Initializing a struct results in Segmentation Fault - c

Question

I have a simple struct as follows:
typedef struct {
char *raw_headers;
char headers[128][512][512];
} HTTPrequest;
Now in the same file I have a function as follows:
void init_request(char *raw_headers) {
HTTPrequest request;
request.raw_headers = raw_headers;
}
This results in a Segmentation Fault when running the output binary.
I compile the file, as
$ gcc Server.c -o Builds/debug
And, I run the executable as,
$ ./Builds/debug
This is my original file as requested:
Parser.h
typedef struct {
char *raw_headers;
char headers[128][512][512];
} HTTPrequest;
void parser_init(char *raw_headers) {
char *token, *key_value = NULL;
token = strtok(raw_headers, "\r\n");
int line_counter = 1
HTTPrequest request;
request.raw_headers = raw_headers;
while (token) {
char *line = token;
if(line_counter != 1) {
}
token = strtok(NULL, "\r\n");
line_counter++;
}
}
Server.h
int socket_create() {
return socket(AF_INET, SOCK_STREAM, 0);
}
void infinite_loop(int socketFD) {
char buffer[1024];
memset(buffer, 0, sizeof(buffer));
printf("Starting infinite loop, don't worry, everything would be okay!\n");
do {
int connectionFD = accept(socketFD, (struct sockaddr*) NULL, NULL);
/*Accept is a blocking call! The following code wont execute until, accept() returns.*/
strcpy(buffer, "HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\nHello!");
write(connectionFD, buffer, sizeof(buffer));
char request[2048];
memset(&request, 0, sizeof(request));
read(connectionFD, &request, sizeof(request));
printf("Request received!\n");
// Init the parser.
parser_init(request);
close(connectionFD);
} while (true);
}
Server.c
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <stdbool.h>
#include "Parser.h"
#include "Server.h"
void main() {
struct sockaddr_in listeningAddr;
int socketFD = socket_create();
memset(&listeningAddr, 0, sizeof(listeningAddr));
listeningAddr.sin_family = AF_INET;
listeningAddr.sin_addr.s_addr = htonl(INADDR_ANY);
listeningAddr.sin_port = htons(8070);
bind(socketFD, (struct sockaddr*) &listeningAddr, sizeof(listeningAddr));
if(listen(socketFD, 5) == -1) {
printf("Woah there! I couldn't startup the server!");
}
infinite_loop(socketFD);
}
Also, the error message: Segmentation fault (core dumped)

Answer 1

The headers member (32MiB) makes your struct too big to fit on most default system-provided stacks (8MiB on Linux).
Make it smaller, and trivial MCVEs such as:
typedef struct {
char *raw_headers;
char headers/*[128]*/[512][512]; }
HTTPrequest;
void init_request(char *raw_headers) {
HTTPrequest request;
request.raw_headers = raw_headers;
}
int main()
{
init_request("hello, world");
}
will work, although, initializing an on-stack struct only to have it discarded by the function return is not very meaningful
(Initializer functions will usually take a pointer to the struct they're initializing and initialize the object through that pointer.)

Answer 2

Although your HTTPrequest is simple, it is over 32MB in size. You most probably encounter a stack overflow...

Answer 3

That's a typical case of Stack overflow!
The reason is that your struct HTTPrequest is too big, more than 32 MB. The 3D array has a size of 128 * 512 * 512 = 33554432 bytes, since it's of type char.
In any case, 3D arrays are barely used, and only in special cases. Reconsider your design and try to make that array a 2D instead of a 3D.