Return more than one ELF symbol.

As the code now handles more than one global ELF symbol, this commit updates the find-by-name routine to return all ELF symbols (locals and globals) with the same name.
In the case none starting address is specified, the search is performed in all opened symbol files of the context to gather all symbols with the same name. It is up to the caller to look through the returned list to get the symbol that fits its needs.

1 files changed, 51 insertions, 24 deletions

diff --git a/agent/tcf/services/symbols_elf.c b/agent/tcf/services/symbols_elf.c
index 28461c27..140db6ef 100644
--- a/agent/tcf/services/symbols_elf.c
+++ b/agent/tcf/services/symbols_elf.c
@@ -495,16 +495,33 @@ static int check_in_range(ObjectInfo * obj, ContextAddress rt_offs, ContextAddre
     return 0;
 }
 
-static void add_to_find_symbol_buf(ObjectInfo * obj) {
-    unsigned n = 0;
-    while (n < find_symbol_cnt) {
-        if (find_symbol_buf[n++]->obj == obj) return;
+static Symbol * add_to_find_symbol_buf(ObjectInfo * obj, Symbol * sym) {
+    assert (obj != NULL || sym != NULL);
+
+    if (obj != NULL) {
+        unsigned n = 0;
+        while (n < find_symbol_cnt) {
+            if (find_symbol_buf[n++]->obj == obj) return find_symbol_buf[n - 1];
+        }
+    }
+    else if (sym->tbl != NULL){
+        unsigned n = 0;
+        while (n < find_symbol_cnt) {
+            if (find_symbol_buf[n]->tbl == sym->tbl && find_symbol_buf[n]->index == sym->index) return find_symbol_buf[n];
+            n++;
+        }
     }
     if (find_symbol_cnt >= find_symbol_max) {
         find_symbol_max += 32;
         find_symbol_buf = (Symbol **)loc_realloc(find_symbol_buf, sizeof(Symbol *) * find_symbol_max);
     }
-    object2symbol(obj, find_symbol_buf + find_symbol_cnt++);
+    if (obj != NULL) {
+        object2symbol(obj, find_symbol_buf + find_symbol_cnt++);
+    }
+    else {
+        find_symbol_buf[find_symbol_cnt++] = sym;
+    }
+    return find_symbol_buf[find_symbol_cnt - 1];
 }
 
 static int find_by_name_in_pub_names(DWARFCache * cache, const char * name, Symbol ** sym) {
@@ -518,7 +535,7 @@ static int find_by_name_in_pub_names(DWARFCache * cache, const char * name, Symb
             ObjectInfo * obj = tbl->mNext[n].mObject;
             if (obj->mFlags & DOIF_external) {
                 if (cmp_symbol_names(obj->mName, name) == 0) {
-                    object2symbol(obj, sym);
+                    *sym = add_to_find_symbol_buf (obj, NULL);
                     return 1;
                 }
             }
@@ -541,15 +558,15 @@ static int find_by_name_in_pub_names(DWARFCache * cache, const char * name, Symb
             n = tbl->mNext[n].mNext;
         }
         if (other != NULL) {
-            object2symbol(other, sym);
+            *sym = add_to_find_symbol_buf (other, NULL);
             return 1;
         }
         if (type != NULL) {
-            object2symbol(type, sym);
+            *sym = add_to_find_symbol_buf (type, NULL);
             return 1;
         }
         if (decl != NULL) {
-            object2symbol(decl, sym);
+            *sym = add_to_find_symbol_buf (decl, NULL);
             return 1;
         }
     }
@@ -572,7 +589,9 @@ static ObjectInfo * find_definition(ObjectInfo * decl) {
         int found = 0;
         Symbol * sym = NULL;
         DWARFCache * cache = get_dwarf_cache(get_dwarf_file(decl->mCompUnit->mFile));
+        int find_symbol_cnt_sav = find_symbol_cnt;
         found = find_by_name_in_pub_names(cache, decl->mName, &sym);
+        find_symbol_cnt = find_symbol_cnt_sav;
         if (found && sym->obj != NULL &&
             sym->obj->mTag == decl->mTag &&
             (sym->obj->mFlags & DOIF_declaration) == 0) return sym->obj;
@@ -615,7 +634,7 @@ static void find_in_object_tree(ObjectInfo * parent, ContextAddress rt_offs, Con
     obj = children;
     while (obj != NULL) {
         if ((obj->mFlags & DOIF_specification) == 0 && obj->mName != NULL && cmp_symbol_names(obj->mName, name) == 0) {
-            add_to_find_symbol_buf(find_definition(obj));
+            add_to_find_symbol_buf(find_definition(obj), NULL);
         }
         if (parent->mTag == TAG_subprogram && ip != 0) {
             if (!obj_ptr_chk) {
@@ -673,7 +692,7 @@ static void find_in_object_tree(ObjectInfo * parent, ContextAddress rt_offs, Con
                 decl = find_object(get_dwarf_cache(obj->mCompUnit->mFile), (ContextAddress)p.mValue);
                 if (decl != NULL) {
                     if (obj->mName != NULL || (decl->mName != NULL && cmp_symbol_names(decl->mName, name) == 0)) {
-                        add_to_find_symbol_buf(find_definition(decl));
+                        add_to_find_symbol_buf(find_definition(decl), NULL);
                     }
                 }
             }
@@ -723,8 +742,8 @@ static int find_in_dwarf(const char * name, Symbol ** sym) {
 static int find_by_name_in_sym_table(ELF_File * file, const char * name, int globals, Symbol ** res) {
     unsigned m = 0;
     unsigned h = calc_symbol_name_hash(name);
-    unsigned cnt = 0;
     Context * prs = context_get_group(sym_ctx, CONTEXT_GROUP_SYMBOLS);
+    int found = 0;
     for (m = 1; m < file->section_cnt; m++) {
         unsigned n;
         ELF_Section * tbl = file->sections + m;
@@ -734,8 +753,8 @@ static int find_by_name_in_sym_table(ELF_File * file, const char * name, int glo
             ELF_SymbolInfo sym_info;
             unpack_elf_symbol_info(tbl, n, &sym_info);
             if (cmp_symbol_names(name, sym_info.name) == 0 && (!globals || sym_info.bind == STB_GLOBAL || sym_info.bind == STB_WEAK)) {
-                int found = 0;
                 ContextAddress addr = 0;
+                int found_dwarf = 0;
                 if (sym_info.section_index != SHN_ABS && syminfo2address(prs, &sym_info, &addr) == 0) {
                     UnitAddressRange * range = elf_find_unit(sym_ctx, addr, addr, NULL);
                     if (range != NULL) {
@@ -749,9 +768,8 @@ static int find_by_name_in_sym_table(ELF_File * file, const char * name, int glo
                                 case TAG_subprogram:
                                 case TAG_variable:
                                     if (cmp_symbol_names(obj->mName, name) == 0) {
-                                        object2symbol(obj, res);
-                                        found = 1;
-                                        cnt++;
+                                        *res = add_to_find_symbol_buf (obj, NULL);
+                                        found_dwarf = 1;
                                     }
                                     break;
                                 }
@@ -760,7 +778,7 @@ static int find_by_name_in_sym_table(ELF_File * file, const char * name, int glo
                         }
                     }
                 }
-                if (!found) {
+                if (!found_dwarf) {
                     Symbol * sym = alloc_symbol();
                     sym->frame = STACK_NO_FRAME;
                     sym->ctx = prs;
@@ -785,14 +803,14 @@ static int find_by_name_in_sym_table(ELF_File * file, const char * name, int glo
                         sym->sym_class = SYM_CLASS_VALUE;
                         break;
                     }
-                    *res = sym;
-                    cnt++;
+                    *res = add_to_find_symbol_buf (NULL, sym);
                 }
+                found = 1;
             }
             n = tbl->sym_names_next[n];
         }
     }
-    return cnt == 1;
+    return found;
 }
 
 int find_symbol_by_name(Context * ctx, int frame, ContextAddress ip, const char * name, Symbol ** res) {
@@ -866,7 +884,10 @@ int find_symbol_by_name(Context * ctx, int frame, ContextAddress ip, const char
                     error = trap.error;
                     break;
                 }
-                if (found) break;
+                if (found) {
+                    *res = find_symbol_buf[find_symbol_pos++];
+                    break;
+                }
                 file = elf_list_next(sym_ctx);
                 if (file == NULL) error = errno;
             }
@@ -951,26 +972,31 @@ int find_symbol_by_name(Context * ctx, int frame, ContextAddress ip, const char
         /* Search in pub names of all other files */
         ELF_File * file = elf_list_first(sym_ctx, 0, ~(ContextAddress)0);
         if (file == NULL) error = errno;
+
         while (error == 0 && file != NULL) {
             if (file != curr_file) {
+                int found_pub, found_symtbl = 0;
                 Trap trap;
                 if (set_trap(&trap)) {
                     DWARFCache * cache = get_dwarf_cache(get_dwarf_file(file));
-                    found = find_by_name_in_pub_names(cache, name, res);
-                    if (!found) found = find_by_name_in_sym_table(file, name, sym_ip != 0, res);
+                    found_pub = find_by_name_in_pub_names(cache, name, res);
+                    if (sym_ip == 0 || !found_pub)
+                        found_symtbl = find_by_name_in_sym_table(file, name, sym_ip != 0, res);
                     clear_trap(&trap);
                 }
                 else {
                     error = trap.error;
                     break;
                 }
-                if (found) break;
+                found = found || found_pub || found_symtbl;
+                if (sym_ip != 0 && found) break;
             }
             file = elf_list_next(sym_ctx);
             if (file == NULL) error = errno;
         }
         elf_list_done(sym_ctx);
         sym_ip = 0;
+        if (found) *res = find_symbol_buf[find_symbol_pos++];
     }
 
     if (error == 0 && !found) error = ERR_SYM_NOT_FOUND;
@@ -1010,6 +1036,7 @@ int find_symbol_in_scope(Context * ctx, int frame, ContextAddress ip, Symbol * s
                 }
                 if (!found) {
                     found = find_by_name_in_sym_table(file, name, 0, res);
+                    if (found) *res = find_symbol_buf[find_symbol_pos++];
                 }
                 clear_trap(&trap);
             }