feat: add step to receive request body in buffer

Makefile

@@ -50,7 +50,7 @@ objs: $(OBJS)
 .PHONY: bin
 bin: $(BIN)
 $(BIN): $(OBJS)
-	$(CC) $(INTERNALCFLAGS) $(LDFLAGS) -o $@ $^
+	$(CC) $(INTERNALCFLAGS) $(LDFLAGS) -lm -o $@ $^
 
 $(BUILD_DIR)/$(SRC_DIR)/%.c.o: $(SRC_DIR)/%.c
 	mkdir -p $(dir $@)

include/http.h

@@ -35,8 +35,12 @@ typedef struct http_request {
   size_t path_len;
   const char *query;
   size_t query_len;
+  char *body;
+  size_t body_len;
+  size_t body_received;
   regmatch_t regex_groups[HTTP_MAX_REGEX_GROUPS];
   struct phr_header headers[HTTP_MAX_ALLOWED_HEADERS];
+  size_t num_headers;
 } http_request;
 
 typedef enum http_parse_error {

include/http_loop.h

@@ -7,6 +7,9 @@
 #include "http.h"
 #include "trie.h"
 
+#define MIN(x, y) (((x) < (y)) ? (x) : (y))
+#define MAX(x, y) (((x) > (y)) ? (x) : (y))
+
 typedef enum http_route_type {
   http_route_literal = 0,
   http_route_regex = 1,
@@ -102,6 +105,11 @@ void http_loop_res_set_body_file(http_loop_ctx *ctx, const char *filename);
 void http_loop_res_add_header(http_loop_ctx *ctx, http_header type,
                               const char *value, bool owned);
 
+/*
+ * Request step that consumes the request body and stores it in a buffer
+ */
+bool http_loop_step_body_to_buf(event_loop_conn *conn);
+
 /**
  * Initialize a new http loop
  */

include/lander.h

@@ -3,6 +3,8 @@
 
 #include "http_loop.h"
 
-extern http_route lander_routes[2];
+extern http_route lander_routes[3];
+
+bool lander_post_redirect(event_loop_conn *conn);
 
 #endif

src/http_loop/http_loop_ctx.c

@@ -26,6 +26,11 @@ void http_loop_ctx_reset(http_loop_ctx *ctx) {
   ctx->route = NULL;
   ctx->current_step = 0;
 
+  if (ctx->req.body != NULL) {
+    free((void *)ctx->req.body);
+    ctx->req.body = NULL;
+  }
+
   if (ctx->res.head != NULL) {
     free((void *)ctx->res.head);
     ctx->res.head = NULL;

src/http_loop/http_loop_req.c

@@ -27,6 +27,7 @@ http_parse_error http_loop_parse_request(event_loop_conn *conn) {
     return http_parse_error_incomplete;
   }
 
+  req->num_headers = num_headers;
   req->len = res;
 
   // Try to parse the method type

src/http_loop/http_loop_res.c

@@ -1,8 +1,6 @@
 #include "http_loop.h"
 #include "log.h"
 
-#define MIN(x, y) (((x) < (y)) ? (x) : (y))
-
 static const char *http_response_format = "HTTP/1.1 %i %s\n"
                                           "Server: lander/" LANDER_VERSION "\n"
                                           "Content-Length: %lu\n";

src/http_loop/http_loop_tools.c

@@ -1,3 +1,4 @@
+#include <math.h>
 #include <stdio.h>
 #include <sys/stat.h>
 
@@ -31,3 +32,68 @@ void http_loop_res_add_header(http_loop_ctx *ctx, http_header type,
 
   ctx->res.header_count++;
 }
+
+/*
+ * Converts a string to a number, returning true if the string contained a valid
+ * positive number.
+ */
+static bool string_to_num(size_t *res, const char *s, size_t len) {
+  *res = 0;
+
+  for (size_t i = 0; i < len; i++) {
+    int val = s[i] - '0';
+
+    if (val < 0 || val > 9) {
+      return false;
+    }
+
+    *res += val * (int)pow(10, (len - 1) - i);
+  }
+
+  return true;
+}
+
+bool http_loop_step_body_to_buf(event_loop_conn *conn) {
+  http_loop_ctx *ctx = conn->ctx;
+
+  if (ctx->req.body_len == 0) {
+    for (size_t i = 0; i < ctx->req.num_headers; i++) {
+      struct phr_header *header = &ctx->req.headers[i];
+
+      if (strncmp(header->name, "Content-Length", header->name_len) == 0) {
+        // If the content length header is present but contains an invalid
+        // number, we return a bad request error
+        if (!string_to_num(&ctx->req.body_len, header->value,
+                           header->value_len)) {
+          ctx->res.status = http_bad_request;
+          conn->state = event_loop_conn_state_res;
+
+          return true;
+        }
+        // The content length was actually 0, so we can instantly return here
+        else if (ctx->req.body_len == 0) {
+          return true;
+        }
+      }
+    }
+
+    // A zero here means there's no content length header
+    if (ctx->req.body_len == 0) {
+      ctx->res.status = http_length_required;
+      conn->state = event_loop_conn_state_res;
+
+      return true;
+    }
+
+    ctx->req.body = malloc(ctx->req.body_len * sizeof(uint8_t));
+    ctx->req.body_received = 0;
+  }
+
+  size_t bytes_to_copy = MIN(conn->rbuf_size - conn->rbuf_read,
+                             ctx->req.body_len - ctx->req.body_received);
+  memcpy(&ctx->req.body[ctx->req.body_received], &conn->rbuf[conn->rbuf_read],
+         bytes_to_copy);
+  ctx->req.body_received += bytes_to_copy;
+
+  return ctx->req.body_received == ctx->req.body_len;
+}

src/lander/lander.c

@@ -47,11 +47,16 @@ bool lander_get_entry(event_loop_conn *conn) {
   return true;
 }
 
-http_route lander_routes[] = {{.type = http_route_literal,
+http_route lander_routes[] = {
+    {.type = http_route_literal,
      .method = http_get,
      .path = "/",
      .steps = {lander_get_index, NULL}},
     {.type = http_route_regex,
      .method = http_get,
      .path = "^/\\([^/]\\+\\)$",
-                               .steps = {lander_get_entry, NULL}}};
+     .steps = {lander_get_entry, NULL}},
+    {.type = http_route_literal,
+     .method = http_post,
+     .path = "/s/",
+     .steps = {http_loop_step_body_to_buf, lander_post_redirect, NULL}}};

src/lander/lander_post.c

@@ -0,0 +1,12 @@
+#include "lander.h"
+#include "log.h"
+
+bool lander_post_redirect(event_loop_conn *conn) {
+  http_loop_ctx *ctx = conn->ctx;
+
+  info("%.*s", ctx->req.body_len, ctx->req.body);
+
+  conn->state = event_loop_conn_state_res;
+
+  return true;
+}