better parameters (in output, not code)

main.c

@@ -46,7 +46,7 @@ int main(int argc, char **argv) {
 		}
 	}
 
-	printf("\n%u trytes\n\n", size);
+	printf("\nfilesize: %u trytes\n\n", size);
 
 
 	// Close the file
@@ -57,31 +57,59 @@ int main(int argc, char **argv) {
 }
 
 int params(int argc, char **argv){
+	//{{{
+	printf("%s\n", *argv);
+	char in = 0;
+	char out = 0;
+	char ret = 1;
 	if (argc > 2) {
 		for (int i = 1 ; i < argc; i++) {
 			if (strcmp("-i", argv[i]) == 0 || strcmp("--input", argv[i]) == 0) {
-				src_asm = fopen(argv[i+1], "r");
+				if (argv[i+1]==NULL) {
+					//empty
+				} else {
+					in = 1;
+					if((src_asm = fopen(argv[i+1],"r"))!=NULL) {
+						//src_asm = fopen(argv[i+1], "r");
 						i=i+1;
+						ret = 0;
+					} else {
+						printf("tasm: file '%s' does not exist \n", argv[i+1]);
+						ret = 1;
+					}
+				}
 			} else if (strcmp("-o", argv[i]) == 0 || strcmp("--output", argv[i]) == 0) {
+				if (argv[i+1]==NULL) {
+					//empty
+				} else {
 					dest_asm = fopen(argv[i+1], "w");
 					i=i+1;
+					out = 1;
+					ret = 0;
+				}
 			} else if (strcmp("-h", argv[i]) == 0 || strcmp("--help", argv[i]) == 0) {
 				printf("Usage: tasm [options] file...\n");
 				printf("Options:\n");
 				printf("-h,--help		Prints this information\n");
 				printf("-i,--input <arg> 	Path of input file\n");
 				printf("-o,--output <arg>	Path of output file\n");
-				return 1; 
 			} else {
 				printf("unknown argument: %s\n", argv[i]);
-				return 1;
 			}
 		}
-	} else {
+	}
+	if (in == 0) {
 		printf("tasm: no input file\n");
-		return 1;
+		ret = 1;
+	} else {
+		if (out == 0) {
+			printf("tasm: no output file, using default: output\n\n");
+			dest_asm = fopen("output", "w");
 		}
-	return 0;
+	}
+
+	return ret;
+	//}}}
 }
 
 void asm_to_hex(char *_asm, int *opcode, int *in0, int *in1, int *out){
@@ -117,7 +145,6 @@ void asm_to_hex(char *_asm, int *opcode, int *in0, int *in1, int *out){
 		t0[i] = tryte[j];
 		j++;
 	}
-	printf("%s\n",t0);
 
 	bin_to_hex(t0, opcode);
 	bin_to_hex(t1, in0);