func main() {
runtime.GOMAXPROCS(runtime.NumCPU())
cmdargs := cmdline.Cmdline()
if cmdargs.Err != nil {
fmt.Fprintf(os.Stderr, "Failed to parse commandline: %s", cmdargs.Err)
os.Exit(1)
}
if cmdargs.Filepath != "" {
// algo is already validated by cmdline.Cmdline
img := img.BuildImg(&cmdargs.ImgParams)
if err := cmdline.WriteImg(img, cmdargs.Filepath); err != nil {
fmt.Fprintf(os.Stderr, "Failed to write Image to file: %s", err)
os.Exit(1)
}
os.Exit(0)
}
if cmdargs.Ssocket != "" {
http.HandleFunc("/", web.ServeHTTP)
// Forever
err := http.ListenAndServe(cmdargs.Ssocket, nil)
if err != nil {
fmt.Fprintf(os.Stderr, "Failed to start http server: %s", err)
os.Exit(1)
}
}
// Never reached, cmdline.Cmdline() makes sure that either cmdargs.Filepath
// or cmdargs.Ssocket evaluates to true.
}
// ServeHTTP responds with a PNG image of desired fractal to the client.
func ServeHTTP(rW http.ResponseWriter, r *http.Request) {
var err error
imgP, err := getHTTPReqData(r)
if err != nil {
rW.Header().Set("Content-Type", "text/plain")
msg := fmt.Sprintf("getHTTPReqData failed: %v", err)
if _, err = io.WriteString(rW, msg); err != nil {
msg = msg + ", and io.WriteString failed as well (???)"
fmt.Fprintf(os.Stderr, msg)
os.Exit(1)
}
return
}
rW.Header().Set("Content-Type", "img/png")
imgRes := img.BuildImg(imgP)
err = png.Encode(rW, imgRes) // NOTE: ignoring errors
if err != nil {
fmt.Fprintf(os.Stderr, "Error while sending image to client: %v\n", err)
}
}