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9730 :: "SIGSEGV: illegal storage access" (httpclient)

• RexStewart (orginal) [2022-12-15T22:10:14+01:00] view original

  hello everyone,

  NIM newbie here, i'm getting "SIGSEGV: illegal storage access" (attempt to read from nil?) crash randomly. i have been trying to find what's causing it but i can't.

  • i'm building on Windows 7 x64
  • crashing functions seem to be related to std/httpclient
  • it can crash in 1 hour or 1 day randomly without any sign
  • tested both builds x64 and x86 (32bits current)
  • tested on nim-1.6.0 and nim-1.6.10 (32bits current)
  • tested on Win 7 and Win 10 (both crashed)
  • tested also with --mm:arc -d:useMalloc (not sure if it was related, but crashed as well)
  • my app logs don't show anything weird coming from the web server (like garbage or something similar)
  • i added a timeout at 25000
  • i added the "check_server" function before doing normal get, post, download, etc to make sure the server is reachable before the other requests (maybe there is a better way to do it)

  below are the code snippets i'm using and the crash trace backs' screenshots. what's wrong? thank you in advance

  https://imgur.com/a/bdVCJbh https://imgur.com/a/SUtjEpa

  # GET
  proc http_get_data(params: string): string =
    var obj_response: Response
    
    # CHECK SERVER
    check_server()
    
    var client = newHttpClient(timeout = HTTP_TIMEOUT)
    var full_url = main_server & api_path & "?" & params
    
    try:
      obj_response = client.get(full_url)
    except OSError:
      when DEBUG:
        log_local("[!] http_get_data() FAILED / OSError EXCEPTION RAISED.", log_http)
      return ""
    except:
      when DEBUG:
        log_local("[!] http_get_data() FAILED / EXCEPTION RAISED.", log_http)
      return ""
    finally:
      client.close()
    
    if obj_response == nil:
      when DEBUG:
        log_local("[!] http_get_data() NIL RESPONSE/OBJECT EXITING.", log_http)
      return ""
    
    var data = obj_response.body
    
    when DEBUG:
      log_local("http_get_data() GET: "&params, log_http)
      log_local("http_get_data() URL: "&full_url, log_http)
      log_local("http_get_data() REPONSE: "&data, log_http)
    
    return data
  
  
  # CHECK SERVER
  proc check_server() =
    var full_url = main_server & api_path & "?id=6"
    var obj_response: Response
    
    while true:
      var client = newHttpClient(timeout = HTTP_TIMEOUT) # 25 seconds
      try:
        obj_response = client.get(full_url)
        if obj_response != nil and obj_response.body == SERVERUP:
          when DEBUG:
            log_local("check_server() HTTP CODE: "&obj_response.status, log_server)
            log_local("check_server() HTTP BODY: "&obj_response.body, log_server)
            log_local("check_server() SERVER IS UP!", log_server)
          return
      except OSError:
        when DEBUG:
          log_local("[!] SERVER NOT FOUND OR DOWN. RETRYING. OSError RAISED.", log_server)
      except:
        when DEBUG:
          log_local("[!] SERVER NOT FOUND OR DOWN. RETRYING. SOME EXCEPTION RAISED.", log_server)
      finally:
        client.close()
      
      sleep(3000)
  Run

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