initial

7 files changed, 840 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..567609b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+build/
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..a0b2d6b
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,160 @@
+project("csound_nstrexists")
+
+cmake_minimum_required(VERSION 3.8)
+
+set(APIVERSION "6.0")
+
+# Release or Debug
+set(CMAKE_BUILD_TYPE "Release")
+
+# force make to print the command lines
+set(CMAKE_VERBOSE_MAKEFILE on)
+
+# path to Csound cmake module
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
+
+# set compilation flags
+set(CMAKE_C_FLAGS  ${CMAKE_C_FLAGS}  "-fpermissive -fPIC -w -DUSE_DOUBLE -DB64BIT")
+
+# options
+option(USE_LIB64 "Set to on to set installation dir for libs to lib64" OFF)
+option(USE_DOUBLE "Use doubles for audio calculations" ON)
+
+set(BUILDING_CSOUND_PLUGINS ON)
+
+# ----------------------------------------------
+
+include(FindCsound)
+
+include(CheckCCompilerFlag)
+
+# -----------------------------------------------
+
+function(addflag flag flagname)
+  check_c_compiler_flag(${flag} ${flagname})
+  if (${flagname})
+    # message(STATUS "Setting C flag ${flag}")    
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}" PARENT_SCOPE)
+  endif()
+endfunction(addflag)
+
+
+MACRO(SUBDIRLIST result curdir)
+  FILE(GLOB children RELATIVE ${curdir} ${curdir}/*)
+  SET(dirlist "")
+  FOREACH(child ${children})
+    message(STATUS "looking at ${child}")
+    IF(IS_DIRECTORY ${curdir}/${child})
+        LIST(APPEND dirlist ${child})
+    ENDIF()
+  ENDFOREACH()
+  SET(${result} ${dirlist})
+ENDMACRO()
+
+  
+MACRO(ADD_ALL_SUBDIRECTORIES directory)
+  subdirlist(SUBDIRS ${directory})
+  message(STATUS "Found subdirs: ${SUBDIRS}")
+  foreach(SUBDIR ${SUBDIRS})
+    set(thissubdir "${directory}/${SUBDIR}")
+    if(EXISTS "${directory}/${SUBDIR}/CMakeLists.txt")
+      message(STATUS "Adding subdir: ${thissubdir}")
+      add_subdirectory(${directory}/${SUBDIR})
+    else()
+      message(WARNING "Skipping ${directory}/${SUBDIR} because no CMakeLists.txt file was found")
+    endif()
+  endforeach()
+ENDMACRO()
+
+
+
+# set optimization flags
+if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_COMPILER_IS_CLANG)
+  add_definitions(-fvisibility=hidden)
+  if(NATIVE)
+	add_definitions(-march=native)
+  endif()
+  
+  include(CheckCCompilerFlag)
+  include(CheckCXXCompilerFlag)
+
+  addflag(-msse HAS_SSE)
+  addflag(-msse2 HAS_SSE2)
+  addflag(-mfgpath=sse HAS_FPMATH_SSE)
+  
+endif()
+
+if(MINGW)
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -mstackrealign")
+endif()
+
+addflag(-ftree-vectorize HAS_TREE_VECTORIZE)
+addflag(-ffast-math HAS_FAST_MATH)
+addflag(-fomit-frame-pointer HAS_OMIT_FRAME_POINTER)
+
+
+# -------------------------------------------------------------------
+
+set(CS_FRAMEWORK_DEST "~/Library/Frameworks")
+
+
+if(USE_LIB64)
+  set(LIBRARY_INSTALL_DIR "lib64")
+  add_definitions("-DLIB64")
+else()
+  set(LIBRARY_INSTALL_DIR "lib")
+endif()
+
+message(STATUS "LIBRARY INSTALL DIR: ${LIBRARY_INSTALL_DIR}")
+
+# -------------------------------------------------------------------
+
+
+if(USE_DOUBLE)
+  message(STATUS ">>> using doubles")
+  
+  if(APPLE)
+    set(CSOUNDLIB "CsoundLib64")
+    set(PLUGIN_INSTALL_DIR "${CS_FRAMEWORK_DEST}/${CSOUNDLIB}.framework/Versions/${APIVERSION}/Resources/Opcodes64")
+  else()
+    set(CSOUNDLIB "csound64")
+    set(PLUGIN_INSTALL_DIR "${LIBRARY_INSTALL_DIR}/csound/plugins64-${APIVERSION}")
+  endif()
+else()
+  message(STATUS ">>> not using doubles")
+  if(APPLE)
+    set(CSOUNDLIB "CsoundLib")
+    set(PLUGIN_INSTALL_DIR "${CS_FRAMEWORK_DEST}/${CSOUNDLIB}.framework/Versions/${APIVERSION}/Resources/Opcodes")
+  else()
+    set(CSOUNDLIB "csound")
+    set(PLUGIN_INSTALL_DIR "${LIBRARY_INSTALL_DIR}/csound/plugins-${APIVERSION}")
+  endif()
+endif()
+
+
+# -------------------------------------------------------------------
+  
+# Csound opcode build
+find_package(Csound)
+
+
+set(BUILD_PLUGINS_DIR ${CMAKE_CURRENT_BINARY_DIR})
+
+if(NOT CSOUND_FOUND)
+  message(FATAL_ERROR "Csound installation not found")
+endif()
+
+set(CFILES src/opcodes.c)
+
+include_directories(${CSOUND_INCLUDE_DIRS})
+include_directories(include)
+
+
+add_library(nstrexists SHARED ${CFILES})
+
+set_target_properties(nstrexists PROPERTIES
+  RUNTIME_OUTPUT_DIRECTORY ${BUILD_PLUGINS_DIR}
+  LIBRARY_OUTPUT_DIRECTORY ${BUILD_PLUGINS_DIR})
+ 
+install(TARGETS nstrexists LIBRARY DESTINATION "${PLUGIN_INSTALL_DIR}" )
+
diff --git a/LICENCE b/LICENCE
new file mode 100644
index 0000000..de9fd5a
--- /dev/null
+++ b/LICENCE
@@ -0,0 +1,502 @@
+		  GNU LESSER GENERAL PUBLIC LICENSE
+		       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+     51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
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+AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU
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+CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
+LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
+RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
+FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
+
+		     END OF TERMS AND CONDITIONS
+^L
+           How to Apply These Terms to Your New Libraries
+
+  If you develop a new library, and you want it to be of the greatest
+possible use to the public, we recommend making it free software that
+everyone can redistribute and change.  You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms of the
+ordinary General Public License).
+
+  To apply these terms, attach the following notices to the library.  It is
+safest to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least the
+"copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the library's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the library, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..34abd9d
--- /dev/null
+++ b/README.md
@@ -0,0 +1,30 @@
+## Introduction
+csound-nstrexists provides a simple way to check whether an instrument number exists in the orchestra, at i-rate or k-rate. An example csd is provided in the examples/ directory demonstrating i and k-rate operation.
+This depends on changes in commit cca2bd90bffc5c36499c74734e37ec256dc60924 on 2019-09-12 so it will not work with builds older than that.
+The opcode has only been tested on Linux as of writing.
+
+
+## Requirements
+ - Csound development libraries
+ - Cmake
+
+
+## Building
+Create a build directory at the top of the source tree, execute *cmake ..*, *make* and optionally *make install* as root. If the latter is not used/possible then the resulting libnstrexists module can be used with the *--opcode-lib* flag in Csound. eg:
+	
+	cd csound-nstrexists
+	mkdir build && cd build
+	cmake ..
+	make && sudo make install
+
+
+## Opcode overview
+### nstrexists
+*iexists nstrexists instrnum*
+*kexists nstrexists knstrnum*
+
+Check if an instrument exists given the instrument number.
+ - iexists | kexists : 1 if instrument is found, 0 if not
+ 
+ - instrnum | knstrnum : the instrument number to check
+
diff --git a/cmake/Modules/FindCsound.cmake b/cmake/Modules/FindCsound.cmake
new file mode 100644
index 0000000..e55b269
--- /dev/null
+++ b/cmake/Modules/FindCsound.cmake
@@ -0,0 +1,29 @@
+# Try to find the Csound library.
+# Once done this will define:
+#  CSOUND_FOUND - System has the Csound library
+#  CSOUND_INCLUDE_DIRS - The Csound include directories.
+#  CSOUND_LIBRARIES - The libraries needed to use the Csound library.
+
+if(APPLE)
+find_path(CSOUND_INCLUDE_DIR csound.h HINTS /Library/Frameworks/CsoundLib64.framework/Headers
+"$ENV{HOME}/Library/Frameworks/CsoundLib64.framework/Headers")
+else()
+find_path(CSOUND_INCLUDE_DIR csound.h PATH_SUFFIXES csound)
+endif()
+
+if(APPLE)
+find_library(CSOUND_LIBRARY NAMES CsoundLib64 HINTS /Library/Frameworks/CsoundLib64.framework/
+"$ENV{HOME}/Library/Frameworks/CsoundLib64.framework")
+else()
+find_library(CSOUND_LIBRARY NAMES csound64 csound)
+endif()
+
+include(FindPackageHandleStandardArgs)
+# handle the QUIETLY and REQUIRED arguments and set CSOUND_FOUND to TRUE
+# if all listed variables are TRUE
+find_package_handle_standard_args(CSOUND
+                                  CSOUND_LIBRARY CSOUND_INCLUDE_DIR)
+mark_as_advanced(CSOUND_INCLUDE_DIR CSOUND_LIBRARY)
+
+set(CSOUND_INCLUDE_DIRS ${CSOUND_INCLUDE_DIR})
+set(CSOUND_LIBRARIES ${CSOUND_LIBRARY} )
diff --git a/examples/example.csd b/examples/example.csd
new file mode 100644
index 0000000..9c51083
--- /dev/null
+++ b/examples/example.csd
@@ -0,0 +1,69 @@
+<CsoundSynthesizer>
+<CsOptions>
+-n ; no audio
+</CsOptions>
+<CsInstruments>
+/*
+	Demonstration of nstrexists.
+	Check through a range of instrument numbers and report if they are
+	known to the Csound engine.
+
+*/
+sr = 44100
+ksmps = 1
+nchnls = 2
+0dbfs = 1
+
+/* 
+	Empty instruments to test for existence 
+*/
+instr 92
+endin
+
+instr 93
+endin
+
+instr 95
+endin
+
+instr testinstr1
+endin
+
+instr testinstr3
+endin
+
+instr testinstr4
+endin
+
+
+/*
+	Go through instrument numbers 1 to 10 and check for existence
+*/
+instr 98
+
+	; test the numeric i-rate opcode: look for instruments numbered between 91 and 98
+	inum = 91
+loop:
+	prints(sprintf("(i-rate) Instr %d : %d\n", inum, nstrexists(inum)))
+	loop_lt inum, 1, 99, loop
+	turnoff
+endin
+
+
+instr 99
+
+	; test the numeric k-rate opcode: look for instruments numbered between 91 and 98
+	knum = 91
+loop:
+	printks2(sprintfk("(k-rate) Instr %d: %d\n", knum, nstrexists(knum)), knum)
+	loop_lt knum, 1, 99, loop
+	turnoff
+endin
+
+</CsInstruments>
+<CsScore>
+i98 0 1
+i99 1 1
+</CsScore>
+</CsoundSynthesizer>
+
diff --git a/src/opcodes.c b/src/opcodes.c
new file mode 100644
index 0000000..5bc30ef
--- /dev/null
+++ b/src/opcodes.c
@@ -0,0 +1,49 @@
+/*
+    opcodes.cpp
+    Copyright (C) 2021 Richard Knight
+
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 3 of the License, or (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program; if not, write to the Free Software Foundation,
+    Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ 
+ */
+
+
+#include "csdl.h"
+
+// struct for numeric opcode
+typedef struct _nstrexists_t {
+	OPDS h;
+	MYFLT *out;
+	MYFLT *in;
+} nstrexists_t;
+
+
+// numeric opcode
+int nstrexists(CSOUND *csound, nstrexists_t *p) {
+	if (NULL != csound->GetInstrument(csound, (int)*p->in, NULL)) {
+		*(p->out) = FL(1);
+	} else {
+		*(p->out) = FL(0);
+	}
+	return OK;
+}
+
+
+static OENTRY localops[] = {
+	{"nstrexists", sizeof(nstrexists_t), 0, 1, "i", "i", (SUBR) nstrexists, NULL, NULL},
+	{"nstrexists.k", sizeof(nstrexists_t), 0, 3, "k", "k", (SUBR) nstrexists, (SUBR) nstrexists, NULL},
+};
+
+LINKAGE