6 files changed, 188 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..dab799c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,53 @@
+# Prerequisites
+*.d
+
+# Object files
+*.o
+*.ko
+*.obj
+*.elf
+
+# Linker output
+*.ilk
+*.map
+*.exp
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Libraries
+*.lib
+*.a
+*.la
+*.lo
+
+# Shared objects (inc. Windows DLLs)
+*.dll
+*.so
+*.so.*
+*.dylib
+
+# Executables
+*.exe
+*.out
+*.app
+*.i*86
+*.x86_64
+*.hex
+
+# Debug files
+*.dSYM/
+*.su
+*.idb
+*.pdb
+
+# Kernel Module Compile Results
+*.mod*
+*.cmd
+.tmp_versions/
+modules.order
+Module.symvers
+Mkfile.old
+dkms.conf
+
diff --git a/q1/client.c b/q1/client.c
new file mode 100644
index 0000000..a242e42
--- /dev/null
+++ b/q1/client.c
@@ -0,0 +1,42 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+
+int main(int argc, char *argv[]) { 
+    if (argc < 2) {
+        printf("Requires atleast 1 argument!\n");
+        return -1;
+    }
+    const char *server_name = "127.0.0.1";
+    int sockfd, connfd; 
+    struct sockaddr_in servaddr, cli; 
+
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    inet_pton(AF_INET, server_name, &servaddr.sin_addr);
+
+    int port = 0;
+    printf("Enter port to connect to: ");
+    scanf("%d", &port);
+    fflush(stdout);
+    fflush(stdin);
+    servaddr.sin_port = htons(port);
+
+    connect(sockfd, (struct sockaddr*)&servaddr, sizeof(servaddr));
+    printf("Connected to server!\n");
+    fflush(stdout);
+
+    char  file_contents[100];
+
+    send(sockfd, argv[1], strlen(argv[1]), 0);
+    int cont;
+    while((cont=(recv(sockfd, file_contents, 100, 0))) > 0) {
+        printf("File contents: %s", file_contents);
+    }
+    close(sockfd); 
+}
diff --git a/q1/makefile b/q1/makefile
new file mode 100644
index 0000000..e890624
--- /dev/null
+++ b/q1/makefile
@@ -0,0 +1,12 @@
+all: server.c client.c
+        gcc server.c -o server
+        gcc client.c -o client
+
+server: server.c
+        gcc server.c -o server
+
+client: client.c
+        gcc client.c -o client
+
+clean:
+        rm server client *.out
diff --git a/q1/server.c b/q1/server.c
new file mode 100644
index 0000000..92dfad6
--- /dev/null
+++ b/q1/server.c
@@ -0,0 +1,64 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <unistd.h>
+#include <string.h>
+#include <arpa/inet.h>
+
+int main() {
+    int sockfd, connfd; 
+    struct sockaddr_in servaddr, cli; 
+  
+    sockfd = socket(AF_INET, SOCK_STREAM, 0); 
+    servaddr.sin_family = AF_INET; 
+    servaddr.sin_addr.s_addr = htonl(INADDR_ANY); 
+
+    int port = 0;
+    printf("Enter port to bind to: ");
+    scanf("%d", &port);
+    fflush(stdout);
+    fflush(stdin);
+
+    servaddr.sin_port = htons(port);
+  
+    bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
+  
+    listen(sockfd, 128);
+    socklen_t len = sizeof(cli);
+    printf("Server started at %s...\n", inet_ntoa(servaddr.sin_addr));
+    fflush(stdout);
+
+    connfd = accept(sockfd, (struct sockaddr *)&cli, &len);
+    if (connfd < 0) {
+        printf("Couldn't open socket!\n");
+        close(sockfd);
+        return -1;
+    }
+
+    printf("Client connected with IP address: %s\n", inet_ntoa(cli.sin_addr));
+    fflush(stdout);
+
+    char filename[100];
+    bzero(filename, 100);
+    int n;
+    n = recv(connfd, filename, 100, 0);
+    printf("received: '%s'", filename);
+    fflush(stdout);
+
+    FILE *request_file = fopen(filename, "r");
+    if (request_file == NULL) {
+        printf("File not found: %s", filename);
+        send(connfd, "file not found", 14, 0);
+    } else {
+        char file_contents[500];
+        while(fgets(file_contents, 100, request_file)) {
+            fflush(stdout);
+            send(connfd, file_contents, 100, 0);
+        };
+        fclose(request_file);
+    }
+    fflush(stdout);
+    close(sockfd);
+}
diff --git a/readme.txt b/readme.txt
new file mode 100644
index 0000000..62fd58d
--- /dev/null
+++ b/readme.txt
@@ -0,0 +1,9 @@
+Akshay's NPS lab programs
+-------------------------
+
+Q1: Write a networking program consisting of a client and
+server components. The client must request for a file by
+providing a file name, and the server must respond with the
+contents of the file or an appropriate error message. Bonus:
+Modify the client to accept the filname via a command line
+argument.
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..67483ce
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,8 @@
+{ pkgs ? import <nixpkgs> {} }:
+
+pkgs.mkShell {
+  buildInputs =  with pkgs; [
+    gcc
+    clang-tools
+  ];
+}