[RFC PATCH 4/9] dwarf_loader: introduce pre_load_module hook to conf_load

[Ihor Solodrai <ihor.solodrai@xxxxx>]

Add a function pointer to conf_load, which is called immediately after
Elf is extracted from Dwfl_Module in cus__proces_dwflmod.

This is a preparation for making elf_functions table shared between
encoders. Shared table can be built as soon as the relevant Elf is
available.

Signed-off-by: Ihor Solodrai <ihor.solodrai@xxxxx>
---
 dwarf_loader.c | 14 +++++++-------
 dwarves.h      | 11 +++++++++--
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/dwarf_loader.c b/dwarf_loader.c
index 598fde4..5d55649 100644
--- a/dwarf_loader.c
+++ b/dwarf_loader.c
@@ -3796,13 +3796,6 @@ static int cus__load_module(struct cus *cus, struct conf_load *conf,
 	return DWARF_CB_OK;
 }
 
-struct process_dwflmod_parms {
-	struct cus	 *cus;
-	struct conf_load *conf;
-	const char	 *filename;
-	uint32_t	 nr_dwarf_sections_found;
-};
-
 static int cus__process_dwflmod(Dwfl_Module *dwflmod,
 				void **userdata __maybe_unused,
 				const char *name __maybe_unused,
@@ -3826,11 +3819,18 @@ static int cus__process_dwflmod(Dwfl_Module *dwflmod,
 	Dwarf *dw = dwfl_module_getdwarf(dwflmod, &dwbias);
 
 	int err = DWARF_CB_OK;
+	if (parms->conf->pre_load_module) {
+		err = parms->conf->pre_load_module(dwflmod, elf);
+		if (err)
+			return DWARF_CB_ABORT;
+	}
+
 	if (dw != NULL) {
 		++parms->nr_dwarf_sections_found;
 		err = cus__load_module(cus, parms->conf, dwflmod, dw, elf,
 				       parms->filename);
 	}
+
 	/*
 	 * XXX We will fall back to try finding other debugging
 	 * formats (CTF), so no point in telling this to the user
diff --git a/dwarves.h b/dwarves.h
index 1cb0d62..1a0bd4b 100644
--- a/dwarves.h
+++ b/dwarves.h
@@ -37,6 +37,7 @@
 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
 
 struct cu;
+struct cus;
 
 enum load_steal_kind {
 	LSK__KEEPIT,
@@ -59,6 +60,13 @@ typedef uint32_t type_id_t;
 struct btf;
 struct conf_fprintf;
 
+struct process_dwflmod_parms {
+	struct cus	 *cus;
+	struct conf_load *conf;
+	const char	 *filename;
+	uint32_t	 nr_dwarf_sections_found;
+};
+
 /** struct conf_load - load configuration
  * @thread_exit - called at the end of a thread, 1st user: BTF encoder dedup
  * @extra_dbg_info - keep original debugging format extra info
@@ -107,6 +115,7 @@ struct conf_load {
 	struct conf_fprintf	*conf_fprintf;
 	int			(*threads_prepare)(struct conf_load *conf, int nr_threads, void **thr_data);
 	int			(*threads_collect)(struct conf_load *conf, int nr_threads, void **thr_data, int error);
+	int			(*pre_load_module)(Dwfl_Module *mod, Elf *elf);
 };
 
 /** struct conf_fprintf - hints to the __fprintf routines
@@ -168,8 +177,6 @@ struct conf_fprintf {
 	uint8_t    skip_emitting_modifier:1;
 };
 
-struct cus;
-
 struct cus *cus__new(void);
 void cus__delete(struct cus *cus);
 
-- 
2.47.0