2 files changed, 19 insertions, 7 deletions

diff --git a/Makefile b/Makefile
index d5b9661..bd1ed51 100644
--- a/Makefile
+++ b/Makefile
@@ -38,7 +38,7 @@ docker: ## Build docker image
         docker tag $(IMAGE_NAME):latest $(IMAGE_NAME):$(IMAGE_VERSION)
 
 docker-tests: ## Run docker image against the samples folder
-        @docker run --rm -v $(shell pwd)/data/samples:/data $(IMAGE_NAME):latest
+        @(docker run --rm -v $(shell pwd)/data/samples:/data $(IMAGE_NAME):latest && exit 1) || (test $$? -eq 255 || exit 1)
 
 docker-publish: ## Push docker image to the container registry
         @docker push $(IMAGE_NAME):latest
diff --git a/main.go b/main.go
index de64b90..d4976eb 100644
--- a/main.go
+++ b/main.go
@@ -30,6 +30,9 @@ const (
         FileBufferSize       = 32 * 1024 // 32KB
         YaraMaxThreads       = 32
         TempDirPrefix        = "pmf-"
+        ExitCodeOk           = 0
+        ExitCodeWithMatches  = 255
+        ExitCodeWithError    = 1
 )
 
 var (
@@ -93,7 +96,7 @@ func handleError(err error, desc string, isFatal bool) {
                 }
                 log.Println("[ERROR]"+desc, err)
                 if isFatal {
-                        os.Exit(1)
+                        os.Exit(ExitCodeWithError)
                 }
         }
 }
@@ -111,8 +114,9 @@ func writeRulesFiles(content fs.FS) string {
         for _, rulesFile := range rulesFiles {
                 // read embedded content
                 f, err := content.Open(path.Join("data", rulesFile))
-                handleError(err, "unable to read embedded rule", true)
+                handleError(err, "unable to open embedded rule", true)
                 ruleData, err := io.ReadAll(f)
+                handleError(err, "unable to read rule content", true)
 
                 // write to temporary file
                 err = os.WriteFile(path.Join(rulesPath, rulesFile), ruleData, 0640)
@@ -297,13 +301,14 @@ func loadRulesFile(fileName string) (*yara.Rules, error) {
 
 func main() {
         startTime := time.Now()
+        matchesFound := false
         _, err := flags.Parse(&args)
         if err != nil {
-                os.Exit(1)
+                os.Exit(ExitCodeWithError)
         }
         if args.ShowVersion {
                 println(version)
-                os.Exit(0)
+                os.Exit(ExitCodeOk)
         }
 
         // check rules path
@@ -317,7 +322,7 @@ func main() {
         // update rules if required
         if args.Update {
                 updateRules()
-                os.Exit(0)
+                os.Exit(ExitCodeOk)
         }
 
         // add custom excluded file extensions
@@ -428,6 +433,7 @@ func main() {
                         for target, count := range matchCount {
                                 if count >= DangerousMinScore {
                                         log.Println("[WARNING] dangerous file found:", target)
+                                        matchesFound = true
                                 }
                         }
                 } else { // single file mode
@@ -437,6 +443,7 @@ func main() {
                         err := scanner.SetCallback(&matches).ScanFile(args.Positional.Target)
                         handleError(err, "unable to scan target", true)
                         for _, match := range matches {
+                                matchesFound = true
                                 log.Println("[WARNING] match found:", args.Positional.Target, match.Rule)
                                 if args.Verbose {
                                         for _, matchString := range match.Strings {
@@ -460,6 +467,11 @@ func main() {
                         log.Println("[DEBUG] deleting temporary folder:", args.RulesDir)
                 }
                 err := os.RemoveAll(args.RulesDir)
-                handleError(err, "unable to delete temporary folder", true)
+                handleError(err, fmt.Sprintf("unable to delete temporary folder '%s'", args.RulesDir), false)
         }
+
+        if matchesFound {
+                os.Exit(ExitCodeWithMatches)
+        }
+        os.Exit(ExitCodeOk)
 }