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
diff --git a/aos/atom_code/output/HTTPServer.h b/aos/atom_code/output/HTTPServer.h
new file mode 100644
index 0000000..99eb295
--- /dev/null
+++ b/aos/atom_code/output/HTTPServer.h
@@ -0,0 +1,58 @@
+#include "event2/buffer.h"
+#include "event2/http.h"
+
+#include <string>
+
+namespace aos {
+namespace http {
+
+// An HTTP server that serves files from a directory using libevent.
+// Also allows configuring certain URLs to be dynamically generated.
+class HTTPServer {
+ public:
+  HTTPServer(const char *directory, uint16_t port);
+  // Starts serving pages.
+  // Might not clean up everything before returning.
+  void Run();
+ protected:
+  template<class T> class MemberHandler {
+   public:
+    typedef void (T::*Handler)(evhttp_request *);
+    struct Holder {
+      T *self;
+      Handler handler;
+    };
+    static void Call(evhttp_request *request, void *handler_in) {
+      const Holder *const holder = static_cast<Holder *>(handler_in);
+      AddStandardHeaders(request);
+      ((holder->self)->*(holder->handler))(request);
+    }
+  };
+  void AddPage(const std::string &path, void (*handler)(evhttp_request *, void *),
+               void *data);
+  template<class T> void AddPage(const std::string &path,
+                                 typename MemberHandler<T>::Handler handler,
+                                 T *self) {
+    // have to put "typename" in, so the typedef makes it clearer
+    typedef typename MemberHandler<T>::Holder HolderType;
+    AddPage(path, MemberHandler<T>::Call, new HolderType{self, handler});
+  }
+  // This gets set up as the generic handler.
+  // It can also be called separately to serve the file that the request is
+  // requesting from the filesystem.
+  void ServeFile(evhttp_request *request);
+ private:
+  // The directory where files to be served come from.
+  const char *directory_;
+  // The main libevent structure.
+  event_base *const base_;
+  // The libevent HTTP server handle.
+  evhttp *const http_;
+  static void AddStandardHeaders(evhttp_request *request);
+  static void StaticServeFile(evhttp_request *request, void *self) {
+    static_cast<HTTPServer *>(self)->ServeFile(request);
+  }
+};
+
+}  // namespace http
+}  // namespace aos
diff --git a/aos/atom_code/output/MotorOutput.cpp b/aos/atom_code/output/MotorOutput.cpp
new file mode 100644
index 0000000..ecbdf8b
--- /dev/null
+++ b/aos/atom_code/output/MotorOutput.cpp
@@ -0,0 +1,78 @@
+#include "aos/atom_code/output/MotorOutput.h"
+
+#include <math.h>
+
+#include "aos/common/Configuration.h"
+#include "aos/aos_core.h"
+#include "aos/common/byteorder.h"
+#include "aos/common/control_loop/Timing.h"
+#include "aos/atom_code/messages/DriverStationDisplay.h"
+
+namespace aos {
+
+MotorOutput::MotorOutput() : sock(NetworkPort::kMotors,
+          configuration::GetIPAddress(configuration::NetworkDevice::kCRIO)) {}
+
+void MotorOutput::Run() {
+  while (true) {
+    time::PhasedLoopXMS(5, 1000);
+    RunIteration();
+
+    // doesn't matter if multiple instances end up running this loop at the same
+    // time because the queue handles the race conditions
+    while (true) {
+      const aos::DriverStationDisplay *line = aos::DriverStationDisplay::GetNext();
+      if (line != NULL) {
+        AddDSLine(line->line, line->data);
+        LOG(DEBUG, "got a line %hhd that said '%s'\n", line->line, line->data);
+        aos::DriverStationDisplay::Free(line);
+      } else {
+        break;
+      }
+    }
+
+    if (sock.SendHoldMsg() == -1) {
+      LOG(WARNING, "sending outputs failed\n");
+      continue;
+    } else {
+      LOG(DEBUG, "sent outputs\n");
+    }
+  }
+}
+
+int MotorOutput::AddMotor(char type, uint8_t num, float value) {
+  if (sock.hold_msg_len_ + 4 > sock.MAX_MSG) {
+    return -1;
+  }
+  sock.hold_msg_[sock.hold_msg_len_ ++] = type;
+  sock.hold_msg_[sock.hold_msg_len_ ++] = num;
+  to_network(&value, &sock.hold_msg_[sock.hold_msg_len_]);
+  sock.hold_msg_len_ += 4;
+  return 0;
+}
+int MotorOutput::AddSolenoid(uint8_t port, bool on) {
+  if (sock.hold_msg_len_ + 3 > sock.MAX_MSG) {
+    return -1;
+  }
+  sock.hold_msg_[sock.hold_msg_len_ ++] = 's';
+  sock.hold_msg_[sock.hold_msg_len_ ++] = port;
+  sock.hold_msg_[sock.hold_msg_len_ ++] = on ? 1 : 0;
+  return 0;
+}
+
+int MotorOutput::AddDSLine(uint8_t line, const char *data) {
+  size_t data_len = strlen(data); // doesn't include terminating NULL
+  if (sock.hold_msg_len_ + 3 + data_len > sock.MAX_MSG) {
+    return -1;
+  }
+
+  sock.hold_msg_[sock.hold_msg_len_ ++] = 'd';
+  sock.hold_msg_[sock.hold_msg_len_ ++] = line;
+  sock.hold_msg_[sock.hold_msg_len_ ++] = data_len;
+  memcpy(&sock.hold_msg_[sock.hold_msg_len_], data, data_len);
+  sock.hold_msg_len_ += data_len;
+  return 0;
+}
+
+} // namespace aos
+
diff --git a/aos/atom_code/output/MotorOutput.h b/aos/atom_code/output/MotorOutput.h
new file mode 100644
index 0000000..925139a
--- /dev/null
+++ b/aos/atom_code/output/MotorOutput.h
@@ -0,0 +1,74 @@
+#ifndef AOS_ATOM_CODE_OUTPUT_MOTOR_OUTPUT_H_
+#define AOS_ATOM_CODE_OUTPUT_MOTOR_OUTPUT_H_
+
+#include <stdint.h>
+#include <string.h>
+#include <algorithm>
+#include <string>
+
+#include "aos/common/network/SendSocket.h"
+#include "aos/common/byteorder.h"
+#include "aos/common/type_traits.h"
+
+namespace aos {
+
+class MotorOutput {
+ public:
+  MotorOutput();
+  void Run();
+
+  // Constants for the first argument of AddMotor.
+  static const char VICTOR = 'v';
+  static const char TALON = 't';
+
+ protected:
+  // num is 1-indexed
+  int AddMotor(char type, uint8_t num, float value);
+  int AddSolenoid(uint8_t num, bool on);
+  int AddDSLine(uint8_t line, const char *data);
+  // loop_queuegroup is expected to be a control loop queue group.
+  // This function will fetch the latest goal and serve it.
+  template <class T>
+  int AddControlLoopGoal(T *loop_queuegroup);
+
+  virtual void RunIteration() = 0;
+
+ private:
+  SendSocket sock;
+};
+
+template <class T>
+int MotorOutput::AddControlLoopGoal(T *loop_queuegroup) {
+  typedef typename std::remove_reference<
+      decltype(*(loop_queuegroup->goal.MakeMessage().get()))>::type GoalType;
+  // TODO(aschuh): This assumes a static serialized message size.
+  const uint16_t size = GoalType::Size();
+  if (sock.hold_msg_len_ + 4 + 1 + size > sock.MAX_MSG) {
+    return -1;
+  }
+
+  const bool zero = !loop_queuegroup->goal.FetchLatest();
+
+  sock.hold_msg_[sock.hold_msg_len_ ++] = 'g';
+  const uint32_t hash = loop_queuegroup->hash();
+
+  // Place the loop hash at the front.
+  to_network(&hash, &sock.hold_msg_[sock.hold_msg_len_]);
+  sock.hold_msg_len_ += 4;
+
+  if (zero) {
+    GoalType zero_message;
+    zero_message.Zero();
+    zero_message.Serialize(&sock.hold_msg_[sock.hold_msg_len_]);
+    sock.hold_msg_len_ += size;
+    return -1;
+  } else {
+    loop_queuegroup->goal->Serialize(&sock.hold_msg_[sock.hold_msg_len_]);
+    sock.hold_msg_len_ += size;
+    return 0;
+  }
+}
+
+}  // namespace aos
+
+#endif
diff --git a/aos/atom_code/output/evhttp_ctemplate_emitter.cc b/aos/atom_code/output/evhttp_ctemplate_emitter.cc
new file mode 100644
index 0000000..ed2a83f
--- /dev/null
+++ b/aos/atom_code/output/evhttp_ctemplate_emitter.cc
@@ -0,0 +1,18 @@
+#include "aos/atom_code/output/evhttp_ctemplate_emitter.h"
+
+#include "aos/aos_core.h"
+
+namespace aos {
+namespace http {
+
+void EvhttpCtemplateEmitter::Emit(const char *s, size_t slen) {
+  if (error_) return;
+  if (evbuffer_add(buf_, s, slen) != 0) {
+    LOG(ERROR, "evbuffer_add(%p, %p, %zd) failed\n",
+        buf_, s, slen);
+    error_ = true;
+  }
+}
+
+}  // namespace http
+}  // namespace aos
diff --git a/aos/atom_code/output/evhttp_ctemplate_emitter.h b/aos/atom_code/output/evhttp_ctemplate_emitter.h
new file mode 100644
index 0000000..d20d2cb
--- /dev/null
+++ b/aos/atom_code/output/evhttp_ctemplate_emitter.h
@@ -0,0 +1,34 @@
+#ifndef AOS_ATOM_CODE_OUTPUT_EVHTTP_CTEMPLATE_EMITTER_H_
+#define AOS_ATOM_CODE_OUTPUT_EVHTTP_CTEMPLATE_EMITTER_H_
+
+#include <string.h>
+
+#include "event2/buffer.h"
+#include "ctemplate/template_emitter.h"
+
+namespace aos {
+namespace http {
+
+// Writes everything directly into an evbuffer*.
+// Handles errors by refusing to write anything else into the buffer and storing
+// the state (which can be retrieved with error()).
+class EvhttpCtemplateEmitter : public ctemplate::ExpandEmitter {
+ public:
+  EvhttpCtemplateEmitter(evbuffer *buf) : buf_(buf), error_(false) {}
+  virtual void Emit(char c) { Emit(&c, 1); };
+  virtual void Emit(const std::string& s) { Emit(s.data(), s.size()); };
+  virtual void Emit(const char* s) { Emit(s, strlen(s)); }
+  virtual void Emit(const char* s, size_t slen);
+  // Retrieves whether or not there has been an error. If true, the error will
+  // already have been logged.
+  bool error() { return error_; }
+
+ private:
+  evbuffer *const buf_;
+  bool error_;
+};
+
+}  // namespace http
+}  // namespace aos
+
+#endif  // AOS_ATOM_CODE_OUTPUT_EVHTTP_CTEMPLATE_EMITTER_H_
diff --git a/aos/atom_code/output/output.gyp b/aos/atom_code/output/output.gyp
new file mode 100644
index 0000000..3e4abd4
--- /dev/null
+++ b/aos/atom_code/output/output.gyp
@@ -0,0 +1,35 @@
+{
+  'targets': [
+    {
+      'target_name': 'http_server',
+      'type': 'static_library',
+      'sources': [
+        'HTTPServer.cpp',
+        'evhttp_ctemplate_emitter.cc',
+      ],
+      'dependencies': [
+        '<(AOS)/build/aos.gyp:libaos',
+        '<(EXTERNALS):libevent',
+        '<(EXTERNALS):ctemplate',
+      ],
+      'export_dependent_settings': [
+# Our headers #include headers from both of these.
+        '<(EXTERNALS):libevent',
+        '<(EXTERNALS):ctemplate',
+      ],
+    },
+    {
+      'target_name': 'motor_output',
+      'type': 'static_library',
+      'sources': [
+        'MotorOutput.cpp',
+      ],
+      'dependencies': [
+        '<(AOS)/build/aos.gyp:libaos',
+      ],
+      'export_dependent_settings': [
+        '<(AOS)/build/aos.gyp:libaos',
+      ],
+    },
+  ],
+}