Add scheme wrapper.

* scm/extent-sampling/load-libs.scm.in, scm/extent-sampling/wrap.scm:
New files.
* CMakeLists.txt: Check for guile. Build and install scheme wrapper.
(change_extension): New function.

3 files changed, 237 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 935c3b3..beae2ff 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,6 +4,15 @@ project(extent-sampling VERSION 0.1.0)
 find_package(GSL REQUIRED)
 find_program(SC NAMES sc REQUIRED)
 find_program(INDENT NAMES indent)
+# TODO: Maybe, support other versions of guile such as 2.2.
+pkg_check_modules(GUILE guile-3.0)
+pkg_get_variable(GUILD guile-3.0 guild)
+
+function(change_extension var filename extension)
+  get_filename_component(basename ${filename} NAME_WE)
+  get_filename_component(dirname ${filename} DIRECTORY)
+  set(${var} ${dirname}/${basename}.${extension} PARENT_SCOPE)
+endfunction()
 
 # Generate C source files from SC source files, and optionally indent
 # them.
@@ -37,3 +46,26 @@ set_target_properties(extentsampling PROPERTIES
   PUBLIC_HEADER "include/extent-sampling.h;include/gaussian-nd-random.h;include/nd-random.h;include/oracles.h")
 install(TARGETS extentsampling LIBRARY
   PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/extent-sampling)
+
+# Build and install scheme wrapper.
+if(${GUILE_FOUND})
+  configure_file(scm/extent-sampling/load-libs.scm.in scm/extent-sampling/load-libs.scm)
+  set(SCM_WRAPPER_PATH scm/extent-sampling/wrap.scm)
+  change_extension(SCM_WRAPPER_GO_PATH ${SCM_WRAPPER_PATH} go)
+  add_custom_command(
+    OUTPUT ${SCM_WRAPPER_GO_PATH}
+    COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_SOURCE_DIR}/${SCM_WRAPPER_PATH} ${CMAKE_BINARY_DIR}/${SCM_WRAPPER_PATH}
+    COMMAND ${GUILD} compile ${CMAKE_BINARY_DIR}/${SCM_WRAPPER_PATH} -o ${CMAKE_BINARY_DIR}/${SCM_WRAPPER_GO_PATH}
+    DEPENDS ${SCM_WRAPPER_PATH}
+    VERBATIM)
+  add_custom_target(scheme ALL DEPENDS ${SCM_WRAPPER_GO_PATH})
+  string(REPLACE "." ";" GUILE_VERSION_LIST ${GUILE_VERSION})
+  list(GET GUILE_VERSION_LIST 0 GUILE_MAJOR_VERSION)
+  list(GET GUILE_VERSION_LIST 1 GUILE_MINOR_VERSION)
+  install(FILES ${CMAKE_BINARY_DIR}/scm/extent-sampling/load-libs.scm
+    DESTINATION ${CMAKE_INSTALL_DATADIR}/guile/site/${GUILE_MAJOR_VERSION}.${GUILE_MINOR_VERSION}/extent-sampling)
+  install(FILES ${CMAKE_BINARY_DIR}/${SCM_WRAPPER_PATH}
+    DESTINATION ${CMAKE_INSTALL_DATADIR}/guile/site/${GUILE_MAJOR_VERSION}.${GUILE_MINOR_VERSION}/extent-sampling)
+  install(FILES ${CMAKE_BINARY_DIR}/${SCM_WRAPPER_GO_PATH}
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/guile/site/${GUILE_MAJOR_VERSION}.${GUILE_MINOR_VERSION}/site-ccache/extent-sampling)
+endif()
diff --git a/scm/extent-sampling/load-libs.scm.in b/scm/extent-sampling/load-libs.scm.in
new file mode 100644
index 0000000..1b99e53
--- /dev/null
+++ b/scm/extent-sampling/load-libs.scm.in
@@ -0,0 +1,13 @@
+(define lib-extentsampling
+  (catch #t
+    (lambda ()
+      (dynamic-link "@CMAKE_INSTALL_FULL_LIBDIR@/libextentsampling"))
+    (lambda _
+      (dynamic-link "libextentsampling"))))
+
+(define lib-gsl
+  (catch #t
+    (lambda ()
+      (dynamic-link "@GSL_LIBRARY@"))
+    (lambda _
+      (dynamic-link "libgsl"))))
diff --git a/scm/extent-sampling/wrap.scm b/scm/extent-sampling/wrap.scm
new file mode 100644
index 0000000..180ac91
--- /dev/null
+++ b/scm/extent-sampling/wrap.scm
@@ -0,0 +1,192 @@
+(define-module (extent-sampling wrap)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:use-module (ice-9 match)
+  #:use-module (system foreign))
+
+(include "load-libs.scm")
+
+(define (make-gsl-alloc allocator-name allocator-args freer-name)
+  (lambda args
+    (let ((obj
+           (apply (pointer->procedure
+                   '* (dynamic-func allocator-name lib-gsl) allocator-args)
+                  args)))
+      (set-pointer-finalizer! obj (dynamic-func freer-name lib-gsl))
+      obj)))
+
+(define-public pi
+  ((pointer->procedure double
+                       (dynamic-func "pi" lib-extentsampling)
+                       (list))))
+
+(define-public volume-of-ball
+  (pointer->procedure double
+                      (dynamic-func "volume_of_ball" lib-extentsampling)
+                      (list int)))
+
+(define-public surface-area-of-ball
+  (pointer->procedure double
+                      (dynamic-func "surface_area_of_ball" lib-extentsampling)
+                      (list int)))
+
+(define-public angle-between-vectors
+  (pointer->procedure double
+                      (dynamic-func "angle_between_vectors" lib-extentsampling)
+                      (list '* '*)))
+
+(define-public planar-angle->solid-angle
+  (pointer->procedure double
+                      (dynamic-func "planar_angle_to_solid_angle" lib-extentsampling)
+                      (list double int)))
+
+;; Random state
+
+(define %gsl-random-state
+  ((make-gsl-alloc "gsl_rng_alloc" (list '*) "gsl_rng_free")
+   (dereference-pointer
+    (dynamic-pointer "gsl_rng_default" lib-gsl))))
+
+(define-public (set-gsl-random-state! seed)
+  ((pointer->procedure void
+                       (dynamic-func "gsl_rng_set" lib-gsl)
+                       (list '* unsigned-long))
+   %gsl-random-state seed))
+
+(define-public random-flat
+  (cut (pointer->procedure double
+                           (dynamic-func "gsl_ran_flat" lib-gsl)
+                           (list '* double double))
+    %gsl-random-state <> <>))
+
+;; Vector functions
+
+(define vector-alloc
+  (make-gsl-alloc "gsl_vector_alloc" (list int) "gsl_vector_free"))
+
+(define-public (vector-size vector)
+  (match (parse-c-struct vector
+                         (list size_t size_t '* '* int))
+    ((size _ _ _ _) size)))
+
+(define-public (vector-scale! vector k)
+  "Scale VECTOR by a factor K."
+  ((pointer->procedure int
+                       (dynamic-func "gsl_vector_scale" lib-gsl)
+                       (list '* double))
+   vector k)
+  vector)
+
+(define-public (vector-norm2 vector)
+  ((pointer->procedure double
+                       (dynamic-func "gsl_blas_dnrm2" lib-gsl)
+                       (list '*))
+   vector))
+
+(define-public (vector-add! u v)
+  "Return the vector sum of vectors U and V. The sum is stored in U."
+  ((pointer->procedure int
+                       (dynamic-func "gsl_vector_add" lib-gsl)
+                       (list '* '*))
+   u v)
+  u)
+
+(define-public (basis n dimension)
+  "Return the basis vector in the Nth canonical direction."
+  (let ((vector (vector-alloc dimension)))
+    ((pointer->procedure void
+                         (dynamic-func "gsl_vector_set_basis" lib-gsl)
+                         (list '* int))
+     vector n)
+    vector))
+
+;; Histogram functions
+
+(define histogram-struct
+  (list size_t '* '*))
+
+(define (histogram-alloc bins min max)
+  (let ((histogram
+         ((make-gsl-alloc "gsl_histogram_alloc" (list size_t) "gsl_histogram_free")
+          bins)))
+    ((pointer->procedure int
+                         (dynamic-func "gsl_histogram_set_ranges_uniform" lib-gsl)
+                         (list '* double double))
+     histogram min max)
+    histogram))
+
+(define-public (histogram->points histogram)
+  (match (parse-c-struct histogram histogram-struct)
+    ((n range bin)
+     (let ((range (array->list (pointer->bytevector range (1+ n) 0 'f64))))
+       (map cons
+            (drop-right range 1)
+            (array->list (pointer->bytevector bin n 0 'f64)))))))
+
+(define-public (histogram->pdf histogram)
+  (match (parse-c-struct histogram histogram-struct)
+    ((n range bin)
+     (let ((range (pointer->bytevector range (1+ n) 0 'f64)))
+       ((pointer->procedure int
+                            (dynamic-func "gsl_histogram_scale" lib-extentsampling)
+                            (list '* double))
+        histogram
+        (/ n
+           (- (array-ref range n)
+              (array-ref range 0))
+           (fold + 0 (array->list (pointer->bytevector bin n 0 'f64)))))
+       histogram))))
+
+(define-public (rhistogram bins min max)
+  (case-lambda
+    (() (histogram-alloc bins min max))
+    ((histogram) histogram)
+    ((histogram input)
+     ((pointer->procedure int
+                          (dynamic-func "gsl_histogram_increment" lib-extentsampling)
+                          (list '* double))
+      histogram input)
+     histogram)))
+
+;; nd-random
+
+(define-public (random-direction-vector dimension)
+  (let ((vector (vector-alloc dimension)))
+    ((pointer->procedure void
+                         (dynamic-func "random_direction_vector" lib-extentsampling)
+                         (list '* '*))
+     %gsl-random-state vector)
+    vector))
+
+(define-public (subsampling-random-vector mean max-theta)
+  (let ((vector (vector-alloc (vector-size mean))))
+    ((pointer->procedure void
+                         (dynamic-func "subsampling_random_vector" lib-extentsampling)
+                         (list '* '* double '*))
+     %gsl-random-state mean max-theta vector)
+    vector))
+
+(define-public (shifted-gaussian-random-vector mean max-theta standard-deviation)
+  (let* ((vector (vector-alloc (vector-size mean)))
+         (cost
+          ((pointer->procedure int
+                               (dynamic-func "shifted_gaussian_random_vector" lib-extentsampling)
+                               (list '* '* double double '*))
+           %gsl-random-state mean max-theta standard-deviation vector)))
+    vector))
+
+(define-public (shifted-gaussian-random-vector-cost mean max-theta standard-deviation)
+  ((pointer->procedure int
+                         (dynamic-func "shifted_gaussian_random_vector" lib-extentsampling)
+                         (list '* '* double double '*))
+   %gsl-random-state mean max-theta standard-deviation (vector-alloc (vector-size mean))))
+
+(define %integration-workspace
+  ((make-gsl-alloc "gsl_integration_workspace_alloc" (list size_t) "gsl_integration_workspace_free")
+   1000))
+
+(define-public (shifted-gaussian-pdf theta mean max-theta standard-deviation)
+  ((pointer->procedure double
+                       (dynamic-func "shifted_gaussian_pdf" lib-extentsampling)
+                       (list double double double double unsigned-int '*))
+   theta (vector-norm2 mean) max-theta standard-deviation (vector-size mean) %integration-workspace))