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pointer and struct allocation

drazenmozart (21)
hello!!
i my source code i use the following structs:
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typedef struct
{
uint8_t source;
uint8_t destination;
}IP4Hdr;

typedef struct 
{
IP4Hdr *ip4h;
uint16_t src_port;
uint16_t dst_port;
int packets;
int is_here;
}Flows;

typedef struct
{
IP4Hdr *ip4h;
float num_flows;	//for each ip
int is_here;
}IPs;

typedef struct 
{
Flows *flows;
IPs *ips;
}Slots;


at a point, i declare a pointer to these structs. Now, to allocate the IPS* and Flows* i do the following:
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Flows* flows = calloc(MAXFLOWS, sizeof(*flows));
    for(i = 0; i < MAXFLOWS; i++)
{
    flows[i].ip4h = calloc(1, sizeof( *(flows[i].ip4h) ) );
}
and same thing for IPs*. But when i do something similar for the Slots*:
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Slots* slots = calloc(MAXSLOTS, sizeof(*slots));

for (j=0;j<MAXSLOTS;j++){
     slots[MAXSLOTS].flows=calloc(MAXFLOWS, sizeof(*(slots[MAXSLOTS].flows)));
	for(i = 0; i < MAXFLOWS; i++)
        {
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        }
    slots[MAXSLOTS].ips=calloc(MAXIPS, sizeof(*(slots[MAXSLOTS].ips)));
	for(i = 0; i < MAXIPS; i++)
	{
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	}
}

i get an error for 8 and 13 line for undeclared 'flows' and undeclared 'ips'

what am i missing??
thanks!!
Last edited on
Peter87 (11228)
I think this is closer to what you want:
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Slots* slots = calloc(MAXSLOTS, sizeof(Slots));
for (j=0;j<MAXSLOTS;j++)
{
	slots[j].flows=calloc(MAXFLOWS, sizeof(Flows));
	for(i = 0; i < MAXFLOWS; i++)
	{
		slots[j].flows[i].ip4h = calloc(1, sizeof(IP4Hdr) );
	}
	slots[j].ips=calloc(MAXIPS, sizeof(IPs));
	for(i = 0; i < MAXIPS; i++)
	{
		slots[j].ips[i].ip4h = calloc(1, sizeof(IP4Hdr) );
	}
}

Last edited on
drazenmozart (21)
you 're right!!!! thanks a lot Peter!
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