add request handler for http request and response generation

request_handler.c

@@ -0,0 +1,78 @@
+
+#include "request_handler.h"
+
+void handle_request(char* request, int length, char* response,
+                    size_t* response_length) {
+    request[length] = '\0';  // Null terminate request for printing
+
+    printf("Request ---------\n");
+    printf("%s\n---------\n", request);
+
+    // Check if request is GET
+    char* ptr = request;  // Modifiable pointer to request
+    char buf_temp[10];    // Temporary buffer to store request code
+    char* ptr_temp =
+        (char*)&buf_temp;  // Modifiable pointer to temporary buffer
+    // Copy request code to temporary buffer
+    while (*ptr != ' ') {
+        *ptr_temp = *ptr;
+        ptr++;
+        ptr_temp++;
+    }
+    // Null terminate temporary buffer
+    *ptr_temp = '\0';
+    ptr++;  // Skip over space
+    if (strcmp(buf_temp, "GET") == 0) {
+        printf("Received a GET request!!\n");
+    } else {
+        printf("Received a non-GET request!!\n");
+        return;
+    }
+
+    // Get filename from request url
+    char filename[100];           // Buffer to store filename
+    ptr_temp = (char*)&filename;  // Modifiable pointer to filename
+    *ptr_temp = '.';              // Prepend . to filename
+    ptr_temp++;
+    // While loop to copy filename to temporary buffer
+    while (*ptr != ' ') {
+        // Convert %20 to space
+        if (*ptr == '%' && *(ptr + 1) == '2' && *(ptr + 2) == '0') {
+            ptr += 3;
+            *ptr_temp = ' ';
+            ptr_temp++;
+        } else {
+            // Copy character
+            *ptr_temp = *ptr;
+            ptr++;
+            ptr_temp++;
+        }
+    }
+    *ptr_temp = '\0';  // Null terminate filename
+
+    // Print filename
+    printf("Filename: %s\n", filename);
+
+    // Create reponse string
+    ptr_temp = response;
+    char* temp = "HTTP/1.1 200 OK\nContent-Type: text/html\n\n";
+    while (*temp != '\0') {
+        *ptr_temp = *temp;
+        ptr_temp++;
+        temp++;
+    }
+    // Put the filename in the html response
+    temp = filename;
+    while (*temp != '\0') {
+        *ptr_temp = *temp;
+        ptr_temp++;
+        temp++;
+    }
+
+    *ptr_temp = '\0';  // Null terminate response
+
+    printf("Response --------\n");
+    printf("%s\n--------\n", response);
+
+    *response_length = strlen(response);
+}