gplugin/gplugin

fix memory leaks in gplugin_file_source

14 months ago, Markus Fischer
d821f171d4c6
fix memory leaks in gplugin_file_source

leaks encountered:
## libpurple test_contact_info and test_person
```
==5998== 16 bytes in 1 blocks are definitely lost in loss record 1,996 of 6,277
==5998== at 0x48417E4: malloc (vg_replace_malloc.c:393)
==5998== by 0x4A6FA18: g_malloc (in /usr/lib64/libglib-2.0.so.0.7400.4)
==5998== by 0x4A88540: g_slice_alloc (in /usr/lib64/libglib-2.0.so.0.7400.4)
==5998== by 0x4A89675: g_slist_prepend (in /usr/lib64/libglib-2.0.so.0.7400.4)
==5998== by 0x4F0DA9E: gplugin_file_source_add_loader (gplugin-file-source.c:112)
==5998== by 0x4F0DCF1: gplugin_file_source_update_loaders (gplugin-file-source.c:179)
==5998== by 0x4F0E971: gplugin_file_source_constructed (gplugin-file-source.c:524)
==5998== by 0x49CF002: ??? (in /usr/lib64/libgobject-2.0.so.0.7400.4)
==5998== by 0x49D0C33: g_object_new_valist (in /usr/lib64/libgobject-2.0.so.0.7400.4)
==5998== by 0x49D1250: g_object_new (in /usr/lib64/libgobject-2.0.so.0.7400.4)
==5998== by 0x4F0EC51: gplugin_file_source_new (gplugin-file-source.c:607)
==5998== by 0x4F08019: gplugin_manager_refresh (gplugin-manager.c:874)
```
## gplugin tests
```
==23357== 456 (16 direct, 440 indirect) bytes in 1 blocks are definitely lost in loss record 535 of 557
==23357== at 0x48417E4: malloc (vg_replace_malloc.c:393)
==23357== by 0x48E4828: g_malloc (in /usr/lib64/libglib-2.0.so.0.7400.5)
==23357== by 0x48FD281: g_slice_alloc (in /usr/lib64/libglib-2.0.so.0.7400.5)
==23357== by 0x48FE6A8: g_slist_copy_deep (in /usr/lib64/libglib-2.0.so.0.7400.5)
==23357== by 0x485B252: gplugin_manager_find_plugins (gplugin-manager.c:934)
==23357== by 0x4861216: gplugin_file_source_scan (gplugin-file-source.c:349)
==23357== by 0x48622A9: gplugin_source_scan (gplugin-source.c:66)
==23357== by 0x485B041: gplugin_manager_refresh (gplugin-manager.c:881)
==23357== by 0x109464: test_gplugin_init_uninit_with_double_refresh_plugins (test-core.c:115)
==23357== by 0x49079DD: ??? (in /usr/lib64/libglib-2.0.so.0.7400.5)
==23357== by 0x490774C: ??? (in /usr/lib64/libglib-2.0.so.0.7400.5)
==23357== by 0x4907EE1: g_test_run_suite (in /usr/lib64/libglib-2.0.so.0.7400.5)
```

Testing Done:
Ran all gplugin tests and test_contact_info and test_person from libpurple in valgrind without encountering above leaks or any invalid reads/writes.

Reviewed at https://reviews.imfreedom.org/r/2255/
/*
* Copyright (C) 2011-2020 Gary Kramlich <grim@reaperworld.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <https://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <string.h>
#include <lauxlib.h>
#include <lua.h>
#include <lualib.h>
static void
_add_require_path(lua_State *L, const char *path)
{
const char *pkg_path = NULL;
char buff[255];
lua_getglobal(L, "package");
lua_getfield(
L,
-1,
"path"); // get field "path" from table at top of stack (-1)
pkg_path = lua_tostring(L, -1); // grab path string from top of stack
memset(buff, 0, sizeof(buff));
snprintf(buff, sizeof(buff), "%s;%s", pkg_path, path);
lua_pop(L, 1); // pop off the path field
lua_pushstring(L, buff); // push the new one
lua_setfield(L, -2, "path"); // set the field "path" in table at -2 with
// value at top of stack
lua_pop(L, 1); // get rid of package table from top of stack
}
int
main(int argc, char *argv[])
{
lua_State *L = NULL;
int ret = 0;
L = luaL_newstate();
if(L == NULL) {
return 134;
}
luaL_openlibs(L);
/* add some additional paths to package.path */
//_add_require_path(L, "/usr/local/lib/luarocks/rocks");
/* now try to do the require */
lua_getglobal(L, "require");
lua_pushstring(L, "lgi");
ret = lua_pcall(L, 1, 1, 0);
if(ret != 0) {
fprintf(stderr, "%s\n", lua_tostring(L, -1));
}
return ret;
}