better nl stuff, rename SIMPLE_THREADS_NO_IMPLICIT_YIELD

dtool/Config.pp

@@ -704,31 +704,32 @@
 // default is to use OS-provided threading constructs, which usually
 // allows for full multiprogramming support (i.e. the program can take
 // advantage of multiple CPU's).  On the other hand, compiling in this
-// full OS-provided support can impose some runtime overhead, making
-// the application run slower on a single-CPU machine.  To avoid this
-// overhead, but still gain some of the basic functionality of threads
-// (such as support for asynchronous model loads), define
-// SIMPLE_THREADS true in addition to HAVE_THREADS.  This will compile
-// in a homespun cooperative threading implementation that runs
-// strictly on one CPU, adding very little overhead over plain
-// single-threaded code.  
+// full OS-provided support can impose some substantial runtime
+// overhead, making the application run slower on a single-CPU
+// machine.  To avoid this overhead, but still gain some of the basic
+// functionality of threads (such as support for asynchronous model
+// loads), define SIMPLE_THREADS true in addition to HAVE_THREADS.
+// This will compile in a homespun cooperative threading
+// implementation that runs strictly on one CPU, adding very little
+// overhead over plain single-threaded code.
 
-// Enabling SIMPLE_THREADS is highly experimental at the present time.
 // Since SIMPLE_THREADS requires special support from the C runtime
 // library, it may not be available on all platforms and
-// architectures.
+// architectures.  (However, it is known to be available on the big
+// three: Linux, Win32, and OSX, with their most common
+// architectures.)
 #define SIMPLE_THREADS
 
-// If you are using SIMPLE_THREADS, the default is to consider an
-// implicit context switch at every attempt to lock a mutex.  This
-// makes it less necessary to pepper your code with explicit calls to
-// Thread::consider_yield().  However, you may want to restrict this
-// behavior, and only allow context switches at explicit calls to
-// Thread::yield(), consider_yield(), and sleep() (as well as calls to
-// ConditionVar::wait()).  This gives you absolute control over when
-// the context switch happens, and makes mutexes unnecessary (mutexes
-// will be compiled out).  Define this true to build that way.
-#define SIMPLE_THREADS_NO_IMPLICIT_YIELD
+// If you are using SIMPLE_THREADS, you might further wish to disable
+// mutexes altogether.  In this mode, mutexes are compiled out (they
+// become a no-op), and the only context switches happen at explicit
+// calls to Thread::force_yield(), consider_yield(), and sleep(), as
+// well as calls to ConditionVar::wait(), and certain I/O operations.
+// This gives you control over when the context switch happens, and
+// may make mutexes unnecessary, if you are somewhat careful in your
+// code design.  Disabling mutexes saves a tiny bit of runtime and
+// memory overhead.
+#define SIMPLE_THREADS_NO_MUTEX
 
 // Whether threading is defined or not, you might want to validate the
 // thread and synchronization operations.  With threading enabled,
@@ -746,6 +747,15 @@
 // than CPU's.  Even then, OS-based locking is probably better.
 #define MUTEX_SPINLOCK
 
+// Define this to use the PandaFileStream interface for pifstream,
+// pofstream, and pfstream.  This is a customized file buffer that may
+// have slightly better newline handling, but its primary benefit is
+// that it supports SIMPLE_THREADS better by blocking just the active
+// "thread" when I/O is delayed, instead of blocking the entire
+// process.  Normally, there's no reason to turn this off, unless you
+// suspect a bug in Panda.
+#define USE_PANDAFILESTREAM
+
 // Do you want to build the PStats interface, for graphical run-time
 // performance statistics?  This requires NET to be available.  By
 // default, we don't build PStats when OPTIMIZE = 4, although this is

dtool/LocalSetup.pp

@@ -310,7 +310,7 @@ $[cdefine HAVE_THREADS]
 
 /* Define if we want to use fast, user-space simulated threads.  */
 $[cdefine SIMPLE_THREADS]
-$[cdefine SIMPLE_THREADS_NO_IMPLICIT_YIELD]
+$[cdefine SIMPLE_THREADS_NO_MUTEX]
 
 /* Define to enable deadlock detection, mutex recursion checks, etc. */
 $[cdefine DEBUG_THREADS]
@@ -318,6 +318,9 @@ $[cdefine DEBUG_THREADS]
 /* Define to implement mutexes and condition variables via a user-space spinlock. */
 $[cdefine MUTEX_SPINLOCK]
 
+/* Define to enable the PandaFileStream implementation of pfstream etc. */
+$[cdefine USE_PANDAFILESTREAM]
+
 /* Define if we want to compile the net code.  */
 $[cdefine HAVE_NET]
 

dtool/src/dtoolutil/filename.cxx

@@ -1913,7 +1913,7 @@ open_read_write(fstream &stream) const {
   return (!stream.fail());
 }
 
-/*
+#ifdef USE_PANDAFILESTREAM
 ////////////////////////////////////////////////////////////////////
 //     Function: Filename::open_read
 //       Access: Published
@@ -1945,7 +1945,9 @@ open_read(pifstream &stream) const {
   stream.open(os_specific.c_str(), open_mode);
   return (!stream.fail());
 }
+#endif  // USE_PANDAFILESTREAM
 
+#ifdef USE_PANDAFILESTREAM
 ////////////////////////////////////////////////////////////////////
 //     Function: Filename::open_write
 //       Access: Published
@@ -2000,7 +2002,9 @@ open_write(pofstream &stream, bool truncate) const {
 
   return (!stream.fail());
 }
+#endif  // USE_PANDAFILESTREAM
 
+#ifdef USE_PANDAFILESTREAM
 ////////////////////////////////////////////////////////////////////
 //     Function: Filename::open_append
 //       Access: Published
@@ -2037,7 +2041,9 @@ open_append(pofstream &stream) const {
 
   return (!stream.fail());
 }
+#endif  // USE_PANDAFILESTREAM
 
+#ifdef USE_PANDAFILESTREAM
 ////////////////////////////////////////////////////////////////////
 //     Function: Filename::open_read_write
 //       Access: Published
@@ -2080,7 +2086,7 @@ open_read_write(pfstream &stream) const {
 
   return (!stream.fail());
 }
-*/
+#endif  // USE_PANDAFILESTREAM
 
 ////////////////////////////////////////////////////////////////////
 //     Function: Filename::touch

dtool/src/dtoolutil/filename.h

@@ -180,12 +180,12 @@ PUBLISHED:
   bool open_append(ofstream &stream) const;
   bool open_read_write(fstream &stream) const;
 
-  /*
+#ifdef USE_PANDAFILESTREAM
   bool open_read(pifstream &stream) const;
   bool open_write(pofstream &stream, bool truncate = true) const;
   bool open_append(pofstream &stream) const;
   bool open_read_write(pfstream &stream) const;
-  */
+#endif  // USE_PANDAFILESTREAM
 
   bool chdir() const;
   bool touch() const;

dtool/src/dtoolutil/pandaFileStream.cxx

@@ -14,4 +14,8 @@
 
 #include "pandaFileStream.h"
 
+#ifdef USE_PANDAFILESTREAM
+
+
+#endif   // USE_PANDAFILESTREAM
 

dtool/src/dtoolutil/pandaFileStream.h

@@ -16,6 +16,9 @@
 #define PANDAFILESTREAM_H
 
 #include "dtoolbase.h"
+
+#ifdef USE_PANDAFILESTREAM
+
 #include "pandaFileStreamBuf.h"
 
 ////////////////////////////////////////////////////////////////////
@@ -86,15 +89,16 @@ private:
 
 #include "pandaFileStream.I"
 
-// Not ready for prime time yet.
-/*
 typedef IFileStream pifstream;
 typedef OFileStream pofstream;
 typedef FileStream pfstream;
-*/
+
+#else   // USE_PANDAFILESTREAM
 
 typedef ifstream pifstream;
 typedef ofstream pofstream;
 typedef fstream pfstream;
 
+#endif  // USE_PANDAFILESTREAM
+
 #endif

dtool/src/dtoolutil/pandaFileStreamBuf.cxx

@@ -15,6 +15,8 @@
 #include "pandaFileStreamBuf.h"
 #include "memoryHook.h"
 
+#ifdef USE_PANDAFILESTREAM
+
 #ifndef _WIN32
 #include <sys/types.h>
 #include <sys/stat.h>
@@ -22,6 +24,8 @@
 #include <errno.h>
 #endif  // _WIN32
 
+PandaFileStreamBuf::NewlineMode PandaFileStreamBuf::_newline_mode = NM_native;
+
 static const size_t file_buffer_size = 4096;
 
 ////////////////////////////////////////////////////////////////////
@@ -507,17 +511,43 @@ write_chars(const char *start, size_t length) {
   // The file is opened in text mode.  We have to encode newline
   // characters to the file.
 
+  NewlineMode this_newline_mode = _newline_mode;
+  if (this_newline_mode == NM_native) {
 #ifdef _WIN32
-  // Windows requires a larger buffer here, since we are writing two
-  // newline characters for every one.
-  size_t buffer_length = length * 2;
+    this_newline_mode = NM_msdos;
 #else
-  size_t buffer_length = length;
-#endif  // _WIN32
+    // Even the Mac uses Unix-style EOL characters these days.
+    this_newline_mode = NM_unix;
+#endif 
+  }
 
+  if (this_newline_mode == NM_binary) {
+    return write_chars_raw(start, length);
+  }
+
+  size_t buffer_length = length;
+  if (this_newline_mode == NM_msdos) {
+    // Windows requires a larger buffer here, since we are writing two
+    // newline characters for every one.
+    buffer_length *= 2;
+  }
   char *buffer = (char *)alloca(buffer_length);
 
-  size_t write_length = encode_newlines(buffer, buffer_length, start, length);
+  size_t write_length;
+  switch (this_newline_mode) {
+  case NM_msdos:
+    write_length = encode_newlines_msdos(buffer, buffer_length, start, length);
+    break;
+
+  case NM_mac:
+    write_length = encode_newlines_mac(buffer, buffer_length, start, length);
+    break;
+
+  default:
+    write_length = encode_newlines_unix(buffer, buffer_length, start, length);
+    break;
+  }
+
   if (write_length == write_chars_raw(buffer, write_length)) {
     // Success.  Return the number of original characters.
     return length;
@@ -770,10 +800,8 @@ decode_newlines(char *dest, size_t dest_length,
   return q - dest;
 }
 
-#ifdef _WIN32
-
 ////////////////////////////////////////////////////////////////////
-//     Function: PandaFileStreamBuf::encode_newlines
+//     Function: PandaFileStreamBuf::encode_newlines_msdos
 //       Access: Private
 //  Description: Windows case: Converts a buffer from \n to \n\r.
 //
@@ -783,8 +811,8 @@ decode_newlines(char *dest, size_t dest_length,
 //               Returns the number of characters placed in dest.
 ////////////////////////////////////////////////////////////////////
 size_t PandaFileStreamBuf::
-encode_newlines(char *dest, size_t dest_length,
-                const char *source, size_t source_length) {
+encode_newlines_msdos(char *dest, size_t dest_length,
+                      const char *source, size_t source_length) {
   const char *p = source;  // Read from p
   char *q = dest;          // Write to q
 
@@ -812,12 +840,10 @@ encode_newlines(char *dest, size_t dest_length,
   return q - dest;
 }
 
-#else  // _WIN32
-
 ////////////////////////////////////////////////////////////////////
-//     Function: PandaFileStreamBuf::encode_newlines
+//     Function: PandaFileStreamBuf::encode_newlines_unix
 //       Access: Private
-//  Description: Posix case: Converts a buffer from \n to \n.
+//  Description: Unix case: Converts a buffer from \n to \n.
 //
 //               This is, of course, no conversion at all; but we do
 //               strip out \r characters if they appear in the buffer;
@@ -828,8 +854,8 @@ encode_newlines(char *dest, size_t dest_length,
 //               Returns the number of characters placed in dest.
 ////////////////////////////////////////////////////////////////////
 size_t PandaFileStreamBuf::
-encode_newlines(char *dest, size_t dest_length,
-                const char *source, size_t source_length) {
+encode_newlines_unix(char *dest, size_t dest_length,
+                     const char *source, size_t source_length) {
   const char *p = source;  // Read from p
   char *q = dest;          // Write to q
 
@@ -850,4 +876,86 @@ encode_newlines(char *dest, size_t dest_length,
   return q - dest;
 }
 
-#endif  // _WIN32
+////////////////////////////////////////////////////////////////////
+//     Function: PandaFileStreamBuf::encode_newlines_mac
+//       Access: Private
+//  Description: Classic Mac case: Converts a buffer from \n to \r.
+//
+//               Returns the number of characters placed in dest.
+////////////////////////////////////////////////////////////////////
+size_t PandaFileStreamBuf::
+encode_newlines_mac(char *dest, size_t dest_length,
+                    const char *source, size_t source_length) {
+  const char *p = source;  // Read from p
+  char *q = dest;          // Write to q
+
+  while (p < source + source_length) {
+    assert(q < dest + dest_length);
+    switch (*p) {
+    case '\n':
+      *q++ = '\r';
+      break;
+
+    case '\r':
+      break;
+
+    default:
+      *q++ = *p;
+      break;
+    }
+
+    ++p;
+  }
+
+  return q - dest;
+}
+
+ostream &
+operator << (ostream &out, PandaFileStreamBuf::NewlineMode newline_mode) {
+  switch (newline_mode) {
+  case PandaFileStreamBuf::NM_native:
+    return out << "native";
+
+  case PandaFileStreamBuf::NM_binary:
+    return out << "binary";
+
+  case PandaFileStreamBuf::NM_msdos:
+    return out << "msdos";
+
+  case PandaFileStreamBuf::NM_unix:
+    return out << "unix";
+
+  case PandaFileStreamBuf::NM_mac:
+    return out << "mac";
+  }
+
+  cerr
+    << "Invalid NewlineMode value: " << (int)newline_mode << "\n";
+  return out;
+}
+
+istream &
+operator >> (istream &in, PandaFileStreamBuf::NewlineMode &newline_mode) {
+  string word;
+  in >> word;
+
+  if (word == "native") {
+    newline_mode = PandaFileStreamBuf::NM_native;
+  } else if (word == "binary") {
+    newline_mode = PandaFileStreamBuf::NM_binary;
+  } else if (word == "msdos") {
+    newline_mode = PandaFileStreamBuf::NM_msdos;
+  } else if (word == "unix") {
+    newline_mode = PandaFileStreamBuf::NM_unix;
+  } else if (word == "mac") {
+    newline_mode = PandaFileStreamBuf::NM_mac;
+  } else {
+    cerr
+      << "Invalid NewlineMode value: " << word << "\n";
+    newline_mode = PandaFileStreamBuf::NM_native;
+  }
+
+  return in;
+}
+
+#endif  // USE_PANDAFILESTREAM

dtool/src/dtoolutil/pandaFileStreamBuf.h

@@ -17,6 +17,8 @@
 
 #include "dtoolbase.h"
 
+#ifdef USE_PANDAFILESTREAM
+
 #if defined(_WIN32)
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
@@ -36,6 +38,15 @@ public:
   bool is_open() const;
   void close();
 
+  enum NewlineMode {
+    NM_native,
+    NM_binary,
+    NM_msdos,
+    NM_unix,
+    NM_mac,
+  };
+  static NewlineMode _newline_mode;
+
 protected:
   virtual streampos seekoff(streamoff off, ios_seekdir dir, ios_openmode which);
   virtual streampos seekpos(streampos pos, ios_openmode which);
@@ -53,8 +64,13 @@ private:
 
   size_t decode_newlines(char *dest, size_t dest_length,
                          const char *source, size_t source_length);
-  size_t encode_newlines(char *dest, size_t dest_length,
-                         const char *source, size_t source_length);
+
+  size_t encode_newlines_msdos(char *dest, size_t dest_length,
+                               const char *source, size_t source_length);
+  size_t encode_newlines_unix(char *dest, size_t dest_length,
+                              const char *source, size_t source_length);
+  size_t encode_newlines_mac(char *dest, size_t dest_length,
+                             const char *source, size_t source_length);
 
 private:
   string _filename;
@@ -74,4 +90,12 @@ private:
   streampos _gpos;
 };
 
+EXPCL_DTOOL ostream &
+operator << (ostream &out, PandaFileStreamBuf::NewlineMode newline_mode);
+
+EXPCL_DTOOL istream &
+operator >> (istream &in, PandaFileStreamBuf::NewlineMode &newline_mode);
+
+#endif  // USE_PANDAFILESTREAM
+
 #endif

dtool/src/prc/configPageManager.cxx

@@ -348,6 +348,12 @@ reload_implicit_pages() {
 
   _currently_loading = false;
   invalidate_cache();
+
+#ifdef USE_PANDAFILESTREAM
+  // Update this very low-level config variable here, for lack of any
+  // better place.
+  PandaFileStreamBuf::_newline_mode = newline_mode;
+#endif  // USE_PANDAFILESTREAM
 }
 
 ////////////////////////////////////////////////////////////////////

dtool/src/prc/config_prc.cxx

@@ -14,10 +14,22 @@
 
 #include "config_prc.h"
 #include "configVariableBool.h"
+#include "pandaFileStreamBuf.h"
 
 NotifyCategoryDef(prc, "");
 
 ConfigVariableBool assert_abort
 ("assert-abort", false,
- "Set this true to trigger a core dump and/or stack trace when the first assertion fails");
+ PRC_DESC("Set this true to trigger a core dump and/or stack trace when the first assertion fails"));
 
+#ifdef USE_PANDAFILESTREAM
+
+ConfigVariableEnum<PandaFileStreamBuf::NewlineMode> newline_mode
+("newline-mode", PandaFileStreamBuf::NM_native,
+  PRC_DESC("Controls how newlines are written by Panda applications writing "
+  "to a text file.  The default, \"native\", means to write newlines "
+  "appropriate to the current platform.  You may also specify \"binary\", "
+  "to avoid molesting the file data, or one of \"msdos\", \"unix\", "
+  "or \"mac\"."));
+  
+#endif  // USE_PANDAFILESTREAM

dtool/src/prc/config_prc.h

@@ -24,5 +24,9 @@ NotifyCategoryDecl(prc, EXPCL_DTOOLCONFIG, EXPTP_DTOOLCONFIG);
 
 extern ConfigVariableBool assert_abort;
 
+#ifdef USE_PANDAFILESTREAM
+extern ConfigVariableEnum<PandaFileStreamBuf::NewlineMode> newline_mode;
+#endif
+
 #endif