added global configuration data block and our own "atexit" type mechanism

that doesn't depend on enough free slots in the C library

src/config.c

@@ -0,0 +1,70 @@
+#include <stdlib.h>
+#include "config.h"
+#include "log.h"
+
+#define EXITFUNCBLOCK_FUNCCOUNT 64
+
+typedef struct tagEXITFUNCBLOCK
+{
+  struct tagEXITFUNCBLOCK *next;
+  int num_funcs;
+  PEXITFUNC funcs[EXITFUNCBLOCK_FUNCCOUNT];
+} EXITFUNCBLOCK, *PEXITFUNCBLOCK;
+
+/* The global configuration data */
+GLOBAL_CONFIG Gconfig;
+
+static PEXITFUNCBLOCK exitfuncs = NULL;
+
+static void run_exit_funcs(void)
+{
+  int i;
+  PEXITFUNCBLOCK p;
+  
+  while (exitfuncs)
+  {
+    p = exitfuncs;
+    exitfuncs = p->next;
+    for (i = p->num_funcs - 1; i >= 0; i++)
+      (*(p->funcs[i]))();
+    free(p);
+  }
+}
+
+static void init_defaults(void)
+{
+  Gconfig.framebuffer_device = "/dev/fb1";
+  Gconfig.button_debounce = 100;
+  Gconfig.sys_mq_length = 64;
+}
+
+HRESULT Config_setup(void)
+{
+  if (atexit(run_exit_funcs))
+  {
+    Log(LFATAL, "Unable to set up exit function mechanism");
+    return E_FAIL;
+  }
+  init_defaults();
+  return S_OK;
+}
+
+HRESULT Config_exitfunc(PEXITFUNC pfn)
+{
+  PEXITFUNCBLOCK p;
+  
+  if (!exitfuncs || (exitfuncs->num_funcs == EXITFUNCBLOCK_FUNCCOUNT))
+  {
+    p = (PEXITFUNCBLOCK)malloc(sizeof(EXITFUNCBLOCK));
+    if (!p)
+    {
+      Log(LERROR, "unable to allocate another exit function block");
+      return E_OUTOFMEMORY;
+    }
+    p->next = exitfuncs;
+    p->num_funcs = 0;
+    exitfuncs = p;
+  }
+  exitfuncs->funcs[exitfuncs->num_funcs++] = pfn;
+  return S_OK;
+}

src/config.h

@@ -0,0 +1,19 @@
+#ifndef __CONFIG_H_INCLUDED
+#define __CONFIG_H_INCLUDED
+
+#include "wintype.h"
+
+typedef void (*PEXITFUNC)(void);
+
+typedef struct tagGLOBAL_CONFIG {
+  PCSTR framebuffer_device;
+  UINT32 button_debounce;
+  UINT32 sys_mq_length;
+} GLOBAL_CONFIG;
+
+extern GLOBAL_CONFIG Gconfig;
+
+extern HRESULT Config_setup(void);
+extern HRESULT Config_exitfunc(PEXITFUNC pfn);
+
+#endif /* __CONFIG_H_INCLUDED */

src/fbinit.c

@@ -6,6 +6,7 @@
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <linux/fb.h>
+#include "config.h"
 #include "log.h"
 #include "fbinit.h"
 #include "scode.h"
@@ -27,13 +28,25 @@ inline static UINT16 makemask(unsigned offset, unsigned length)
   return (UINT16)(((1 << length) - 1) << offset);
 }
 
+static void do_cleanup(void)
+{
+  /* additional cleanup here */
+  
+  memset(Fb_Ptr, 0, local_info.screenbytes);
+  munmap((void *)Fb_Ptr, local_info.screenbytes);
+  Fb_Ptr = NULL;
+  
+  close(fb_fd);
+  fb_fd = -1;
+}
+
 HRESULT Fb_setup(void)
 {
   HRESULT hr = S_OK;
   struct fb_fix_screeninfo fixed;
   struct fb_var_screeninfo var;
   
-  fb_fd = open("/dev/fb1", O_RDWR);
+  fb_fd = open(Gconfig.framebuffer_device, O_RDWR);
   if (fb_fd == -1)
   {
     hr = ERRNO_AS_SCODE;
@@ -89,21 +102,12 @@ HRESULT Fb_setup(void)
 
   /* additional setup here */
 
+  hr = Config_exitfunc(do_cleanup);
+  if (FAILED(hr))
+    do_cleanup();
   return hr;
 }
 
-void Fb_cleanup(void)
-{
-  /* additional cleanup here */
-  
-  memset(Fb_Ptr, 0, local_info.screenbytes);
-  munmap((void *)Fb_Ptr, local_info.screenbytes);
-  Fb_Ptr = NULL;
-  
-  close(fb_fd);
-  fb_fd = -1;
-}
-
 void Fb_clear(void)
 {
   memset(Fb_Ptr, 0, local_info.screenbytes);

src/fbinit.h

@@ -27,7 +27,6 @@ extern PCFBINFO Fb_Info;
 extern UINT16 *Fb_Ptr;
 
 extern HRESULT Fb_setup(void);
-extern void Fb_cleanup(void);
 extern void Fb_clear(void);
 
 #endif /* __FBINIT_H_INCLUDED */

src/gpio.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include <bcm2835.h>
+#include "config.h"
 #include "log.h"
 #include "scode.h"
 #include "gpio.h"
@@ -12,8 +13,31 @@
 
 #define PWM_BACKLIGHT   0
 
+static void do_cleanup(void)
+{
+  /* close down the backlight lines */
+  bcm2835_pwm_set_mode(PWM_BACKLIGHT, 1, 0);
+  bcm2835_gpio_set_pud(GLINE_BACKLIGHT, BCM2835_GPIO_PUD_OFF);
+  bcm2835_gpio_fsel(GLINE_BACKLIGHT, BCM2835_GPIO_FSEL_INPT);
+
+  /* close down the button lines */
+  bcm2835_gpio_set_pud(GLINE_BUTTON1, BCM2835_GPIO_PUD_OFF);
+  bcm2835_gpio_fsel(GLINE_BUTTON1, BCM2835_GPIO_FSEL_INPT);
+  bcm2835_gpio_set_pud(GLINE_BUTTON2, BCM2835_GPIO_PUD_OFF);
+  bcm2835_gpio_fsel(GLINE_BUTTON2, BCM2835_GPIO_FSEL_INPT);
+  bcm2835_gpio_set_pud(GLINE_BUTTON3, BCM2835_GPIO_PUD_OFF);
+  bcm2835_gpio_fsel(GLINE_BUTTON3, BCM2835_GPIO_FSEL_INPT);
+  bcm2835_gpio_set_pud(GLINE_BUTTON4, BCM2835_GPIO_PUD_OFF);
+  bcm2835_gpio_fsel(GLINE_BUTTON4, BCM2835_GPIO_FSEL_INPT);
+
+  if (!bcm2835_close())
+    Log(LWARN, "Closing BCM2835 library failed");
+}
+
 HRESULT Gpio_setup(void)
 {
+  HRESULT hr;
+  
   if (!bcm2835_init())
   {
     Log(LFATAL, "Error initializing BCM2835 library");
@@ -38,28 +62,10 @@ HRESULT Gpio_setup(void)
   bcm2835_pwm_set_range(PWM_BACKLIGHT, GSB_BACKLIGHT_MAX + 1);
   bcm2835_pwm_set_data(PWM_BACKLIGHT, GSB_BACKLIGHT_MAX);
 
-  return S_OK;
+  hr = Config_exitfunc(do_cleanup);
-}
+  if (FAILED(hr))
-
+    do_cleanup();
-void Gpio_cleanup(void)
+  return hr;
-{
-  /* close down the backlight lines */
-  bcm2835_pwm_set_mode(PWM_BACKLIGHT, 1, 0);
-  bcm2835_gpio_set_pud(GLINE_BACKLIGHT, BCM2835_GPIO_PUD_OFF);
-  bcm2835_gpio_fsel(GLINE_BACKLIGHT, BCM2835_GPIO_FSEL_INPT);
-
-  /* close down the button lines */
-  bcm2835_gpio_set_pud(GLINE_BUTTON1, BCM2835_GPIO_PUD_OFF);
-  bcm2835_gpio_fsel(GLINE_BUTTON1, BCM2835_GPIO_FSEL_INPT);
-  bcm2835_gpio_set_pud(GLINE_BUTTON2, BCM2835_GPIO_PUD_OFF);
-  bcm2835_gpio_fsel(GLINE_BUTTON2, BCM2835_GPIO_FSEL_INPT);
-  bcm2835_gpio_set_pud(GLINE_BUTTON3, BCM2835_GPIO_PUD_OFF);
-  bcm2835_gpio_fsel(GLINE_BUTTON3, BCM2835_GPIO_FSEL_INPT);
-  bcm2835_gpio_set_pud(GLINE_BUTTON4, BCM2835_GPIO_PUD_OFF);
-  bcm2835_gpio_fsel(GLINE_BUTTON4, BCM2835_GPIO_FSEL_INPT);
-
-  if (!bcm2835_close())
-    Log(LWARN, "Closing BCM2835 library failed");
 }
 
 UINT32 Gpio_read_buttons(void)

src/gpio.h

@@ -13,7 +13,6 @@
 #define GSB_BACKLIGHT_MAX   1023
 
 extern HRESULT Gpio_setup(void);
-extern void Gpio_cleanup(void);
 extern UINT32 Gpio_read_buttons(void);
 extern void Gpio_set_backlight(UINT32 level);
 

src/main.c

@@ -2,6 +2,7 @@
 #include <string.h>
 #include <unistd.h>
 #include "scode.h"
+#include "config.h"
 #include "gpio.h"
 #include "log.h"
 #include "fbinit.h"
@@ -29,17 +30,16 @@ int main(int argc, char *argv[])
   int running = 1;
   MSG msg;
   char *tmp;
-  
+
   Time_init();
+  if (FAILED(Config_setup()))
+    return EXIT_FAILURE;
   if (FAILED(Fb_setup()))
     return EXIT_FAILURE;
-  atexit(Fb_cleanup);
   if (FAILED(Gpio_setup()))
     return EXIT_FAILURE;
-  atexit(Gpio_cleanup);
   if (FAILED(Sys_enable_input()))
     return EXIT_FAILURE;
-  atexit(Sys_disable_input);
   Log(LINFO, "Pausing at startup.");
   sleep(5); /* wait to show off splash screen */
 

src/msg_queue.c

@@ -56,7 +56,7 @@ void Mq_post(PMSG_QUEUE queue, HANDLE target, UINT32 message, const UINT_PTR *at
   if (nattrs > MSG_ATTRCOUNT)
     nattrs = MSG_ATTRCOUNT;
   if (nattrs > 0)
-    memcpy(&(tmpmsg.attrs), attrs, sizeof(uintptr_t) * nattrs);
+    memcpy(&(tmpmsg.attrs), attrs, sizeof(UINT_PTR) * nattrs);
   tmpmsg.timestamp = Time_since_start();
   post_internal(queue, &tmpmsg);
 }

src/sysinput.c

@@ -8,8 +8,6 @@
 #include "gpio.h"
 #include "time_func.h"
 
-#define DEBOUNCE_BUTTON_MSEC  100
-
 PMSG_QUEUE Sys_Queue = NULL;
 
 static pthread_t ithread;
@@ -40,7 +38,7 @@ static void *input_thread(void *arg)
 	  continue;
 	if (up & mask)
 	{
-	  button_event_ok[attr - 1] = now + DEBOUNCE_BUTTON_MSEC;
+	  button_event_ok[attr - 1] = now + Gconfig.button_debounce;
 	  Mq_post1(Sys_Queue, 0, WM_HWBUTTONUP, attr);
 	}
 	else if (down & mask)
@@ -54,12 +52,20 @@ static void *input_thread(void *arg)
   return NULL;
 }
 
+static void do_disable_input(void)
+{
+  running = 0;
+  pthread_join(ithread, NULL);
+  Mq_destroy(Sys_Queue);
+  Sys_Queue = NULL;
+}
+
 HRESULT Sys_enable_input(void)
 {
   HRESULT rc = S_OK;
   int threadrc;
   
-  Sys_Queue = Mq_alloc(64);
+  Sys_Queue = Mq_alloc(Gconfig.sys_mq_length);
   if (!Sys_Queue)
   {
     Log(LFATAL, "Unable to allocate system message queue.");
@@ -72,13 +78,11 @@ HRESULT Sys_enable_input(void)
     rc = SCODE_FROM_ERRNO(threadrc);
     Log(LFATAL, "Unable to start system input thread (%08X).", rc);
   }
+  if (SUCCEEDED(rc))
+  {
+    rc = Config_exitfunc(do_disable_input);
+    if (FAILED(rc))
+      do_disable_input();
+  }
   return rc;
 }
-
-void Sys_disable_input(void)
-{
-  running = 0;
-  pthread_join(ithread, NULL);
-  Mq_destroy(Sys_Queue);
-  Sys_Queue = NULL;
-}

src/sysinput.h

@@ -7,6 +7,5 @@
 extern PMSG_QUEUE Sys_Queue;
 
 extern HRESULT Sys_enable_input(void);
-extern void Sys_disable_input(void);
 
 #endif /* __SYSINPUT_H_INCLUDED */