add http parser

backend/main.c

@@ -3,9 +3,46 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 #include <sys/socket.h>
 #include <unistd.h>
 
+typedef enum {
+    HttpMethodGet,
+    HttpMethodPost,
+} HttpMethod;
+
+typedef struct {
+    HttpMethod method;
+    size_t path_index, path_length;
+    size_t content_length;
+} HttpRequestHeader;
+
+HttpRequestHeader parse_http_request_header(const char* message, size_t message_size)
+{
+    size_t i = 0;
+
+    // parse method
+    HttpMethod method;
+    if (i + 3 < message_size && strncmp(&message[0], "GET", 3)) {
+        method = HttpMethodGet;
+        i += 3;
+    } else if (i + 4 < message_size && strncmp(&message[0], "POST", 4)) {
+        method = HttpMethodPost;
+        i += 4;
+    } else {
+        printf("error: header parse fail #1\n");
+        exit(1);
+    }
+
+    // skip space
+    i += 1;
+    if (i >= message_size) { }
+
+    return (HttpRequestHeader) { 0 };
+}
+
 const uint16_t port = 8000;
 
 int main(void)

backend/utils.h

@@ -0,0 +1,4 @@
+#ifndef UTILS_H
+#define UTILS_H
+
+#endif