Change to new GCD function

main.c

@@ -111,13 +111,12 @@ static void print_arg_error(const char *arg);
 static void print_help_and_exit(void);
 static void print_version_and_exit(void);
 static void print_info_and_exit(void);
-static unsigned long find_gcf(unsigned long *nums, size_t len);
-static unsigned long *find_prime_factors(unsigned long n, size_t *out_len);
 static void initialize_modules(void);
+static unsigned long gcd(unsigned long n1, unsigned long n2);
+static unsigned long find_module_refresh_time(void);
 static void set_refresh_time(void);
 static void signal_handler(int signum);
 static void setup_signals(void);
-static unsigned long find_module_refresh_gcf(void);
 static unsigned long timespec_to_miliseconds(struct timespec *ts);
 static void miliseconds_to_timespec(unsigned long ms, struct timespec *out_ts);
 static void do_initial_refresh(void);
@@ -431,102 +430,6 @@ static void print_info_and_exit(void) {
     qtb_exit();
 }
 
-static unsigned long find_gcf(unsigned long *nums, size_t len) {
-    if (len == 0) { /* gcf(0) = 0 */
-        return 0;
-    } else if (len == 1) { /* gcf(n) = n */
-        return nums[0];
-    }
-    /* calculate all prime factors */
-    unsigned long **prime_factors = NULL;
-    size_t prime_factors_length = 0;
-    size_t i;
-    for (i = 0; i < len; ++i) {
-        unsigned long *i_prime_factors = find_prime_factors(nums[i], NULL);
-        prime_factors = qtb_realloc(prime_factors, sizeof(unsigned long *) *
-                                                       ++prime_factors_length);
-        prime_factors[prime_factors_length - 1] = i_prime_factors;
-    }
-    /* find which calculated prime factors are common to all inputs */
-    unsigned long *common_factors = NULL;
-    size_t common_factors_length = 0;
-    unsigned long *j;
-    /* loop though each factor in prime_factors[0] */
-    for (j = prime_factors[0]; *j != 0; ++j) {
-        /* loop though every set of factors except prime_factors[0] */
-        /* size_t i; */
-        for (i = 1; i < prime_factors_length; ++i) {
-            unsigned long *i_prime_factors;
-            for (i_prime_factors = prime_factors[i]; *i_prime_factors != 0;
-                 ++i_prime_factors) {
-                if (*i_prime_factors == *j) {
-                    *i_prime_factors = 4; /* remove the factor (by setting it to
-                                             a composite number) */
-                    goto found_factor;
-                }
-            }
-            /* the factor was not found, therefore we can't add it */
-            goto dont_add;
-            /* we found the factor, check the next set of factors */
-        found_factor:
-            continue;
-        }
-        /* the factor was a common factor, add it */
-        common_factors = qtb_realloc(
-            common_factors, sizeof(unsigned long) * ++common_factors_length);
-        common_factors[common_factors_length - 1] = *j;
-        /* the factor was not a common factor */
-    dont_add:
-        continue;
-    }
-    /* qtb_free sets of factors */
-    /* size_t i; */
-    for (i = 0; i < prime_factors_length; ++i) {
-        qtb_free(prime_factors[i]);
-    }
-    qtb_free(prime_factors);
-    /* finally, calculate the gcf */
-    unsigned long gcf = 1;
-    /* size_t i; */
-    for (i = 0; i < common_factors_length; ++i) {
-        gcf *= common_factors[i];
-    }
-    qtb_free(common_factors);
-    return gcf;
-}
-
-/* return value will be 0 terminated. if out_len is not NULL,
-   it's value will be set to the number of primes found (length of return value
-   - 1) */
-static unsigned long *find_prime_factors(unsigned long n, size_t *out_len) {
-    unsigned long *out_arr = NULL;
-    size_t arr_len = 0;
-    while (n % 2 == 0) {
-        out_arr = qtb_realloc(out_arr, sizeof(unsigned long) * ++arr_len);
-        out_arr[arr_len - 1] = 2;
-        n /= 2;
-    }
-    unsigned long i;
-    for (i = 3; i <= sqrtl(n); i += 2) {
-        while (n % i == 0) {
-            out_arr =
-                qtb_realloc(out_arr, sizeof(unsigned long) * ++arr_len);
-            out_arr[arr_len - 1] = i;
-            n /= i;
-        }
-    }
-    if (n > 2) {
-        out_arr = qtb_realloc(out_arr, sizeof(unsigned long) * ++arr_len);
-        out_arr[arr_len - 1] = n;
-    }
-    out_arr = qtb_realloc(out_arr, sizeof(unsigned long) * arr_len);
-    out_arr[arr_len] = 0;
-    if (out_len) {
-        *out_len = arr_len;
-    }
-    return out_arr;
-}
-
 static void initialize_modules() {
     int has_error = FALSE;
     size_t i;
@@ -552,11 +455,42 @@ static void initialize_modules() {
     }
 }
 
+unsigned long gcd(unsigned long n1, unsigned long n2) {
+    if (n1 == 0) {
+        return n2;
+    }
+    return gcd(n2 % n1, n1);
+}
+
+unsigned long find_module_refresh_time() {
+    size_t i;
+    size_t ignore_index;
+    size_t result;
+    for (i = 0; i < global_module_count; ++i) {
+        if (!modules[i].disabled && modules[i].refresh_time != NO_REFRESH) {
+            result = modules[i].refresh_time;
+            ignore_index = i;
+        }
+    }
+    for (i = 0; i < global_module_count; ++i) {
+        if (i == ignore_index) {
+            continue;
+        }
+        if (!modules[i].disabled && modules[i].refresh_time != NO_REFRESH) {
+            result = gcd(result, modules[i].refresh_time);
+        }
+        if (result == 1) {
+            break;
+        }
+    }
+    return result;
+}
+
 static void set_refresh_time() {
 #ifdef REFRESH_TIME
     unsigned long refresh_ms = REFRESH_TIME;
 #else
-    unsigned long refresh_ms = find_module_refresh_gcf();
+    unsigned long refresh_ms = find_module_refresh_time();
     if (refresh_ms == 0) {     /* if all modules are triggered by signals */
         refresh_ms = HOURS(1); /* refresh once an hour */
     }
@@ -600,22 +534,6 @@ static void setup_signals() {
     sigprocmask(SIG_BLOCK, &global_real_time_mask, NULL);
 }
 
-static unsigned long find_module_refresh_gcf() {
-    size_t refresh_times_length = 0;
-    unsigned long *refresh_times = NULL;
-    size_t i;
-    for (i = 0; i < global_module_count; ++i) {
-        if (!modules[i].disabled && modules[i].refresh_time != NO_REFRESH) {
-            refresh_times = qtb_realloc(
-                refresh_times, sizeof(unsigned long) * ++refresh_times_length);
-            refresh_times[refresh_times_length - 1] = modules[i].refresh_time;
-        }
-    }
-    unsigned long gcf = find_gcf(refresh_times, refresh_times_length);
-    qtb_free(refresh_times);
-    return gcf;
-}
-
 static unsigned long timespec_to_miliseconds(struct timespec *ts) {
     return (ts->tv_sec * 1000) + (ts->tv_nsec / 1000000);
 }