release loaded dlls cleanly (Sam K)

tcc.c

@@ -222,6 +222,7 @@ typedef struct Section {
 
 typedef struct DLLReference {
     int level;
+    void *handle;
     char name[1];
 } DLLReference;
 
@@ -9486,8 +9487,6 @@ static void preprocess_init(TCCState *s1)
     vtop = vstack - 1;
     s1->pack_stack[0] = 0;
     s1->pack_stack_ptr = s1->pack_stack;
-
-    macro_ptr = NULL;
 }
 
 /* compile the C file opened in 'file'. Return non zero if errors. */
@@ -10095,6 +10094,8 @@ static void tcc_cleanup(void)
     cstr_free(&tokcstr);
     /* reset symbol stack */
     sym_free_first = NULL;
+    /* cleanup from error/setjmp */
+    macro_ptr = NULL;
 }
 
 TCCState *tcc_new(void)
@@ -10227,6 +10228,14 @@ void tcc_delete(TCCState *s1)
     for(i = 1; i < s1->nb_sections; i++)
         free_section(s1->sections[i]);
     tcc_free(s1->sections);
+	
+    /* free any loaded DLLs */
+    for ( i = 0; i < s1->nb_loaded_dlls; i++)
+    {
+        DLLReference *ref = s1->loaded_dlls[i];
+        if ( ref->handle )
+            dlclose(ref->handle);
+    }
     
     /* free loaded dlls array */
     dynarray_reset(&s1->loaded_dlls, &s1->nb_loaded_dlls);

tccelf.c

@@ -2276,7 +2276,7 @@ static int tcc_load_dll(TCCState *s1, int fd, const char *filename, int level)
     //    printf("loading dll '%s'\n", soname);
 
     /* add the dll and its level */
-    dllref = tcc_malloc(sizeof(DLLReference) + strlen(soname));
+    dllref = tcc_mallocz(sizeof(DLLReference) + strlen(soname));
     dllref->level = level;
     strcpy(dllref->name, soname);
     dynarray_add((void ***)&s1->loaded_dlls, &s1->nb_loaded_dlls, dllref);

tccpe.c

@@ -465,6 +465,8 @@ ST_FN int pe_find_import(TCCState * s1, const char *symbol)
 # include <dlfcn.h>
 # define LoadLibrary(s) dlopen(s, RTLD_NOW)
 # define GetProcAddress(h,s) dlsym(h, s)
+#else
+# define dlclose(h) FreeLibrary(h)
 #endif
 
 /* for the -run option: dynamically load symbol from dll */
@@ -472,16 +474,21 @@ void *resolve_sym(struct TCCState *s1, const char *symbol, int type)
 {
     char buffer[100];
     int sym_index, dll_index;
-    void *hModule, *addr, **m;
+    void *addr, **m;
+    DLLReference *dllref;
 
     sym_index = pe_find_import(s1, symbol);
     if (0 == sym_index)
         return NULL;
     dll_index = ((Elf32_Sym *)s1->dynsymtab_section->data + sym_index)->st_value;
-    hModule = LoadLibrary(s1->loaded_dlls[dll_index-1]->name);
-    addr = GetProcAddress(hModule, symbol);
+    dllref = s1->loaded_dlls[dll_index-1];
+    if ( !dllref->handle )
+    {
+        dllref->handle = LoadLibrary(dllref->name);
+    }
+    addr = GetProcAddress(dllref->handle, symbol);
     if (NULL == addr)
-        addr = GetProcAddress(hModule, get_alt_symbol(buffer, symbol));
+        addr = GetProcAddress(dllref->handle, get_alt_symbol(buffer, symbol));
 
     if (addr && STT_OBJECT == type) {
         /* need to return a pointer to the address for data objects */
@@ -1413,9 +1420,8 @@ PUB_FN int pe_load_def_file(TCCState *s1, int fd)
             continue;
 
         case 2:
-            dllref = tcc_malloc(sizeof(DLLReference) + strlen(dllname));
+            dllref = tcc_mallocz(sizeof(DLLReference) + strlen(dllname));
             strcpy(dllref->name, dllname);
-            dllref->level = 0;
             dynarray_add((void ***) &s1->loaded_dlls, &s1->nb_loaded_dlls, dllref);
             ++state;