RFR: JDK-8320005 : Native library suffix impact on hotspot code in AIX [v2]

[suchismith1993]

On Mon, 27 Nov 2023 11:36:02 GMT, suchismith1993 <duke at openjdk.org> wrote:

> > > i would have to repeat the line 1132 and 1139 in os_aix.cpp again , if the condition fails for .so files, because i have to reload it again and check if the .a exists. In the shared code i had repeat less number of lines i believe. Do you suggest moving lines 1132 to 1139 to another function then ?
> > 
> > 
> > @tstuefe Any suggestion on this ?
> 
> ```
> --- a/src/hotspot/os/aix/os_aix.cpp
> +++ b/src/hotspot/os/aix/os_aix.cpp
> @@ -1108,7 +1108,7 @@ bool os::dll_address_to_library_name(address addr, char* buf,
>    return true;
>  }
>  
> -void *os::dll_load(const char *filename, char *ebuf, int ebuflen) {
> +static void* dll_load_inner(const char *filename, char *ebuf, int ebuflen) {
>  
>    log_info(os)("attempting shared library load of %s", filename);
>  
> @@ -1158,6 +1158,35 @@ void *os::dll_load(const char *filename, char *ebuf, int ebuflen) {
>    return nullptr;
>  }
>  
> +void* os::dll_load(const char *filename, char *ebuf, int ebuflen) {
> +
> +  void* result = nullptr;
> +
> +  // First try using *.so suffix; failing that, retry with *.a suffix.
> +  const size_t len = strlen(filename);
> +  constexpr size_t safety = 3 + 1;
> +  constexpr size_t bufsize = len + safety;
> +  char* buf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
> +  strcpy(buf, filename);
> +  char* const dot = strrchr(buf, '.');
> +
> +  assert(dot != nullptr, "Attempting to load a shared object without extension? %s", filename);
> +  assert(strcmp(dot, ".a") == 0 || strcmp(dot, ".so") == 0,
> +      "Attempting to load a shared object that is neither *.so nor *.a", filename);
> +
> +  sprintf(dot, ".so");
> +  result = dll_load_inner(buf, ebuf, ebuflen);
> +
> +  if (result == nullptr) {
> +    sprintf(dot, ".a");
> +    result = dll_load_inner(buf, ebuf, ebuflen);
> +  }
> +
> +  FREE_C_HEAP_ARRAY(char, buf);
> +
> +  return result;
> +}
> +
> ```

@tstuefe  as discussed with @TheRealMDoerr do you think using default argument will help ? 
Either we pass agent object as 3rd parameter or an empty character buffer(and not const chat*)  which would be spcifically used to copy the alternate filename to it using strcpy so that it is reflected in the jvmagent code ?

-------------

PR Comment: https://git.openjdk.org/jdk/pull/16604#issuecomment-1828086180