Initial move to GIT
diff --git a/gpio/gpio.c b/gpio/gpio.c
new file mode 100644
index 0000000..54dfbc3
--- /dev/null
+++ b/gpio/gpio.c
@@ -0,0 +1,755 @@
+/*
+ * gpio.c:
+ *	Set-UID command-line interface to the Raspberry Pi's GPIO
+ *	Copyright (c) 2012 Gordon Henderson
+ ***********************************************************************
+ * This file is part of wiringPi:
+ *	https://projects.drogon.net/raspberry-pi/wiringpi/
+ *
+ *    wiringPi is free software: you can redistribute it and/or modify
+ *    it under the terms of the GNU Lesser General Public License as published by
+ *    the Free Software Foundation, either version 3 of the License, or
+ *    (at your option) any later version.
+ *
+ *    wiringPi is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Lesser General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Lesser General Public License
+ *    along with wiringPi.  If not, see <http://www.gnu.org/licenses/>.
+ ***********************************************************************
+ */
+
+#include <wiringPi.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <fcntl.h>
+
+#ifndef TRUE
+#  define	TRUE	(1==1)
+#  define	FALSE	(1==2)
+#endif
+
+#define	VERSION	"1.1"
+
+static int wpMode ;
+
+char *usage = "Usage: gpio -v\n"
+              "       gpio [-g] <read/write/pwm/mode> ...\n"
+              "       gpio [-p] <read/write/mode> ...\n"
+	      "       gpio export/edge/unexport/unexportall/exports ...\n"
+	      "       gpio drive <group> <value>\n"
+	      "       gpio load spi/i2c" ;
+
+
+
+/*
+ * changeOwner:
+ *	Change the ownership of the file to the real userId of the calling
+ *	program so we can access it.
+ *********************************************************************************
+ */
+
+static void changeOwner (char *cmd, char *file)
+{
+  uid_t uid = getuid () ;
+  uid_t gid = getgid () ;
+
+  if (chown (file, uid, gid) != 0)
+  {
+    if (errno == ENOENT)	// Warn that it's not there
+      fprintf (stderr, "%s: Warning: File not present: %s\n", cmd, file) ;
+    else
+    {
+      fprintf (stderr, "%s: Unable to change ownership of %s: %s\n", cmd, file, strerror (errno)) ;
+      exit (1) ;
+    }
+  }
+}
+
+
+/*
+ * moduleLoaded:
+ *	Return true/false if the supplied module is loaded
+ *********************************************************************************
+ */
+
+static int moduleLoaded (char *modName)
+{
+  int len   = strlen (modName) ;
+  int found = FALSE ;
+  FILE *fd = fopen ("/proc/modules", "r") ;
+  char line [80] ;
+
+  if (fd == NULL)
+  {
+    fprintf (stderr, "gpio: Unable to check modules: %s\n", strerror (errno)) ;
+    exit (1) ;
+  }
+
+  while (fgets (line, 80, fd) != NULL)
+  {
+    if (strncmp (line, modName, len) != 0)
+      continue ;
+
+    found = TRUE ;
+    break ;
+  }
+
+  fclose (fd) ;
+
+  return found ;
+}
+
+
+/*
+ * doLoad:
+ *	Load either the spi or i2c modules and change device ownerships, etc.
+ *********************************************************************************
+ */
+
+static void _doLoadUsage (char *argv [])
+{
+  fprintf (stderr, "Usage: %s load <spi/i2c>\n", argv [0]) ;
+  exit (1) ;
+}
+
+static void doLoad (int argc, char *argv [])
+{
+  char *module ;
+  char cmd [80] ;
+  char *file1, *file2 ;
+
+  if (argc != 3)
+    _doLoadUsage (argv) ;
+
+  /**/ if (strcasecmp (argv [2], "spi") == 0)
+  {
+    module = "spi_bcm2708" ;
+    file1  = "/dev/spidev0.0" ;
+    file2  = "/dev/spidev0.1" ;
+  }
+  else if (strcasecmp (argv [2], "i2c") == 0)
+  {
+    module = "i2c_bcm2708" ;
+    file1  = "/dev/i2c-0" ;
+    file2  = "/dev/i2c-1" ;
+  }
+  else
+    _doLoadUsage (argv) ;
+
+  if (!moduleLoaded (module))
+  {
+    sprintf (cmd, "modprobe %s", module) ;
+    system (cmd) ;
+  }
+
+  if (!moduleLoaded (module))
+  {
+    fprintf (stderr, "%s: Unable to load %s\n", argv [0], module) ;
+    exit (1) ;
+  }
+
+  sleep (1) ;	// To let things get settled
+
+  changeOwner (argv [0], file1) ;
+  changeOwner (argv [0], file2) ;
+}
+
+
+
+/*
+ * doExports:
+ *	List all GPIO exports
+ *********************************************************************************
+ */
+
+void doExports (void)
+{
+  int fd ;
+  int i, l, first ;
+  char fName [128] ;
+  char buf [16] ;
+
+// Rather crude, but who knows what others are up to...
+
+  for (first = 0, i = 0 ; i < 64 ; ++i)
+  {
+
+// Try to read the direction
+
+    sprintf (fName, "/sys/class/gpio/gpio%d/direction", i) ;
+    if ((fd = open (fName, O_RDONLY)) == -1)
+      continue ;
+
+    if (first == 0)
+    {
+      ++first ;
+      printf ("GPIO Pins exported:\n") ;
+    }
+
+    printf ("%4d: ", i) ;
+
+    if ((l = read (fd, buf, 16)) == 0)
+      sprintf (buf, "%s", "?") ;
+ 
+    buf [l] = 0 ;
+    if ((buf [strlen (buf) - 1]) == '\n')
+      buf [strlen (buf) - 1] = 0 ;
+
+    printf ("%-3s", buf) ;
+
+    close (fd) ;
+
+// Try to Read the value
+
+    sprintf (fName, "/sys/class/gpio/gpio%d/value", i) ;
+    if ((fd = open (fName, O_RDONLY)) == -1)
+    {
+      printf ("No Value file (huh?)\n") ;
+      continue ;
+    }
+
+    if ((l = read (fd, buf, 16)) == 0)
+      sprintf (buf, "%s", "?") ;
+
+    buf [l] = 0 ;
+    if ((buf [strlen (buf) - 1]) == '\n')
+      buf [strlen (buf) - 1] = 0 ;
+
+    printf ("  %s", buf) ;
+
+// Read any edge trigger file
+
+    sprintf (fName, "/sys/class/gpio/gpio%d/edge", i) ;
+    if ((fd = open (fName, O_RDONLY)) == -1)
+    {
+      printf ("\n") ;
+      continue ;
+    }
+
+    if ((l = read (fd, buf, 16)) == 0)
+      sprintf (buf, "%s", "?") ;
+
+    buf [l] = 0 ;
+    if ((buf [strlen (buf) - 1]) == '\n')
+      buf [strlen (buf) - 1] = 0 ;
+
+    printf ("  %-8s\n", buf) ;
+
+    close (fd) ;
+  }
+}
+
+
+/*
+ * doExport:
+ *	gpio export pin mode
+ *	This uses the /sys/class/gpio device interface.
+ *********************************************************************************
+ */
+
+void doExport (int argc, char *argv [])
+{
+  FILE *fd ;
+  int pin ;
+  char *mode ;
+  char fName [128] ;
+
+  if (argc != 4)
+  {
+    fprintf (stderr, "Usage: %s export pin mode\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  pin = atoi (argv [2]) ;
+
+  mode = argv [3] ;
+
+  if ((fd = fopen ("/sys/class/gpio/export", "w")) == NULL)
+  {
+    fprintf (stderr, "%s: Unable to open GPIO export interface: %s\n", argv [0], strerror (errno)) ;
+    exit (1) ;
+  }
+
+  fprintf (fd, "%d\n", pin) ;
+  fclose (fd) ;
+
+  sprintf (fName, "/sys/class/gpio/gpio%d/direction", pin) ;
+  if ((fd = fopen (fName, "w")) == NULL)
+  {
+    fprintf (stderr, "%s: Unable to open GPIO direction interface for pin %d: %s\n", argv [0], pin, strerror (errno)) ;
+    exit (1) ;
+  }
+
+  /**/ if ((strcasecmp (mode, "in")  == 0) || (strcasecmp (mode, "input")  == 0))
+    fprintf (fd, "in\n") ;
+  else if ((strcasecmp (mode, "out") == 0) || (strcasecmp (mode, "output") == 0))
+    fprintf (fd, "out\n") ;
+  else
+  {
+    fprintf (stderr, "%s: Invalid mode: %s. Should be in or out\n", argv [1], mode) ;
+    exit (1) ;
+  }
+
+  fclose (fd) ;
+
+// Change ownership so the current user can actually use it!
+
+  sprintf (fName, "/sys/class/gpio/gpio%d/value", pin) ;
+  changeOwner (argv [0], fName) ;
+
+  sprintf (fName, "/sys/class/gpio/gpio%d/edge", pin) ;
+  changeOwner (argv [0], fName) ;
+
+}
+
+
+/*
+ * doEdge:
+ *	gpio edge pin mode
+ *	Easy access to changing the edge trigger on a GPIO pin
+ *	This uses the /sys/class/gpio device interface.
+ *********************************************************************************
+ */
+
+void doEdge (int argc, char *argv [])
+{
+  FILE *fd ;
+  int pin ;
+  char *mode ;
+  char fName [128] ;
+  uid_t uid ;
+  gid_t gid ;
+
+  if (argc != 4)
+  {
+    fprintf (stderr, "Usage: %s edge pin mode\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  pin = atoi (argv [2]) ;
+
+  mode = argv [3] ;
+
+// Export the pin and set direction to input
+
+  if ((fd = fopen ("/sys/class/gpio/export", "w")) == NULL)
+  {
+    fprintf (stderr, "%s: Unable to open GPIO export interface: %s\n", argv [0], strerror (errno)) ;
+    exit (1) ;
+  }
+
+  fprintf (fd, "%d\n", pin) ;
+  fclose (fd) ;
+
+  sprintf (fName, "/sys/class/gpio/gpio%d/direction", pin) ;
+  if ((fd = fopen (fName, "w")) == NULL)
+  {
+    fprintf (stderr, "%s: Unable to open GPIO direction interface for pin %d: %s\n", argv [0], pin, strerror (errno)) ;
+    exit (1) ;
+  }
+
+  fprintf (fd, "in\n") ;
+  fclose (fd) ;
+
+  sprintf (fName, "/sys/class/gpio/gpio%d/edge", pin) ;
+  if ((fd = fopen (fName, "w")) == NULL)
+  {
+    fprintf (stderr, "%s: Unable to open GPIO edge interface for pin %d: %s\n", argv [0], pin, strerror (errno)) ;
+    exit (1) ;
+  }
+
+  /**/ if (strcasecmp (mode, "none")    == 0)
+    fprintf (fd, "none\n") ;
+  else if (strcasecmp (mode, "rising")  == 0)
+    fprintf (fd, "rising\n") ;
+  else if (strcasecmp (mode, "falling") == 0)
+    fprintf (fd, "falling\n") ;
+  else if (strcasecmp (mode, "both")    == 0)
+    fprintf (fd, "both\n") ;
+  else
+  {
+    fprintf (stderr, "%s: Invalid mode: %s. Should be none, rising, falling or both\n", argv [1], mode) ;
+    exit (1) ;
+  }
+
+// Change ownership so the current user can actually use it!
+
+  uid = getuid () ;
+  gid = getgid () ;
+
+  sprintf (fName, "/sys/class/gpio/gpio%d/value", pin) ;
+  if (chown (fName, uid, gid) != 0)
+  {
+    fprintf (stderr, "%s: Unable to change ownership of the value file: %s\n", argv [1], strerror (errno)) ;
+    exit (1) ;
+  }
+
+// Also change ownership of the edge file
+
+  sprintf (fName, "/sys/class/gpio/gpio%d/edge", pin) ;
+  if (chown (fName, uid, gid) != 0)
+  {
+    fprintf (stderr, "%s: Unable to change ownership of the value file: %s\n", argv [1], strerror (errno)) ;
+    exit (1) ;
+  }
+
+  fclose (fd) ;
+}
+
+
+/*
+ * doUnexport:
+ *	gpio unexport pin
+ *	This uses the /sys/class/gpio device interface.
+ *********************************************************************************
+ */
+
+void doUnexport (int argc, char *argv [])
+{
+  FILE *fd ;
+  int pin ;
+
+  if (argc != 3)
+  {
+    fprintf (stderr, "Usage: %s unexport pin\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  pin = atoi (argv [2]) ;
+
+  if ((fd = fopen ("/sys/class/gpio/unexport", "w")) == NULL)
+  {
+    fprintf (stderr, "%s: Unable to open GPIO export interface\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  fprintf (fd, "%d\n", pin) ;
+  fclose (fd) ;
+}
+
+
+/*
+ * doUnexportAll:
+ *	gpio unexportall
+ *	Un-Export all the GPIO pins.
+ *	This uses the /sys/class/gpio device interface.
+ *********************************************************************************
+ */
+
+void doUnexportall (int argc, char *argv [])
+{
+  FILE *fd ;
+  int pin ;
+
+  for (pin = 0 ; pin < 63 ; ++pin)
+  {
+    if ((fd = fopen ("/sys/class/gpio/unexport", "w")) == NULL)
+    {
+      fprintf (stderr, "%s: Unable to open GPIO export interface\n", argv [0]) ;
+      exit (1) ;
+    }
+    fprintf (fd, "%d\n", pin) ;
+    fclose (fd) ;
+  }
+}
+
+
+/*
+ * doMode:
+ *	gpio mode pin mode ...
+ *********************************************************************************
+ */
+
+void doMode (int argc, char *argv [])
+{
+  int pin ;
+  char *mode ;
+
+  if (argc != 4)
+  {
+    fprintf (stderr, "Usage: %s mode pin mode\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  pin = atoi (argv [2]) ;
+
+  if ((wpMode == WPI_MODE_PINS) && ((pin < 0) || (pin >= NUM_PINS)))
+    return ;
+
+  mode = argv [3] ;
+
+  /**/ if (strcasecmp (mode, "in")   == 0)
+    pinMode (pin, INPUT) ;
+  else if (strcasecmp (mode, "out")  == 0)
+    pinMode (pin, OUTPUT) ;
+  else if (strcasecmp (mode, "pwm")  == 0)
+    pinMode (pin, PWM_OUTPUT) ;
+  else if (strcasecmp (mode, "up")   == 0)
+    pullUpDnControl (pin, PUD_UP) ;
+  else if (strcasecmp (mode, "down") == 0)
+    pullUpDnControl (pin, PUD_DOWN) ;
+  else if (strcasecmp (mode, "tri") == 0)
+    pullUpDnControl (pin, PUD_OFF) ;
+  else
+  {
+    fprintf (stderr, "%s: Invalid mode: %s. Should be in/out/pwm/up/down/tri\n", argv [1], mode) ;
+    exit (1) ;
+  }
+}
+
+
+/*
+ * doPadDrive:
+ *	gpio drive group value
+ *********************************************************************************
+ */
+
+void doPadDrive (int argc, char *argv [])
+{
+  int group, val ;
+
+  if (argc != 4)
+  {
+    fprintf (stderr, "Usage: %s drive group value\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  group = atoi (argv [2]) ;
+  val   = atoi (argv [3]) ;
+
+  if ((group < 0) || (group > 2))
+  {
+    fprintf (stderr, "%s: drive group not 0, 1 or 2: %d\n", argv [0], group) ;
+    exit (1) ;
+  }
+
+  if ((val < 0) || (val > 7))
+  {
+    fprintf (stderr, "%s: drive value not 0-7: %d\n", argv [0], val) ;
+    exit (1) ;
+  }
+
+  setPadDrive (group, val) ;
+}
+
+
+/*
+ * doWrite:
+ *	gpio write pin value
+ *********************************************************************************
+ */
+
+void doWrite (int argc, char *argv [])
+{
+  int pin, val ;
+
+  if (argc != 4)
+  {
+    fprintf (stderr, "Usage: %s write pin value\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  pin = atoi (argv [2]) ;
+
+  if ((wpMode == WPI_MODE_PINS) && ((pin < 0) || (pin >= NUM_PINS)))
+    return ;
+
+  val = atoi (argv [3]) ;
+
+  /**/ if (val == 0)
+    digitalWrite (pin, LOW) ;
+  else
+    digitalWrite (pin, HIGH) ;
+}
+
+
+/*
+ * doRead:
+ *	Read a pin and return the value
+ *********************************************************************************
+ */
+
+void doRead (int argc, char *argv []) 
+{
+  int pin, val ;
+
+  if (argc != 3)
+  {
+    fprintf (stderr, "Usage: %s read pin\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  pin = atoi (argv [2]) ;
+
+  if ((wpMode == WPI_MODE_PINS) && ((pin < 0) || (pin >= NUM_PINS)))
+  {
+    printf ("0\n") ;
+    return ;
+  }
+
+  val = digitalRead (pin) ;
+
+  printf ("%s\n", val == 0 ? "0" : "1") ;
+}
+
+
+/*
+ * doPwm:
+ *	Output a PWM value on a pin
+ *********************************************************************************
+ */
+
+void doPwm (int argc, char *argv [])
+{
+  int pin, val ;
+
+  if (argc != 4)
+  {
+    fprintf (stderr, "Usage: %s pwm <pin> <value>\n", argv [0]) ;
+    exit (1) ;
+  }
+
+  pin = atoi (argv [2]) ;
+
+  if ((wpMode == WPI_MODE_PINS) && ((pin < 0) || (pin >= NUM_PINS)))
+    return ;
+
+  val = atoi (argv [3]) ;
+
+  pwmWrite (pin, val) ;
+}
+
+
+/*
+ * main:
+ *	Start here
+ *********************************************************************************
+ */
+
+int main (int argc, char *argv [])
+{
+  int i ;
+
+  if (argc == 1)
+  {
+    fprintf (stderr, "%s: %s\n", argv [0], usage) ;
+    return 1 ;
+  }
+
+  if (strcasecmp (argv [1], "-v") == 0)
+  {
+    printf ("gpio version: %s\n", VERSION) ;
+    printf ("Copyright (c) 2012 Gordon Henderson\n") ;
+    printf ("This is free software with ABSOLUTELY NO WARRANTY.\n") ;
+    printf ("For details type: %s -warranty\n", argv [0]) ;
+    return 0 ;
+  }
+
+  if (strcasecmp (argv [1], "-warranty") == 0)
+  {
+    printf ("gpio version: %s\n", VERSION) ;
+    printf ("Copyright (c) 2012 Gordon Henderson\n") ;
+    printf ("\n") ;
+    printf ("    This program is free software; you can redistribute it and/or modify\n") ;
+    printf ("    it under the terms of the GNU Leser General Public License as published\n") ;
+    printf ("    by the Free Software Foundation, either version 3 of the License, or\n") ;
+    printf ("    (at your option) any later version.\n") ;
+    printf ("\n") ;
+    printf ("    This program is distributed in the hope that it will be useful,\n") ;
+    printf ("    but WITHOUT ANY WARRANTY; without even the implied warranty of\n") ;
+    printf ("    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n") ;
+    printf ("    GNU Lesser General Public License for more details.\n") ;
+    printf ("\n") ;
+    printf ("    You should have received a copy of the GNU Lesser General Public License\n") ;
+    printf ("    along with this program. If not, see <http://www.gnu.org/licenses/>.\n") ;
+    printf ("\n") ;
+    return 0 ;
+  }
+
+  if (geteuid () != 0)
+  {
+    fprintf (stderr, "%s: Must be root to run. Program should be suid root. This is an error.\n", argv [0]) ;
+    return 1 ;
+  }
+
+// Initial test for /sys/class/gpio operations:
+
+  /**/ if (strcasecmp (argv [1], "exports"    ) == 0)	{ doExports () ;		return 0 ; }
+  else if (strcasecmp (argv [1], "export"     ) == 0)	{ doExport (argc, argv) ;	return 0 ; }
+  else if (strcasecmp (argv [1], "edge"       ) == 0)	{ doEdge (argc, argv) ;		return 0 ; }
+  else if (strcasecmp (argv [1], "unexportall") == 0)	{ doUnexportall (argc, argv) ;	return 0 ; }
+  else if (strcasecmp (argv [1], "unexport"   ) == 0)	{ doUnexport (argc, argv) ;	return 0 ; }
+  else if (strcasecmp (argv [1], "load"       ) == 0)	{ doLoad (argc, argv) ;		return 0 ; }
+
+// Check for -g argument
+
+  if (strcasecmp (argv [1], "-g") == 0)
+  {
+    if (wiringPiSetupGpio () == -1)
+    {
+      fprintf (stderr, "%s: Unable to initialise GPIO in GPIO mode.\n", argv [0]) ;
+      exit (1) ;
+    }
+
+    for (i = 2 ; i < argc ; ++i)
+      argv [i - 1] = argv [i] ;
+    --argc ;
+    wpMode = WPI_MODE_GPIO ;
+  }
+
+// Check for -p argument for PiFace
+
+  else if (strcasecmp (argv [1], "-p") == 0)
+  {
+    if (wiringPiSetupPiFaceForGpioProg () == -1)
+    {
+      fprintf (stderr, "%s: Unable to initialise PiFace.\n", argv [0]) ;
+      exit (1) ;
+    }
+
+    for (i = 2 ; i < argc ; ++i)
+      argv [i - 1] = argv [i] ;
+    --argc ;
+    wpMode = WPI_MODE_PIFACE ;
+  }
+
+// Default to wiringPi mode
+
+  else
+  {
+    if (wiringPiSetup () == -1)
+    {
+      fprintf (stderr, "%s: Unable to initialise GPIO in wiringPi mode\n", argv [0]) ;
+      exit (1) ;
+    }
+    wpMode = WPI_MODE_PINS ;
+  }
+
+// Check for wiring commands
+
+  /**/ if (strcasecmp (argv [1], "write"   ) == 0)
+    doWrite  (argc, argv) ;
+  else if (strcasecmp (argv [1], "read"    ) == 0)
+    doRead   (argc, argv) ;
+  else if (strcasecmp (argv [1], "mode"    ) == 0)
+    doMode   (argc, argv) ;
+  else if (strcasecmp (argv [1], "pwm"     ) == 0)
+    doPwm    (argc, argv) ;
+  else if (strcasecmp (argv [1], "drive"   ) == 0)
+    doPadDrive (argc, argv) ;
+  else
+  {
+    fprintf (stderr, "%s: Unknown command: %s. (read/write/pwm/mode/drive expected)\n", argv [0], argv [1]) ;
+    exit (1) ;
+  }
+  return 0 ;
+}