prism-auto: Add basic filtering of benchmarks using models.csv metadata.

New switch --filter-models X which restricts the list of models used from
a directory to those that match the filter X. Currently, this can refer to
the number of states and/or the model type. Examples:

* prism-auto . --filter-models "states>100 and states<10000"
* prism-auto . --filter-models "model_type=='DTMC'"
* prism-auto . --filter-models "'MC' in model_type"

The model metadata is by default read in from a models.csv file (as found,
for example, in the PRISM benchmark suite). The name of the file used can
be changed with --models-info FILE.

prism/etc/scripts/prism-auto

@@ -11,7 +11,7 @@
 
 # Run "prism-auto -h" for details of further options.
 
-import os,sys,re,subprocess,signal,tempfile,functools,logging,time,platform
+import os,sys,re,subprocess,signal,tempfile,functools,logging,time,platform,csv
 from pipes import quote
 from optparse import OptionParser
 from threading import Timer
@@ -143,8 +143,45 @@ def getModelsInDir(dir):
             if os.path.isfile(os.path.join(dir, file)) and isPrismModelFile(file):
                 modelFiles.append((os.path.join(dir, file), []))
     #print "Model files in " + dir + ": " + ' '.join( map(lambda pair: pair[0], modelFiles ))
+    
+    # If requested, filter the list of models
+    if options.filterModels:
+        modelFiles = filterModels(modelFiles, options.filterModels, dir)
+                
     return modelFiles
 
+# Restrict a list of models to those satisfying a filter expressed as a string
+# Examples: "states>100 and states<10000" or "model_type=='DTMC'"
+# Model list is given as pairs of files and argument lists (see getModelsInDir() above)
+# Model data is read in from a file models.csv (or something else if specified
+# using options.modelsInfoFilename)
+
+def filterModels(modelFiles, filterString, dir):
+    modelFilesNew = []
+    # Filter is false if the model metadata cannot be found
+    if os.path.isfile(os.path.join(dir, options.modelsInfoFilename)):
+        with open(os.path.join(dir, options.modelsInfoFilename), newline='') as csvfile:
+            # Build a list of models matching the filter
+            modelFilesFiltered = []
+            reader = csv.DictReader(csvfile)
+            for row in reader:
+                # Evaluate the filter using eval()
+                # Only provide access to the model type and number of states for now
+                # If any fields are missing, the filter evaluates to false
+                filterVarsAvailable = ['model_type', 'states']
+                filterVarsMissing = [key for key in filterVarsAvailable if key in filterString and not row[key]]
+                if not filterVarsMissing:
+                    if eval(filterString, {"__builtins__": {}}, {'model_type': row['model_type'], 'states': int(row['states'])}):
+                        model = os.path.join(dir, row['model_file'])
+                        if 'model_consts' in row:
+                            model += ' -const ' + row['model_consts']
+                        modelFilesFiltered.append(model)
+        # Restrict models list to ones in the list of filter matches
+        for modelFile in modelFiles:
+            if (modelFile[0] + ' ' + ' '.join(modelFile[1])).strip() in modelFilesFiltered:
+                modelFilesNew.append(modelFile)
+    return modelFilesNew;
+
 # Get a list of all files in the directory that satisfy the given predicate
 
 def getFilesInDir(dir, pred):
@@ -1031,6 +1068,8 @@ parser.add_option("--no-renaming", action="store_true", dest="noRenaming", defau
 parser.add_option("--debug", action="store_true", dest="debug", default=False, help="Enable debug mode: display debugging info")
 parser.add_option("--echo-full", action="store_true", dest="echoFull", default=False, help="An expanded version of -e/--echo")
 parser.add_option("--models-filename", dest="modelsFilename", metavar="X", default="models", help="Read in list of models/parameters for a directory from file X, if present [default=models]")
+parser.add_option("--models-info", dest="modelsInfoFilename", metavar="X", default="models.csv", help="Read model details from CSV file X, if present [default=models.csv]")
+parser.add_option("--filter-models", dest="filterModels", metavar="N", default="", help="Filter benchmark models...")
 parser.add_option("--log-subdirs", action="store_true", dest="logSubdirs" ,default=False, help="Organise PRISM output logs in subdirectories per benchmark argument")
 parser.add_option("--no-export-tests", action="store_true", dest="noExportTests", default=False, help="Don't check exported files when in test mode")
 parser.add_option("--skip-export-runs", action="store_true", dest="skipExportRuns", default=False, help="Skip all runs having exports")