Shell Programming and Scripting

/* Y o u r   D e s c r i p t i o n                       */
/*                            AppBuilder Photon Code Lib */
/*                                         Version 2.03  */

/* Standard headers */
#include <stdio.h>
#include <unistd.h>

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <fstream>
#include <sstream>

/* Local headers */
#include "ablibs.h"
#include "AppGlobal.h"
#include "abimport.h"
#include "proto.h"
#include "version.h"

#include <sys/stat.h>
#include <sys/reboot.h>

struct stat sb;

using namespace std;

int
Yes( PtWidget_t *widget, ApInfo_t *apinfo, PtCallbackInfo_t *cbinfo )
{
	// find where abc/123/version x is located
	system("find /fs/*/abc/123/*/ > /root/find.txt");

	// only read the first result
	std::string line;
	std::ifstream stream("/root/find.txt");
	getline(stream,line);

	// current version
	int maj = VERSION_MAJOR;
	int min = VERSION_MINOR;
	int pat = VERSION_PATCH;

	// comparing to
	int maj_comp = 0;
	int min_comp = 0;
	int pat_comp = 0;

	// check if it is a valid folder
	if (stat(line.c_str(), &sb) == 0 && S_ISDIR(sb.st_mode))
	{
		unsigned found = line.find_last_of("/");

		stringstream line_to_int;
		line_to_int << line[found-5];
		line_to_int >> maj_comp;

		line_to_int.str("");
		line_to_int << line[found-3];
		line_to_int >> min_comp;

		line_to_int.str("");
		line_to_int << line[found-1];
		line_to_int >> pat_comp;

		//if ((maj_comp == maj) || ( min_comp == min) || ( pat_comp == pat))
		if ((maj_comp != maj) || ( min_comp != min) || ( pat_comp != pat))
		{
			std::ofstream installation("/root/upgrade.sh");

			if (installation.is_open())
			{
				installation  << "#!/bin/sh\n";
				//installation  << "su -c \n";
				installation  << "cd " << line <<"\n";
				installation  << "sh ./install\n";
				//installation  << "shutdown";
				installation.close();
			}

			system("chmod 777 /root/upgrade.sh");
			system("/root/upgrade.sh");

		}
		else
		{
			cout << "current version is up to date" << endl;
		}

	}

	// check path if it exist if it does check
	// if current version is greater than upgrade
	// perform upgrade

	// else display error message cannot find file
	// check if usb is properly connected
	// check if path is valid


	/* eliminate 'unreferenced' warnings */
	widget = widget, apinfo = apinfo, cbinfo = cbinfo;

	return( Pt_CONTINUE );

}

su -c "cd whatever ; sh ./installation"

char buf[1024], *b;
FILE *p=popen("echo /fs/*/abc/123/*/", "r");
fgets(buf, 1024, p);
pclose(p);

// Find last /
b=strchr(buf, '/');
while(strchr(buf, '/')) b=strchr(b, '/');

// Check for filename like /0.1.2.... and read into ..._comp variables
if(sscanf(b, "/%d.%d.%d", &maj_comp, &min_comp, &patch_comp) == 3)
{
        ...
}