1 files changed, 57 insertions, 16 deletions

diff --git a/7_1/main.c b/7_1/main.c
index 0c9ae14..9a38d63 100644
--- a/7_1/main.c
+++ b/7_1/main.c
@@ -1,11 +1,13 @@
-#include<stdlib.h>
-#include<stdio.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
 
+#define LONGMIN 0x8000000000000000
 #define RED "\x1b[91m"
 #define GRN "\x1b[92m"
 #define RST "\x1b[0m"
 
-/* breaks (segfaults) if x = 0x8000000000000000 */
 char* tobin(long int x) {
 	size_t i = 0, j = 0;
 	char buffer[64];
@@ -22,27 +24,66 @@ char* tobin(long int x) {
 	return ret;
 }
 
-int main(int argc, char* argv[]) {
+void handle_main_arg(int argc, char *argv[]) {
 	long number;
 	char *bin;
+	int i;
 	
-	if (argc != 2) {
-		fprintf(stderr, RED "Error: Invalid amount of arguments\n" RST "Usage: " GRN "%s <number>\n" RST , argv[0]);
-		return EXIT_FAILURE;
+	/* Iterate over every argument and print conversions to stdout */
+	for (i = 1; i < argc; ++i) {
+		number = atol(argv[i]);
+
+		/* Since I am negating a number using the branchless trick,
+		 * Multiplying this number by -1 still gives you a negative number because of the overflow 
+		 * Unfortunately this has to be handled separately */
+		if (number == LONGMIN) {
+			fprintf(stderr, RED "Error: " RST "The number %li does not fit in 64 bits\n", number);
+			continue;
+		}
+
+		bin = tobin(number);
+		printf("Binary for %-20li: %s\n", number, bin);
+		free(bin);
 	}
+}
 
-	number = atol(argv[1]);
+int handle_main_noarg(char *filename) {
+	FILE *f;
+	long num, pos, max;
+	char *buf;
 
-	/* Since I am negating a number using the branchless trick,
-	 * Multiplying this number by -1 still gives you a negative number because of the overflow 
-	 * Unfortunately this has to be handled separately */
-	if (number == 0x8000000000000000) {
-		puts(RED "Error: " RST "The number does not fit in 64 bits");
+	f = fopen(filename, "r+");
+	if (!f) {
+		fprintf(stderr, RED "Error: could not open file %s" RST " (errno %i: %s)\n", filename, errno, strerror(errno));
 		return EXIT_FAILURE;
 	}
+	fseek(f, 0, SEEK_END);
+	max = ftell(f);
+	fseek(f, 0, SEEK_SET);
+	while (fscanf(f, "%li", &num) == 1) {
+		if (num == LONGMIN) {
+			fprintf(stderr, RED "Error: " RST "The number %li does not fit in 64 bits\n", num);
+			continue;
+		}
+		pos = ftell(f);			/* Remember position in file */
+		if (pos >= max) break;
+		fseek(f, 0, SEEK_END);		/* Go to end of file */
+		buf = tobin(num);		/* Perform conversion */
+		fprintf(f, "%s\n", buf);	/* Write the conversion there */
+		fseek(f, pos, SEEK_SET);	/* Restore file position*/
+		free(buf);
+	}
+	fclose(f);
+	return EXIT_SUCCESS;
+}
 
-	bin = tobin(number);
-	printf("Binary for %-20li: %s\n", number, bin);
-	free(bin);
+int main(int argc, char* argv[]) {
+	char * filename;
+	if (argc < 2) {
+		fprintf(stderr, RED "Error: Invalid arguments.\n" RST "Usage: " GRN "%s filename" RST " or " GRN "%s num1 num2 num3...\n" RST, *argv, *argv);
+		return EXIT_FAILURE;
+	}
+	if (argc == 2) return handle_main_noarg(argv[1]);
+	handle_main_arg(argc, argv);
 	return EXIT_SUCCESS;
 }