Thread: File Server Help - Part 2

<< split from overweight and old thread - http://cboard.cprogramming.com/showthread.php?t=106820 ; It's not your personal support thread >>

Can somebody check my code please?
I'm getting segmentation error
Fileserver
http://pastebin.php-es.info/95292
Fileclient <- Just take a look at the sendfile function.. I think it's correct
http://pastebin.php-es.info/95293

> I'm getting segmentation error
So run it in the debugger, and trap the place where it happens.
Then start thinking about causes.

And already, your poor indentation skills are making the code next to impossible to read (so I didn't bother).

Your crappy pastebin site is just making it too hard to care about helping you.

> tmpmemfiles = realloc(memfiles, (connected * sizeof(struct _fileinfo)));
> free(memfiles);

realloc WILL free the memory if it moves, you don't need to do anything here.

> recv(*sock, buff, sizeof(buff), 0);
1. You don't check the return result.
2. recv doesn't add a \0, unless you send one
3. your buff is initialused to garbage
4. your strlen probably wanders off into the weeds at some point.

Thanks, I've corrected it, what about the error that the program freezes after cheking for password?
It does the following:
1) Accepts the connection
2) Checks for password
3) It's like waiting for something to recv or send
4) If the client starts sending the file I get segmentation error, maybe the error is on the send() function, to check if the password is correct.. but it sends correctly that is correct

Originally Posted by master5001

Also be aware of the fact that its possible memfiles == tmpmemfiles!!! So you may very likely just be freeing your buffer.

Yes, and if it's NOT, you are "double-freeing", so that could easily cause a crash or other spurious behaviour.

--
Mats

We've been over this before.

> recv(*sock, buff, sizeof(buff), 0);
1. You don't check the return result.
2. recv doesn't add a \0, unless you send one
3. your buff is initialused to garbage
4. your strlen probably wanders off into the weeds at some point.

Make sure you have a proper string with an in-bound \0 before you start using ANY str... function on it.

Yeah shure, but the thing is that it's not even executing the printf()

Code:

        void newfile(int *sock) {
	printf("New file created");
	char buff[512];
	char filepath[128];
	long int totalparts;
	char *p;
	int i, len;
	i = *sock;
	len = recv(*sock, buff, sizeof(buff), 0);
	printf("Recieved of path: %i", len);
	strcat(buff, "\0");
	p=strtok(buff, "=");
	p=strtok(NULL, ";");
	strcpy(filepath, p);
	p=strtok(NULL, "=");
	p=strtok(NULL, ";");
	totalparts=strtol(p,NULL,10);
	if((memfiles[i].file=fopen(filepath, "ab"))) {
		memfiles[i].exists=1;
		memfiles[i].parts=0;
		memfiles[i].totalparts=totalparts;
	}
	else {
		printf("Error on creating new file");
	}
}

Printed things

Code:

Server Change
Socket Creado
Port 3000 bindeado
Socket Listeneando
Select starteado
Nueva conexion.. testeando pass
Client Passwd: lol and lenght: 3
Server Passwd: lol and lenght: 3 
Que da el cmp: 0 
Password correcta
newfd = 4 y fdmax = 3 
Alocando memfiles
Total Connected = 1 
Alocado memfiles 
Seteando memfiles en socket 3
Select starteado
Existant connection incomming from set = 4 
Recieving new file from = 4 
Fallo de segmentación

Mmm.. do you know any library that has a getpixel() function like the windows one?

> Yeah shure, but the thing is that it's not even executing the printf()
a) you don't have a newline
b) you don't call fflush(stdout) either
c) the result is the printed message is in a buffer somewhere.

> strcat(buff, "\0");
Oh jeez, what part of "before you start using ANY str... function on it" didn't you understand?
Do you even know what strcat does?
Search for a \0 is the first thing it does, so using strcat to find a \0, to append a \0 is just bone-headed.
Look at master5001's reply above, that's what you should be doing.