From dde3bda516bb4d84922e4068c77ee4b4b7492342 Mon Sep 17 00:00:00 2001
From: Amy Gale Ruth Bowersox <amy@erbosoft.com>
Date: Fri, 6 Dec 2019 22:37:20 -0700
Subject: [PATCH] added command line parsing for options

---
 src/config.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 src/config.h |  2 +-
 src/main.c   |  6 ++++-
 3 files changed, 81 insertions(+), 3 deletions(-)

diff --git a/src/config.c b/src/config.c
index f16c844..1ede164 100644
--- a/src/config.c
+++ b/src/config.c
@@ -1,7 +1,25 @@
 #include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 #include "config.h"
 #include "log.h"
 
+static const struct option long_options[] = {
+  {"framebuffer", required_argument, 0, 'F'},
+  {"help",        no_argument,       0, 'h'},
+  { NULL,         0,                 0,  0 }
+};
+
+static const char *short_options = "F:h";
+
+static const char *helptext =
+  "UPIWIN - Micro Pi Windows server program\n\n"
+  "Usage: upiwin [options] scriptname [scriptargs]\n\n"
+  "Available options:\n"
+  "  -F,--framebuffer [devname] - Specifies the framebuffer device name\n"
+  "  -h,--help - Displays this help message.\n"
+  "";
+
 #define EXITFUNCBLOCK_FUNCCOUNT 64
 
 typedef struct tagEXITFUNCBLOCK
@@ -38,14 +56,70 @@ static void init_defaults(void)
   Gconfig.sys_mq_length = 64;
 }
 
-HRESULT Config_setup(void)
+static HRESULT parse_cmdline(int argc, char *argv[], GLOBAL_CONFIG *parsed)
 {
+  int c;
+  PSTR pstr;
+  BOOL help = FALSE;
+
+  memset(parsed, 0, sizeof(GLOBAL_CONFIG));
+  for (;;)
+  {
+    c = getopt_long(argc, argv, short_options, long_options, NULL);
+    if (c==-1)
+      break;
+    switch (c)
+    {
+      case 'F':
+	pstr = strdup(optarg);
+	if (!pstr)
+	{
+	  Log(LERROR, "Out of memory in parse_cmdline");
+	  return E_OUTOFMEMORY;
+	}
+	if (parsed->framebuffer_device)
+	  free(parsed->framebuffer_device);
+	parsed->framebuffer_device = pstr;
+	break;
+
+      case 'h':
+	help = TRUE;
+	break;
+
+      default:
+	fprintf(stderr, "%s: unexpected option -%c\n", argv[0], c);
+	return E_UNEXPECTED;
+    }
+  }
+  if (help)
+  {
+    fputs(helptext, stdout);
+    return S_FALSE;
+  }
+  return S_OK;
+}
+
+static void overlay_config(GLOBAL_CONFIG *p)
+{
+  if (p->framebuffer_device)
+    Gconfig.framebuffer_device = p->framebuffer_device;
+}
+
+HRESULT Config_setup(int argc, char *argv[])
+{
+  HRESULT hr;
+  GLOBAL_CONFIG from_commandline;
+  
   if (atexit(run_exit_funcs))
   {
     Log(LFATAL, "Unable to set up exit function mechanism");
     return E_FAIL;
   }
   init_defaults();
+  hr = parse_cmdline(argc, argv, &from_commandline);
+  if (hr != S_OK)
+    return hr;
+  overlay_config(&from_commandline)
   return S_OK;
 }
 
diff --git a/src/config.h b/src/config.h
index b716af5..4916612 100644
--- a/src/config.h
+++ b/src/config.h
@@ -13,7 +13,7 @@ typedef struct tagGLOBAL_CONFIG {
 
 extern GLOBAL_CONFIG Gconfig;
 
-extern HRESULT Config_setup(void);
+extern HRESULT Config_setup(int argc, char *argv[]);
 extern HRESULT Config_exitfunc(PEXITFUNC pfn);
 
 #endif /* __CONFIG_H_INCLUDED */
diff --git a/src/main.c b/src/main.c
index d56555b..8716e56 100644
--- a/src/main.c
+++ b/src/main.c
@@ -27,13 +27,17 @@ static void do_draw(void)
 
 int main(int argc, char *argv[])
 {
+  HRESULT hr;
   int running = 1;
   MSG msg;
   char *tmp;
 
   Time_init();
-  if (FAILED(Config_setup()))
+  hr = Config_setup(argc, argv);
+  if (FAILED(hr))
     return EXIT_FAILURE;
+  else if (hr != S_OK)
+    return EXIT_SUCCESS;
   if (FAILED(Fb_setup()))
     return EXIT_FAILURE;
   if (FAILED(Gpio_setup()))