I have this program that i can run with a port number then in browser do something like localhost:port/image.jpg and it will open the image. However i want to try and do this using threads.
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <strings.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/stat.h>
#define BufferSize 1024 // for parsing request
#define BIG_ENUF 4096 // For request header
void error(char *); // prototype for quick error exit
int main(int argc, char *argv[]) // arv[1] has port #
{
int sockfd, newsockfd, portno, clilen,Connect_Count=0;
char buffer[BufferSize]; // for communicating with client
char * BigBuffer; // for serving file to client
int BufferNdx,n ;// workaday subscripts
char * TmpBuffer, *SavePtr, *FileName, *GetToken;
pid_t pid; // for forks;
FILE * F; // for streaming file when GET served
struct stat S;// to find file length
struct sockaddr_in serv_addr, cli_addr;
// structs for client and server
if (argc < 2) { // looking for port #
fprintf(stderr,"ERROR, no port provided\n");
exit(1);
}
sockfd = socket(AF_INET, SOCK_STREAM, 0);
// specifies TCP IP flow
if (sockfd < 0)error("ERROR opening socket");
memset( (char *) &serv_addr, 0, sizeof(serv_addr));
portno = atoi(argv[1]);
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = INADDR_ANY;
serv_addr.sin_port = htons(portno); // proper byte order
if (bind(sockfd, (struct sockaddr *) &serv_addr,sizeof(serv_addr)) < 0)
error("ERROR on binding");
GetToken = strtok_r(TmpBuffer," ",&SavePtr);
// And Now port is bound to socket for TCP / IP
while (Connect_Count < 10) // Limit on Number of Connections
{listen(sockfd,5);
clilen = sizeof(cli_addr);
newsockfd = accept(sockfd, (struct sockaddr *) &cli_addr, &clilen);
// listen blocks until someone knocks and when we accept
// the client structure is filled by accept
if (newsockfd < 0) // exit server if bad accept
error( "ERROR on accept");
// otherwise let's fork a process to do that work
pid = fork();
if (pid < 0) error("bad fork\n");
if (pid == 0) break;
// to handle talking with client below
//if parent, loop again to listen if more connections ?
}
// ===================================================
// Forked child
memset(buffer, 0,BufferSize);
n = read(newsockfd,buffer,BufferSize-1); // This leaves null at end
if (n < 0) error("ERROR reading from socket");
printf("%s\n",(TmpBuffer=strtok_r(buffer,"\n",&SavePtr)));
GetToken = strtok_r(TmpBuffer," ",&SavePtr);
printf("%s\n",GetToken);
GetToken = strtok_r(NULL," ",&SavePtr);
printf("%s After Get\n",GetToken); // file name token begins '/'
GetToken++; // Point to first character of actual file name
// now open the file and send it to client ?
if ((F = fopen(GetToken,"r")) == NULL) error("Bad\n");
else printf("Good\n");
int FileSize;
if ((fstat(fileno(F),&S)==-1)) error("failed fstat\n"); // Need file size
FileSize = S.st_size;
char Response[BIG_ENUF];int HeaderCount=0;
HeaderCount=0;//Use to know where to fill buffer with sprintf
HeaderCount+=sprintf( Response+HeaderCount,"HTTP/1.0 200 OK\r\n");
HeaderCount+=sprintf( Response+HeaderCount,"Server: Flaky Server/1.0.0\r\n");
HeaderCount+=sprintf( Response+HeaderCount,"Content-Type: image/jpeg\r\n");
HeaderCount+=sprintf( Response+HeaderCount,"Content-Length:%d\r\n",FileSize);
//delimit header
HeaderCount+=sprintf( Response+HeaderCount,"\r\n");
fprintf(stderr,"HeaderCount %d and Header\n",HeaderCount);
write(STDERR_FILENO, Response, HeaderCount);
write(newsockfd,Response,HeaderCount); // and send to client
BigBuffer = malloc(FileSize+2);
fread(BigBuffer,1,FileSize,F);
write(newsockfd,BigBuffer,FileSize);
free(BigBuffer);
// Now close up this client
close(newsockfd);
return 0;
}
// bad error routine
void error(char *msg)
{
perror(msg);
exit(1);
}
I'm trying to convert these processes into a threads program. I'm very new to threads. But is the basic concept to move everything i have labeled under the child process to the thread function? and replace the forking with pthread_create s?
