Fix shlib loaded: free memory, handle lib reload

- introduce loader_reset() that frees all memory
- resolve memory leak in loader_format_shlibpath()
- correctly handle library reload: check if a function has been
  retrieved already. Don't leak memory (strdup()), and handle multiple
  reloads of different functions from the same SO

common/utils/load_module_shlib.c

@@ -69,7 +69,6 @@ char *loader_format_shlibpath(char *modname, char *version)
 char *tmpstr;
 char *shlibpath   =NULL;
 char *shlibversion=NULL;
-char *cfgprefix;
 paramdef_t LoaderParams[] ={{"shlibpath", NULL, 0, strptr:&shlibpath, defstrval:NULL, TYPE_STRING, 0, NULL},
                             {"shlibversion", NULL, 0, strptr:&shlibversion, defstrval:"", TYPE_STRING, 0, NULL}};
 
@@ -81,16 +80,11 @@ int ret;
 /* looks for specific path for this module in the config file */
 /* specific value for a module path and version is located in a modname subsection of the loader section */
 /* shared lib name is formatted as lib<module name><module version>.so */
-  cfgprefix = malloc(sizeof(LOADER_CONFIG_PREFIX)+strlen(modname)+16);
-  if (cfgprefix == NULL) {
-      fprintf(stderr,"[LOADER] %s %d malloc error loading module %s, %s\n",__FILE__, __LINE__, modname, strerror(errno));
-      exit_fun("[LOADER] unrecoverable error");
-  } else {
-      sprintf(cfgprefix,LOADER_CONFIG_PREFIX ".%s",modname);
-      int ret = config_get( LoaderParams,sizeof(LoaderParams)/sizeof(paramdef_t),cfgprefix);
-      if (ret <0) {
-          fprintf(stderr,"[LOADER]  %s %d couldn't retrieve config from section %s\n",__FILE__, __LINE__,cfgprefix);
-      }
+  char cfgprefix[sizeof(LOADER_CONFIG_PREFIX)+strlen(modname)+16];
+  sprintf(cfgprefix,LOADER_CONFIG_PREFIX ".%s",modname);
+  ret = config_get( LoaderParams,sizeof(LoaderParams)/sizeof(paramdef_t),cfgprefix);
+  if (ret <0) {
+      fprintf(stderr,"[LOADER]  %s %d couldn't retrieve config from section %s\n",__FILE__, __LINE__,cfgprefix);
    }
 /* no specific path, use loader default shared lib path */
    if (shlibpath == NULL) {
@@ -142,6 +136,7 @@ int load_module_version_shlib(char *modname, char *version, loader_shlibfunc_t *
   }
 
   shlib_path = loader_format_shlibpath(modname, version);
+  printf("shlib_path %s\n", shlib_path);
 
   for (int i = 0; i < loader_data.numshlibs; i++) {
     if (strcmp(loader_data.shlibs[i].name, modname) == 0) {
@@ -198,15 +193,17 @@ int load_module_version_shlib(char *modname, char *version, loader_shlibfunc_t *
   }
 
   if (farray) {
-    if (!loader_data.shlibs[lib_idx].funcarray) {
-      loader_data.shlibs[lib_idx].funcarray = malloc(numf*sizeof(loader_shlibfunc_t));
-      if (!loader_data.shlibs[lib_idx].funcarray) {
+    loader_shlibdesc_t *shlib = &loader_data.shlibs[lib_idx];
+    if (!shlib->funcarray) {
+      shlib->funcarray = calloc(numf, sizeof(loader_shlibfunc_t));
+      if (!shlib->funcarray) {
         fprintf(stderr, "[LOADER] load_module_shlib(): unable to allocate memory\n");
         ret = -1;
         goto load_module_shlib_exit;
       }
+      shlib->len_funcarray = numf;
+      shlib->numfunc = 0;
     }
-    loader_data.shlibs[lib_idx].numfunc = 0;
     for (int i = 0; i < numf; i++) {
       farray[i].fptr = dlsym(lib_handle,farray[i].fname);
       if (!farray[i].fptr) {
@@ -215,9 +212,32 @@ int load_module_version_shlib(char *modname, char *version, loader_shlibfunc_t *
         ret = -1;
         goto load_module_shlib_exit;
       }
-      loader_data.shlibs[lib_idx].funcarray[i].fname=strdup(farray[i].fname);
-      loader_data.shlibs[lib_idx].funcarray[i].fptr = farray[i].fptr;
-      loader_data.shlibs[lib_idx].numfunc++;
+      /* check whether this function has been loaded before */
+      int j = 0;
+      for (; j < shlib->numfunc; ++j) {
+        if (shlib->funcarray[j].fptr == farray[i].fptr) {
+          int rc = strcmp(shlib->funcarray[i].fname, farray[i].fname);
+          AssertFatal(rc == 0,
+                      "reloading the same fptr with different fnames (%s, %s)\n",
+                      shlib->funcarray[i].fname, farray[i].fname);
+          break;
+        }
+      }
+      if (j == shlib->numfunc) {
+        if (shlib->numfunc == shlib->len_funcarray) {
+          loader_shlibfunc_t *n = reallocarray(shlib->funcarray, shlib->numfunc * 2, sizeof(loader_shlibfunc_t));
+          if (!n) {
+            fprintf(stderr, "[LOADER] %s(): unable to allocate memory\n", __func__);
+            ret = -1;
+            goto load_module_shlib_exit;
+          }
+          shlib->funcarray = n;
+          shlib->len_funcarray = shlib->numfunc * 2;
+        }
+        shlib->funcarray[j].fname = strdup(farray[i].fname);
+        shlib->funcarray[j].fptr = farray[i].fptr;
+        shlib->numfunc++;
+      }
     } /* for int i... */
   } else {  /* farray ! NULL */
     sprintf(afname,"%s_getfarray",modname);
@@ -248,3 +268,18 @@ void * get_shlibmodule_fptr(char *modname, char *fname)
     } /* for i loop on modules */
     return NULL;
 }
+
+void loader_reset()
+{
+  for (int i = 0; i < loader_data.numshlibs && loader_data.shlibs[i].name != NULL; i++) {
+    loader_shlibdesc_t *shlib = &loader_data.shlibs[i];
+    free(shlib->name);
+    free(shlib->thisshlib_path);
+    for (int j = 0; j < shlib->numfunc; ++j)
+      free(shlib->funcarray[j].fname);
+    free(shlib->funcarray);
+    shlib->numfunc = 0;
+    shlib->len_funcarray = 0;
+  }
+  free(loader_data.shlibs);
+}

common/utils/load_module_shlib.h

@@ -47,6 +47,7 @@ typedef struct {
    char               *thisshlib_path;
    uint32_t           numfunc;
    loader_shlibfunc_t *funcarray;
+   uint32_t           len_funcarray;
 }loader_shlibdesc_t;
 
 typedef struct {
@@ -90,5 +91,6 @@ extern void * get_shlibmodule_fptr(char *modname, char *fname);
 extern loader_data_t loader_data;
 #endif /* LOAD_MODULE_SHLIB_MAIN */
 #define load_module_shlib(M, F, N, I) load_module_version_shlib(M, NULL, F, N, I)
+void loader_reset();
 #endif
 

openair1/SIMULATION/NR_PHY/dlschsim.c

@@ -29,6 +29,7 @@
 #include "common/config/config_userapi.h"
 #include "common/utils/LOG/log.h"
 #include "common/utils/LOG/vcd_signal_dumper.h"
+#include "common/utils/load_module_shlib.h"
 #include "T.h"
 #include "PHY/defs_gNB.h"
 #include "PHY/defs_nr_common.h"
@@ -671,6 +672,8 @@ int main(int argc, char **argv)
 	if (ouput_vcd)
         vcd_signal_dumper_close();
 
+  loader_reset();
+
 	return (n_errors);
 }