Create a new patch file for each patch and close old handle

This stopped a few misbehaviours

src/moduler/moduler.c

@@ -19,8 +19,15 @@
 #include <stdalign.h>
 #include <stdbool.h>
 #include <sys/mman.h>
+#include <time.h>
 #include <unistd.h>
 
+typedef struct {
+  const char *filename;
+  void *dlhandle;
+  MemoryRegionSpan memreg;
+} PatchData;
+
 static void *adjust_if_relative(void *ptr, void *module_base) {
   uptr p = (uptr)ptr;
   if (p && (p < (uptr)module_base)) {
@@ -131,8 +138,8 @@ static HiloadResult gather_patchable_symbols(struct sc_array_sym *symbols,
         }
 
         void *sym_addr = (void *)((uintptr_t)module_base + sym.st_value);
-        HiSymbolBind binding = symbol_bind_from_efi(GELF_ST_BIND(sym.st_info));
+        HiSymbolBind binding = symbol_bind_from_efibind(GELF_ST_BIND(sym.st_info));
-        HiSymbolType type = symbol_type_from_efi(GELF_ST_TYPE(sym.st_info));
+        HiSymbolType type = symbol_type_from_efitype(GELF_ST_TYPE(sym.st_info));
         size_t size = sym.st_size;
 
         // Gather global symbols and local object symbols. Local functions are
@@ -268,6 +275,36 @@ static HiloadResult moduler_apply_module_patch(HiSymbols *psymbols,
   return HILOAD_OK;
 }
 
+PatchData moduler_create_patch(HiModuleData *module) {
+
+  time_t now = time(NULL);
+  struct tm *t = localtime(&now);
+  if (t == NULL) {
+    return (PatchData){0};
+  }
+
+  char file_append[32];
+  if (strftime(file_append, sizeof(file_append), ".%Y%m%d%H%M%S.patch", t) == 0) {
+    log_error("Failed to create patch filename.\n");
+    return (PatchData){0};
+  }
+
+  char filename[512];
+  size_t written =
+      hi_strncat_buf(sizeof(filename), filename, module->name, file_append);
+
+
+  if (written == 0) {
+    log_error("Failed to concat %s and %s\n", module->name, ".patch");
+    return (PatchData){0};
+  }
+
+  hi_file_copy(module->name, filename);
+
+  PatchData data = {.filename = strdup(filename)};
+  return data;
+}
+
 HiloadResult moduler_reload(HiModuleArray *modules, HiModuleData *module,
                             struct sc_array_memreg *memregs) {
 
@@ -279,40 +316,36 @@ HiloadResult moduler_reload(HiModuleArray *modules, HiModuleData *module,
     return HILOAD_OK;
   }
 
-  dlerror(); // clear old errors
+  PatchData patch = moduler_create_patch(module);
-  char patch_filename[512];
+  if (!patch.filename) {
-  size_t written = hi_strncat_buf(sizeof(patch_filename), patch_filename,
+    log_error("Couldn't create patch for %s\n", module->name);
-                                  module->name, ".patch");
-  if (written == 0) {
-    log_error("Failed to concat %s and %s\n", module->name, ".patch");
     return HILOAD_FAIL;
   }
 
-  hi_file_copy(module->name, patch_filename);
-
   // Load patch
-  log_debug("Opening: %s\n", patch_filename);
+  dlerror(); // clear any previous errors
-  void *new_handle = dlopen(patch_filename, RTLD_LAZY);
+  log_debug("Opening: %s\n", patch.filename);
+  void *new_handle = dlopen(patch.filename, RTLD_LAZY);
   if (!new_handle) {
     log_error("Couldn't load: %s\n", dlerror());
     module->info = hi_modinfo_clear(module->info, HI_MODULE_STATE_DIRTY);
     return HILOAD_FAIL;
   }
+  patch.dlhandle = new_handle;
 
   // refresh cache
   read_memory_maps_self(memregs);
 
-  MemoryRegionSpan patch_memory =
+  patch.memreg = memory_get_module_span(memregs, patch.filename);
-      memory_get_module_span(memregs, patch_filename);
+  void *patch_base = (void *)patch.memreg.region_start;
-  void *patch_base = (void *)patch_memory.region_start;
 
   HiSymbols patch_symbols;
   symbol_init_symbols(&patch_symbols);
 
   HiloadResult ret =
-      gather_patchable_symbols(&patch_symbols, patch_filename, patch_base);
+      gather_patchable_symbols(&patch_symbols, patch.filename, patch_base);
   if (!HIOK(ret)) {
-    log_error("Failed to gather symbols for %s\n", patch_filename);
+    log_error("Failed to gather symbols for %s\n", patch.filename);
     return HILOAD_FAIL;
   }
 
@@ -327,7 +360,7 @@ HiloadResult moduler_reload(HiModuleArray *modules, HiModuleData *module,
 
     // If patch is for the same module, also collect local object symbols for
     // coping those over
-    if (strncmp(mod.name, patch_filename, strlen(mod.name)) == 0) {
+    if (strncmp(mod.name, patch.filename, strlen(mod.name)) == 0) {
 
       HiSymbols module_symbols;
       symbol_init_symbols(&module_symbols);
@@ -360,7 +393,11 @@ HiloadResult moduler_reload(HiModuleArray *modules, HiModuleData *module,
     module->info = hi_modinfo_clear(module->info, HI_MODULE_STATE_DIRTY);
   }
 
+  free((char*)patch.filename);
   symbol_term_symbols(&patch_symbols);
 
+  dlclose(module->dlhandle);
+  module->dlhandle = patch.dlhandle;
+
   return HILOAD_OK;
 }

src/symbols.c

@@ -15,7 +15,7 @@ HiSymbol *symbol_find(HiSymbols *symbols, HiSymbol *symbol) {
   return NULL;
 }
 
-HiSymbolBind symbol_bind_from_efi(u32 efi_bind) {
+HiSymbolBind symbol_bind_from_efibind(u32 efi_bind) {
   // clang-format off
   switch (efi_bind) {
     case STB_LOCAL: return HI_SYMBOL_BIND_LOCAL;
@@ -26,7 +26,7 @@ HiSymbolBind symbol_bind_from_efi(u32 efi_bind) {
   return ~0u;
 }
 
-HiSymbolType symbol_type_from_efi(u32 efi_type) {
+HiSymbolType symbol_type_from_efitype(u32 efi_type) {
   // clang-format off
   switch (efi_type) {
     case STT_NOTYPE: return HI_SYMBOL_TYPE_NOTYPE;   /* Symbol type is unspecified */

src/symbols.h

@@ -52,6 +52,6 @@ static inline void symbol_term_symbols(HiSymbols *symbols) {
 
 HiSymbol *symbol_find(HiSymbols *symbols, HiSymbol *symbol);
 
-HiSymbolBind symbol_bind_from_efi(u32 efi_bind);
+HiSymbolBind symbol_bind_from_efibind(u32 efi_bind);
-HiSymbolType symbol_type_from_efi(u32 efi_type);
+HiSymbolType symbol_type_from_efitype(u32 efi_type);
 #endif // SYMBOLS_H_

test/manual/minimal.cpp

@@ -18,7 +18,7 @@ int main(int argc, char *argv[]) {
   while (modified != 0) {
 
     modified = minimal_lib::getNewValue(5);
-    printf("getNewValue(5): %d\n", modified);
+    printf("getNewValue: %d\n", modified);
     std::this_thread::sleep_for(std::chrono::seconds(1));
 
     printf("otherValue: %d\n", minimal_lib::otherValue++);

test/manual/minimal_lib.cpp

@@ -1,10 +1,11 @@
 #include "minimal_lib.h"
+#include <cstdio>
 
 namespace minimal_lib {
 
 int getNewValue(int x) {
   static int value = 0;
-  value = value + 5;
+  value = value + x;
   return value;
 }