A script to run other programs defined in a configuration file

main.c

//
//
// Works both on windows and linux
//
//

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>

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

#define FILE_CONFIG_NAME	"program-config.txt"

int file_exists(const char* filename){
	struct stat buffer;
	int exist = stat(filename,&buffer);
	if(exist == 0)
		return 1;
	else // -1
		return 0;
}

char file_content_buffer[1024];

char * file_get_contents(const char * filename) {
	FILE *fp;
	fp = fopen(filename, "r");
	int length = fread(file_content_buffer, 1, 1024, fp);
	printf("read %d\n", length);
	fclose(fp);
	return file_content_buffer;
}

#define FILE_CREATE		0
#define FILE_APPEND		1

int file_put_contents(const char * filename, char * buffer, int mode) {
	FILE *fp;
	if (mode == FILE_APPEND) {
		fp = fopen(filename, "a");
	} else {
		fp = fopen(filename, "w");
	}
	int bytes = fputs(buffer, fp);
	fclose(fp);
	return bytes;
}

int for_each_line(char * buffer, void (*callback)(char *)) {
	int i;
	int buffer_index = 0;
	char buffer_line[1024];
	for (i=0;i<1024;i++) {
		//printf("byte %d = %d [%c]\n", i, buffer[i], buffer[i]);
		if (buffer[i] == '\n' || buffer[i] == '\r' || buffer[i] == '\0') {
			buffer_line[buffer_index++] = '\0';
			if (buffer_line[0] != '\0' && buffer_index >= 2) {
				callback(buffer_line);
			}
			buffer_index = 0;
			buffer_line[0] = '\0';
			if (buffer[i] == '\0') {
				break;
			}
		} else {
			buffer_line[buffer_index++] = buffer[i];
		}
	}
}

char sysbuffer[256];

void process_config_line(char * line) {
	int is_windows = 0;

	#ifdef _WIN32
		is_windows = 1;
	#endif

	if (file_exists(line)) {
		if (is_windows) {
			snprintf(sysbuffer, 256, "start %s", line);
		} else {
			snprintf(sysbuffer, 256, "xdg-open %s", line);
		}
		printf("Executing the command \"%s\"\n", sysbuffer);
		system(sysbuffer);
	} else {
		printf("File not found: %s\n", line);
	}
}


int main(int argn, char ** argc) {
	if (!file_exists(FILE_CONFIG_NAME)) {
		printf("Config file not found: " FILE_CONFIG_NAME "\n");
		return 0;
	}
	char * data = file_get_contents(FILE_CONFIG_NAME);
	for_each_line(data, process_config_line);
	return 0;
}