copied everything over from 2012 and removed all of the actual robot code except the drivetrain stuff


git-svn-id: https://robotics.mvla.net/svn/frc971/2013/trunk/src@4078 f308d9b7-e957-4cde-b6ac-9a88185e7312
diff --git a/aos/atom_code/output/HTTPServer.cpp b/aos/atom_code/output/HTTPServer.cpp
new file mode 100644
index 0000000..88e3c6f
--- /dev/null
+++ b/aos/atom_code/output/HTTPServer.cpp
@@ -0,0 +1,153 @@
+#include "aos/atom_code/output/HTTPServer.h"
+
+#include <inttypes.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include <memory>
+
+#include "event2/event.h"
+
+#include "aos/aos_core.h"
+#include "aos/common/scoped_fd.h"
+#include "aos/common/unique_malloc_ptr.h"
+
+namespace aos {
+namespace http {
+
+HTTPServer::HTTPServer(const char *directory, uint16_t port) :
+    directory_(directory), base_(event_base_new()), http_(evhttp_new(base_)) {
+  if (base_ == NULL) {
+    LOG(FATAL, "couldn't create an event_base\n");
+  }
+  if (http_ == NULL) {
+    LOG(FATAL, "couldn't create an evhttp\n");
+  }
+  if (evhttp_bind_socket(http_, "0.0.0.0", port) != 0) {
+    LOG(FATAL, "evhttp_bind_socket(%p, \"0.0.0.0\", %"PRIu16") failed\n",
+        http_, port);
+  }
+  evhttp_set_gencb(http_, StaticServeFile, this);
+}
+
+void HTTPServer::AddPage(const std::string &path,
+                         void (*handler)(evhttp_request *, void *), void *data) {
+  switch (evhttp_set_cb(http_, path.c_str(), handler, data)) {
+    case 0:
+      LOG(DEBUG, "set callback handler for '%s'\n", path.c_str());
+      break;
+    case -1:
+      LOG(INFO, "changed callback handler for '%s'\n", path.c_str());
+      break;
+    default:
+      LOG(WARNING, "evhttp_set_cb(%p, %s, %p, %p) failed\n", http_, path.c_str(),
+          handler, data);
+      break;
+  }
+}
+
+void HTTPServer::AddStandardHeaders(evhttp_request *request) {
+  if (evhttp_add_header(evhttp_request_get_output_headers(request),
+                        "Server", "aos::HTTPServer/0.0") == -1) {
+    LOG(WARNING, "adding Server header failed\n");
+  }
+}
+
+namespace {
+// All of these functions return false, NULL, or -1 if they fail (and send back
+// an error).
+
+// Returns the path of the file that is being requested.
+const char *GetPath(evhttp_request *request) {
+  // Docs are unclear whether this needs freeing, but it looks like it just
+  // returns an internal field of the request.
+  // Running valgrind with no freeing of uri or path doesn't report anything
+  // related to this code.
+  const evhttp_uri *uri = evhttp_request_get_evhttp_uri(request);
+  const char *path = evhttp_uri_get_path(uri);
+  if (path == NULL) {
+    evhttp_send_error(request, HTTP_BADREQUEST, "need a path");
+    return NULL;
+  }
+  if (strstr(path, "..") != NULL) {
+    evhttp_send_error(request, HTTP_NOTFOUND, "no .. allowed!!");
+    return NULL;
+  }
+  return path;
+}
+// Returns an fd open for reading for the file at "directory/path".
+int OpenFile(evhttp_request *request, const char *path,
+                   const char *directory) {
+  char *temp;
+  if (asprintf(&temp, "%s/%s", directory, path) == -1) {
+    LOG(WARNING, "asprintf(%p, \"%%s/%%s\", %p, %p) failed with %d: %s\n",
+        &temp, directory, path, errno, strerror(errno));
+    evhttp_send_error(request, HTTP_INTERNAL, NULL);
+    return -1;
+  }
+  const unique_c_ptr<char> filename(temp);
+  ScopedFD file(open(filename.get(), O_RDONLY));
+  if (!file) {
+    if (errno == ENOENT) {
+      evhttp_send_error(request, HTTP_NOTFOUND, NULL);
+      return -1;
+    }
+    LOG(ERROR, "open('%s', 0) failed with %d: %s\n", filename.get(),
+        errno, strerror(errno));
+    evhttp_send_error(request, HTTP_INTERNAL, NULL);
+    return -1;
+  }
+  return file.release();
+}
+// Returns the size of the file specified by the given fd.
+off_t GetSize(int file) {
+  struct stat info;
+  if (fstat(file, &info) == -1) {
+    LOG(ERROR, "stat(%d, %p) failed with %d: %s\n", file, &info,
+        errno, strerror(errno));
+    return -1;
+  }
+  return info.st_size;
+}
+bool SendFileResponse(evhttp_request *request, int file_num) {
+  ScopedFD file(file_num);
+  const off_t size = GetSize(file.get());
+  if (size == -1) {
+    evhttp_send_error(request, HTTP_INTERNAL, NULL);
+    return false;
+  }
+  evbuffer *const buf = evhttp_request_get_output_buffer(request);
+  if (evbuffer_add_file(buf, file.get(), 0, size) == -1) {
+    LOG(WARNING, "evbuffer_add_file(%p, %d, 0, %jd) failed\n", buf,
+        file.get(), static_cast<intmax_t>(size));
+    evhttp_send_error(request, HTTP_INTERNAL, NULL);
+    return false;
+  } else {
+    // it succeeded, so evhttp takes ownership
+    file.release();
+  }
+  evhttp_send_reply(request, HTTP_OK, NULL, NULL);
+  return true;
+}
+
+}  // namespace
+void HTTPServer::ServeFile(evhttp_request *request) {
+  AddStandardHeaders(request);
+
+  const char *path = GetPath(request);
+  if (path == NULL) return;
+
+  ScopedFD file(OpenFile(request, path, directory_));
+  if (!file) return;
+
+  if (!SendFileResponse(request, file.release())) return;
+}
+
+void HTTPServer::Run() {
+  event_base_dispatch(base_);
+  LOG(FATAL, "event_base_dispatch returned\n");
+}
+
+}  // namespace http
+}  // namespace aos