From 4539aedf46acf09af752d7c7a36a0de0ae5ca4be Mon Sep 17 00:00:00 2001
From: espen <espen>
Date: Mon, 12 Nov 2001 22:36:06 +0000
Subject: [PATCH] Added functions for version checks and variable querying

---
 tools/config.lisp | 84 ++++++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 71 insertions(+), 13 deletions(-)

diff --git a/tools/config.lisp b/tools/config.lisp
index 0b776e0..1623a57 100644
--- a/tools/config.lisp
+++ b/tools/config.lisp
@@ -1,25 +1,83 @@
-(defparameter *pkg-config* "/usr/bin/pkg-config")
+(defparameter *pkg-config* "pkg-config")
 
-(defun split-string (string &key (start 0) end)
+(defun split-string (string &key (start 0) (end (length string)))
   (let ((position (position #\sp string :start start :end end)))
-    (if position
-	(cons
+    (cond
+     ((zerop (- end start)) nil)
+     ((not position) (list (subseq string start end)))
+     ((= position start) (split-string string :start (1+ start) :end end))
+     (t	(cons
 	 (subseq string start position)
-	 (split-string string :start (1+ position) :end end))
-      (list (subseq string start end)))))
+	 (split-string string :start (1+ position) :end end))))))
 
-(defun run-pkg-config (package &rest options)
+
+(defun read-lines (&optional (stream *standard-input*))
+  (let ((line (read-line stream nil)))
+    (when line
+      (cons line (read-lines stream)))))
+
+
+(defun read-string (&optional (stream *standard-input*)
+		    (delimiter #\newline) (eof-error-p t) eof-value)
+  (let ((string (make-array 0 :element-type 'character
+			    :fill-pointer t :adjustable t)))
+    ;; I really need to learn how to use the loop facility
+    (labels ((read-chars ()
+               (let ((char (read-char stream (and eof-error-p delimiter))))
+		 (when char
+		   (vector-push-extend char string)
+		   (unless (eq char delimiter)
+		     (read-chars))))))
+      (read-chars))
+    (cond
+     ((not (zerop (length string))) string)
+     ((not eof-error-p) eof-value)
+     ((error 'end-of-file :stream stream)))))
+
+
+(defun run-pkg-config (package error &rest options)
   (let ((process
 	 (run-program
 	  *pkg-config* (cons package options) :wait t :output :stream)))
     (unless process
       (error "Unable to run ~A" *pkg-config*))
-    (unless (zerop (process-exit-code process))
-      (error "~A: ~A" *pkg-config* (read-line (process-output process))))
-    (prog1
-	(delete-if #'(lambda (str) (string= str "")) (split-string (read-line (process-output process))))
-      (process-close process))))
+    (let ((exit-code (process-exit-code process)))
+      (unless (or (not error) (zerop exit-code))
+	(error
+	 (or
+	  (read-string (process-error process) nil)
+	  (format nil "~A terminated with exit code ~A"
+		  *pkg-config* exit-code))))
+      (let ((output (read-lines (process-output process))))	  
+	(process-close process)
+	(values output exit-code)))))
 
 
 (defun pkg-cflags (package)
-  (run-pkg-config package "--cflags"))
+  (split-string (first (run-pkg-config package t "--cflags"))))
+
+
+(defun pkg-exists-p (package &key version atleast-version max-version
+		     ( error t))
+  (let ((version-check
+	 (cond
+	  (version (format nil "= ~A" version))
+	  (atleast-version (format nil ">= ~A" atleast-version))
+	  (max-version (format nil "<= ~A" max-version))
+	  (t ""))))
+    (if error
+	(progn
+	  (run-pkg-config package t "--print-errors" "--exists" version-check)
+	  t)
+      (multiple-value-bind (output exit-code)
+	  (run-pkg-config package nil "--exists" version-check)
+	(declare (ignore output))
+	(zerop exit-code)))))
+
+
+(defun pkg-version (package)
+  (first (run-pkg-config package t "--modversion")))
+
+
+(defun pkg-variable (package variable)
+  (first (run-pkg-config package t "--variable" variable)))
-- 
2.11.0