[PATCH dwarves v2 1/4] dutil: return ELF section name when looked up by index

Stephen Brennan <[email protected]> Fri, 20 Sep 2024 01:18:58 -0700
Newsgroups org.kernel.vger.linux-debuggers,org.kernel.vger.bpf,org.kernel.vger.dwarves
Message-ID <[email protected]>
Signed-off-by: Stephen Brennan <[email protected]>
Reviewed-by: Alan Maguire <[email protected]>
---
 dutil.c | 14 +++++++++++---
 dutil.h |  2 +-
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/dutil.c b/dutil.c
index 97c4474..14f1340 100644
--- a/dutil.c
+++ b/dutil.c
@@ -207,13 +207,21 @@ Elf_Scn *elf_section_by_name(Elf *elf, GElf_Shdr *shp, const char *name, size_t
 	return sec;
 }
 
-Elf_Scn *elf_section_by_idx(Elf *elf, GElf_Shdr *shp, int idx)
+Elf_Scn *elf_section_by_idx(Elf *elf, GElf_Shdr *shp, int idx, const char **name_out)
 {
 	Elf_Scn *sec;
+	size_t str_idx;
 
 	sec = elf_getscn(elf, idx);
-	if (sec)
-		gelf_getshdr(sec, shp);
+	if (!sec)
+		return NULL;
+	if (!gelf_getshdr(sec, shp))
+		return NULL;
+	if (name_out) {
+		if (elf_getshdrstrndx(elf, &str_idx))
+			return NULL;
+		*name_out = elf_strptr(elf, str_idx, shp->sh_name);
+	}
 	return sec;
 }
 
diff --git a/dutil.h b/dutil.h
index 335a17c..ff78aa6 100644
--- a/dutil.h
+++ b/dutil.h
@@ -328,7 +328,7 @@ void *zalloc(const size_t size);
 
 Elf_Scn *elf_section_by_name(Elf *elf, GElf_Shdr *shp, const char *name, size_t *index);
 
-Elf_Scn *elf_section_by_idx(Elf *elf, GElf_Shdr *shp, int idx);
+Elf_Scn *elf_section_by_idx(Elf *elf, GElf_Shdr *shp, int idx, const char **name_out);
 
 #ifndef SHT_GNU_ATTRIBUTES
 /* Just a way to check if we're using an old elfutils version */
-- 
2.43.5