD i;
+ DWORD module_count = 100;
+ DWORD bytes_allocated_for_modules = 0;
+ HMODULE *modules = NULL;
+ char module_name[MAX_PATH];
+ int module_found_sym;
+ fileline module_fileline_fn;
+
+ module_handle = (uintptr_t) GetModuleHandle (NULL);
+#endif
ret = coff_add (state, descriptor, error_callback, data,
- &coff_fileline_fn, &found_sym, &found_dwarf);
+ &coff_fileline_fn, &found_sym, &found_dwarf, module_handle);
if (!ret)
return 0;
+#ifdef HAVE_WINDOWS_H
+ get_all_modules (state, error_callback, data, &modules,
+ &module_count, &bytes_allocated_for_modules);
+
+ for (i = 0; i < module_count; ++i)
+ {
+ if (GetModuleFileNameA (modules[i], module_name, MAX_PATH - 1))
+ {
+ if (strcmp (filename, module_name) == 0)
+ continue;
+
+ module_handle = (uintptr_t) GetModuleHandleA (module_name);
+ if (module_handle == 0)
+ continue;
+
+ descriptor = backtrace_open (module_name, error_callback, data, NULL);
+ if (descriptor < 0)
+ continue;
+
+ coff_add (state, descriptor, error_callback, data,
+ &module_fileline_fn, &module_found_sym, &found_dwarf,
+ module_handle);
+ if (module_found_sym)
+ found_sym = 1;
+ }
+ }
+
+ if (modules)
+ free_modules (state, error_callback, data, &modules,
bytes_allocated_for_modules);
+#endif
+
if (!state->threaded)
{
if (found_sym)
--
2.42.1
