Argument parsing!

If it's equal to half then we want to check if it's divisible, since if
it's half then it is NOT prime.

.gitignore

@@ -2,5 +2,8 @@
 build/*
 !build/.keep
 
+# Ignore documentation
+doc/
+
 # Ignore vim temporary files
 *.sw[a-z]

.gitlab-ci.yml

@@ -17,4 +17,4 @@ build:
     # Cache .o files for faster compiling
     cache:
         paths:
-            - "*.o"
+            - "build/CMakeFiles/indivisible.dir/src/*.o"

CHANGELOG

@@ -9,3 +9,17 @@ Change Log
 	- Switch to C.
 	- Uses GNU Multiple Precision library (GMP) to hold prime numbers, allowing for 'infinite' size.
 	- Add `likely()' and `unlikely()' macros to optimize.
+- v0.2.1: Memory Leak Fixes
+	- Fixed a major memory leak at the end of the program.
+	- Added more optimizers.
+- v0.3: Optimizations
+	- Algorithm skips half the known primes.
+	- Removed `likely()' and `unlikely()' macros due to lack of information.
+	- Improved performance.
+- v0.4: Fixed Algorithm
+	- Fixed algorithm to actually calculate primes.
+	- Added extra C99 optimizations.
+- v0.5: Minor Changes
+	- Use `size_t' instead of `unsigned long long int'.
+	- Minor optimizations to the algorithm.
+	- Added commandline argument parsing.

src/list.c

@@ -2,15 +2,12 @@
 #include <stdlib.h>
 #include <stdio.h>
 
-#include "optimizers.h"
-
 /**
  * This is the number of elements by which the list expands.
- * WARNING: Always use doubles for this number (2^X)
  */
 #define BLOCK_SIZE 1024
 
-void initList(List *l) {
+void initList(List *restrict l) {
 	l->list = malloc(sizeof(mpz_t) * BLOCK_SIZE);
 	if(!l->list) {
 		fprintf(stderr, "Failed to allocate memory to list!\n");
@@ -20,16 +17,18 @@ void initList(List *l) {
 	l->end = 0;
 }
 
-void deInitList(List *l) {
+void deInitList(List *restrict l) {
+	for(size_t i = 0; i < l->size; ++i) {
+		mpz_clear(l->list[i]);
+	}
 	free(l->list);
 }
 
 void addToList(List *l, mpz_t n) {
 	if(l->end == l->size) {
 		l->size += BLOCK_SIZE;
-		if(unlikely(l->size == 0)) {
-			fprintf(stderr,
-					"size has reached limit of `long long int' type!\n");
+		if(l->size == 0) {
+			fprintf(stderr, "`l->size' has overflowed!\n");
 			exit(1);
 		}
 		void *tmp = realloc(l->list, sizeof(mpz_t) * l->size);

src/list.h

@@ -1,3 +1,10 @@
+/**
+ * @file list.h
+ * @author Deathsbreed <deathsbreed@themusicinnoise.net>
+ * @brief Code responsible for List management.
+ * @details Code responsible for the definition and management of the
+ * List object.
+ */
 #pragma once
 #include <gmp.h>
 #include <stdbool.h>
@@ -7,25 +14,24 @@
  */
 typedef struct {
 	mpz_t *list; //!< The list of elements
-	unsigned long long int size; //!< How many elements are in the list
-	unsigned long long int end; //!< The last element of the list (in use)
+	size_t size; //!< How many elements are in the list
+	size_t end; //!< The last element of the list (in use)
 } List;
 
 /**
  * @brief Initialize a List.
  * @details Initialize the list and its variables, allocating memory
- * to the pointer array inside. Returns true on success and false on
- * failure.
+ * to the pointer array inside.
  * @param[in] l A pointer to a List type to be initialized.
  */
-void initList(List *l);
+void initList(List *restrict l);
 
 /**
  * @brief Deinitialize a List.
  * @details Release all memory that has been allocated to the list.
  * @param[in] l A pointer to a List type to be deinitialized.
  */
-void deInitList(List *l);
+void deInitList(List *restrict l);
 
 /**
  * @brief Adds a new item to a List type.

src/main.c

@@ -2,20 +2,58 @@
 #include <stdlib.h>
 #include <signal.h>
 #include <stdbool.h>
+#include <getopt.h>
 #include <gmp.h>
 
 #include "list.h"
 
+#define VERSION "v0.5"
+
 static bool run;
+
+void printUsage(char *progName);
 void leave();
 
-int main(void) {
-	printf("Indivisible v0.2\n");
+int main(int argc, char *argv[]) {
+	bool f_help = false, f_version = false, f_quiet = false;
+
+	int c;
+	while((c = getopt(argc, argv, "hvq")) != -1) {
+		switch(c) {
+			case 'h':
+				f_help = true;
+				break;
+			case 'v':
+				f_version = true;
+				break;
+			case 'q':
+				f_quiet = true;
+				break;
+			default:
+				printUsage(argv[0]);
+				exit(1);
+		}
+	}
+
+	if(f_help) {
+		printUsage(argv[0]);
+		puts(" -h     print this help information");
+		puts(" -v     print version number of program");
+		puts(" -q     quiet mode");
+		return 0;
+	} else if(f_version) {
+		printf("Indivisible %s\n", VERSION);
+		return 0;
+	}
 
 	// Quit on ^C by setting `run = false'
 	run = true;
 	signal(SIGINT, leave);
 
+	if(f_quiet) {
+		puts("Use Ctrl+C (SIGINT) to exit.");
+	}
+
 	// Primes we've found
 	List primes;
 	initList(&primes);
@@ -27,39 +65,61 @@ int main(void) {
 	// Add 2, a known prime to this list
 	mpz_set_ui(num, 2);
 	addToList(&primes, num);
-	if(mpz_out_str(stdout, 10, num) == 0) {
-		fprintf(stderr, "Could not print to `stdout'!\n");
-		exit(1);
-	}
-	printf("\n");
-	mpz_add_ui(num, num, 1);
-
-	do {
-		// Loop through found primes
-		for(unsigned long long int i = 0; i < primes.size; ++i) {
-			// If `num' is divisible by a prime then go to the next number
-			if(mpz_divisible_p(num, primes.list[i]) != 0) goto nextPrime;
-		}
-
-		// `num' is a prime so we add it to the list and print it
-		addToList(&primes, num);
+	if(!f_quiet) {
 		if(mpz_out_str(stdout, 10, num) == 0) {
 			fprintf(stderr, "Could not print to `stdout'!\n");
 			exit(1);
 		}
 		printf("\n");
+	}
+	mpz_add_ui(num, num, 1);
+
+	// Variable for half `num'
+	mpz_t halfNum;
+	mpz_init(halfNum);
+
+	do {
+		// Calculate half of `num'
+		mpz_fdiv_q_ui(halfNum, num, 2);
+		/**
+		 * Loop through primes we've found until we get to half of the number
+		 * we're analyzing
+		 */
+		for(size_t i = 0; mpz_cmp(primes.list[i], halfNum) < 0; ++i) {
+			// If `num' is divisible by a prime then go to the next number
+			if(mpz_divisible_p(num, primes.list[i]) != 0)
+				goto nextPrime;
+		}
+
+		// `num' is a prime so we add it to the list and print it
+		addToList(&primes, num);
+		if(!f_quiet) {
+			if(mpz_out_str(stdout, 10, num) == 0) {
+				fprintf(stderr, "Could not print to `stdout'!\n");
+				exit(1);
+			}
+			printf("\n");
+		}
 
 nextPrime:
 		// Add 2 (skip even numbers since they're all divisible by 2)
 		mpz_add_ui(num, num, 2);
 	} while(run);
 
+	printf("Found %zu primes.\n", primes.end);
+	puts("Clearing memory...");
+	// Clear GMP variables
+	mpz_clear(halfNum);
+	mpz_clear(num);
 	// Deinitialize the list
 	deInitList(&primes);
+
+	puts("Exit successful.");
 	return 0;
 }
 
-void leave() {
-	printf("Exiting...\n");
-	run = false;
+void printUsage(char *progName) {
+	printf("%s [-v | -h | -q]\n", progName);
 }
+
+void leave() { run = false; }

src/optimizers.h

@@ -1,3 +0,0 @@
-#pragma once
-#define likely(x)    __builtin_expect(!!(x), 1)
-#define unlikely(x)  __builtin_expect(!!(x), 0)