cmd/mecha: allow passing build-time params to flash subcommand.

Signed-off-by: deadprogram <ron@hybridgroup.com>

Author: deadprogram

cmd/mecha/flash.go

@@ -39,13 +39,24 @@ func flash(cCtx *cli.Context) error {
 		intp += " debug"
 	}
 
-	var cmd *exec.Cmd
+	args := []string{"flash", "-size", "short", "-stack-size", "8kb", "-tags", intp, "-target", targetName}
+
+	if len(cCtx.StringSlice("params")) > 0 {
+		ldlags := ""
+		for _, p := range cCtx.StringSlice("params") {
+			ldlags += " -X " + p
+		}
+		args = append(args, "-ldflags", ldlags)
+	}
+
 	if cCtx.Bool("monitor") {
-		cmd = exec.Command("tinygo", "flash", "-size", "short", "-stack-size", "8kb", "-tags", intp, "-target", targetName, "-monitor", ".")
-	} else {
-		cmd = exec.Command("tinygo", "flash", "-size", "short", "-stack-size", "8kb", "-tags", intp, "-target", targetName, ".")
+		args = append(args, "-monitor")
 	}
 
+	args = append(args, ".")
+
+	var cmd = exec.Command("tinygo", args...)
+
 	var stdoutBuf, stderrBuf bytes.Buffer
 	cmd.Stdout = io.MultiWriter(&spinWriter{s, os.Stdout, false}, &stdoutBuf)
 	cmd.Stderr = io.MultiWriter(&spinWriter{s, os.Stderr, false}, &stderrBuf)

cmd/mecha/main.go

@@ -54,6 +54,10 @@ func main() {
 					&cli.BoolFlag{Name: "monitor", Aliases: []string{"m"}, Usage: "monitor the serial port after flashing"},
 					&cli.StringFlag{Name: "interpreter", Aliases: []string{"i"}, Value: "wazero", Usage: "WebAssembly interpreter to use (wasman, wazero)"},
 					&cli.BoolFlag{Name: "debug", Aliases: []string{"d"}, Usage: "perform additional logging for debugging"},
+					&cli.StringSliceFlag{
+						Name:  "params",
+						Usage: "Pass build-time parameters for the application. Format: -params main.name=value -params main.descript=value2",
+					},
 				},
 			},
 			{