added return values to indicate failure

diff --git a/main.c b/main.c
index 0c57be3a9e9a61fe49727d7d05a0dd03e038b92d..e49de860dee6848eead291f61d08d08bdab7c1ec 100644 (file)
--- a/main.c
+++ b/main.c
@@ -34,8 +34,8 @@ size_t highestOneBitPosition(unsigned long long a);
 int multiplication_is_safe(unsigned long long a, unsigned long long b);
 int addition_is_safe(unsigned long long a, unsigned long long b);
 
-void do_encode (FILE* in, FILE* out, int wrap_column, int test_only);
-void do_decode (FILE* in, FILE* out, int ignore_garbage);
+int do_encode (FILE* in, FILE* out, int wrap_column, int test_only);
+int do_decode (FILE* in, FILE* out, int ignore_garbage);
 
 
 int main (int argc, char** argv) {
@@ -68,40 +68,41 @@ int main (int argc, char** argv) {
                        op.f = fopen (argv[optind], "rb");
        }
 
+       int retval;
        if (op.d) {
-               do_decode (op.f, stdout, op.i);
+               retval = do_decode (op.f, stdout, op.i);
        } else {
-               do_encode (op.f, stdout, op.w, op.t);
+               retval = do_encode (op.f, stdout, op.w, op.t);
        }
 
-       if (op.f != stdin) fclose (op.f);
+       if (op.f != stdin) retval = !(fclose (op.f) == 0);
 
-       return 0;
+       return retval;
 }
 
 
 
 
-void do_encode (FILE* in, FILE* out, int wrap_column, int test_only) {
+int do_encode (FILE* in, FILE* out, int wrap_column, int test_only) {
        int in_len = 0;
        unsigned long long out_len = 0;
 
        for (int in_char; (in_char = getc(in)) != EOF; in_len++) {
                if (!multiplication_is_safe (out_len, BASE)){
-                       puts ("overflowed.");
-                       return;
+                       fputs ("overflowed.", stderr);
+                       return 1;
                }
                out_len *= BASE;
                if (!addition_is_safe (out_len, in_char)) {
-                       puts ("overflowed.");
-                       return;
+                       fputs ("overflowed.", stderr);
+                       return 1;
                }
                out_len += in_char;
        }
 
        if (test_only) {
                printf ("Length of output:\t%llu\nMaximum value of ULL:\t%llu\n", out_len, ULLONG_MAX);
-               return;
+               return 0;
        }
 
        unsigned long long block_size = 1;
@@ -114,9 +115,11 @@ void do_encode (FILE* in, FILE* out, int wrap_column, int test_only) {
        for (unsigned long long i = 0; i < out_len; i++)
                fprintf (out, "%s%c", wrap_column&&!(i%wrap_column)&&i?"\n":"", 'A');
                //TODO: use faster function
+
+       return 0;
 }
 
-void do_decode (FILE* in, FILE* out, int ignore_garbage) {
+int do_decode (FILE* in, FILE* out, int ignore_garbage) {
        unsigned long long in_len = 0;
 
        for (int in_char; (in_char = getc (in)) != EOF;) {
@@ -126,7 +129,7 @@ void do_decode (FILE* in, FILE* out, int ignore_garbage) {
                        in_len++;
                } else if (!ignore_garbage) {
                        fprintf (stderr, "Unrecognized glyph %c\n", in_char);
-                       return;
+                       return 1;
                }
                // TODO: check for overflow!
        }
@@ -149,6 +152,8 @@ void do_decode (FILE* in, FILE* out, int ignore_garbage) {
        }
 
        for (int i = 0; i < bin_len; i++) putc (out_buf[i], out);
+
+       return 0;
 }
 
 /* http://stackoverflow.com/a/199455 */