fix local vs global symbol names, locals now are local

1 files changed, 60 insertions, 5 deletions

diff --git a/mld/symtab.c b/mld/symtab.c
index eca6dbe..5abad2a 100644
--- a/mld/symtab.c
+++ b/mld/symtab.c
@@ -1,5 +1,6 @@
 #include <elf.h>
 #include <merror.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <melf.h>
 
@@ -19,6 +20,7 @@ int symtab_init(struct symbol_table *symtab)
 	}
 
 	symtab->syms[0] = (Elf32_Sym){0};
+	symtab->map = NULL;
 
 	return M_SUCCESS;
 }
@@ -45,16 +47,69 @@ int symtab_push(struct symbol_table *symtab, const Elf32_Sym *sym)
 	return M_SUCCESS;
 }
 
-int symtab_get(struct symbol_table *symtab, Elf32_Sym **res, const char *name)
+int symtab_get(struct symbol_table *symtab, Elf32_Sym **res, const char *name,
+	       int32_t obj_idx)
 {
 	for (size_t i = 0; i < symtab->len; i++) {
 		Elf32_Sym *sym = &symtab->syms[i];
 		const char *symname = symtab->strtab->data + B32(sym->st_name);
-		if (strcmp(name, symname) == 0) {
-			if (res != NULL)
-				*res = sym;
-			return M_SUCCESS;
+		if (strcmp(name, symname) != 0)
+			continue;
+
+		// only allow retrevial of local variables from the
+		// same object
+		if (sym->st_info >> 4 != STB_GLOBAL && symtab->map != NULL &&
+			obj_idx >= 0) {
+			struct object *obj = symtab->map->meta[i];
+			if (obj->index != (uint32_t)obj_idx)
+				continue;
+		} else if (obj_idx < 0 && sym->st_info >> 4 != STB_GLOBAL) {
+			// when obj_idx is -1, we only want to reutrn
+			// global symbols
+			continue;
 		}
+
+		if (res != NULL)
+			*res = sym;
+		return M_SUCCESS;
 	}
 	return M_ERROR;
 }
+
+int symtab_map_push(struct symbol_table_mapping *symtabm, struct object *meta)
+{
+	if (symtabm->len >= symtabm->size) {
+		uint32_t size = symtabm->size * 2;
+		void *new = realloc(symtabm->meta,
+		      sizeof(struct object *) * size);
+		if (new == NULL) {
+			PERROR("cannot realloc");
+			return M_ERROR;
+		}
+		symtabm->size = size;
+		symtabm->meta = new;
+	}
+
+	symtabm->meta[symtabm->len++] = meta;
+	return M_SUCCESS;
+}
+
+int symtab_map_init(struct symbol_table_mapping *symtabm)
+{
+	symtabm->len = 0;
+	symtabm->size = SYMTAB_INIT_LEN;
+	symtabm->meta = malloc(sizeof(struct object *) * symtabm->size);
+
+	if (symtabm->meta == NULL) {
+		PERROR("cannot alloc");
+		return M_ERROR;
+	}
+
+	return M_SUCCESS;
+}
+
+
+void symtab_map_free(struct symbol_table_mapping *symtabm)
+{
+	free(symtabm->meta);
+}