CTL32 LIBCURL - NOT ENOUGH MEMORY...

[bournerj]

Hi

I'm currently implementing Carlos's Ctl32 libcurl library in our application and am experiencing some strange behaviour on the 26th call to the function -- namely, the "There is not enough memory to complete this operation." error.

As far as I'm aware, I'm cleaning up as I should and I've seen this error before with errors that weren't actually caused by memory leaks so I'm not 100% convinced that it's a leak.

I can replicate this behaviour and have separated everything out so it is just this code that is running -- every 26th call creates this error and then I have to close the IDE in order to be able to run a successful call again -- this is even after running the following:

CLEAR ALL
CLEAR RESOURCES
CLEAR MEMORY
SET DEFAULT TO
SET CLASSLIB TO
CLOSE ALL
RELEASE ALL

This is me using my own wrapper to run a simple GET on our website:

SET PROCEDURE TO RC_Curl ADDITIVE

loRCCurl = CREATEOBJECT("RCCurl", "[URL unfurl="true"]https://rushcliff.com")[/URL]
loRCCurl.Get()

IF loRCCurl.bGotAnError
	??loRCCurl.cError
	RETURN .f.
ENDIF

??loRCCurl.cReturn

RELEASE loRCCurl
RELEASE PROCEDURE RC_Curl

The RCCurl class:

DEFINE CLASS RCCurl AS Custom
	PROTECTED oCurl, oError, nResultCode, cRawReturn
	oCurl = .null.
	oError = .null.
	nResultCode = -1
	cRawReturn = ""
	
	bGotAnError = .f.
	cError = ""
	cReturn = ""
	
	FUNCTION Init
		PARAMETERS cURL

		DO libcurl.prg

		this.oCurl = CREATEOBJECT("libcurl")
		
		IF !EMPTY(cURL)
			this.SetURL(cURL)
		ENDIF
		
		this.oCurl.CurlOptSslVerifyHost = .f.
		this.oCurl.CurlOptSslVerifyPeer = .f.
		
		RETURN .t.
	ENDFUNC
	
	FUNCTION Destroy
		this.oCurl = .null.
		RELEASE CLASSLIB libcurl.vcx
	ENDFUNC
	
	PROTECTED FUNCTION SetError
		PARAMETERS cError
		
		this.bGotAnError = .t.
		this.cError = "Error: " + ALLTRIM(cError)
	ENDFUNC
	
	FUNCTION GetURL
		RETURN this.oCurl.CurlOptURL
	ENDFUNC
	
	FUNCTION SetURL
		PARAMETERS cURL
		
		this.oCurl.CurlOptURL = cURL
	ENDFUNC
	
	PROTECTED FUNCTION WeGotAnError
		RETURN .f.
	ENDFUNC
	
	PROTECTED FUNCTION Run
		IF EMPTY(this.GetURL())
			this.SetError("Destination URL is not set.")
			RETURN .f.
		ENDIF
		
		*!* Run that thang.
		this.nResultCode = this.oCurl.CurlEasyPerform()
		
		IF this.nResultCode <> 0
			*!* Error!
			this.SetError(ALLTRIM(STR(this.nResultCode)) + " " + this.oCurl.CurlEasyStrError(this.nResultCode))
			RETURN .f.
		ENDIF
		
		this.cReturn = this.oCurl._databuffer
		
		RETURN .t.
	ENDFUNC
	
	*!* HTTP GET
	FUNCTION Get
		PARAMETERS cURL
		
		IF !EMPTY(cURL)
			this.SetURL:cURL)
		ENDIF
		
		this.oCurl.CurlOptHttpGet = .t.

		IF !this.Run()
			RETURN .f.
		ENDIF
		
		IF this.WeGotAnError()
			RETURN .f.
		ENDIF
		
		RETURN .t.
	ENDFUNC
ENDDEFINE

The libcurl.prg and .vcx have not been modified.

The line that causes this error (called from rccurl.init >> rccurl.seturl >> libcurl.curlopt_assign >> libcurl.curlglobalinit >> libcurl._createcallbacks) is:

This._DebugCallBackPtr = ;
CreateCallBackFunc("_DebugCallback","INTEGER","INTEGER,INTEGER,INTEGER,INTEGER,INTEGER", This, 1)

if I ignore on that line, the subsequent CreateCallBackFunc calls produce the same error.

For reference, my development machine is W7 64-bit.

Any help is greatly appreciated, many thanks in advance.

Richard

 

[Olaf Doschke]

Hi Richard,

I have a typo there in this.SetURL:cURL), but no, that's not the fix.
I can reproduce, but I get the memory error at DestroyCallbackFunc in _destroycallbacks method of the libcurl class in libcurl.vcx
I can't tell you what's wrong, I don't know if this usage of getting at _databuffer is correct, the underline seems to indicates an internal property, but it's obviously not private or hidden.
The usaual use of curls easyperform is in conjunction with a callback function, as it works asynchhronous, you get parts of the currently running operation(s).

Maybe use HttpDownloadFile instead.

Bye, Olaf.

 

[bournerj]

Hi Olaf

Thanks for your response.

The typo isn't in my actual code, must have found its way in during copy/paste.

Interesting, it is on CreateCallBackFunc every time for me.

I'll look at the callback option then, thanks.

I want to set up for running POST and PUT calls as well so thought this would be the best option. Failing that I'll probably use Rick's wwClient.

Thanks again,

Richard