From 944c4003bd8a0be89c96f23b1401cd74e074fec6 Mon Sep 17 00:00:00 2001
From: Jan Boon <jan.boon@kaetemi.be>
Date: Mon, 16 Sep 2019 15:24:16 +0800
Subject: [PATCH] Add function to list all symbols, for purpose of linking
 separate in-memory compilations

---
 libtcc.h |  4 ++++
 tcc.h    |  2 ++
 tccelf.c | 31 +++++++++++++++++++++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/libtcc.h b/libtcc.h
index a1b31e30..0c6bb3d6 100644
--- a/libtcc.h
+++ b/libtcc.h
@@ -93,6 +93,10 @@ LIBTCCAPI int tcc_relocate(TCCState *s1, void *ptr);
 /* return symbol value or NULL if not found */
 LIBTCCAPI void *tcc_get_symbol(TCCState *s, const char *name);
 
+/* return symbol value or NULL if not found */
+LIBTCCAPI void tcc_list_symbols(TCCState *s, void *ctx,
+    void (*symbol_cb)(void *ctx, const char *name, const void *val));
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/tcc.h b/tcc.h
index 7f01afac..c48b45bf 100644
--- a/tcc.h
+++ b/tcc.h
@@ -1470,6 +1470,8 @@ ST_FUNC struct sym_attr *get_sym_attr(TCCState *s1, int index, int alloc);
 ST_FUNC void squeeze_multi_relocs(Section *sec, size_t oldrelocoffset);
 
 ST_FUNC addr_t get_elf_sym_addr(TCCState *s, const char *name, int err);
+ST_FUNC void list_elf_symbols(TCCState *s, void *ctx,
+    void (*symbol_cb)(void *ctx, const char *name, const void *val));
 #if defined TCC_IS_NATIVE || defined TCC_TARGET_PE
 ST_FUNC void *tcc_get_symbol_err(TCCState *s, const char *name);
 #endif
diff --git a/tccelf.c b/tccelf.c
index 5b6737e7..707ce22d 100644
--- a/tccelf.c
+++ b/tccelf.c
@@ -471,12 +471,43 @@ ST_FUNC addr_t get_elf_sym_addr(TCCState *s, const char *name, int err)
     return sym->st_value;
 }
 
+/* list elf symbol names and values */
+ST_FUNC void list_elf_symbols(TCCState *s, void *ctx,
+    void (*symbol_cb)(void *ctx, const char *name, const void *val))
+{
+    ElfW(Sym) *sym;
+    Section *symtab;
+    int sym_index, end_sym;
+    const char *name;
+    unsigned char sym_vis, sym_bind;
+
+    symtab = s->symtab;
+    end_sym = symtab->data_offset / sizeof (ElfSym);
+    for (sym_index = 0; sym_index < end_sym; ++sym_index) {
+        sym = &((ElfW(Sym) *)symtab->data)[sym_index];
+        if (sym->st_value) {
+            name = (char *) symtab->link->data + sym->st_name;
+            sym_bind = ELFW(ST_BIND)(sym->st_info);
+            sym_vis = ELFW(ST_VISIBILITY)(sym->st_other);
+            if (sym_bind == STB_GLOBAL && sym_vis == STV_DEFAULT)
+                symbol_cb(ctx, name, (void*)(uintptr_t)sym->st_value);
+        }
+    }
+}
+
 /* return elf symbol value */
 LIBTCCAPI void *tcc_get_symbol(TCCState *s, const char *name)
 {
     return (void*)(uintptr_t)get_elf_sym_addr(s, name, 0);
 }
 
+/* list elf symbol names and values */
+LIBTCCAPI void tcc_list_symbols(TCCState *s, void *ctx,
+    void (*symbol_cb)(void *ctx, const char *name, const void *val))
+{
+    list_elf_symbols(s, ctx, symbol_cb);
+}
+
 #if defined TCC_IS_NATIVE || defined TCC_TARGET_PE
 /* return elf symbol value or error */
 ST_FUNC void* tcc_get_symbol_err(TCCState *s, const char *name)