[RFC PATCH v2 14/37] tools lib bpf: collect symbol table in object files.

[Wang Nan <wangnan0@huawei.com>]

This patch collects symbols section. This section is useful when
linking ELF maps.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
---
 tools/lib/bpf/libbpf.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 43b22a5..2068f0b 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -94,6 +94,7 @@ struct bpf_object {
 		int fd;
 		Elf *elf;
 		GElf_Ehdr ehdr;
+		Elf_Data *symbols;
 	} elf;
 };
 #define obj_elf_valid(o)	((o)->elf.fd >= 0)
@@ -142,6 +143,8 @@ static void bpf_obj_clear_elf(struct bpf_object *obj)
 		elf_end(obj->elf.elf);
 		obj->elf.elf = NULL;
 	}
+	obj->elf.symbols = NULL;
+
 	if (obj->elf.fd >= 0) {
 		close(obj->elf.fd);
 		obj->elf.fd = -1;
@@ -370,6 +373,14 @@ static int bpf_obj_elf_collect(struct bpf_object *obj)
 		else if (strcmp(name, "config") == 0)
 			err = bpf_obj_config_init(obj, data->d_buf,
 						  data->d_size);
+		else if (sh.sh_type == SHT_SYMTAB) {
+			if (obj->elf.symbols) {
+				pr_warning("bpf: multiple SYMTAB in %s\n",
+					   obj->path);
+				err = -EEXIST;
+			} else
+				obj->elf.symbols = data;
+		}
 		if (err)
 			goto out;
 	}
-- 
1.8.3.4